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A method for producing compound semiconductor quantum particles from at least a metallic element selected from Groups IIA, IIB, IIIA, IVA, and VA of the Periodic Table and at least a non-oxygen reactant element selected from the group consisting of P, As, S, Se, and Te. The method includes: (a) operating a heating and atomizing means to provide a stream of super-heated fine-sized fluid droplets of a selected metallic element into a reaction chamber; (b) directing a stream of a reactant element-containing fluid medium into the chamber to impinge upon and react with the super-heated metal fluid droplets to form substantially nanometer-sized phosphide, arsenide, sulfide, selenide, and/or telluride compound particles; and (c) cooling and/or passivating the compound particles to form the desired compound semiconductor quantum particles. These quantum particles are particularly useful for photo luminescence and biological labeling applications.
1. A method for producing compound semiconductor quantum particles from at least a metallic element selected from Groups IIA, IIB, IIIA, IVA, and VA of the Periodic Table and at least a non-oxygen reactant element selected from the group consisting of P, As, S, Se, and Te, said method comprising:
(a) operating a heating and atomizing means to provide a stream of super-heated fine-sized fluid droplets of said at least a metallic element into a reaction chamber;
(b) directing a stream of a reactant fluid medium comprising said at least a reactant element into said chamber to impinge upon and react with said stream of super-heated metal fluid droplets to form substantially nanometer-sized phosphide, arsenide, sulfide, selenide, and/or telluride compound particles; and
(c) cooling and/or passivating said compound particles to form said compound semiconductor quantum particles in a solid state.
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17. A method for producing compound semiconductor quantum particles from at least a metallic element selected from Groups IIA, IIB, IIIA, IVA, and VA of the Periodic Table and at least a non-oxygen reactant element selected from the group consisting of P, As, S, Se, and Te, said method comprising:
(a) operating a heating means to generate super-heated fluid droplets of said at least a metallic element in a reaction chamber;
(b) directing a stream of a reactant fluid-medium comprising said at least a reactant element into said chamber to concurrently atomize and react with said super-heated metal fluid droplets to form substantially nanometer-sized phosphide, arsenide, sulfide, selenide, and/or telluride compound semiconductor particles; and
(c) cooling and/or passivating said compound particles to form said compound semiconductor quantum particles in a solid state.
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The present invention is a result of a research sponsored by the SBIR Program of U.S. National Science Foundation. The U.S. government has certain rights on this invention.
The present invention relates to a method for producing nanometer-sized semiconductor particles, and more particularly, it relates to a method for producing quantum-sized compound semiconductor particles (diameter smaller than 20 nm or 200 Å) at a high production rate.
Nanometer-sized semiconductor crystallites or "quantum dots" whose radii are smaller than the bulk exciton Bohr diameter (up to 20 nm, but normally smaller than 10 nm in radius) represent a class of materials intermediate between molecular and bulk forms of matter. Quantum confinement of both the electron and hole in all three dimensions leads to an increase in the effective band gap of the semiconductor-material with decreasing crystallite size. As a result, both the optical absorption and emission of quantum dots shift to the higher energies (blue shift) as the size of the dots gets smaller. Nanometer-sized semiconductor crystallites that show such a quantum size effect are also referred to as quantum-sized crystals. They include I-VII, II-VI, III-V, III-VI and IV-VI compound semiconductors. As compared to I-VII and II-VI groups, the III-V semiconductor nano crystals have been studied to a lesser extent possibly due to the numerous difficulties encountered in the preparation of this class of nano crystals. However, as compared to the I-VII and I-VI semiconductors, the III-V materials have a greater degree of covalent bonding, a less ionic lattice, and larger exciton diameters (e.g., the exciton diameter in GaAs is 19 nm, compared to 6 nm for CdS). For this reason, the quantum size effect on the optical spectra has been predicted to be more pronounced in the III-V class of materials than in the II-VIs.
Quantum-sized compound semiconductors have been found to provide an electro-luminescent device capable of emitting light of various visible wavelengths in response to, external stimulus. In such an electro-luminescent device, variations in voltage could result in change of color of the light emitted by the device. Since these three classes of light emitting materials are inorganic materials, they are capable of withstanding higher temperatures than the conventional organic polymeric materials for light-emitting applications.
Fluorescent labeling of biological systems is a well known analytical tool used in modern biotechnology as well as analytical chemistry. Applications for such fluorescent labeling include technologies such as medical fluorescence microscopy, histology, flow cytometry, fluorescence in-situ hybridization for medical assays and research, DNA sequencing, immuno-assays, binding assays, separation, etc. Quantum-sized semiconductor crystals have been found to provide stable probe materials for biological applications having a wide absorption band. These crystals are capable of exhibiting either a detectable change in absorption or of emitting radiation in a narrow wavelength band, without the presence of the large red emission tails characteristic of dye molecules. This feature makes it possible to permit the simultaneous use of a number of such probe materials, each emitting light of a different narrow wavelength band and/or being capable of scattering or diffracting radiation. These stable probe materials can be used to image the same sample by both light and electron microscopy.
The following patents are believed to represent the state of the art of semiconductor quantum particles:
1. S. Weiss, et al., "Semiconductor nanocrystal probes for biological applications and process for making and using such probes," U.S. Pat. No. 6,207,392 (Mar. 27, 2001).
2. A. P. Alivisatos, et al., "Process for forming shaped group II-VI semiconductor nanocrystals, and product formed using process," U.S. Pat. No. 6,225,198 (May 1, 2001).
3. A. P. Alivisatos, et.al., "Preparation of III-V semiconductor Nanocrystals," U.S. Pat. No. 5,505,928 (Apr. 9, 1996).
4. A. P. Alivestos, et al., "Electroluminescent devices formed using semiconductor nanocrystals and an electron transport media and method of making such electroluminiscent devices," U.S. Pat. No. 5,537,000 (Jul. 16, 1996).
5. S. Weiss, et al., "Organic luminiscent semiconductor nanocrystal probes for biological applications and process for making and using such probes," U.S. Pat. No. 5,990,479 (Nov. 23, 1999).
6. A. P. Alivestos, et al., "Semiconductor nanocrystals covalently bound to solid inorganic surfaces using self-assembled monolayers," U.S. Pat. No. 5,751,018 (May 12, 1998).
7. M. G. Bawendi, et al., "Water-soluble fluorescent nanocrystals," U.S. Pat. No. 6,251,303 (Jun. 26, 2001).
8. M. G. Bawendi, et al., "Highly luminescent color-selective materials and method of making thereof," U.S. Pat. No. 6,207,229 (Mar. 27, 2001).
9. N. M. Lawandy, "Semiconductor nanocrystal display materials and display apparatus employing same," U.S. Pat. No. 5,882,779 (Mar. 16, 1999).
10. A. L. Huston, "Glass matrix doped with activated luminiscent nanocrystalline particles," U.S. Pat. No. 5,585,640 (Dec. 17, 1996).
11. H. F. Gray, et al. "Nanoparticle phosphors manufactured using the bicontinuous cubic phase process," U.S. Pat. No. 6,090,200 (Jul. 18, 2000).
12. J. Yang, "Formation of nanocrystalline semiconductor particles within a bicontinuous cubic phase," U.S. Pat. No. 6,106,609 (Aug. 22, 2000).
13. S. L. Castro, et al., "Functionalized nanocrystals and their use in detection systems," U.S. Pat. No. 6,114,038 (Sep. 5, 2000).
14. E. Barbera-Guillem, "Lipophilic, functionalized nanocrystals and their use for fluorescence labeling of membranes," U.S. Pat. No. 6,194,213 (Feb. 27, 2001).
15. D. Gallagher, et al., "Method of manufacturing encapsulated doped particles," U.S. Pat. No. 5,525,377 (Jun. 11, 1996).
16. C. Lawton, "Biomolecular synthesis of quantum dot composites," U.S. Pat. No. 5,985,353 (Nov. 16, 1999).
17. O. Siiman, et al., "Semiconductor nanoparticles for analysis of blood cell populations and method of making same," U.S. Pat. No. 6,235.,540 (May 22, 2001).
18. J. C. Linehan, et al. "Process of forming compounds using reverse micelle for reverse microemulsion systems," U.S. Pat. No. 5,770,172 (Jun. 23, 1998).
Bawendi and co-workers have described a method of preparing monodisperse semiconductor nanocrystallites by pyrolysis of organometallic reagents injected into a hot coordinating solvent [Ref.8]. This permits temporally discrete nucleation and results in the controlled growth of macroscopic quantities of nanocrystallites. Size selective precipitation of the crystallites from the growth solution provides crystallites with narrow size distributions. The narrow size distribution of the quantum dots allows the possibility of light emission in very narrow spectral widths. Although semiconductor nanocrystallites prepared as described by Bawendi and co-workers exhibit near monodispersity, and hence, high color selectivity, the luminescence properties of the crystallites are poor. Such crystallites exhibit low photoluminescent yield, that is, the light emitted upon irradiation is of low intensity. This is due to energy levels at the surface of the crystallite which lie within the energetically forbidden gap of the bulk interior. These surface energy states act as traps for electrons and holes which degrade the luminescence properties of the material.
Since mid-1980's, various synthetic approaches have been developed in preparing nano-sized II-VI (Zn and Cd chalcogenides) and IV—VI (Pb chalcogenides) semiconductors. Much of this effort has been aimed at achieving a very narrow particle size distribution. The basic idea is to use the spatial or chemical confinement provided by matrices or organic capping molecules to terminate the growth of nanocrystallites at any desired stage. In most cases, lack of a microscopically uniform environment in the substrates might be the cause for relatively wide size distribution. Both organic and inorganic matrices, such as monolayers, polymers, inverse micelles, and zeolites have been used to control the particle size. Recently, other researchers have obtained mono-dispersed CdSe nano crystallites based on the pyrolysis of organometallic reagents. This approach makes use of the concept of Ostwald ripening for size selective precipitation of nano crystallites. So far, many efforts have been made to synthesize quantum-sized II-VI semiconductors especially on the CdSx�Se1−x systems, while much fewer efforts on IV—VI (PbX, X=S, Se, Te) compounds have been reported. The IV—VI group of compound semiconductors exhibits smaller band gaps, greater quantum-size effect and larger optical non-linearity compared to II-VI materials.
Conventional wet chemistry synthesis performed without matrix assistance tends to result in the production of micron size particles. Various host matrices, such as glass, zeolites, sol-gels, and micelles, have been used to synthesize nano particles. However, a number of problems have been found to be associated with these methods. For instance, the particles synthesized in glasses and sol-gels exhibit large polydispersity, since they are not ordered structures. Another disadvantage with these methods is the inability to easily isolate the nano particles from the matrix material. In the case of micelles, even though it is possible to isolate the particles, the low precursor concentrations required will make mass production of nano particles expensive or impractical.
Semiconductor nano crystals, such as Group II-VI nano crystals may be formed by dissolving a Group II precursor and a Group VI precursor in a solvent and then applying heat to the resulting solution. For example, Group II-VI semiconductor nano crystals may be formed by dissolving a dialkyl of the Group II metal and a Group VI powder in a trialkyl phosphine solvent at ambient temperature, and then injecting the mixture into a heated (340�-360� C.) bath of tri-octyl phosphine oxide (TOPO). While the above process is capable of producing Group II-VI semiconductor nano crystals, the results can be somewhat erratic in terms of average particle size and size distribution. This problem of not being reproducible is likely due to the impurities in the technical grade (90% pure) TOPO that adversely influence the reaction. However, substitution of pure TOPO for the technical grade TOPO has also been unsatisfactory, particularly when control of the shape of the particle growth is also desired, clearly because the pure TOPO binds too weakly to the growing crystallites and only weakly associates with the Group II metal to act as a growth retardant, resulting in the growth of spheres rather than any other desired shapes. It seems that the presence of impurities in the technical grade TOPO results in the erratic success of Group II-VI semiconductor nanocrystal growth in technical grade TOPO.
Alivisatos et al. [Ref.3] describes a process for forming Group III-V semiconductor nano crystals wherein size control is achieved through use of a crystallite growth terminator which controls the size of the growing crystals. Crystallite growth terminators are said to include a nitrogen-containing or a phosphorus-containing polar organic solvent having an unshared pair of electrons. The patent further states that this growth terminator can complex with the metal and bind to it, thereby presenting a surface which will prevent further crystal growth.
Since various groups of compound semiconductor nano crystals are of interest for use in optical displays, as well as in biological applications, it would be desirable to provide a process for mass-producing these semiconductor nano crystals wherein the particle size, growth rate, and particle size distribution can be reproducibly controlled.
The techniques for the generation of nanometer-sized particles may be divided into three broad categories: vacuum, gas-phase, and condensed-phase synthesis. Vacuum synthesis techniques include sputtering, laser ablation, and liquid-metal ion sources. Gas-phase synthesis includes inert gas condensation, oven sources (for direct evaporation into a gas to produce an aerosol or smoke of clusters), laser-induced vaporization, laser pyrolysis, flame hydrolysis, and combustion synthesis. Condensed-phase synthesis includes reduction of metal ions in an acidic aqueous solution, liquid phase precipitation of semiconductor clusters, and decomposition-precipitation of ionic materials for ceramic clusters. Other methods include high-energy milling, mix-alloy processing, chemical vapor deposition (CVD), and sol-gel techniques.
All of these techniques have one or more of the following problems or shortcomings:
(1) Most of these prior-art techniques suffer from a severe drawback: extremely low production rates. It is not unusual to find a production rate of several grams a day. Vacuum sputtering, for instance, only produces small amounts of particles at a time. Laser ablation and laser-assisted chemical vapor deposition techniques are well-known to be excessively slow processes. The high-energy ball milling method, known to be a "quantity" process, is capable of producing only several kilograms of nano-scaled powders in approximately 100 hours. These low production rates, resulting in high product costs, have severely limited the utility value of nano-phase materials. There is, therefore, a clear need for a faster, more cost-effective method for preparing nanometer-sized powder materials.
(2) Condensed-phase synthesis such as direct reaction of metallic element with a reactant to produce compound semiconductor powder requires pre-production of metallic element of high purity in finely powdered form. This reaction tends to produce a compound powder product which is constituted of a broad particle size distribution. Furthermore, this particular reaction does not yield a product powder finer than 100 nm (nanometers) except with great difficulty. Due to the limited availability of pure metallic element in finely powdered form, the use of an impure metallic powder necessarily leads to an impure compound semiconductor product.
(3) Some processes require expensive precursor materials to semiconductor powders and could result in harmful by-product that has to be properly disposed of.
(4) Most of the prior-art processes are capable of producing a particular type of compound powder at a time, but do not permit the preparation of a uniform mixture of two or more types of nano-scaled ceramic powders at a predetermined proportion.
(5) Most of the prior-art processes require heavy and/or expensive equipment (e.g., a high power laser source and high vacuum equipment), resulting in high production costs. In the precipitation of ultra fine particles from the vapor phase, when using thermal plasmas or laser beams as energy sources, the particle sizes and size distribution cannot be precisely controlled. Also, the reaction conditions usually lead to a broad particle size distribution as well as the appearance of individual particles having diameters that are multiples of the average particle size.
(6) The conventional mechanical attrition and grinding processes have the disadvantages that powders can only be produced up to a certain fineness and with relatively broad particle-size distribution. As a matter of fact, with the currently familiar large-scale process for manufacturing powders it is rarely possible, or only possible with considerable difficulty, to produce powders having average particle sizes of less than 0.5 μm (microns).
A relatively effective technique for producing fine metal particles is atomization. Atomization involves the breakup of a liquid into small droplets, usually in a high-speed jet. The breakup of a liquid stream by the impingement of high-pressure jets of water or gas is referred to as water or gas atomization, respectively. Other commonly used atomization techniques include centrifugal atomization, vacuum atomization, and ultrasonic atomization. By judiciously varying the parameters of the atomization process, the particle size, particle size distribution, particle shape, chemical composition and micro-structure of the particles can be varied to meet the requirements of a specific application.
The major components of a typical atomization system include a melting chamber (including a crucible, a heating devices and a melt-guiding pipe) in a vacuum or protective gas atmospheres an atomizing nozzle and chamber, and powder-drying (for water atomization) or cooling equipment. The metal melt can be poured into first end of a guiding pipe having a second end with a discharging nozzle. The nozzle, normally located at the base of the pipe, controls the shape and size of the metal melt stream and directs it into an atomizing chamber in which the metal stream (normally a continuous stream) is disintegrated into fine droplets by the high-speed atomizing medium, either gas or water. Liquid droplets cool and solidify as they settle down to the bottom of the atomizing chamber. This chamber may be purged with an inert gas to minimize oxidation of the powder. A subsequent collector system may be used to facilitate the separation (from the waste gas) and collection of powder particles.
When a stream of metal melt is broken up into small droplets, the total surface energy of the melt increases. This is due to the fact that the creation of a droplet necessarily generates a new surface and every surface has an intrinsic surface tension. When droplets are broken down into even smaller droplets, the total surface area of the droplets is further increased, given the same volume of material. This implies that a greater amount of energy must be consumed in creating this greater amount of surface area. Where does this energy come from? An atomizer works by transferring a portion of the kinetic energy of a high-speed atomizing medium to the fine liquid droplets. Because of the recognition that the kinetic energy (K.E.) of a medium with a mass m and velocity v is given by K.E.=� m v2, prior-art atomization technologies have emphasized the importance of raising the velocity of the atomizing medium when exiting an atomizing nozzle. In an industrial-scale atomizer jet nozzle, the maximum velocity of a jetting medium is limited, typically from 60 feet/sec to supersonic velocities. The latter high speeds can only be achieved with great difficulties, by using heavy and expensive specialty equipment. In most of the cases, low atomizing medium speeds led to excessively large powder particles (micron sizes or larger).
The effect of temperature on the surface tension of metal melt droplets has been largely overlooked in the prior-art atomization technologies. Hitherto, the metal melts to be atomized for the purpose of producing fine metal powders have been typically super-heated to a temperature higher than the corresponding melting point by an amount of 70 to 300� C. (135 to 572� F.); e.g., as indicated in U.S. Pat. No. 5,863,618 (Jan. 26, 1999) issued to Jarosinsky, et al. It is important to recognize that the higher the metal melt temperature is the lower its surface tension. A metal melt at a temperature near its vaporization point has a critically small surface tension (almost zero). This implies that a highly super-heated metal melt can be readily atomized to nanometer-scaled droplets without requiring a high atomizing medium speed. Prior-art technologies have not taken advantage of this important feature. In actuality, it is extremely difficult, if not impossible, for prior-art atomization techniques to make use of this feature for several reasons. Firstly, the vaporization temperature of a metal is typically higher than its melting temperature by one to three thousands of degrees K. The metal melt has to be super-heated to an extremely high temperature to reach a state of very low surface tension. In a traditional atomization apparatus, it is difficult to heat a bulk quantity of metal in a crucible above a temperature higher than 3,500� C. (3,773� K.), even with induction heating. Second, in a traditional atomization apparatus, the metal melt must be maintained at such a high temperature for an extended period of time prior to being introduced into an atomizer chamber. This requirement presents a great challenge as far as protection of the metal melt against oxidation (prior to atomization) is concerned since oxidation rate is, extremely high at such an elevated temperature. Third, such a high-temperature metal melt would have a great tendency to create severe erosion to the wall of the melt-guiding pipe through which the melt is introduced into an atomizer chamber. Very few materials, if any, will be able to withstand a temperature higher than 5,500� C., for example, to be selected as a guiding pipe for refractory metal melt such as tungsten and tantalum. Fourth, the operations of pouring and replenishing a crucible with metal melt implies that the traditional atomization can only be a batch process, not a continuous process and, hence, with a limited production rate.
Further, melt atomization has been employed to produce ultra fine metallic powders, but rarely for producing ceramic (including semiconductor) powders directly. This is largely due to the fact that ceramic materials such as oxides and sulfides have much higher melting temperatures as compared to their metal counterparts and require ultra-high temperature melting facilities. Therefore, ultra fine ceramic particles are usually produced by firstly preparing ultra fine base metal particles, which are then converted to the desired ceramics by a subsequent step of oxidation, sulfidation, carbonization, and nitride formation, etc. These multiple-step processes are tedious and expensive. In solution or sol-gel type processes, atomization of precursor solutions to ceramics requires an additional step of solvent removal. Furthermore, the production rates of these processes are relatively low and the final products are expensive.
Accordingly, one object of the present invention is to provide an improved method for producing quantum-size semiconductor powder materials. The method makes use of the concepts of a more effective particle kinetic energy transfer, reduced surface tension, and efficient utilization of the released reaction heat.
Another object of the present invention is to provide a method for producing a wide range of quantum-size semiconductor particles at a high production rate.
A further object of the present invention is to provide a method for producing semiconductor quantum particles that are surface-passivated.
A preferred embodiment of the present invention entails a method for producing compound semiconductor quantum particles from at least a metallic element selected from Groups IIA, IIB, IIIA, IVA, and VA of the Periodic Table and at least a non-oxygen reactant element selected from the group consisting of P, As, S, Se, and Te. The method includes: (a) operating a heating and atomizing means to provide a stream of super-heated fine-sized fluid droplets of a selected metallic element into a reaction chamber; (b) directing a stream of a reactant element-containing fluid medium into the chamber to impinge upon and react with the super-heated metal fluid droplets to form substantially nanometer-sized phosphide, arsenide, sulfide, selenide, and/or telluride compound particles; and (c) cooling and/or passivating the compound particles to form the desired compound semiconductor quantum particles. These quantum particles are particularly useful for photo luminescence and biological labeling applications.
The method begins with super-heating a molten metal to an ultra-high temperature (e.g., higher than its melting point by 1,000 to 3,000� K.) in a droplet form and operating an atomizing means to further break up the melt droplets into nanometer-sized liquid droplets. This atomizer preferably comprises a vortex jet nozzle that receives a pressurized atomizing fluid medium from a fluid medium supplier (e.g., a compressed gas cylinder) and discharges the fluid medium through an outlet (an orifice or a multiplicity of orifices) into the atomizer chamber. This outlet is preferably annular in shape and engulfing the perimeter of the stream of super-heated metal melt droplets, i.e., coaxial with the super-heated metal fluid. The pressurized fluid medium, also referred to as the atomizing medium, is introduced through the jet nozzle to impinge upon the stream of super-heated metal droplets to further atomize the melt droplets into nanometer sizes. Alternatively, the super-heat temperatures may be selected to be sufficiently high to vaporize the metal element so that the metal is in the form of isolated atoms or small clusters (preferably smaller than 40 nm in diameter and further preferably smaller than 20 nm in diameter).
These nanometer-sized metal droplets or clusters are then allowed to rapidly react with the vapor of a reactant such as phosphorus (P), arsenic (As), sulphur (S), selenium (Se), and tellurium (Te) to form compound semiconductor particles. The heat generated by such a reaction is in turn used to sustain the reaction (hence, such a reaction is hereinafter referred to as a self-sustaining or self-propagating reaction). During such a reaction, the sizes of these nano particles can be further reduced. The resulting quantum particles, in a liquid or vapor state, are rapidly cooled and/or surface-passivated with an organic or inorganic surface-coating agent and then collected as solid powders preferably in a powder classifier system that features at least a cyclone and a device for separating exhaust gases from solid particles.
The heating and atomizing means preferably includes a thermal spray device selected from the group consisting of an arc spray device, a plasma spray device, a gas combustion spray device, an induction heating spray device, a laser-assisted spray device, and combinations thereof. Further preferably, the thermal spray device is a twin-wire arc spray device. The twin-wire arc spray process, originally designed for the purpose of spray coating, can be adapted for providing a continuous stream of super-heated metal melt droplets. This is a low-cost process that is capable of readily heating up the metal wire to a temperature as high as 6,000� C. A pressurized carrier gas is introduced to break up the metal melt into fine liquid droplets or vapor clusters. In an electric arc, the metal is rapidly heated to an ultra-high temperature and is broken up essentially instantaneously. Since the wires can be continuously fed into the arc-forming zone, the arc spray is a continuous process, which means a high production rate of ultra-fine powders.
The super-heated metal liquid droplets are preferably heated to a temperature at least 1.5 times the melting point of the metal when expressed in terms of degrees Kelvin. Further preferably, the super-heated metal liquid droplets are at a temperature at least 3.0 times the melting point of the metal when expressed in terms of degrees Kelvin. This could mean a temperature as high as 6,000� C. to ensure that the metal melt has a very small surface tension or is essentially vaporized. This is readily achieved by using a thermal spray nozzle in the practice of the present invention. In contrast, in a prior-art atomizer system, it is difficult to use a furnace or induction generator to heat a crucible of metal to a temperature higher than 2,500� C.
The presently invented process is applicable to essentially all metallic materials, including pure metals and metal alloys. However, for quantum dot applications of compound semiconductor materials, the metal elements in Groups IIA, IIB, IIA, IVA, and VA of the Periodic Table are preferred substances for use in the practice of the present invention. These elements include Mg, Ca, Sr, Ba, Zn, Cd, Hg, Al, Ga, In, Ti, Ge, Sn, Pb, Sb, and Bi. The reactant elements, P, As, S, Se, or Te, alone or in combination, are directed to react with the metal droplets or clusters to form the desired compound semiconductor in an ultra-high temperature environment.
Preferably, the heating and atomizing means comprises a vortex jet nozzle for a more efficient atomization action. Preferably the atomizing fluid medium includes a noble gas such as argon or helium to provide a protective atmosphere against oxidation in the reaction chamber.
In another preferred embodiment, the method entails the utilization of a heating means to provide a super-heated metallic element (e.g., Cd) and operation of a combined atomizing and reacting means. In this case, the atomizing fluid contains the vapor of a reactant element (e.g., S or Se). The atomizing fluid not only serves to atomize the super-heated metal to form fine liquid metal droplets, but also allows the reactant element to rapidly react with the super-heated metal droplets to form quantum-size compound semiconductor-droplets (e.g., CdS or CdSe). If the atomizing fluid contains a mixture of two or more reactive gases (e.g., S and Se), the resulting product will contain a mixture of compounds (e.g., CdS, CdSe, and/or CdSxSe1−x). If the metal melt is a metal alloy or mixture (e.g., containing both Cd and Zn elements) and the reactive element is sulphur, the resulting product will contain quantum-size CdS and ZnS particles.
At the ultra-high temperature (1,000 to 2,000� K. above the metal melting point or 1.5 to 3.0 times of the melting point using absolute Kelvin scale), the surface tension of the metal melt is negligibly small and the liquid stream can be readily broken up into ultra-fine droplets. At such a high temperature, metal melt is normally capable of initiating a substantially spontaneous reaction with a reactant species (e.g., S) contained in the atomizing medium. In this case, the pressurized fluid not only possesses a sufficient kinetic energy to break up the metal melt stream into finely divided droplets, but also contains active reactant species to undergo a reaction with these fine metal droplets at high temperatures in a substantially spontaneous and self-sustaining fashion. The reaction heat released is effectively used to sustain the reactions in an already high temperature environment.
Advantages of the present invention may be summarized as follows:
1. A wide variety of quantum-sized compound semiconductor particles can be readily produced. The starting metal materials can be selected from any element in the Groups IIA, IIB, IIIA, IVA, and VA of the Periodic Table. The corresponding partner gas reactants may be selected from the group consisting of P, As, S, Se, Te and combinations thereof. No known prior-art technique is so versatile in terms of readily producing so many different types of quantum semiconductor powders.
2. The presently invented process makes use of the concept that a metal melt, when super-heated to an ultra-high temperature (e.g., reaching 1.5 to 3.0 times its melting temperature in degrees K) has a negligibly small surface tension so that a melt stream can be easily broken up into nano-scaled clusters or droplets without involving expensive or heavy atomizing nozzle equipment that is required to create an ultra-high medium speed. Prior-art atomization apparatus featuring a crucible for pouring metal melt into a melt-guiding pipe are not capable of reaching such a high super-heat temperature and/or making use of this low surface tension feature due to the four major reasons discussed earlier in the BACKGROUND section.
3. The near-zero surface tension also makes it possible to generate metal clusters of relatively uniform sizes, resulting in the formation of semiconductor powders of a narrow particle size distribution.
4. The selected super-heat temperatures also fall into the range of temperatures within which a spontaneous reaction between a metallic element and a reactant gas such as sulphur can occur. The reaction heat released is automatically used to maintain the reacting medium in a sufficiently high temperature so that the reaction can be self-sustaining until completion. The reaction between a metal and certain gas reactant (e.g., S) can rapidly produce a great amount of heat energy, which can be used to drive other reactions that occur concurrently or subsequently when other reactant elements (e.g., Te) are introduced.
5. The process involves integration of super-heating, atomizing, and reacting steps into one single operation. This feature, in conjunction with the readily achieved super-heat conditions, makes the process fast and effective and now makes it possible to mass produce nano-sized semiconductor particles cost-effectively.
6. The apparatus needed to carry out the invented process is simple and easy to operate. It does not require the utilization of heavy and expensive equipment. Further, the feeding of metallic wire in a twin-wire arc machine is a continuous process. Hence, the over-all product costs are very low.
FIG. 1(A) showing the schematic of an apparatus for producing quantum-sized compound semiconductor in accordance with a preferred embodiment of the presently invented method, (B) enlarged version of the top portion of (A), and (C) showing another preferred embodiment of the method wherein the atomizing fluid medium also contains a reactant element to react with the produced nanometer-sized metal fluid droplets.
FIG. 2 schematically shows the working principle of an electric arc spray-based device for generating a stream of highly super-heated fine metal liquid droplets or vapor clusters (two examples of the heating and atomizing means): (A) an open-style arc-spray nozzle and (B) a closed-style arc-spray nozzle in which the arc zone is enclosed by an air cap 76.
FIG. 3 a plasma spray nozzle as another example of the heating and atomizing means.
FIG. 1A and FIG. 1B schematically show an apparatus for producing quantum-sized compound semiconductor particles, in accordance with a preferred embodiment of the present invented method. This apparatus includes three major functional component systems: (1) a heating and atomizing means 11 to produce ultra-fine, highly super-heated metal liquid droplets or vapor clusters, (2) a means for supplying a fluid medium containing a reactant element, selected from the group consisting of P, As, S, Se, Te and combinations thereof, to impinge upon and react with the super-heated metal droplets or clusters to form compound semiconductor particles, and (3) means for cooling and/or passivating the resulting particles to obtain the desired solid compound semiconductor quantum particles.
In the heating and atomizing means, there provided heating means for melting a metallic material (normally supplied in a wire, rod, or powder form) and for super-heating the metal melt to a temperature normally at least 1000 degrees Kelvin above the melting point of the metal. Also provided is an atomizing means for breaking up the super-heated metal melt into ultra-fine liquid droplets (smaller than 40 nm in diameter, preferably smaller than 20 nm, and most preferably smaller than 10 nm). In a preferred embodiment of the present invention, as indicated in FIG. 1A and FIG. 1B, the heating and atomizing means includes a twin-wire electric arc spray nozzle, which is mainly comprised of an electrically insulating block 74, two feed wires 50, 52 and an atomizing device containing an atomizing gas passage means 78. The two metal wires 50,52 are supplied with a DC voltage (one "+" and the other "−") or a pulsed power 70 to form an arc 13 in an arc chamber 15. This arc 13, being at an ultra-high temperature (up to 6,000� C.), functions to melt the wire tips and super-heat the resulting metal melt. A stream of atomizing/carrier gas passes through the passage means 78 into the arc chamber 15 to atomize the metal melt (breaking up the melt into ultra-fine liquid droplets) and to carry the stream of metal liquid droplets downward toward the top portion of a reaction chamber 90.
The two wires 50,52 can be fed through air-tight means 5 a,5 b into the arc chamber 15, continuously or intermittently on demand, by a wire-feeding device (e.g., powered rollers 54 as indicated in FIG. 1B). The atomizing device is operated in such a fashion that it provides a stream of liquid droplets or vapor clusters that are as highly super-heated and as finely divided as possible. The speed of a stream of arc-forming gas (through 60 from 62) cannot be too high due to the fact that the gas comes in direct contact with the arc 13. Too high a gas speed in this stream could adversely affect the quality of the arc, e.g., may tend to diminish or extinct the arc. The speed of the atomizing gas coming from 78 can be much greater for more effective atomization.
The reactant gas supplier means 80 has a nozzle orifice 84 that is strategically positioned and oriented with respect to the super-heated metal droplets or clusters 82 so that a reactant gas coming from a chamber 83 can rapidly react with these super-heated droplets or clusters to form compound semiconductor particles. A selected reactant element 114 in a container 116 is heated by a heater 118 to become vaporized or sublimed into a vapor phase that is carried by a carrier gas from a source (not shown) through a pipe means 112 into the chamber 83 through an exit orifice 81. Preferably, this reactant gas supplier means is itself also an atomizing means (such as a vortex jet atomizer that has a gas accelerating chamber or channel 83 and a nozzle 84), so that the super-heated metal liquid droplets can be further broken up into quantum sizes.
The nanometer-sized compound semiconductor particles are directed to enter the top portion of a reaction chamber 90. These individual particles 82 a, remaining in a liquid or vapor state at high temperatures, could aggregate or stick together if left alone. It is therefore desirable to employ a solid powder formation facilitator means (cooling and/or passivating means) to help the particles solidify and remain separated from one another. The powder facilitator means may include blowing a cooling medium (e.g., cool inert gas) through pipe means 122 and sprayer 125 to impinge upon the particles 82 a. The cooling means may also include copper or steel tubing 92 (FIG. 1A) or channels, containing cooling water, that are jacketed around the atomizer chamber 90 to facilitate solidification of the particles 82A therein for forming solid powders. These powders, along with the residual atomizing gases and cooling gas are transferred through a conduit 97 to a powder collector/separator system.
The passivating means may comprise a passivating material 124 inside a container 126 which is heated to a vapor state. The vapor is transported by a carrier gas from 122 to enter the reaction chamber 90 and be sprayed out of the sprayer 125 to react with or coat the surface of the compound semiconductor particles 82 a. The passivating material can be selected from the group consisting of an organic monomer, a low molecular weight polymer (oligomer), a metal, a non-metallic element, or a combination thereof. The metallic material is preferably selected from Group IIB, IIIA, IVA, and VA of the Periodic Table. The non-metallic element is preferably selected from the group consisting of P, As, S, Se, Te, or a combination thereof. Another preferred class of passivating materials contains phosphide, sulfide, arsenide, selenide, and telluride that is vaporized to deposit as a thin coating on the compound semiconductor particles 82 a. The passivated semiconductor particles not only have a higher tendency to remain isolated (not to agglomerate together), but also have a higher quantum yield when used as a photoluminescent material. The latter phenomenon is presumably due to a dramatic reduction in the surface electronic energy states that would otherwise tend to result in a non-radiative electronic process.
For instance, passivation can be achieved by reaction of the surface atoms of the quantum dots with organic passivating ligands, so as to eliminate the surface energy levels. The CdSe nano crystallites can be capped with organic moieties such as tri-n-octyl phosphine (TOP) and tri-n-octyl phosphine oxide (TOPO). Passivation of quantum dots can also be achieved by using inorganic materials. Particles passivated with an inorganic coating are more robust than organically passivated dots and have greater tolerance to processing conditions necessary for their incorporation into devices. Examples of inorganically passivated quantum dot structures are CdS-capped CdSe, CdSe-capped CdS;, ZnS grown on CdS, ZnS on CdSe, CdSe on ZnS, and ZnSe on CdSe.
As schematically shown in FIG. 1A, the powder-gas mixture effluent transferred from the conduit 97 flows into the chamber of a cyclone or vortex powder classifier 94, which is provided with a reverse flow capability. With a feeder valve 95 being open, the coarse particles are collected in container 101. Finer particles along with the residual gas are fed into the chamber 98 of another cyclone which collects fine particles through a valve 105 into a container 104. The residual ultra-fine particles and gas are conveyed through a conduit 99 into a dust collector 100 which has a container 107 to collect the dusts (ultra-fine powders), allowing the clean air to exhaust out.
An alternative preferred embodiment of the present invention is a method that includes a different sequence of steps. Specifically, referring to FIG. 1C, the method begins with (a) operating a heating means to generate super-heated fluid droplets of at least a metallic element (selected from Groups IIA, IIB, IIIA, IVA, and VA of the Periodic Table) in a reaction chamber, which is followed by (b) directing a stream of a reactant fluid medium comprising at least a reactant element (e.g., P, As, S, Se, and/or Te) into this reaction chamber to concurrently atomize and react with the super-heated metal fluid droplets to form substantially nanometer-sized phosphide, arsenide, sulfide, selenide, and/or telluride compound semiconductor particles. The method ends with the step of cooling and/or passivating these compound particles to form the desired compound semiconductor quantum particles in a solid state. In this alternative method, atomization and reaction are combined into one step. The reactant element vapor originated from 114 in container 116 is conveyed by a pressurized carrier gas (also an atomizing gas) and introduced into the channel 83 of a vortex jet atomizer 83. The atomizing/reacting gas mixture that exits at the orifice 84 acts to concurrently atomize and reacts with the super-heated liquid droplets created by the arc. The resulting compound semiconductor quantum particles are then cooled and/or passivated and collected.
The twin-wire arc spray nozzle is but one of the many devices that can be used as a heating and atomizing means. Other types of thermal spray devices that can be used in the practice of the present invention include a plasma spray device, a gas combustion spray device, an induction heating spray device, a laser-assisted spray device, and combinations thereof. An electric arc spray nozzle, particularly a twin-wire arc spray nozzle, is a preferred choice, however. The twin-wire arc spray nozzle, originally developed for use in a spray coating process, can be adapted for providing a continuous stream of super-heated metal melt droplets. This low-cost process is capable of readily heating up the metal wire to a temperature as high as 6,000� C. and is further illustrated in FIG. 2A and FIG. 2B.
Schematically shown in FIG. 2A is an open-style twin-wire arc spray nozzle 11A. Two metal wires 50,52 are driven by powered rollers 54 to come in physical contact with two respective conductive jackets 72 which are supplied with "+" and "−" voltage or pulsed power through electrically conductive blocks 56 and 58, respectively. The voltage polarity may be reversed; i.e. "−" and "+" instead of "+" and "−". The voltages come from a DC or pulsed power source 70. The lower ends of the two wires approach each other at an angle of approximately 30-60�. The two ends are brought to contact each other for a very brief period of time. Such a "short circuit" contact creates an ultra-high temperature due to a high current density, leading to the formation of an arc 66. A stable arc can be maintained provided that the voltage is constantly supplied, a certain level of gas pressure is maintained, and the wires are fed at a constant or pulsating speed. A stream 64 of compressed air, introduced through a gas passage 60 from a gas source 62 (e.g., compressed air bottle, not shown), serves to break up the melt produced inside the arc zone 66 to become finely divided metal melt droplets 68, which remain highly super-heated (i.e., at a temperature much higher than the melting point of the metal, typically by at least 1,000� in Kelvin scale).
The metal melt droplets produced by the above-described open-style twin-wire arc spray nozzle tend to be high in diameter. An improved version is a closed-style arc spray nozzle 11B as schematically shown in FIG. 2B. In this spray arc nozzle, the arc zone is enclosed by an air cap 76 and additional compressed gas or air (referred to as the secondary atomizing gas) is introduced (e.g., from 78) into the arc zone to compress the arc. The increased arc zone pressure effectively increases the atomizing speed and the arc temperature, thereby promoting the more efficient atomization resulting in much finer liquid droplets. These super-heated fine liquid droplets can be optionally further atomized by a vortex jet atomizer 83 (FIG. 1A).
Other types of thermal spray devices that can be used in the present invention include a plasma arc spray nozzle. FIG. 3 shows an example of a plasma spray nozzle that involves feeding a wire 228 of metal (or metal powders) into the transferred arc 227 which rapidly fuses the metal for atomization. A large secondary flow of compressed air functions to atomize the molten metal into fine super-heated droplets. This plasma arc spray nozzle is comprised of the following major elements. An electrode 221 is mounted coaxially within an electrically insulating block 220 at one end of a cylindrical metal body 222, the opposite end of the body 222 is closed off by an end wall 212, provided with an axial bore forming a nozzle orifice 240. The electrode 221 is coaxial with the nozzle passage or bore, and within an annular chamber 225. A plasma-forming gas is introduced through a tube 223 to chamber 225, where the plasma-forming gas passes into and through the nozzle orifice 240. Concentrically surrounding the body 222 is a cup-shaped member 233, forming an annular space 241 between the cup-shaped member 233 and the cylindrical body 222. One end of the cup-shaped body 233 is closed off by end wall 233 a, while its opposite end 233 b is open. Compressed air is introduced through a tube into the annular space 241 for discharge through the open end of the cup-shaped member 233 to form a high-speed air flow 236, which functions to atomize the metal fed into the plasma arc (arc column being indicated by 227). The wire 228 is fed into the developed arc 227 by powered rollers 229 which rotate in the direction of the arrows to feed the wire. An electric potential difference is developed between the wire 228, an anode, and the electrode 221, a cathode, from a DC electric source 232 via leads 230,231 coupled respectively to the cathode 221 and the anode wire 228. The ultra-high temperature in the plasma arc (typically between 2,000� K. and as high as 32,000� K.) rapidly melts out and highly super-heat the metal, which is instantaneously atomized by the air flow 236 to become ultra-fine fluid droplets 237. These highly super-heated fluid droplets are directed to flow into a reaction chamber (not shown in FIG.3) where they are reacted with a reactant to form compound semiconductor particles. Alternatively or additionally, the atomizer-carrier gas may contain a reactant gas which reacts with atomized metal droplets or clusters to form nanometer-size compound semiconductor particles in the chamber.
At an ultra-high temperature (e.g., 1,000 to 2,000� K. above the metal-melting point or 1.5 to 3.0 times of the melting point using absolute Kelvin scale), the surface tension of the metal melt is negligibly small and the liquid stream can be readily broken up into ultra fine droplets. Table 1 shows a recommended range of processing temperatures for the metal elements involved. The processing temperatures for the reactants are given at the bottom of Table 1.
As shown in FIG. 1B, the reactant supplier means 80 may comprise a jet nozzle having on one side inlet pipe means 81 for receiving the atomizing fluid medium from a fluid source (e.g., compressed gas bottle, not shown, and a reactant vapor from 114) and on another side a discharge orifice 84 of a predetermined size and shape through which the atomizing fluid is dispensed to impinge upon the stream of super-heated metal melt droplets 82. Preferably, the nozzle discharge orifice 84 is annular in shape and coaxial with the stream of metal melt droplets 82. The orifice outlet 84 is oriented in such a fashion that the pressurized fluid (e.g., sulphur-containing gas), immediately upon discharge from the orifice, impinges upon the super-heated metal melt stream. It may be noted that, if the atomizing gas coming out of the orifice 84 contains a reactive gas such as sulphur, the highly super-heated metal droplets can quickly react with sulphur to form sulphide particles. Since the metal sulphide formation is normally a highly exothermic process, a great amount of reaction heat is released, which can in turn be used to activate, maintain, or accelerate the sulphide formation reactions of other metal droplets. Such a self-sustaining reaction rapidly converts the liquid droplets into compound semiconductor particles.
Table 2 and Table 3 show the relative free energy of formation (ΔG) data for various compound semiconductor materials, calculated based on the heat of formation (ΔHf) and entropy of formation (ΔS) data at 298� K. (the heat and entropy data are available from "Smithells Metals Reference book", 6th Ed., edited by E. A. Brandes, Butterworths, 1983). The data on the free energy of formation obtained indicate that the amounts of energy released during the formation of a sulphide, selenide, telluride, and phosphide phase are respectable, although not as high as in a metal oxidation reaction. These amounts of heats were found to be sufficient to maintain a self-sustaining reaction.
As a preferred embodiment, the jet nozzle may be a vortex-loop-slot jet nozzle for a more 40 efficient atomization action. A pressurized gas may be introduced from a compressed air source through one or more inlet pipes (e.g., 81) into a vortex chamber 83 in which the gas molecules swirl around several circles before finally entering the annular slit leading to the orifice 84. This configuration allows the pressurized fluid (the atomizing medium) to effectively transfer the kinetic energy of the high speed fluid molecules to the stream of liquid metal droplets 82. A variety of atomizing nozzle configurations are available in the prior art. Examples include those disclosed in U.S. Pat. No. 5,656,061 (Aug. 12, 1997 to Miller, et al.), U.S. Pat. No. 5,125,57 (Jun. 30, 1992 to Anderson, et al.), and U.S. Pat. No. 3,988,084 (Oct. 26, 1976 to Esposito, et al.).
A cyclone, 94 or 98, is normally cooled (e.g., externally water chilled) to cool the powder product. As the product fluids travel through cyclones 98, the powder drops into receiver 104 with the valve 105 being open, while gaseous effluent leaves cyclone 98 through conduit 99 into a solid separation chamber (e.g., a dust collector 100 or a wet scrubber). The wet scrubber can be a caustic water scrubber, containing packing of balls, saddles, etc. for greater contact. The scrubber separates the fine solid particles from the gas stream and possibly neutralizes acidic species therein before the gas is discharged to the atmosphere or to a flue. Any additional filtering device such as a bag filter, electrostatic precipitator or other equivalent means for separating suspended solids from a gas may be used. While only two cyclones and one solid separator are shown, more than two cyclones can be used. Alternatively, other types of powder collector and/or separator devices may be used. Solid powder collector and solid-gas separator systems are widely available in industry. Some examples are given in U.S. Pat. No. 4,282,195 (Aug. 4, 1981 to Hoekje), U.S. Pat. No. 4,490,162 (Dec. 25, 1984 to Davis), and U.S. Pat. No. 6,042,628 (Mar. 28, 2000 to Nishikiori, et al.).
Patent Citations
Non-Patent Citations
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Originally written on Fox Sports | Last updated 7/14/12
Lance Ten Broeck expected to make it to the weekend at the U.S. Senior Open. The full-time caddie and part-time player, though, didn't dream of being the second-round leader. Ten Broeck shot a 68 on Friday, putting him at 6-under 134 and one shot ahead of first-round leader Tom Kite. The 56-year-old Ten Broeck, who caddies for Tim Herron, finished tied for 71st at his only other Champions Tour event this year. He estimates he plays about 25 rounds a year. ''I guess that means I'm well rested,'' he joked. Ten Broeck got a chance to sleep in before starting the third round because he earned a spot in the final pairing. ''I knew I was playing pretty good in spite of having not really played much,'' he said. ''But I figured I should be able to make the cut, but I never figured that I'd be in the last group on Saturday.'' While many fans were likely stunned to see Ten Broeck atop the leaderboard, Kite insisted he wasn't shocked. Kite has known Ten Broeck since he was a standout g...
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subset: commoncrawl


