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Materials Science News
First direct observation of solar cell degradation
10 December 2013
With the help of DESY's X-ray light source PETRA III, researchers of Technische Universität München have, for the first time, watched organic solar cells degrade in real time. This work could open new approaches to increasing the stability of this highly promising type of solar cell.
Organic solar cells, especially those based on polymers are inexpensive to produce on a large scale. Thanks to their physical flexibility, they can open up new applications of photovoltaics not possible today. Moreover, they can convert light into electricity at an efficiency of more than ten per cent and could contribute significantly to a large-scale power supply based on renewable sources. However, the efficiency of organic cells still rapidly declines and they have a shorter service life than conventional silicon cells.
At the P03 measuring station of DESY's light source PETRA III, scientists have made the first live observations of the degradation of organic solar cells in operation. To do this, they lit a sample polymer solar cell using a solar simulator, which emits light that matches the spectrum and intensity of sunlight and recorded the electrical characteristics of the cell over time. At intervals ranging from several minutes to as much as one hour, the researchers also looked inside the solar cell using the sharply focused X-ray beam from PETRA III. In this way they were able to watch how the interior structure of the active layer of the solar cell changed in the course of seven hours, while the efficiency of the cell decreased by around 25 per cent.
Electricity is generated in the active layer at what is known as active domains in these solar cells. Here, light is absorbed and charge carriers are released. The diameter of these active domains increased by 17 per cent during the study, from about 70 to more than 80 nanometres (millionths of a millimeter). At the same time, the mean distance between them increased by 19 per cent from 310 nanometres to around 370 nanometres, as the X-ray measurements showed.
"This suggests that during operation small sites disappear permanently in favour of larger ones," explains first author Christoph Schaffer, who is a PhD student in Müller-Buschbaum's group. "Although the domains grow, they also recede from each other, this means that their total active area shrinks. This can precisely explain the observed decline in efficiency."
"The examination explained the mechanism of degradation for the first time. It's a first step," says co-author Dr. Stephan Roth, the DESY scientist with responsibility for measuring station P03. "The next step involves attempting to reduce or control this growth in a targeted manner, for example, through the addition of appropriate substances. Polymer solar cells could conceivably be produced with an internal structure in which the active sites grow to their optimal size during the first hours of operation," adds Müller-Buschbaum. "The consequence of such measures could be that industrially produced cells finally cross the economically crucial efficiency threshold also for long-term operation," emphasises Roth.
This story is reprinted from material from DESY, with editorial changes made by Materials Today. The views expressed in this article do not necessarily represent those of Elsevier. Link to original source.
Plasmonic root of terahertz signals in some carbon nanotubes
10 December 2013
Carbon nanotubes carry plasmonic signals in the terahertz range of the electromagnetic spectrum, but only if they're metallic by nature or doped.
In new research, the Rice University laboratory of physicist Junichiro Kono disproved previous theories that dominant terahertz response comes from narrow-gap semiconducting nanotubes.
Knowing that metallic or doped nanotubes respond with plasmonic waves at terahertz frequencies opens up the possibility that the tubes can be used in a wide array of optoelectronic amplifiers, detectors, polarizers and antennas.
Scientists have long been aware of a terahertz peak in nanotubes, the tiny cylinders of rolled-up carbon that show so much promise for advanced materials. But experiments on batches of nanotubes, which generally grow in a willy-nilly array of types, failed to reveal why it was there.
The origin of the peak was not explainable because researchers were only able to experiment on mixed batches of nanotube types, said Qi Zhang, a graduate student in Kono's group and lead author of the paper. "All the previous work was done with a mixture of semiconducting and metallic tubes. We are the first to clearly identify the plasmonic nature of this terahertz response," he said.
Rice's growing expertise in separating nanotubes by type allowed Kono and his group to test for terahertz peaks in batches of pure metallic nanotubes known as "armchairs" as well as nonmetallic, semiconducting tubes.
"Metallic carbon nanotubes are expected to show plasmon resonance in the terahertz and infrared range, but no group has clearly demonstrated the existence of plasmons in carbon nanotubes," Zhang said. "Previously, people proposed one possible explanation — that the terahertz peak is due to interband absorption in the small band gaps in semiconducting nanotubes. We rejected that in this paper."
Plasmons are free electrons on the surface of metals like gold, silver or even aluminum nanoparticles that, when triggered by a laser or other outside energy, ripple like waves in a pond. Strong waves can trigger plasmon responses in adjacent nanoparticles. They are being investigated at Rice and elsewhere for use in sophisticated electronic and medical applications.
The Kono group's research showed plasmons rippling at terahertz frequencies only along the length of a nanotube, but not across its width. "The only way charge carriers can move around is in the long direction," Kono said. The researchers previously used this fact to demonstrate that aligned carbon nanotubes act as an excellent terahertz polarizer with performance better than commercial polarizers based on metallic grids.
Nanotubes can be thousands of times longer than they are wide, and the ability to grow them (or cut them) to specific lengths or to dope semiconducting nanotubes to add free carriers would make the tubes highly tunable for terahertz frequencies, Kono said.
"This paper only clarifies the origin of this effect," he said. "Now that we understand it, there's so much to do. We will be making various terahertz devices, architectures and systems based on carbon nanotube plasmons."
This story is reprinted from material from Rice University, with editorial changes made by Materials Today. The views expressed in this article do not necessarily represent those of Elsevier. Link to original source.
Pioneering path to electrical conductivity in MOFs
9 December 2013
Materials researchers have considered MOF materials primarily for use in gas storage, drug delivery and other conventional applications for porous materials. Their crystalline structure, which resembles molecular scaffolding, consists of rigid organic molecules linked together by metal ions. This hybrid of inorganic and organic components produces an unusual combination of properties: nanoporosity, ultrahigh surface areas and remarkable thermal stability, which are attractive to chemists seeking novel materials that combine the superior performance of traditional inorganic semiconductors with the low cost and ease of fabrication typical of conducting organic polymers.
"When you imagine the 'Tinkertoys' we played with as children, you recall they are essentially wooden balls with holes that you can link together with sticks," Allendorf explained. "MOFs work the same way, only you substitute metal ions for the balls and organic molecules for the sticks."
The resulting open space within the scaffolding can be filled with guest molecules, which gave Sandia's Talin the idea to use the pore to make the MOFs electrically conducting.
"Importantly, MOFs possess a characteristic of molecules that allows us to adapt their properties to a specific application: we can perform chemistry on them, unlike traditional inorganic electronic materials, such as silicon and copper," said Talin. Molecules, he said, represent the "ultimate, small-scale unit" at which electronic devices can be made. They are so difficult to manipulate and organize, however, that practical "molecular electronics" have not been realized. "How you connect to molecules, where you place them — those issues have consistently perplexed materials scientists," said Talin.
So he considered a different approach. "With MOFs, we can get around this problem by using the nanopores to organize molecules. The trick is to pick the right kind of molecule, so that it binds to and interacts with the entire framework." Some MOFs, says Talin, have empty holes in the Tinkertoy balls that can bind molecules that infiltrate the pores.
"This isn't like silicon, which can't change its electrical properties," Talin said. "You can add tiny amounts of dopants to silicon or introduce other impurities, but with our approach, you suddenly have the potential to tailor the material to achieve exactly the properties you want. This is the beauty of molecular electronics."
To test their hypothesis, Sandia and NIST's researchers added a molecule known as tetracyanoquinodimethane, or TCNQ, to their framework. First, they took a substrate with platinum electrodes patterned on its surface and coated it with a thin film of the MOF. The substrate was then dipped in a solution containing the TCNQ molecule, which they knew would seep into the MOF's tiny pores. The MOF film containing the TCNQ bridged the electrode connection points, which then could be connected to a current meter for measuring.
Frankly, I thought it would never work, said Allendorf. But thats the great thing about science: being wrong can be a good thing.Mark Allendorf, Sandia senior scientist
The research team found that the MOF materials were conducting, though at relatively small quantities at first. "It was clear that something good was happening, so we were very excited," said Allendorf.
The experiment was repeated several times with slight but important improvements in film quality achieved by optimizing the laboratory fabrication process.
"Conditions matter, and we had to be very deliberate in how we prepared the framework to accept the guest molecule," said Allendorf. Removing the water and excess solvent from the film is no trivial matter, he said. The research team fine-tuned the process over the course of several months and, in doing so, began to see large leaps in electrical conductivity.
