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Optoelectronics Letters 2023年第9期19卷 548-555页

作者： WANG Jiangchao XUE Yuming DAI Hongli WANG Luoxin ZHANG Jiuchao HU Zhaoshuo Institute of New Energy Intelligence Equipment School of Integrated Circuit Science and EngineeringTianjin University of TechnologyTianjin 300384China

LiNi_(0.8)Co_(0.1)Mn_(0.1)O_(2)cathode material is prepared by sol-gel method and the effects of Nb^(5+)doping and different calcination temperatures on cathode materials were deeply investigated.structural and morphological characterizations revealed that the optimal content of 1 mol%Nb^(5+)can stabilize layered structures,mitigate Ni^(2+)migration to Li layers,improve lithium diffusion capacity,and reduce lattice expansion/shrinkage while cycling.And calcination temperature at 800℃can not only ensure good morphology,but also suppress the mixed discharge of lithium and nickel in the internal structure.Electrochemical performance evaluation revealed that Nb^(5+)doping improves the discharge-specific capacity of the material,which is conducive to ameliorating its rate capability and cycle performance.And the material at 800℃exhibits the highest discharge specific capacity,the best magnification performance,low polarizability,and the best cycle reversibility.

关键词： O_(2)cathode materials at different calcination temperatures for lithium-ion batteries structural doped LiNi electrochemical and cycling properties of Nb

structural confirmation of sulconazole sulfoxide as the primary degradation product of sulconazole nitrate

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Journal of Pharmaceutical Analysis 2018年第2期8卷 96-102页

作者： Qun Xu Ashraf Khan Di Gao Kristie M.Adams Fatkhulla Tadjimukhamedov Shane Tan John T.Simpson Compendial Development Laboratory United States Pharmacopeia

Sulconazole has been reported to degrade into sulconazole sulfoxide via sulfur oxidation; however,structural characterization data was lacking and the potential formation of an N-oxide or sulfone could not be excluded. To clarify the degradation pathways and incorporate the impurity profile of sulconazole into the United States Pharmacopeia–National Formulary(USP–NF) monographs, a multifaceted approach was utilized to confirm the identity of the degradant. The approach combines stress testing of sulconazole nitrate, chemical synthesis of the degradant via a hydrogen peroxide-mediated oxidation reaction,semi-preparative HPLC purification, and structural elucidation by LC–MS/MS and NMR spectroscopy.structural determination was primarily based on the comparison of spectroscopic data of sulconazole and the oxidative degradant. The mass spectrometric data have revealed a Mc Lafferty-type rearrangement as the characteristic fragmentation pathway for alkyl sulfoxides with a β-hydrogen atom, and was used to distinguish the sulfoxide from N-oxide or sulfone derivatives. Moreover, the generated sulconazole sulfoxide was utilized as reference material for compendial procedure development and validation, which provides support for USP monograph modernization.

关键词： Sulconazole nitrate Sulconazole sulfoxide Forced degradation structural characterization LC–MS/MS

structural simplification: an efficient strategy in lead optimization

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Acta Pharmaceutica Sinica B 2019年第5期9卷 880-901页

作者： Shengzheng Wang Guoqiang Dong Chunquan Sheng Department of Medicinal Chemistry School of PharmacySecond Military Medical UniversityShanghai200433China Department of Medicinal Chemistry and Pharmaceutical Analysis School of PharmacyFourth Military MedicalUniversityXi’an710032China

The trend toward designing large hydrophobic molecules for lead optimization is often associated with poor drug-likeness and high attrition rates in drug discovery and development. structural simplification is a powerful strategy for improving the efficiency and success rate of drug design by avoiding 'molecular obesity'. The structural simplification of large or complex lead compounds by truncating unnecessary groups can not only improve their synthetic accessibility but also improve their pharmacokinetic profiles, reduce side effects and so on. This review will summarize the application of structural simplification in lead optimization. Numerous case studies, particularly those involving successful examples leading to marketed drugs or drug-like candidates, will be introduced and analyzed to illustrate the design strategies and guidelines for structural simplification.

关键词： structural simplification Lead optimization Drug discovery Drug design Reducing rings number Reducing chiral centers Structure-based simplification Pharmacophore-based simplification

structural variation in complex genome: detection, integration and function

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Science China(Life Sciences) 2019年第8期62卷 1098-1100页

作者： Ning Yang Shenshen Wu Jianbing Yan National Key Laboratory of Crop Genetic Improvement Huazhong Agricultural University

structural variations (SVs) are mutations with large-scale changes (generally>50 bp) in the genome. SVs are major sources of the genetic diversity of organisms and thus are of high relevance to phenotype variations, gene dosage and evolutionary genetics. Except detecting SVs through comparative genetic analyses, dozens of software had been developed based on the alignment of short-reads to a single linear genome in the past decades (Guan and Sung, 2016).

关键词： pro structural variation in complex genome integration and function

structural form selection of the high-rise buildingwith the improved BP neural network

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High Technology Letters 2020年第1期26卷 92-97页

作者：赵光哲 Yang Hanting Tu Bing Zhou Meiling Zhou Chengle School of Electrical and Information Engineering Beijing University of Civil Engineeringand ArchitectureBeijing 100044P.R.China College of Information and Communication Engineering Hunan Institute of Science and TechnologyYueyang 414000P.R.China

As civil engineering technology development,the structural form selection is more and more critical in design of high-rise buildings.However,structural form selection involves expertise knowledge and changes with the environment which makes the task arduous.An approach utilizing improved back propagation(BP)neural network optimized by the Levenberg-Marquardt(L-M)algorithm is proposed to extract the main controlling factors of structural form selection.Then,an intelligent expert system with artificial neural network is constructed to design high-rise buildings structure effectively.The experiment tests the model in 15 well-known architecture samples and get the prediction accuracy of 93.33%.The results show that the method is feasible and can help designers select the appropriate structural form.