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News Releases
Linda O'Dwyer
Presence Health
Single-Site Cholecystectomy Performed for First Time at Presence Saint Francis Hospital
Evanston, Illinois (May 2, 2014) – A single-site cholecystectomy was performed for the first time at Presence Saint Francis Hospital this spring by Michael Prendergast, M.D.,(pictured at right) using new technology now available at the hospital. Dr. Prendergast removed the patient's gallbladder through a small incision in the belly button, making the surgical site virtually scarless.
Laparoscopic surgery, the more common surgery for gallbladder removal, requires three small incisions around the right ribcage and can leave obvious scarring. "The patient preferred the single site procedure because she's a young woman who didn't want a visible scar on her abdomen," said Dr. Prendergast. "Single-site cholecystectomy (the medical term for gall bladder removal) offers patients rapid recovery time, significantly less pain, less blood loss and quicker returns to normal daily activities. The lack of a visible scar is ideal and of interest to almost any potential patient."
The technology, known as the daVinci Si, at Presence Saint Francis Hospital offers surgeons an alternative to traditional laparoscopic cholecystectomy for the approximately one million Americans who have their gallbladder removed each year as treatment for gallstones and other medical conditions. The surgical system provides the physician with high-definition 3D vision inside the patient, and its extended surgical arms can reach areas that normally would not be easily accessible. Several different tools can be attached to the surgical arm to perform precise functions in the surgical suite.
"We are pleased to offer advanced technologies such as the da Vinci Si, and the latest surgical options to our community because of the significant value it offers our surgical staff and the patients we serve," said Roberta Luskin-Hawk, M.D., president and CEO of Presence Saint Francis Hospital in Evanston and Presence Saint Joseph Hospital in Chicago. "These technological advancements provide our surgeons with unparalleled precision, dexterity and control that enable a minimally invasive approach for many complex surgical procedures."
About Presence Saint Francis Hospital
Presence Saint Francis Hospital is a nationally recognized, full-service 271-bed hospital with a Level I Trauma Center and is listed as one of Chicago's top hospitals by U.S. News & World Report. As home to the first Chest Pain Center on Chicago's north shore and a Primary Stroke Center certified by the Joint Commission, Presence Saint Francis Hospital has a rich history of providing top quality care and leading edge technologies in collaboration with its 430-physician medical staff. Presence Saint Francis Hospital has been designated a Magnet Hospital by the American Nurses Credentialing Center, placing it in the top seven percent of U.S. hospitals for nursing excellence. More information is available at http://www.presencehealth.org/stfrancis.
About Presence Health
Presence Health is the largest Catholic health system based in Illinois, created in November, 2011 through the merger of Provena Health and Resurrection Health Care. With more than 150 sites of care, including 12 hospitals, Presence Health has 22,000 employees and 4,000 medical professionals. More information is available at http://www.presencehealth.org.