"The increase was massive," said Talin. The conductivity in the material, he says, is now a million times higher than that of the starting material, and a thousand times higher than anything previously reported using a metal-organic framework.
The researchers plan on patenting their approach and also hope to land additional funding in order to experiment with other guest molecules.
This story is reprinted from material from Sandia National Laboratories, with editorial changes made by Materials Today. The views expressed in this article do not necessarily represent those of Elsevier. Link to original source.
Conductive metal-organic frameworks
6 December 2013
Scientists from the National Institute of Standards and Technology (NIST) and Sandia National Laboratories have added something new to a family of engineered, high-tech materials called metal-organic frameworks (MOFs): the ability to conduct electricity. This breakthrough—conductive MOFs—has the potential to make these already remarkable materials even more useful, particularly for detecting gases and toxic substances.
MOFs are three-dimensional crystalline materials with nanoscale pores made up of metal ions linked by various organic molecules. MOFs have huge surface areas, and scientists can easily control the size of their pores and how the pores interact with molecules by tinkering with their chemistries. These characteristics make them ideal for use as catalysts, membranes or sponges for gas storage or for drug delivery, among other applications.
Thousands of new MOF structures are discovered and characterized each year. While they come in a dizzying array of chemistries and structures, none of them conducts electricity well. The NIST/Sandia team developed a method to modify the electrical conductivity of MOF thin films and to control it over six orders of magnitude. Their findings will appear in the journal Science.*
"MOFs are typically extremely poor electrical conductors because their constituent building blocks, the organic linkers and the metal ions, don't really talk to each other in terms of electrical conduction," says NIST materials engineer Andrea Centrone. "Our work points to a way of controlling and increasing their conductivity."
The group accomplished this by "infiltrating an insulating MOF with redox-active, conjugated guest molecules."
In other words, they infused and bound electron-sharing molecules into MOF thin films to create a material that is stable in air and approximately a million times more conductive than the unaltered MOF.
"Based on several spectroscopic experiments, we believe that the guest molecules serve two important purposes: they create additional bridges between the metal ions—copper, in this case—and they accept electrical charge," says NIST chemist Veronika Szalai.
According to NIST physicist Paul Haney, who provided some modeling for the experimental data, the arrangement of the guest molecules in the MOF creates a unique conductivity mechanism while preserving the benefits of the porous MOF crystalline structure.
These porous and conductive MOFs may be the first in an entirely new class of materials that could be used for sensing, conformal electronics (electronics that can bend and conform to unusual shapes), and other as-yet-unknown applications.
"Our discovery gives chemists and engineers a whole new degree of freedom to tailor these materials for their technological applications," says Centrone. "I would not be surprised if solar cells could be made using this new class of materials."
This story is reprinted from material from NIST, with editorial changes made by Materials Today. The views expressed in this article do not necessarily represent those of Elsevier. Link to original source.
Dissolving stone, molecule by molecule
6 December 2013
Scientists from Rice University and the University of Bremen's Center for Marine Environmental Sciences (MARUM) in Germany have combined cutting-edge experimental techniques and computer simulations to find a new way of predicting how water dissolves crystalline structures like those found in natural stone and cement.
"We need to gain a better understanding of dissolution mechanisms to better predict the fate of certain materials, both in nature and in man-made systems," said lead investigator Andreas Lüttge, a professor of mineralogy at MARUM and professor emeritus and research professor in Earth science at Rice. His team specializes in studying the thin boundary layer that forms between minerals and fluids.
Boundary layers are ubiquitous in nature; they occur when raindrops fall on stone, water seeps through soil and the ocean meets the sea floor. Scientists and engineers have long been interested in accurately explaining how crystalline materials, including many minerals and stones, interact with and are dissolved by water. Calculations about the rate of these dissolution processes are critical in many fields of science and engineering.
At the boundary layer where quartz and water meet, multiple chemical reactions occur. Some of these happen simultaneously and others take place in succession. In the new study, the researchers sought to create a computerized model that could accurately simulate the complex chemistry at the boundary layer.
"The new model simulates the dissolution kinetics at the boundary layer with greater precision than earlier stochastic models operating at the same scale," Kurganskaya said. "Existing simulations rely on rate constants assigned to a wide range of possible reactions, and as a result, the total material flux from the surface have an inherent variance range — a plus or minus factor that is always there."
One reason the team's simulations more accurately represent real processes is that its models incorporate actual measurements from cutting-edge instruments and from high-tech materials, including glass ceramics and nanomaterials. With a special imaging technique called "vertical scanning interferometry," which the group at MARUM and Rice helped to develop, the team scanned the crystal surfaces of both minerals and manufactured materials to generate topographic maps with a resolution of a just a few nanometers, or billionths of a meter.
"We found that dissolution rates that were predicted using rate constants were sometimes off by as much as two orders of magnitude," Lüttge said.
The new method for more precisely predicting dissolution processes could revolutionize the way engineers and scientists make many calculations related to a myriad of things, including the stability of building materials, the longevity of materials used for radioactive waste storage and more, he said.
"Further work is needed to prove the broad utility of the method," he said. "In the next phase of research, we plan to test our simulations on larger systems and over longer periods."
This story is reprinted from material from Rice University, with editorial changes made by Materials Today. The views expressed in this article do not necessarily represent those of Elsevier. Link to original source.
Nonlinear light-generating zero-index metamaterial
6 December 2013
A research team used a unique optical metamaterial with a refractive index of zero to generate "phase mismatch–free nonlinear light," meaning the generated light waves move through the material gaining strength in all directions. This phase mismatch-free quality holds promise for quantum computing and networking, and future light sources based on nonlinear optics – the phenomena that occur when interactions with light modify a material's properties.
"In our demonstration of nonlinear dynamics in an optical metamaterial with zero-index refraction, equal amounts of nonlinearly generated waves are observed in both forward and backward propagation directions," says Zhang. "The removal of phase matching in nonlinear optical metamaterials may lead to applications such as efficient multidirectional light emissions for novel light sources and the generation of entangled photons for quantum networking."
Metamaterials are artificial nanofabricated constructs whose optical properties arise from the physical structure of their superlattices rather than their chemical composition. They've garnered a lot of attention in recent years because their unique structure affords electromagnetic properties unattainable in nature. For example, a metamaterial can have a negative index of refraction, the ability to bend light back towards the source, unlike materials found in nature, which always bend light forward away from the source.
"The concept of phase-mismatch free nonlinear interactions provides a new degree of freedom in controlling the nonlinear dynamics in a metamaterial."Kevin OBrien, co-lead author.
In their work with metamaterials, Zhang and his research group have generated the world's first optical invisibility cloak, mimicked black holes, and created the first plasmonic nanolasers.
Nonlinear optical processes are always a challenge to achieve and maintain because of the phase-mismatch problem. The interaction of intense laser light with a nonlinear material can generate new light of a different color, but can also lead to the re-absorption of previously generated photons, depending on the relative phase between the two. Different phase velocities lead to destructive interference due to the lack of optical momentum conservation between the photons, known as "phase mismatch" in the jargon of nonlinear optics.
Previously, it was demonstrated that a metamaterial could be engineered to yield a net refractive index of zero. A beam of light shined through the superlattice of this zero-index metamaterial was unaffected, as if it had passed through a vacuum. The Berkeley researchers surpassed this effort by engineering a zero-index metamaterial that actually generates light through a nonlinear process. This metamaterial features a fishnet structure – a stack of metal-dielectric multilayers with perforated holes. The fishnet consists of 20 alternating layers of gold films 30 nanometers thick and magnesium fluoride films 50 nanometers thick on a 50 nanometer thick silicon nitride membrane.
The researchers tested their metamaterial using a technique called four-wave mixing, in which three beams of light mix in a non-linear medium to create a fourth. Equal amounts of nonlinearly generated waves were observed in both forward and backward propagation directions.
O'Brien and Suchowski have compared the emission of light waves throughout their zero-index metamaterial to that of positive- and negative-index materials by drawing an analogy with the generation of water waves from rocks dropped in a pond.
This story is reprinted from material from Berkeley Lab, with editorial changes made by Materials Today. The views expressed in this article do not necessarily represent those of Elsevier. Link to original source.
