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Highly Stereoselective Synthesis of 2,2-Disubstituted Vinylphosphonates via Aryl to Vinyl 1,4-Palladium Migration

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Chinese Journal of Chemistry 2022年第18期40卷 2188-2192页

作者： Yan-Zhen Chen Geng-Yu Bao Xin-Chen zhan Jian-guo Fu Xiao-Ming Ji Shu-Sheng zhang Chen-guo feng The Research Center of Chiral Drugs Innovation Research Institute of Traditional Chinese MedicineShanghai University of Traditional Chinese MedicineShanghai201203 China

Vinylphosphates play an important role in the fields of synthetic chemistry,pharmaceuticals and material *** is a long-standing challenge to control the geometry of multi-substituted ***,an efficient method for the synthesis of 2,2-disubstituted vinylphosphonates has been *** reaction proceeded via aryl to vinyl 1,4-palladium migration progress,in which two difficulties that the deactivation of palladium catalyst by the coordination of excess secondary phosphine oxide and the competitive cross-coupling to form arylphosphonates are successfully *** judicious selection of phosphine ligand is the key to *** protocol features excellent regio-and stereoselectivitiy,generally excellent reaction yields and broad substrate socpe.

关键词： 1,4-Palladium migration Phosphorylation C-H activation Stereoselectivity Cross-coupling

Defect-engineered Mn_(3)O_(4)/CNTs composites enhancing reaction kinetics for zinc-ions storage performance

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Journal of Energy Chemistry 2022年第5期31卷 538-547页

作者： Xiuli guo Hao Sun Chunguang Li Siqi zhang Zhenhua Li Xiangyan Hou Xiaobo Chen Jingyao Liu zhan Shi Shouhua feng State Key Laboratory of Inorganic Synthesis and Preparative Chemistry College of ChemistryJilin UniversityChangchun 130012JilinChina Laboratory of Theoretical and Computational Chemistry Institute of Theoretical ChemistryCollege of ChemistryJilin UniversityChangchun 130023JilinChina School of Engineering RMIT UniversityCarltonVIC 3053Australia

The designing of reasonable nanocomposite materials and proper introduction of defect engineering are of great significance for the improvement of the poor electronic conductivity and slow reaction kinetics of manganese-based compounds. Herein, we report manganese-deficient Mn_(3)O_(4) nanoparticles which grow in-situ on highly conductive carbon nanotubes(CNTs)(denoted as DMOC) as an advanced cathode material for aqueous rechargeable zinc-ion batteries(RAZIBs). According to experimental and calculation results, the DMOC cathode integrates the advantages of enriched Mn defects and small particle size. These features not only enhance electronic conductivity but also create more active site and contribute to fast reaction kinetics. Moreover, the structure of DMOC is maintained during the charging and discharging process, thus benefiting for excellent cycle stability. As a result, the DMOC electrode delivers a high specific capacity of 420.6 m A h g^(-1) at 0.1 A g^(-1) and an excellent cycle life of 2800 cycles at 2.0 A g^(-1) with a high-capacity retention of 84.1%. In addition, the soft-packaged battery assembled with DMOC cathode exhibits long cycle life and high energy density of 146.3 Wh kg^(-1) at 1.0 A g^(-1) . The results are beneficial for the development of Zn/Mn_(3)O_(4) battery for practical energy storage.

关键词： Manganese oxide Manganese defects High rate Long cycle life Zinc ion batteries

Rational design of interfacial bonds within dual carbon-protected manganese oxide towards durable aqueous zinc ion battery

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Science China Chemistry 2023年第5期66卷 1406-1416页

作者： Xiuli guo Chunguang Li Xiyang Wang Zhenhua Li Hui Zeng Pan Hou Minggang Xie Yuxin Li zhan Shi Shouhua feng State Key Laboratory of Inorganic Synthesis and Preparative Chemistry College of ChemistryJilin UniversityChangchun 130012China Department of Mechanical and Mechatronics Engineering Waterloo Institute for NanotechnologyMaterials Interface FoundryUniversity of WaterlooWaterlooOntario N2L 3G1Canada

