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101.
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Podchernyaeva Irina A. Panasyuk Alla D. 《Powder Metallurgy and Metal Ceramics》2000,39(11-12):554-559
Studies have been done on how various concentrated energy forms (spark discharge and laser beam) affect the formation, composition, and structure of coatings made from the new composite material TiB2 ― AlN (1:1). The working surfaces have been examined by x-ray phase analysis, microprobe, and metallography. It is found that the composition and structure of a spark coating differ from those of the depositing electrode. The TiB2 ― AlN material is recommended for hardening low-carbon steels. 相似文献
103.
Polyaniline is one of the most important conducting and responsive polymers. A molecular mechanism for the oxidation of aniline is proposed. This mechanism explains the specific features of aniline oligomerization and polymerization in various acidity ranges. The formation of polyaniline precipitates, colloids and thin films is reviewed and discussed on the basis of the chemistry of aniline oxidation. The generation of nanostructures, i.e. granules, nanotubes, nanowires and microspheres, is also considered. Oligomers containing phenazine constitutional units play an important role in self‐assembly to form templates. Polyaniline chains then grow from these templates and produce the various individual morphologies. Copyright © 2008 Society of Chemical Industry 相似文献
104.
Irina V. Ovsienko Lyudmila Yu. Matzuy Nykolai I. Zakharenko Nykolai G. Babich Tetyana A. Len Yuriy I. Prylutskyy David Hui Yuri M. Strzhemechny Peter C. Eklund 《Nanoscale research letters》2008,3(2):60-64
It is shown that magnetometry can be employed as an effective tool to control the content of a ferromagnetic constituent in
nanocarbon materials. We propose a thermochemical treatment protocol to achieve extensive cleaning of the source nanocarbon
materials from ferromagnetic refuses. 相似文献
105.
Tat'yana V. Volkova Yakov S. Vygodskii Olesya N. Zabegaeva Yan V. Zubavichus Marina N. Il'ina Alexander P. Krasnov Ol'ga V. Afonicheva Elena I. Lozinskaya Irina A. Garbuzova Alexander S. Shaplov 《应用聚合物科学杂志》2009,114(1):577-586
Anionic polymerization of ε‐caprolactam was performed in the presence of only 5 wt % of aromatic polyimides having five‐ and six‐membered imide cycles and bearing hexafluoroisopropylidene, ether, fluorene, siloxane, phthalide, or SO3H? groups, both in the polymer backbone and as side moieties. The synthesized new copolymers were fully characterized by IR spectroscopy, thermomechanical analysis, dilatometry, and X‐ray diffraction. Tough and frictional properties of the obtained copolymers were estimated as well. It was found that on the selection of polyimide activator it is possible to gain the desirable control over the polymer properties, namely the gel‐fraction content, phase composition, compression modulus, notched Izod impact strength, temperature of frictional contact, friction coefficient, etc. These investigations will facilitate the choice of the optimum macromolecular activator for the modification of both the synthetic method and the properties of the commercial polycaproamide. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2009 相似文献
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107.
L. N. Maskaeva V. F. Markov I. M. Morozova N. M. Barbin V. Ya. Shur E. I. Shishkin E. S. Samoĭlova 《Technical Physics Letters》2008,34(6):472-474
Thin films of supersaturated Zn x Pb1 ? x S solid solutions containing up to 4.1 mol % ZnS have been obtained by hydrochemical deposition. The dependence of the material structure and surface morphology on the film composition has been studied. It is established that an increase in the content of zinc sulfide leads to the growth of grains with a more complicated crystalline structure, the formation of grain boundary fragments with dimensions from 60 to 100 nm, and a modification of the electrical properties of deposited layers. 相似文献
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