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41.
文章主要介绍一种延期精度高的工业雷管用点火药的设计研究,并与国内普遍使用的工业雷管用点火药进行了比较,设计主要包括提高发火可靠性、提高抗水性能、装配等关键技术的解决方法,从而提高雷管在爆破工程中的延期精度,并降低爆破成本。符合《民用爆炸物品行业技术进步的指导意见》(工信部安[2010]227号)精神的要求。 相似文献
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Shanshan Guo Binhui Chen Donghong Zhao Wenteng Chen Guolin Zhang 《Advanced Synthesis \u0026amp; Catalysis》2016,358(19):3010-3014
A manganese(II) acetate‐catalyzed domino reaction of vinyl azides and 4‐hydroxycoumarin has been developed for the synthesis of polyfunctionalized spirofuranone‐lactams. A wide range of vinyl azides are capable of providing the desired spirofuranone‐lactams in good to excellent yields. The reaction was achieved via thermal decomposition of vinyl azides to 2H‐azirines, followed by an intramolecular nucleophilic attack and stereoselective cyclization. The mild reaction conditions and easy operation make this reaction advantageous for the synthesis of spirofuranone‐lactams.
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Huang Da Song Yi Xiang Ma Guo Wei Pei Xiang Jun Huang Run Qiu 《Bulletin of Engineering Geology and the Environment》2019,78(7):4713-4729
Bulletin of Engineering Geology and the Environment - Ring-shear experiments are commonly conducted to analyze the kinematic mechanisms of landslides triggered by earthquakes, particularly for... 相似文献
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Municipal solid waste incineration(MSWI) fly ash is a by-product from municipal waste incineration.According to incomplete statistics, each year more than one million tons MSWI fly ash was produced in China. Owing to high heavy elements content, widely used disposal methods of landfill are not suitable for MSWI fly ash treatment. In this study, by using MSWI fly ash as raw materials, glassceramics was synthesized for the solidification of heavy metals and waste recycle. Process parameters, including composition, heat treatment temperature and time, were studied and optimized. Under optimizing conditions, the product has good properties of density of 3.42 g·cm~(-3) and Vickers hardness of 6.91 GPa. Moreover, the leaching concentration of heavy metal elements meets allowable values of toxicity characteristic leaching procedure(TCLP).This study offers an alternative for MSWI fly ash recycle. 相似文献
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Zipeng Gong Ying Chen Ruijie Zhang Yinghan Wang Yan Guo Qing Yang Haixian Zhang Yu Dong Xiaogang Weng Shuangrong Gao Xiaoxin Zhu 《International journal of molecular sciences》2014,15(1):456-467
In the present study, post inflammation irritable bowel syndrome (PI-IBS) rats were firstly established by intracolonic instillation of acetic acid with restraint stress. Then the pharmacokinetics of berberine in the rat plasma were compared after oral administration of berberine hydrochloride (25 mg/kg) to normal rats and PI-IBS rats. Quantification of berberine in the rat plasma was achieved by using a sensitive and rapid UPLC-MS/MS method. Plasma samples were collected at 15 different points in time and the pharmacokinetic parameters were analyzed by WinNonlin software. Compared with the normal group, area under the plasma concentration vs. time curve from zero to last sampling time (AUC0–t) and total body clearance (CL/F) in the model group significantly increased or decreased, (2039.49 ± 492.24 vs. 2763.43 ± 203.14; 4999.34 ± 1198.79 vs. 3270.57 ± 58.32) respectively. The results indicated that the pharmacokinetic process of berberine could be altered in PI-IBS pathological conditions. 相似文献
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Lin Qiu Yanhua Bi Cheli Wang Jingyan Li Peilin Guo Jinchen Li Weijiang He Jianhao Wang Pengju Jiang 《International journal of molecular sciences》2014,15(2):1804-1811
In this report, fluorescence detection coupled capillary electrophoresis (CE-FL) was used to detect Protein A. Antibody was first labeled with Cy5 and then mixed with quantum dots (QDs) to form QDs-antibody bioprobe. Further, we observed fluorescence resonance energy transfer (FRET) from QDs donor to Cy5 acceptor. The bioprobe was formed and brought QDs and Cy5 close enough to allow FRET to occur. After adding protein A, the FRET system was broken and caused the FRET signal to decrease. Thus, a new method for the determination of protein A was proposed based on the FRET signal changes. This study provides a new trail of thought for the detection of protein. 相似文献
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工程施工中的流水施工技术源于工业生产中的“流水线作业法”,是一种理想的组织产品生产方法,其将工程项目建造过程分解成为若干个施工过程,并按照一定的顺序依次进行各个阶段的施工,从而完成整个施工工程,对工程施工的质量保证起到了重要的意义。 相似文献