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Chinese Journal of Chemistry 1984年第1期2卷 13-17页

作者： LI Zong-Zhen ni chau-zhou MA Yi-Lin Shanghai Institute of Organic Chemistry Academia Sinica,Shanghai Shanghai Institute of Organic Chemistry Academia Sinica Shanghai

The title reaction gave three known compounds（2,3 and 4）and two new compounds,CH3SCH2（CF2）2H（5）and I（C2）2O（CF2）2SO3-S+（CH3）3（6）.The structure of 6 was confirmed by X-raydiffraction *** crystals of 6 belong to monoclinic space group P21/C with a=9.399,b=15.651,c=10.934A,β=94.80°and z=*** structure was solved by heavy-atom method andrefined by block-diagonal matrix least-squares procedure to a final R of 0.054 for 1999 independentobserved *** S-C bonds around the sulphur atom in trimethylsulphonium are pyramidal with the bondlengths of 1.814A,1.800 A and 1.818 A and the bond angles C-S-C of 101.06°,101.52°and 102.53°.The distances of the sulphur atom in trimethylsulphonium to three oxygen atoms in the sulphonateradical are 3.79 A,*** 3.34 A *** distances are out of the range of the normalS-O bond *** structure consists of trimethylsulphonium cations and 5-iodo-3-oxaoctafluoro-pentane-sulphonate anions.

关键词： The reaction of 2’2’3’3 tetrafluoropropyl-5-iodo-3-oxaoctafluoropentane sulfonate with dimethylsulfoxide and determination of the crystal structure of one of the products

5—碘—3—氧杂—八氟戊磺酸—2’,2’,3’,3’—四氟丙酯与二甲亚砜的反应及结晶产物的晶体结构测定

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化学学报 1984年第2期42卷 120-124页

作者：李宗珍倪朝周马益林中国科学院上海有机化学研究所

标题反应产生三个已知化合物2,3,4和两个新的化合物CH3SCH2CF2CF2H（5）和I（CF2）2O（CF2）2SO3-+S（CH3）3（6）。6的结构经X射线衍射测定得到验证。 6的晶体属单斜晶系,空间群为P21/c;晶胞参数a=9.399A,b=15.651A,C=10.934A,β=94.80°;V=1602.8A3;Z=4;Dm=2.072gcm-3,Dc=2.073gcm-3。结构由重原子法解出,经各向同性和各向异性块对角矩阵最小二乘修正,对1999个可观察衍射点,最终R值为0.054。三甲基锍中的三个S-C键形成三棱锥体,其键长分别为1.814,1.800,1.818A,三个C-S-C键角为101.06°,101.52°,102.53°。三甲基锍中的S原子与磺酸根中三个O原子的距离分别为3.79,3.64,3.43A,大大超过S-O共价键的键长范围。整个晶体是由[（CH3）3S]+和[I（CF2）2O（CF2）2SO3]-组成的离子晶体。

关键词：晶体结构测定二甲四氟结晶学晶体学地质学产物磺酸硫化合物反应

Oxidation of emerging organic contaminants by in-situ H_(2)O_(2) fenton system

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Green Energy & Environment 2024年第3期9卷 417-434页

作者： Yuqin ni Chuxiang zhou Mingyang Xing Yi zhou State Environmental Protection Key Lab of Environmental Risk Assessment and Control on Chemical Processes School of Resources&Environmental EngineeringEast China University of Science and TechnologyShanghai200237China Key Laboratory for Advanced Materials and Institute of Fine Chemicals National Engineering Laboratory for Industrial Wastewater TreatmentSchool of Chemistry and Molecular EngineeringEast China University of Science and Technology130 Meilong RoadShanghai200237China Department of Applied Natural Sciences Technische Hochschule LubeckMonkhofer Weg 23923562 LubeckGermany

The existence and risk of emerging organic contaminants(EOCs)have been under consideration and paid much effort to degrade these *** system is one of the most widely used technologies to solve this *** original Fenton system relies on the hydroxyl radicals produced by Fe(Ⅱ)/H_(2)O_(2) to oxidize the organic ***,the application of the Fenton system is limited by its low iron cycling efficiency and the high risks of hydrogen peroxide transportation and *** introduction of external energy(including light and electricity etc.)can effectively promote the Fe(Ⅲ)/Fe(Ⅱ)cycle and the reduction of oxygen to produce hydrogen peroxide in *** review introduces three in-situ Fenton systems,which are electro-Fenton,Photo-Fenton,and chemical *** mechanism,influencing factors,and catalysts of these three in-situ Fenton systems in degrading EOCs are discussed *** review strengthens the understanding of Fenton and in-situ Fenton systems in degradation,offering further insight into the real application of the in-situ Fenton system in the removal of EOCs.