Manganese-based cathode materials are promising candidates for aqueous zinc ion batteries(AZIBs)by reason of their low cost and high energy ***,their practical applicability is hampered by the intrinsic defects of poor electrical conductivity,sluggish reaction kinetics,and severe structural ***,we constructed a hierarchically porous structure composed of carbon-encapsulated Mn O nanoparticles(MOC)and three-dimensional(3D)nitrogen-doped graphene aerogel(NGA)(denoted as MOC@NGA).The hybrid was synthesized by a facile in-situ coprecipitation and annealing of manganesebased metal-organic framework(Mn-MOF74)and NGA composite(Mn-MOF74@NGA).Specifically,the carbon shells inherited from organic ligand of Mn-MOF74 could restrain the volume changes of Mn O,and the porous NGA prevented the agglomeration of MOC nanoparticles and enriched the types of interfacial chemical *** from the synergistic effect of rich interface chemical bonds and dual-carbon protection,the MOC@NGA hybrids exhibit fast interfacial electron/charge transfer and transport,and outstanding structural ***,MOC@NGA cathode delivers an excellent rate performance(270 and 99.8 m Ah g^(-1)at 0.1 and 2.0 A g^(-1))and maintains an excellent specific capacity of 151.6 m Ah g^(-1)after 2,000cycles at 1.0 A g^(-1).Moreover,the fabricated MOC@NGA-based quasi-solid-state battery not only achieves outstanding flexibility but also displays impressive cycling stability,demonstrating a promising potential for portable and flexible *** work provides a feasible strategy for the fabrication of the bridging structure of manganese-based oxides and porous carbon matrix for high-specific capacity and durable AZIBs cathodes.

关键词： manganese oxide interfacial chemical bonds carbon modification aqueous zinc ion batteries

Cell-Cycle-Dependent Variations in the FTIR Spectroscopy of HeLa Cells Treated with Trichostatin A

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光谱学与光谱分析 2011年第8期31卷 2076-2080页

作者： zhanG feng-qiu QI Jian YANG zhan-guo School of Physical Engineering Zhengzhou University Zhengzhou 450052 China

It is quite complex to evaluate the mechanism of action for antitumor drugs on cancer *** have pointed out that there is an unique advantage of Fourier transform infrared spectrum to obtain a fingerprint of all molecules present in the cells when cancer cells were exposed to anti-cancer *** A(TSA) is a most potent reversible inhibitor of mammalian histone *** can inhibit cancer cell growth in vitro and in *** the present study,HeLa cells were exposed to 0,50,100,200,300 and 400 nmol·L-1 TSA,and FTIR spectra were applied to evaluate the effect of TSA on cancer *** show that there is some significant relationship between the changes in FTIR absorption and cell cycle *** the other hand,this investigation shows that the concentration of TSA had to be more than 200 nmol·L-1 in order to ensure A1 080 cm-1/A1 540 cm-1≥1 for inhibiting cell proliferation.

关键词： Fourier transform infrared spectrum Trichostatin A Cell cycle

Rate allocation strategies for energy-efficient multipath routing in Ad-hoc networks towards B3G

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The Journal of China Universities of Posts and Telecommunications 2007年第2期14卷 84-88页

作者： zhan Song-tao XU guo-xin Wireless Technologies Innovation Institute Key Laboratory of Universal Wireless Communication Ministry of Education Beijing University of Posts and Telecommunications Beijing 100876 China

Wireless mobile Ad-hoc network is a special network that all nodes can serf-organize and work together. It is flexible to form a network and extend the coverage area dynamically without infrastructure, so Ad-hoc network is envisioned as cornerstones of future generation networking technologies （B3G or 4（3）. However, the dynamic network topology makes the communication cost not only the energy of source/destination nodes, but also the relay nodes. Another problem of the Ad-hoc network is it is hard to provide a stable and persistent quality of service （QoS）, which is strongly required by the beyond 3rd generation （B3G） system. In this article, the authors establish a scenario that contains B3G cellular base station and Ad-hoc mobile nodes, and propose two algorithms minimum incremental rate algorithm and power feed-back rate allocation algorithm in multipath routing. The algorithms can maintain a constant total transmission rate and bit error ratio （BER） to provide the QoS guarantee and reach the minimum power consumption of the relay nodes by adjusting the rate of each path in the multipath routing.

