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461.
Valery Alexandrovich Astapenko 《Nuclear instruments & methods in physics research. Section B, Beam interactions with materials and atoms》2008,266(17):3744-3747
This paper is devoted to the theoretical investigation of polarization Bremsstrahlung (PB) from fast ions with electronic core scattering in a polycrystalline medium. There are two channels of radiation in this case, namely, projectile PB and target PB. Projectile PB is a new radiation mechanism due to the scattering of the own target electric field into a real photon on a bound electrons of the projectile. The main features of projectile PB from hydrogen-like multi-charged incident ions are studied, including spectral-angular distribution of PB photons and its dependence upon the projectile kinetic energy. 相似文献
462.
Valery Adzhiev Peter Comninos Maxim Kazakov Alexander Pasko 《Computer Animation and Virtual Worlds》2005,16(1):25-39
In this paper we describe an approach to computer‐aided sculpting concerned with the creation and modification of digital models based on physical abstract sculptures. We begin by presenting a survey of current methods for the creation of computer‐aided sculptured artefacts. Then we proceed to present some original methods and tools based on the function representation of geometric models. We introduce a specialized computer language, named HyperFun, which facilitates the modelling of complex objects. As well as presenting computer‐generated animated models of pre‐existing sculptures by Russian artist Igor Seleznev, we also show how some interesting novel shapes can be generated using the HyperFun system. Finally we outline two advanced projects concerned with creating a sculpture‐based augmented reality which allows for the interactive participation of the observer. In this paper, we present experimental results, which hopefully have some artistic appeal. These results were produced by an international team of researchers and students collaborating through the Internet. Copyright © 2005 John Wiley & Sons, Ltd. 相似文献
463.
This work presents a Tank in Series Reactor (TSR) model for the alkaline fuel cell operating in potentiostatic mode in cogeneration of H2O2 and electricity. The developed TSR model accounts for the component and the energy balances in gas channels, liquid alkaline and catalyst layers together with charge balances at electrode/electrolyte interfaces. The TSR model is able to predict the limiting two-dimensional profiles in alkaline fuel cell. The simulation results indicate the influence of mass transfer on the distribution of concentration, temperature and current density. 相似文献
464.
Melt dispersion mechanism for fast reaction of aluminum nano- and micron-scale particles: Flame propagation and SEM studies 总被引:1,自引:0,他引:1
Flame propagation studies for Al nanoparticles (80 nm) and micron particles (3–4.5 μm) mixed with MoO3 in both an open and confined burn setup were examined. A scanning electron microscopy (SEM) analysis of the reactants and products reveals quantitative size data that contributes toward an understanding of the governing reaction mechanisms. For the confined burn tube experiments, nanoscaled reactants exhibited a flame speed of 960 m/s, the same as has been reported in previous experiments. Micron scale particles exhibited a flame speed of 402 m/s, much higher than the 244 m/s obtained previously for 1–3 μm particles. These flame speeds are in quantitative agreement with predictions based on the recently developed melt-dispersion mechanism (MDM) describing the reaction of Al particles. It also demonstrates that some micron particles can reach flame speeds just 58% lower than the fastest nanoparticles, while micron scale particles are less expensive and do not have the pre-combustion safety and environmental issues typical of nanoparticles. The SEM analysis reveals a significant (at least by factor of 3.7 for nanoparticles) reduction in Al particle size post combustion, which is in agreement with the MDM and in contrast to the predictions based on diffusion mechanisms. Open burn experiments with nanoscale reactants have flame speeds of 12 m/s and product particle sizes almost as small as those in the burn tube experiments. However, the presence of some large particles, which may grow based on the diffusion mechanism, exclude evaporation and the homogenous nucleation mechanism. For open burn experiments with micron reactants, with flames speeds of 9 m/s, SEM analysis shows a molten-resolidified product with no distinguishable particles and cavities containing numerous nanoparticles with a measured diameter of 36 nm. 相似文献
465.
A three‐dimensional model is developed for an NO/H2 fuel cell cogenerating hydroxylamine and electricity. The model describes the distribution of velocity and concentration on the cathode side of the fuel cell, making the assumption of fuel excess on the anode side. The developed CFD‐based model is used for evaluation of various cathode flow field designs. Simulation results indicate the possibility of enhancing the fuel cell performance by decreasing the maldistribution of fields. A new cathode flow field design is developed for NO/H2 fuel cell with an improved performance for both energy and hydroxylamine production. Copyright © 2016 John Wiley & Sons, Ltd. 相似文献
466.
