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Better knowledge of food search behaviour in fish is essential for studies that aim to improve longline fishing, particularly through bait development. This review provides an overview of our understanding of how fish detect and locate sources of food odour, focusing on the stimuli and sensory modalities involved, and on factors that affect feeding activity. Studies that identify feeding attractants and efforts to develop alternative longline baits are presented. The review reveals that such studies are few in number, and that to date there are no alternatives to traditional baits in commercial longlining despite the growing demand for these resources, which are also used for human consumption. The chemical compounds that elicit food search behaviour differ from species to species, and species selectivity could be improved by incorporating specific feeding attractants in manufactured baits. The unique properties of chemical stimuli and odour dispersal form the basis for improving longline efficiency through the development of a long-lasting bait. Vision is important in prey capture, and manufactured baits can be made more visible than natural baits by increasing the contrast (e.g. via fluorescent or polarising coatings) and creating motion through buoyancy. Physical properties such as size, shape, texture and strength can also be manipulated in a manufactured bait to improve catch efficiency. Knowledge obtained from studies of various aspects of food search behaviour is of paramount importance for future research aimed at alternative bait development and improving longline fishing. | non-battery |
Studies reporting altered susceptibility to visual illusions in autistic individuals compared to that typically developing individuals have been taken to reflect differences in perception (e.g. reduced global processing), but could instead reflect differences in higher-level decision-making strategies. | non-battery |
Selenium nanoparticles are encapsulated uniformly with reduced graphene oxide (Se@RGO) by a simple self-assembly process. The Se@RGO composite has as high as 80 wt% of Se, which is much larger than that of other selenium-based cathode materials. The Se@RGO cathode delivers high capacity and rate capability in a Li–Se battery because of the large capacity of Se, highly dispersed Se nanoparticles in the RGO framework and high conductivity of Se and RGO nanocomposite cathode. A large initial discharge capacity of 533 mAh g−1 at 0.2C was produced based on the total mass of Se@RGO nanocomposites and the capacity could remain at 265 mAh g−1 after 200 cycles at 0.2C and additional 300 cycles at 1C. The electrode also shows an excellent capacity of 250 mAh g−1 at 5C (∼3.4 A g−1). The superior electrochemical performance suggests that the Se@RGO composite is a promising cathode in high-energy and high-power Li–Se battery. | battery |
Hybrid hollow polymeric microspheres (HPMSs) are synthesized by encapsulating the supramolecular vesicles with polyphosphazene through a rapid one-step polycondensation reaction. Subsequent carbonization treatments of the HPMSs lead to corresponding hollow carbon microspheres (HCMSs) with well-preserved geometry. The sizes of HPMSs and HCMSs are controlled by the vesicles, which is directly determined by the feeding ratio of the assembly units. Electrodes based on HCMSs showed a specific capacitance of 314.6F/g at a current density of 0.2A/g in 6M KOH electrolyte, 180.0F/g at a current density of 30A/g, and high stability of 98.2% of capacity retention after 2000 cycles. Both the high surface area and high heteroatoms level of HCMSs contribute to the excellent capacitive performance. Meanwhile, the hollow carbon structure ensured the satisfactory capacitive performance by increasing utilization efficiency of the surface area as well as achieving short diffusion paths for electrolyte ions. | battery |
Résumé Introduction La cranioplastie après craniectomie décompressive chez le traumatisé crânien sévère permet souvent d’améliorer l’état clinique de ces patients, sans que la physiopathologie exacte ne soit totalement expliquée. L’amélioration de l’hémodynamique et du métabolisme cérébral locaux pourraient être une explication. Nous avons évalué l’impact de la cranioplastie sur l’évolution clinique des traumatisés crâniens sévères et sur l’évolution de la perfusion cérébrale. Patients et méthodes Cette étude multicentrique et prospective a concerné 24 patients traumatisés crâniens graves ayant eu une cranioplastie dans les 12 semaines suivant la craniectomie décompressive. Une évaluation neurologique et cognitive, et de la perfusion cérébrale par scanner de perfusion et doppler transcrânien a été réalisée avant et après cranioplastie. Résultats Une amélioration neurologique et cognitive significative a été observée chez 92 % des patients à six mois de la cranioplastie. La perfusion cérébrale était globalement améliorée dès six semaines postopératoires prédominant du côté de la cranioplastie. Les vitesses de circulation sanguine systoliques et diastoliques étaient augmentées dans les deux artères cérébrales moyennes. Conclusion La cranioplastie après craniectomie décompressive semble améliorer le pronostic fonctionnel des traumatisés crâniens sévères via une amélioration globale de la perfusion cérébrale. | non-battery |
Social cognition has received increasing attention in schizophrenia due to its theoretical relevance to core features of the disorder as well as the marked deficits in social functioning exhibited by these patients. However, there remains a need to develop and validate measures of social cognitive abilities and to demonstrate that they are constructs that are separable from non-social neurocognitive processes. In the current study, the Wechsler Adult Intelligence Scale-Revised (WAIS-R) was administered to 169 males with schizophrenia, and test results were subjected to confirmatory factor analysis (CFA) to determine if those WAIS-R subtests containing social content would form a distinct Social Cognition (SC) factor. CFA was used to evaluate various models that hypothesized an SC factor, and for comparison purposes the same models were evaluated in the WAIS-R standardization sample. Results confirmed the presence of a four-factor model that included an SC factor, as well as the more commonly reported Verbal Comprehension, Perceptual Organization, and Working Memory factors. The SC factor consisted of the Picture Arrangement and Picture Completion subtests, and demonstrated small but significant correlations with disorganization and negative symptoms, as well as with an index of social functioning. Results provide support for the validity of the SC factor as a measure of social cognition in schizophrenia, and demonstrate that at least some aspects of social cognition represent separable cognitive domains in schizophrenia. | non-battery |
An explicit model predictive control (EMPC) system for a hybrid battery-ultracapacitor power source is proposed and experimentally verified in this paper. The main advantage of using the EMPC system is that the control law computation is reduced to evaluation of an explicitly defined piecewise linear function of the states. Separate EMPC systems for the total output current loop, the battery loop and the ultracapacitor loop are designed. This modular design approach allows evaluation of the performance of each individual EMPC system separately and also improves the convergence of the EMPC system design algorithm as the models used to design each loop are smaller. In order to protect the hybrid power source, the designed EMPC systems maintain operation of the hybrid power source within specified constraints, namely, battery and ultracapacitor current constraints, battery state of charge constraints and ultracapacitor voltage constraints. At the same time, the total output current EMPC system allocates high frequency current changes to the ultracapacitor and the low frequency current changes to the battery thus extending the battery lifetime. Presented experimental results verify that the hybrid power source operates within the specified constraints while allocating high and low frequency current changes to the ultracapacitor and battery respectively. | battery |
This paper proposes a high performance single-stage inverter topology for the autonomous operation of a solar photovoltaic system. The proposed configuration which can boost the low voltage of photovoltaic (PV) array, can also convert the solar dc power into high quality ac power for driving autonomous loads without any filter. An MPPT circuit with parallel connection is implemented so that the part of the energy generated is processed by the dc–dc converter to supply dc loads. The line current total harmonic distortion (THD) obtained using this configuration is quite reasonable. The proposed topology has several desirable features such as low cost and compact size as number of switches used, are limited to four as against six switches used in classical two-stage inverters. In this paper analysis, simulation and experimental results are presented. | battery |
Diabetes is a disease that has to be managed through appropriate lifestyle. Technology can help with this, particularly when it is designed so that it does not impose an additional burden on the patient. This paper presents an approach that combines machine-learning and symbolic reasoning to recognise high-level lifestyle activities using sensor data obtained primarily from the patient’s smartphone. We compare five methods for machine-learning which differ in the amount of manually labelled data by the user, to investigate the trade-off between the labelling effort and recognition accuracy. In an evaluation on real-life data, the highest accuracy of 83.4 % was achieved by the MCAT method, which is capable of gradually adapting to each user. | non-battery |
The thermal management of a cylindrical battery cell by a phase change material (PCM)/compressed expanded natural graphite (CENG) is investigated in this study. The transient thermal behaviour of both the battery and the PCM/CENG is described with a simplified one-dimensional model taking into account the physical and phase change properties of the PCM/CENG composite. The 1D analytical/computational model yielded nearly identical results to the three-dimensional simulation results for various cooling strategies. Therefore, the 1D model is sufficient to describe the transient behaviour of the battery cooled by a PCM/CENG composite. Moreover, the maximum temperature reached by the PCM/CENG cooling strategy is much lower than that by the forced convection in the same configuration. In the test case studied, the PCM showed superior transient characteristics to forced convection cooling. The PCM cooling is able to maintain a lower maximum temperature during the melting process and to extend the transient time for temperature rise. Furthermore, the graphite-matrix bulk density is identified as an important parameter for optimising the PCM/CENG cooling strategy. | battery |
Cd(OH)2 nanowires have been synthesized on nickel foam by a simple template-free growth method. Structural characterization by SEM and TEM indicated that the Cd(OH)2 formed a porous film on the surface of the nickel foam skeletons. The thickness of the film reached approximately 25μm and the nanowires have diameters of around ∼100nm. The nanowires is confirmed to be pure phase hexagonal Cd(OH)2 by X-ray diffraction. The electrochemical capacitance behaviors of the Cd(OH)2 nanowires electrode are investigated by cyclic voltammetry, galvanostatic charge/discharge and electrochemical impedance spectroscopy tests. The Cd(OH)2 electrode performed in different electrolyte demonstrates that nanowires possess supercapacitance properties in the presence of high concentration OH− ion. The specific capacitances as high as 1164.8Fg−1 at 1Ag−1 and 257.6Fg−1 at 10Ag−1 are obtained in 6moldm−3 KOH solution. The remarkably high capacitance of the Cd(OH)2 nanowire electrode might be attributed to its unique 3D open structure for easy access of electrolyte ions, large surface area and high electrochemical activity. This work demonstrates that Cd(OH)2 nanowires electrode has potential application in electrochemical capacitors. | battery |