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Bourque on facing Capitals: "There'll be a few guys probably coming after me"
Jan 17, 2012, 3:10 PM EDT
The trade that moved Rene Bourque from Calgary to Montreal was something of a double-edged sword. While it presented Bourque an opportunity for a fresh start with a new team, it also meant he'd have to face the Washington Capitals again.
Bourque's been public enemy No. 1 in Washington since elbowing and concussing Caps leading scorer Nicklas Backstrom on Jan. 3.
"I obviously don't feel good about what I did and I apologized for it, but I'm sure they'll be a few guys probably coming after me tomorrow," Bourque told Canadiens.com. "It's part of the game and I just need to be prepared for it. I know guys will be looking to make sure they finish their checks against me."
Bourque — then a member of the Flames — received a five-game suspension for the elbow. Backstrom's been out since the hit (likely to remain out until after the All-Star Game) and only now do the Caps have a chance for revenge.
See, Washington wasn't scheduled to meet Calgary again this year, which meant no more meetings with Bourque. That's a stark contrast to Bourque's new team — Montreal and Washington play four more times this season, beginning with tomorrow night's affair at the Bell Center.
Montreal assistant captain Josh Gorges said that even though Bourque wasn't with the Canadiens at the time of the incident, the team will still have his back should something occur.
"It's a little different because we weren't there originally," Gorges said. "Maybe someone will come after him and challenge him or something like that but he's on our team and he wears the same jersey as us so we're going to be there to back him up if he needs it."
- xxshookonexx - Jan 17, 2012 at 3:22 PM
Two soft teams going after each other. The jersey grasping and face washing will be off the charts. There may even be some PIMs that come from it.
- 1943mrmojorisin1971 - Jan 17, 2012 at 6:00 PM
- 1943mrmojorisin1971 - Jan 17, 2012 at 6:00 PM
In response to all those unwarranted thumbs down.
- jpelle82 - Jan 17, 2012 at 8:43 PM
that video will never get old!
- jpelle82 - Jan 17, 2012 at 4:52 PM
he doesnt have anything to worry about…nobody on the caps to worry about at least. they didnt do anything in the first place when he delivered the hit so why would they do anything now? who would anyway? matt hendricks? bahahaha
- bcjim - Jan 17, 2012 at 6:02 PM
The Caps can throw their weight around when they want to.
Erskine could kill him but I think he is recovering from something and hasn't been mixing it up lately.
Or they could call up good ol DJ King…talk about exiled.
Hendricks is a decent fighter.
Chimera is a surly mofo.
If all else fails Dale can just take care of business like he did in the old days.
Top Posts
- Brandon Saad brings championship experience to Blue Jackets 12
- Sharks sign Joel Ward to three-year deal 16
- Sabres lock up O'Reilly through 2022-23 56
- Locked in: Columbus signs Saad to six-year, $36M deal 25
- Oilers sign McDavid to entry-level contract 24
- 'Hawks would like to re-sign Oduya, but still working through 'financial hurdles' 17
- Trade: Caps acquire Oshie from Blues for Brouwer, Copley and draft pick 73
- Voynov takes plea, gets 90 days in jail plus probation 60
- Curtains on Broadway: Martin St. Louis calls it a career 36
- Discuss: Where's the best fit for Alex Semin? 23
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- Blockbuster: Kessel traded to the Penguins (131)
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- Trade: Jackets land Saad; Anisimov and Dano headed to Chicago (93)
- Bypassing a buyout? Kings terminate Richards' contract for 'material breach' (90)
- Trade: Caps acquire Oshie from Blues for Brouwer, Copley and draft pick (73)
- M. Richards (2586)
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- B. Saad (1865)
- S. Voynov (1826)
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- D. Hamilton (1672)
- B. Richards (1639)
- S. Gagner (1615)


