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DFT Study on the Structure and Racemization Mechanism of 1,1 ＇- Bina phthalene-8,8 ＇-diol

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Chinese Journal of Chemical Physics 2008年第4期21卷 367-375页

作者： Liang-guo Da tong-tong lu Mei Xiang Tian-jing He Dong-ming Chen Department of Chemical Physics University of Science and Technology of China Hefei 230025 China Department of Chemical Biology Huainan Normal University Huainan 232001 China

Density functional theory （DFT） was applied to study the ground state geometries and isomerization processes of 1,1＇-binaphthalene-8,8＇-diol. Three isomers, denoted as ISO1, ISO2, and ISO3, were found, distinguished by different orientations of the OH groups, and each OH-orientational isomer has R- and S-enantiomer. The conformational stabilities of these isomers were investigated by tracking the energy change with respect to the ring-to-ring torsion. The inter-conversions between the three OH-orientational S-isomers were found to have quite low barriers owing to the nearly free rotation of OH groups around the O-C single bonds. The S-R enantiomerization of ISO1 and ISO2 can take place through the ring-ring torsion around the C1-C1/ single bond, either in the anti-rotation manner or in the syn-rotation manner. The barriers of the anti routes are lower than those of the corresponding syn routes by 87.95 and 75.04 kJ/mol. For the S-R enantiomerization of ISO3, only the anti route was found. The barriers for the anti route enantiomerizations of ISO1, ISO2, and ISO3 are 119.61, 120.43, and 121.59 kJ/mol, respectively. A parallel reaction mechanism via three anti enantiomerization routes was proposed for the racemization of 1,1＇-binaphthalene-8,8＇-diol.

关键词： Density functional theory (DFT) 1 1'-Binaphthalene-8 8'-diol Racemization

Metal-organic frameworks with dinuclear metal centers for synergistically boosting CO2 photoreduction

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Science China Chemistry 2025年第1期68卷 201-208页

作者： Hui-Feng Wang Wen-Jie Shi Yu-Xin Yang Bao-Xia Dong tong-Bu lu Di-Chang Zhong School of Chemistry and Chemical Engineering Yangzhou University Institute for New Energy Materials and Low Carbon Technologies School of Materials Science and Engineering Tianjin University of Technology

Dinuclear metal synergistic catalysis （DMSC） has been proved powerful in boosting CO2reduction,while this has not been achieved in heterogeneous catalysts with long-range order *** this study,we,by introduction of metal catalytic centers into an indium-based metal-organic framework （MOF）,obtained a series of isostructural In-MOFs,including three MOFs with mononuclear metal catalytic center （M-In）,three MOFs with dinuclear homometallic catalytic centers （MM-In）,and three MOFs with dinuclear heterometallic catalytic centers (MM’-In,M/M’=Co（II）,Ni（II）,Zn（II）).It was found that all these MOFs can serve as catalysts for photochemical CO2reduction to *** with M-In,the catalytic activities of MM-In were obviously enhanced,and that of MM’-In was further significantly *** example,the CO yield of Co Zn-In reaches a record value of 12,700μmol g-1h-1,which is 4.0,8.1,9.4,and 18.6-fold higher than that of Co Co-In,Zn Zn-In,Co-In,and Zn-In,***,the catalytic activities of Co Ni-In and Ni Zn-In also show different fold increase than those of corresponding dinuclear homometallic and mononuclear metallic *** results of control experiments and theoretical calculation reveal that the higher catalytic activities of MM-In over M-In can be ascribed to the DMSC effect,and the higher catalytic activity of MM’-In over MM-In can be ascribed to the strengthened DMSC *** work reveals the relationship between DMSC effect and bimetal centers in CO2reduction,which provides new insights into the DMSC and paves a new way to design highly active catalysts for photochemical CO2reduction.

关键词： metal-organic frameworks dinuclear metal centers synergistic catalysis CO2 reduction photocatalysis

Microspheres trigged-stress concentration regulating piezoelectric properties of PVDF/elastomer composites

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Science China Chemistry 2025年

作者： Wenxian Zhang Jiahong Yang Qijun Sun lu Peng tong Lin Shouke Yan Xiaoli Sun State Key Laboratory of Chemical Resource Engineering Beijing University of Chemical Technology Beijing Institute of Nanoenergy and Nanosystems Chinese Academy of Sciences State Key Laboratory of Separation Membranes and Membrane Processes School of Textile Science and EngineeringTiangong University Key Laboratory of Rubber-Plastics of Ministry of Education Shandong Provincial Key Laboratory of Rubber-PlasticsQingdao University of Science & Technology

