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81.
The possibility of optimum filtration of the radiation of a mercury arc lamp for subterahertz Hilbert-transform spectroscopy with a frequency-selective Josephson detector is demonstrated. Hilbert-transform spectroscopy was used for the first time for measuring the transmission spectrum of a high-pass filter. 相似文献
82.
V. G. Shengurov S. P. Svetlov V. Yu. Chalkov B. A. Andreev Z. F. Krasil'nik B. Ya. Ber Yu. N. Drozdov 《Inorganic Materials》2003,39(1):3-5
The Ge and Er depth profiles in Si1 – x
Ge
x
layers grown on Si(100) substrates by Si sublimation-source molecular-beam epitaxy in GeH4 were studied by secondary ion mass spectrometry. The results demonstrate that Ge facilitates Er incorporation into the growing Si–Ge layer. The Er dopant profile becomes sharper with increasing Ge content. The Ge profile also has rather sharp boundaries, indicating that there is no Ge surface segregation, which is attributable to the presence of adsorbed hydrogen, acting as a surfactant. 相似文献
83.
84.
85.
86.
Processes of corrosion cracking of the metal of turbine blades in the region of initial steam condensation are considered. Possible ways of preventing corrosion-fatigue damage to the blades are proposed. 相似文献
87.
Zhi‐Long Ye Min Lu Yan Zheng Ya‐Hong Li Wei‐Min Cai 《Journal of chemical technology and biotechnology (Oxford, Oxfordshire : 1986)》2008,83(11):1541-1550
BACKGROUND: Food waste generally has a high starch content and is rich in nutritional compounds, including lipids and proteins. It therefore represents a potential renewable resource. In this study, dining‐hall food waste was used as a substrate for lactic acid production, and response surface methodology was employed to optimise the fermentation conditions. RESULTS: Lactic acid biosynthesis was significantly affected by the interaction of protease and temperature. Protease, temperature and CaCO3 had significant linear effects on lactic acid production, while α‐amylase and yeast extract had insignificant effects. The optimal conditions were found to be an α‐amylase activity of 13.86 U g?1 dried food waste, a protease activity of 2.12 U g?1 dried food waste, a temperature of 29.31 °C and a CaCO3 concentration of 62.67 g L?1, which resulted in a maximum lactic acid concentration of 98.51 g L?1 (88.75% yield). An increase in inoculum size would be appropriate for accelerating the depletion of initial soluble carbohydrate to enhance the efficiency of α‐amylase in dining‐hall food waste fermentation. CONCLUSION: A suitable regression model for lactic acid production was developed based on the experimental results. Dining‐hall food waste was found to be a good substrate for lactic acid fermentation with high product yield and without nutrient supplementation. Copyright © 2008 Society of Chemical Industry 相似文献
88.
E. Ya. Davydov I. S. Gaponova T. V. Pokholok G. B. Pariiskii G. E. Zaikov 《应用聚合物科学杂志》2008,108(1):128-133
The features of initiation of free radical reactions in polymers by dimers of nitrogen dioxide are considered. The conversion of planar dimers into nitrosyl nitrate in the presence of amide groups of macromolecules has been revealed. Nitrosyl nitrate initiates radical reactions in oxidative primary process of electron transfer with formation of intermediate radical cations and nitric oxide. As a result of subsequent reactions, nitrogen‐containing radicals are produced. The dimer conversion has been exhibited by estimation of the oxyaminoxyl radical yield in characteristic reaction of p‐benzoquinone with nitrogen dioxide on addition of aromatic polyamide and polyvinylpyrrolidone to reacting system. The isomerization of planar dimers is efficient in their complexes with amide groups, as confirmed by ab initio calculations. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci, 2008 相似文献
89.
Bednars'ka L. M. Horelenko Yu. K. Kovbuz M. O. Hertsyk O. M. Kotur B. Ya. Nosenko V. K. 《Materials Science》2003,39(2):291-294
Alloying of amorphous Fe-Me-Si-B metallic compositions with nickel and molybdenum results in a decrease in the values of saturation magnetization in fields with a magnetic intensity of 0.72 MA/m. The same alloying additions decrease the temperature of formation of new magnetic Fe3B-type phases, which are stable up to 873 ± 5 K. 相似文献
90.
L. V. Ravichev A. V. Bespalov V. Ya. Loginov 《Theoretical Foundations of Chemical Engineering》2008,42(3):314-323
A mathematical model for calculating the viscous properties of concentrated suspensions characterized by particle sizes of 30 to 800 µm), solids volume fractions of 1 to 70 vol %, different particle-size distributions, and a shear-rate range of 0.16 to 437 s?1, which can describe the time evolution of the properties, is proposed. The model can be applied to calculating the viscous properties of catalyst oxide pastes, particulate-filled polymeric pastes, and the like. 相似文献