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101.
Garegin R. Karagedov Svetlana S. Shatskaya Nikolai Z. Lyakhov 《Journal of Materials Science》2007,42(18):7964-7971
Reasons for a phase transition in zirconia subjected to intensive mechanical treatment in planetary mill have been considered.
If steel balls and vials are used for milling the comminution is accompanied by oxidation of wear metal particles and successive
mechanochemical reaction with ZrO2. Aluminum has been shown to behave similarly and, being deliberately added to zirconia powder, to form solid solutions. Foreign
metal cations introduced into the lattice stabilize a modification with higher crystal symmetry thus increasing the threshold
size above which the monoclinic modification is stable. An increase of surface energy contribution to the Gibbs’ energy of
zirconia plays an important role in phase transformation at the initial stages of mechanical treatment, while henceforth thermodynamic
stability is more and more determined by the stabilizing effect of the impurity cations. Under the conditions that rule out
contamination of ZrO2 with wear material or other metal additives, dynamic equilibrium sets in between the direct transition to the tetragonal
phase and the reverse transition to the monoclinic form. 相似文献
102.
103.
The three-dimensional (3D) model of a feedforward neural network(NN) based on so called N-hypercube topology isproposed. The N-hypercube is different from theclassical hypercube used in communication theory, and in Booleanalgebra. This new structure has been created based on a novelalgorithm for embedding a binary decision tree and binary decisiondiagram into a N-hypercube. It is shown thatN-hypercube topology is a reasonable solution toimplement NN of threshold gates, in particular, on thesingle-electron devices. The 3D design methodology of feedforwardNN is oriented to technology mapping to nanodevices. Results ofextensive experimental study of feedforward networks consistingof over 3500 N-hypercubes are presented. 相似文献
104.
Jaroslav Stejskal Mária OmastováSvetlana Fedorova Jan ProkešMiroslava Trchová 《Polymer》2003,44(5):1353-1358
Polyaniline and polypyrrole have been prepared by chemical oxidative polymerization of the corresponding monomers in an aqueous medium containing an anionic surfactant—sodium bis(2-ethylhexyl) sulfosuccinate, dodecylbenzenesulfonic acid and its sodium salt, and sodium dodecyl sulfate. Determination of the yield, elemental composition and density proved, and FTIR spectroscopy confirmed, that the anionic surfactants become incorporated in the conducting polymers. The polymerizations in the presence of a cationic surfactant, tetradecyltrimethylammonium bromide, were carried out for comparison. While the conductivity of polypyrrole became enhanced after the introduction of an anionic surfactant, the changes in the conductivity of polyaniline were marginal. The conductivity changes in both polymers during thermal ageing were measured at 175 °C. The electrical stability of polyaniline was better than that of polypyrrole. The presence of a surfactant improved the stability of conductivity of polypyrrole but reduced the electrical stability of polyaniline. 相似文献
105.
BA Mannion TV Kolesnikova SH Lin S Wang NL Thompson ME Hemler 《Canadian Metallurgical Quarterly》1998,273(50):33127-33129
The 80/40-kDa CD98 protein complex was purified using an anti-CD98 heavy chain monoclonal antibody coupled to Sepharose beads. Eluted proteins were subjected to preparative SDS-polyacrylamide gel electrophoresis, and protein corresponding to the 40-kDa CD98 light chain was excised. Following proteolysis with trypsin, a peptide fragment was sequenced by mass spectrometry. The nine residues obtained were identical to established C-terminal sequences of the human E16 and rat TA1 proteins, suggesting that TA1/E16 protein is the CD98 light chain. Consistent with this, anti-TA1/E16 antibodies specifically immunoblotted the approximately 35-40-kDa light chain present upon immunoprecipitation of the human CD98 complex. Furthermore, anti-CD98 heavy chain antibody specifically co-immunoprecipitated hemagglutinin-tagged light chain from cells transfected with hemagglutinin-tagged E16 cDNA. In conclusion, the CD98 light chain is identical to the TA1/E16 protein, based on partial amino acid sequence identity, antibody cross-reactivity, genetic reconstitution evidence, similar molecular size, and comparable cell distribution. 相似文献
106.
107.
Mark Q. Snyder Svetlana A. Trebukhova Boris Ravdel M. Clayton Wheeler Joseph DiCarlo Carl P. Tripp William J. DeSisto 《Journal of power sources》2007
Lithium titanate spinel (Li4Ti5O12, or LTS) is receiving consideration as a nanopowder anode material for use in lithium-ion batteries. LTS has more positive working potential than traditional graphite anodes, and it does not react with electrolyte components. However, the main drawback of LTS powder is its poor interparticle electronic conductance that reduces the high-rate ability of the electrode. To improve this we have coated the surface of the LTS powder with a titanium nitride layer by atomic layer deposition (ALD). In situ infrared spectroscopy studies were conducted to confirm the attachment of the titanium precursor. The nitrogen content of films was measured by total nitrogen content testing. Transmission electron microscopy (TEM) micrographs confirmed the formation of a thin titanium nitride film around LTS particles by ALD. Finally, lithium cells with electrodes made of original and modified LTS nanopowders were assembled and tested. 相似文献
108.
Yu. A. Buevich N. A. Kolesnikova A. N. Tsetovich 《Journal of Engineering Physics and Thermophysics》1978,35(3):1036-1041
The gas-flow distribution is examined for a set of identical equidistant flat jets entering a deep immobile or fluidized bed.Translated from Inzhenerno-Fizicheskii Zhurnal, Vol. 35, No. 3, pp. 424–431, September, 1978. 相似文献
109.
110.
Yu. A. Buevich N. A. Kolesnikova G. A. Minaev 《Journal of Engineering Physics and Thermophysics》1977,33(4):1136-1143
Formulation of problems about the flow generated by jets in a fixed or fluidized granular bed is discussed. The solution of such a problem is considered for a single plane jet in a high layer.Translated from Inzhenerno-Fizicheskii Zhurnal, Vol. 33, No. 4, pp. 586–595, October, 1977. 相似文献