Aluminum-ion batteries, emerging as a promising post-lithium battery solution, have been a subject of increasing research interest. Yet, most existing aluminum-ion research has focused on electrode materials development and synthesis. There has been a lack of fundamental understanding of the electrode processes and thus theoretical guidelines for electrode materials selection and design. In this study, by using density functional theory, we for the first time report a first-principles investigation on the thermodynamic and kinetic properties of aluminum intercalation into two common TiO2 polymorphs, i.e., anatase and rutile. After examining the aluminum intercalation sites, intercalation voltages, storage capacities and aluminum diffusion paths in both cases, we demonstrate that the stable aluminum intercalation site locates at the center of the O6 octahedral for TiO2 rutile and off center for TiO2 anatase. The maximum achievable Al/Ti ratios for rutile and anatase are 0.34375 and 0.36111, respectively. Although rutile is found to have an aluminum storage capacity slightly higher than anatase, the theoretical specific energy of rutile can reach 20.90 Wh kg−1, nearly twice as high as anatase (9.84 Wh kg−1). Moreover, the diffusion coefficient of aluminum ions in rutile is 10−9 cm2 s−1, significantly higher than that in anatase (10−20 cm2 s−1). In this regard, TiO2 rutile appears to be a better candidate than anatase as an electrode material for aluminum-ion batteries. | battery |
We investigated how preschoolers use their understanding of the actions available to a speaker to resolve referential ambiguity. In this study, 58 3- and 4-year-olds were presented with arrays of eight objects in a toy house and were instructed to retrieve various objects from the display. The trials varied in terms of whether the speaker’s hands were empty or full when she requested an object as well as whether the request was ambiguous (i.e., more than one potential referent) or unambiguous (i.e., only one potential referent). Results demonstrated that both 3- and 4-year-olds were sensitive to speaker action constraints and used this information to guide on-line processing (as indexed by eye gaze measures) and to make explicit referential decisions. | non-battery |
A three-dimensional transient model is developed for a non-aqueous-electrolyte lithium-air battery to investigate numerically key phenomena during discharging. The proposed model rigorously assesses lithium peroxide (Li2O2) formation and growth in an air electrode, and its complex interactions with electrochemical reactions and species/charge transport. We assume that the porous air electrode mainly consists of sphere-like carbon particles, and hence a spherical film growth model is adopted to simulate the precipitation of Li2O2 on the spherical carbon surfaces. The model is first validated against voltage evolution data measured at different discharging current densities. Good agreement between the simulation results and experimental data is achieved, demonstrating that the model accurately captures voltage decline behaviors due to accumulated Li2O2 in the air electrode. Additional simulations are carried out with different air electrode designs in order to establish the optimization strategy for the air electrode. Detailed simulation results, including multidimensional contours, clearly indicate that the electrode thickness and degree of electrolyte filling are key factors for improving the discharging performance of lithium-air batteries. | battery |
Background Functional cerebral asymmetries (FCAs) are known to fluctuate across the menstrual cycle. The visual line-bisection task administered to normally cycling women showed different patterns of the interhemispheric interactions during menses and the midluteal cycle phase. However, the contribution of estrogens and progestins hormones to this phenomenon is still unclear. Study Design The aim of our study was to show a variation of FCAs in women administered oral contraceptives (OCs) using the visual line-bisection task. Visual line-bisection task with three horizontal lines was administered to 36 healthy women taking a 21-day OC. Twenty-nine patients were right handed. The task was administered during OC intake (day 10) and at the end of the pill-free period. Results The right-handed women showed a significant leftward bias of veridical center on the first and third lines during OC intake compared with an opposite rightward bias during the pill-free period. The same phenomenon of contralateral deviation was observed in left-handed women on day 10 of OC intake. Conclusions The results of this study confirm a hormonal modulation on interhemispheric interaction and suggest that OCs may improve the interhemispheric interaction reducing FCAs compared with the low hormone level period. This opens new insights in OC prescription and choice of administration schedule in order to improve cognitive performances. | non-battery |
A new catalyst electrode was prepared in which Pt particles were homogeneously distributed into a poly(3,4-ethylenedioxythiophene)–poly(styrene sulfonic acid) (PEDOT–PSS) matrix. Catalytic activity and stability for the oxidation of methanol were studied by using cyclic voltammetry and chronoamperometry. For comparative purposes, bulk Pt and PEDOT–PSS based electrodes were fabricated and tested. Enhanced electrocatalytic activity toward the oxidation of methanol was noticed when Pt particles were embedded into the PEDOT–PSS matrix. A high catalytic current for methanol oxidation (2.51mAcm−2) was found for the PEDOT–PSS–Pt electrode in comparison to bulk Pt electrode (0.45mAcm−2) at +0.6V (versus Ag/AgCl). The enhanced electrocatalytic activity might be due to the dispersion of Pt particles into the PEDOT–PSS matrix and the synergistic effects between the dispersed Pt particles and the PEDOT–PSS matrix. The morphology and crystalline behavior of PEDOT–PSS–Pt and simple ITO/Pt films were determined by X-ray diffraction (XRD) analysis and scanning electron microscopy (SEM) and correlated with the enhanced electrocatalytic activity for the Pt-dispersed PEDOT–PSS electrode. | battery |
The effect of δ-Al2O3 nanoparticles (size∼10nm) on the ionic conductivity and related properties of a solid polymer electrolyte (SPE) that consists of low molecular weight (M w=2000) poly(ethylene) glycol (PEG) complexed with LiClO4 is studied in detail using XRD, DSC, TPD, NMR, and complex impedance methods. The maximum ionic conductivity σ=7.3×10−7 Scm−1 observed for pristine (PEG)46LiClO4 is found to be dependent on the content of δ-Al2O3 filter; it shows a peak value of σ=4.5×10−6 Scm−1 for 10mol% filler. This is nearly an order of magnitude enhancement of the ionic conductivity and is found by DSC studies to be related to a decrease in the crystalline regions in the SPE, while the glass transition temperature T g and the melting temperature T m remain essentially unchanged. 7Li NMR motional narrowing points to an increase in the effective mobility of the lithium ions on doping with the nanoparticles. The temperature dependence of σ can be divided into two regions, one consistent with the Arrhenius behavior and the other with the Vogel, Tamman and Fulcher equation. The activation energy is found to be the lowest for the 10mol% doped sample. It is concluded that doping with nanoparticles leads to an enhancement of conductivity due to a decrease in the crystallinity and the activation energy, as well as to an increase in the effective mobility of Li ions. | battery |
The study of errors in learning and the search for patterns to explain their causes have always been of great interest to researchers and educators alike. Mistakes are a constant in students’ solutions to mathematical problems and are inseparable from the learning process. It is essential, then, to diagnose and address the mistakes made by students so as to allow them to reflect on their errors and adjust their knowledge. To this end, we have created a system that tracks all the actions carried out by a student when solving a mathematical algorithm, not just the final results, and which is capable of diagnosing the faults and possible causes. It can also recommend the actions to be taken based on the individual difficulties encountered. In short, we have created a personalized teaching system whose features could be particularly useful for special-needs students, such as those with Down syndrome. This paper explains the error detection modules in the addition, subtraction and error-adapted assistance algorithms. This work is part of a multidisciplinary research effort financed by R&D project called “Divermates”, of the Ministry of Labor and Social Affairs, and involving personnel from the Computer Engineering and Mathematics and Fine Arts Education Departments of the University of La Laguna, as well as professionals from the Tenerife Trisomic 21 Association (ATT21). | non-battery |
Developing an electrode material with improved ionic transport dynamics in a battery has been the focus of research. Here, we report a facile one-step hydrothermal synthesis method to prepare anode material of ultra-small SnS nanocrystals (NCs) anchored on N-doped graphene nanosheets (SnS/N-G), which is expected to significantly the dynamics of lithium transport, enabling an exceptional capacity of 1120.3 mAh g−1 at 0.1 A g−1 after 130 cycles and superior rate capabilities of 446.3 and 340.7 mAh g−1 at 2 and 3 A g−1, respectively. Furthermore, the lithiation/delithiation behaviors of SnS/N-G anode were observed in real time using in situ transmission electron microscopy to reveal the corresponding kinetics. By tracking the full lithiation procedure, in situ electron diffraction and high-resolution TEM imaging found that the original SnS phase was firstly transformed to Sn phase by conversion reaction and then to Li22Sn5 phase by alloying reaction. Notably, a stable and reversible phase transformation was established between Li22Sn5 and Sn phases during subsequent charge-discharge cycles. In the meantime, the volume expansion-induced pulverization of SnS NCs was evidently alleviated by graphene matrix that not only provided a two-dimensional support to buffer the volume change, but also improved the ion migration kinetics, as corroborated by superior rate capability. | battery |
This paper describes a model identification procedure for identifying an electro-thermal model of lithium ion batteries used in automotive applications. The dynamic model structure adopted is based on an equivalent circuit model whose parameters are scheduled on the state-of-charge, temperature, and current direction. Linear spline functions are used as the functional form for the parametric dependence. The model identified in this way is valid inside a large range of temperatures and state-of-charge, so that the resulting model can be used for automotive applications such as on-board estimation of the state-of-charge and state-of-health. The model coefficients are identified using a multiple step genetic algorithm based optimization procedure designed for large scale optimization problems. The validity of the procedure is demonstrated experimentally for an A123 lithium ion iron-phosphate battery. | battery |
In the early 1960s, a PhD student in physics, Costas Papaliolios, designed a simple—and playful—system of Polaroid polarizer filters with a specific goal in mind: explaining the core principles behind Julian Schwinger’s quantum mechanical measurement algebra, developed at Harvard in the late 1940s and based on the Stern-Gerlach experiment confirming the quantization of electron spin. Papaliolios dubbed his invention “quantum toys.” This article looks at the origins and function of this amusing pedagogical device, which landed half a century later in the Collection of Historical Scientific Instruments at Harvard University. Rendering the abstract tangible was one of Papaliolios’s demonstration tactics in reforming basic teaching of quantum mechanics. This article contends that Papaliolios’s motivation in creating the quantum toys came from a renowned endeavor aimed, inter alia, at reforming high-school physics training in the United States: Harvard Project Physics. The pedagogical study of these quantum toys, finally, compels us to revisit the central role playful discovery performs in pedagogy, at all levels of training and in all fields of knowledge.
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Large variations exist in the revenue prediction of grid-scale storage due to uncertainties in operations of storage technologies. Here the authors integrate the economic evaluation of energy storage with key battery parameters for a realistic measure of revenues.
