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排序方式: 共有188条查询结果,搜索用时 46 毫秒
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影响锂离子电池安全性的因素 总被引:12,自引:0,他引:12
锂离子电池的安全性一直是锂离子电池 ,特别是大型锂离子电池研制、生产、使用中的关键性问题 ,通过对锂离子电池的材料、制造工艺以及使用条件等方面的探讨 ,分析影响锂离子二次电池安全性的各种因素 相似文献
33.
David C. Johnson II 《Tetrahedron letters》2004,45(46):8483-8487
The benzyl groups of β-hydroxy-N-benzyl sulfonamides are labile toward hydrogenolysis-unlike N-benzyl sulfonamides lacking the β-hydroxy moiety. We find that N-acyl-N-benzyl sulfonamides undergo hydrogenolysis under very mild conditions. Based upon these observations, we developed a reversible safety-catch method using tert-butoxycarbonyl moieties to activate N-benzyl sulfonamides toward hydrogenolysis. We also explored the utility of the safety-catch activation method for other nitrogen-based functionality such as N-benzyl carboxamides, imides, and related functionality. 相似文献
34.
Following the recent progress in NMR imaging of the foetus in utero an investigation has been made of the effect of exposure to strong pulsed magnetic fields on the pregnancy of mice and the post natal development of their litters. 23 pregnant mice received exposures ranging from 3.5-12kT/s with pulse periods in the range 0.33-0.56ms at various times during gestation. A similar number of pregnant mice served as controls. No adverse effect was observed on the pregnancy. There was no significant difference between the litter numbers and growth rates of the exposed litters compared with controls. The implications of these results are discussed with regard to the safety of NMR imaging during pregnancy. 相似文献
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Questionnaire-based surveys are a standard method used for assessing the safety climate within an organization. However, their analysis – in particular data aggregation – poses several challenges, among which are subjective judgment, incompleteness and uncertainty. This paper explores the use of approaches based on belief structures for aggregating data from safety climate questionnaires. Data relevant to this study were collected through a questionnaire administered to the employees of a nuclear research centre. The results show that, while belief structures may offer a promising way to represent data collected from questionnaires, the existing aggregation methods are not always adequate. Averaging schemes applied to belief structures seem the most suited – among the methods investigated – in the specific problem context analyzed. The analysis of the survey data shows the limitations of quantitative approaches for safety culture assessment and the need to always complement these with in-depth qualitative analysis. 相似文献
37.
《Comptes Rendus Mecanique》2017,345(10):712-723
This paper deals with the robust safety design optimization of a rail vehicle system moving in short radius curved tracks. A combined multi-objective imperialist competitive algorithm and Monte Carlo method is developed and used for the robust multi-objective optimization of the rail vehicle system. This robust optimization of rail vehicle safety considers simultaneously the derailment angle and its standard deviation where the design parameters uncertainties are considered. The obtained results showed that the robust design reduces significantly the sensitivity of the rail vehicle safety to the design parameters uncertainties compared to the determinist one and to the literature results. 相似文献
38.
《无机化学与普通化学杂志》2018,644(16):888-892
The sensitivity of an energetic compound gives its vulnerability to accidental detonation, which is caused by an unintended stimulus. Shock and electric spark sensitivities of energetic compounds are two important sensitivity parameters for assessment of their safety in working places. Several correlations are introduced for reliable prediction of shock sensitivities of energetic compounds at 90, 95, and 98 % of theoretical maximum density (TMD) according to NSWC using Navy small‐scale gap test through their electric spark sensitivities. For 11 explosives, where experimental data of both shock and electric spark sensitivities were available, the predicted results at 90 % of TMD are compared with the quantum mechanical approach. The root‐mean‐square (rms) deviations of the new and complex quantum mechanical methods at 90 % TMD are 2.38 and 3.95 kbar, respectively, which confirmed the high reliability of the new method. For high explosives with 90, 95, and 98 % TMD, it will be shown that the predicted results of the new method are also much more reliable than one of the best available empirical approaches. A correlation between shock sensitivities on the basis of aluminum gaps with different thicknesses and the pressure required to initiate material pressed to 90 % TMD is also derived. 相似文献
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In this paper, we first generalize reachability constraints for linear differential equations, then tighten them by using the information of multiplicity of the eigenvalues and eigenvectors of such equations and put them into our constraint based approach for safety verification of hybrid systems that employs recursive reasoning to improve the method of constraint propagation based abstraction refinement. 相似文献
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