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B. P. Aduev D. R. Nurmukhametov A. A. Zvekov N. V. Nelyubina 《Combustion, Explosion, and Shock Waves》2014,50(5):578-581
Pulsed laser initiation is used to experimentally investigate the thresholds of explosive decomposition of PETN-based compounds with aluminum nanoparticle inclusions depending on the core-shell (Al/Al2O3) mass ratio in the particle. It is found that, with decreasing mass fraction of Al from 74 to 13%, the explosive decomposition threshold increases by a factor of 12.5. Light absorption efficiency calculations for the core-shell system performed by the Aden-Kerker method for Al/Al2O3 inclusions in PETN show that this efficiency decreases with decreasing mass of metal in the particle. The experimental and theoretical results can be regarded as an additional confirmation of the hot-spot concept of laser initiation of PETN containing nanoscale inclusions of metals. 相似文献
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Kaizhao Wang Jin Hu Tianyou Chen Weijun Zhang Hongtao Fan Yongjin Feng Ziqiang Zhao Kaijun Wang 《大分子材料与工程》2021,306(12):2100457
A polydimethylsiloxane (PDMS) matrix soft elastic composite material with low-melting-point GaInSnPbBi high-entropy alloy (LHEA) inclusions is prepared to evaluate its radiation shielding performance. The LHEA is composed of two different three-component eutectic microstructures, which are grown in a mixed manner to form a complex eutectic structure. The inclusions have excellent mechanical properties that matched the deformation of the PDMS matrix. To evaluate the interaction of the shielding material with photons, the Monte Carlo N-Particle Extended and XCOM codes are used to determine the shielding parameters of the LHEA/PDMS composites, such as mass attenuation coefficient, linear attenuation coefficient, half-value layer, tenth value layer, mean free path, and effective atomic number. The composite with 50-vol% LHEA has the best radiation shielding properties, validated by medical X-ray imaging experiments. The excellent shielding properties of the flexible lightweight composites are attributed to the higher mass attenuation coefficient of the LHEA inclusions than that of lead. 相似文献
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以西安钟楼饭店为例,通过对该建筑特征价值、与类似文物建筑的比较,并参考英国遗产评定标准进行评价,得出改革开放30年建设的当代典型建筑是可以进入遗产保护行列的。 相似文献
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Svetlana A. Murzina Polina Yu. Dgebuadze Svetlana N. Pekkoeva Viktor P. Voronin Elena S. Mekhova Nguyen T. H. Thanh 《European Journal of Lipid Science and Technology》2021,123(7):2000321
The sea urchin Diadema setosum is edible and desirable as food by locals in central Vietnam and a promising target for potential fishing. The lipid profiles of the gonads of the sea urchin inhabiting the coastal area in Nha Trang Bay are studied for the first time. The determination of the content of the total lipids (TL), total phospholipids (PL), monoacylglycerols (MAG), diacylglycerols (DAG), triacylglycerols (TAG), cholesterol (Chol), sterol esters, and free fatty acids (FFA) is analyzed by high-performance thin layer chromatography (HPTLC); the phosphatidylserine (PS), phosphatidylethanolamine (PE), phosphatidylinositol (PI), phosphatidylcholine (PC), lysophosphatidylcholine (LPC), and sphingomyelin (SM) are determined by high-pressure liquid chromatography (HPLC); and the fatty acid levels of TLs are identified using gas chromatography (GC). Non-polar TAG, FFA, Chol, and DAG dominated. The content of total PL is significant. PC is abundant among PL fractions, followed by PE, PI, and PS. The TLs contain a high proportion of PUFA, mainly due to arachidonic fatty acid and eicosapentanoic fatty acid. The (n−6)/(n−3) ratio is 1.68, and the atherogenic and thrombogenic indexes of D. setosum are 1.13 and 0.73. The results can be used in the development of marine bioprospecting and methodological approaches for the creation of functional substances. 相似文献
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阐述了现有高校老旧建筑改造的方法,指出改造工程目前存在的一些问题,对比分析了内蒙古工业大学原铸工车间和同济大学大礼堂两个典型的成功改造案例,研究得出了高校老旧建筑改造的原则和方法。 相似文献
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