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111.
PBXN-5传爆药安全可靠性试验方法研究 总被引:1,自引:0,他引:1
为满足引信传爆序列对高可靠性、高安全性火工药剂的需求,通过小隔板试验及升降法试验对PBXN-5传爆药的输出能力和冲击波感度作了分析和研究,小样本试验发现:当施主药柱装药相同,随施主与受主间隔板厚度增加,可靠起爆概率明显降低;但随受主药柱的装药尺寸的减小,传爆概率却增大。总之,受主药柱直径越小,隔板越薄,使用可靠性越高,结合安全使用性,计算得到合适的可靠度数据,为微型火工品装药提供参数依据。 相似文献
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Lijie Zhou Hongwu Wang Zhiqiang Zhang Jian Zhang Hongbin Chen Xuejun Bi Xiaohu Dai Siqing Xia Lisa Alvarez-Cohen Bruce E. Rittmann 《Frontiers of Environmental Science & Engineering》2021,15(1):16
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为从安全生产大数据中挖掘安全规律并最终提炼安全生产基础原理,首先在对安全生产大数据的定义及其内涵进一步阐释基础上,提出安全生产大数据采集的定义,并将其分解为3个过程;然后提出安全生产大数据的5W2H采集法,并对其内涵(采集原因,使用主体、采集者及采集对象,采集数据类型,采集边界,采集时间,采集数据量及其采集方法)进行详细分析;最后以思维路径为主、过程路径和技术路径为辅,建立安全生产大数据采集的一般模式。结果表明,安全生产大数据采集模式的研究可为安全生产大数据的存储、处理及其应用提供基础。 相似文献
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Zhuoying WU Qing WANG Feng GUO Shenghua ZHANG Qipei JIANG Xin YU 《Frontiers of Environmental Science & Engineering》2014,8(2):205-214
Often as a result ofbiofilm formation, drinking water distribution systems (DWDS) are regularly faced with the problem of microbial contamination. Quorum sensing (QS) systems play a marked role in the regulation of microbial biofilm formation; thus, inhibition of QS systems may provide a promising approach to biofilm formation control in DWDS. In the present study, 22 bacterial strains were isolated from drinking water-related environments. The following properties of the strains were investigated: bacterial biofilm formation capacity, QS signal molecule N-acyl-L-homoserine lactones (AHLs) production ability, and responses to AHLs and AHL analogs, 3-chloro-4-(dichloromethyl)-5-hydroxy-2(5H)- furanone (MX) and 2(5H)-furanone. Four AHLs were added to developed biofilms at dosages ranging from 0.1 nmol.L J to 100nmol.L1. As a result, the biofilm growth of more than 1/4 of the isolates, which included AHL producers and non-producers, were significantly promoted. Further, the biofilm biomasses were closely associated with respective AHLs concentrations. These results provided evidence to support the idea that AHLs play a definitive role in biofilm formation in many of the studied bacteria. Meanwhile, two AHLs analogs demon- strated unexpectedly minimal negative effects on biofilm formation. This suggested that, in order to find an applicable QS inhibition approach for biofilm control in DWDS, the testing and analysis of more analogs is needed. 相似文献
118.
Many substances react with water in such a way that flammable gases are formed. For transport issues this reaction may possess a considerable hazard especially if the cargo is wetted by rain or by water from other sources. In the UN Recommendations on the Transport of Dangerous Goods these kinds of problems are addressed. The UN test N.5 “Test method for substances which in contact with water emit flammable gases” corresponds to this hazard. Classification according to the test method is done by measurement of the gas evolution rate of the flammable gas by any suitable procedure. At BAM a gravimetric approach is used to measure the gas evolution rate. In this paper we present the evaluation of the apparatus by means of an absolute calibration routine utilizing a reaction where a known amount of gas is produced as well as the evaluation of important parameters influencing the gas evolution rate using different substances. It can be shown that the apparatus is capable of measuring absolute gas volumes as low as 6 mL with an acceptable error of about 17% as determined from the reaction of Mg with demineralized water. 相似文献
119.
In this work, a new procedure for the enrichment of the trace amount of Cu2+, Ni2+, Co2+, Pb2+, Fe2+, and Zn2+ ions based on the utilization of multiwalled carbon nanotubes (MWCNT) modified with 2-(2-hydroxy-5-nitrophenyl)-4,5-diphenyl imidazole as chelating agent prior to their determination by flame atomic absorption spectrometry has been described. The influence of effective parameters including pH, amount of ligand and MWCNT, composition of eluent, and coexisting ions on recoveries of understudy metal ions was examined. At the optimum pH of 5.0, all metal ions were quantitatively sorbed onto the proposed solid phase and completely desorbed with 8?mL of 5.0?mol?L?1 HNO3. The detection limit of Cu2+, Co2+, Ni2+, Pb2+, Fe2+, and Zn2+ ions was 1.7, 2.4, 2.3, 2.9, 2.8, and 1.4?µg?L?1, while the preconcentration factor was 63 for Cu2+ and 94 for the other metal ions and relative standard deviations between 1.8 less than 3.0%. The proposed procedure was applied for the analysis of various samples. 相似文献
120.
Synthesis of novel benzo[d]imidazolyldihydrospiro[indoline-3,1′-isoindole]-2,4′,7′-triones has been described. The key intermediate 2-[(2-sulfanyl-1H-benzo[d]imidazol-5-yl)amino]acetic acid is obtained by reacting 5-amino-2-mercapto benzimidazole and chloroacetic acid. The three-component reaction of 2-[(2-sulfanyl-1H-benzo[d]imidazol-5-yl)amino]acetic acid with isatin and 1,4-benzoquinone in the presence of 10 mol% of L-proline at ambient temperature afforded 2′-(2-mercapto-1H-benzo [d] imidazol-5-yl)-3′,3a′-dihydrospiro[indoline-3,1′-isoindole]-2,4′,7′(2′H,7a′H)-triones. All the synthesized compounds were evaluated for in vitro anti-inflammatory activity. 相似文献