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排序方式: 共有4715条查询结果,搜索用时 437 毫秒
51.
Minshou Zhao Xinbo Zhang Yujun Chai Changying Sun 《Research on Chemical Intermediates》2006,32(5):403-417
The structures and the electrochemical characteristics of La0.7−x
CexMg0.3Ni2.8Co0.5 (x = 0.1–0.5) alloy, Ti0.25−x
ZrxV0.35Cr0.1Ni0.3 (x = 0.05–0.15) alloy and AB3<x<5-type alloy, which are the representative examples of AB3-type alloy, solid solution alloy and non-AB5-type alloy, respectively, have been investigated, and the performances of MH-Ni battery in which AB3<x<5 type alloy is used as the negative electrode material are examined at relatively low temperature. 相似文献
52.
J. L. Daft 《Journal of separation science》1983,6(9):480-487
Residue mixtures of pesticides in foods which were difficult to separate by packed-column gas chromatography were determined by capillary gas chromatography and electron capture detection. Manual injections of sample and reference standard were made with a 10 μL syringe on a septum-enclosed, split/ splitless inlet system. Optimal peak height repeatability (± 3%( was achieved with three-μL injections which were made within time periods of four hours or less. The average linearity coefficient (slope( obtained for detector response as a function of solution concentration was 1.1. 相似文献
53.
超临界流体萃取仪器的研制 总被引:1,自引:1,他引:1
本文报道了以国产原配件为基础,成功地研制了分析规模的超临界流体萃取仪器、并对仪器性能进行了全面考察,仪器性能稳定,重现性良好(RSD<3.1%),定量线性关系可靠,可满足定量萃取的要求。 相似文献
54.
Karen L. Kindle 《Applied biochemistry and biotechnology》1983,8(2):153-170
Thermostable α-amylases have application in a variety of industrial processes and enzymes from a substantial number of thermophilic
bacteria and fungi have been screened and characterized to varying degrees. The characteristics of these enzymes are summarized
in this review. The genetics of α-amylase production inBacillus subtilis is reviewed and classical and recombinant DNA approaches to increasing α-amylase production are discussed. 相似文献
55.
壳聚糖/聚丙烯酸聚电解质复合物膜对水/有机液体系的渗透汽化性能 总被引:8,自引:0,他引:8
以壳聚糖和聚丙烯酸为原料制备了聚电解质复合物膜,并对其分离水/乙醇体系的渗透汽化特性和浓度,温度,化学组成等因素的影响进行了研究,发现后处理方法对复合物膜的分离性能影响很大。同时对其它水/有机液体系,该膜也具备优异的分离性能。 相似文献
56.
脂肪族聚碳酸酯(PPC)与聚乳酸(PLA)共混型生物降解材料的热学性能、力学性能和生物降解性研究 总被引:3,自引:0,他引:3
通过溶液浇铸法制备了脂肪族聚碳酸酯与聚乳酸的共混物(PPC/PLA).采用示差热分析(DSC)和热重分析(TG)研究了材料的热性能.采用拉伸力学试验研究了共混物的力学性能.通过土壤悬浊拟环境培养降解实验法和扫描电子显微镜分析(SEM)对共混材料的生物降解性能进行了研究.实验结果表明,随着PPC含量的增加,共混物的拉伸强度和杨氏模量降低,而生物降解速率却显著提高.但是,在一定的降解时间内,某些比例共混物的降解速率比100%PPC还要快.综合分析表明,PPC/PLA是力学性能和降解性能可以互补的共混体系. 相似文献
57.
The main thermodynamic characteristics of the adsorption of haloadamantanes on graphitized thermal carbon black were determined by experimental measurements and by calculations in terms of molecular-statistic theory of adsorption. Using experimental data, the Kovac retention indices were calculated and the optimum conditions for gas-chromatographic separation of haloadamantanes on stationary phases with different polarity were elucidated. The influence of the cage effect in the adamantane unit on the chromatographic properties of haloadamantanes was established. 相似文献
58.
59.
Kyle Siegrist 《Journal of Theoretical Probability》1994,7(4):725-737
Three fundamental characterizations of the standard exponential distribution on [0, ) are the remaining life, memoryless and constant failure properties. Analogs of these properties are studied for distributions on a class of semigroups in which the semigroup operation replaces addition, a compatible partial order replaces the ordinary order, and a left-invariant measure replaces Lebesgue measure. Partial characterizations of exponential distributions on such semigroups are obtained and the semigroup formulation provides new characterizations of certain aging properties studied in reliability-increasing failure rate, new better than used, and increasing failure rate average. 相似文献
60.