"Soft" (and miniaturized) robots
6 December 2013
Increasingly small robots that carry out their functions even inside the human body. No, this isn't a sci-fi dream but a close possibility. On one condition: the miniaturization of these devices requires them to acquire the same "softness" and flexibility as biological tissues. This is the opinion of scientists like Antonio De Simone, from SISSA (the International School for Advanced Studies of Trieste) and Marino Arroyo from the Polytechnic University of Catalonia, who have just published a paper in the Journal of the Mechanics and Physics of Solids: taking inspiration from unicellular water micro-organisms, they studied the locomotion mechanisms of "soft robots".
Forget cogwheels, pistons and levers: miniaturized robots of the future will be "soft". "If I think of the robots of tomorrow, what comes to mind are the tentacles of an octopus or the trunk of an elephant rather than the mechanical arm of a crane or the inner workings of a watch. And if I think of micro-robots then I think of unicellular organisms moving in water. The robots of the future will be increasingly like biological organisms" explains Antonio De Simone who, together with Marino Arroyo of the Polytechnic University of Catalonia, has just published a study in the Journal of the Mechanics and Physics of Solids.
De Simone and his team at SISSA have been studying the movement of euglenids, unicellular aquatic animals, for several years. One of the aims of De Simone's research – which has recently been awarded a European Research Council Advanced Grant of 1,300,000 euro – is to transfer the knowledge acquired in euglenids to micro-robotics, a field that represents a promising challenge for the future. Micro-robots may in fact carry out a number of important functions, for example for human health, by delivering drugs directly to where they are needed, re-opening occluded blood vessels, or helping to close wounds, to name just a few.
To do this, these tiny robots will have to be able to move around efficiently. "Imagine trying to miniaturize a device made up of levers and cogwheels: you can't go below a certain minimal size. Instead, by mimicking biological systems we can go all the way down to cell size, and this is exactly the direction research is taking. We, in particular, are working on movement and studying how certain unicellular organisms with highly efficient locomotion move".
In their study, De Simone and Arroyo simulated euglenid species with different shapes and locomotion methods, based chiefly on cell body deformation and swelling, to describe in detail the mechanics and characteristics of the movement obtained.
"Our work not only helps to understand the movement mechanism of these unicellular organisms, but it provides a knowledge base to plan the locomotion system of future micro-robots".
This story is reprinted from material from SISSA, with editorial changes made by Materials Today. The views expressed in this article do not necessarily represent those of Elsevier. Link to original source.
Nanoscale Shape-Memory Oxide
5 December 2013
Listen up nickel-titanium and all you other shape-memory alloys, there's a new kid on the block that just claimed the championship for elasticity and is primed to take over the shape memory apps market at the nanoscale. A research team at Berkeley Lab has discovered a way to introduce a recoverable strain into bismuth ferrite of up to 14-percent on the nanoscale, larger than any shape-memory effect observed in a metal. This discovery opens the door to applications in a wide range of fields, including medical, energy and electronics.
"Our bismuth ferrite not only displayed the champion shape-memory value, it was also far more stable when reduced to nanometer size than shape-memory alloys," says Jinxing Zhang. "Also because our bismuth ferrite can be activated with only an electrical field rather the thermal fields needed to activate shape-memory alloys, the response time is much faster."
The shape-memory effect is the metallic equivalent of elasticity, in which a solid material "remembers" and recovers its original shape after being deformed by an applied stress. In the past, this has always involved heating. Shape-memory alloys have had a big impact in the medical field with the most prominent being nickel-titanium or "nitinol," which is used in stents for angioplasty, and in mechanical joints. The shape-memory effect is also expected to have a major impact in non-medical applications, such as actuators in smart materials and in Microelectro-Mechanical Systems (MEMS). However, as the size of current shape-memory alloys shrink towards the nano-scale, numerous problems and instabilities arise, including fatigue, micro-cracking and oxidation.
"By achieving the shape-memory effect in an oxide material rather than a metal alloy, we eliminate the surface issues and enable integration with microelectronics," says Zhang. "Our bismuth ferrite also displays an ultra-high work function density during actuation that is almost two orders of magnitude higher than what a metal alloy can generate."
Bismuth ferrite is multiferroic compound comprised of bismuth, iron and oxygen that has been studied extensively in recent years by Ramesh and his research group. As a multiferroic, bismuth ferrite displays both ferroelectric and ferromagnetic properties, meaning it will respond to the application of external electric or magnetic fields. In this latest study, in addition to the conventional thermal activation, an elastic-like phase transition was introduced into bismuth ferrite using only an electric field.
"The application of the electric field allowed us to achieve a phase transformation that was reversible without the assistance of external recovery stress," Ramesh says. "Although aspects such as hysteresis, micro-cracking and so on have to be taken into consideration for real devices, the large shape-memory effect we demonstrated in bismuth ferrite shows it to be an extraordinary material with potential use in future nanoelectromechanical devices and other state-of-art nanosystems."
This story is reprinted from material from Berkeley Lab, with editorial changes made by Materials Today. The views expressed in this article do not necessarily represent those of Elsevier. Link to original source.
From cellulose to textile fiber
3 December 2013
Aalto University has developed a new process with global significance for working cellulose into a textile fiber.
The world's first textile product made from Ioncell cellulose fiber as well as other results yielded by research programs will be introduced at a seminar to be held by the Finnish Bioeconomy Cluster FIBIC Oy on November 20, 2013.
New solutions for utilising fiber-based material in the textile process attract global interest. "The production volumes of cotton cannot keep growing due to the volumes of water and cultivation area it demands. On the other hand, viscose is problematic because of the highly toxic chemicals used in its production," says researcher Michael Hummel at Aalto University.
The process and textile fiber created in the research program open up new kinds of markets for the Finnish forest and garment industries. Finnish cellulose mills provide the new Ioncell fiber with high-quality raw material. "We are still studying the properties of cellulose with the aim of initiating pilot projects that exploit the new process, in cooperation with business enterprises. There's a growing market for an environmentally friendly textile fiber out there," says Hummel.
The new manufacturing process for turning cellulose into quality textile fibers is more ecological than the process employed in traditional viscose production. In addition, the textile fiber produced with the new processing method based on ionic solvents, developed at the University of Helsinki, is clearly stronger than viscose.
"The research has improved the production process and allowed us to create an environmentally friendly product with first-class properties. The Ioncell fiber is ecological and an excellent alternative to cotton and viscose," says Hummel. The research was conducted as part of FIBIC's FuBio Cellulose research program.
The new textile fiber developed by Aalto University can be refined into a high-quality end product. In cooperation with the University's Department of Design, the cellulose fiber was worked into a textile sample.
"I designed and produced a piece of clothing which showcases the material. The new material has an excellent capacity for reproducing shades and it's surprisingly easy to work with," says Marjaana Tanttu, who is studying for her Master's degree in Textile Art and Design.
This story is reprinted from material from Aalto University, with editorial changes made by Materials Today. The views expressed in this article do not necessarily represent those of Elsevier. Link to original source.
Controversy over the use of Roman ingots
2 December 2013
Two thousand years ago, a Roman vessel with ingots of lead extracted from the Sierra of Cartagena sank across the waters from the coast of Sardinia. Since 2011, more than a hundred of these ingots have been used to build the 'Cryogenic Underground Observatory for Rare Events' (CUORE), an advanced detector of neutrinos – almost weightless subatomic particles – at the Gran Sasso National Laboratory in Italy.
In the 18th century, another ship loaded with lead ingots was wrecked on the French coast. A company of treasure hunters retrieved this material and, despite problems with French authorities, managed to sell it to the Cryogenic Dark Matter Search (CDMS) team. This detector located in a mine in Minnesota (USA) looks for signs of the enigmatic dark matter, which is believed to constitute a quarter of the universe.
These two examples have served as reference for the discussion that two researchers have opened between archaeologists, worried by the destruction of underwater cultural heritage, and particle physicists, pleased to have found a unique material for research on neutrinos and dark matter.
As Elena Perez-Alvaro explains to SINC from the University of Birmingham: "Roman lead is essential for conducting these experiments because it offers purity and such low levels of radioactivity – all the more so the longer it has spent underwater – which current methods for producing this metal cannot reach."
"Lead extracted today is naturally contaminated with the isotope Pb-210, which prevents it from being used as shielding for particle detectors", adds physicist Fernando González Zalba from the University of Cambridge.
The two researchers have published a study in the journal 'Rosetta', also commented upon this month in 'Science', which poses a dilemma: Should we sacrifice part of our cultural heritage in order to achieve greater knowledge of the universe and the origin of humankind? Should we yield part of our past to discover more about our future?