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To obtain a good estimation of particle size distribution and concentration encountered by car passengers during their journeys, an electrical low-pressure impactor was installed in a car. Two measurement campaigns were carried out. The first one covered various traffic conditions in urban and rural areas near Rouen (France). The second campaign covered several journeys up and down the same tunnel. Measurements were recorded in the range 30nm–10μm at 1Hz frequency. The size distributions show two main shapes depending mainly on the concentration. For high concentrations the distributions correspond to diesel emissions with the mode comprised between 60 and 100nm. For low concentrations the maximum of the distribution is located in the finest particle class of the device, between 30 and 60nm. The concentrations observed are generally less than 50000 partcm−3 but may reach more than 106 partcm−3 during specific road events. Likewise high-concentration values may be regularly observed at the end of the tunnel along which the concentration increases linearly, after a surprising decrease. One main conclusion is that on-road measurements are necessary for a correct evaluation of the conditions encountered by car passengers. | non-battery |
Profiles of verbal learning and memory performance were compared for typically developing children and for four developmental disorders characterized by different patterns of language functioning: specific language impairment, early focal brain damage, Williams Syndrome, and Down Syndrome. A list-learning task was used that allowed a detailed examination of the process of verbal learning, recall, and recognition (California Verbal Learning Test—Children’s Version). Distinct patterns of performance characterized the four disorders. These patterns were consistent with the language deficits typically seen in the disorders, with the exception of a dissociation seen in Williams Syndrome. | non-battery |
Spinel Ni-dopped MnCo2O4 powder with fast Li+ intercalation pseudocapacitance is prepared from transition metal carbonates of Ni, Co and Mn as precursors through a solvothermal synthesis followed by an annealing treatment. As-made products are nanovoids submicron-spheres (the diameter is 500 nm–700nm) with an obvious yolk-shell structure and uniform elements distribution. As an anode material with fast Li+ intercalation pseudocapacitance for lithium-ion battery (LIB), the Ni-dopped MnCo2O4 submicron-spheres exhibit an impressively first discharge efficiency (70%) and outstanding large-current cycling performance. The excellent electrochemical performance is closely ascribed to Li+ intercalation pseudocapacitance and the yolk-shell structure, which can effectively prevent the particles from being pulverized, and alleviate the volume changes of particles during the cycling process. In addition, the doping of Ni metal element to MnCo2O4 greatly enhances the electrochemical stability of MnCo2O4, due to the complementarities and synergies between the three metallic elements during the process of Li insertion or extraction reactions. | battery |
Aqueous supercapacitors are attracting increasing attention owing to their high power density, cyclability and environmental friendliness. However, the energy density of common aqueous supercapacitors are restricted by low cell voltage and narrow voltage window. Here we demonstrate that such limitations can be overcome with advanced hybrid supercapacitors using multi-layered water-stable protected lithium negative electrode combined with high concentration “water-in-salt” electrolyte. 4 V-class cell voltage with wide voltage window can be delivered for advanced hybrid supercapacitors with capacitive or pesudocapacitive positive electrodes. A typical advanced hybrid supercapacitor with MnO2 electrode shows a 4.4 V maximum cell voltage with a 1.5 V window, an energy density of 405 Wh kg MnO 2 − 1 at a power density of 0.88 kW kg MnO 2 − 1 . A high energy density of 163 Wh kg MnO 2 − 1 is maintained at a power density of 16.7 kW kg MnO 2 − 1 . These advanced hybrid supercapacitors show acceptable cycle stability and good energy retentions (around 90% within 3000 cycles). | battery |
Recent research has described the structure of psychopathology as including one general and multiple specific factors, and this structure has been found in samples across development. However, little work has examined whether this structure is consistent across time, particularly in young children, within the same sample. Further, few studies have examined factors that influence the magnitude of the stability of latent dimensions of psychopathology. In the present study, we examine these issues in a community sample of 545 children assessed at ages 3 and 6. In addition, we explored child temperament, parental history of psychopathology, and parenting behaviors as potential moderators of the longitudinal stability of latent dimensions of psychopathology. We found that the same bifactor model structure identified at age 3 provided an adequate fit to the data at age 6. Further, our model revealed significant homotypic stability of the general, internalizing, and externalizing specific factors. We also found evidence of differentiation of psychopathology over time with the general factor at age 3 predicting the externalizing factor at age 6. However, we failed to identify moderators of the longitudinal associations between psychopathology latent factors. Overall, our results bolster support for the bifactor structure of psychopathology, particularly in early childhood. | non-battery |
Transition-metal phosphides are considered as candidates for sodium-ion batteries (SIBs) due to the high theoretical specific capacity. However, serious volume variation and agglomeration during sodiation-desodiation hamper their development. Hence, a microporous structure of Ni2P@C–N polyhedrons embedding in highly rough carbon fiber (Ni2P@C–N⊂CF) is designed as self-supporting anode material. The synergistic effect of ultrasmall Ni2P particles (∼5 nm), graphitic carbon shell and adequate free space of carbon fibers buffer the volume change, the uniform distribution of Ni2P particles shorten Na+ diffusion path, the microporous structure endow adequate electrolyte penetration, the graphitic carbon shell and carbon fibers provide high conductive channel, and thus boosting a remarkable sodium storage performance. The Ni2P@C–N⊂CF delivers long cycling stability (196.8 mAh g−1 at 1000 mA g−1 over 1000 cycles with a capacity dropping of 0.04% cycle−1), superior rate capability (197.1 mAh g−1 at 2000 mA g−1, and returned to 752.5 mAh g−1 at 100 mA g−1). Moreover, the flexible half-cell based on the Ni2P@C–N⊂CF electrode still maintains 81.7% capacity retention after repeated bending states. The full cell based on Ni2P@C–N⊂CF and Na3V2(PO4)3 manifests a capacity of 185.9 mAh g−1 over 100 cycles and energy density of ∼217.4 Wh kg−1 for SIBs. Furthermore, the hybrid energy storage mechanism can also contribute to the outstanding electrochemical performance. The Ni2P@C–N⊂CF shows a potential in flexible electrode materials for Na-storage device. | battery |
Application of in situ Mössbauer spectroscopy for studying catalysts and catalytic processes is discussed. Examples are presented to illustrate the potentials of the method by describing studies on supported heterogeneous catalysts performed with 119Sn and 57Fe spectroscopies in cases with certain metals and alloys, oxides and porous substances. The results are interpreted in comparison to the catalytic performance.
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Network neuroscience has relied on a node-centric network model in which cells, populations and regions are linked to one another via anatomical or functional connections. This model cannot account for interactions of edges with one another. In this study, we developed an edge-centric network model that generates constructs ‘edge time series’ and ‘edge functional connectivity’ (eFC). Using network analysis, we show that, at rest, eFC is consistent across datasets and reproducible within the same individual over multiple scan sessions. We demonstrate that clustering eFC yields communities of edges that naturally divide the brain into overlapping clusters, with regions in sensorimotor and attentional networks exhibiting the greatest levels of overlap. We show that eFC is systematically modulated by variation in sensory input. In future work, the edge-centric approach could be useful for identifying novel biomarkers of disease, characterizing individual variation and mapping the architecture of highly resolved neural circuits. | non-battery |
A gridable vehicle (GV) can be used as a small portable power plant (S3P) to enhance the security and reliability of utility grids. Vehicle-to-grid (V2G) technology has drawn great interest in the recent years and its success depends on intelligent scheduling of GVs or S3Ps in constrained parking lots. V2G can reduce dependencies on small expensive units in existing power systems, resulting in reduced operation cost and emissions. It can also increase reserve and reliability of existing power systems. Intelligent unit commitment (UC) with V2G for cost and emission optimization in power system is presented in this paper. As number of gridable vehicles in V2G is much higher than small units of existing systems, UC with V2G is more complex than basic UC for only thermal units. Particle swarm optimization (PSO) is proposed to balance between cost and emission reductions for UC with V2G. PSO can reliably and accurately solve this complex constrained optimization problem easily and quickly. In the proposed solution model, binary PSO optimizes on/off states of power generating units easily. Vehicles are presented by integer numbers instead of zeros and ones to reduce the dimension of the problem. Balanced hybrid PSO optimizes the number of gridable vehicles of V2G in the constrained parking lots. Balanced PSO provides a balance between local and global searching abilities, and finds a balance in reducing both operation cost and emission. Results show a considerable amount of cost and emission reduction with intelligent UC with V2G. Finally, the practicality of UC with V2G is discussed for real-world applications. | battery |
A novel epitaxial thin-film electrode for lithium batteries, with a composition of Li0.92Co0.65Mn1.35O4 and a cubic spinel structure, is fabricated on a SrTiO3(111) single-crystal substrate. Fabrication is carried out by layer-by-layer pulsed laser deposition of LiCoO2 with a layered rock-salt structure and LiMn2O4 with a spinel structure. The electrode is found to exhibit unique disordering of the lithium (8a) and transition-metal (16d) sites, leading to a higher rate capability and cycle retention ratio than those for a thin-film electrode with the same composition prepared by a conventional single-step deposition process. The proposed layer-by-layer deposition method allows an expanded range of compositional and structural variations for lithium battery electrode materials. | battery |
A novel preparation technique was developed for synthesizing carbon-coated LiFePO4 nanoparticles through a combination of spray pyrolysis (SP) with wet ball milling (WBM) followed by heat treatment. Using this technique, the preparation of carbon-coated LiFePO4 nanoparticles was investigated for a wide range of process parameters such as ball-milling time and ball-to-powder ratio. The effect of process parameters on the physical and electrochemical properties of the LiFePO4/C composite was then discussed through the results of X-ray diffraction (XRD) analysis, field-emission scanning electron microscopy (FE-SEM), transmission electron microscopy (TEM), the Brunauer–Emmet–Teller (BET) method and the use of an electrochemical cell of Li|1M LiClO4 in EC:DEC=1:1|LiFePO4. The carbon-coated LiFePO4 nanoparticles were prepared at 500°C by SP and then milled at a rotating speed of 800rpm, a ball-to-powder ratio of 40/0.5 and a ball-milling time of 3h in an Ar atmosphere followed by heat treatment at 600°C for 4h in a N2 +3% H2 atmosphere. SEM observation revealed that the particle size of LiFePO4 was significantly affected by the process parameters. Furthermore, TEM observation revealed that the LiFePO4 nanoparticles with a geometric mean diameter of 146nm were coated with a thin carbon layer of several nanometers by the present method. Electrochemical measurement demonstrated that cells containing carbon-coated LiFePO4 nanoparticles could deliver markedly improved battery performance in terms of discharge capacity, cycling stability and rate capability. The cells exhibited first discharge capacities of 165mAhg−1 at 0.1C, 130mAhg−1 at 5C, 105mAhg−1 at 20C and 75mAhg−1 at 60C with no capacity fading after 100 cycles. | battery |
This work is focused on the responses of some energy metabolism variables in Cnesterodon decemmaculatus adults exposed to cadmium under controlled laboratory conditions. This species has been used as bioindicator for evaluating the effects of different chemicals on diverse biological processes and is frequently used as test organism in ecotoxicity studies that include cadmium as reference toxicant. Animals were exposed for 12 days to the following concentrations: 0, 0.45, and 0.8 mg Cd/L. Food intake, fecal production, specific assimilation, condition factor, mortality percentage, oxygen consumption, oxygen extraction efficiency, specific metabolic rate, ammonia excretion, and ammonia quotient were measured. The overall balance was expressed as scope for growth (SFG). Cadmium-exposed groups showed a significant decrease in food assimilation and condition factor at the end of the exposure. There was an increase in specific metabolic rate and a decrease in SFG in the group exposed to 0.8 mg Cd/L. The condition factor and the SFG appeared as sensitive biomarkers of health status and growth of the animals, respectively. Cadmium-exposed fish reduced food intake, which was reflected in a decreased assimilation with concomitant decline in the external energy supply from feeding. Our results highlight the importance of considering the metabolic status of the test organisms when analyzing the responses of the biomarkers usually used as effect parameters in ecotoxicological evaluations under experimental conditions. | non-battery |
Hollow core–shell nanorods with a nanogap are designed and constructed with the assistance of atomic layer deposition (ALD) for energy storage applications. As a demonstration, CoO nanorods and NiO nanowalls are enclosed by a TiO2 nanotube shell, forming the “wire in tube” and “wall in box” structures, respectively. A thin sacrificial layer of Al2O3 is deposited by ALD and removed eventually, forming a nanogap between the CoO core (or the NiO nanowall) and the TiO2 shell. When they are tested as supercapacitor electrodes, an evident difference between the solid core–shell nanostructure and hollow ones can be found; for example, the hollow structure shows ∼2 to 4 times the capacitance compared to the solid wires. The electrochemical properties are also superior compared to the bare nanorods without the nanotube shell. The enhancement is ascribed to the conformal hollow design which provides enlarged specific surface areas and a shorter ion transport path. It is prospected that such a positive nanogap effect may also exist in other electrochemical cell electrodes such as lithium ion batteries and fuel cells.
