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991.
Ian?A.?Castillo Richard?J.?MunzEmail author 《Plasma Chemistry and Plasma Processing》2005,25(2):87-107
Doped cerium oxide (CeO2) based electrolytes are attractive alternative materials to replace the existing yttria-stabilized zirconia (YSZ) used as electrolyte for SOFC (solid oxide fuel cells). Cerium oxide electrolytes offer a similar performance to YSZ electrolytes at a lower cell operating temperature (~600--800
°C), therefore reducing thermal stresses and solid state reactions among the cell components.Doped Ce1-xMexO2-x/2(Me = Gd, Sm or Y) fine \hbox{powders} were synthesized from nitrate salts dissolved in water using a radio frequency inductively coupled plasma reactor. It was demonstrated that the relative concentrations of Ce and dopants fed in the solutions were retained in the synthesized powders. The products were all nano-crystalline with the basic crystal structure of CeO2 and the crystal size of the products was essentially independent of the dopant used. The particle size distributions obtained were multimodal and in most cases trimodal. The results obtained differ from a previously reported mechanism of particle synthesis from liquid precursors. 相似文献
992.
N.?V.?KozhevnikovEmail author N.?I.?Kozhevnikova M.?D.?Gol'dfein 《Journal of Applied Spectroscopy》2005,72(3):329-333
The possibility of applying the turbidity-spectrum method and the conditions of its application in kinetic investigations
of emulsion polymerization are discussed. The necessity of taking into account the spectral dependence of the refractive index
of polymeric-monomeric particles and of a dispersion medium and multiple secondary light scattering as well as of using approximating
analytical expressions for the characteristic functions of light scattering is noted, because the refractive index of scattering
centers depends on the polymerization depth.
__________
Translated from Zhurnal Prikladnoi Spektroskopii, Vol. 72, No. 3. pp. 313–316, May– June, 2005. 相似文献
993.
The problem on the retrieval of sizes of an individual optically soft particle taken from binary mixtures of either oblate and prolate spheroids or cylinders and oblate spheroids is considered. It is based on multiangle scattered light intensity data. The multilevel neural networks method with a linear activation function and the method of the discrimination functions are used. Neural networks to retrieve characteristics of cylinders, oblate and prolate spheroids are designed. The errors in retrieved particle characteristics are investigated for the radius of an equivolume sphere in the range of 0.3-, shape parameter of spheroidal and cylindrical particles from -0.5 to 0.5 and 0 to 0.5, respectively. 相似文献
994.
Ya.?A.?Berdnikov V.?T.?Kim V.?F.?Kosmach M.?M.?RyzhinskiyEmail author V.?M.?Samsonov M.?E.?Zavatsky 《The European Physical Journal A - Hadrons and Nuclei》2005,26(2):179-184
Two important initial-state nuclear effects in hadron-nucleus collisions are considered. The ratios of inclusive differential
cross-sections for Drell-Yan dimuon production are calculated. The calculated results are compared to the E866 data. It is
shown that the consideration of multiple soft rescatterings of incident quarks in nuclei and initial-state quark energy loss
effects allow to get a good agreement between the calculated results and the experimental data. 相似文献
995.
A.?N.?IvanovEmail author M.?Cargnelli M.?Faber H.?Fuhrmann V.?A.?Ivanova J.?Marton N.?I.?Troitskaya J.?Zmeskal 《The European Physical Journal A - Hadrons and Nuclei》2005,23(1):1-6
Within the Nuclear Nambu-Jona-Lasinio model of light nuclei (the NNJL model), describing strong low-energy nuclear interactions, we compute the width of the energy level of the ground state of pionic deuterium. The theoretical value fits well the experimental data. Using the cross-sections for the reactions e + d p + p + e- and e + d p + n + e, computed in the NNJL model, and the experimental values of the events of these reactions, detected by the SNO Collaboration, we compute the boron neutrino fluxes. The theoretical values agree well with the experimental data and the theoretical predictions within the Standard Solar Model by Bahcall. We argue the applicability of the constraints on the astrophysical factor for the solar proton burning, imposed by helioseismology, to the width of the energy level of the ground state of pionic deuterium. We show that the experimental data on the width satisfy these constraints. This testifies an indirect measurement of the recommended value of the astrophysical factor for the solar proton burning in terrestrial laboratories in terms of the width of the energy level of the ground state of pionic deuterium. 相似文献
996.