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Results 1 to 4 of 4
Thread: Opinion please...
July 1st, 2003 #1Registered User
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- Jun 2003
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Opinion please...
hi guys,
i'm new here. i'm just a beginner to concept art. Until this time I just used to copy other drawings....
I just drew one of my concepts. I drew the Hindu god of snakes (known as Vaasuki). It's my 1st complete work. I also painted it in Photoshop. But I personally think this work didn't achieve the result I expected.
I want views from all of you....regarding my mistakes or whatever.
Hope you guys will help me.
The outline (inked):
The coloured one:
Hide this ad by registering as a memberJuly 2nd, 2003 #2
first mistake : you posted that in the wrong forum. Post it in "Work In Progress".:evilbat:
July 2nd, 2003 #3Registered User
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Hi there, welcome to ConceptArt, Radon
I would recommend U to study a bit more drawing, especially the human body. U can do this by go to nude figure study classes or buy a book in the subject. The link www.fineart.sk can also be helpful, aswell as the refence section here in CA.
U can also take part in the daily sketchgroup here at CA (DSG for short - U need IRC - asylumnet.org #sketch).
Try maybe to draw (loose sketches) about one hour a day - they say that gives improvement in a year.
If, judging by your style, U want to draw not-so-average people, maybe the marvel superhero drawing guides can be helpful too.
Once in a while - do a bigger thing, a project, drawing and color it in a few weeks.
And dont be afraid of copying - we all need crutches in the beginning.
U have just embarked on a jorney that U can travel all your life - nothing brings me joy and satisfaction like drawing.
Good luck :chug:
PS - repost this on Work in Progress - DS
July 16th, 2003 #4Registered User
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Draw, draw, draw.
Never give up and never surrender.
"Keep having meetings, of minds and of heart. Keep drawing, keep throwing drawings away.
Make it good, make it better, make it so good that "they" have to want it" - Walt Disney.
My first 10 years, full time, with only pencils, paid off. Now I can draw in my sleep. Some people are born with that raw talent and others, like me, work hard at it everyday, pushing oneself, a learner for life.
"To achive the impossible you have to attempt the absurd."