"Underwater archaeologists see destruction of heritage as a loss of our past, our history, whilst physicists support basic research to look for answers we do not yet have," remarks Perez-Alvaro, "although this has led to situations in which, for example, private companies like Odyssey trade lead recovered from sunken ships." This is the company that had to return the treasure of the frigate Nuestra Señora de las Mercedes to Spain.
The underwater archaeologist and the physicist are encouraging dialogue between both collectives, as well as developing legislation that regulates these kinds of activities, without limiting them exclusively to archaeologists, and including scientists. "Recovery for knowledge in both fields, and not merely for commercial reasons," the scientists stress.
The jury is still out. In the case of the CUORE detector, for example, in principle the lead from the least well-preserved Roman ingots is used, although their inscriptions are cut and preserved. Some archaeologists also suggests that there are other pieces of valuable metal, such as anchor stocks, rings or tackles for fishing that we should assess whether or not to "sacrifice for science". The problem is that they are protected by UNESCO's 2001 Convention on the protection of underwater cultural heritage if they have been under water more than 10 years and the 2003 Convention for safeguarding intangible cultural heritage.
Regarding the habitual use that Romans made of these ingots, Pérez Álvaro points out that there are many theories, "but they were generally used as water-resistant material for pipes, water tanks or roofs, but also in the manufacture of arms and ammunition."
This story is reprinted from material from The Information and Scientific News Service, with editorial changes made by Materials Today. The views expressed in this article do not necessarily represent those of Elsevier. Link to original source.
Top 10 Materials News from November 2013
2 December 2013
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Iron-based catalysts for greener, cheaper and safer drug and perfume production
29 November 2013
University of Toronto researchers have developed a series of techniques to create a variety of very active iron-based catalysts necessary to produce certain compounds used in the drug and perfume industry. The new synthetic methods promise to be safer, more economical and more environmentally friendly than traditional industrial processes.
The research takes advantage of Earth's extensive supply of iron — the fifth most abundant naturally occurring metal — substituting it in place of the rare elements of ruthenium, rhodium, palladium and platinum traditionally used in the design of the catalysts. The result is an exceptionally efficient class of iron complexes whose abilities rival and even surpass those of conventional industrial catalysts.
"There is a research effort world-wide to make chemical processes more sustainable and green, by replacing the rare, expensive and potentially toxic elements used in hydrogenation, catalytic converters in cars, fuel cells for the efficient conversion of chemical energy into electricity, and silicone coatings, with abundant ions such as iron," says U of T chemistry professor Robert Morris. "Iron is about 10,000 times cheaper to obtain than ruthenium. Less than 200 metric tons of platinum-type metals are mined in the world every year and not all of it can be recycled after use. They are not essential to life and can be toxic."
"We found a way to make the ferrous form of iron behave in a catalytic process much more efficiently than a precious metal. We did this by finding molecules containing nitrogen, phosphorus, carbon and hydrogen, that bond to, and enhance, the reactivity of iron," says Morris.
The scientists inexpensively produced varieties of alcohol with different biological properties — which can be used in flavour and drug synthesis — and different smells, a property important to the perfume industry. In one example from the study, the precursor alcohol to a cancer treatment can be made using the hydrogenation process catalyzed by iron. Using iron, the resulting complex is often a better catalyst than the industrial one based on ruthenium.
The sustainable technology incubator GreenCentre Canada is already pursuing the commercialization of the new iron catalysts.
This story is reprinted from material from University of Toronto, with editorial changes made by Materials Today. The views expressed in this article do not necessarily represent those of Elsevier. Link to original source.
New open access journal launched: Case Studies in Construction Materials
29 November 2013
Elsevier, a world-leading provider of scientific, technical and medical information products and solutions announces the launch of a new open access journal, Case Studies in Construction Materials.
Case Studies in Construction Materials provides an exciting new forum for the rapid publication of structured case studies and short communications on construction materials. The journal functions as an essential compendium for practicing engineers, designers, researchers and other practitioners who are interested in all aspects of construction materials.
Michael Grantham, Editor-in-Chief of the journal, consultant to Sandberg LLP and visiting Professor at Queen's University of Belfast, said of the launch, "Construction work today presents a constant challenge for designers, architects, engineers and contractors. A more detailed understanding of the science behind materials is making wider and more economical use possible. While a number of specialist publications are available for the publication of research data, the publication of case studies for construction materials has been less well served. Case Studies in Construction Materials gives authors an opportunity to publish useful and interesting studies highlighting successes and issues that can result in the use of construction materials, both existing and new.
Dr. Rishi Gupta, Department of Mechanical Engineering, University of Victoria, Canada, author of the first paper published in the journal, said, "This journal provides an excellent forum for practitioners and academics engaged in applied research related to construction materials to present their work as a case study. Open access and swift peer reviewed publication processes ensure that applied research and industry projects reach a wider audience."
Case Studies in Construction Materials is part of a series of "Case Studies in..." open access journals published by Elsevier within the field of engineering. Journals in the series will all follow the article based publishing model, allowing for immediate publication of the final version of a paper without waiting for other articles to be ready to compile a full issue.
For more information or to submit an article, go to Case Studies in Construction Materials.
Slowly cooled DNA transforms nanoparticles into crystal
28 November 2013
Nature builds flawless diamonds, sapphires and other gems. Now a Northwestern University research team is the first to build near-perfect single crystals out of nanoparticles and DNA, using the same structure favored by nature.
A research group developed the "recipe" for using nanomaterials as atoms, DNA as bonds and a little heat to form tiny crystals. This single-crystal recipe builds on superlattice techniques a lab has been developing for nearly two decades.
Mirkin, an experimentalist, teamed up with Monica Olvera de la Cruz, a theoretician, to evaluate the new technique and develop an understanding of it. Given a set of nanoparticles and a specific type of DNA, Olvera de la Cruz showed they can accurately predict the 3-D structure, or crystal shape, into which the disordered components will self-assemble.
The general set of instructions gives researchers unprecedented control over the type and shape of crystals they can build. The Northwestern team worked with gold nanoparticles, but the recipe can be applied to a variety of materials, with potential applications in the fields of materials science, photonics, electronics and catalysis.
A single crystal has order: its crystal lattice is continuous and unbroken throughout. The absence of defects in the material can give these crystals unique mechanical, optical and electrical properties, making them very desirable.
In the Northwestern study, strands of complementary DNA act as bonds between disordered gold nanoparticles, transforming them into an orderly crystal. The researchers determined that the ratio of the DNA linker's length to the size of the nanoparticle is critical.
If you get the right ratio it makes a perfect crystal - isnt that fun?
The ratio affects the energy of the faces of the crystals, which determines the final crystal shape. Ratios that don't follow the recipe lead to large fluctuations in energy and result in a sphere, not a faceted crystal, she explained. With the correct ratio, the energies fluctuate less and result in a crystal every time.
To achieve a self-assembling single crystal in the lab, the research team reports taking two sets of gold nanoparticles outfitted with complementary DNA linker strands. Working with approximately 1 million nanoparticles in water, they heated the solution to a temperature just above the DNA linkers' melting point and then slowly cooled the solution to room temperature, which took two or three days.
The very slow cooling process encouraged the single-stranded DNA to find its complement, resulting in a high-quality single crystal approximately three microns wide.
The researchers determined that the length of DNA connected to each gold nanoparticle can't be much longer than the size of the nanoparticle. In the study, the gold nanoparticles varied from five to 20 nanometers in diameter; for each, the DNA length that led to crystal formation was about 18 base pairs and six single-base "sticky ends."
This story is reprinted from material from Northwestern University, with editorial changes made by Materials Today. The views expressed in this article do not necessarily represent those of Elsevier. Link to original source.
Switching "electromagnons" on and off
28 November 2013
Major industries such as modern microelectronics are based on the interaction between matter and electromagnetism. Electromagnetic signals can be processed and stored in specially tailored materials. In materials science, electric and magnetic effects have usually been studied separately. There are, however, extraordinary materials called "multiferroics", in which electric and magnetic excitations are closely linked. Scientists at the Vienna University of Technology (TU Wien) have now shown in an experiment that magnetic properties and excitations can be influenced by an electric voltage. This opens up completely new possibilities for electronics at high frequencies.