Wearable self-powered piezoelectric pressure sensors are attracting tremendous ***,fabricating a high-sensitive elastic piezoelectric sensor for a broad response range remains ***,we assemble polar poly（vinylidene fluoride）(PVDF) microsphere-elastomer composites,achieving high-sensitive and wide-responsive pressure *** polar PVDF microspheres are produced cost-effectively through phase separation,enabling *** piezoelectric composite （PC） film demonstrates low Young’s modulus,and excellent anti-fatigue ***,the PC-based piezoelectric sensor exhibits a rather high sensitivity of 540 mV N-1in a wide sensing range （5–40 N）,240 times greater than the PVDF film-based sensor and comparable to the inorganic piezoelectric *** excellent performance is attributed to the highest average stress concentration on the spherical PVDF coupled with the remarkable deformation of dipoles of spherical PVDF in the flexible *** on excellent performance,this piezoelectric sensor achieves precise recognition of motions and sound *** high-sensitive flexible piezoelectric sensor enabling large area production with ultralow price exerts great potential in smart monitoring and intelligent robots.

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Vibrational Spectra and Density Functional Theory Calculations of Metallo-tetra- （tert-butyl）-tetra-azaporphyrines

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Chinese Journal of Chemical Physics 2010年第5期23卷 573-581,622页

作者：卢同同高慧玲何天敬刘凡镇陈东明中国科学技术大学化学物理系合肥230026

The infrared absorption and 514.5 nm excited Raman spectra were measured for the metallo- tetra-（tert-butyl）-tetraazaporphyrin （MT（tBu）TAP, M--Cu, Co, Ni, Zn）. The ground-state structures and vibrational spectra of MT（tBu）TAPs have been calculated at the B3LYP level of theory. The observed Raman and IR bands have been assigned based on the calculation results and by comparing with the normal metalloporphyrins. The relationship between the Raman/IR frequencies and the structures of TAP ring was investigated. The results show that the frequencies of CβCβ′ stretch （Ag）, asymmetric CaNto stretch （Ag）, and symmetric CaNto stretch （Bg） modes increase linearly with the decrease of the core-sizes of TAP ring. Among the three modes, the later two are more sensitive to the core-size change.

关键词： Tetraazaporphyrin Raman spectrum Molecular vibration Density functional theory

A novel flexible nerve guidance conduit promotes nerve regeneration while providing excellent mechanical properties

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Neural Regeneration Research 2025年第7期20卷 2084-2094页

作者： tong Li Quhan Cheng Jingai Zhang Boxin Liu Yu Shi Haoxue Wang Lijie Huang Su Zhang Ruixin Zhang Song Wang Guangxu lu Peifu Tang Zhongyang Liu Kai Wang Department of Orthopedics the Fourth Medical Center of Chinese PLA General HospitalBeijingChina Department of Training and Sports Medicine Characteristic Medical Center of Chinese People’s Armed Police ForceTianjinChina Medical School of Chinese PLA BeijingChina Key Laboratory of Bioactive Materials for the Ministry of Education College of Life SciencesNankai UniversityTianjinChina Department of Orthopedics Tianjin HospitalTianjinChina Department of Rehabilitation Medicine Er Quan Hospital of PAPWuxiJiangsu ProvinceChina

Autografting is the gold standard for surgical repair of nerve defects>5 mm in length;however,autografting is associated with potential complications at the nerve donor *** an alternative,nerve guidance conduits may be *** ideal conduit should be flexible,resistant to kinks and lumen collapse,and provide physical cues to guide nerve *** designed a novel flexible conduit using electrospinning technology to create fibers on the innermost surface of the nerve guidance conduit and employed melt spinning to align ***,we prepared disordered electrospun fibers outside the aligned fibers and helical melt-spun fibers on the outer wall of the electrospun fiber *** presence of aligned fibers on the inner surface can promote the extension of nerve cells along the *** helical melt-spun fibers on the outer surface can enhance resistance to kinking and compression and provide *** novel conduit promoted nerve regeneration and functional recovery in a rat sciatic nerve defect model,suggesting that it has potential for clinical use in human nerve injuries.

关键词： aligned fibers anti-kinking helical fibers nerve guidance conduit nerve regeneration peripheral nerve injury topological guidance

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母血中分离检测胎儿细胞的研究进展

实用妇产科杂志 2000年第5期16卷 239-241页

作者：郑彤彤吕时铭三门县人民医院浙江三门317100 浙江大学医学院附属妇产科医院浙江杭州310006

进入母体血循环的胎儿细胞有 4种。使用有效的方法从正常与异常妊娠母血中分离富集极少量的胎儿有核红细胞、滋养细胞、淋巴细胞和粒细胞。目前国外采用较多的有荧光激活细胞分选法、磁活化细胞分选法、免疫磁珠分离法、密度梯度离心法... 详细信息

