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Enantioselective Synthesis of cis-2,6-Disubstituted-4-methylene Tetrahy-dropyrans via Chromium Catalysis

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Chinese Journal of Chemistry 2020年第12期38卷 1642-1646页

作者： Jing bai bin Chen Guozhu Zhang State Key Laboratory of organometallic Chemistry Center for Excellence in Molecular Synthesis Shanghailnstitute of Organic ChemistryUniversty of Chinese Academy of SciencesChinese Academy of Sciences345 Lingling RoodShanghai 200032China

of main observation and conclusion Enantioenriched 2,6-disubstituted 4-methylene tetrahydropyrans have been obtained via a two-step sequence consisting of a highly enantioselective chromium-catalyzed carbonyl 2-(trimethylsilyl methyl)allylation and Prins *** available(2-(chloromethyl)allyl)trimethylsilane serves as the bifunctional linchpin to combine two aldehydes to assemble the 2,6-disubstituted pyrans.A variety of functional groups are compatible under the mild reaction *** synthetic utility of this methodology was demonstrated by the asymmetric synthesis of 16 examples of homoallylic alcohol and 8 examples of 2,6-disubstituted 4-methylene tetrahydropyrans,including an advanced intermediate which could be transformed to natural product centrolobine via a known procedure.

关键词： substituted methylene allyl

Generation of Plvap-CreER and Car4-CreER for genetic targeting of distinct lung capillary populations

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Journal of Genetics and Genomics 2022年第12期49卷 1093-1100页

作者： Zhenqian Zhang bin zhou State Key Laboratory of Cell Biology Shanghai Institute of Biochemistry and Cell BiologyCenter for Excellence in Molecular Cell ScienceChinese Academy of SciencesUniversity of Chinese Academy of SciencesShanghai 200031China Key Laboratory of Systems Health Science of Zhejiang Province School of Life ScienceHangzhou Institute for Advanced StudyUniversity of Chinese Academy of SciencesHangzhouZhejiang 310024China School of Life Science and Technology Shanghai Tech UniversityShanghai 201210China

It has been reported recently that there are two distinct subpopulations of capillary endothelial cells in the mammalian lungs:gCap(general capillary)and aCap(aerocyte).They are identified by two unique markers,respectively:plasmalemmal vesicle-associated protein(PLVAP)and carbonic anhydrase IV(CAR4).Here,we report two novel knock-in mouse lines Plvap-CreER and Car4-CreER,which genetically target gCap and aCap,*** by tamoxifen,the Plvap-CreER and Car4-CreER alleles mediate specific and efficient Cre-loxP recombinations in PLVAP+gCap and CAR4+aCap,respectively,in the *** two mouse lines are useful genetic tools to investigate cell fates and functions of PLVAP+and CAR4+cells in lung homeostasis,injury and repair.

关键词： lung homeostasis capillary

High-rate lithium-ion battery performance of a ternary sea urchin-shaped CoNiO_(2)@NiP_(6)Mo_(18)/CNTs composites

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Journal of Energy Chemistry 2024年第9期96卷 516-525页

作者： Li-ping Cui Shuang Sun Kai Yu Shu Zhang Mei-lin Wang Jia-jia Chen bai-bin zhou Key Laboratory for Photonic and Electronic Bandgap Materials Ministry of EducationSchool of Chemistry and Chemical EngineeringHarbin Normal UniversityHarbin 150025HeilongjiangChina State Key Laboratory of Physical Chemistry of Solid Surfaces Department of ChemistryCollege of Chemistry and Chemical EngineeringCollaborative Innovation Centre of Chemistry for Energy MaterialsXiamen UniversityXiamen 361005FujianChina