It has been well known for a long time that electricity and magnetism are two sides of the same coin. Waves in free space, such as visible light or mobile phone radiation, always consist of both an electric and a magnetic component. When it comes to material properties, however, electricity and magnetism have been viewed as separate topics. There are materials with magnetic ordering, which react to magnetic fields, and there are materials with electric ordering, which can be influenced by electric fields.
A magnet has a magnetic field, but no electric field. In a piezoelectric crystal, on the other hand, electric fields can be generated, but no magnetic fields. Having both at the same time seemed impossible. "Usually, both effects are created in very different ways", says Professor Andrei Pimenov (TU Vienna). "Magnetic ordering comes from electrons aligning their magnetic moments, electric ordering comes from positive and negative charges moving with respect to one another."
In 2006, Andrei Pimenov (while working at Augsburg University) found evidence of excitations which are based on both electric and magnetic ordering. These excitations, which have been dubbed "electromagnons", have been hotly debated by materials scientists ever since. Now Pimenov and his team have succeeded in switching such excitations on and off with an electric field in a special material made of dysprosium, manganese and oxygen (DyMnO3).
In this material, many electrons align their magnetic moments at low temperatures. Each electron has a magnetic direction which is slightly distorted with respect to the adjoining electron – therefore the electrons create spiral of magnetic moments. The spiral has two possible orientations – clockwise or counterclockwise – and, surprisingly, an external electric field can switch between these two possibilities.
In magneto-electric materials, the charges and the magnetic moments of the atoms are connected. In dysprosium manganese oxide, this connection is particularly strong: "When the magnetic moments wobble, the electric charges move too", says Andrei Pimenov. In this material, magnetic moments and electric charges simultaneously play a part in the excitation, and therefore both can be influenced by one single external field.
The effect can be demonstrated by sending terahertz radiation through the material: The polarization of the terahertz beam is changed if the multiferroic material exhibits magnetic ordering. If the magnetic spiral in the material can be switched with an electric field, this electric field eventually determines, whether the polarization of the terahertz beam is being rotated.
There are many ideas for future applications: Wherever it is desirable to combine the respective advantages of magnetic and electric effects, the new magneto-electric materials could be used in the future. This could lead to new kinds of amplifiers, transistors or data storage devices. Also, highly sensitive sensors could be built with electromagnon technology.
This story is reprinted from material from Vienna University of Technology, with editorial changes made by Materials Today. The views expressed in this article do not necessarily represent those of Elsevier. Link to original source.
Holistic cell design for longer battery life
27 November 2013
Researchers at the U.S. Department of Energy's Lawrence Berkeley National Laboratory (Berkeley Lab) have demonstrated in the laboratory a lithium-sulfur (Li/S) battery that has more than twice the specific energy of lithium-ion batteries, and that lasts for more than 1,500 cycles of charge-discharge with minimal decay of the battery's capacity. This is the longest cycle life reported so far for any lithium-sulfur battery.
Demand for high-performance batteries for electric and hybrid electric vehicles capable of matching the range and power of the combustion engine encourages scientists to develop new battery chemistries that could deliver more power and energy than lithium-ion batteries, currently the best performing battery chemistry in the marketplace.
For electric vehicles to have a 300-mile range, the battery should provide a cell-level specific energy of 350 to 400 Watt-hours/kilogram (Wh/kg). This would require almost double the specific energy (about 200 Wh/kg) of current lithium-ion batteries. The batteries would also need to have at least 1,000, and preferably 1,500 charge-discharge cycles without showing a noticeable power or energy storage capacity loss.
Our cells may provide a substantial opportunity for the development of zero-emission vehicles with a driving range similar to that of gasoline vehiclesElton Cairns, of the Environmental Energy Technologies Division (EETD) at Berkeley Lab
The battery initially showed an estimated cell-specific energy of more than 500 Wh/kg and it maintained it at >300 Wh/kg after 1,000 cycles—much higher than that of currently available lithium-ion cells.
The team is now seeking support for the continuing development of the Li/S cell, including higher sulfur utilization, operation under extreme conditions, and scale-up. Partnerships with industry are being sought. The next steps in the development are to further increase the cell energy density, improve cell performance under extreme conditions, and scale up to larger cells.
This story is reprinted from material from the Berkeley Lab, with editorial changes made by Materials Today. The views expressed in this article do not necessarily represent those of Elsevier. Link to original source.
Opening a door to smart devices
27 November 2013
Researchers from North Carolina State University have for the first time integrated a material called bismuth ferrite (BFO) as a single crystal onto a silicon chip, opening the door to a new generation of multifunctional, smart devices.
BFO has both ferromagnetic and ferroelectric properties, meaning that it can be magnetized by running an electric current through the material. Potential applications for BFO include new magnetic memory devices, smart sensors and spintronics technologies.
Integrating the BFO into the silicon substrate as a single crystal makes the BFO more efficient by limiting the amount of electric charge that "leaks" out of the BFO into the substrate.
We can now look at developing smart devices that can sense, manipulate and respond to data more quickly because it all happens on one chipDr. Jay Narayan, John C. Fan Distinguished Chair Professor of Materials Science and Engineering at NC State
The researchers also found that they can switch the polarity of the BFO's magnetic field with as little as four volts, which is comparable to the voltage needed in existing integrated circuits. This is a key to developing functional technologies because higher voltages and fields are impractical and use more energy, which could damage and disrupt electronic functions.
Similarly, the researchers found that a low-strength, external magnetic field – measured at 300 Oersted, a unit of magnetic field strength – can also switch the BFO's polarity. This is significant because external magnetic fields don't generate heat in the BFO, which could be important for some applications.
This story is reprinted from material from NC State University, with editorial changes made by Materials Today. The views expressed in this article do not necessarily represent those of Elsevier. Link to original source.
New technique controls dimensions of gold nanorods
26 November 2013
North Carolina State University researchers have a developed a technique for efficiently producing nanoscale gold rods in large quantities while simultaneously controlling the dimensions of the nanorods and their optical properties. The optical properties of gold nanorods make them desirable for use in biomedical applications ranging from imaging technologies to cancer treatment.
"This technique should facilitate the economical manufacture of large volumes of gold nanorods," says Dr. Joseph Tracy, an associate professor of materials science and engineering at NC State and senior author of a paper on the work. "And that should be good news for both the science community and the biomedical research and development community."
The NC State team started with an existing technique, in which gold nanorods are formed by mixing two chemical solutions together. However, that technique only converts 30 percent of the gold into nanorods – the rest remains dissolved in solution.
To convert the remaining 70 percent of the gold into nanorods, the researchers added a continuous stream of ascorbic acid (better known as vitamin C) to the solution, while constantly stirring the mixture. The ascorbic acid essentially pulls the gold out of the solution and deposits it on the existing nanorods.
But the researchers also found that the slower they added the ascorbic acid, the stubbier the nanorods became. This is important because the optical properties of gold nanorods depend on their "aspect ratio" – their relative height and width. For example, long, thin gold nanorods absorb light at wavelengths greater than 800 nanometers (in the near infrared spectrum), while shorter, wider gold nanorods absorb light at wavelengths below 700 nanometers (red or dark red).
"The ability to fine-tune these optical properties will likely be useful for the development of new biomedical applications," Tracy says.
This story is reprinted from material from North Carolina State University, with editorial changes made by Materials Today. The views expressed in this article do not necessarily represent those of Elsevier. Link to original source.
Advancing wireless power transfer for vehicles
25 November 2013
Researchers from North Carolina State University have developed new technology and techniques for transmitting power wirelessly from a stationary source to a mobile receiver – moving engineers closer to their goal of creating highway "stations" that can recharge electric vehicles wirelessly as the vehicles drive by.
"We've made changes to both the receiver and the transmitter in order to make wireless energy transfer safer and more efficient," says Dr. Srdjan Lukic, an assistant professor of electrical engineering at NC State and senior author of a paper on the research.
The researchers developed a series of segmented transmitter coils, each of which broadcasts a low-level electromagnetic field. The researchers also created a receiver coil that is the same size as each of the transmitter coils, and which can be placed in a car or other mobile platform. The size of the coils is important, because coils of the same size transfer energy more efficiently.
The researchers modified the receiver so that when it comes into range and couples with a transmitter coil, that specific transmitter coil automatically increases its current – boosting its magnetic field strength and the related transfer of energy by 400 percent. The transmitter coil's current returns to normal levels when the receiver passes out of the range of the transmitter.
