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Chemical Research in Chinese Universities 2005年第3期21卷 326-333页

作者： YANGKe-er tongshan-ling YANYan KANGEn-hua XIAOFeng-shou LIQing CHANGXin FANGChi-guang DepartmentofChemistry InstituteofAdrancedMaterialsShantouUniversityShantou515063ChinaP.R. CollegeofChemistry JilinUniversityChangchun130023ChinaP.R. TheSanitationCenterofInspection＆TestofJilinProvince Changchun130012P.R.China

In an alkaline 2-propanol solution with 5,10,15,20-tetra(4-methoxyl phenyl) porphyrin iron chloride(TOMPPFeCl) as a catalyst and oxygen as a cheap green oxidant, 2-naphthol was conversed to 2-hydroxy-\{1,4-naphthoquinone(HNQ)\} with a yield of 62.17% and a selectivity of 100%, and the conversion number of TMOPPFeCl catalyst was 8.32/min. The catalytic oxidation products were characterized by means of UV-Vis, IR, GC-MS, ~ 1H NMR and melting point determination. In this catalytic oxidation, the catalytic activity of TMOPPFeCl was researched in detail and the reacting conditions were optimized. A possible reaction mechanism is summarized based on in situ EPR determination.

关键词： Catalytic oxidation Naphthol 2-Hydroxy-1,4-naphthoquinone Molecular oxygen Metalloporphyrin catalyst 2-Propanol

Kinetic Studies on Interactions of Ferreous-porphyrins with Hydrogen Peroxide

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Chemical Research in Chinese Universities 2004年第5期20卷 594-597页

作者： YANYan JIANWen-ping GUOHong-wei YANGKe-er tongshan-ling FANGChi-guang LIQing CHANGXin XIAOFeng-shou DepartmentofChemistry ShantouUniversityShantou515063P.R.China CollegeofChemistry JilinUniversityChangchun130023P.R.China TheSanitationCenterofInspection＆TestofJilinProvince Changchun130012P.R.China

In an alkali-methanol solution, both 1- and 2-naphthol can be converted into 2-hydroxy-1,4-naphthoquinone(HNQ) with selectivity more than 95% by H_2O_2 over metalloporphyrin catalyst. The UV-Vis spectra indicate that a high valence oxygen-ferreous porphyrin intermediate has been produced by addition of an aqueous solution of H_2O_2 into the catalytic system. This intermediate formation rate is influenced by the concentrations of low valence ferrous porphyrin, H_2O_2, and NaOH existing in the system. With the aid of the UV-Vis spectrum varieties, the rate equations and formation rate constants of the intermediate at different temperatures can be determined by changing the original concentration of each reactant. The formation activation energy of this intermediate was also determined by changing temperature.

关键词： Ferrous porphyrin catalyst Intermediate Kinetics

Dynamic recrystallization mechanism, texture evolution development and mechanical characteristics of a Mg–8.7Gd–4.18Y–0.42Zr magnesium alloy by ECAP

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Progress in Natural Science:Materials International 2024年第02期34卷 376-388页

作者： ling Zhang Yinglong Li School of Materials Science and Engineering Northeastern University School of Mechanical and Engineering Ningxia Institute of Science and Technology

Equal channel angle pressing is recognized for its ability to refine alloy grains and alter grain orientation, thereby achieve better mechanical performance of the magnesium alloy. This study investigates the microstructures,dynamic recrystallization mechanism, texture development, and mechanical performance of GW94K(Mg–8.7Gd–4.18Y–0.42Zr wt. %) Mg alloy following ECAP-4 passes at 400°C and 3 mm/min. Results show that when high-temperature deformation is undertaken, twin formation is suppressed while dislocation slip is facilitated, increasing dislocation density during deformation. Following ECAP deformation, the sample displayed higher fracture elongation, TYS, and UTS than the as-solutioned GW94K alloy. In particular, the GW94K alloy performed well mechanically after ECAP-4 passes, with an ultimate TYS of 231 MPa, an UTS of 290 MPa, and an elongation of 14.8 %. DDRX and shear bands induce CDRX, both of which are important in plastic deformation. as well as in modifying microstructure and grain orientation during ECAP deformation.