进入母体血循环的胎儿细胞有 4种。使用有效的方法从正常与异常妊娠母血中分离富集极少量的胎儿有核红细胞、滋养细胞、淋巴细胞和粒细胞。目前国外采用较多的有荧光激活细胞分选法、磁活化细胞分选法、免疫磁珠分离法、密度梯度离心法。分子生物学方法的引入。特别是聚合酶链反应及其衍生技术和荧光原位杂交技术提供了从母血中检测胎儿细胞敏感的方法并在无创伤性产前诊断方面得到一定的应用。

关键词：胎和细胞母血富集纯化产前诊断研究进展

Understanding the local structure and thermophysical behavior of Mg-La liquid alloys via machine learning potential

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International Journal of Minerals,Metallurgy and Materials 2025年第2期32卷 439-449页

作者： Jia Zhao Taixi Feng Guimin lu National Engineering Research Center for Integrated Utilization of Salt Lake Resource East China University of Science and TechnologyShanghai 200237China Joint International Laboratory for Potassium and Lithium Strategic Resources East China University of Science and TechnologyShanghai 200237China

The local structure and thermophysical behavior of Mg-La liquid alloys were in-depth understood using deep potential molecular dynamic(DPMD) simulation driven via machine learning to promote the development of Mg-La alloys. The robustness of the trained deep potential(DP) model was thoroughly evaluated through several aspects, including root-mean-square errors(RMSEs), energy and force data, and structural information comparison results;the results indicate the carefully trained DP model is reliable. The component and temperature dependence of the local structure in the Mg-La liquid alloy was analyzed. The effect of Mg content in the system on the first coordination shell of the atomic pairs is the same as that of temperature. The pre-peak demonstrated in the structure factor indicates the presence of a medium-range ordered structure in the Mg-La liquid alloy, which is particularly pronounced in the 80at% Mg system and disappears at elevated temperatures. The density, self-diffusion coefficient, and shear viscosity for the Mg-La liquid alloy were predicted via DPMD simulation, the evolution patterns with Mg content and temperature were subsequently discussed, and a database was established accordingly. Finally, the mixing enthalpy and elemental activity of the Mg-La liquid alloy at 1200 K were reliably evaluated,which provides new guidance for related studies.

关键词： magnesium-lanthanum liquid alloys local structure macroscopic properties thermodynamic behavior deep potential mo-lecular dynamic simulation

China’s carbon neutrality:an extensive and profound systemic reform

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Frontiers of Environmental Science & Engineering 2023年第2期17卷 1-7页

作者： Xi lu Dan tong Kebin He State Key Joint Laboratory of Environment Simulation and Pollution Control and School of Environment Tsinghua UniversityBeijing 100084China Institute for Carbon Neutrality Tsinghua UniversityBeijing 100084China Beijing Laboratory of Environmental Frontier Technologies Tsinghua UniversityBeijing 100084China State Environmental Protection Key Laboratory of Sources and Control of Air Pollution Complex Beijing 100084China Department of Earth System Science Ministry of Education Key Laboratory for Earth System ModelingInstitute for Global Change StudiesTsinghua UniversityBeijing 100084China

China is the largest developing economy and carbon dioxide emitter in the world,the carbon neutrality goal of which will have a profound influence on the mitigation pathway of global climate *** transition towards a carbon-neutral society is integrated into the construction of ecological civilization in China,and brings profound implications for China’s socioeconomic ***,we not only summarize the major challenges in achieving carbon neutrality in China,but also identify the four potential new opportunities:namely,the acceleration of technology innovations,narrowing regional disparity by reshaping the value of resources,transforming the industrial structure,and co-benefits of pollution and carbon ***,we provide five policy suggestions and highlight the importance of balancing economic growth and carbon mitigation,and the joint efforts among the government,the enterprises,and the residents.

关键词： Carbon neutrality Energy structure Technology-dependent society Coordinated mitigation for air pollutants and CO_(2)

A review of negative electrode materials for electrochemical supercapacitors

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Science China(Technological Sciences) 2015年第11期58卷 1799-1808页

作者： lu XueFeng LI GaoRen tong YeXiang MOE Laboratory of Bioinorganic and Synthetic Chemistry KLGHEI of Environment and Energy ChemistrySchool of Chemistry and Chemical Engineering Sun Yat-sen University

With increasing demands for clean and sustainable energy, the advantages of high power density, high efficiency, and long life expectancy have made supercapacitors one of the major emerging devices for electrochemical energy storage and power supply. However, one of the key challenges for SCs is their limited energy density, which has hindered their wider application in the field of energy storage. Despite significant progress has been achieved in the fabrication of high-energy density positive electrodes materials, negative electrode materials with high capacitance and a wide potential window are relatively less explored. In this review, we introduced some new negative electrode materials except for common carbon-based materials and what's more, based on our team's work recently, we put forward some new strategies to solve their inherent shortcoming as electrode material for SCs.

关键词： supercapacitors negative energy storage review