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N-Oxide heterocycles and imidazoles replacing ring D of calanolides against Mycobacterium tuberculosis

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Chinese Chemical Letters 2016年第1期27卷 51-54页

作者： zi-jie Liu Xiao-Yong Guo Gang Liu Institute of Materia Medica Chinese Academy of Medical Sciences and Peking Union Medical College Tsinghua-Peking Center for Life Sciences and Department of Pharmacology and Pharmaceutical Sciences School of Medicine Tsinghua University

We have explored the chemistry of N-oxide heterocycles and imidazoles replacing ring D of the natural product（＋）-calanolide A, and have synthesized 12 new analogues, two of which were active against both R Mtb and ... 详细信息

关键词： Mycobacterium tuberculosis (+)-Calanolide A N-Oxide heterocycle Benzoimidazole Bioreductive drug

Magnetic Properties of Spin-1/2 Ising Superlattice

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Communications in Theoretical Physics 2007年第5期47卷 955-960页

作者： LIU Wei-jie XIN zi-Hua HU Hong-Liang College of Science Shanghai University Shanghai 200444 China

Using the effective-field theory we studied the magnetic properties of a spin-1/2 Ising supedattice, which consist of three different ferromagnet materials. The magnetic behavior of this superlattice is examined. The critical temperature and the compensation temprature of the system are studied as a function of the exchange interactions between the nearest-neiboring spins across the interface and in the intraface. Temperature dependence of magenetizations is also given.

关键词： Ising superlattice effective field theory phase transition compensation point

Metal-Catalyzed Substrate-Directed Enantioselective Functionalization of Unactivated Alkenes

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Chinese Journal of Chemistry 2019年第11期37卷 1174-1180页

作者： zi-Xuan Wang Xiao-Yan Bai Bi-jie Li Center of Basic Molecular Science(CBMS) Department of ChemistryTsinghua UniversityBeijing 100084China

Alkenes are versatile compounds that are available on large scales in industry or through chemical *** functionalization of unactivated alkenes in a chemo-,regio-,diastereo-and enantioselective fashion is a highly sought-after goal in organic ***-directed enantioselective functionalization of unactivated alkenes provides an important strategy to achieve this *** a functional group on the alkene substrate as a native coordinating group,a two-point binding mode of the substrate to the metal center enables effective control of regio-;diastereo-and *** this strategy,a variety of enantioselective functionalization methods have been developed *** recent advances in this area are highlighted here.

关键词： synthesis. enantioselective versatile

Molecular identification, expression and function analysis of peroxidasin in Chilo suppressalis

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Insect Science 2020年第6期27卷 1173-1185页

作者： Chun-Ping Ma zi-mu Guo Feng-Li Zhang Jian-Ya Su Key Laboratory of Integrated Management of Crop Diseases and Pests(Ministry of Education) College of Plant ProtectionNanjing Agricultural UniversityNanjingChina

Peroxidasin plays a unique role in the formation and stability of extracellular matrix(ECM)in the animal kingdom;however,it was only characterized in Diptera,not in other insect *** this study peroxidasin(CsPxc/)was first identified and characterized from Chilo suppressalis,a lepidopteran *** complementary DNA with a 4080 bp open reading frame encodes a peptide of 1359 amino acids;the derived amino acid sequence of CsPxd harbors the typical structural characteristics of peroxidasin family in heme-peroxidase superfamily,including the signal peptide at N-terminal,leucine-rich repeat domain,Ig-loop motifs and peroxidase domain,signifying the extracellular location of protein and the involvement in ECM *** expression reveals CsPxd protein displays peroxidase activity on H2O2,justifying the membership of *** analysis shows the monophyletic evolution pattern of peroxidasin in insect phyle,and moreover only one peroxidasin is present in each species of insects,suggesting its evolutionary conservation on *** messenger RNA is mainly expressed in egg and the final instar larvae *** of peroxidasin double-stranded RNA into the final instar larvae impacts the cuticle sclerotization during the metamorphosis from larvae to pupa,and eventually lead to lethality of larvae and *** results suggest the presence of collagen crosslink in chorion and cuticle of insects,and indicate peroxidasin plays a role in the development of chorion and cuticle;furthermore peroxidasin might be the one of potential target genes for pest control using RNA interference.

关键词： Chilo suppressalis cuticle sclerotization peroxidase peroxidasin RNA interference

Rate Constants for Reaction Between Hydroxyl Radical and Dimethyl Sulfide Under Real Atmospheric Condition

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Chinese Journal of Chemical Physics 2008年第5期21卷 407-414页

作者： Hai-tao Wang Chang-jiang Hu Yu-jing mu Yu-jie Zhang Research Center for Eco-Environmental Sciences Chinese Academy of Sciences Beifing 100085 China

The rate constants of the reaction between hydroxyl radical （OH-） and dimethyl sulfide （DMS） were investigated by using the relative methods in air, N2, and 02. Strong influences of ground state oxygen O（3p） on DMS consumption were found by the photolysis of HONO and CH3ONO as OH. sources, and the rate constants obtained in these systems varied significantly. The rate constants of the reaction between DMS and OH- （generated by photolysis of H2 O2） at room temperature were 8.56 × 10^-12, 11.31× 10^-12, and 4.50× 10^-12 cm3/（molecule.s）, in air, O2, and N2, respectively. The temperature dependence of the rate constants for OH- with DMS over the temperature range of 287-338 K was also investigated in nitrogen and air, and the Arrhenius expression was obtained as follows： kaire=（7.24±0.28）× 10^-13exp[（770.7±E97.2）/T], kN2 =（3.40±0.15） × 10^-11 exp[-- （590.3±165.9）/T].