Bimetallic oxides are attractive anode materials for lithium-ion batteries(LIBs)due to their large theoretical ***,the low conductivity,short cycle life,and poor rate capability are the bottlenecks for their further *** overcome above issues,the basket-like polymolybdate(NiP_(6)Mo_(18))and carbon nanotubes(CNTs)were uniformly embedded on the urchin-shaped CoNiO_(2)nanospheres to yield a ternary composites CoNiO_(2)@NiP_(6)Mo_(18)/CNTs via electrostatic *** multi-level morphology of urchin spinules accelerates the diffusion rate of Li^(+);CNT improves the conductivity and enhances cycle stability of the material;and heteropoly acid contributes more redox activity ***,CoNiO_(2)@NiP_(6)Mo_(18)/CNTs as an anode of LIBs exhibits a high initial capacity(1396.7 mA h g^(−1)at 0.1 A g^(−1)),long-term cycling stability(750.2 mA h g^(−1)after 300 cycles),and rate performance(450.3 mA h g^(−1)at 2 A g^(−1)),which are superior to reported metallic oxides anode of *** density functional theory(DFT)and kinetic mechanism suggest that CoNiO_(2)@NiP_(6)Mo_(18)/CNTs delivers an outstanding pseudocapacitance and rapid Li^(+)diffusion behaviors,which is due to the rich surface area of the urchin-like CoNiO_(2)with the uniform embeddedness of NiP_(6)Mo_(18)and *** study provides a new idea for optimizing the performance of bimetallic oxides and developing high-rate lithium-ion battery composites.

关键词： Bi-metal oxides Transition metal oxides Polyoxometalates Nanocomposite LIBs

Discontinuous deformation and displacement analysis: From continuous to discontinuous

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Science China(Technological Sciences) 2015年第9期58卷 1567-1574页

作者： TANG ChunAn TANG Shibin GONG bin bai HongMei State Key Laboratory of Coastal and Offshore Engineering Dalian University of Technology Dalian Mechsoft Co. Ltd.

A discontinuous deformation and displacement(DDD) analysis method is proposed for modelling the rock failure process. This method combines the rock failure process analysis(RFPA) method(based on finite element method) and discontinuous deformation analysis(DDA) method. RFPA is used to simulate crack initiation, propagation and coalescence processes of rock during the small deformation state. The DDA method is used to simulate the movement of blocks created by the multiple cracks modelled by the RFPA. The newly developed DDD method is particularly suitable for modelling both crack propagation and block movement during the rock failure process because of the natural and convenient coupling of continuous and discontinuous deformation analyses. The proposed method has been used to simulate crack initiation, propagation and coalescence within a slope as well as the block movement during the landslide process. Numerical modelling results indicate that the proposed DDD method can automatically simulate crack propagation and block movement during the rock failure process without degrading accuracy.

关键词： rock failure process finite element method discontinuous deformation analysis (DDA) crack propagation slope stability

Semiempirical equations of state of H_(2)O/CO_(2) binary mixtures in graphite nanoslits

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Science China(Physics,Mechanics & Astronomy) 2023年第8期66卷 83-92页

作者： Haoxuan Li bin Zhao Chengzhen Sun Bofeng bai State Key Laboratory of Multiphase Flow in Power Engineering Xi'an Jiaotong UniversityXi'an 710049China

The existence of confining walls limits the prediction accuracy of nanoconfined fluids using macroscopic equations of state(EOSs);moreover,appropriate EOSs for multicomponent mixture fluids in nanoconfined spaces are ***,we derive the EOS of multicomponent mixture fluids confined in nanospaces at high temperatures and pressures,mainly considering the nanoconfinement effect and the competitive adsorption effect between different ***,the EOSs are validated through comparison with the molecular dynamics-simulated Pv T data of CO_(2)/H_(2)O mixtures in graphite *** consider the above effects,we derive two EOSs via two modeling methods:EOS I is obtained through modification of the actual component occupation volume in the Peng-Robinson equation of state(PR EOS)by fitting the binary component interaction coefficient and the number of adsorbed molecules according to a selectivity coefficient,while EOS II is obtained by considering the decreased pressure of the fluids in PR EOS by adding an attractive term between components and *** the simulation results as a benchmark,the two EOSs exhibited good prediction accuracies under low CO_(2) concentrations,and generally,EOS II was more accurate than EOS *** study fills the gap in the EOSs of nanoconfined mixture fluids,and the obtained equations can help to further describe the thermodynamic properties of confined mixture fluids.

关键词： confined fluid mixtures equation of state nanoconfined spaces molecular dynamics simulation

Natural products are the treasure pool for antimalarial agents

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National Science Review 2022年第11期9卷 11-13页

作者： bin zhou Jian-Min Yue State Key Laboratory of Drug Research Shanghai Institute of Materia Medica Chinese Academy of Sciences

The history of mankind is a constant struggle against diseases, and humans have learned to use natural sources as the remedies to alleviate and/or treat diseases since prehistoric times.e structural diversity and complexity of molecules originated from natural sources are far beyond the scope of human creativity and imagination.