关键词： In-situ H_(2)O_(2)production Fenton Emerging organic contaminants Photocatalysis Electrocatalysis

Enhancing plant-microbe associated bioremediation of phenanthrene and pyrene contaminated soil by SDBS-Tween 80 mixed surfactants

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Journal of Environmental Sciences 2014年第5期26卷 1071-1079页

作者： Hewei ni Wenjun zhou Lizhong Zhu Department of Environmental Science Zhejiang University Zhejiang Provincial Key Laboratory of Organic Pollution Process and Control

The use of surfactants to enhance plant-microbe associated dissipation in soils contaminated with polycyclic aromatic hydrocarbons （PAHs） is a promising bioremediation technology. This comparative study was conducted on the effects of plant-microbe treatment on the removal of phenanthrene and pyrene from contaminated soil, in the presence of low concentration single anionic, nonionic and anionic-nonionic mixed surfactants. Sodium dodecyl benzene sulfonate （SDBS） and Tween 80 were chosen as representative anionic and nonionic surfactants, respectively. We found that mixed surfactants with concentrations less than 150 mg/kg were more effective in promoting plant-microbe associated bioremediation than the same amount of single surfactants. Only about （m/m） of mixed surfactants was needed to remove the same amount of phenanthrene and pyrene from either the planted or unplanted soils, when compared to Tween 80. Mixed surfactants （〈 150 mg/kg） better enhanced the degradation efficiency of phenanthrene and pyrene via microbe or plant-microbe routes in the soils. In the concentration range of 60-150 mg/kg, both ryegrass roots and shoots could accumulate 2-3 times the phenanthrene and pyrene with mixed surfactants than with Tween 80. These results may be explained by the lower sorption loss and reduced inteffacial tension of mixed surfactants relative to Tween 80, which enhanced the bioavailability of PAHs in soil and the microbial degradation efficiency. The higher remediation efficiency of low dosage SDBS-Tween 80 mixed surfactants thus advanced the technology of surfactant-enhanced plant-microbe associated bioremediation.

关键词： polycyclic aromatic hydrocarbons contaminated soil plant-microbe associated bioremediation ryegrass

Electronic structure,bonding characteristics,and mechanical behaviors of a new family of Si-containing damage-tolerant MAB phases M_(5)SiB_(2)(M=IVB-VIB transition metals)

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Journal of Advanced Ceramics 2022年第10期11卷 1626-1640页

作者： Na ni Hanchao ZHANG Yanchun zhou School of Mechanical Engineering Shanghai Jiao Tong UniversityShanghai 200240China Science and Technology on Advanced Functional Composite Laboratory Aerospace Research Institute of Materials&Processing TechnologyBeijing 100076China

MAB phases are layered ternary compounds with alternative stacking of transition metal boride layers and group A element *** now,most of the investigated MAB phases are concentrated on compounds with Al as the A element *** this work,the family of M_(5)SiB_(2)(M=IVB-VIB transition metals)compounds with silicon as interlayers were investigated by density functional theory(DFT)methods as potential MAB phases for high-temperature *** from the known Mo5SiB2,the electronic structure,bonding characteristics,and mechanical behaviors were systematically investigated and *** the composition of M_(5)SiB_(2) does not follow the general formula of experimentally reported(MB)_(2z)A_(x)(MB_(2))_(y)(z=1,2;x=1,2;y=0,1,2),their layered structure and anisotropic bonding characteristics are similar to other known MAB phases,which justifies their classification as new members of this material *** a result of the higher bulk modulus and lower shear modulus,Mo_(5)SiB_(2) has a Pugh’s ratio of 0.53,which is much lower than the common MAB *** was found that the stability and mechanical properties of M_(5)SiB_(2) compounds depend on their valence electron concentrations(VECs),and an optimum VEC exists as the criteria for *** hypothesized Zr and Hf containing compounds,i.e.,Zr_(5)SiB_(2) and Hf_(5)SiB_(2),which are more interesting in terms of high-temperature oxidation/ablation resistance,were found to be unfortunately *** cope with this problem,a new stable solid solution(Zr_(0.6)Mo_(0.4))_(5)SiB_(2) was designed based on VEC tuning to demonstrate a promising approach for developing new MAB phases with desirable compositions.