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Nowadays, the energy storage technology is bringing new opportunities to the power systems, not only providing the electric grid with regulation, reserve and backup services, but also filling the gap between the timing of production and consumption. This enables price arbitrage techniques, aimed at maximising the economic revenue obtained by charging or discharging the storage, based on the time variation of electricity prices. This paper shows how to optimise the operation of a storage device in presence of a PV generating plant, possibly combined with a local load. An optimisation technique based on a dynamic programming tool implemented with the open source Modelica language is here proposed and tested on different case studies. In particular, different storage sizes and losses models have been considered, as well as the dependence of the storage lifetime on the depth of discharge of its operational cycles. Finally, a payback analysis calibrated on present and future cost scenarios is presented and discussed. | battery |
Mobile cloud computing is a new paradigm that uses cloud computing resources to overcome the limitations of mobile computing. Due to its complexity, dependability and performance studies of mobile clouds may require composite modeling techniques, using distinct models for each subsystem and combining state-based and non-state-based formalisms. This paper uses hierarchical modeling and four different sensitivity analysis techniques to determine the parameters that cause the greatest impact on the availability of a mobile cloud. The results show that distinct approaches provide similar results regarding the sensitivity ranking, with specific exceptions. A combined evaluation indicates that system availability may be improved effectively by focusing on a reduced set of factors that produce large variation on the measure of interest. The time needed to replace a fully discharged battery in the mobile device is a parameter with high impact on steady-state availability, as well as the coverage factor for the failures of some cloud servers. This paper also shows that a sensitivity analysis through partial derivatives may not capture the real level of impact for some parameters in a discrete domain, such as the number of active servers. The analysis through percentage differences, or the factorial design of experiments, fulfills such a gap. | non-battery |
Polymer electrolytes offer the most promising solution to address the all-solid-state battery requirements such as flexibility, leak-proof packing and easy processing. In this study, a polymer blend of 25mol% poly(acrylic acid) (PAA) and 75mol% poly(vinyl alcohol) (PVA) was optimized based on its thermal, mechanical and structural properties. The ionic liquid (IL) electrolyte, 1-butyl-1-methylpyrrolidinium bis(trifluoromethanesulfonyl)imide (PYRTFSI) with 0.2m lithium bis(trifluoromethansulfonyl)imide (LiTFSI), was added to the polymer blend in different molar ratios. A maximum ionic conductivity of 1mScm−1 is observed at 90°C in the membrane with 70mol% IL. Cyclic voltammetry of the polymer electrolytes shows peaks corresponding to lithium stripping (+0.25V vs. Li+/Li) and deposition (−0.3V vs. Li+/Li) processes indicating the occurrence of a highly reversible redox process. The electrochemical stability window of these polymer electrolytes, as determined by linear sweep voltammetry, extends up to 5V, suggesting that these electrolytes could be suitable for batteries that use high voltage cathode materials. A lithium transference number (tLi+) of 0.4 was determined for the polymer electrolytes by using chronoamperometry and impedance measurements. Galvanostatic charge-discharge studies of the polymer electrolytes in a lithium half-cell with LiCoO2 (LCO) as cathode delivers a capacity of about 100mAhg−1 at 60°C. Coin-type half-cell with LiFePO4 (LFP) cathode and the polymer electrolyte containing 70mol% IL delivered a capacity of 172mAhg−1. Interestingly, the LFP/polymer composite cathode (LFP-C) delivers a higher capacity (215mAhg−1 at 60°C) than the pristine LiFePO4 cathode. | battery |
In this paper we tackle the optimal Discharge Scheduling of Energy Storage systems Problem (DSESP) in MicroGrids, considering renewable generation, and applying hyper-heuristic (HH) algorithms. The problem consists of, given the generation and load profiles in the MicroGrid, obtaining the optimal discharge scheduling of the Energy Storage System (ESS) that minimizes the consumption from the utility grid. HHs are a novel methodology in optimization problems that constructs a solution to a given problem by means of the application of basic heuristics, evolved using a global search algorithm. This methodology can be easily adapted to solve the DSESP, in this case by using an evolutionary algorithm as global approach. In this paper we detail the adaptations performed to a HH to tackle the DSESP, mainly in the encoding of solutions, and new evolutionary operators that improve the evolution of good solutions to the problem. The performance of the proposed approach has been evaluated in a real Microgrid, with different scenarios of generation and load profiles, obtaining around 5% reduction of the energy consumption from the utility grid. | battery |
Capacity building strategies are widely used to increase the use of research in policy development. However, a lack of well-validated measures for policy contexts has hampered efforts to identify priorities for capacity building and to evaluate the impact of strategies. We aimed to address this gap by developing SEER (Seeking, Engaging with and Evaluating Research), a self-report measure of individual policymakers’ capacity to engage with and use research. | non-battery |
Introduction The current criteria for detecting a Clinical High-Risk (CHR) state for psychosis do not address cognitive impairment. A first step for identifying cognitive markers of psychosis risk would be to determine which aspects of neurocognitive performance are related with more severe psychotic-like symptoms. This study assessed cognitive impairment associated with prodromal symptoms in adolescents receiving public psychiatric treatment. Methods 189 adolescents were recruited from consecutive new patients aged 15–18 attending mainly outpatient adolescent psychiatric units in Helsinki. They had been screened for prodromal symptoms using the Prodromal Questionnaire, and all screen-positives as well as a random sample of screen-negatives were interviewed using the Structured Interview for Prodromal Symptoms (SIPS) and underwent testing using a large, standardized neurocognitive test battery. The sample included 62 adolescents who met the CHR criteria (CHR) and 112 who did not (non-CHR). A healthy control sample (n =72) was also included to provide age- and gender-matched norms. Results The CHR group performed worse on visuospatial tasks than the non-CHR group. Among CHR adolescents, negative symptoms were associated with slower processing speed and poorer performance on verbal tasks. Among non-CHR adolescents, positive symptoms were associated with poorer performance on visuospatial tasks, and negative symptoms with poorer performance on verbal tasks. Conclusion Clinical high-risk status is associated with impaired visuospatial task performance. However, both positive, psychotic-like symptoms and negative symptoms are associated with lower levels of neurocognitive functioning among adolescents in psychiatric treatment regardless of whether CHR criteria are met. Thus, even mild positive and negative symptoms may have clinical relevance in adolescents in psychiatric care. Adolescents with both psychotic-like symptoms and neurocognitive deficits constitute a group requiring special attention. | non-battery |
In a recent meeting of IEA's Annex 23, several members presented their conclusions on the modeling of phase change materials behavior in the context of building applications. These conclusions were in agreement with those of a vast review, involving the survey of more than 250 journal papers, undertaken earlier by the group of École de technologie supérieure. In brief, it can be stated that, at this point, the confidence in reviewed models is too low to use them to predict the future behavior of a building with confidence. Moreover, it was found that overall thermal behaviors of phase change material are poorly known, which by itself creates an intrinsic unknown in any model. Models themselves are most of time suspicious as they are often not tested in a very stringent or exhaustive way. In addition, it also appears that modeling parameters are somewhat too simplified to realistically describe the complete physics needed to predict the real life performance of PCMs added to a building. As a result, steps are now taken to create standard model benchmarks that will improve the confidence of the users. Hopefully, following these efforts, confidence will increase and usage of PCM in buildings should be eased. | battery |
Aspen (Populus tremuloides) trees growing under elevated [CO2] at a free-air CO2 enrichment (FACE) site produced significantly more biomass than control trees. We investigated the molecular mechanisms underlying the observed increase in biomass by producing transcriptomic profiles of the vascular cambium zone (VCZ) and leaves, and then performed a comparative study to identify significantly changed genes and pathways after 12 years exposure to elevated [CO2]. In leaves, elevated [CO2] enhanced expression of genes related to Calvin cycle activity and linked pathways. In the VCZ, the pathways involved in cell growth, cell division, hormone metabolism, and secondary cell wall formation were altered while auxin conjugation, ABA synthesis, and cytokinin glucosylation and degradation were inhibited. Similarly, the genes involved in hemicellulose and pectin biosynthesis were enhanced, but some genes that catalyze important steps in lignin biosynthesis pathway were inhibited. Evidence from systemic analysis supported the functioning of multiple molecular mechanisms that underpin the enhanced radial growth in response to elevated [CO2].
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Voltammetric measurements showed that sodium diphenylamine sulfonate (SDS) could inhibit hydrogen evolution and form complexes with nickel and magnesium ions for Mg–Ni alloy electrodeposition. The characteristics of differential capacity curves from differential pulse anodic stripping voltammetry showed that SDS had an absorption effect on the cathode electrode. Steady state cathode polarization of Mg–Ni alloy measurements on rotating disk copper electrodes were performed, the relative results from the polarization curves indicated that SDS acted as a levelling agent. The phases and morphology of Mg–Ni alloy were examined by X-ray diffraction and scanning electron microscopy. A series of spectra showed that phenothiazine codeposited with Mg–Ni alloy. The value 0.9 of H/M (M=Mg–Ni alloy) was determined by pressure–composition isotherm measurements. The maximum discharge capacity of the alloy was 388 mAh/g; the decay of discharge capacity was studied by electrochemical impedance spectroscopy measurements. | battery |
Purpose To review our experience with plasmin-assisted vitrectomy surgery for the treatment of pediatric macular holes. Design Retrospective, interventional case series. Methods Thirteen pediatric patients aged one to 15 years with a traumatic macular hole underwent surgical repair. All patients underwent surgery between February 1997 and March 2005 with autologous plasmin enzyme-assisted vitrectomy. After induction of posterior vitreous detachment (PVD), vitrectomy with membrane peeling and gas or silicone oil injection were performed followed by prone positioning for seven days. Main outcome measures included anatomic closure rate, visual outcome, and ocular complications. Results The macular hole was closed successfully in 12 (92%) of 13 cases. Of the 12 patients for whom vision could be measured, 11 patients (92%) had visual acuity improvement of 2 or more lines and six patients (50%) achieved vision of 20/50 or better; all of the patients achieved vision better than 20/200. The visual improvement was statistically significant (P = .005, Wilcoxon signed-rank test). Surgical complications included cataract formation in one patient and retinal detachment in one patient. Conclusions Autologous plasmin enzyme may be a helpful adjunct when performing vitrectomy for traumatic macular holes. | non-battery |
Unknown This index is in letter-by-letter order, whereby hyphens and spaces within index headings are ignored in the alphabetization, and it is arranged in set-out style, with a maximum of four levels of heading. Location references refer to the volume number, in bold, followed by the page number. Page numbers suffixed by f or t refer to figures or tables respectively. | non-battery |
Infrequent Non-Speech Gestural Activities (IGAs) such as coughing, deglutition and yawning help identify fine-grained physiological symptoms and chronic psychological conditions which are not directly observable from traditional daily activities. We propose a new wearable smart earring which is capable of differentiating IGAs in daily environment with single integrated accelerometer sensor signal processing. Our prior framework, GeSmart, shows significant improvement in IGAs recognition based on smart earring which necessitates users to replace the earring batteries frequently due to its energy hungry requirement (high sampling frequency) towards fine-grained IGAs recognition. In this improved work, we propose a new segmentation technique along with GeSmart which takes the advantages of change-point detection algorithm to segment sensor data streams, feature extraction and classification thus any machine learning technique can perform significantly well in low sampling rate. We also implement a baseline traditional graphical model based gesture recognition techniques and compare their performances with our model in terms of accuracy, energy consumption and degradation of sampling rate scenarios. Experimental results based on real data traces demonstrate that our approach improves the performances significantly compared to previously proposed solutions. We also apply our segmentation technique on two benchmark datasets to prove the superiority of our technique in low sampling rate scenario. | non-battery |
The electrochemical performances of (LiMn0.6Fe0.4PO4/C)//LiV3O8 ARLB in different aqueous electrolyte, i.e. 0.5M Li2SO4, 2M Li2SO4, saturated Li2SO4 with pH value of 7, 2M LiNO3, 5M LiNO3, saturated LiNO3, saturated LiNO3 with pH value of 7, are studied. The results infer that (LiMn0.6Fe0.4PO4/C)//LiV3O8 ARLB in 5M LiNO3 or saturated LiNO3 aqueous electrolyte with pH value of 7 has favorable specific capacity and rate performance. According to the energy density calculations, the electrochemical performance of (LiMn0.6Fe0.4PO4/C)//LiV3O8 ARLB in the saturated LiNO3 with pH value of 7 is better than that in 5M LiNO3 solution. | battery |
A consortium composed of Thelma Biotel and Center of Oceanography developed and tested an acoustic 3-axis accelerometer transmitter. The first testing phase took place in experimental tanks and consisted of externally attaching prototype data logging tags in Lusitanian toadfish (Halobatrachus didactylus Bloch & Schneider, 1801) and comparing raw logged data with observed behaviours to obtain characteristic accelerometer data patterns that could be assigned to those typical movements. Four behavioural “signatures” were considered, two different burrowing movements, attack towards a prey and general activity. The second phase was the development of a prototype with integrated software capable of identifying those accelerometer typical patterns, process the information and transmit relevant data acoustically. Burrowing movements and activity were detected and transmitted with 100% accuracy while attacks were detected with a 61% successful rate. The third phase took place in the Mira estuary (SW Portugal) with 2 groups (five and six individuals each) of free living toadfish to test the codified acoustic signal transfer from the AccelTag to the acoustic receiver array. The novelty of the AccelTag is that is has the measuring capabilities of an accelerometer archival tag but without the necessity of recapture the tagged fish, since it has the ability of analysing the logged data, extract very detailed species dependent information and transmit the relevant processed data. | non-battery |
In this study, personal values, health, and financial status were investigated as determinants of affective well-being in a sample of 371 recent retirees across 3 years. Personal values, measured with the Portrait Value Questionnaire (Schwartz et al. in J Cross Cult Psychol 32:519–542, 2001), were hypothesized to show direct links to positive affect (PA) and negative affect (NA) as well as to moderate the association between financial and health status and affective well-being. Using structural equation modeling, higher PA was predicted by female gender, better finances, fewer illnesses, and higher self-transcendence (ST), openness to change (OC), and conservation values. Higher NA was predicted by female gender, lower finances, more illnesses, higher self-enhancement (SE) and lower OC values. SE and OC values also moderated the association between financial status and PA. Longitudinal analyses indicated a relatively stable pattern of associations across 3 years. While the impact of finances on affect was stable over time, the effects of health and values increased across 3 years.
