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91.
The behaviour of adsorbed CO on Ru(001) flat and Ru(l,1,10) stepped surfaces in the CO pressure range between 10?6 and 101 Pa has been investigated by TDS, AES, LEED and UPS. The disproportionation of CO proceeds rapidly on the stepped surface and its apparent activation energy was obtained to be 20 kJ mol?1 at nearly zero coverage. The carbon species produced by CO disproportionation show non-uniform reactivity with 18O2 and provide four CO desorption peaks in TPR spectra, which are assigned to α-C18O,ß-C18O and those derived from carbidic and graphitic carbons. At smaller carbon coverage, only α-CO and β-CO were observed, but with increasing coverage the amount of ß-CO reaches a maximum and carbidic carbon is newly formed. Further increase of carbon deposition gives graphitic carbon. The conversion from carbidic to graphitic carbon and the dissolution into the bulk took place upon heating to 1000 K. It is remarkable that very active carbon species are converted to molecular CO through the reaction with O2 even at low temperature such as 200 K. It was also confirmed that active carbon species are formed on Ru surface during COH2 reaction. 相似文献
92.
The transport properties in a-InxSe1?x films have been studied by a time of flight method. The drift parameters sharply decreases with small addition of In (0.5 at.%) and become almost constant with further progressive increase of In, while the transit time dispersion of electron simultaneously increases. The experimental results are explained by an increase in the number of shallow and deep traps generated by the introducing of In. 相似文献
93.
94.
Control of very low oxygen partial pressures was performed in the range of 10−21-10−24 Pa at 750°C by pumping oxygen into the purified hydrogen stream with a stabilized zirconia cell. The oxygen partial pressures were monitored by a stabilized zirconia sensor. The stabilized zirconia oxygen sensor was calibrated by H2-CO2 gas buffer mixture in the range of oxygen pressure from 10−17 to 10−21 Pa, and oxygen partial pressures below 10−21 Pa were measured by extrapolating the calibration line to very low oxygen partial pressures. The lowest oxygen partial pressure controlled was 10−24 Pa at 750°C, which was limited by gas leaks in the system and also by the reduction of the ionic transference number in solid electrolyte used as the oxygen pump. 相似文献
95.
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98.
We introduce certain families of elliptic functions involving the Weierstrass ℘-function via q-series systematically and investigate their analytic and algebraic properties. Especially, we give examples of non-linear
algebraic ordinary differential equations satisfied by some such elliptic functions.
2000 Mathematics Subject Classification: Primary–11M36, 33E05 相似文献
99.
We introduce a generalized notion of the zeta regularization. As applications we show the quantum analogue of the Lerch formula
and of the Dirichlet class number formulas. We also give some further examples related to Appell's O-functions.
2000 Mathematics Subject Classification: Primary—11M36
Work in part supported by Grant-in Aid for Scientific Research (B) No. 11440010, and by Grant-in Aid for Exploratory Research
No. 13874004, Japan Society for the Promotion of Science. 相似文献
100.
Yoshimasa Hirata Hisao Nakata Kiyoyuki Yamada Kunio Okuhara Takayuki Naito 《Tetrahedron》1961,14(3-4):252-274
The structure of aureothin, the third nitro compound obtained from nature, has been elucidated as I. Several reactions of aureothin and its derivatives are described. 相似文献