关键词： borides MAB phases density functional theory(DFT) thermodynamic stability electronic structure mechanical properties

How defects influence the photoluminescence of TMDCs

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Nano Research 2021年第1期14卷 29-39页

作者： Mengfan zhou Wenhui Wang Junpeng Lu Zhenhua ni School of Physics and Key Laboratory of MEMS of the Ministry of Education Southeast UniversityNanjing 211189China

Two-dimensional(2D)transition metal dichalcogenide(TMDC)monolayers,a class of ultrathin materials with a direct bandgap and high exciton binding energies,provide an ideal platform to study the photoluminescence(PL)of light-emitting *** thin TMDCs usually contain various defects,which enrich the lattice structure and give rise to many intriguing *** the influences of defects can be either detrimental or beneficial,a comprehensive understanding of the internal mechanisms underlying defect behaviour is required for PL ***,recent advances in the defect influences on PL emission are summarized and *** mechanisms are the focus of this review,such as radiative/nonradiative recombination kinetics and band structure *** challenges and opportunities are present in the field of defect manipulation,and the exploration of mechanisms is expected tofacilitate the applications of 2D TMDCs in the future.

关键词： two-dimensional material transition metal dichalcogenides(TMDCs) photoluminescence(PL) defect defect engineering quantum yield(QY)

Discrete element method study of hysteretic behavior and deformation characteristics of rockfill material under cyclic loading

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2023年第4期24卷 350-365页

作者： Mingchun LIN Guanqi WANG Jian zhou Wei zhou ni AN Gang MA State Key Laboratory of Water Resources and Hydropower Engineering Science Wuhan UniversityWuhan 430072China Institute of Water Engineering Sciences Wuhan UniversityWuhan 430072China Power China Chengdu Engineering Co. Ltd.Chengdu 610072China Power China Kunming Engineering Co. Ltd.Kunming 650051China

Granular geomaterials under different loading conditions manifest various behaviors,such as *** their hysteretic behavior and deformation characteristics is the basis for establishing a constitutive relation with excellent performance in deformation *** deformation characteristics of crushable particle materials are analyzed through a series of cyclic loading tests conducted by numerical *** hysteretic behavior is investigated from a particle *** increase in particles with contacts less than two may be responsible for the residual strain,and the particle breakage further promotes particle rearrangement and volume *** the accumulation of plastic strain and the resilient modulus are found to be related to confining pressures,stress levels,cyclic loading amplitudes,and the number of *** plastic strain accumulation can be written as a function of the number of cycles and an evolution function of resilient modulus is proposed.

关键词： Granular material Discrete element method(DEM) Plastic deformation Cyclic loading Hysteretic behavior

Application of Nd:YAG Laser Welding to Implantable Neuro-Stimulator

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Chinese Journal of Mechanical Engineering 2011年第6期24卷 1103-1110页

作者： zhou Zhenggan ni Xiansheng WEN Xiongwei LI Luming Institute for Nondestructive Testing and Mechatronics Engineering Beihang University Beijing 100191 China Tsinghua Space Center Tsinghua University Beijing 100084 China