关键词： Dynamic recrystallization mechanism Equal channel angular pressing Magnesium alloy Mechanical performance Mg-Gd-Y-Zr alloy Texture development

加州大学的卓越发展路径——兼谈加州大学伯克利分校世界一流大学的建设

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中国高教研究 2024年第4期 55-63页

作者：常桐善西安欧亚学院教育创新研究院陕西西安710065 加州大学校长办公室院奥克兰94607

加州大学的兴起是20世纪全球高等教育发展史上的辉煌成就,其伯克利分校是多年来全球公认的顶尖公立大学。加州大学的成功有“天时地利人和”的因素,但更重要的原因是其崇尚追求科学、致力于创新、服务社会的大学精神和内部卓越的治理体... 详细信息

加州大学的兴起是20世纪全球高等教育发展史上的辉煌成就,其伯克利分校是多年来全球公认的顶尖公立大学。加州大学的成功有“天时地利人和”的因素,但更重要的原因是其崇尚追求科学、致力于创新、服务社会的大学精神和内部卓越的治理体系。其治理体系的特征包括通过职业化的行政领导力和专业化的学术领导力提升大学治理效能;倾尽所能多渠道筹措经费,确保高质量办学资源;引进卓越教师,并赋能他们的创新研究和教学工作;将理论与实践紧密结合,丰富学生就读经历,担当培养未来科学家和领导者的使命;通过实施问题导向性的学科评估,不断改进质量。当然,联邦政府的政策影响,加州人口结构的变化和经费拮据以及高等教育的国际竞争加剧等因素将持续影响加州大学及其伯克利分校的长远发展。

关键词：加州大学加州大学伯克利分校高等教育世界一流大学

Eigenvalues for the Clamped Plate Problem of L_(ν)^(2) Operator on Complete Riemannian Manifolds

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Acta Mathematica Sinica,English Series 2024年第9期40卷 2223-2243页

作者： ling Zhong ZENG Jiangxi Provincial Center for Applied Mathematics&School of Mathematics and Statistics Jiangxi Normal UniversityNanchang 330022P.R.China

L_(ν) operator is an important extrinsic differential operator of divergence type and has profound geometric *** this paper,we consider the clamped plate problem of L_(ν)^(2)operator on a bounded domain of the complete Riemannian manifolds.A general formula of eigenvalues of L_(ν)^(2) operator is *** this general formula,we obtain some estimates for the eigenvalues with higher order on the complete Riemannian *** several fascinating applications,we discuss this eigenvalue problem on the complete translating solitons,minimal submanifolds on the Euclidean space,submanifolds on the unit sphere and projective *** particular,we get a universal inequality with respect to the L_(II) operator on the translating ***,it is very difficult to get universal inequalities for weighted Laplacian and even Laplacian on the complete Riemannian ***,this work can be viewed as a new contribution to universal estimate.

关键词： Mean curvature flows L_(ν)^(2)operator clamped plate problem eigenvalues Riemannian manifolds translating solitons

MODIFIED STOCHASTIC EXTRAGRADIENT METHODS FOR STOCHASTIC VARIATIONAL INEQUALITY

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Journal of Computational Mathematics 2024年第2期42卷 390-414页

作者： ling Zhang lingling Xu School of Management and Economic Beijing Institute of TechnologyBeijing 100081China School of Mathematical Sciences Nanjing Normal UniversityNanjing 210023China School of Mathematical Sciences and Jiangsu Key Laboratory for NSLSCS Nanjing Normal UniversityNanjing 210023China

In this paper,we consider two kinds of extragradient methods to solve the pseudo-monotone stochastic variational inequality ***,we present the modified stochastic extragradient method with constant step-size(MSEGMC)and prove the convergence of *** the strong pseudo-monotone operator and the exponentially growing sample sequences,we establish the R-linear convergence rate in terms of the mean natural residual and the oracle complexity O(1/ǫ).Second,we propose a modified stochastic extragradient method with adaptive step-size(MSEGMA).In addition,the step-size of MSEGMA does not depend on the Lipschitz constant and without any line-search ***,we use some numerical experiments to verify the effectiveness of the two algorithms.

