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101.
Six inorganic compounds, i.e., Na2CO3, NaOH, NaCl, Na2SiO3, TiO2 and HZSM-5, have been investigated with regard to their catalytic effects on pyrolysis of three biomass species, i.e., pine wood, cotton stalk and fir wood by thermal analysis experiments. The results show that Na2CO3, NaOH, Na2SiO3 and NaCl made devolatilization occur at lower temperature regions in the pyrolysis of the three kinds of biomass, whereas TiO2 and HZSM-5 made that occur at higher temperature regions in the pyrolysis of cotton stalk and had no obvious effects on pyrolysis temperatures of pine wood and fir wood. The basic catalysts NaOH, Na2CO3 and Na2SiO3 decreased the maximum weight loss rates while NaCl and HZSM-5 increased them and TiO2 had no obvious effects on them. The four sodium compounds made pyrolysis of the three kinds of biomass more exothermic, which might be due to more char formation, whereas TiO2 and HZSM-5 had minor effects on reaction heat. The catalytic effects in all aspects were roughly correlated with one another and their relationship with the basicity and acidity of the catalysts were preliminarily described and analyzed. 相似文献
102.
103.
某些氨基取代环戊二烯配合物催化1,5-己二烯的高选择性环化 总被引:2,自引:0,他引:2
We have interested for some years in studying organic reactions catalyzed by (RCp)2TiCl2/i-C3H7MgX, specially isomerization of non-conjugated dienes[1,2]. Titanocene complexes are also effective for some cyclization reactions[3]. In the case of isomerization of 1,5-hexadiene (HD), such catalysts usually result in a mixture of 1,4-hexadiene, 1,3-hexadiene, 2,4-hexadiene, methylenecyclopentane and methylcyclopentene. Our previous results showed that the product distribution largely depends on the characteristics of the substituents on cyclopentadienyl (Cp) ring[2]. 相似文献
104.
Zhengwei Du Jeffrey S. Fu Ke Gong 《International Journal of Infrared and Millimeter Waves》1999,20(2):351-356
In this paper, asymmetrical coplanar striplines (ACPS) with multilayer substrates and overlays are analyzed using conformal mapping method. Analytic closed-form expressions for the basic parameters are obtained. The analyses are useful for monolithic microwave integrated circuits and integrated optical application. 相似文献
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106.
Dr. Liya Qi Zhengwei Wu Binglu Zhao Bojun Liu Wenyun Wang Dr. Hao Pei Yuqing Dong Dr. Shijun Zhang Dr. Zhengjin Yang Dr. Liangliang Qu Dr. Weixia Zhang 《Chemistry (Weinheim an der Bergstrasse, Germany)》2020,26(19):4193-4203
Lithium (Li) metal is considered as the most promising anode material for rechargeable high-energy batteries. Nevertheless, the practical implement of Li anodes is significantly hindered by the growth of Li dendrites, which can cause severe safety issues. To inhibit the formation of Li dendrites, coating an artificial layer on the Li metal anode has been shown to be a facile and effective approach. This review mainly focuses on recent advances in artificial layers for stable Li metal anodes. It summarizes the progress in this area and discusses the different types of artificial layers according to their mechanisms for Li dendrite inhibition, including regulation of uniform deposition of Li metal and suppression of Li dendrite growth. By doing this, it is hoped that this contribution will provide instructional guidance for the future design of new artificial layers. 相似文献
107.
Bo Tang Shoulong Ren Zhenyu Zhang Weiqiu Huang Zhengwei Wang Yuanzhe Dai 《无机化学与普通化学杂志》2020,646(7):359-367
Photocatalysis attracts increasing attention because of the deteriorating environment pollution. Metal organic frameworks (MOFs) is deemed as one kind of promising modifiers to improve the photocatalytic performance of traditional semiconductors by their large BET areas. In this study, reduced graphene oxide (RGO) and Cu-BTC are utilized to decorate TiO2 to enhance the corresponding photoactivity. Morphology of the as-prepared composite is detected by SEM and XRD curve, while the UV- and visible-light activities are estimated by the decomposition of various dyes. The specific functions of Cu-BTC and RGO are revealed by analysing the adsorption capacity, lifetime of the photoinduced electrons and the EPR profiles. The resulting Cu-BTC-RGO/TiO2 samples display outstanding photocatalytic properties, which are much better than that of the pure TiO2 and RGO/TiO2 samples because of the synergy between these components. Lastly, the recycle using stability and the influence from the preparation process of the composite photocatalysts are discussed. 相似文献
108.
Tao Yu Zhengwei Ding Wenzheng Nie Dr. Jiao Jiao Prof. Dr. Hailong Zhang Prof. Dr. Qian Zhang Chao Xue Prof. Xinhua Duan Prof. Dr. Yoichi M. A. Yamada Prof. Dr. Pengfei Li 《Chemistry (Weinheim an der Bergstrasse, Germany)》2020,26(26):5729-5747
The increased demand for more efficient, safe, and green production in fine chemical and pharmaceutical industry calls for the development of continuous-flow manufacturing, and for chiral chemicals in particular, enantioselective catalytic processes. In recent years, this emerging direction has received considerable attention and has seen rapid progress. In most cases, catalytic enantioselective flow processes using homogeneous, heterogeneous, or enzymatic catalysts have shown significant advantages over the conventional batch mode, such as shortened reaction times, lower catalysts loadings, and higher selectivities in addition to the normal merits of non-enantioselective flow operations. In this Minireview, the advancements, key strategies, methods, and technologies developed the last six years as well as remaining challenges are summarized. 相似文献
109.
Ma Zhengwei Sui Weihong Liu Jing Wang Wenjun Li Songmei Chen Tiantian Yang Guanglei Zhu Kaixing Li Zhenjiang 《Journal of Solid State Electrochemistry》2022,26(4):973-984
Journal of Solid State Electrochemistry - Lithium-sulfur batteries are of significant roles in the next-generation energy storage devices due to the high theoretical capacity and energy density.... 相似文献
110.