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Mechanism and kinetics of 2-chlorophenol degradation in drinking water by photo-electrochemical synergic effect

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Science China Chemistry 2003年第3期46卷 259-270页

作者： song qiang (宋强) QU Jiuhui (曲久辉) State Key Laboratory of Environmental Aquatic Chemistry Research Center for Eco-Environmental Science Chinese Academy of Sciences Beijing 100085 China State Key Laboratory of Environmental Aquatic Chemistry Research Center for Eco-Environmental Science Chinese Academy of Sciences Beijing 100085 China

The synergic effect mechanism of photo-electrochemical oxidation is investigated in detail through reaction products and kinetics analysis in a photo-electric integral reactor with 2-chlorophenol (2-CP) as the model pollutant. A kinetics model is constructed for the combinatorial photo-electrochemical (CPE) degradation. A remarkable synergetic effect, which can significantly enhance the mineralization rate of the CPE process, is verified by the comparison of apparent kinetic constants. In the CPE process, complemental effects with multi-level and multi-pathway for pollutants degradation under our experimental conditions are speculated. It is proved that the degradation pathways are not only the simple summation of that of photolysis and electrolysis, but the formation of synergic effect through combination of several new acting approaches. The degradation efficiency is enhanced considerably by three factors, control of electrode poisoning by the UV irradiation, control of excitation and reaction trend of pollutants molecules by the UV irradiation, and control of activation effect and transfer trend by the oriented direct current (DC) electric field. An advanced oxidation system is set up through manifold of free radicals chain reactions in the CPE reactions, so that the aqueous organics can be mineralized fast and completely. It is proven by the kinetics analysis that the mineralization of organic pollutants is mainly attributed to the generation of very active hydroxyl radicals (OH@) in bulk solution from the CPE synergetic effect.

关键词： 2-chlorophenol, photo-electrochemical synergic effect, kinetics model, drinking water, microelectrolysis, UV.

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改良型半加成法流程的夹膜处理

印制电路信息 2024年第4期32卷 61-63页

作者：李亮宋强金立奎王辉然曾祥刚周丰林郭文珠海方正科技高密电子有限公司广东珠海519179

0引言随着电子信息技术的发展,印制电路板(printed circuit board,PCB)朝着高度密集化和多样化的方向发展。为了满足终端产品结构精细化、密集化和轻量化发展的要求,越来越多的PCB供应商引进了技术能力更高的改良型半加成法(modifiedsem... 详细信息

0引言随着电子信息技术的发展,印制电路板(printed circuit board,PCB)朝着高度密集化和多样化的方向发展。为了满足终端产品结构精细化、密集化和轻量化发展的要求,越来越多的PCB供应商引进了技术能力更高的改良型半加成法(modifiedsemi-additiveprocess,mSAP)工艺流程,在流程制作上导入压载体铜箔、沉铜闪镀、填孔图形电镀和退膜闪蚀等关键工序。由于终端产品个性化与多元化设计的差异,PCB的图形设计结构千差万别,通常会出现孤立特征图形与密集特征图形,在垂直填孔图形电镀时,其电力线分布受到图形设计影响,导致局部位置出现夹膜异常。

关键词：印制电路板半加成法图形电镀填孔改良型终端产品多元化设计密集化

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堆载作用下楔形桩负摩阻力演化特性研究

建筑技术开发 2024年第7期51卷 92-94页

作者：孙松强刘斌王志远朱美甜李晓梦浙江华东工程建设管理有限公司杭州310030 郑州科技学院郑州450064

通过分析地面堆载因素造成的桩周土体沉降所引起负摩阻力的特性,对了解与掌握桩基负摩阻力特性具有重要的理论意义,但如何减轻堆载引起的负摩阻力,对工程更有实际意义。研究采用FLAC 3D有限差分法,分析了堆载作用对楔形桩基负摩阻力和... 详细信息

通过分析地面堆载因素造成的桩周土体沉降所引起负摩阻力的特性,对了解与掌握桩基负摩阻力特性具有重要的理论意义,但如何减轻堆载引起的负摩阻力,对工程更有实际意义。研究采用FLAC 3D有限差分法,分析了堆载作用对楔形桩基负摩阻力和中性点的影响,研究结果表明:无论堆载大小,楔形桩桩身轴力随深度的增大而增大,待其达到某一峰值时,桩身轴力减小。当桩周土堆载不大于7.5 kPa时,随着堆载的增大,轴力也随之明显增大;而当桩周土堆载大于7.5 kPa时,随着堆载的增大,轴力虽然也略有增大,但其增长幅度较小。堆载作用下楔形桩中性点稳定深度为–0.3~–0.4 m间。当桩周土堆载较大时,可采用轴力最大点、摩阻力零值、相对位移零值计算中性点位置;而当堆载较小时,则利用轴力最大点和摩阻力零值计算中性点位置更为可靠。

关键词：楔形桩负摩阻力中性点相对位移有限元

Spatial compartmentalization and temporal stability of associated microbiota in Pacific oyster Crassostrea gigas