关键词： Stochastic variational inequality Pseudo-monotone Modified stochastic ex-tragradient methods Adaptive step-size

Space telescope set to open a new chapter in China's solar research

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National Science Review 2024年第1期11卷 225-227页

作者： ling Xin 机构不祥

One year after China launched its first dedicated space telescope to study the Sun, the Advanced Space-based Solar Observatory(ASO-S) is now fine-tuned and ready for discoveries during the activity peak of this solar cycle. ‘ASO-S has completed its in-orbit tests, and all instruments are in stable operation. Some early results are already in the pipeline,’ said the mission’s chief scientist, Gan Weiqun, as the telescope was officially delivered to his co-workers at the Purple Mountain Observatories,

关键词：

Structural engineered living materials

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Nano Research 2024年第2期17卷 715-733页

作者： Yang Geng Zian Jia ling Li 635 Prices Fork Road Department of Mechanical EngineeringVirginia Polytechnic Institute and State UniversityBlacksburg VA24061USA

Biological structural materials not only exhibit remarkable mechanical properties but also often embody dynamic characteristics such as environmental responsiveness,autonomy,and self-healing,which are difficult to achieve in conventional engineering *** merging materials science,synthetic biology,and other disciplines,engineered living materials(ELMs)provide a promising solution to combine living organisms with abiotic components,thus facilitating the construction of functional“living”*** natural materials,ELMs possess vitality and hold immense application potential in areas such as medicine,electronics,and construction,captivating increasing research attention *** an emerging branch of ELMs,structural ELMs aim to mimic living biological structural materials by achieving desired mechanical performance while maintaining important“living”*** we summarize the recent progress and provide our perspectives for this emerging research *** first summarize the superiority of structural ELMs by reviewing biological structural materials and biomimetic material design ***,we provide a systematic discussion on the definition and classifications of structural ELMs,their mechanical performance,and physiological ***,we summarize some critical challenges faced by structural ELMs and highlight directions of future *** hope this review article can provide a timely summary of the state of the art and relevant perspectives for future development of structural ELMs.

关键词： structural materials engineered living materials(ELMs) structural ELMs composites mechanical properties

A Graded Speed Control Method for Cyborg Rats Based on Electrical Stimulation of the Cuneiform Nucleus

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Journal of Bionic Engineering 2024年第3期21卷 1334-1346页

作者： Hanyi ling Le Han Nenggan Zheng Qiushi Academy for Advanced Studies(QAAS) Zhejiang UniversityHangzhou310007China The State Key Lab of Brain-Machine Intelligence Zhejiang UniversityHangzhou310007China College of Biomedical Engineering&Instrument Science Zhejiang UniversityHangzhou310007China College of Computer Science and Technology Zhejiang UniversityHangzhou310007China CCAI by MOE and Zhejiang Provincial Government(ZJU) Hangzhou310007China

The precise movement speed regulation is a key factor to improve the control effect and efficiency of the cyborg ***,the current stimulation techniques cannot realize the graded control of the *** this study,we achieved the multi-level speed regulation of cyborg rats in the large open field and treadmill by specifically targeting the Cuneiform Nucleus(CnF)of the Mesencephalic Locomotor Region(MLR).Detailed,we measured the influence of each stimulation parameter on the speed control process which included the real-time speed,accelerated speed,response time,and acceleration *** concluded that the pulse period and the pulse width were the main determinants influencing the accelerated speed of cyborg *** the amplitude of stimulation was found to affect the response time exhibited by the cyborg *** study provides valuable insights into the regulation of rat locomotion speed and highlights the potential for utilizing this approach in various experimental settings.

关键词： Cyborg rats Cuneiform nucleus Graded control Speed regulation

Lewis Base Catalyzed Selenofunctionalization of Alkynes with Acid-Controlled Divergent Chemoselectivity

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Chinese Journal of Chemistry 2024年第14期42卷 1623-1629页

作者： ling-ling Chen Ren-Fei Cao Hua Ke Zhi-Min Chen School of Chemistry and Chemical Engineering Shanghai Key Laboratory for Molecular Engineering of Chiral DrugsShanghai Jiao Tong UniversityShanghai200240 China Engineering Technology Research Center for Environmental Protection Materials Pingxiang UniversityPingxiangJiangxi337055 China

Lewis base catalyzed and Brønsted acid controlled chemodivergent electrophilic selenofunctionalizations of alkynes were developed for the first *** selenium-containing tetrasubstituted alkenes were readily obtained in moderate to excellent yields with complete E/Z *** the substrates were 1-ethynyl naphthol derivatives,linear selenium-containing tetrasubstituted alkenes were produced via intermolecular oxygen nucleophilic attack in the absence of acid additive;in contrast,cyclic selenium-containing tetrasubstituted alkenes were generated through intramolecular carbon nucleophilic capture with the addition of Brønsted acid.

关键词： Alkynes Electrophilic addition Chemoselectivity Lewis base catalysis Selenofunctionalization