关键词：

Scalable fabrication of Bi_(2)O_(2)Se polycrystalline thin film for near-infrared optoelectronic devices applications

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Chinese Physics B 2021年第10期30卷 470-475页

作者： bin Liu Hong zhou School of Physics and Electronics Hunan UniversityChangsha 410082China

We present a controlled,stepwise formation of layered semiconductor Bi_(2)O_(2)Se thin films prepared via the vapour process by annealing topological insulator Bi_(2)Se3 thin films in low oxygen atmosphere for different *** based on Bi_(2)O_(2)Se thin film show a responsivity of 1.7×10^(4) A/W at a wavelength of 980 ***-effect transistors based on Bi_(2)O_(2)Se thin film exhibit n-type behavior and present a high electron mobility of 17 cm^(2)/V·*** addition,the electrical properties of the devices after 4 months keeping in the air shows little change,implying outstanding air-stability of our Bi_(2)O_(2)Se thin *** the obtained results,it is evident that low oxygen annealing is a surprisingly effective method to fabricate Bi_(2)O_(2)Se thin films for integrated optoelectronic applications.

关键词： thin films Bi_(2)Se_(3) vapor-phase deposition photodetector Bi_(2)O_(2)Se

Characteristics of SEN clogging and adhesive behavior of oxide inclusion during continuous casting of Ti-stabilized ultra-pure ferritic stainless steels

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Journal of Iron and Steel Research International 2023年第10期30卷 1939-1951页

作者： Xue-feng bai Yan-hui Sun Hui-bin Wu Collaborative Innovation Center of Steel Technology University of Science and Technology BeijingBeijing100083China

Submerged entry nozzle(SEN)clogging during continuous casting of Ti-stabilized ultra-pure ferritic stainless(Ti-UPFS)steels was systematically investigated via cross-sectional analysis and acid dissolution *** SEN deposit profile was characterized as occurring in three major layers:(1)an eroded refractory layer;(2)an initial adhesive layer comprised an Al_(2)O_(3)-ZrO_(2) composite sub-layer and a dense Al_(2)O_(3)-based deposit sub-layer;and(3)a porous multiphase deposit layer mainly consisting of MgO·Al_(2)O_(3),CaO-Al_(2)O_(3),and *** MgO·Al_(2)O_(3)-rich inclusions did not adhere directly to the eroded refractory but were entrapped during the deposit *** of inclusion characterization in the tundish revealed that the MgO·Al2O3-rich particles present in the tundish served as the primary source of clogging ***,a novel cavity-induced adhesion model by circular approximation was established to explain the effects of complex inclusion characteristics and refractory material type on adhesion force.A high number of small MgO·Al_(2)O_(3) inclusions were expected to accelerate the buildup of clogging *** the modification of MgO·Al_(2)O_(3)-rich inclusions in the size range of 2-4μm by Ca treatment was crucial to minimizing the risk of SEN clogging during the continuous casting of Ti-UPFS steels.

关键词： Ti-stabilized ultra-pure ferritic stainless steel Submerged entry nozzle clogging MgO·Al_(2)O_(3)-rich inclusion Adhesion Continuous casting

主族元素取代的11-钨铜杂多配合物的合成、表征及性质研究

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分子科学学报 2006年第1期22卷 18-23页

作者：王丽丽周百斌张旭马慧媛徐学勤韦永德哈尔滨师范大学化学系黑龙江哈尔滨150080 哈尔滨工业大学应用化学系黑龙江哈尔滨150001

合成了ⅡA,ⅣA,ⅤA族元素为取代原子的3个系列钨铜杂多配合物.经ICP,TG曲线确定其化学式为K8[CuZ(OH2)W11O39].xH2O和K17,18[Z′(CuW11O39)2].xH2O(Z=Mg,Ca;Z′=Sr,Ba,Sn,Pb,Sb,Bi).通过TG-DTA,IR,XRD,XPS,183W-NMR等手段对合成配合物结构进行了表征,并对其进行了讨论.结果表明,新配合物具有典型的Keggin结构,且主族元素进入到配合物的骨架中.由于新配合物中CuⅡ具有顺磁性,导致XPS,183W-NMR的测试结果表现出特殊性;用循环伏安法测定了新配合物的电化学性质,表明均为可逆氧化还原过程,还对导电性和热稳定性进行了研究.

关键词：主族元素杂多配合物电化学性质导电性