Murat K. Abdulakhatov Sergey Bartenev Nikolay Firsin Mikhail Goikhman Valery Guselnikov Yury Novikov Valery Romanovski Yury Sazanov Mikhail Zykov 《化学与化工:英文版》2014,(2):128-138
There is presented the review of publications connecting with creation of matrices for the immobilization of long-lived radionuclides and radioactive waste for storage and disposal, as well as for the transmutation. This paper substantiates the practicability and feasibility of obtaining the carbon matrces by carbonization of imidoderivatives. 相似文献
467.
Galina Shcherbakova Pavel Storozhenko Mariya Blokhina Valery Shatunov Denis Sidorov DmitrySidorov Gleb Yurkov 《化学与化工:英文版》2014,(3):232-242
Highly efficient synthesis methods have been developed and characteristics of nanometallocarbosilanes molecular structure were studied by the research team of GNIIChTEOS (State Research Institute for Chemistry and Technology of Organoelement Compounds). Nanometallocarbosilanes were synthesized by thermal co-condensation of oligocarbosilanes and alkyl amides of refractory metals. Initial, intermediate and final products of side reactions were characterized by 1H, 13C, 29Si NMR (nuclear magnetic resonance), IR (infra-red) spectroscopy, GPC (gel-penetrating chromatography), TGA (thermal gravimetric analysis), TEM (transmission electron microscopy), SEM (scanning electron microscopy), RES (X-ray phase analysis) and elemental analysis. The proposed synthesis method of nanometallocarbosilanes was lbund to produce fusable soluble organosilicon oligomers with homogeneous distribution of nanoscale (10-20 nm) metal particles in the oligomer matrix. A computational model of the group and elemental composition of nanometallocarbosilanes was developed; it was shown that they are molecular globules of near-spherical shape and rigid polycyclic structure. Thermochemical treatment of nanometallocarbosilanes leads to SiC-nanoceramics (a high yield of up to 75-80 mass%) modified by metal nanoparticles (20-30 nm) contributing to its stabilization. The application of preceramic oxygen-free nanometallocarbosilanes will make it possible to advance in solving the problem of ceramic composite materials with long-term resistance at temperatures above 1,500 ℃ in oxidizing environments. 相似文献
468.
469.
Somatic cell count (SCC) in milk is considered to be a valuable indicator of cow mastitis. For assessment of SCC in milk, the bioluminescent assay based on determination of ATP from somatic cells ([ATPsom]) in milk was proposed earlier. However, this assay is still not widely used in practice owing to lower reliability compared with conventional methods such as direct microscopy and flow cytometry. We revised the bioluminescent SCC assay and developed a simple protocol based on determination of the total non-bacterial ATP concentration in milk. It was shown that the novel ATP-releasing agent Neonol-10 (oxy-ethylated iso-nonyl phenol) has superior performance providing 100% lysis of somatic cells while not disrupting bacterial cells of milk at a concentration of 1.5% w/w. There was high correlation (R2=0.99) between measured bioluminescence and SCC as measured by direct microscopy. The observed detection limit of the bioluminescent milk SCC assay was as low as 900 cell/ml, time of analysis was 2-3 min per sample. The proposed method has high potential for on-site mastitis diagnostics. 相似文献
470.
Self‐standing electrodes are the key to realize flexible Li‐ion batteries. However, fabrication of self‐standing cathodes is still a major challenge. In this work, porous LiCoO2 nanosheet arrays are grown on Au‐coated stainless steel (Au/SS) substrates via a facile “hydrothermal lithiation” method using Co3O4 nanosheet arrays as the template followed by quick annealing in air. The binder‐free and self‐standing LiCoO2 nanosheet arrays represent the 3D cathode and exhibit superior rate capability and cycling stability. In specific, the LiCoO2 nanosheet array electrode can deliver a high reversible capacity of 104.6 mA h g?1 at 10 C rate and achieve a capacity retention of 81.8% at 0.1 C rate after 1000 cycles. By coupling with Li4Ti5O12 nanosheet arrays as anode, an all‐nanosheet array based LiCoO2//Li4Ti5O12 flexible Li‐ion battery is constructed. Benefiting from the 3D nanoarchitectures for both cathode and anode, the flexible LiCoO2//Li4Ti5O12 battery can deliver large specific reversible capacities of 130.7 mA h g?1 at 0.1 C rate and 85.3 mA h g?1 at 10 C rate (based on the weight of cathode material). The full cell device also exhibits good cycling stability with 80.5% capacity retention after 1000 cycles at 0.1 C rate, making it promising for the application in flexible Li‐ion batteries. 相似文献