检索结果-南通市图书馆

Strategies for Selection of intermediate Trader for Feed and Veterinary Drug Enterprises

在线全文

学校读者我要写书评

暂无评论

Asian Agricultural Research 2015年第4期7卷 10-12页

作者： Zhongming SHEN Department of Business and Trade Southwest University Rongchang Campus

intermediate trader plays an extremely important role in marketing,production,and operating of China's feed and veterinary drug enterprises. China's feed and veterinary drug enterprises should select suitable intermediate traders using such strategies as sincerity,operating capacity,economic strength,business scope,operating place,and excellent cooperation attitude,to promote stable and sustainable development of feed and veterinary drug enterprises.

关键词： Feed and veterinary drug enterprises intermediate

Rational Manipulation of intermediates on Copper for CO_(2)Electroreduction Toward Multicarbon Products

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Transactions of Tianjin University 2022年第4期28卷 265-291页

作者： Guangyi Jiang Daliang Han Zishan Han Jiachen Gao Xinyu Wang Zhe Weng Quan-Hong Yang Nanoyang Group State Key Laboratory of Chemical EngineeringSchool of Chemical Engineering and TechnologyTianjin UniversityTianjin 300072China Haihe Laboratory of Sustainable Chemical Transformations Tianjin 300192China Collaborative Innovation Center of Chemical Science and Engineering(Tianjin) Tianjin 300072China Joint School of National University of Singapore and Tianjin University International Campus of Tianjin UniversityBinhai New CityFuzhou 350207China

Excess greenhouse gas emissions,primarily carbon dioxide(CO_(2)),have caused major environmental concerns *** electroreduction of CO_(2)into valuable chemicals using renewable energy is an ecofriendly approach to achieve carbon *** this regard,copper(Cu)has attracted considerable attention as the only known metallic catalyst available for converting CO_(2)to high-value multicarbon(C_(2+))*** production of C_(2+)involves complicated C-C coupling steps and thus imposes high demands on intermediate *** this review,we discuss multiple strategies for modulating intermediates to facilitate C_(2+)formation on Cu-based ***,several sophisticated in situ characterization techniques are outlined for elucidating the mechanism of C-C ***,the challenges and future directions of CO_(2)electroreduction to C_(2+)are envisioned.

关键词： CO_(2)electroreduction Copper-based electrocatalysts Multicarbon products intermediate C-C coupling

intermediates transformation for efficient perovskite solar cells

在线全文

学校读者我要写书评

暂无评论

Journal of Energy Chemistry 2021年第1期30卷 102-114,I0004页

作者： Zhizai Li Yi Sun Huanhuan Yao Jing Zhao Qian Wang Liming Ding Zhiwen Jin School of Physical Science and Technology&Key Laboratory for Magnetism and Magnetic Materials of MoE&Key Laboratory of Special Function Materials and Structure Design MoE&National&Local Joint Engineering Laboratory for Optical Conversion Malerials and TechnologyLanzhou UniversiyLanzhou 730000 GansuChina School of Physics Changhi UnversityChornghi 830100 Xinjiang Uygur Autonomous RegionChina Center for Excllence in Nanoscience(CAS) Key Laboratony of Nonosystem anp Hierarchical Fabrication(CAS)Nationol Center for Nanoscience and TechnologyBeijing 100190China

Perovskite materials have made a great progress in terms of the power conversion efficiency(PCE), rising from 3.8% to 25.2%. To obtain pinhole-free, superior crystal, and high-quality perovskite films with less defect, intermediates transformation is important, which has been clearly studied and widely *** this review, we systematically summarize the commonly formed intermediates and detailedly analyze their mechanisms from five aspects:(1) Solvent-induced intermediate;(2) HI-induced intermediate;(3)CH3NH2-induced intermediate;(4) MAAc-induced intermediate;(5) other intermediates. Finally, we also provide some prospects on high-quality perovskite fabrication based on using intermediates prudently.

关键词： intermediate Formation energy Crystalline dynamics Solubility Nucleation sites

通过二氧化硅纳米包覆捕捉监测纳米晶体快速转变过程的中间体

在线全文

学校读者我要写书评

暂无评论

Science China Materials 2022年第7期65卷 1963-1970页

作者：王若徐王倩郭慧颖陈虹宇 Institute of Advanced Synthesis(IAS) School of Chemistry and Molecular EngineeringJiangsu National Synergetic Innovation Centre for Advanced MaterialsNanjing Tech UniversityNanjing 211816China School of Science Westlake UniversityHangzhou 310024China Institute of Natural Sciences Westlake Institute for Advanced StudyHangzhou 310024China

在透射电子显微镜(TEM)表征中,微包覆是一种重要的工具,以保存纳米颗粒的形貌不受聚集、风化和高能电子束的破坏.传统上,微包覆只能用来捕捉最终产物.本研究探索实时微包覆技术的极限,以捕捉短纳米颗粒生长过程中转瞬即逝的中间体.本文... 详细信息

在透射电子显微镜(TEM)表征中,微包覆是一种重要的工具,以保存纳米颗粒的形貌不受聚集、风化和高能电子束的破坏.传统上,微包覆只能用来捕捉最终产物.本研究探索实时微包覆技术的极限,以捕捉短纳米颗粒生长过程中转瞬即逝的中间体.本文通过溶质诱导相分离(SIPS)体系生成了水溶性盐的纳米晶体.利用改进的Stober微包覆技术捕捉了该过程中不同时间点上的一系列中间体.并且将它们按照时间顺序排列,还原出该水溶性盐纳米晶体的生长过程.除此以外,本研究还捕捉到了一例从盐纳米晶体到液滴的转变过程,展示出了SIPS体系可能存在一种与之前推测不同的变化途径.该微包覆技术可便捷地捕捉纳米颗粒生长中不同阶段的a快照o以便进行TEM表征,为纳米级生长机理研究提供了更多关键信息.