text:
Stefano Zacchiroli is Debian's New Project Leader
Debian developers have elected Italian Stefano Zacchiroli, alias Zack, as their new project leader.
Zacchiroli won the election, which was run using the Condorcet ranked voting method, with 14.11 points over his rivals Margarita Manterola, Wouter Verhelst and Charles Plessy. Second place went to Verhelst (9.62 points), third place to Manterola (7.62) and fourth place to Plessy (1.19).
Zacchiroli replaces Steve McIntyre, who had the active DPL role since 2008 and decided not tor run for a third term. Details on the DPL election are on the Debian homepage.
Error in articleThere's a mistake in the article -- Margarita Manterola beat Wouter Verhelst.
See the graph on http://www.debian.org/vote/2010/vote_001 (or read the long explanation there of what the numbers mean).
Issue 177/2015
Buy this issue as a PDF
NoScript Flaw
Mozilla's script blocker add-on could be putting malware sites on the whitelist.
RIP SSLv3
The Internet community officially banishes the notoriously unsafe Secure Sockets Layer protocol.
Mate 1.1 Arrives
Popular desktop environment continues the Gnome 2 legacy – with new support for the Gnome 3 toolkit.
US Government Requires HTTPS
The Obama White House has issued a memorandum telling all US government agencies they must use HTTPS for all websites and web communication.
Mozilla Signs Firefox Add-Ons
New program will dial up security for the Firefox browser.
Fedora 22 Arrives
Red Hat's community distro embraces the cloud.
Code.org and College Board Team Reach Out for Talented High School Coders
New partnership will bring more and better CS training to US schools
A Peek Inside TeslaCrypt Ransomware
Criminals offer online help over Tor network
Mumblehard Still Spams
Sophisticated malware is still present on Joomla and WordPress sites around the world.
Launchpad Gets Git
Future versions of Ubuntu's code service will support the popular Git version control system used with Linux and other open source projects.


