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排序方式: 共有138条查询结果,搜索用时 31 毫秒
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硅基材料是新一代高容量锂离子蓄电池负极材料的典型代表,近年来已成为理论研究和应用研究的热点.本文介绍了锂离子电池硅基负极材料的制备方法、电化学性能及其研究现状,分析了硅材料作为锂离子电池负极材料存在的问题;讨论了硅材料作为锂离子电池负极材料的研究前景.并指出若能克服目前存在问题,将有望成为新一代锂离子电池负极材料. 相似文献
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A new chemical method is reported for the determination of total fluoride in complex liquids and suspensions, such as fruit juices, urine, serum and blood. It is based on the formation of the A1F radical in a graphite furnace afterin situ oxygen-assisted ashing of the untreated sample. The absorbance of this radical is measured at 227.45 nm. The method is relatively easy to use and provides a low detection limit (14 ng/ml) and reasonable reproducibility (5–10%). 相似文献
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B. I. Camara 《Nonlinear dynamics》2013,73(3):1783-1794
In this paper, we use a food web model to investigate the effects of habitat loss and species diversity on ecosystem spatial structure and its elasticity. Our model incorporates functional responses based on the Holling-type-II and the modified Lesie–Gower schemes. Criteria for local stability, global stability of the nonnegative equilibria are obtained. The permanent coexistence of the three species is also discussed. Finally, by computer simulations, we find that far-from equilibria, environmental quality is positively correlated patterns complexity communities. Knowledge of the distribution shape of interacting communities will allow us to make better predictions of environmental quality. 相似文献
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Determination of the inhibitory effect of green tea extract on glucose‐6‐phosphate dehydrogenase based on multilayer capillary enzyme microreactor 下载免费PDF全文
Mohamed Amara Camara Miaomiao Tian Xiaoxia Liu Xin Liu Yujia Wang Jiqing Yang Li Yang 《Biomedical chromatography : BMC》2016,30(8):1210-1215
Natural herbal medicines are an important source of enzyme inhibitors for the discovery of new drugs. A number of natural extracts such as green tea have been used in prevention and treatment of diseases due to their low‐cost, low toxicity and good performance. The present study reports an online assay of the activity and inhibition of the green tea extract of the Glucose 6‐phosphate dehydrogenase (G6PDH) enzyme using multilayer capillary electrophoresis based immobilized enzyme microreactors (CE‐IMERs). The multilayer CE‐IMERs were produced with layer‐by‐layer electrostatic assembly, which can easily enhance the enzyme loading capacity of the microreactor. The activity of the G6PDH enzyme was determined and the enzyme inhibition by the inhibitors from green tea extract was investigated using online assay of the multilayer CE‐IMERs. The Michaelis constant (Km) of the enzyme, the IC50 and Ki values of the inhibitors were achieved and found to agree with those obtained using offline assays. The results show a competitive inhibition of green tea extract on the G6PDH enzyme. The present study provides an efficient and easy‐to‐operate approach for determining G6PDH enzyme reaction and the inhibition of green tea extract, which may be beneficial in research and the development of natural herbal medicines. Copyright © 2016 John Wiley & Sons, Ltd. 相似文献
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An experimental search for nuclear fusion inside imploding bubbles of degassed deuterated acetone at 0 degrees C driven by a 15 atm sound field and seeded with a neutron generator reveals an upper bound that is a factor of 10 000 less than the signal reported by Taleyarkhan et al. The strength of our upper bound is limited by the weakness of sonoluminescence, which we ascribe to the relatively high vapor pressure of acetone. 相似文献
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Using the linearized equations of the elastic continuum theory, simple formulae for the threshold voltage for the Freedericksz transition in planar films of the hexatic smectic I phase are derived. In contrast to the Freedericksz transition of a nematic film, this threshold strongly depends on the film thickness. The behaviour of the film in the weakly non-linear region slightly above the threshold is also considered to characterize the film instability. 相似文献