关键词： back propagation(BP)neural network high-rise building structural form selection Levenberg-Marquardt(L-M)algorithm

Heat treatment effect on structural evolution and hydrogen sorption properties of Y_(0.5)La_(0.2)Mg_(0.3-x)Ni_(2) compound

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Rare Metals 2023年第6期42卷 1813-1820页

作者： Hao Shen Li-Jun Jiang Ping Li Hui-Ping Yuan Zhi-Nian Li Jun-Xian Zhang National Engineering Research Center of Nonferrous Metals Materials and Products for New Energy GRINM Group Co.Ltd.Beijing100088China Institute for Advanced Materials and Technology University of Science and TechnologyBeijing100083China CNRS ICMPEUMR 7182Univ Paris Est CreteilThiais94320France GRIMAT Engineering Institute Co. Ltd.Beijing101407China

The effect of heat treatment on phase occurrence,crystal structures and hydrogen sorption properties of Y_(0.5)La_(0.2)Mg_(0.3-x)Ni_(2) compounds has been investigated.The targeted compounds were synthesized through induction melting and processed heat treatment at 700 and 900℃,respectively.Phase occurrence and structural properties were studied by X-ray powder diffraction(XRD).The global compositions and phase compositions have been determined by inductively coupled plasma-optical emission spectrometer(ICP-AES) and electron probe microanalysis(EPMA) respectively.

关键词： hydrogen treatment structural

structural whiteness of the multi-component glaze dependence on amorphous photonic crystals

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Frontiers of Materials Science 2019年第2期13卷 206-215页

作者： Hongquan ZHAN Chuanqi WU Ce DENG Xiaohong LI Zhipeng XIE Changan WANG School of Materials Science and Engineering Jingdezhen Ceramic Institute Jingdezhen 333001 China State Key Lab of New Ceramics and Fine Processing School of Materials Science and Engineering Tsinghua University Beijing 100084 China

A kind of enhancing mechanism of structural whiteness dependence on amorphous photonic crystal (APC) structure is introduced in this paper. In the glaze system composed of albite, kaolin, talc, calcite, quartz, titanium dioxide and zinc oxide, the APC structure will be produced by using quartz as a variable to induce the phase separation. Under different polarities between Ti, Zn etc. and Siion, the separated spheres with the core-shell structure can be obtained and then make up opal-like APCs in the glaze layer. In addition to inner and outer layers of core-shell spheres, the calculated results of refractive indices clearly show the great difference between the particles and the matrix. As a result of different refractive indices, the multiple scatting of visible light plays a key rote in the structural whiteness. However, due to the decrease of the cationic content, APCs with the reverse opal structure would be formed in the interface between glaze and body. Ultimately, the glaze appearance reveals extremely high structural whiteness due to the special APC structure.

关键词： structural whiteness amorphous photonic crystal core-shell structure

structural parameter design method for a fast-steering mirror based on a closed-loop bandwidth

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Frontiers of Mechanical Engineering 2020年第1期15卷 55-65页

作者： Guozhen CHEN Pinkuan LIU Han DING School of Mechanical Engineering Shanghai Jiao Tong UniversityShanghai 200240China

When a fast-steering mirror(FSM)system is designed,satisfying the performance requirements before fabrication and assembly is vital.This study proposes a structural parameter design approach for an FSM system based on the quantitative analysis of the required closed-loop bandwidth.First,the open-loop transfer function of the FSM system is derived.In accordance with the transfer function,the notch filter and proportional-integral(PI)feedback controller are designed as a closed-loop controller.The gains of the PI controller are determined by maximizing the closed-loop bandwidth while ensuring the robustness of the system.Then,the two unknown variables of rotational radius and stiffness in the open-loop transfer function are optimized,considering the bandwidth as a constraint condition.Finally,the structural parameters of the stage are determined on the basis of the optimized results of rotational radius and stiffness.Simulations are conducted to verify the theoretical analysis.A prototype of the FSM system is fabricated,and corresponding experimental tests are conducted.Experimental results indicate that the bandwidth of the proposed FSM system is 117.6 Hz,which satisfies the minimum bandwidth requirement of 100 Hz.

关键词： fast-steering mirror structural parameter PI controller bandwidth notch filter

The early days of structural biology at the Beijing Institute of Biophysics:In memory of Professor Zhengjiong Lin(1935-2022)

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Protein & Cell 2022年第12期13卷 869-872页

作者： Jia-huai Wang Dana-Farber Cancer Institute Harvard Medical SchoolBostonUnited States

At the end of 2017,while I was cleaning my apartment in Beijing,a thin journal caught my attention deep in one dusty cabinet.To my surprise,it was an old lab notebook I used 55 years ago!I could not help opening it.Written on the first page was my mentor Zhengjiong Lin's assignment for my first project:To determine the crystal structure of a di-pep-tide,Proline-Glycine.

关键词： journal assignment structural

Disrupted association between structural and functional coupling of the supplementary motor area and neurocognition in major depressive disorder

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Chinese Medical Journal 2023年第17期136卷 2131-2133页

作者： Jinxue Wei Yu Wang Zijian Zhang Xiao Yang Liansheng Zhao Peiyan Ni Rongjun Ni Xiaohong Ma Mental Health Center and Psychiatric Laboratory West China Hospital of Sichuan UniversityChengduSichuan 610041China

To the Editor:Major depressive disorder(MDD)is a common mood disorder that contributes considerably to disability worldwide.Abnormalities in either structural connectivity or functional connectivity in the brains of p... 详细信息

关键词： structural connectivity functional