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My wife and I were recently visiting my wife's uncle and in the course of casual conversation he and I started to talk about his myriad RC boats, airplanes, cars etc. I was so interested in them (and he is such a generous guy) that he gave me his Traxxas Slayer which I am just starting to learn more about owning and operating.
One thing he didn't have an extra of was a charger (for the EZ starter battery pack) so he told me that I would need to buy one from my local hobby shop when I got home. I purchased an EZ-Peak quick charger, and the guy at the hobby shop also encouraged me to get a 5 cell battery pack for the receiver. He told me that the EZ-Peak would also charge the receiver battery pack, but now that I have gotten home I see it says in the instructions that I should not charge receiver packs or packs with fewer than 6 cells. I already charged the receiver pack. Do you think it is ok? Can this charger be used to charge my 5 cell receiver pack in the future, or is this a bad idea?
Thanks for your input.


text:
The VersiCam video detection system (VIDS), for monitoring traffic conditions at smaller intersections, consists of a high-resolution traffic camera with remote zoom and focus functions, and a high-sensitivity CCD imager to help ensure accuracy of vehicle detection in any lighting conditions. Interface functions are performed through the interface communication controller (ICC), which is housed securely in the roadside cabinet.
Iteris Inc.www.iteris.com
Booth 403
As California suffers into its fourth year of a historic drought, some see new water...
Traffic Control
Transportation Safety
Public Works Staff
APWA Convention Exhibitors
Services allow users to easily create customized mobile services for both public works...
GIS tool uses "Big Data" to resolve traffic-design challenges.
Please read our Content Guidelines before posting.
Copyright ©
2015 Hanley Wood Media, Inc. All rights reserved.


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Vol. 28-2 is now here!
Click Here to Get Your Copy!
The Lois Prize deadline has been extended to June 30, 2015
Click Here to Submit!
New Release
Summer Journal Vol. 27:2
Click to purchase!
Mrs. Vargas and the Dead Naturalist
by Kathleen Alcalá
now available as an eBook
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How to backup Oracle Databases running on Solaris Cluster
We have setup backups jobs for backing up Oracle Databases running into a single server. But now We have to run backups from a cluster where two servers are running databases and if a server fails the databases running on that server are going to move to the second server into the cluster. So, how can we setup the scripts or what do we need to do to continuos backing up those tatabases no matter the server that is running those tatabases.
Any Idea can help us.
Best regards
Comments 1 Comment • Jump to latest comment
You use the service name instead of the physical host names.
You may find this link usefull:
How to Enable NetBackup to Run on a Cluster
Netbackup 7.5 Oracle Admin guide - About virtual names and NetBackup for Oracle
Assumption is the mother of all mess ups.
If this post answered your'e qustion - Please mark as a soloution.


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Body Transformation Retreat
This Retreat is All inclusive! Room, every meal, snack, juice, smoothies, and two spa treatments per day!
Read a few testimony's from the August 2014 retreat HERE
Go to the Mii amo website for FULL retreat itinerary.
Listen to my podcast by Mindful Adventures about the Body Transformation Retreat! Click HERE to LISTEN!
Read what Forbes.com had to say about the BTR HERE
Upcoming Retreat!
2015 Body Transformation Retreat Schedule
August 24-28, 2014 "The MonSPOONS' (Guy, Louisa, Heather, Susanna, Kelly, Kelley, Chris, Trisha, Jenn, Karen)
About Us
Danielle Fryer, RD, CSSD, CFT
Performance Nutrition and Strength Training. Vedic Thai Bodywork Massage. Registered Dietitian/Nutritionist & Board Certified Sports Specialist in Dietetics and Certified International Fitness Trainer.


