检索结果-南通市图书馆

A vehicle-mounted dual-smog chamber:Characterization and its preliminary application to evolutionary simulation of photochemical processes in a quasi-realistic atmosphere

引用

Journal of Environmental Sciences 2023年第10期132卷 98-108页

作者： Wenlu Wang Yang Xiao Shijie Han Yang Zhang Daocheng Gong Hao Wang Boguang Wang Institute for Environmental and Climate Research Jinan UniversityGuangzhou 511443China Australia-China Centre for Air Quality Science and Management(Guangdong) Guangzhou 511443China Guangdong-Hongkong-Macao Joint laboratory of Collaborative Innovation for Environmental Quality Guangzhou 511443China

Smog chambers are the effective tools for studying formation mechanisms of air *** by traditional smog chambers differ to a large extent from real atmospheric conditions,including light,temperature and atmospheric ***,the existing parameters for mechanism interpretation are derived from the traditional smog *** address the gap between the traditional laboratory simulations and the {1. in the real atmosphere,a vehicle-mounted indoor-outdoor dual-smog chamber(JNUVMDSC)was developed,which can be quickly transferred to the desired sites to simulate quasi-realistic atmosphere simultaneously in both chambers using“local air”.Multiple key parameters of the smog chamber were characterized in the study,demonstrating that JNUVMDSC meets the requirements of general atmospheric chemistry simulation ***,the preliminary results for the photochemical simulations of quasi-realistic atmospheres in Pearl River Delta region and Nanling Mountains are consistent with literature reports on the {1. in this ***-VMDSC provides a convenient and reliable experimental device and means to study the mechanism of atmospheric photochemical reactions to obtain near-real results,and will make a great contribution to the control of composite air pollution.

关键词： Vehicle-mounted dual-smog chamber photochemical processes quasi-realistic atmosphere composite air pollution Pearl River Delta region

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Light-switchable catalytic activity of Cu for oxygen reduction reaction

引用

Frontiers of Materials Science 2020年第4期14卷 481-487页

作者： Yue ZHANG Yihong YU Xiankai FU Zhisen LIU Yinglei LIU Song LI key Lab for Anisotropy and Texture of Materials(MOE) School of Materials Science and EngineeringNortheasterm UniversityShenyang 110819China Liaoning Academy of Analytical Sciences Shenyang 110015China Research Center for Metallic Wires Northeasterm UniversityShenyang 110819China

The surface reactivity of metals is fundamentally dependent on the local electronic structure generally tailored by atomic compositions and configurations during the ***,we demonstrate that Cu,which is inert for oxygen reduction reaction(ORR)due to the fully occupied d-orbital,could be activated by applying a visible-light irradiation at ambient *** ORR current is increased to 3.3 times higher in the potential range between-0.1.and 0.4 V under the light of 400 mW·cm^-2,and the activity enhancement is proportional to the light *** with the help of the first-principle calculation,the remarkably enhanced electrocatalytic activity is expected to stem mainly from the decreased metal-adsorbate binding by *** finding provides an additional degree of freedom for controlling and manipulating the surface reactivity of metal catalysts besides materials strategy.

关键词： photochemistry surface reactivity oxygen adsorption copper

来源：

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

Dancing on Ropes-Enantioselective Functionalization of Preformed Four-Membered Carbocycles

引用

Chinese Journal of Chemistry 2022年第11期40卷 1346-1358,I0002页

作者： Jun Chen Qiang Zhou Huayi Fang Ping Lu Research Center for Molecular Recognition and Synthesis Department of ChemistryFudan University220 Handan LuShanghai 200433China School of Materials Science and Engineering Tianjin Key Lab for Rare Earth Materials and ApplicationsNankai University38 Tongyan RoadTianjin 300350China

Cyclobutane derivatives have been recognized as useful structural motifs in organic synthesis and drug *** the revival of photochemistry,the enantioselective synthesis of cyclobutane derivatives using[2+2]-cycloadditions has garnered numerous *** the other hand,enantioselec-tive functionalization of preformed four-membered carbocycles is emerging as an important complementary approach to access chiral cyclobutane de-rivatives with versatile structural ***,we summarize recent advances in this field from *** avoid undesired C—C bond cleavage driv-en by strain-releasing,it is crucial to choose compatible methods for enantioselective functionalization and meanwhile preserving intact four-membered ring *** by calculated hydrogenation enthalpies,which are used to evaluate the strain energy of indicated C—C bond,a clear picture of the developed methodologies on functionalization of four-membered carbocycles combining the strain energy and enhanced reactivity is presented.