关键词： Ad-hoc network B3G multipath routing energy consumption QoS

CRYSTALLIZATION OF AMORPHOUS Fe_(62)Co_(15.5)Nd_(4)B_(18.5) ALLOY AND ITS INFLUENCE ON HARD MAGNETIC PROPERTIES

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Chinese Physics Letters 1990年第9期7卷 429-432页

作者： SHEN Baogen YANG Linyuan zhanG Junxian WO feng NING Taishan ZHAO Jiangao guo Huiqun zhan Wenshan Magnetism Laboratory Institute of PhysicsAcademia SinicaBeijing 100080

Magnetic properties and crystallization of amorphous Fe_(62)Co_(15.5)Nd_(4)B_(18.5) alloy are *** Curie temperature of the present sample is 127K higher than that of amorphous Fe_(77.5)Nd_(4)B_(18.5) alloy,but their crystallization temperature is compatible with each other.A coercive field of 2.34kOe,a remanence of 12.3kG and an energy product of 11.6MGOe are obtained at room temperature in the Fe_(62)Co_(15.5)Nd_(4)B_(18.5) alloy annealed at 650°*** 15.5at.%-Co substitution for Fe results in an increase of about 1l0K in Tc of 2:14:1 phase.

关键词： alloy crystallization amorphous

Hysteresis model of magnetostrictive actuators and its numerical realization

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2007年第7期8卷 1059-1064页

作者： TANG Zhi-feng LV Fu-zai XIANG zhan-qin Modern Manufacture Engineering Institute Zhejiang University Hangzhou 310027 China

This paper presents two numerical realization of Preisach model by Density Function Method (DFM) and F Function Method (FFM) for a giant magnetostrictive actuator (GMA). Experiment and simulation showed that FFM is better than DFM for predicting precision of hysteresis loops. Lagrange bilinear interpolation algorithm is used in Preisach numerical realization to enhance prediction performance. A set of hysteresis loops and higher order reversal curves are predicted and experimentally verified. The good agreement between the measured and predicted curves shows that the classical Preisach model is effective for modelling the quasi-static hysteresis of the GMA.

关键词： Magnetostrictive Actuator Hysteresis Density Function Method (DFM) F Function Method (FFM)

Study on the Total Synthesis of Ecteinascidin 743 and Its Analogues--Construction of A Pentacyclic Intermediate

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Chinese Chemical Letters 2003年第1期14卷 1-2页

作者： Ye feng TANG zhan Zhu LIU 等 InstituteofMatcriaMcdica ChineseAcademyofMedicalSciences&PekingUnionMedicalCollegeBeijing100050 InstituteofMatcriaMcdica ChineseAcademyofMedicalSciences&PekingUnionMedicalC

A concise and efficient synthesis of the pentacyclic intermediate 1, as a simple model compound of Ecteinascidin 743 and its analogues, is described.

关键词： Pentacyclic intermediate ecteinascidin 743 L-dopa.

Oxide coating mechanism during fluidized bed reduction: solid-state reaction characteristics between iron ore particles and MgO

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International Journal of Minerals,Metallurgy and Materials 2016年第9期23卷 1019-1028页

作者： Lei guo Jin-tao Gao Yi-wei Zhong Han Gao zhan-cheng guo State Key Laboratory of Advanced Metallurgy University of Science and Technology Beijing

Experiments on the solid-state reaction between iron ore particles and MgO were performed to investigate the coating mechanism of MgO on the iron ore particles＇ surface during fluidized bed reduction. MgO powders and iron ore particles were mixed and compressed into briquettes and, subsequently, roasted at different temperatures and for different time periods. A Mg-containing layer was observed on the outer edge of the iron ore particles when the roasting temperature was greater than 1173 K. The concentration of Fe in the Mg-containing layer was evenly distributed and was approximately 10wt%, regardless of the temperature change. Boundary layers of Mg and Fe were observed outside of the iron ore particles. The change in concentration of Fe in the boundary layers was simulated using a gas–solid diffusion model, and the diffusion coefficients of Fe and Mg in these layers at different temperatures were calculated. The diffusion activation energies of Fe and Mg in the boundary layers in these experiments were evaluated to be approximately 176 and 172 k J/mol, respectively.

关键词： fluidized beds coating solid reaction ferric oxide magnesia diffusion coefficient