These modifications improve on previous mobile, wireless power transfer techniques.
One previous approach was to use large transmitter coils. But this approach created a powerful and imprecise field that could couple to the frame of a car or other metal objects passing through the field. Because of the magnetic field's strength, which is required to transfer sufficient power to the receiver, these electromagnetic field "leaks" raised safety concerns and reduced system efficiency.
Another previous approach used smaller transmitter coils, which addressed safety and efficiency concerns. But this approach would require a very large number of transmitters to effectively "cover" a section of the roadway, adding substantial cost and complexity to the system, and requiring very precise vehicle position detection technology.
"We tried to take the best from both of those approaches," Lukic says.
Lukic and his team have developed a small, functional prototype of their system, and are now working to both scale it up and increase the power of the system.
Currently, at peak efficiency, the new system can transmit energy at a rate of 0.5 kilowatts (kW). "Our goal is to move from 0.5 kW into the 50 kW range," Lukic says. "That would make it more practical."
This story is reprinted from material from NC State University, with editorial changes made by Materials Today. The views expressed in this article do not necessarily represent those of Elsevier. Link to original source.
Better batteries through biology?
25 November 2013
Lithium-air batteries have become a hot research area in recent years: They hold the promise of drastically increasing power per battery weight, which could lead, for example, to electric cars with a much greater driving range. But bringing that promise to reality has faced a number of challenges, including the need to develop better, more durable materials for the batteries' electrodes and improving the number of charging-discharging cycles the batteries can withstand.
Now, MIT researchers have found that adding genetically modified viruses to the production of nanowires — wires that are about the width of a red blood cell, and which can serve as one of a battery's electrodes — could help solve some of these problems.The key to their work was to increase the surface area of the wire, thus increasing the area where electrochemical activity takes place during charging or discharging of the battery.
The researchers produced an array of nanowires, each about 80 nanometers across, using a genetically modified virus called M13, which can capture molecules of metals from water and bind them into structural shapes. In this case, wires of manganese oxide — a "favorite material" for a lithium-air battery's cathode, Belcher says — were actually made by the viruses. But unlike wires "grown" through conventional chemical methods, these virus-built nanowires have a rough, spiky surface, which dramatically increases their surface area.
Belcher, the W.M. Keck Professor of Energy and a member of MIT's Koch Institute for Integrative Cancer Research, explains that this process of biosynthesis is "really similar to how an abalone grows its shell" — in that case, by collecting calcium from seawater and depositing it into a solid, linked structure.
The increase in surface area produced by this method can provide "a big advantage," Belcher says, in lithium-air batteries' rate of charging and discharging. But the process also has other potential advantages, she says: Unlike conventional fabrication methods, which involve energy-intensive high temperatures and hazardous chemicals, this process can be carried out at room temperature using a water-based process.
Also, rather than isolated wires, the viruses naturally produce a three-dimensional structure of cross-linked wires, which provides greater stability for an electrode.
A final part of the process is the addition of a small amount of a metal, such as palladium, which greatly increases the electrical conductivity of the nanowires and allows them to catalyze reactions that take place during charging and discharging. Other groups have tried to produce such batteries using pure or highly concentrated metals as the electrodes, but this new process drastically lowers how much of the expensive material is needed.
Altogether, these modifications have the potential to produce a battery that could provide two to three times greater energy density — the amount of energy that can be stored for a given weight — than today's best lithium-ion batteries, a closely related technology that is today's top contender, the researchers say.
Belcher emphasizes that this is early-stage research, and much more work is needed to produce a lithium-air battery that's viable for commercial production. This work only looked at the production of one component, the cathode; other essential parts, including the electrolyte — the ion conductor that lithium ions traverse from one of the battery's electrodes to the other — require further research to find reliable, durable materials. Also, while this material was successfully tested through 50 cycles of charging and discharging, for practical use a battery must be capable of withstanding thousands of these cycles.
While these experiments used viruses for the molecular assembly, Belcher says that once the best materials for such batteries are found and tested, actual manufacturing might be done in a different way. This has happened with past materials developed in her lab, she says: The chemistry was initially developed using biological methods, but then alternative means that were more easily scalable for industrial-scale production were substituted in the actual manufacturing.
This story is reprinted from material from MIT, with editorial changes made by Materials Today. The views expressed in this article do not necessarily represent those of Elsevier. Link to original source.


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On October 15, 1883, one hundred and eighty-nine men, mostly Union veterans of the Civil War, boarded a train in Newark, New Jersey heading for Richmond. Shortly after their arrival the next day, they attended a banquet with veterans who had served in the armies of both sides. When I discovered a menu from this dinner, oddly printed on an old Confederate banknote, I became curious about their visit to the former capital of the Confederacy.
The long and complicated process of reestablishing cordial relations between the North and South went through various phases. In March 1865, with the war nearing its completion and the Confederacy in shambles, President Lincoln set the tone for reuniting the country, counseling "malice toward none; with charity for all" in his second inaugural address. During the presidential campaign in 1868, General Ulysses S. Grant promoted the idea of reconciliation with the words "Let There Be Peace," the slogan by which he would be most remembered. By the early 1880s, there was a growing awareness among northern veterans that there had been two sides in the conflict. Reflecting this change in perception, the Gettysburg Battlefield Memorial Association (responsible for erecting monuments and preserving the site) came to the conclusion in 1882 that it was meaningless to mark the Union lines without knowing the Rebel positions. Accordingly, they invited former Confederate officers to visit the field and show them where their troops had been positioned. In another gesture of reconciliation that year, the Grand Army of the Republic (G.A.R.), the largest national organization of Union veterans, marched together with Confederate veterans in a commemorative parade.
These widely-reported events may have encouraged the Union veterans of Lincoln Post No. 11 in Newark to embark on their goodwill mission to Richmond in 1883. As one of its members later recalled, "It had been eighteen years since the end of the war, yet, little had been done of a personal, practical character to heal up the old sores and make the body politic whole and healthy again."1 On the night of their departure, the so-called "brigade" marched down Market Street amidst the cheers of well-wishers, guided to the railroad depot by a blaze of electric lights—a new technological development.2 The scene was further illuminated by Roman candles being ignited from the rooftops and colorful bonfires radiating red, white, and blue. The hubbub continued until the train pulled out of the station, bringing the handshaking and god-speeds to an end. After months of preparation, they were finally on their way.3
Pennsylvania & Potomac Station |
Ford's Hotel, ca. 1882 |
Two local veterans' organizations, one Union and the other Confederate, co-hosted the visitors from New Jersey. Veterans of the Civil War typically harbored no feelings of animosity toward those who had fought on the other side. In fact, they would often go over to shake hands when they spotted their former enemies visiting a battlefield at the same time. Still, the "Jerseymen" were surprised to see how closely these two groups in Richmond worked together, even to the point of holding their meetings in the same room, randomly decorated with Confederate and Union flags.4
The banquet was to be held in Saenger Halle, a nearby meeting hall and saloon that was large enough to accommodate all three hundred of the participants. While they were resting and waiting for dinner, a quick look at the hotel's bill of fare would have given the visitors a general idea of what they might expect that evening. Dating from the previous year, the daily menu below from Ford's Hotel features local foods like corned pork and turnips, barbecued shoat (weaned young pig), ox heart stuffed with barbecue sauce, small patties of veal brains, and turkey "pinons" (wings) with oyster sauce. The baked chub, possibly one of any number of unrelated fish, may have been a tautog, a blackfish found off the coast of southeast Virginia.
At 9:00 PM on October 16, 1883, the visitors marched a few blocks over to the banquet hall where they found the entire room (including the stage at the end) filled with tables laden with food, and the unusual menus printed on old Confederate banknotes. Interestingly, the one shown below is printed on a ten-dollar bill, showing a unit of field artillery moving at full speed, the only Confederate note of the seventy-two different types of paper money printed during the war that depicted soldiers. In what may have been another surprise, their hosts waited on the tables themselves—the Union men from the Phil Kearney Post No. 11, working alongside the former Confederates from Robert E. Lee Camp No. 1, formed a corps of waiters, serving their guests with "royal munificence." After about an hour, the clatter of Army knives and forks died down, the time having come for the speeches and presentations. One of the biggest hits of the evening was the return of a pair of saddlebags to their original owner, the trophy having been captured by Union forces at the Battle of Sayler's Creek in the final days of the war.5 After the formalities were completed, the "friends," as they now called each other, finished the evening toasting one another with "bumpers of punch, lusty and toothsome," while the band played "Dixie," "Yankee Doodle," and "Columbia, the Gem of the Ocean."
