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991.
992.
Dong  Manman  Qi  Honglan  Ding  Shengen  Li  Min 《Mikrochimica acta》2015,182(1-2):43-49
Microchimica Acta - A simple and sensitive electrochemical method was developed for the determination of trypsin by employing a specific heptapeptide (CRRRRRR) as a substrate. The positively...  相似文献   
993.
In this paper, we establish the analogue of Kolmogorov-type law of the logarithm for an array of independent random variables. The main methods are to develop the classic Bernstein’s and Kolmogorov’s inequality and replace the boundedness condition by conditions on the cumulant transform.  相似文献   
994.

In this study, the Cu-doped Ce?Mn/ATP denitration catalyst was prepared by impregnation method and heterogeneous precipitation method and its denitrification performance was tested. It was found that the denitrification effect was obviously improved after Cu doping. And the denitration effect of the catalyst prepared by the heterogeneous precipitation method was better and the denitrification rate was above 98%. Under this method, n(Cu: Mn) = 1 had the best denitration effect, with a maximum of 99.76%. The prepared catalysts were characterized by means of XRD, XPS, BET, and SEM. The results showed that CuMn2O4 and CuO appeared in the Cu doped catalysts. Moreover, the doping of Cu enriched the pore structure and surface morphology of the catalyst, so that the catalyst showed good denitrification performance.

  相似文献   
995.
996.
Journal of Radioanalytical and Nuclear Chemistry - Environmental impact of North Korea nuclear weapons testing on 3 Sept, 2017, is of key concern. In order to investigate whether there is...  相似文献   
997.
通过受限空间油气爆燃可视化实验发现,在不同初始油气体积分数下,爆燃火焰呈现出不同的表观特征,据此提出了受限空间油气爆燃的3种火焰形态,即光滑球形火焰、褶皱球形火焰和卷曲絮状火焰。分析了3种火焰形态的形成机理,并通过实验观测与理论分析,给出了区分3种火焰形态的临界条件。结合实验中采集到的关键参数,总结了不同的火焰形态下受限空间油气爆燃的反应产物、最大压力、升压速率、反应时间、火焰强度等关键参数的特征与变化规律。  相似文献   
998.
A simple, specific, and sensitive liquid chromatography–mass spectrometry (LC‐MS) method for determination of cyasterone in rat plasma was developed in our laboratory. Cucurbitacin B was used as an internal standard (IS). After protein precipitation with twofold volume of acetonitrile, the analyte and IS were separated on a Luna C18 column (100 × 4.6 mm, i.d., 3.0 µm; Phenomenex) by isocratic elution with acetonitrile–water (80:20, v/v) as the mobile phase at a flow rate of 0.4 mL/min. An electrospray ionization source was applied and operated in the positive ion mode; selected ion monitoring scan mode was used for quantification, and the target ions m/z 543.3 for cyasterone and m/z 581.3 for IS were chosen. Good linearity was observed in the concentration range of 0.40–400 ng/mL for cyasterone in rat plasma. Intra‐day and inter‐day precision were both <7.4%. This method was proved to be suitable for pharmacokinetic studies after oral (5.0 mg/kg) or intravenous (0.5 mg/kg) administration of cyasterone in rats. Copyright © 2015 John Wiley & Sons, Ltd.  相似文献   
999.
In this paper, a topological classification of piecewise monotone functions(abbreviated as PM functions) with nonmonotonicity height equal to 1 which are strictly increasing on their characteristic intervals and have finitely many fixed points is presented.  相似文献   
1000.
To ensure safe and effective amplification for the chirped pulse amplification laser facility, many factors such as pulse spectral width, pulse duration, grating parameters and incidence angle parameter are considered carefully in the design of the pulse stretcher. A compact four pass Offner stretcher design is given out. Experiment results show that the stretcher has broad spectral width, large stretching ratio and high transmission efficiency. By comparison, the calculated result of the dispersion effect on the pulse duration is completely consistent with the experiment result.  相似文献   
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