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A novel facile hydrothermal modification method is applied to improve the electrochemical performance of the low-cost cathode material Li1.231Mn0.615Ni0.154O2, which is primarily prepared by a solid-combustion approach. The material before and after modifying are characterized by energy dispersive spectrometer (EDS), powder X-ray diffraction (XRD), scanning electron microscopy (SEM), BET and high-resolution transmission electron microscopy (HRTEM). The samples are served as the cathode of lithium-ion batteries and investigated by galvanostatic experiments within a voltage range 2.0–4.8 V (vs. Li/Li+). The results reveal that the electrochemical performance of the Li1.231Mn0.615Ni0.154O2 cathode electrode is prominently enhanced after modifying. The significantly improved electrochemical performance of the Li1.231Mn0.615Ni0.154O2 cathode is attributed largely to the modification of the surface microstructure and the crystallinity. | battery |
This research project is specifically focused on the evaluation of figurative and operational cognitive structures in relation with implemented special educational treatment at the children with visual impairments. The sample was tested by battery U.D.N.80, (Piaget and Inhelder). The evaluated sample includes 71 children with visual impairments at special educational treatment, Belgrade, Serbia. We conclude that there is inhomogeneous achievement of the tested children included in the sample. We can conclude about the necessity of implementation multimodal oriented approach, which focuses the role of special education, behavior modification and cognitive rehabilitation. | non-battery |
There are only few semiconducting materials that have been shaping the progress of third generation photovoltaic cells as much as perovskites. Although they are deceivingly simple in structure, the archetypal AMX3-type perovskites have built-in potential for complex and surprising discoveries. Since 2009, a small and somewhat exotic class of perovskites, which are quite different from the common rock-solid oxide perovskite, have turned over a new leaf in solar cell research. Highlighted as one of the major scientific breakthroughs of the year 2013, the power conversion efficiency of the title compound hybrid organic–inorganic perovskite has now exceeded 18%, making it competitive with thin-film PV technology. In this minireview, a brief history of perovskite materials for photovoltaic applications is reported, the current state-of-the-art is distilled and the basic working mechanisms have been discussed. By analyzing the attainable photocurrent and photovoltage, realizing perovskite solar cells with 20% efficiency for a single junction, and 30% for a tandem configuration on a c-Si solar cell would be realistic.
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The rapid expansion of research on Brain-Computer Interfaces (BCIs) is not only due to the promising solutions offered for persons with physical impairments. There is also a heightened need for understanding BCIs due to the challenges regarding ethics presented by new technology, especially in its impact on the relationship between man and machine. Here we endeavor to present a scoping review of current studies in the field to gain insight into the complexity of BCI use. By examining studies related to BCIs that employ social research methods, we seek to demonstrate the multitude of approaches and concerns from various angles in considering the social and human impact of BCI technology. | non-battery |
Heterostructures composed of reduced graphene oxide and self-organized titania nanotubes (nt-TiO2) are examined as novel electrode material for lithium-ion batteries. The novelty here resides in the deposition of a graphene-like film on self-organized nanotubes and that, as compared with previous materials, the differences in behavior are significant as the heterostructure combines previously reported advantages of self-organized nt-TiO2 with those emerging from the graphene composites. The preparation of this nt-TiO2/graphene hybrid electrode material is described here. The deposition of a graphene film on self-arranged amorphous nt-TiO2 was confirmed by using SEM, Raman spectroscopy and mapping of composition. Lithium test cells display capacities that can exceed 300 mAh g−1 over 100 cycles and that are therefore superior to those of bare nt-TiO2 and anatase or rutile TiO2–graphene hybrid nanostructures. The excellent rate performance of these electrodes makes charge–discharge possible up to at least 300 C-rate. The impedance spectra show that the graphene-like film improves the interface properties in the hybrid electrode. In addition to the environmentally friendly nature of the active electrode material, the moderate working voltage offers an important safety advantage in that it protects the battery from the electroplating phenomena. | battery |
Transition metal oxide-based hybrid material systems have been demonstrated to exhibit significantly improved electrochemical performance as anode materials for lithium ion batteries (LIBs). In this work, porous ZnFe2O4/α-Fe2O3 micro-octahedrons have been designed and fabricated by a facile solvothermal method followed by thermal treatment. The unique structures including the heterojunctions between ZnFe2O4 and α-Fe2O3 NPs and the open inter-connected pores are beneficial for the electrochemical performance. When evaluated as an anode material for LIBs, the as-prepared porous ZnFe2O4/α-Fe2O3 micro-octahedrons show an excellent lithium storage performance. The discharge capacity could reach 1752mAhg−1 after 75 cycles at a current density of 200mAg−1. More importantly, when the current density was increased to as high as 4Ag−1, the ZnFe2O4/α-Fe2O3 electrode can still retain reversible capacity of 1090mAhg−1. The capability and rate performance of the porous ZnFe2O4/α-Fe2O3 micro-octahedrons both are better than those of bare ZnFe2O4 and α-Fe2O3. The superior lithium storage performance of the porous ZnFe2O4/α-Fe2O3 micro-octahedrons is mainly attributed to their unique composition and microstructure, which not only could provide high conductivity, good Li+ diffusion, and large electrode–electrolyte contact area, but also could reduce volume change during charge/discharge process. | battery |
This paper takes the theory of value change as developed by Inglehart as a point of departure and tests its implications for the determinants of human happiness. It investigates whether the importance of post-material concerns for happiness, relative to that of materialist concerns, is indeed higher in rich post-industrial societies. Personal autonomy and job creativity serve as indicators for post-materialist concerns, the income domain as an indicator for materialist concerns. The main assumption is put against data for 48 countries from wave 5 of the World Values Survey, the most recent survey, which covers the full range from poor agrarian to rich post-industrial societies. Employing a multi-level design, the paper indeed reveals a quite consistent pattern towards post-materialist happiness as we move from poor to rich societies. This pattern seems to be driven by both a devalorization of material concerns and a valorization of post-materialist concerns, although the evidence suggests that the former trend is stronger and more linear than the latter. | non-battery |
Thermally regenerative ammonia-based batteries (TRABs) have been developed to harvest low-grade waste heat as electricity. To improve the power production and anodic coulombic efficiency, the use of ethylenediamine as an alternative ligand to ammonia was explored here. The power density of the ethylenediamine-based battery (TRENB) was 85 ± 3 W m−2-electrode area with 2 M ethylenediamine, and 119 ± 4 W m−2 with 3 M ethylenediamine. This power density was 68% higher than that of TRAB. The energy density was 478 Wh m−3-anolyte, which was ∼50% higher than that produced by TRAB. The anodic coulombic efficiency of the TRENB was 77 ± 2%, which was more than twice that obtained using ammonia in a TRAB (35%). The higher anodic efficiency reduced the difference between the anode dissolution and cathode deposition rates, resulting in a process more suitable for closed loop operation. The thermal-electric efficiency based on ethylenediamine separation using waste heat was estimated to be 0.52%, which was lower than that of TRAB (0.86%), mainly due to the more complex separation process. However, this energy recovery could likely be improved through optimization of the ethylenediamine separation process. | battery |
Tuberous sclerosis complex (TSC) is an autosomal dominant disease that affects multiple organs including the brain. TSC is strongly associated with broad neurodevelopmental disorders, including autism spectrum disorder symptomatology. Preclinical TSC studies have indicated altered neuronal chloride homeostasis affecting the polarity of γ-aminobutyric acid (GABA) ergic transmission as a potential treatment target. Bumetanide, a selective NKCC1 chloride importer antagonist, may attenuate depolarizing GABA action, and in that way reduce disease burden. In this open-label pilot study, we tested the effect of bumetanide on a variety of neurophysiological, cognitive, and behavioral measures in children with TSC. | non-battery |
Surgery is the treatment of choice for drug-resistant temporal lobe epilepsy (TLE). However, such surgery frequently causes deficits in language function, especially if performed on the dominant hemisphere. In recent years, the intracarotid amobarbital test (IAT) has been gradually replaced by functional magnetic resonance imaging (fMRI) in the preoperative identification of language areas to estimate the risk of postoperative language decline. In this paper, we review the neural substrates for language processing, how language impairment can result both from TLE itself and from surgical attempts to treat it. Subsequently, we discuss the strengths and limitations of, and current indications for fMRI and IAT during the preoperative workup, both by discussion of the studies that have evaluated them individually and through meta-analysis of data from 31 studies deemed eligible for analysis. Electrocortical stimulation mapping (ESM) is also discussed, as is the usefulness of the novel technique of resting-state fMRI. Finally, surgical techniques designed to avoid or reduce language decline in patients at risk are explored.