It is difficult to weld the material and structure of implantable neuro-stimulator such as pure medical titanium and irregular outside shield by conventional arc welding *** there are few reports on the neuro stimulator sealing technology,and none of them have simultaneously considered the quality control *** order to develop the sealing procedure and quality control methods,an investigation of applying Nd：YAG laser welding to implantable neuro-stimulator components is carried ***,the automatic Nd：YAG laser welding system equipped with proper fixture configuration is introduced.A special fixture structure is illustrated and the key point for the device is to reduce the fit-up gap between the two ***,a novel welding process technique is proposed to satisfy the engineering *** optimized process parameters for titanium shell,feedthrough and fastener are provided and concluded by an orthogonal ***,different quality control measures such as visual inspection,X-ray detecting and leakage testing,are presented on the final *** results show that the Nd：YAG laser welding applied on the implanted neuro-stimulator under optimized parameters can prevent welding defects and improve the weld joints *** of various quality control methods will guarantee the sealing performance and mechanical properties of the *** is confirmed that the processing procedure and quality methods can not only resolve the process technology on welding ultra-thin structure of medical device,but also provide the reference for other implantable device.

关键词： laser beam welding titanium process technique quality control nondestructive testing (NDT)

Research on the Error Averaging Effect in A Rolling Guide Pair

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Chinese Journal of Mechanical Engineering 2019年第4期32卷 104-115页

作者： Yanbing ni Haiyang zhou Cuiyan Shao Jinhe Li Key Laboratory of Mechanism Theory and Equipment Design of Ministry of Education Tianjin University

By studying the e ects of geometric precision on kinematic accuracy, an error mapping model has been established, based on the hypothesis that a motion pair and its installation surface are rigid. However, when using this assumption,there is a significant error induced in high-precision computer numerical control(CNC) machine tools as compared with reality. One of the most important reasons for this error is failing to consider the error averaging e ect of motion pair elements. Therefore, this work examines a high-precision horizontal machining center as its research object, and analyzes the error averaging mechanism of a rolling guide pair under a deformation of the rolling elements. The carriage bearing forces caused by guideway straightness errors are obtained by constructing a geometric error model of a single carriage. The relationship between guideway straightness errors and carriage bearing forces is described by a transfer function in the spatial frequency domain, and its characteristics are analyzed. It quantifies the so-called error averaging e ect of the rolling guide system and, on this basis, a static model for four carriages is established to reflect the error averaging e ect of the rolling guide pair on the position and orientation errors of the motion pair. In addition, it is found that the wavelengths and phase di erences of guideway errors a ect this error averaging mechanism, but the amplitude and preload have little influence thereon. The experiment result shows that the kinematic straightness errors in the x-and y-directions were approximately 1/3 to 1/2 of the guideway straightness errors in the corresponding directions. The results can be used to guide the precision design and assembly of machine tools.

关键词： Rolling guide pair Error averaging mechanism Guideway straightness errors Precision design

CRISPR-mediated acceleration of wheat improvement:advances and perspectives

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Journal of Genetics and Genomics 2023年第11期50卷 815-834页

作者： Ximeng zhou Yidi Zhao Pei ni Zhongfu ni Qixin Sun Yuan Zong Frontiers Science Center for Molecular Design Breeding Key Laboratory of Crop Heterosis and UtilizationBeijing Key Laboratory of Crop Genetic ImprovementChina Agricultural UniversityBeijing 100193China

Common wheat(Triticum aestivum)is one of the most widely cultivated and consumed crops *** the face of limited arable land and climate changes,it is a great challenge to maintain current and increase future wheat *** agronomic traits in wheat by introducing mutations across all three homoeologous copies of each gene has proven to be a difficult task due to its large genome with high ***,clustered regularly interspaced short palindromic repeat(CRISPR)/CRISPR-associ-ated nuclease(Cas)genome editing technologies offer a powerful means of precisely manipulating the genomes of crop species,thereby opening up new possibilities for biotechnology and *** this review,we first focus on the development and optimization of the current CRISPR-based genome editing tools in wheat,emphasizing recent breakthroughs in precise and multiplex genome *** then describe the general procedure of wheat genome editing and highlight different methods to deliver the genome editing reagents into wheat ***,we summarize the recent applications and ad-vancements of CRISPR/Cas technologies for wheat ***,we discuss the remaining chal-lenges specific to wheat genome editing and its future prospects.

关键词： Common wheat CRISPR/Cas Precise genome editing Delivery Wheat improvement