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Investigation on the eigenvalue-equation problem of molecular crystals and polymers

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Chinese Journal of Chemistry 1990年第6期8卷 481-491页

作者： yan, ji-min ZHANG, Qi-Yuan, Institute of Chemistry, Academia Sinica, Beijing 100080 Institute of Chemistry Academia Sinica Beijing 100080

One-dimensional periodic system, such as molecular crystal and polymer, can be expressed as ... ABABAB ... structure, where A and B stand for a complete molecule or a part of a molecule. When (AB) is taken as a structure unit, one can obtain the complex generalized eigenvalue-equation H^(AB) (k) C^(AB) (k)=S^(AB) (k)C^(AB) (k)E^(AB) (k); and if (BA)is taken as a structure unit, the corresponding eigenvalue-equation is H^(BA)(k) C^(BA)(k)=S^(BA)(k) C^(BA)(k) E^(BA)(k). The relationship between the two equations has been investigated. The results of theoretical analysis are E_m^(BA) (k)= E_m^(AB)(k); C_(j_am)^(BA)(k)=C_(j_am)^(AB). exp (i△) and C_(j_bm)^(BA)(k)=C_(j_bm)^(AB)(k). exp[i(k.R_(-1)+△)]=C_(j_bm)^(AB)(k)× exp (i△??) where j_a and j_b are the index number of atomic orbitals within (A) and (B) respectively, and m stands for the index number of crystal or polymer orbitals. This result has been verified by the concrete calculation of three periodic systems: (1) hydrogen-molecular chain, ...H (A) H (B) ... H (A) H (B) ..., (2) polyphenylene, ... (A) (B) (A) (B) ..., where (A) and (B) stand for =C (CH=): and (=HC)_2 C= respectively, and (3) the TCNQ molecular column, ... TCNQ (A). TCNQ (B) ... TCNQ (A). TCNQ(B)... . The results can be generalized to two- and three-dimensional systems straightforwardly.

关键词： BA exp AB

Investigation on the potential barrier to internal rotation in molecules——Ab initio calculation and energy partition of the internal rotation barrier in complex molecule H_3N-BH_3

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Chinese Journal of Chemistry 1992年第5期10卷 385-389页

作者： ZHANG, Qi-Yuan yan, ji-min Institute of Chemistry, Chinese Academy of Sciences, Beijing 100080 Institute of Chemistry Chinese Academy of Sciences Beijing 100080

Based on the ab initio/6-31Gcalculation, the potential barrier to internal rotation in mol-ecule HN--BHhas been studed by means of PD/LSF atomic charge model and Buckingham（exp--6-1）energy partition method. The results indicate that the order of the contributions of the componentsto the total energy barrier △E is |△V|（electrostatic） >|△V| （charge transfer）>|△V| （exchangerepulsion）>|△V| （dispersion）. For △Vthere are maxima at θ= 30°and 90°, and a saddle atθ= 60°. There are good linear relationships for the total barrier △E, △Vand △Vwith cos3θrespectively, and the same for the dipole moment from PD/LSF model (μ) and that from abinitio calculation (μ) vs. cos3θ respectively.

关键词： Ab initio calculation and energy partition of the internal rotation barrier in complex molecule H3N-BH3

Compound Product of Hypermatrices

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Journal of Systems Science & Complexity 2024年第1期37卷 169-183页

作者： CHENG Daizhan MENG min ZHANG Xiao ji Zhengping Key Laboratory of Systems and Control Academy of Mathematics and Systems ScienceChinese Academy of SciencesBeijing 100190China Department of Control Science and Engineering School of Electronics and Information EngineeringTongji UniversityShanghai 201210China National Center for Mathematics and Interdisciplinary Sciences Chinese Academy of SciencesBeijing 100190China School of Mathematical Sciences University of Chinese Academy of SciencesBeijing 100149China.

The semi-tensor product(STP)of matrices is generalized to multidimensional arrays,called the compound product of *** product is first defined for three-dimensional hypermatrices with compatible orders and then extended to general *** different types of hyperdeterminants are introduced and certain properties are *** Lie groups and Lie algebras corresponding to the hypermatrix products are ***,these results are applied to dynamical systems.

关键词： Compound semi-tensor product hyperdeterminants hypereigenvalues and hypereigenvectors hypergeneral linear groups hypermatrices.