关键词： Enantioselective functionalization Strained molecules Density functional calculations Strain-releasing C-H activation

来源：

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

Increasing photosynthetic performance and post-silking N uptake by moderate decreasing leaf source of maize under high planting density

引用

Journal of Integrative Agriculture 2021年第2期20卷 494-510页

作者： CAO Yu-jun WANG Li-chun GU Wan-rong WANG Yong-jun ZHANG Jun-hua College of Agriculture Northeast Agricultural UniversityHarbin 150030P.R.China Institute of Agricultural Resources and Environment Jilin Academy of Agricultural Sciences/State Engineering Laboratory of MaizeNational Development and Reform CommissionChangchun 130033P.R.China

To date,little attention has been paid to the effects of leaf source reduction on photosynthetic matter production,root function and post-silking N uptake characteristics at different planting *** a 2-year field experiment,Xianyu 335,a widely released hybrid in China,was planted at 60 000 plants ha^(–1.)(conventional planting density,CD) and 90 000 plants ha^(–1. (high planting density,HD),*** all the filaments protruded from the ear,at which point the plants were subjected to the removal of 1.2 (T1.,1.3 (T2) and 1.4 (T3) each leaf length per plant,no leaf removal served as the control(CK).We evaluated the leaf source reduction on canopy photosynthetic matter production and N accumulation of different planting *** CD,decreasing leaf source markedly decreased photosynthetic rate (P_(n)),effective quantum yield of photosystem II (ΦPSII) and the maximal efficiency of photosystem II photochemistry (F_(v)/F_(m)) at grain filling stage,reduced post-silking dry matter accumulation,harvest index (HI),and the *** with the CK,the 2-year average yields of T1.T2 and T3 treatments decreased by 35.4,23.8 and 8.3%,***,decreasing leaf source reduced the root bleeding sap intensity,the content of soluble sugar in the bleeding sap,post-silking N uptake,and N accumulation in *** grain N accumulation in T1.T2 and T3 decreased by 26.7,1..5 and 1..8% compared with CK,*** HD,compared to other treatments,excising T3 markedly improved the leaf P_(n),ΦPSII and F_(v)/F_(m) at late-grain filling stage,increased the post-silking dry matter accumulation,HI and the grain *** yield of T3 was 9.2,35.7 and 20.1. higher than that of CK,T1.and T2 on average,*** T3 treatment also increased the root bleeding sap intensity,the content of soluble sugar in the bleeding sap and post-silking N uptake and N accumulation in *** with CK,T1.and T2 treatments,the grain N accumulation in T3 increase

关键词： different planting densities leaf source reduction canopy photosynthetic matter production post-silking N uptake grain N accumulation

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Reactive nitrogen chemistry in aerosol water as a source of sulfate during haze events in China

Reactive nitrogen chemistry in aerosol water as a source of ...

引用

第十三届全国气溶胶会议

作者： Hang Su Yafang Cheng Guangjie Zheng Chao Wei Qing Mu Bo Zheng Zhibin Wang Qiang Zhang Kebin He Gregory Carmichael Ulrich P?schl Institute for Environmental and Climate Research Jinan University Multiphase Chemistry Department Max Planck Institute for Chemistry State key Joint {1. of Environment Simulation and Pollution Control School of EnvironmentTsinghua University College of Engineering University of Iowa Center for Global and Regional Environmental Research University of Iowa

Fine particle pollution associated with winter haze threatens the health of over 400 million people in the North China *** is a major component of fine haze *** sulfate concentrations up to 00 μg m were observed during the January 201. winter haze event in ***-of-the-art air quality models relying on sulfate production mechanisms that require photochemical oxidants, cannot predict these high levels due to the weak photochemistry activity during haze *** find that the missing source of sulfate and particulate matter can be explained by reactive nitrogen chemistry in aerosol *** aerosol water serves as a reactor where the alkaline aerosol components trap SO, which is oxidized by NO to form sulfate, whereby high reaction rates are sustained by the high neutralizing capacity of the atmosphere in northern *** mechanism is self-amplifying because higher aerosol mass concentration corresponds to higher aerosol water content leading to faster sulfate production and more severe haze pollution.

关键词：

来源： cnki会议评论

在线全文

cnki会议

学校读者我要写书评

暂无评论

Synthesis and Magnetic Properties of Prussian Blue Analogue Hollow Microcubes in a Low Temperature Hydrothermal Process

引用

近代物理研究所和兰州重离子加速器实验室年报：英文版 2008年第1期 64-64页

作者： Sun Jianrong Wei Kongfang Zang Hang Yao Cunfeng Shen Tielong Shen Yanbin Ma Yizhun Gou Jie Wang Zhiguang Li Fashen 不详 key {1. for Magnetism and Magnetic Materials of the Ministry of Education Lanzhou University Lanzhou China.