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We describe a three-phase use of the Woods Hole Oceanographic Institution's Autonomous Benthic Explorer (ABE), to locate, map and photograph previously undiscovered fields of high temperature submarine hydrothermal vents. Our approach represents both a complement to and a significant advance beyond the prior state of the art. Previously, hydrothermal exploration relied upon deep-tow instruments equipped with sensors that could locate sites of active “black smoker” venting to within a few kilometers. Follow-on CTD tow-yos could then resolve the sites of seafloor venting to length scales of less than a kilometer but rarely to better than a few hundreds of meters. In our new approach ABE: (i) uses sensors to locate the center of a dispersing non-buoyant hydrothermal plume 100–400m above the seabed; (ii) makes high-resolution maps of the seafloor beneath the plume center whilst simultaneously detecting interception of any rising, buoyant hydrothermal plumes; and (iii) dives to the seafloor to take photographs in and around any new vent site to characterize its geologic setting and reveal the nature of any chemosynthetic ecosystems it may host. By conducting all of the above under long-baseline navigation, precise sites of venting can be determined to within 5m. Our approach can be used both to address important scientific issues in their own right and to ensure much more efficient use of other deep-submergence assets such as human occupied vehicles (HOVs) and remotely operated vehicles (ROVs) during follow-on studies. | non-battery |
In this study, 22 children with early left hemisphere (LHD) or right hemisphere (RHD) focal brain lesions (FL, n=14 LHD, n=8 RHD) were administered an English past tense elicitation test (M=6.5 years). Proportion correct and frequency of overregularization and zero-marking errors were compared to age-matched samples of children with specific language impairment (SLI, n=27) and with typical language development (TD, n=27). Similar rates of correct production and error patterns were observed for the children with TD and FL; whereas, children with SLI produced more zero-marking errors than either their FL or TD peers. Performance was predicted by vocabulary level (PPVT-R) for children in all groups, and errors did not differ as a function of lesion side (LHD vs. RHD). Findings are discussed in terms of the nature of brain–language relations and how those relationships develop over the course of language learning. | non-battery |
The genus Erophaca comprises a single herbaceous perennial species with two subspecies distributed at opposite ends of the Mediterranean region. We used nrDNA ITS to investigate the phylogeny of the genus, and AFLP markers (9 primers, 20 populations) to establish the genetic relationship between subspecies, and among populations at each side of the Gibraltar Strait. According to nrDNA ITS, Erophaca is monophyletic, old (Miocene), and sister to the Astragalean clade. Life form attributes and molecular clock estimates suggest that Erophaca is one of the many Tertiary relicts that form part of the present Mediterranean flora. Within the occidental subspecies, European plants are clearly derived from North-African populations (Morocco) which, despite being rare on a regional scale, present the highest genetic diversity (as estimated by private and rare fragment numbers). In general, genetic diversity decreased with increasing distance from Morocco. AFLP and nrDNA ITS markers evidenced that the Eastern and the Western subspecies are genetically distinct. Possible causes for their disjunct distribution are discussed. | non-battery |
Short peptide segments are increasingly found to have critical roles in biological processes but are often difficult to discover. Bioactive peptides can be quickly found through computational approaches, including a new method that has identified several peptides active against platelet function. | non-battery |
Enzymes from hyperthermophilic archaea are potential candidates for industrial use because of their superior pH, thermal, and long-term stability, and are expected to improve the long-term stability of biofuel cells (BFCs). However, the reported multicopper oxidase (MCO) from hyperthermophilic archaea has lower redox potential than MCOs from other organisms, which leads to a decrease in the cell voltage of BFCs. In this study, we attempted to positively shift the redox potential of the MCO from hyperthermophilic archaeon Pyrobaculum aerophilum (McoP). Mutations (M470L and M470F) were introduced into the axial ligand of the T1 copper atom of McoP, and the enzymatic chemistry and redox potentials were compared with that of the parent (M470). The redox potentials of M470L and M470F shifted positively by about 0.07 V compared with that of M470. In addition, the catalytic activity of the mutants towards 2,2′-azino-bis(3-ethylbenzothiazoline-6-sulphonic acid) (ABTS) increased 1.2–1.3-fold. The thermal stability of the mutants and the electrocatalytic performance for O2 reduction of M470F was slightly reduced compared with that of M470. This research provides useful enzymes for application as biocathode catalysts for high-voltage BFCs.
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Divergent thinking (DT) plays a critical role in many creative efforts. Tests of DT are useful estimates of the potential for creative problem solving. This chapter presents the basics of divergent thinking, covering theoretical support and an overview of the different kinds of DT tests and the various scoring methods. It then reviews the factors that can influence divergent thinking, such as knowledge, expertise, openness to experience, and training. Special emphasis is given to investigations related to DT in organizations. Interestingly, in the organizational studies, certain aspects of divergent thinking stand out more than in other domains. Evaluative and convergent processes, for example, are particularly important. The empirical research on evaluative and convergent processes, as they interact with DT, is reviewed. The distinction between interpersonal and intrapersonal evaluation of ideas is discussed, as are the implications for organizational creativity. Recommendations for further studies on divergent thinking are provided. | non-battery |
The purpose of the study was the investigation of VR-induced aftereffects on various basic cognitive abilities and its relationship with cybersickness. Previous studies suggest an adverse effect of VR exposure on simple reaction times. Aftereffects on other basic cognitive abilities have rarely been studied. Sixty participants performed a test battery, that consisted of five different tests, prior and after the immersion into a VR bike application. Participants were assigned to three different experimental conditions using different kinds of displays, motion control devices. Twenty additional participants acted as a control group. Reaction times of simple (χ2(3) = 140.77; p < .001) and choice reaction tasks (two choice: χ2(3) = 66.87; p < .001; four choice: χ2(3) = 55.48; p < .001) deteriorated after VR exposure but remained stable or improved in the control group not exposed to VR. Changes in performance were only weakly related to degrees of cybersickness (.04 < r < .28). We propose a general aftereffect of VR exposure on reaction times that is only slightly related to subjective degrees of cybersickness. Taken together, however, usage of VR systems, even if inducing moderate levels of cybersickness, leads only to minor decrements of cognitive performance.
| non-battery |
Lithium-rich layered metal oxide Li1.1[Ni1/3Co1/3Mn1/3]0.9O2 was investigated as a potential positive electrode material for high-power batteries for hybrid electric vehicle (HEV) applications. In order to evaluate the power and life characteristics of the graphite/Li1.1[Ni1/3Co1/3Mn1/3]0.9O2 cell chemistry, hybrid pulse power characterization (HPPC) and accelerated calendar life tests were conducted on several pouch cells containing electrolytes with and without additives. The data show that the cells containing 0.5wt% lithium bis(oxalate)borate (LiBOB) or vinyl ethyl carbonate (VEC) additives, or the novel lithium difluoro(oxalato)borate (LiDFOB) additive, have much improved cycle and calendar life performance. | battery |
Critical aspects affecting energy storage revenue include high penetrations of renewable generation such as photovoltaics (PV), and significant changes in patterns of demand as a result of widespread uptake of heat pumps. To assess the impact, an optimisation model using mixed integer linear programming (MILP) is proposed, to simultaneously determine the design and operation of battery energy storage for PV-battery systems featuring heat pumps. The annualised capital expenditure (CAPEX), annual operating expenditure (OPEX), self-consumption ratio (SCR), and internal rate of return (IRR) of PV-battery systems are calculated. Sensitivity analysis is carried out with a range of PV capacities and battery prices to understand the complex impact of heat pumps on PV-battery systems. It is shown that with a 3-tier time-of-use pricing tariff, the widespread use of heat pumps generally increases the SCR through the consumption of midday surplus PV, and decreases the optimal capacity of the battery storage. The sensitivity and scenario analysis provides evidence which negates the hypothesis that increased heat pump penetration leads to increased commercial return for PV-battery systems. | battery |
A new technique to produce Li2S/C composites and Li2S cathodes as well as their application in high-capacity Li–S batteries is demonstrated. The simple but effective method converts an easy-to-handle lithium salt-containing composite or electrode to Li2S using H2S. The main advantage is that the conversion to Li2S can be performed towards the final stage of the electrode preparation process, which significantly reduces the need of controlled atmosphere otherwise required for Li2S handling. LiOH is used to demonstrate the technique, and such fabricated Li2S electrode is successfully used in a Li–S battery (half-cell) where it shows discharge capacities of up to 770 mAh g−1 (Li2S) and retained >410 mAh g−1 (Li2S) after 100 cycles at C/5. | battery |
Uniformity of the crystal structure of battery electrodes inside a commercial prismatic Li-ion battery (LiCoO2|C) with a nominal capacity of 1200 mAh were examined by diffraction of a monochromatic photon beam (60 keV). Selected structural parameters related to lithium concentrations in the positive and negative electrodes were determined averaging over cell thickness on a 1 × 1 mm2 grid, thus resembling an experimental radiography technique with a pixel size of 1 mm2, where the diffraction signal is used instead of attenuation of the photon beam. Non-uniformities in a prismatic Li-ion battery were unambiguously revealed by remarkable differences of the diffraction signals and systematic deviations of structural properties at different scan positions. Observed lithium heterogeneities at nominal state-of-charge (SOC) = 100% state are attributed to SOC deviations caused by the current distribution inside the examined prismatic cell. | battery |
A sulfur cathode with enhanced electrochemical properties is prepared by a hydrogel binder owning three-dimensional polymeric network for Li–S batteries. The promising high-performance binder (Alg-Ca2+) is constructed by an in situ interconnection of alginate chains by additive divalent cation with a facile and self-assembly strategy. With the assistance of 3D network, the sulfur/activated carbon composite cathode exhibits a higher rate capability and cycling performance compared to poly(vinylidene fluoride) binder, and the capacity retention is up to 80.6 % after 200 cycles (0.5C, 1C = 1675 mA g−1). Additionally, the electrochemical impedance spectroscopy also reveals a lower electrode resistance and better kinetic characteristics with Alg-Ca2+ as a binder. The improved electrochemical behaviors are assigned to the ability of maintaining the electrode stability due to the excellent mechanical property and amorphous structure. | battery |