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Journal of Oceanology and Limnology 2024年第4期42卷 1348-1358页

作者： qiang FU Zichao YU Junyan ZHAO Lei GAO Ning KONG Lingling WANG Linsheng song Liaoning Key Laboratory of Marine Animal Immunology and Disease Control Dalian Ocean UniversityDalian 116023China Functional Laboratory of Marine Fisheries Science and Food Production Processes Qingdao National Laboratory for Marine Science and TechnologyQingdao 266237China Southern Marine Science and Engineering Guangdong Laboratory(Zhuhai) Zhuhai 519000China Dalian Key Laboratory of Aquatic Animal Disease Prevention and Control Dalian Ocean UniversityDalian 116023China

The Pacific oyster Crassostrea gigas,one of the most exploited molluscs in the world,has suffered from massive mortality in recent decades,and the occurrence mechanisms have not been well *** this study,to reveal the relationship of associated microbiota to the fitness of oysters,temporal dynamics of microbiota in the gill,hemolymph,and hepatopancreas of *** during April 2018-January 2019 were investigated by 16 S rRNA gene *** microbiota in *** exhibited tissue heterogeneity,of which Spirochaetaceae was dominant in the gill and hemolymph while Mycoplasmataceae enriched in the ***-occurrence network demonstrated that the gill microbiota exhibited higher inter-taxon connectivity while the hemolymph microbiota had more *** richness(Chao 1 index)and diversity(Shannon index)of microbial community in each tissue showed no significant seasonal variations,except for the hepatopancreas having a higher richness in the ***,beta diversity analysis indicated a relatively stable microbiota in each tissue during the sampling period,showing relative abundance of the dominant taxa exhibiting temporal *** indicate that the microbial community in *** showed a tissue-specific stability with temporal dynamics in the composition,which might be essential for the tissue functioning and environmental adaption in *** work provides a baseline microbiota in *** and is helpful for the understanding of host-microbiota interaction in oysters.

关键词： Pacific oyster associated microbiota spatial compartmentalization temporal stability

Recent advances in electrocatalytic generation of indole-derived radical cations and their applications in organic synthesis

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Chinese Chemical Letters 2024年第4期35卷 106-123页

作者： Wei Zhou Xi Chen Lin Lu Xian-Rong song Mu-Jia Luo qiang Xiao Key Laboratory of Organic Chemistry of Jiangxi Province Jiangxi Science&Technology Normal UniversityNanchang 330013China

Indole-derived radical cations, open-shell reactive species, display distinctive dual reactivity due to the carbon-centered radical and more electrophilic carbocation, which frequently appear in a variety of single electron oxidation reactions for synthesizing structurally diverse functionalized indoles and indolines. Electrocatalysis is considered as a synthetically attractive and environmentally friendly alternative for driving the single electron oxidation of indoles. Remarkable achievements in electrocatalytic indolederived radical cation-mediated indole functionalization have been realized so far. This review comprehensively summarizes the recent progresses in the applications of electrocatalytic indole radical cations,including C(sp~2)–H functionalization, dearomative 2,3-difunctionalization, and ring-opening reaction, emphasizing the vital single electron oxidation steps of indoles, the substrates scope and limitations, and the reaction mechanisms.

关键词： Electrocatalysis Indole radical cation C-H functionalizatin Dearomative 2 3-difunctionalization

Selective growth of SiC nanowires in interlaminar matrix for improving in-plane strengths of laminated Carbon/Carbon composites

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Journal of Materials Science & Technology 2019年第12期35卷 2799-2808页

作者： qiang song Qingliang Shen qiangang Fu Hejun Li State Key Laboratory of Solidification Processing Carbon/Carbon Composites Research Center Northwestern Polytechnical University

β-SiC nanowires(SiCNWs) were selectively grown in the interlaminar matrix with a volume fraction of0.65% by applying a pyrocarbon coating on carbon fibers, which realizes the proper reinforcement of C/C composites. The thickness of the pyrocarbon is optimized to 0.5 μm based on the analysis of in-situ fiber strengths with the fracture mirror method. The pyrocarbon coating increased the in-situ fiber strength by^7% and prevent brittle fracture of the composites. Compared with C/C, the interlaminar shear and flexural strength of SiCNW-C/C(10.06 MPa and 162.44 MPa) increase by 158% and 57%. Incorporating SiCNWs changes the crystallite orientations and refines the crystallite size of pyrocarbon matrix. The functions of SiCNWs vary with their loading density. When SiCNWs are sufficient in the matrix, they help reinforcing and improving the critical failure stress of the matrix. When their density decreases to a certain degree, SiCNWs help changing the crystallite orientations of pyrocarbon and toughening the matrix.