997.
Alexander Gersten 《Foundations of Physics Letters》2000,13(2):185-192
By decomposing the mass squared operator for zero mass particles of spin s we obtain one-particle quantum equations for any spin on which 2s–1 subsidiary conditions are imposed. The derived equations are consistent with the two component neutrino equation and the Maxwell equations. Subsidiary conditions for the spins 1,
, and 2 are presented. 相似文献
998.
A New Tool for Eliminating Indoor Air Quality Complaints 总被引:1,自引:0,他引:1
Poor indoor air quality (IAQ) can cause a variety of health problems for building occupants including headaches, respiratory problems, eye irritation and fatigue. Traditional IAQ measurements often fail to identify the root cause of the problems and solutions remain elusive. A new IAQ metric, ultrafine particles, is shown to have a high correlation with complaint areas. Researchers are studying the toxicology of these tiny pollutants on animals and humans. Ultrafine particles are defined as particles smaller than 100nm diameter; nanoparticles, those smaller than 50nm diameter, are a subset of ultrafine particles. A battery-powered, portable condensation particle counter (CPC) can be used to quickly identify the source and transport pathways of ultrafine particle contaminants so they can be eliminated or controlled. The CPC condenses isopropyl alcohol on the particles to grow them to an optically detectable size. The hand-held instrument is fast responding, has a wide concentration range, and can log data to detect trends and short-term excursions. Adding the metric of ultrafine particles may become very important to IAQ investigations in the future. 相似文献
999.
R. Ferrini G. Guizzetti M. Patrini F. Nava P. Vanni C. Lanzieri 《The European Physical Journal B - Condensed Matter and Complex Systems》2000,16(2):213-216
GaAs Schottky diodes, made on semi-insulating liquid encapsulated Czochralski grown material with concentrations of acceptor
dopants varying from 1014 to 1017 cm-3, were investigated as alpha particle detectors. The charge collection efficiency (CCE) was found to decrease dramatically
with increasing . Optical spectra in transmittance and reflectance were accurately measured to determine the concentrations of both neutral
and ionised EL2 defects as a function of . The concentration of ionised EL2+ centres was shown to increase with , and to be quasi inversely proportional to the CCE values. This behaviour strongly supports the hypothesis that the EL2 defects
play the main role in the compensation of the material and in limitation of the detection properties.
Received 21 March 2000 相似文献
1000.
Yong‐Zhong Du Masato Kodaka 《Journal of polymer science. Part A, Polymer chemistry》2005,43(3):562-574
A novel biotinylated and enzyme‐immobilized nanobio device was prepared with heterobifunctional composite latex particles. Hemispherical poly(glycidyl methacrylate‐co‐divinylbenzene)/polystyrene [P(GMA‐DVB)/PSt] particles with epoxy and hydroxyl groups were prepared by soap‐free seeded emulsion polymerization with P(GMA‐DVB) seed particles. Hydroxyl groups were introduced to PSt chain terminals in the seeded stage by adding 2‐mercaptoethanol as a chain‐transfer agent. To obtain the desired hemispherical structure particles, we studied the effects of the preswelling process, the type and amount of solvents added in the seeded polymerization step, the weight ratio of the secondary monomer (styrene) to the seed particle (M/P), and the type of initiators. Under suitable conditions, heterobifunctional P(GMA‐DVB)/PSt was obtained, which was confirmed by observing the binding of streptavidin–colloidal gold with transmission electron microscopy (TEM). To obtain biotinylated and enzyme‐immobilized particles, 5‐(N‐succinimidyloxycarbonyl)pentyl D‐biotinamide was first reacted with the hydroxyl group on the PSt domain of the particle. Pyruvate kinase (PK) was then directly immobilized to the biotinylated particles through a reaction with the epoxy group in the PGMA domain. The monolayer of PK on the latex particle surface was considered to be formed by covalent binding. The activity of immobilized PK was almost conserved, even after being stored at 4 °C for 48 days. © 2004 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 43: 562–574, 2005 相似文献