In this work, the electrostatic self-assembly of LiFePO4 particles coated with polyelectrolytes on a three-dimensional carbon substrate is described. This new fabrication method allows precise control of ionic and electronic conduction pathways as well as the interfaces between the different electrode components, thus enabling new strategies for tailored electrode designs. Further, it is shown that the polyelectrolytes used to build up the electrode by electrostatic self-assembly can be converted into a conductive matrix by a simple carbonization step. This leads to a firmly adhering carbon film on the surface of LiFePO4, which further improves electron transport. The three-dimensional composite cathode exhibits a high specific capacity even at high current rates as well as a long cycle life. The excellent electrochemical performance can be attributed to the improved three-dimensional structure of the electrode as well as to the obtained intrinsic carbon coating of LiFePO4 particles. | battery |
The research discussed in this paper focused on a systematic methodology to elucidate the controversy about transitions responsible for the photoluminescence (PL) spectrum from porous silicon (PSi) layers etched on a p-type Si wafer, to understand the nature of light emitting mechanisms from PSi. The PL spectrum of PSi, as a function of temperature, shows the existence of broad peaks, initially associated with stable surface states. However, the PL studies as a function of time, under continuous laser fluency, shows the presence of electronic states due to silicon columns (quantum confinement) and the metastable surface states. Finally, the PL studies, during which the laser was cut off for several hours, confirm that the surface states are metastable. Based on the information provided by these studies, the interpretation of the results indicates that the PL spectrum of PSi is a superposition of porous surface states and states originated in the porous layer considered as a pseudo lattice of the Si bulk. | non-battery |
Nanostructured titanium oxide films are fabricated directly by an anodic electrodeposition strategy at an aqueous TiCl3 solution. Surface morphology shows that the deposited films are consisted of fine particles having 15–25nm in diameter. Annealing temperature influences both the crystal structure and the electrochemical performance of the deposited titanium oxide. When the annealing temperature exceeds 300°C, the poorly crystalline titanium oxide converts into anatase phase. Cyclic voltammograms (CVs) show that the anatase titanium oxide films exhibit reversible insertion/de-insertion of lithium ion in an aqueous LiOH electrolyte. The formation of lithiated titanium oxide is confirmed from an X-ray photoelectron spectroscopy. An optimal annealing temperature is found to be about 400°C in terms of the CV peak current density. In addition, the diffusion coefficient of lithium ion in cathodic process (1.6×10−15 cm2 s−1) is higher than that of anodic process (9.4×10−16 cm2 s−1), probably due to the formation of higher O–Li bond strength during the lithium insertion. | battery |
Sodium lauryl ether sulphate (SLES) is the main chemical component in several lubricant products used for soil conditioning in the mechanized excavation industry using Earth Pressure Balance-Tunnel Boring Machines. During the tunnelling process, huge amounts of excavated soil are produced and the SLES presence can affect the subsequent re-use of this material as a by-product. Currently, there is still no regulatory indication of reliable and sensitive bioassays for monitoring soil quality during the excavation process. The main objective of this work was to verify if the Vibrio fischeri screening test was suitable as a consistent and precautionary tool for this specific purpose. Firstly, the ecotoxicity (EC20 and EC50) of the SLES standard solution and three commercial products (SLES content from 10 to 50%) were evaluated to select the most environmental friendly product. Subsequently, soil samples from about 2 years of tunnelling in a real construction site, conditioned with the selected product, were evaluated for their environmental compatibility with the prescriptions of an Italian site-specific protocol. The latter established 2 mg/L as a threshold value for SLES concentration in soil water extracts and a no toxic response (≤20%) for the Vibrio fischeri test. The comparison of the bacterium bioluminescence inhibition values (%) with analytical determinations showed an ecotoxicity when SLES was >2 mg/L. The toxicity was directly related to SLES concentration, indicating that the V. fischeri test and the SLES analyses are suitable tools for assessing excavated soil as a by-product, ensuring its safe reuse in accordance with a green production process (circular economy). | non-battery |
Optimal PV based EV charging is performed either by predicting or by measuring PV output. However, due to the uncertainties associated with the variables involved, both the charging methods are not only disposed to significant voltage limit violations but also may cause PV energy harvest reduction. Hence, a methodology is proposed in this paper, which utilizes the measured PV output of a given sample and the supplied historical ramp to predict the PV output of the immediate next sample using a non-iterative method. The charging rates of the EV population are, subsequently, adjusted in the interval between the successive samples based on the predicted PV output with the help of a proposed SOC based charging strategy. The proposed methodology has been tested at the University of Queensland (UQ)’s solar and parking facilities coupled with its electric grid. The results show that aside from reducing the probability of voltage limit violations (PVV), the proposed methodology can increase the PV energy harvest. Moreover, it is cost-effective as compared to the conventional method such as onsite battery energy storage deployment. | battery |
Anodes derived from oxides of tin have, of late, been of considerable interest because, in principle, they can store over twice as much lithium as graphite. A nanometric matrix of Li2O generated in situ by the electrochemical reduction of SnO2 can provide a facile environment for the reversible alloying of lithium with tin to a maximum stoichiometry of Li4.4Sn. However, the generation of the matrix leads to a high first-cycle irreversible capacity. With a view to increasing the reversible capacity as well as to reduce the irreversible capacity and capacity fade upon cycling, tin–tin oxide mixtures were investigated. SnO2, synthesized by a chemical precipitation method, was mixed with tin powder at two compositions, viz., 1:2 and 2:1, ball-milled and subjected to cycling studies. A mixture of composition Sn:SnO2 =1:2 exhibited a specific capacity of 549mAhg−1 (13% higher than that for SnO2) with an irreversible capacity, which was 7% lower than that for SnO2 and a capacity fade of 1.4mAhg−1 cycle−1. Electrodes with this composition also exhibited a coulombic efficiency of 99% in the 40 cycles. It appears that a matrix in which tin can be distributed without aggregation is essential for realizing tin oxide anodes with high cyclability. | battery |
Li[Ni1/3Co1/3Mn1/3]O2 powders were synthesized from co-precipitated spherical metal hydroxide, (Ni1/3Co1/3Mn1/3)(OH)2. The preparation of metal hydroxide was significantly dependent on synthetic conditions, such as pH, amount of chelating agent, stirring speed, etc. The optimized condition resulted in (Ni1/3Co1/3Mn1/3)(OH)2, of which the particle size distribution was uniform and the particle shape was spherical, as observed by scanning electron microscopy. Calcination of the uniform metal hydroxide with LiOH at higher temperature led to a well-ordered layer-structured Li[Ni1/3Co1/3Mn1/3]O2, as confirmed by Rietveld refinement of X-ray diffraction pattern. Due to the homogeneity of the metal hydroxide, (Ni1/3Co1/3Mn1/3)(OH)2, the final product, Li[Ni1/3Co1/3Mn1/3]O2, was also significantly uniform, i.e., the average particle size was of about 10μm in diameter and the distribution was relatively narrow. As a result, the corresponding tap-density was also high approximately 2.39gcm−3, of which the value is comparable to that of commercialized LiCoO2. In the voltage range of 2.8–4.3, 2.8–4.4, and 2.8–4.5V, the discharge capacities of Li[Ni1/3Co1/3Mn1/3]O2 electrode were 159, 168, and 177mAhg−1, respectively. For elevated temperature operation (55°C), the resulted capacity was of about 168mAhg−1 with an excellent cyclability. | battery |
This paper reports on the cycling stability of Li plating/stripping on Li6.6La3Zr1.6Ta0.4O12 [LLZ(Ta0.4)] with high sintering density at 25, 60, and 100 °C. Plated/stripped Li thicknesses are sequentially increased to 200 nm, 1.0 μm, and 2.0 μm after every ten cycles. The overpotential gradually increases with cycling Li plating/stripping processes, and the cells eventually short-circuit at 25 and 60 °C. However, the cycling stability of Li plating/stripping significantly improves at 100 °C, and the short-circuiting is prevented perfectly. Moreover, the cycling stability of Li plating/stripping at 25 °C is dramatically improved by pre-cycling the cell at 100 °C. Only heating a cell with Li metal at 100 °C for the same duration does not improve the cycling stability of the cell. It is hence considered that forced migrations of Li atoms and ions across entire Li/LLZ(Ta0.4) interfaces at 100 °C change the properties of the interfacial regions even for the following plating/stripping cycles at 25 °C. | battery |
Language disturbance is one of the main diagnostic features in schizophrenia and abnormalities of brain language areas have been consistently found in schizophrenic patients. The main aim of this study was to describe the impairment of micro and macrolinguistic abilities in a group of twenty-nine schizophrenic patients during the phase of illness stability compared to forty-eight healthy participants matched for age, gender and educational level. Microlinguistic abilities refer to lexical and morpho-syntactic skills, whereas macrolinguistic abilities relate to pragmatic and discourse level processing. Secondary aims were to detect the effect of macrolinguistic on microlinguistic ability, and the neuropsychological impairment associated with the linguistic deficit. The linguistic assessment was performed on story-telling. Three narratives were elicited with the help of a single-picture stimulus and two cartoon stories with six pictures each. A modified version of the Mental Deterioration Battery was used to assess selective cognitive performances. A series of t-tests indicated that all the macrolinguistic variables were significantly impaired in schizophrenic patients in at least one of the three story-tellings. Furthermore, the limited impairment found in microlinguistic abilities was influenced by macrolinguistic performance. Multivariate stepwise regression analyses suggested that reduced attention performances and deficit in executive functions were predictors of linguistic impairment. Language production in schizophrenia is impaired mainly at the macrolinguistic level of processing. It is disordered and filled with irrelevant pieces of information and derailments. Such erratic discourse may be linked to the inability to use pragmatic rules and to cognitive deficits involving factors such as attention, action planning, ordering and sequencing. | non-battery |
Earth-abundant transition metal-based compounds are of high interest as catalysts for sustainable hydrogen fuel generation. The realization of effective electrolysis of water, however, is still limited by the requirement of a high sustainable driving potential above thermodynamic requirements. Here, we report dynamically self-optimized (DSO) NiFe layered double hydroxide (LDH) nanosheets with promising bi-functional performance. Compared with pristine NiFe LDH, DSO NiFe LDH exhibits much lower overpotential for the hydrogen evolution reaction (HER), even outperforming platinum. Under 1 M KOH aqueous electrolyte, the bi-functional DSO catalysts show an overpotential of 184 and −59 mV without iR compensation for oxygen evolution reaction (OER) and HER at 10 mA cm−2. The material system operates at 1.48 V and 1.29 V to reach 10 and 1 mA cm−2 in two-electrode measurements, corresponding to 83% and 95% electricity-to-fuel conversion efficiency with respect to the lower heating value of hydrogen. The material is seen to dynamically reform the active phase of the surface layer during HER and OER, where the pristine and activated catalysts are analyzed with ex situ XPS, SAED and EELS as well as with in situ Raman spectro-electrochemistry. The results show transformation into different active interfacial species during OER and HER, revealing a synergistic interplay between iron and nickel in facilitating water electrolysis.