关键词： Carbon/carbon composites SiC nanowire Interlaminar strength

Dynamics of Polymeric Fluids：Part Ⅱ The Molecular Theory of Die Swell： Correlation of Ultimate Die Swelling Effect to the Molecular Parameters and the Operational Variables

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Journal of Materials Science & Technology 2006年第5期22卷 664-676页

作者： Mingshi song qiang XU Guixian HU Sizhu WU Key Laboratory of Science and Technology of Controlled Chemical Reactions Beijing University of Chemical TechnologyBeijing 100029 China

A general expression for the correlation of the simple shear （tanφ） to the molecular parameters and the shear rate （·↑γ） was deduced. It shows that the simple shear （tanφ） may be resolved into free recoil （recoverable strain） and viscous heating （unrecoverable strain）. The magnitudes of the simple shears for recoil （tanφE） and （tanφv） for viscous heating not only depended on the molecular parameters and the operational variables, but also on the exponential fractions of the recoverable （1--↑W·↑γ） and unrecoverable （-↑W·↑γ） conformations for recoil and viscous heating. Therefore the magnitudes of the simple shears （tanφE） for recoil and （tanφv） for viscous heating are, respectively, expressed as the partition function to the （1--↑W·↑γ）th power and the partition function to the （-↑W·↑γ）th power. Thus correlations of the total recoil and the ultimately recoverable strains to the molecular parameters [n′, α, η0, GN^0 and （1--↑W·↑γ）] and the operational variables （·↑γ, （L/D） and tr） were deduced respectively, which show that at very different shear rates （0≤·↑γ≤∞） the polymeric liquids may exhibit a very different viscoelastic behaviors. After introducing the uniform two-dimensional extension, the definition of swelling ratio and the ratio of L to D [De=（L/D）], two expressions for the ultimate die swelling effect and the ultimate extrudate swelling ratio BEVT5 to the molecular parameters [n′, α, η0, GN^0 and （1--↑W·↑γ）] and the operational variables （·↑γ, （L/D） and tr） were obtained. The two correlation expressions were verified by the experimental data of high-density polyethylene （HDPE） which shows that the two correlation expressions can be used to predict the correlations of the ultimate extrudate swelling behaviors of polymeric liquids to the molecular parameters and the operational variables.

关键词： Die swell Viscoelastic recoil Entanglement

Enhancing both strength and toughness of carbon/carbon composites by heat-treated interface modification

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Journal of Materials Science & Technology 2019年第3期35卷 383-393页

作者： Jiajia Sun Hejun Li Liyuan Han qiang song State Key Laboratory of Solidification Processing Northwestern Polytechnical University

A simple method to increase both strength and toughness of carbon/carbon(C/C) composites is *** method is based on the heat treatment of the pre-deposited thin carbon coating, leading to the formation of more orderly pyrolytic carbon(PyC) as a functional interlayer between fiber and matrix that could optimize the interfacial sliding strength in C/C composites. Effects of such a heat-treated PyC layers on the microstructure, tensile strength and fracture behavior of unidirectional C/C composites were investigated. Results showed that although the in-situ fiber strength was deteriorated after the introduction of interfacial layer, tensile strength of the specimen was greatly improved by 38.5% compared with pure C/C composites without any treatment. The interfacial sliding stress sharply decreased, which was interpreted from finite element analysis and verified by Raman spectra. Therefore, the fracture behavior was changed from brittle fracture to multiple-matrix cracking induced non-linear mechanical ***, the ultimate strength can be predicted by different models according to the interfacial sliding stress. Our research would provide a meaningful way to improve both strength and toughness of C/C composites.

关键词： Carbon/carbon composites Tensile strength Interface Heat treatment

New Frontiers on Intracellular cGAS Activation:Molecular Mechanisms,Cellular Signaling,and Therapeutic Strategies

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Chemical Research in Chinese Universities 2024年第4期40卷 632-645页

作者： song Xingrui LING Xiaoting LIU Hailong ZHAO qiang LI Xiangjun LAI Weiyi WANG Hailin State Key Laboratory of Environmental Chemistry and Ecotoxicology Research Center for Eco-Environmental SciencesChinese Academy of SciencesBeijing10085P.R.China School of Chemical Sciences University of Chinese Academy of SciencesBeijing101408P.R.China

Cyclic GMP-AMP(cGAMP)synthase(cGAS)plays a pivotal role in the innate immune *** the primary DNA sensor in cells,cGAS binds to dsDNA in the cytoplasm and forms cGAS-DNA liquid-liquid phase separation(LLPS)and activates its catalytic *** activation triggers the cGAS-stimulator of interferon genes(STING)signaling pathway,establishing an efficient system for pathogen *** pathogen surveillance,cGAS performs a diverse range of roles,involved in inflammatory response,metabolic homeostasis,DNA damage repair,and cell *** biological functions regulate cellular physiological homeostasis and influence the occurrence and development of *** review provides an overview of the structure,localization,and intracellular biological functions of the cGAS-STING signaling pathway and cGAS-DNA ***,we discuss their contribution to the development of tumors,autoimmune diseases,and inflammatory diseases and highlight the innovative strategies in modulating cGAS activity,either through activation or inhibition,as a promising therapeutic approach.

关键词： Cyclic GMP-AMP(cGAMP)synthase(cGAS)-stimulator of interferon genes(cGAS-STING) Liquid-liquid phase separation(LLPS) Biological function Disease