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排序方式: 共有195条查询结果,搜索用时 31 毫秒
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Peter Ettmayer Walter Schebesta Alfred Vendl Richard Kieffer 《Monatshefte für Chemie / Chemical Monthly》1978,109(4):929-941
The System V–Cr–N has been investigated at 1100 and 1400 °C and at nitrogen pressures between 1 and 1000 atmospheres by X-ray techniques. VN and CrN on the one hand and V2N and Cr2N on the other are forming complete series of solid solutions. The phase field of the mononitride solid solution is dependent on nitrogen pressure and temperature conditions.
Auszug aus der Diplomarbeit des Herrn Dipl.-Ing. Dr.W. Schebesta. 相似文献
Auszug aus der Diplomarbeit des Herrn Dipl.-Ing. Dr.W. Schebesta. 相似文献
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LoSecco JM Bionta RM Biewitt G Bratton CB Casper D Chrysicopoulou P Claus R Cortez BG Errede S Foster GW Gajewski W Ganezer KS Goldhaber M Haines TJ Jones TW Kielczewska D Kropp WR Learned JG Lehmann E Park HS Reines F Schultz J Seidel S Shumard E Sinclair D Sobel HW Stone JL Sulak L Svoboda R van der Velde JC Wuest C 《Physical review letters》1985,54(21):2299-2301
6.
By metal impregnation of selected naturally occurring organic materials followed by controlled carbonization, metal semicoke catalysts can be readily prepared. These catalysts have been tested in the synthesis of hydrocarbons and alcohols from CO/H2 and CO2/H2 mixtures. Fe and Co preparations have been used. Relatively high temperatures are required when using these catalysts, which are quite active for synthesis using CO2 and H2. The pressure (5150 kPa) is very favorable both for the synthesis of liquid hydrocarbons (C5–C30) and alcohols (C1–C5).
. CO/H2 CO2/H2. Fe Co. , CO2 H2. 5150 ) (C5–C30) (C1–C5).相似文献
7.
K. Hayashi A. Droulde F. Kieffer 《Journal of polymer science. Part A, Polymer chemistry》1969,7(1):83-99
The trapping of electrons and styrene cations and anions has been studied in a methylcyclohexane glass by the techniques of deferred luminescence. Radiothermoluminescence curves consist of two peaks, at 90 and 95°K, in this matrix. The second peak increases linearly with styrene concentration up to 2 × 10?2M when it reaches a constant value, whereas the first peak increases from 10?4 to 10?3M and then decreases at higher concentrations and is not discernible at concentrations above 10?2M. We propose two mechanisms which are qualitatively consistent with this behavior and are based essentially on the recombination of styrene cations with thermally detrapped electrons in the first peak and with anions in the second peak. Photothermoluminescence (i.e., thermoluminescence after photoionization with ultraviolet light) similarly consists of the 90 and 95°K peaks for a 10?3M solution and of the 95° peak alone for a 10?d M solution. Radiophotoluminescence excitation spectra at 77°K, corresponding to absorption spectra of trapped electrons and styrene anions, show that anions are the predominant negative species in 10?2 molar solution, and trapped electrons in 10?3 molar solution. Spectral analysis of radiothermoluminescenece shows the presence of two emission bands, one of which is identical with styrene fluorescence excited by the 254 Nm mercury line (λmax = 292, 302, 307, and 317 Nm). The other band has three fairly poorly resolved maxima at 474, 486 and 496 nm and seems to correspond to the fluorescence of C6H5?H-CH3 radicals formed during radiolysis. 相似文献
8.
Manfred Schreiner Peter Ettmayer Richard Kieffer 《Monatshefte für Chemie / Chemical Monthly》1982,113(8-9):869-876
Molybdenum-tungsten-carbonitrides can be prepared by reacting prealloyed powders of Mo and W with carbon in the presence of nitrogen or ammonia. Single phase carbonitrides (Mo, W) (C, N) with the WC-type structure can be obtained. The nitrogen content of these carbonitrides increases with increasing molybdenum content. Flowing ammonia has a decarburizing effect, which has to be counterbalanced by an addition of a carbonaceous gas such as methane. Nitrogen instead of ammonia is equally effective and gives carbonitrides which have a nitrogen content only insignificantly lower than the carbonitrides obtained in flowing ammonia. The lattice parameters of the carbonitrides are found to be slightly smaller than the lattice parameters of the corresponding carbides. 相似文献
9.
Zusammenfassung Mit Hilfe von Neutronenbeugungs-Aufnahmen an hydrierten und deuterierten Übergangsmetall-Carbiden wurden die Positionen der Kohlenstoff- und Wasserstoffatome ermittelt. In den ternären Phasen Zr2C1-x
Hy y und Zr2C1-x
D
y
besetzen H bzw. D die tetraedischen Lücken des Anti-CdJ2-Typs. In der kubischen Carbohydrid-Phase liegt der Kohlenstoff geordnet vor; der Wasserstoff füllt vorzugsweise die freien Oktaederlücken.
Mit 4 Abbildungen 相似文献
The positions of H and D have been determined in hexagonal carbohydrides by means of neutron diffraction experiments, the H(D-)-atoms filling the tetrahedral voids of the Anti-CdI2-type. Carbon and most of the hydrogen (deuterium) are filling the octahedral voids of the cubic carbohydrides.
Mit 4 Abbildungen 相似文献
10.