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A few quick changes can make your visitors feel like they're living the luxe life.
Kitchen and Bath Counters That Inspire
Interior designer Steven Gambrel imbued a guest room at his house in Sag Harbor, New York, with a pale-blue shade. Made of Belgian linen, the curtains are striped to match.
Rayman Boozer, an interior designer and owner of the Manhattan shop Apartment 48, painted the living room of his apartment with Benjamin Moore's Old Pickup Blue.
A London Townhouse Revitalized


text:
(plural graduators)
- One who determines or indicates graduation.
- a graduator of instruments
- An instrument for dividing any line, straight or curved, into smaller regular intervals.
- An apparatus for diffusing a solution, such as brine or vinegar, over a large surface, for exposure to the air.
graduate + -or
Variant of graduate
- a person who has completed a course of study at a school or college and has received a degree or diploma
- a flask, tube, or other container marked with a progressive series of degrees (lines or numbers or both) for measuring liquids or solids
Origin of graduate; from Medieval Latin graduatus, past participle of graduare, to graduate ; from Classical Latin gradus: see grade
transitive verbgraduated, graduating
- to give a degree or diploma to in recognition of the completion of a course of study at a school or college
- Informal to become a graduate of: to graduate college
- to mark (a flask, tube, gauge, etc.) with degrees for measuring
- to arrange or classify into grades according to amount, size, etc.
- to arrange in grades or stages: graduated income tax
intransitive verb
- to become a graduate of a school or college
- to change, esp. advance, by degrees
- having been graduated from a school, college, etc.: a graduate engineer
- ☆ designating, of, for, or participating in instruction or research in various fields leading to degrees above the bachelor's: graduate courses, graduate students
Related Forms:
- graduator


text:
Win 50,000 Club Carlson Gold Points!
Put on your lucky underpants and start dreaming up your next vacation, because it's giveaway time again on Travel Freak!
The Carlson Rezidor Hotel Group is one of the world's largest hotel companies with 1,319 hotels in operation and under development covering 81 countries and territories. You'll probably recognize some of their global brands: Radisson Blu, Radisson, Park Plaza, Park Inn by Radisson, and Country Inns & Suites By Carlson.
We could talk more about their individual properties, but we'll cut to the chase: to help spread the word about their Club Carlson Triple Points promotion the group is giving away 50,000 Club Carlson Gold Points to one of our lucky readers!
Since you're probably asking yourself in your head – no, you do not need a Club Carlson membership to take part in the giveaway. However, if you win you'll need to sign up in order to claim your points. Don't worry, though. It's free, easy, and worth it when considering all the awesome things you can do with your winnings.
Nights at Carlson Rezidor properties range from 9,000 to 50,000 points per night depending on the hotel's location and amenities, so you could use your award points for up to 5 nights depending on where you want to stay. Or, if a hotel stay isn't in your future, you can also redeem your points for airline miles, PayPal cash or a charitable donation. We got a handful of Gold Points ourselves for helping Carlson Rezidor with the promotion, and we have absolutely no idea what to do with them yet! We'd say we're giving them all to charity, but you know that's not true.
There are multiple ways to enter your name into the drawing between now and midnight EST on March 7, so come back every day to increase your chances of taking home this amazing prize! The prize will be processed within 4 to 6 weeks after we announce the winner, which is the perfect amount of time to start browsing Club Carlson properties and planning how to spend your 50,000 gold travel nuggets.
Remember, if you're already a Club Carlson member or have just signed up to take advantage of this giveaway, be sure to check out the Triple Points promotion which allows members to earn three times the amount of points on hotel stays completed before March 15. But, we repeat, you do not have to be a current Club Carlson member to enter this giveaway.
Good luck!
This is such an awesome prize! I am using Club Carlson points to get a great redemption for my upcoming trip to Russia.
What a great contest prize! Thanks for the chance to enter!
Facebook: https://www.facebook.com/bari.teakaadee
Twitter: @eldialacrimosa
Pinterest: pinterest.com/femmegauche
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E-mail: falses1gns at gmail dot com
Awesome giveaway! I can use a vacation!
Pinterest: kfloveinme
Sweet prize! Hotel points always come in handy.
[…] is giving away a week-long trip to the Mayan Riviera! That reminds us, have you entered our amazing giveaway yet? Do both and be the ultimate bargain […]
Facebook–Susan Stripling Edwards
Would love the 50K CC points! Thanks!
I would love to win 50,000 points to feed my travel addiction. While all of the other hotel chains are dissing their clientele – devaluing points and running lousy promos, Club Carlson is going above and beyond the others in trying to woo and win our affections. I say – they deserve our support!
I don't need these points for anything fancy…would be happy with a free stay at the Country Inn and Suites in Salt Lake City.
For the euro zone!
Would use on a nice trip to Europe.


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environmental management systems Companies in California
Bays Environmental Remediation Management
based in Ladera Ranch, CALIFORNIA (USA)
Environmental Remediation Project Management, Injection and extraction methods, Remediation System Optimization, Pilot testing, Soil Vapor and Ttwo-phase Extraction, Remedial option selection, Site Closure Package Preparation, Remediation Project Funding Solution, Contaminated Property Valuation and Marketing Solutions.
CAPE Environmental Management, Inc.
based in Norcross, GEORGIA (US) (USA)
CAPE has grown from a small engineering firm to a vibrant, award winning organization with a history of sustained growth. Our expertise in Construction, Environmental Remediation, and Fuel Systems Solutions has resulted in numerous governmental and private contracts worth several billion dollars. But in the end it's our people that make CAPE an outstanding organization.
Wright Environmental Management Inc
based in Richmond Hill, ONTARIO (CANADA)
Wright Environmental Management Inc. was founded in 1992, and with more than 55 installations in United States, Canada, and the United Kingdom, Wright is the world`s largest supplier of completely-enclosed, continuous composting systems. Wright provides composting solutions to customers with municipal solid wastes (also called mixed solid waste or MSW), biosolids, food ...
Environmental Management Consultants, Inc.
based in Derby, CONNECTICUT (USA)
Environmental Management Consultants, Inc. (EMC) is a full service environmental management, remediation, industrial health and safety firm providing services to industry within the continental United States, Canada, Puerto Rico, Mexico and certain countries in Latin America and Europe. Utilizing this approach, we have the ability not only to provide expertise in a ...
Environmental Compliance Systems, Inc.
based in Lake Mills, WISCONSIN (USA)
Environmental Compliance Systems Inc. specializes in risk management and performance improvement. ECSI provides auditing, consulting, and training services which improve overall business function while increasing profit margins.
ECOSAFE - Envrionmental Management System
based in Ocala, FLORIDA (USA)
Global Petroleum Environmental Technologies, LLC (GPET) have developed a patent-pending in-situ/ex-situ chemical treatment technology named ECOSAFE, an environmentally safe solution that when used with our ECOSAFE Environmental Management System (EEMS), degrades all hazardous and non-hazadous organics on any contaminated matrix, even pure organic phase. This solution and ...
Trace Environmental Systems, Inc.
based in Sparta, NEW JERSEY (USA)
Trace Environmental Systems, Inc. distinguishes itself by providing monitoring solutions in addition to a full range of support services. Trace Environmental is a supplier of Continuous Emissions Monitoring Systems (CEMS), Data Acquisition and Reporting Software (DAS 2000), and Environmental Data Base Management Systems. Trace Environmental provides monitoring systems, ...
Environmental & Management Services Limited (EMS)
based in West Yorkshire, UNITED KINGDOM
Environmental & Management Services Limited have a unique integrated approach to all aspects of our consultancy. Due to our practical experience within a diverse range of industries we minimise all aspects of waste by optimising our client`s process and management systems before tackling problems such as costs of waste disposal or design of abatement systems. This ...
Blue Mountain Environmental Management Corporation
based in Valencia, PENNSYLVANIA (USA)
Blue Mountain is one of the leading Source Testing companies in the Northeast. Our senior staff has a combined experience level of over 80 years. Blue Mountain is known for its high quality and superior performance, as demonstrated in diagnostic and compliance emissions sampling using EPA Reference Methods, Relative Accuracy Testing (RATA) of Continuous Emissions ...
Network Environmental Systems, inc
based in Folsom, CALIFORNIA (USA)
Nationally recognized leader in health, safety and environmental consulting and training. We provide industrial hygiene consulting, covering indoor air quality, mold, water damage and exposure to hazardous materials. We deliver environmental compliance expertise on issues including water quality, air and waste management. NES offers training on a broad range of ...


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Oak Park resident stepping down from jobs at Pepperdine
Jerry Rushford, an Oak Park resident, is stepping down as director of church relations and director of Bible Lectures at Pepperdine University in Malibu.
He will remain director of the Churches of Christ Heritage Center at Pepperdine.
Mike Cope, a minister and author, will take over as director of Bible Lectures in May 2012. Rick Gibson, vice president for public affairs and chief marketing officer, will add church relations to his role Nov. 1.
Subscribe to the Ventura County Star
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Need Help? Call us at 1-877-710-6182.
Monday-Friday: 6am-3pm / Saturday: 6:30am-10:30am / Sunday: 7am-11am


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Nice to meet you on Audiko.net! Just download a free Tata Young ringtones for your iPhone or mobile. Elect your favorite piece from your favorite music - Crush On You, I Believe, My Bloody Valentine (Thai Version), or any other track. Then download the prepared Tata Young ringtones to your mobile, and enjoy Pop music by Tata Young every time your phone rings. If you are mad about Pop or maybe Thai and Thai Pop music, then you will probably like Four Mod, Da Endorphine, or BoA as well. For all who want a free Tata Young ringtone, we also recommend listening to Asian, Alternative, and T-Pop. You may obtain your ringtone both in the MP3 and m4a formats, played by both mobile phones and iPhones. Just select a track, and choose free Tata Young ringtones download option.
Download Tata Young Ringtones
Top free ringtones
|My Bloody Valentine
|Dhoom Dhoom
|I Think of You
|Sexy, Naughty, Bitchy
|Burning Out
|I Believe
|Call Him Mine
|Crush On You
|Uh Oh
Tata Young
Tata Young
Tata Young
Tata Young
Tata Young
Tata Young


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AC cheat
Remove enough armour so your AC is at least +11. It should suddenly become 245.
Contributed By: Bodobodot.
Know Something We Don't?
You can submit new cheat codes for this game using our Cheat Submission Form.
Have We Been Fooled?
If you see a non-working or fake code in the list above, let us know by using our Problem Submission Form.