The bill of fare transcribed below features dishes that are more conventional than some of the ones on the menu at Ford's Hotel in 1882, except for the shoat, the roasted young pigs perhaps being a local specialty.
The menus printed on Confederate currency were not as unique as they may have appeared to the visiting Yankees. In the years following the war, local entrepreneurs discovered that the old notes were an attention-grabbing novelty, as shown by this ten-dollar bill with an advertisement for Ford's Hotel, similar in appearance to the menu.
All the same, the old banknotes may have meant something more to the visiting veterans than just a mere souvenir. No longer legal tender (not that they ever were), the obsolete paper money was now ephemera—the minor historical documents of everyday life that provided tangible evidence of the rebellion and the desperate struggle in which they had been engaged. Even Abraham Lincoln seems to have found the currency strangely compelling. After he was assassinated in April 1865, a five-dollar Confederate bill was found in his pockets, perhaps a memento that he received during his trip to Richmond ten days earlier, immediately following the evacuation of the city by Confederate forces. (The saddlebags were picked up at Sayler's Creek the day after Lincoln's visit.)
During their two-day visit, the men from New Jersey toured the local sights, such as the tobacco warehouses, St. John's Church where Patrick Henry proclaimed, "Give me liberty or give me death," and the Allan mansion where Edgar Allan Poe was "reared." They also walked around the former military prisons and battlefields, looking for "relics," as they called the small objects still scattered on the battlegrounds. However, the veterans mostly visited the cemeteries that ringed the city, taking time to honor the dead of both sides, for the experience of the war had not stopped for these men when the shooting ended; they continued to live with their war.
Nevertheless, the men had grown disheartened by the time they were getting ready to leave Richmond, for they had seen no national flags during their visit (except for the one flying over their hotel), nor had the citizens come out to cheer their parades. Indeed, they came to believe that they were not really welcome in the city, even though the mayor tried to convince them otherwise when they first arrived, explaining in his welcoming speech that it was not the local custom to display flags, nor was it part of southern etiquette to witness parades. Even their commander attempted to alleviate such feelings, reassuring them that they would have won over the local people, if only they had been able to stay one more day. Yet, despite such well-intended explanations, it was true; in contrast to the warm reception they received from their fellow veterans, the visitors had been shunned by much of the white population, a group then representing about 58% of the 65,000 people who lived in the city. Despite their good intentions, the Union veterans wondered whether their trip had done any good; only time would tell whether they had helped, in some small way, to bring the country back together.
When President Grant died two years later, his widow Julia Grant did her part in the reconciliation effort, asking several Confederate generals to serve as pallbearers. Mrs. Jefferson Davis, wife of the former president of the Confederacy, and by then a friend of Julia Grant's, did her part too, writing a touching eulogy to Grant that was reprinted in Northern papers. During the Memorial Day observances in New York the following year in 1886, over twenty thousand people visited Grant's tomb, his burial site covered by a mountain of flowers sent from all over the country.6 Amidst the profusion of floral displays, one item attracted particular attention. Standing next to an arrangement of white and red roses, made by the pupils of the grammar school in Sacramento, California, was a large container with a small cypress tree surrounded by smaller plants. Decorated with blue and gray ribbons, the inscription on it read, "Let us have peace. From R. E. Lee Camp of Confederate Veterans, Richmond, Va."
1. Henry Benson, "Yank" and "Reb"; a history of a fraternal visit paid by Lincoln Post, No. 11, G. A. R., of Newark, N. J. to Robt. E. Lee Camp, No. 1, Confederate Veterans and Phil. Kearney Post No. 10, G. A. R. of Richmond, Va., October 15th, to October 18th, inclusive, Newark, New Jersey, 1884.
2. Thomas Edison began his career as an inventor in Newark before moving his home and laboratory to Menlo Park, twenty miles south of the city. After patenting a system for electricity distribution in 1880, he founded the Edison Illuminating Company, switching on its first generating station on September 4, 1882 to serve fifty-nine customers in lower Manhattan.
3. On the same day in October 1883, the Supreme Court ruled that the Civil Rights Act was unconstitutional. Signed into law by President Grant in 1875, the act guaranteed that everyone, regardless of race, color, or previous condition of servitude, was entitled to "the full and equal enjoyment" of public accommodations such as hotels, transportation, theaters, and other amusement places. It was rarely enforced, especially after the 1876 presidential election that resulted in the withdrawal of federal troops from the South, effectively ending the Reconstruction era.
4. Robert E. Lee Camp, No. 1, Confederate Veterans, was just getting started in 1883. Having met for the first time on April 18 of that year, the benevolent society was formed by veterans to aid their financially needy, often disabled, comrades. It was one of the first such veterans organizations formed in the South. After incorporating in 1884, they opened a soldiers' home on an old farm in the west end of Richmond (now the corner of Grove Avenue and the Boulevard) on January 1, 1885.
5. The Battle of Sayler's Creek (now also known as Sailor's Creek) was fought on April 6, 1865, southwest of Petersburg, Virginia, three days before General Lee surrendered at Appomattox Court House.
6. New York Times, 1 June 1886. See Dry Monopole by Half a Length (11 April 2011) for another reference to the Memorial Day observances in New York City in 1886.

subset: commoncrawl


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Umineko WHEN THEY CRY Episode 1
Legend of the Golden Witch, Vol. 2
By Ryukishi07; Kei Natsumi (Artist)
(Yen Press, Paperback, 9780316229500, 624pp.)
Publication Date: February 26, 2013
Other Editions of This Title: Paperback, Paperback, Paperback, Paperback, Paperback
Categories: Manga - Horror
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Six people are dead, and Battler and his remaining relatives slowly come around to addressing the terrifying reality of their situation: Either one of their number is a murderer, or there is a nineteenth person on the island who wants the Ushiromiya family dead. Regardless, the killer seems to be following the inscription beneath the portrait of Beatrice, the instructions for finding the elder Ushiromiya's vast treasure of gold. But each line of the inscription calls for more death, more blood...and the revival of the witch Beatrice herself... Will any remain alive to see the end of this mystery?
Ryukishi07 leapt into the spotlight with HIGURASHI NO NAKU KORO NI which was originally conceived as a series of visual novels and later adapted into the popular manga and anime franchise.


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The Mount Snow Valley towns of Wilmington and Dover are working together and independently on economic development plans aimed at improving the quality of life of residents, employers, and visitors to our area.
The Mount Snow Valley Chamber of Commerce is committed to the efforts put forth by these two emerging groups:
Dover Economic Development Committee - The Dover Economic Development Committee (often referred to as the "DEDC") was created by mandate of the voters in Dover at the 2007 Town Meeting. This group advocated for passage of a 1% tax to be dedicated to economic development and improving and enhancing the quality of life in Dover for residents and visitors alike. There November 2007 progress report to the Dover select board can be read here
Following the flood resulting from hurricane Irene, the town of Wilmington and the Bi-Town committee have again united to work on Long Term Community Recovery for economic development. Begun with FEMA assistance this process continues with the work of over 30 committees tasked with developing needed projects to ensure Long Term Recovery. As these reports become public records we will post them here for public review.
Additionally the Mount Snow Valley Chamber is actively working with the Brattleboro Development Corporation to secure funding under the Economic Development Agency grant process.
For a historic perspective on the economic developments of recent years you may browse the documents below.
Click here to download DEDC survey results
Click here for the TriTown 2009 Proposal
Click Here for the summary from the Tri-Town's four community forums


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My husband and I stayed here over a long weekend in November 2013. We had a prestige room with an amazing view of Mont Saint-Michel. The room was clean and functional, and the bed was comfortable, but lacked a kettle with coffee or tea, which is something expected in a 4-star hotel. Standards are a little different from country to... More
- Also Known As:
- Le Relais Saint-Michel Hotel
- Le Relais Saint-Michel Hotel Mont-St-Michel
- Official Description (provided by the hotel):
- Overlooking the Mont Saint Michel, the 8th Marvel of the World, the Relais Saint Michel is a **** hotel, offering you a panoramic restaurant, terraces, flower gardens, a piano bar and spaces for relaxation. ... more less
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- TripAdvisor is proud to partner with Booking.com, Expedia, Priceline, Hotels.com, Otel, Cheap Tickets, Orbitz, Agoda and Tingo so you can book your Le Relais Saint-Michel reservations with confidence. We help millions of travellers each month to find the perfect hotel for both holiday and business trips, always with the best discounts and special offers.