关键词： encapsulation hollow nanostructures intermediate salt nanocrystal nanoscale droplet kosmotrope

Disassembly intermediates of RbsD protein remain oligomeric despite the loss of an intact secondary structure

在线全文

学校读者我要写书评

暂无评论

Science China(Life Sciences) 2009年第11期52卷 997-1002页

作者： FENG YongJun1, ZHANG Meng2, HU MingXi1, ZHENG Jie1, JIAO WangWang2 & CHANG ZengYi2 1 School of Life Science, Beijing Institute of Technology, Beijing 100081, China 2 School of Life Sciences, National Laboratory of Protein Engineering and Plant Genetic Engineering, Center for Protein Science, Peking University, Beijing 100871, China School of Life Science Beijing Institute of Technology Beijing China School of Life Sciences National Laboratory of Protein Engineering and Plant Genetic Engineering Center for Protein Science Peking University Beijing China

Many proteins exist as homo-oligomers in living organisms wherein the change of oligomeric status apparently serves as an effective means for modulating their biological activities. We have previously reported that the homo-decameric RbsD from Escherichia coli undergoes stepwise disassembly and non-stepwise reassembly. Here the structural status of the urea-induced RbsD disassembly intermediates was examined, mainly using urea-containing polyacrylamide gel electrophoresis and chemical cross-linking. Such intermediates were found to remain oligomeric while losing their intact secondary structures. Such disassembly intermediates were able to effectively refold when the concentration of the urea denaturant was reduced to a lower level, or to refold/reassemble into the native decamers when urea was completely removed, as detected by non-denaturing polyacrylamide gel electrophoresis. These novel observations strongly suggest that the assembly of oligomeric proteins may occur before the completion of subunit folding.

关键词： RbsD oligomeric protein oligomeric intermediate refolding reassembly

Mechanistic Insight into Ethanol Dehydration over SAPO-34 Zeolite by Solid-state NMR Spectroscopy

在线全文

学校读者我要写书评

暂无评论

Chemical Research in Chinese Universities 2022年第1期38卷 155-160页

作者： ZHOU Xue WANG Chao CHU Yueying WANG Qiang XU Jun DENG Feng National Centre for Magnetic Resonance in Wuhan State Key Laboratory of Magnetic Resonance and Atomic and Molecular PhysicsWuhan Institute of Physics and MathematicsInnovation Academy for Precision Measurement Science and TechnologyChinese Academy of SciencesWuhan 430071P.R.China

The reaction mechanism of ethanol dehydration over SAPO-34 zeolite is investigated by using solid-state NMR spectroscopy. SAPO-34 zeolites with different Si contents are prepared and their acidities are characterized by NMR experiments. The higher content of stronger Brønsted acid sites is correlated to the higher Si content. The adsorption of ethanol on the Brønsted acid sites in SAPO-34 leads to the formation of frustrated Lewis pairs(FLPs). Surface ethoxy species is observed by the dehydration of the FLP sites at room temperature, which can be further converted into ethene products. The decomposing of diethyl ether over Brønsted acid sites is responsible for the formation of ethoxy species at higher reaction temperatures. Triethyloxonium ions are formed in the reaction. A plausible reaction mechanism is proposed for the dehydration of ethanol over SAPO-34.

关键词： Ethanol dehydration SAPO-34 intermediate Reaction mechanism Solid-state NMR

Recent advances on surface metal hydrides studied by solid-state nuclear magnetic resonance spectroscopy

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Magnetic Resonance Letters 2023年第1期3卷 31-42,I0003页

作者： Pan Gao Guangjin Hou State Key Laboratory of Catalysis Dalian National Laboratory for Clean Energy2011-Collaborative Innovation Center of Chemistry for Energy MaterialsDalian Institute of Chemical PhysicsChinese Academy of Sciences457 Zhongshan RoadDalian116023China

Metal hydrides (MeH) on solid surfaces, i.e., surface MeH, are ubiquitous but criticalspecies in heterogeneous catalysis, and their intermediate roles have been proposed innumerous reactions such as (de)hydrogenation and alkanes activation, etc., however, thedetailed spectroscopic characterizations remain challenging. Solid-state nuclear magnetic resonance (ssNMR) spectroscopy has become a powerful tool in surface studies, asit provides access to local structural characterizations at atomic level from multipleviews, with comprehensive information on chemical bonding and spatial structures. Inthis review, we summarized and discussed the latest research developments on thesuccessful application of ssNMR to characterize surface MeH species on solid catalystsincluding supported single-site heterogeneous catalysts, bulk metal oxides and metalmodified zeolites. We also discussed the opportunities and challenges in this field, aswell as the potential application/development of state-of-the-art ssNMR technologies toenable further exploration of metal hydrides in heterogeneous catalysis.

关键词： Metal hydrides Surface chemistry intermediate Solid-state NMR Heterogeneous catalysis