text:
Subaru reveals what's new on 2015 WRX STI at NAIAS
It gets inspiration from its racing heritage. The highly anticipated 2015 Subaru WRX STI high-performance sedan has made its global debut at NAIAS in Detroit, Michigan.
It gets inspiration from its racing heritage. The highly anticipated 2015 Subaru WRX STI high-performance sedan has made its global debut at NAIAS in Detroit, Michigan.
The all-new S-Class launch has already been very successful around the globe, but the unveiling of the new 2015 Mercedes-Benz S600 takes the S to another level.
The Mercedes-Benz S-Class Coupe is giving attendees at the Consumer Electronics Show this week a preview of just how smart future cars will be.
Subaru and Subaru Tecnica International (STI) announced they will be unveiling a number of new performance sports tourers and one will be getting the STI treatment.
The inaugural season for Stadium Super Trucks this year was a huge success and the SST series will be returning in 2014 with a new lineup of cities beginning on March 7 and running through November
Subaru has unveiled the new Cross Sport Design Concept. Could it really be a forerunner of a future BRZ Shooting Brake?
Toyota displayed a drop top concept version of the GT86 at the Tokyo Auto Show 2013, but Subaru could ax the project.
The Saleen SA-30 Mustang is the latest in a long history of high performance Ford pony cars tuned and customized by Steve Saleen's company and this new model is currently on display at the 2013 LA
The highly-anticipated 2015 WRX has arrived this week in LA and it made it's global debut with new upgrades not seen before in the performance model.
Four of Affalterbach's finest creations made their world debuts at the LA Auto Show this week. It was an exciting week at the Los Angeles Auto Show 2013 for Mercedes-AMG.
Can Subaru really be successful by replacing the next-gen WRX performance car in Europe with a wagon?
The 100th anniversary package is available on the Charger and Challenger in both SXT Plus and R/T Plus which means that buyers can get this great looking appearance package with either the 3.6L Pen
While General Motors, Ford Motor Company and the Chrysler Group comfortably dominate the full sized truck segment, their smaller models including the Chevy Colorado, the Ford Ranger and the Dodge D
It didn't take the boys at Affalterback long to get their hands on the new SUV GLA-Class.
The 2014 SRT Viper Anodized Carbon Special Edition begins on the outside with the stunning metallic matte black paint that will likely have a jazzy name but right now, the company hasn't announced
The all-new-generation 2015 Subaru WRX is about to be unveiled today, but how will current WRX fans accept the changes?


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Search the Collection
Jennifer Saunders (1958-), Actor and comedian
Sitter in 9 portraits
Worked together with Dawn French in clubs before breaking into television as part of the Comic Strip team. Their own television series, French and Saunders, was launched in 1987. Her individual career includes Absolutely Fabulous.
Joanna Lumley; Jennifer Saunders as Edina and Patsy in 'Absolutely Fabulous'
by Trevor Leighton
NPG x125837
by Trevor Leighton
NPG x125837


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Let 12 year old Ramotili tell you about his country and show you how he grows corn. An interactive map accompanies a wealth of images and activities covering the KS2 Geography and Science curricula.
Get the statistics on Nepal, the recent earthquake and ActionAid's ongoing response.
Why do people go hungry? How does hunger affect people's lives? Stats, maps, case studies and activities to help your pupils investigate.
Journey to Rio de Janeiro and Mare favela to help return a lost suitcase with our hands-on workshop.
Colourful lesson starters including map, key country information, and statistics for the big issues the country faces.
Lesson plans, assemblies, case studies, videos and more: our wide-ranging resources help you introduce global issues at all key stages.
Use the fields below to select a resource
Photo credits: Prashanth Vishwanathan/ActionAid


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Kyle Lowry suggests Nene holds back John Wall
Apr 1, 2013, 7:04 PM EDT
John Wall had 18 points and 10 assists to help the Wizards beat the Raptors last night, even though Nene missed the game due to injury. Or if you ask Toronto point guard Kyle Lowry, maybe that was because Nene missed the game.
"The floor is a little more spaced for him," Lowry said of Wall. "Having two bigs, Nene and Emeka, definitely clogged the paint where it closes up his driving lanes. Unfortunately, with Nene being out, it gives John the opportunity to get into the paint a little bit more and use his speed."
Though Lowry might have been making an excuse after Wall outplayed him head-to-head, there is some truth to his statement. Wall's points per play, via nba wowy!, decreases when he plays with Okafor and Nene.
- With only Okafor: .99
- With only Nene: .92
- With Nene and Okafor: .90
Wall is obviously central to the Wizards' future. Okafor is under contract for more than $14 million next season, and Nene has three years and $39 million remaining on his deal. So, for now, this might be a problem without a solution for the Wizards.
- llfreedman - Apr 1, 2013 at 9:38 PM
hmmm I don't know what to make of these stats. For one thing the numbers all seem pretty similar….Second, wouldn't his points per play naturally go down when another decent scorer is in the game because they take his shots away? There's gotta be some kind of efficiency usage stat that would prove Lowry's statement better.
- jaerba - Apr 2, 2013 at 12:01 AM
Eh, there might not be. The problem with Adjusted +/- is you need such a huge sample size to have any kind of reasonable confidence with it, and that doesn't exist for Wall and Nene.
You're right that his points per play could go down with more scoring options on the court, but that doesn't necessarily mean his scoring suffers. For instance, it's also possible (this is just a hypothetical) that the pace increases with Nene, so while his points per play decreases, his points per time may increase. It'd be like in business, lowering profit per unit for the sake of increasing revenue.
At this point, you'd really need a qualitative look to figure it out, with SportsVUE cameras or just good old fashioned game tape. I'm sure Lowry has a good idea of what's going on from tape.
- tigershark49 - Apr 1, 2013 at 11:35 PM
Amnesty time!!
- conjecture101 - Apr 2, 2013 at 4:19 PM
Duncan/Splitter — Parker
Randolph/Gasol — Conley
Boozer/Noah — Rose
Griffin/Jordan — Paul
Faried/Mcgee — Lawson
Ibaka/Perkins — Westbrook
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Stock Photo:
Woman and kids preparing the vegetables for a meal - washing them
- Image ID: 138711662
- Copyright: Ilike
- Release Information: Signed model release filed with Shutterstock, Inc
High quality images curated from over 150 countries.
Over 50 million photos, vectors, illustrations, and more.
Simple and flat pricing by image or by month.
Over 230,000 images downloaded every day.


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Counting in the Garden
by Kim Parker
In this gorgeous counting book, readers can count from one to ten while they search among the colorful flowers for various creatures hidden among lush garden scenes. Full color.
- Ages
- 6, 7, 5
- Interest Level
- Grades PreK - K
- Publisher
- Scholastic Inc.
- Book Type
- Counting and Number Book
- Number of Pages
- 32
About the Author
Kim Parker Read about internationally renowned textile designer and artist Kim Parker, whose first illustrated children's book, Counting in the Garden , recieved reviewers' raves.
The Reading Toolkit
Sponsor Spotlight


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Grid List
Buffalo Head Nickel BeltITEM: 9102 Buffalo head nickel design with detachable metal inlaid buckle; arrow braiding; reinforced eyelets. Imported. Leather clean.Learn More
Regular Price: $80.00
Special Price $40.00
Chief of security in soft calfskinITEM: 9611 Nothing can fall out of your wallet when it zips fully closed. Inside you'll find two convenient compartments for cash, plus areas for credit cards and coins. Fully lined. Imported.Learn More
Regular Price: $40.00
Special Price $20.00
Classic Godfather FedoraITEM: 9235 Debonair. Suave. Refined. Nothing quite says it like a classic fedora. This pure wool beauty is brimming with style, down to its feather and hat pin. Classic 2 5⁄8" brim is flattering on any shape face. Satin lining. Imported. Dry clean.Learn More
Regular Price: $120.00
Special Price $60.00
Classic Wool BeretITEM: 9251 Our 100% wool designer beret for men and women is designed to be more substantial than an ordinary beret, with satin lining to ensure it keeps its shape. Classic French styling by Hispano Basque. Imported. Dry clean.Learn More
Regular Price: $60.00
Special Price $30.00
Cowhide Biker CapITEM: 9069 Our biker cap is crafted of supple cowhide plonge for a great patina with wear. Soft and crushable. Adjustable leather back strap with antiqued brass buckle. Looks cool on women, too. One size fits most. Made in the USA. Leather clean.Learn More
Regular Price: $80.00
Special Price $40.00
Croco embossed leather capITEM: 9243 This driving cap defines cool with its croco-embossed texture. A great look, with sewn-down visor. Made in the USA. Leather clean.Learn More
Regular Price: $110.00
Special Price $55.00
Croco textured walletITEM: 9101 Premium quality and handsome style define this croco embossed flipfold leather wallet. Featuring multiple slots for credit cards and pictures, plus a window for your ID. 41⁄2"w x 31⁄2"h. Imported. Leather clean.Learn More
Regular Price: $60.00
Special Price $30.00
Genuine Fox Fur HeadbandITEM: 9828 Our glamourous fox fur head wrap is luxuriously lined in velvet with an adjustable Velcro® closure for a comfortable fit. One size fits most. Imported. Fur clean. By Damselle.®Learn More
Regular Price: $235.00
Special Price $117.50
Genuine Snakeskin Slip-ons by Giorgio BrutiniITEM: 9355 An elegant classic with a little extra style. A great look for both casual or dressy attire—with jeans or suits. Genuine leather upper and lining. Whole and half sizes, medium width. Imported.Learn More
Regular Price: $180.00
Special Price $90.00
Herringbone Pork Pie HatITEM: 9269 Raise your profile with this American original, recognized by its trademark flat top and smaller 11⁄2" turn-up brim. Choose from a bolder plaid, or the classic herringbone, each in pure wool with 1 1⁄2" wide ribbon and feather detail. Fully lined. Made in the USA.Learn More
Regular Price: $118.75
Special Price $23.75


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Upcoming programs at the K&W
March 19th - Hal Weatherman
Beginning in 2016
NC will require voters to show a photo ID when they present to
vote in person. Photo ID is any one of the following that
contains a photograph of the registered voter, have a printed
expiration date and be unexpired.
(1) A NC drivers license
(2) A special ID card for non-operators
(3) A US passport
(4) A US military ID Card OR
(5) A Veteran's ID Card by the US Dept of Veterans Affairs
(printed expiration or issuance dates not required)
(6) A tribal enrollment card issued by a federally recognized tribe. OR
(7) by a tribe recognized by this State
(8) A driver's license or non-operators ID card issued by another state, District or territory of the US if voter's registration was within 90 days.
|Considering the contentious attitude of the liberal opposition, we ask you download a copy of these Voter ID options and SHARE THE LIST.
Get ready because this will certainly irritate you, but we think
it speaks to the character and attitude of our current


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The Sundance Film Festival is coming to an end and this year the swag houses were definitely the talk of the town.
We headed out to some of the most popular gift lounges from "The House Of Hype," where we caught up with 50 Cent and John Legend, to the In Touch Cafe / Stereo Lounge and the Kari Feinstein lounge. So how did the stars stay warm? By sipping Divine Chocolate Hot Cocoa!
In the meantime, check out our hilarious coverage of what really go down at these swag houses.