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tomorrow and tomorrow and tomorrow...
... I promised an essay today. It will be coming either later today or tomorrow morning. Also, it won't be on the promised topic. I know I'm beginning to sound like the Monty Python restaurant that--what was it?--has nothing on offer to eat, but about the topic, at least, I have this excuse:
Douglas McClennan, the lovely and incredibly hardworking founder and main force behind Arts Journal, advised me when we were planning this blog to stay flexible. Don't stick with the scheduled topic simply because you planned on it, he said. Given that this is a public forum, if the conversation takes a particular turn go with it.
So the bit on new takes on old story ballets--when the variation works, when not, what's the criterion for its success or failure--will hold till next week (or the week after that, if something else comes up) because with my very first sentence, I landed smack at the troublesome center of writing about "dance," and thought I ought to try to extricate myself--and us?--before proceeding.
In the meantime, read this brilliant and hilarious post on rhythm, from friend and colleague Paul Parish, of Berkeley. He is responding to choreographer-director Annie-B Parson' post below.
Here's Paul:
...Well, what I meant was that rhythm is what separates us from OTHER animals. We are not the only animal that dances -- though our nearest relations (the chimpanzees) don't seem to, and dancing seems to be maybe THE thing that allows us to live in larger groups than other apes can sustain before they start killing each other off.
Other animals are usually wonderfully co-ordinated as individuals (though I know an old Labrador who walks with a sad arthritic gait), and they can certainly move in groups in fluid and fascinating ways, but even birds don't move in really rhythmic ways (except when there's wind-pressure to obey).
Obviously we disagree on the meaning of rhythm - I'm being rather strict. I think by your definition, gymnasts would have rhythm, but really they just obey the requirements of their separate tricks and create the best flow of movement they can from one movement to the next -- as a horse would do in dressage or in a stampede.
Some football players have rhythm, but they really only become rhythmic when they break into the cakewalk in order to cross the goal-line.
We're not talking about counts, a tango and a fox-trot have very similar counts but the push-pull of the rhythm is really different. Indeed, the habanera and the tango have identical counts but the push-pull is different.
As for unison, that's a theoretical term, it appeals to the cortex. It's certainly an interesting question, how does a dance company find a unison? My friends at Axis dis/Abled Dance Company have found a fascinating solution to it. But what I'm talking about is pre-verbal (human beings I'd bet were dancing before we were talking; it's deeper in our animal natures). I'm talking about a beat or a groove, and that's I think what it takes to get the casual observer to identify with dancers for the long haul.
Rhythm, I think, is what allows him to tune in and then once the actual frequency is established -- as in radio frequency -- the choreographer can modulate it. I think that's how Mark Morris gets us to tune into his weird projects -- he just GOES RIGHT THERE, and the next thing you know, you're in there, and the rhythm makes an unlikely prospect -- such as a staged oratorio -- turn into something that makes the people who were there feel like "we lucky few; we're the only ones who will ever know how fantastic that was....."
Many things will engage the interest briefly; falling is very exciting, turning is too, esp if it looks like the dancer MAY FALL. But the only way to get someone deeply interested is through the rhythm.
I certainly do agree it's true, how good the rhythm is IS a measure of how good the choreographer is.
addendum: Did you know "strangers in the night" is a tango, and "stand by me" a cha cha? Indeed, jingle bells is a polka.... nobody ever thinks that's important, but I saw my grandmother dance with santa claus when she was 80 while we all sang Jingle Bells and she did a KICK on Hey (in a one-horse open sleigh, HEY, jingle bells) and it opened MY eyes...... Oh, she was a great lady. My God!
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allaboutmykids writes:
ummmm....first of all Zimba....is basically Simba. and Simba was the Lion on The Lion King. not a very original name actually.
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I hope that everyone has a happy and safe holiday! Next year our little ones will be here to celebrate with us (Think of the adorable photo ops!).
I'm doing my best to keep DS distracted, so we'll be off to the movies in a bit. Right now I'm crying over the Norad tracking Santa app. Gotta love pregnancy hormones. DH said I'm just a ball of estrogen these days :-)
TTC Baby Rob #1 05/07, BFP 06/07, EDD 02/22/08, Baby Jackaroo born via c-section after 22 hours of labor on 02/27/08
TTC Baby Rob #2 06/11 BFP 11/06/11 EDD 07/16/12 Natural M/C 11/25/11 @ 6w3d
Baby Rob #2 (Sloane), in our hearts always.
Here comes Baby Rob #3
BFP on Cycle 17 09/27/12. EDD 06/04/12! Please Stick Baby! A/S 01/22/13 Baby looking great. Officially TEAM BLUE! Jack is getting a Baby Brother! RCS scheduled for 05/29/13. William Daryll born at 9:59am on 05/29/13. Left ovary and tube removed due to peach sized tumor found during RCS. Pathology came back benign!


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Vuvuzela hurting World Cup experience
by Eric SchwartzI had a bad experience today.
While doing some yard work I came upon a bees nest. Wisely I chose to stay away from the nest, doing my best to avoid any type of swarm coming at my face. Yet despite my best efforts, the bees came charging, buzzing around my face for what seemed like hours. The annoyance of the whole event goes beyond words.
OK, truthfully that event never happened.
Instead I simply turned on the World Cup.
Anyone who has experienced even a minute of the World Cup can emphasize with what I am speaking of. The host South Africans don't chant, don't cheer, don't sing. Instead they play a horn known as the vuvuzela. And they play it all game. Every game.
I'm hardly the first blogger or reporter to write about this. The vuvuzela has been talked about as much as England goalkeeper Robert Green these days. In fact I'm not sure which issue the English are angrier with right now.
Players haven't commented much on the horns but there have been reports that the decibel rating in the stadium is enough to damage your hearing. I'm not sure I buy that, though. South African fans have been doing it for years and I don't see any of the players wearing earplugs.
The President of FIFA recently came out and said he would not ban vuvuzela playing from the stadiums and I have to support his decision. If it's a big ritual in South African culture, then who is he, I, or anyone else to tell them to stop playing?
That doesn't mean that this whole vuvuzela thing doesn't grind my gears though. I mean don't these people have to stop to take a breath once in awhile?
When I tuned into the first World Cup game on Friday I noticed the horn playing but thought, like any other background noise, it would simply go away. The problem is it hasn't.
One of the great things about soccer is the passion of the fans. I love the cheering and the chanting. It's what helps make the sport so beloved around the world (even if not in the U.S.).
During this World Cup we get none of that.
It's funny how much things change in a couple of weeks. Suddenly I long for the "Ole, Ole, Ole, Ole" chant again (as long as it's not coming from the Canadiens, that is).
Go figure.
2 Responses to "Vuvuzela hurting World Cup experience"
Ryan on
June 15th, 2010 7:27 pm
i love it haha
Doug on
June 16th, 2010 12:33 pm
What I can't hear you lol
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Updated: 6:23 p.m. Saturday, May 30, 2009 | Posted: 10:31 a.m. Saturday, May 30, 2009
SPRINGFIELD, Ohio —
An argument escalated near the Knights of Pythias Club on Yellow Springs Street just hours after another member of the private club was wheeled out on a stretcher.
Neighbors said they heard the gunshots erupt from the club which police said is a relatively calm, social place which tries to keep the violence down.
Springfield Police Chief Steve Moody said people in the club were trying to get a man to leave around 1:30 a.m. Shortly after, there was a confrontation between an individual and someone else at the doorway when a man produced a gun and started firing.
Moody said when officers arrived they found two individuals down in the club, both wounded by gunfire.
Police said the suspect shot and killed 35-year-old William Lewis, hitting him in the neck and arm. The shooter then followed another victim outside to shoot him again.
The shooting is still being investigating by the police who said the K of P Club is not one of their usual trouble spots.
"This club works with us in the community to try to talk about problems they have," Moody said. "They try to be vigilant about keeping problems down and they were trying to be vigilant today."
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Photography is a way of feeling, of touching, of loving. It is an image you have captured forever . . . it remembers little things, long after you have forgotten everything.
i am wondering what the photo was when you took it, just the water and you added the rest? i would love to have an ipad