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The paper is devoted to the development of lithium-ion battery grade negative electrode active materials with higher reversible capacity than that offered by conventional graphite. The authors report on results of their experiments as related to the electrochemical performance of silicon-based materials for lithium-ion batteries. A commercial grade of spherically shaped natural graphite (FormulaBT™ SLA1025) was modified in a number of different ways with nano-sized silicon. The reversible capacity of SLA1025 modified by 9.2wt% of the nano-sized amorphous silicon was seen to be as high as 590mAhg−1. The irreversible capacity loss with this compound was 20%. Lithium-ion batteries using such material were observed to display sharp capacity decay during prolonged cycling. In contrast, the reversible capacity of another experimental grade, the SLA1025 modified by 7.9wt% of the carbon-coated Si was as high as 604mAhg−1. The irreversible capacity loss with this material was as low as 8.1%. This grade, also, was seen to display much better cycling performance than the baseline natural graphite. A series of full lithium-ion rechargeable cells were developed in the CR2016 coin cell configuration. Higher specific capacity of graphite modified by silicon was observed. This allowed decreasing graphite content in the lithium-ion cells by a factor of 1.6. The resultant lithium-ion batteries after optimization of their composition displayed approximately 20% higher gravimetric and volumetric specific energy densities than lithium-ion battery based on conventional natural graphite. | battery |
The precursor for a gel polymer electrolyte (GPE) consisted of tetra (ethylene glycol) diacrylate monomer, benzoyl peroxide, and 1.1M LiPF6/EC:PC:EMC:DEC (30:20:30:20wt.%). LiCoO2/graphite cells were prepared and their electrochemical properties were evaluated at various current densities and temperatures. The viscosity of the precursor containing 5vol.% tetra (ethylene glycol) diacrylate monomer was around 4.6mPas. The ionic conductivity of the gel polymer electrolyte at 20°C was around 6.34×10−3 Scm−1. The gel polymer electrolyte had good electrochemical stability up to 4.5V versus Li/Li+. The capacity of the cell at 2.0C rate was 74% of the discharge capacity at 0.2C rate. The capacity of the cell at temperature of −10°C was 81% of the discharge capacity at temperature of 20°C. Discharge capacity of the cell with gel polymer electrolyte was stable with charge–discharge cycling. | battery |
The effects of Si particle size and the amount of carbon-based conductive additive (CA) on the performance of a Si anode in a Li-ion battery are investigated by adopting combinations of two different Si particle sizes (20 and 3μm on average) and CA contents (15 and 30wt.%), respectively. The CA contains graphitic flakes and nano-sized carbon black. Cyclic voltammetry, charge–discharge tests, scanning electron microscopy and X-ray diffraction establish that the CA content has a profound effect on the cycle-life and irreversible capacity of the Si anode. The former increases, while the latter decreases significantly with increasing CA content. Reducing the particle size of Si, on the other hand, facilitates the alloying/de-alloying kinetics. For instance a cycle-life of over 50 cycles with >96% capacity retention at a charge capacity of 600mAh per g-Si has been demonstrated by adopting of 30wt.% CA and 3μm Si particles. | battery |
Rational electrode architectural design, favorable electrode composition, and versatile synthesis approach play a significant role in developing advanced electrodes for high-performance supercapacitor. In this work, we report a facile approach for fabricating 1D hierarchical CuO@Co x Ni 1−x (OH)2 nanowire arrays grown on 3D highly conductive copper foam. The optimized [email protected](OH)2 electrode delivers an ultrahigh specific capacity of 374.7 mAh g−1 at 2 A g−1 with exceptional rate capability (301.7 mAh g−1 at 50 A g−1) and remarkable cycling stability (95.9% after 10 000 cycles at 50 A g−1). A flexible asymmetric solid-state supercapacitor (ASC) is fabricated using the optimized [email protected](OH)2 as the positive electrode, activated carbon-coated nickel foam as the negative electrode, and polyvinyl alcohol/KOH gel as electrolyte. The flexible ASC operating with a potential window of 0–1.6 V delivers an energy density of 46.5 Wh kg−1 with a power density of 526.9 W kg−1. The ASC also exhibits excellent cycling stability with a capacity retention of 84.3% after 10 000 cycles at a current density of 7 A g−1. | battery |
A new method for the simultaneous measurement of the effective ionic conductivity and effective electronic conductivity in a porous sheet consisting of an electronic conductor and an ionic conductor (electrolyte) is proposed. In this method, two potentiostats and a voltage source are used, and these instruments are connected to the sample via two terminals made of the electronic conductor and two terminals made of the ionic conductor. The underlying principle of this technique does not include any assumption about charge-transfer resistance at the ionic conductor/electronic conductor interface, since the measurement is designed to let the potential difference at the interface be the OCP value at each point throughout the sample. The validity of this method was confirmed by measuring a pseudo-catalyst layer for a proton-exchange membrane fuel cell (PEMFC). The results revealed that the effective ionic and electronic conductivity depends on the relative humidity. | battery |
Electrochemical double layer capacitors (EDLCs) are inherently high power devices when compared to rechargeable batteries. While capacitance and energy storage ability are mainly increased by optimizing the electrode active material or the electrolyte, the power capability could be improved by including conductive additives in the electrode formulations. This publication deals with the use of four different carbon additives – two carbon blacks and two graphites – in standard activated carbon based EDLC electrodes. The investigations include: (i) physical characterization of carbon powder mixtures such as surface area, press density, and electrical resistivity measurements, and (ii), electrochemical characterization via impedance spectroscopy and cyclic voltammetry of full cells made with electrodes containing 5 wt.% of carbon additive and compared to cells made with pure activated carbon electrodes in organic electrolyte. Improved cell performance was observed in both impedance and cyclic voltammetry responses. The results are discussed considering the main characteristics of the different carbon additives, and important considerations about electrode structure and processability are drawn. | battery |
Certain grinding operations need a specially shaped wheel for regular surface texture (RST) generation. In such cases, wheel nominal active surface is reproduced on the ground surface in a special way. The simple version of the method consists in grinding with the wheel having helical grooves which are deeper than the grinding depth. Pattern regularity depends in longer time on wheel wear. The grinding force is thus one of the most important process indicators. A simulation model of grinding process, assuming random arrangement of abrasive grains was developed and is presented in this paper. The model was verified by grinding force measurements. These measurements showed specific features that were different from those characteristic of conventional grinding. Explanations of the untypical effects observed at force–time series signals for the three basic types of surface patterns are provided. | non-battery |
The rechargeable Li-air battery has a key role to play for future renewable energy and electric vehicle industries due to its high energy density. However, it suffers from cycling fading and low rate capability, mainly caused by the problem of cathode. Here we create a nanoporous three-dimensional gas diffusion electrode to replace a conventional composite electrode, prolonging battery cycle life over 200 cycles with higher rate capabilities and high capacities. Electrochemical and spectroscopic characterisations indicate the mechanism for the improvement. | battery |
Electrochromic (EC) devices are capable of reversibly changing optical properties upon charge injection and extraction driven by an externally applied voltage. A nanogenerator (NG) is a device that converts mechanical energy into electricity. This paper demonstrates a self-powered EC device driven by an NG. An average visible optical modulation (ΔTvis) as large as 15.3% was obtained, with electrochromic response time (ERT) and coloration efficiency (CE) of 10 seconds and 58.7 cm2 C−1, respectively. Such a performance is comparable to an EC when powered by a hardwired DC power. This study indicates that the self-powered electrochromic system can be a candidate for monochrome displays or electronic billboards.
| battery |
Nano-size (≤100nm) TiP2O7 is prepared by the urea assisted combustion synthesis, at 450 and 900°C. The compound is characterized by powder X-ray diffraction, Rietveld refinement, high resolution transmission electron microscopy and surface area methods. Lithium cycling properties by way of galvanostatic cycling and cyclic voltammetry (CV) showed a reversible and stable capacity of 60 (±3)mAhg−1 (0.5mole of Li) up to 100 cycles, when cycled at 15mAg−1 between 2–3.4V vs. Li. Non-aqueous hybrid supercapacitor, TiP2O7 (as anode) and activated carbon (AC) (as cathode) has been studied by galvanostatic cycling and CV in the range, 0–3 V at 31mAg−1 and exhibited a specific discharge capacitance of 29 (±1)Fg−1stable in the range, 100–500 cycles. The Ragone plot shows a deliverable maximum of 13Whkg−1 and 371Wkg−1 energy and power density, respectively. | battery |
ABSTRACT This paper describes a method for the preparation of composite cathodes for lithium ion-batteries by using poly vinyl acetate (PVAc) as a binder. PVAc is a non-fluorinated water dispersible polymer commonly used in a large number of industrial applications. The main advantages for using of this polymer are related to its low cost and negligible toxicity. Furthermore, since the PVAc is water processable, its use allows to replace the organic solvent, employed to dissolve the fluorinated polymer normally used as a binder in lithium battery technology, with water. In such a way it is possible to decrease the hazardousness of the preparation process as well as the production costs of the electrodes. In the paper the preparation, characterization and electrochemical performance of a LiFePO4 electrode based on PVAc as the binder is described. Furthermore, to assess the effect of the PVAc binder on the electrode properties, its performance is compared to that of a conventional electrode employing PVdF-HFP as a binder. | battery |
In this article, we will focus on the development of electrical energy storage systems, their working principle, and their fascinating history. Since the early days of electricity, people have tried various methods to store electricity. One of the earliest devices was the Leyden jar which is a simple electrostatic capacitor that could store less than a micro Joule of energy. The battery has been the most popular in storing electricity as it has higher energy density. In this article, we will describe and compare the working of various kinds of batteries and capacitors. We will review the recent technological breakthrough in electrical energy storage devices.
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Lithium-ion batteries are expected to serve as a key technology for large-scale energy storage systems (ESSs), which will help satisfy recent increasing demands for renewable energy utilization. Besides their promising electrochemical performance, the low self-discharge rate (<5% of the stored capacity over 1 month) of lithium-ion batteries is one of their most significant advantages for ESSs. Herein, contrary to conventional belief, we report that the self-discharge of LIBs can be abnormally accelerated when the battery has been exposed even to a routine short-term thermal exposure. We demonstrate that this thermal ‘history’ in addition to the temperature itself is memorized in the battery and accelerates the self-discharge rate. The series of characterizations performed in our work reveal that the electrolyte salt acts as a strong oxidizing agent by vigorously damaging the surface of the cathode, producing an internal ‘parasitic’ lithium source that continuously supplies lithium for the self-discharge. Although it is widely known that battery operation at elevated temperature generally induces faster degradation of capacity over multiple cycles, the key finding here is that not only the operation temperature but also the ‘thermal history’ of the battery should be carefully considered because this history remains and continues to affect the self-discharge rate afterwards. The self-discharge of LIBs has remained largely neglected; however, our findings suggest that close attention must be paid to the self-discharge of LIBs applied to large-scale ESSs, which, unlike mobile electronic devices, will be exposed to various outdoor temperature conditions.
| battery |
A portable system for power generation based on hydrogen and a single proton exchange membrane fuel cell (PEMFC) has been built and operated. The fuel cell is fed in the anode with hydrogen stored in a metal hydrides cartridge, and in the cathode with oxygen from quiescent ambient air (‘air breathing’). The control electronics of the system performs DC–DC conversion from the low voltage (0.5–0.8V) and high current output (200–300mAcm−2) of the single fuel cell, up to 3.3V to power an electronic application. System components assist fuel cell operation, including an electronic valve for anode purging, a fan in front of the open cathode, two supercapacitors for auxiliary power requirements, four LED lights, and a display screen. The influence of the system components on fuel cell behaviour is analyzed. The cathode fan and anodic purging help excess water removal from the electrodes leading to steadier cell response at the expense of extra power consumption. The power system is able to provide above 1W DC electricity to an external application during 20h using 1g of H2. An application consisting of a propeller able to display a luminous message is chosen to test system. It is shown that one single air breathing PEM fuel cell powered with hydrogen may provide high energy density and autonomy for portable applications. | battery |
Information and communication technology (ICT), characterized by continual innovation and rapid technological change, is having a tremendous impact on society. Research and development in ICT are being conducted throughout the technology sector, and fundamental research is being carried out in many university departments of electronics, computer science, and engineering. This paper deals with frontiers of research and trends in selected areas of ICT, including computer hardware, microelectronics, and semiconductor devices and materials—areas that are leading the innovations in ICT. It briefly describes emerging technological developments, and concludes with advances in software engineering. | non-battery |
Nowadays, renewable energy plays a vital role in the sustainable development of a society. In China, renewable energy power has developed rapidly since the implementation of Renewable Energy Act. Through a series of specific incentive measures, especially subsidy policies, China׳s renewable energy power has made great achievements both in technology and application. Based on the state-of-the-art of renewable energy power, this paper comprehensively analyzed the costs and benefits of renewable energy power subsidy in China. The analysis results show the cost of renewable energy power subsidy was 0.248CNY/kWh between 2006 and April 2011, which was distributed among different renewable energy power types (including wind power, biomass power, and solar PV power) or categories (including electricity price, accessing-grid projects, and public independent renewable energy power system). On the other hand, the renewable energy power subsidy also brings benefits to different aspects of the society. Specifically, the environmental benefit amounted to 17.88 billion CNY, and the benefits of guaranteeing energy security, advancing technology innovation and promoting economic development were also noteworthy. | battery |
In this paper, we present an integrated device in which an UV detector and a supercapacitor are built on the same vertical-aligned silicon nanowire (SiNW) array electrode. It is found that the embedded supercapacitor is of an impressive capacitance density of 13.6Fcm−3 and able to power the detector for more than 10h with a single charge in less than 100s. The fast and stable UV light responsivity of the detector has been demonstrated during the whole working period. This low cost high performance device has proved a type of promising applications in which a sensor is seamlessly integrated with a power source for its functions. | battery |
Li-ion battery performance degrades with aging and usage, and the degradation highly depends on how the cell is operated. As such, models used for system design and optimization should ideally capture the impact of those effects, and battery management system should take degradation into consideration and control cell operation carefully. Physics-based electrochemical models have shown the capability of predicting cell performance and degradation, but are computationally time consuming, often precluding its use in control-oriented design/optimization. Based on the constitutive laws which are widely adopted in the electrochemical models, a control-oriented reduced-order degradation model for a commercial LiNiMnCoO2/graphite cell is derived to improve computational efficiency without sacrificing model fidelity. Three primary degradation mechanisms that occur in a typical Li-ion cell are captured: 1) Solid Electrolyte Interface (SEI) layer growth, 2) SEI layer fracture and re-healing, and 3) Active Material loss. The extensive validation against a wide range of experimental data illustrates the ability of the model to accurately predict the capacity loss. | battery |
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