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991.
992.
近年来,大量化石燃料的使用改变了全球气候,加剧了温室效应并且产生了严重的热污染.能源枯竭和环境污染问题迫在眉睫,为实现生态环境的可持续发展,人们研究和开发了各种新型的储能材料和器件.超级电容器是最近几年发展迅速的一种新型储能装置,典型特点是储能和快速充放电.因为生物质绿色无污染、资源丰富和可再生,另外,生物质氮自掺杂炭材料因为孔隙发达、孔隙可调、耐酸碱、比表面积大,故可作为制备电极材料碳源的最优选择.本文分别以石榴籽和化妆棉两种生物质作为碳源,利用高温热解法来制备生物质氮自掺杂炭材料电极,并测其电化学性能.经过电化学测试得出,在1 A/g的电流密度下,石榴籽与KOH的质量比为3:1时比电容最大,约为295 F·g-1,同样电流密度下,化妆棉与KOH质量比为3:1时比电容最大,约为225 F·g-1. 相似文献
993.
Ma Yujie Su Peng Ge Yizhao Wang Fangwai Xue Ruixue Wang Zijun Li Yongsheng 《Catalysis Letters》2022,152(10):2993-3003
Catalysis Letters - In this paper, the LaAlO3 perovskite with large specific surface area and abundant surface oxygen vacancies is prepared by the hard template method, on which Ni metal... 相似文献
994.
Song Dongdong He Chuang Zhang Gang Wang Yanlin Liang Zuoqin Jiang Zicheng Ma Su 《Journal of Inorganic and Organometallic Polymers and Materials》2022,32(5):1902-1912
Journal of Inorganic and Organometallic Polymers and Materials - Currently, the issue of natural flammability of unsaturated polyester resin (UPR) severely restrains its application. In this study,... 相似文献
995.
Jianhua Wen Tao Zeng Xiaotong Pan Zhijuan Zhong Siwen Yu Su Cheng 《International Journal of Applied Ceramic Technology》2022,19(6):3007-3016
3D-printed SiC ceramics were prepared by direct ink writing and solid-phase sintering. The effects of sintering temperature, solid loading, and carbon additive on microstructures and mechanical properties of 3D-printed SiC parts were investigated. It was found that the sintering temperature affected the evolution of the microstructure and mechanical properties of the sintered SiC parts. A high solid loading promoted the densification and mechanical properties of the sintered SiC parts. However, the solid loading exceeded 40 vol.%, which decreased the density and mechanical properties of the samples. The carbon additives could improve the densification of the SiC parts and enhance their mechanical properties. When the sucrose content increased from 0 to 8 wt.%, the open porosity of the SiC part decreased from 26.12% to 3.15%, whereas the flexural strength increased 2.19 times. Using the optimized components and process parameters, the high-performance 3D-printed SiC parts were achieved. 相似文献
996.
Xue Zhang Jin Du Guosheng Su Peirong Zhang Yujing Sun Chongyan Zhang Xiangmin Kong 《International Journal of Applied Ceramic Technology》2022,19(3):1354-1366
Mo2NiB2 is a kind of cermet with excellent mechanical properties, stable chemical properties, and excellent corrosion resistance and is often used in wear-resistant application fields, such as injection molding machine parts, can making tools and hot copper extruding dies. The brittleness of Mo2NiB2-based cermets limits their wide application. Mo2NiB2-based cermets were prepared by the vacuum sintering method, the effect of SiC whiskers (SiCw) on the microstructure and mechanical properties of cermets was investigated, and the toughening mechanism of SiCw on cermets was further discussed. The results indicate that with increasing SiCw content, the indentation fracture toughness (KIC), transverse fracture strength (TRS), and Vickers hardness (HV) of the cermets first increase and then decrease. The HV, TRS, and indentation fracture toughness of Mo2NiB2-based cermets with 0.5 wt% SiCw are 1 113 HV, 1 620 MPa, and 27.97 MPa·m1/2, respectively, which are 16.8%, 22.7%, and 25% higher than those without SiCw. In the sliding friction tests, Mo2NiB2-based cermets with 0.5 wt% SiCw have the smallest friction coefficient, low wear rate, and high wear resistance. SEM observation and analysis of the crack path and fracture surface showed that the toughening mechanism is whisker bridging, crack deflection, microcrack toughening, and whisker pull-out. The results indicate that the addition of 0.5 wt% SiCw can effectively improve the mechanical properties of Mo2NiB2-based cermets and further expand the application space of Mo2NiB2-based cermets. 相似文献
997.
Silicon - 2D global transient numerical model based on a new large-size ALD-G7 (G7) crystalline silicon ingot furnace is established and experimentally verified. A new pyramid-shaped bottom grille... 相似文献
998.
Silicon - 3D global simulations were performed to investigate the gas flow and impurities transport in casting silicon furnace under the influence of a unique designed spray-type gas guidance... 相似文献
999.
提出了在As-NaOH-ClO体系脱砷的方法,并以含砷镍烟灰为原料,系统研究了该体系下的脱砷效果。结果表明:在液固比L/S=10、NaClO浓度4.1%、NaOH浓度3%、反应温度50℃、反应时间1h的最优条件下,砷脱除率达到75%以上,镍损失率小于0.03%,可实现砷的无害化处理和金属镍的回收。 相似文献
1000.
Siyi Ma Su Ruiming Wang Kaining Yang Yuping Qu Yingdong Li Rongde 《Russian Journal of Non-Ferrous Metals》2021,62(1):89-96
Russian Journal of Non-Ferrous Metals - The 7075 aluminum alloy was subjected to deep cryogenic treatment (DCT) at –196°C with liquid nitrogen for different hours. The wear and corrosion... 相似文献