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991.
�� ����������������ʤ���� ������ �죬���¶������ع� 《核聚变与等离子体物理》2015,35(4):373-378
Different ratios of methane/air in the low power arc discharges assisted methane combustion were studied at atmospheric pressure. Plasma emission spectroscopy was recorded by an optical emission spectrometer. The possible physical and chemical reaction process and mechanisms were discussed. With a plasma in the on or off state, the physical appearances of the methane combustion flame were observed and compared, the temperature of the flame in the main combustion zone was investigated. The gas compositions of CH4, CO and O2 were analyzed by the gas chromatography and flue gas analyzer. The results showed that when plasma was in the on state, the temperature of flame increased and the combustion efficiency enhanced in stable combustion due to decrease of CH4, CO and O2; the combustion enhancement was more obvious at low ratio of methane/air; the rich combustion limits in terms of the ratio of methane/air was extended from 16% to 21%. 相似文献
992.
993.
In this paper,we present a simple method by combining surface wrinkling and template replication to create a series of hierarchical structures on polydimethylsiloxane(PDMS) elastomer.The primary stable lined patterns are formed by duplicating commercialized compact disk and digital versatile disk with PDMS.The secondary microscale patterns are from surface wrinkling,which is elicited by oxygen plasma(OP) treatment of the prestrained PDMS stamp followed with the prestrain release.By systematically varying the OP exposure duration,the prestrain,and the angle(θ) between the primary pattern orientation and the prestrain direction,we obtain highly ordered well-organized composite patterns from different patterning techniques and with different length scales and mechanical stabilities. 相似文献
994.
Hongming He Qian‐Qian Zhu Chuanqi Zhang Ying Yan Jing Yuan Jing Chen Cheng‐Peng Li Miao Du 《化学:亚洲杂志》2019,14(7):917-917
995.
996.
Zhu Hong Zeng Xiangbing Han Tianli Li Xuexue Zhu Shuguang Sun Bai Zhou Ping Liu Jinyun 《Journal of Solid State Electrochemistry》2019,23(7):2173-2180
Journal of Solid State Electrochemistry - Since conventional graphite-based anode possesses a low capacity, seeking for high-capacity anode candidates becomes significant for constructing emerging... 相似文献
997.
Numerical preference relations (NPRs) consisting of numerical judgments can be considered as a general form of the existing preference relations, such as multiplicative preference relations (MPRs), fuzzy preference relations (FPRs), interval MPRs (IV-MPRs) and interval FPRs (IV-FPRs). On the basis of NPRs, we develop a stochastic preference analysis (SPA) method to aid the decision makers (DMs) in decision making. The numerical judgments in NPRs can also be characterized by different probability distributions in accordance with practice. By exploring the judgment space of NPRs, SPA produces several outcomes including the rank acceptability index, the expected priority vector, the expected rank and the confidence factor. The outcomes are obtained by Monte Carlo simulation with at least 95% confidence degree. Based on the outcomes, the DMs can choose some of them which they find most useful to make reliable decisions. 相似文献
998.
Herein we summarized some clean preparation examples to emphasize the concept of dual roles design (or named as “two birds one stone strategy”) in green and sustainable chemistry. In those examples, the reactants and/or solvent play dual roles rendering a cleaner organic preparation process. Consequently, both the chemical waste and manufacturing cost could be reduced. 相似文献
999.
1000.
Two new compounds, 19-hydroxy-melodinine K (1) and melodiside (2), and 25 known compounds were isolated from leaves and twigs of Melodinus suaveolens. Their structures were elucidated based on 1- and 2-D NMR, FTIR, UV and MS spectroscopic data. 19-hydroxy-melodinine K showed cytotoxic activity against MDA-MB-231 breast, BCG-823 gastric, SW480 colon and Hela cancer cells. 相似文献