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51.
Hao Sun Cunlu Dong Aijun Huang Prof. Haijuan Zhan Dr. Gang Wang Prof. Wanyi Liu Prof. Baojun Ma Prof. Wei Wang 《Chemistry (Weinheim an der Bergstrasse, Germany)》2022,28(28):e202200019
Transition metal Fe, Co, Ni and Cu doped strontium titanate-rich SrTiO3@TiO2 (STO@T) materials were prepared by hydrothermal method. The prepared doped materials exhibit better photocatalytic CO2 reduction to CH4 ability under visible light conditions. Among them, Fe-doped and undoped SrTiO3@TiO2 under visible light conditions CO2 reduction products only CO, while M-STO@T (M=Co, Ni, Cu) samples converted CO2 to CH4. The average methane yield of Ni-doped STO@T samples are as high as 73.85 μmol g−1 h−1. The production of methane is mainly due to the increase in the response of the doped samples to visible light. And the increase in the separation rate of photogenerated electrons and holes and the efficiency of electron transport caused by the generation of impurity levels. The impurity level caused by Ti3+ plays an important role in the production of methane by CO2 visible light reduction. Ni doping effectively improves the photocatalytic performance of STO@T and CO2 reduction mechanism were explained. 相似文献
52.
Guo Lan Guan Yali Liu Peng Gao Linghuan Wang Zhifu Huang Shengli Peng Liang Zhao Zhiyu 《Cellulose (London, England)》2022,29(3):1315-1330
Cellulose - Extracellular vesicles are membrane-packed entities that are involved in various physiological and pathological processes. Recently, the role of exosomes and microvesicles in... 相似文献
53.
针对传统暂堵酸化用暂堵剂颗粒耐酸性差、降解性差和除堵工艺复杂等问题,本研究通过水溶液自由基聚合法制备了一种新型的自降解暂堵剂CQZDJ。考察了单体加量、交联剂加量、引发剂加量对CQZDJ凝胶强度和降解性的影响;通过FT-IR、TGA、SEM对其结构进行表征;并对其降解机理进行了探讨;最后在长8区块的环平81-8实验井进行了现场实践。结果表明:CQZDJ凝胶强度及降解时间与单体加量、交联剂加量、引发剂加量成正比关系,且降解时间可控;降解性实验表明CQZDJ在(1%~10%)HCl溶液、水、(2%~10%)NaCl溶液中均可在4 d内完全降解,具备良好的降解性能,对地层伤害小;SEM照片显示CQZDJ的降解过程是从初始三维网状结构逐渐崩解为层状结构,最终降解为无规则线性小分子链的过程;暂堵后现场流压上升6.3 MPa,日产油由3.87 t/d增产至5.22 t/d,实现了储层的有效改造,增产效果显著。
相似文献
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Dr. Hongying Tang Jian Gao Prof. Yidong Wang Prof. Nanwen Li Dr. Kang Geng 《Chemistry (Weinheim an der Bergstrasse, Germany)》2022,28(70):e202202064
Great efforts have been conducted to develop high temperature proton exchange membrane fuel cell (HT-PEMFC) due to its features of enhanced electrocatalyst reactivity, simplified hydrothermal management system and high CO tolerance of catalysts, and remarkable progress has been achieved. However, the easy leaching of phosphoric acid (PA) from the membranes during operation limits its commercial scale-up in complicated environments. This concept here mainly focuses on the recent developments for mitigation of PA loss in PEMs. The probable mechanisms of PA loss are proposed. The approaches to improve PA retention for example via introduction of phosphonic acid by covalent bond, using ion-pairs interaction and siphoning effect, and blending with inorganic nanoparticles are described in detail. Among these strategies, the siphoning effect from the intrinsic microporous PEMs is the most efficient and enables the cell to operate flexibly within a broad temperature range. Therefore, this concept may provide new ideas for the scientists to retain PA, to improve the cell performance and expand the potential applications of PA doped PEMs at elevated humidity and wide temperature range. 相似文献
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Yang Gang Wang Yanhui Yang Xueying Pan Yuelong Liu Yu Cheng Jianfeng Jiang Qiao Tuo Xianguo 《Journal of Radioanalytical and Nuclear Chemistry》2022,331(5):2135-2145
Journal of Radioanalytical and Nuclear Chemistry - The preparation of C30 concrete for a cavernous waste repository under construction in China and its Cs(I) adsorption performance were... 相似文献
59.
Landgrave-Barbosa Fernando Marmolejo-Valencia Andrés F. Baray-Calderón Alejandro Hu Hailin Aguilar-Cordero Julio César Amador-Bedolla Carlos Ugalde-Saldivar Víctor M. 《Journal of Solid State Electrochemistry》2022,26(3):649-661
Journal of Solid State Electrochemistry - A study of poly(3-hexylthiophene) (P3HT) thin films by spin-coating process, deposited on conducting glass substrates of fluorine-doped tin oxide (FTO), is... 相似文献
60.
Designs, Codes and Cryptography - It has been shown that all the known binary Golay complementary sequences of length $$2^m$$ can be obtained by a single binary Golay complementary array of... 相似文献