来源：

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

Photochemical Reactions of Unsaturated Carbon-Carbon Bonds

Photochemical Reactions of Unsaturated Carbon-Carbon Bonds

引用

第十五届全国光化学学术讨论会

作者： Wujiong Xia State key Lab of Urban Water Resource and Environment Shenzhen Graduate School Harbin Institute of Technology

Among the light-induced cyclization reactions, the oxidative photocyclization of stilbene is of great interest owing to its preeminent reactivity in photochemistry. Moreover, stilbene derivatives that contain heteroatoms or large conjugated systems on aryl moieties could also undergo the same reaction to give corresponding products. This typical reaction is known as the Mallory reaction and has been extensively investigated for the synthesis of polycyclic aromatic hydrocarbons(PAHs) and other exceptional molecular structures(Fig.1. a). Meanwhile, the trifluoromethyl moiety is one of the prevalent and important groups in functional molecular, agrochemicals, pharmaceuticals and materials, due to its biological activities and physical properties. Among these oxidative difunctionalization of alkenes, radical transformation has been proved to be an attractive strategy to build CF containing molecules . Here, we have developed an efficient approach for the synthesis of α-aryl-β-trifluoromethyl amides and/or CF-containing oxindoles as well as the isoquinolinediones under visible light conditions(Fig.1. b), and the synthesis of phenanthrene derivatives from linear 3-aryl-N-(arylsulfonyl)-propiolamides via tandem radical Smiles rearrangement/C-S bonding/Mallory reaction under UV light conditions(Fig.1. c).

关键词： photochemistry unsaturated carbon-carbon bond radical reaction

来源： cnki会议评论

在线全文

cnki会议

学校读者我要写书评

暂无评论

A chronological review of photochemical reactions of ferrioxalate at the molecular level:New insights into an old story

引用

Chinese Chemical Letters 2023年第5期34卷 38-45页

作者： Xiaodie Li Meiru Hou Yu Fu Lingli Wang Yifan Wang Dagang Lin Qingchao Li Dongdong Hu Zhaohui Wang Shanghai key Lab for Urban Ecological Processes and Eco-Restoration School of Ecological and Environmental SciencesEast China Normal UniversityShanghai 200241China Technology Innovation Center for Land Spatial Eco-Restoration in Metropolitan Area Ministry of Natural ResourcesShanghai 200062China Shanghai Engineering Research Center of Biotransformation of Organic Solid Waste Shanghai 200241China

Owing to its outstanding photoactivity,ferrioxalate is originally used as an actinometer and subsequent work has discovered that photochemistry of ferrioxalate is also fundamentally or technically important in atmospheric chemistry and water *** the overall products generated from photolysis of ferrioxalate are known to include Fe(Ⅱ),a series of oxidizing(e.g.,·OH,O_(2)^(·-)/HO_(2)^(·-))or reducing(C_(2)O_(4)^(·-)/CO_(2)^(·-))radicals and H_(2)O_(2),however,at the molecular level,the primary step of the photoreaction of ferrioxalate remains as an unsolved mystery due to the difficulty in examining such ultrafast *** from the development of time-resolved spectroscopy,this old question has been studied with increasing vigor recently,by means of such ever-more-sophisticated techniques(e.g.,flash photolysis,time-resolved X-ray absorption spectroscopy(XAS),femtosecond infrared(IR)absorption spectroscopy,ultrafast photoelectron spectroscopy(PES)).There are two contrary views on the primary reaction mechanism:(1.Intramolecular electron transfer(ET)precedes the cleavage of the metal-ligand bond;(2)The dissociation of C-C or Fe-O bond occurs before intramolecular ***,this review presents a comprehensive summary about the overall reaction mechanism and molecular level mechanism of *** chronological order,we have elaborated two predominant but controversial views from the perspectives of different experimental *** challenges and research opportunities in this active field are also briefly discussed.

关键词： Ferrioxalate Photolysis Ligand-to-metal charge transfer(LMCT) Time-resolved spectroscopy

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

欢迎您,

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

请选择保存的检索档案：

请选择收藏分类：

通借通还

欢迎您,

建议与咨询 留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

请选择保存的检索档案： 新增检索档案 确定 取消

请选择收藏分类： 新增自定义分类 确定 取消

通借通还

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

请选择保存的检索档案：

请选择收藏分类：