关键词： Dimethyl sulfide Hydroxyl radical Ground state oxygen Kinetics

Geometric heat pump:Controlling thermal transport with time-dependent modulations

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Frontiers of physics 2022年第1期17卷 155-168页

作者： zi Wang Luqin Wang Jiangzhi Chen Chen Wang jie Ren Center for Phononics and Thermal Energy Science China-EU Joint Lab on NanophononicsShanghai Key Laboratory of Special Artificial Microstructure Materials and TechnologySchool of Physics Science and EngineeringTongji UniversityShanghai200092China Department of Physics Zhejiang Normal UniversityJinhua321004China

The second law of thermodynamics dictates that heat simultaneously flows from the hot to cold bath on average. To go beyond this picture, a range of works in the past decade show that, other than the average dynamical heat flux determined by instantaneous thermal bias, a non-trivial flux contribution of intrinsic geometric origin is generally present in temporally driven systems. This additional heat flux provides a free lunch for the pumped heat and could even drive heat against the bias. We review here the emergence and development of this so called “geometric heat pump”, originating from the topological geometric phase effect, and cover various quantum and classical transport systems with different internal dynamics. The generalization from the adiabatic to the non-adiabatic regime and the application of control theory are also discussed. Then, we briefly discuss the symmetry restriction on the heat pump effect, such as duality, supersymmetry and time-reversal symmetry. Finally, we examine open problems concerning the geometric heat pump process and elucidate their prospective significance in devising thermal machines with high performance.

关键词： geometric phase heat pump stochastic heat transport non-adiabatic control

Evaluating the Impact of Optical Axis Stability on Exoplanet Detection

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Research in Astronomy and Astrophysics 2022年第2期22卷 86-91页

作者： Dong-jie Tan Jia-Cheng Liu zi Zhu Niu Liu School of Astronomy and Space Science Key Laboratory of Modern Astronomy and Astrophysics(Ministry of Education)Nanjing University163 Xianlin Avenue210023 NanjingChina

For detecting exoplanets with high precision,using the angular distance between the two stars to detect the periodic motion of the star will be a better *** approach can avoid importing the position error of the reference catalog in the process that uses a traditional photographic plate to derive the star position *** the precision level of microarcseconds,the error caused by optical axis deviation is not *** this paper,we evaluate the impact of the stability of the optical axis on the relative angular distance measurement from the aspects of theoretical analysis and numerical *** the angular distance error limit of 1 microarcsecond is given,the upper limit of optical axis deviation is estimated to be 68 *** addition,when limiting the deviation of the optical axis,we give the corresponding error allowance of angular distance ***,we also discuss the way to resolve the problem of CCD distortion and focal length change on the measurement of angular *** work in this paper is of guiding significance to the design of a telescope.

关键词： instrumentation:high angular resolution methods:numerical planets and satellites:detection

Organic Semiconducting Materials Based on BDOPV:Structures,Properties,and Applications

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Chinese Journal of Chemistry 2020年第1期38卷 13-24页

作者： Li Ding zi-Yuan Wang jie-Yu Wang Jian Pei College of Chemistry and Molecular Engineering Peking UniversityBeijing 100871China

What are the major current research activities of your group?To develop high performance organic semiconducting and conducting materials and also to understand their structure-property *** are also interested in the effect of the aggregation states of the con-jugated polymers on their electronic properties,the doping process and *** is the most important personality for scientific research?Curiosity and the desire to ***,one should enjoy and be happy in the process of scientific exploration.

关键词： mechanism. conducting aggregation

Realizing high initial Coulombic efficiency in manganese-based layered oxide cathodes for sodium-ion batteries via P2/O'3 biphasic structure optimization

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Rare Metals 2024年第5期43卷 2093-2102页

作者： Bo Peng zi-Hao Zhou Ping Xuan jie Xu Lian-Bo Ma School of Materials Science and Engineering Anhui University ofTechnologyMa'anshan 243002China Anhui Product Quality Supervision&Inspection Research Institute Hefei 230051China

Mn-based layered oxides are among the most promising cathode materials for sodium-ion batteries owing to the advantages of abundance,environmenta friendliness,low cost and high specific capacity.P2 and O'3 are two representative structures of Mn-based layered ***,the P2 structure containing insufficien Na generally exhibits low initial charge capacity,while O'3structure with sufficient Na delivers high initial charge capacity but poor cycle *** study prepared a multitude of Na_(x)MnO_(2)(x=0.7,0.8,0.9)cathode materials with varying P2/O'3 ratios and further investigated their electrochemical *** optimized Na_(0.8)MnO_(2) comprising 69.9 wt%O'3 and 30.1 wt%P2 phase,exhibited relatively balanced specific capacity,Coulombic efficiency and cycle ***,it achieved a high specific capacity of 128.9 mAh·g^(-1) with an initia Coulombic efficiency of 98.2%in half-cell configuration The Na_(0.8)MnO_(2)//hard carbon full cell also achieved a high specific capacity of 126.7 mAh·g^(-1) with an initia Coulombic efficiency of 98.9%.Moreover,the capacity fading mechanism was revealed by combining in-situ and ex-situ X-ray *** findings of this study provide theoretical guidance for further modification design of Mnbased layered cathodes.

关键词： Sodium-ion batteries Cathode materials Mn-based layered oxides P2/0'3 composites