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61.
An analytical method is presented for calculating the resonant frequency andQ-factor of a superconducting dielectric disk resonator operating in millimeter-wave regime with whispering-gallery mode. Resonant frequency shift due to the optical generation of quasi-particles in superconducting film is investigated as a function of photon flux. An optically tunable resonant frequency of about 500 MHz is estimated, and good agreement is found between numerical results and experimental ones.  相似文献   
62.
Montmorillinite clays, modified with either Zn(II) or Fe(III) chlorides have been used to catalyze the Friedel-Crafts alkylation of thiophene. High yields (ca. 80%) of 2- and 3-benzylthiophene mixtures were obtained using either catalyst in chlorobenzene or nitrobenzene solvent at 80°C. The ratio of 2–3-products was found to be controlled by their relative stability. Reactions were most rapid in nitrobenzene solution (<5 min) and resulted in formation of the 2-isomer as the only mono-substituted product. This is believed to be the first example in which an alkylation of thiophene has been limited to one regio-isomer.  相似文献   
63.
Spline regression is used to analyze the influence of radiation on the cancer probability in a group of participants of Chernobyl accident mitigation, depending on the exposure dose. A new method is proposed to approximate modified polygons by linear splines with two nodes. An algorithm for the identification of a transition point is outlined. __________ Translated from Kibernetika i Sistemnyi Analiz, No. 3, pp. 168–176, May–June 2006.  相似文献   
64.
论Oxymoron 及其翻译法   总被引:1,自引:0,他引:1  
英语的Oxymoron和Paradox都属于矛盾修辞的范畴,两者与汉语的反衬辞格颇为相似.通过大量的实例对英语语言中矛盾修辞的结构形式、语用功能分析与探讨后,揭示了矛盾修辞手段所表现的字面上似乎矛盾、互相排斥、互相对立的概念,发现其实际中所蕴含着令人深省的深刻哲理的一些语言现象,并对这一辞格的翻译方法进行了探讨.  相似文献   
65.
Using the CALPHAD (Calculation of Phase Diagram) technique, the DyCl3-MCl (M = Na, K, Rb, Cs) systems were optimized and calculated. The modified quasi-chemical model in the pair approximation for short-range ordering was used to describe the Gibbs energies of the liquid phase in these systems. From the measured phase diagram data and experimental thermodynamic properties, a series of thermodynamic functions were optimized base on an interactive computer-assisted analysis. The optimized parameters and the experimental data were thermodynamically self-consistent. The optimized results were discussed.  相似文献   
66.
袁珺 《肉类工业》2006,(5):15-16
主要目的是重新认识淀粉测定中的操作要点,并结合实践经验加以改进和完善,提高化验结果的准确度,更好地指导和监督生产。  相似文献   
67.
Molecular technologies have been developed for the transformation of barley. These technologies complement current methods of barley breeding. In addition, they offer the potential of altering specific components in barley that affect malting quality and of introducing foreign genes, controlling desirable traits, into barley. Application of genetic engineering to improving malt quality factors such as cell wall degradation, protein modification, starch hydrolysis and flavour stability, is discussed. Limitations to the use of this technology for improving malt-related functional properties of barley components such as cell walls and starch granules are also evaluated. Some possible constraints to the utilization of genetic engineering for malt quality improvements are identified.  相似文献   
68.
采用复合改性剂生产改性淀粉,制得干粉状NH—1粘合剂,并进行了工业化生产,取得了满意的结果。  相似文献   
69.
In order to improve the Zn homogeneity along the axial direction of CdZnTe boule, we have employed a modified Bridgman technique using a (Cd, Zn) alloy source in communication with the melt, whose temperature has been gradually changed from 800 to 840°C during growth. Electron probe microanalysis (EPMA) measurements of Zn composition in the boule shows an excellent homogeneity of Zn along the axis of the CdZnTe boule compared with results in a boule grown by using a fixed source temperature. We have performed a numerical simulation to obtain the approximate temperatures of additional heating and cooling needed to improve the radial Zn homogeneity. CdZnTe boule has been grown by seeded vertical Bridgman furnace with two zones of heater and cooler. Ultraviolet/visible spectroscopic measurements of Zn composition over the length of the boule indicate that the radial distribution of Zn composition is very homogeneous in the body region of the boule, where the radial variation of Zn composition is ±0.0005.  相似文献   
70.
Reduced ascorbic acid (RAA) content, total chlorophyll and green color retention, enzyme activities and texture changes were followed in broccoli spears packaged in polymeric film and nonpackaged during 96 hr storage (10°C). Concentrations within packages monitored by gas chromatography were (CO2,) 8% and (02) 10%. RAA retention, moisture content, total chlorophyll and color retention were greater in packaged broccoli. No differences were found between packaged and nonpackaged broccoli for ascorbate oxidase and peroxidase activities, or texture.  相似文献   
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