Sustainable and practical semi-heterogeneous photosynthesis of 5-amino-1,2,4-thiadiazoles over WS_(2)/TEMPO

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Chinese Chemical Letters 2024年第8期35卷 250-253页

作者： jia-Cheng Hou Hong-Tao ji Yu-Han Lu jia-Sheng Wang Yao-Dan Xu yan-yan Zeng Wei-min He School of Chemistry and Chemical Engineering University of South ChinaHengyang 421001China

An eco-friendly and practical method for the clean preparation of 5-amino-1,2,4-thiadiazoles was *** WS_(2)as the semiconductor photocatalyst,both TEMPO and O_(2)(in air)as the redox catalysts,a variety of thiadiazoles were semi-heterogeneously formed in high to quantitative yields and could be easily collected by CPME extraction and ***,the catalytic system can be reusable for at least 5 reaction runs.

关键词： Green chemistry Thiadiazoles Heterogeneous catalyst Redox catalyst Extraction

Quantum-chemical investigation on hydrogen bonding interaction of hydrogen fluoride dimer at various mutual orientations

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Chinese Journal of Chemistry 1990年第1期8卷 11-20页

作者： yan ji-min (J. M. yan) Institute of Chemistry,Academia Sinica,Beijing 100080WILLIAMS,D.E.Department of Chemistry,University of Louisville Louisville,KY,USA Institute of Chemistry Academia Sinica Beijing 100080 Department of Chemistry University of Louisville Louisville KY USA

Hydrogen bonding interaction in hydrogen fluoride dimer has been investigated by quan- tum-chemical calculation with 6-311G^(**) basis set at various mutual *** charges and charge transfer have been calculated by means of potential-derived method,and decomposition of hydro- gen bonding interaction has been *** calculation results show that there is a variation range for the energy-stable orientations,the charge transfer in the range presents maximum value,and the charge transfer interaction plays a decisive role in the hydrogen bonding.

关键词： net Quantum-chemical investigation on hydrogen bonding interaction of hydrogen fluoride dimer at various mutual orientations

Monothetic and conductive network and mechanical stress releasing layer on micron-silicon anode enabling high-energy solid-state battery

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Rare Metals 2024年第3期43卷 1017-1029页

作者： Xiang Han min Xu Lan-Hui Gu Chao-Fei Lan min-Feng Chen Jun-jie Lu Bi-Fu Sheng Peng Wang Song-yan Chen ji-Zhang Chen College of Materials Science and Engineering Co-Innovation Center of Efficient Processing and Utilization of Forestry ResourcesNanjing Forestry UniversityNanjing210037China Department of Physics Xiamen UniversityXiamen361005China Western Digital Corporation MilpitasCA95035USA

Silicon has ultrahigh capacity,dendrite-free alloy lithiation mechanism and low cost and has been regarded as a promising anode candidate for solid-state *** to the low infiltration of solid-state electrolyte(SSE),not the unstable solid-electrolyte interphase(SEI),but the huge stress during lithiation-and delithiation-induced particle fracture and conductivity lost tend to be the main *** this study,starting with micron-Si,a novel monothetic carbon conductive framework and a MgO coating layer are designed,which serve as electron pathway across the whole electrode and stress releasing layer,*** addition,the in situ reaction between Si and SSE helps to form a LiF-rich and mechanically stable SEI *** a result,the mechanical stability and charge transfer kinetics of the uniquely designed Si anode are significantly ***,high initial Coulombic efficiency,high capacity and durable cycling stability can be achieved by applying the Si@MgO@C anode in *** example,high specific capacity of 3224.6 mAh·g^(-1)and long cycling durability of 200 cycles are *** work provides a new concept for designing alloy-type anode that combines surface coating on particle and electrode structure design.

关键词： Lithium-ion battery(LIB) Solid-state electrolyte(SSE) Silicon anode Stress relief Coating

Efficacy and safety of Yiqi Peiyuan granules for improving the short-term prognosis of patients with acute kidney injury:A multicenter,double-blind,placebo-controlled,randomized trial

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Journal of Integrative Medicine 2024年第3期22卷 279-285页

作者： jia-jia Wu Tian-yi Zhang Ying-hui Qi min-yan Zhu yan Fang Chao-jun Qi Li-ou Cao ji-fang Lu Bo-han Lu Lu-min Tang jian-xiao Shen Shan Mou Department of Nephrology Molecular Cell Lab for Kidney DiseaseShanghai Peritoneal Dialysis Research CenterUremia Diagnosis and Treatment CenterRenji Hospital Affiliated to Shanghai Jiaotong University School of MedicineShanghai 200127China Department of Nephrology Shanghai Pudong New Area Punan HospitalShanghai 200125China Department of Nephrology Ningbo Hangzhou Bay HospitalNingbo 315336Zhejiang ProvinceChina

Background:Yiqi Peiyuan(YQPY)prescription,a composite prescription of traditional Chinese medicine,has been used to prevent or delay the continued deterioration of renal function after acute kidney injury(AKI)in some institutions and has shown considerable ***:This is the first randomized controlled trial to assess efficacy and safety of YQPY for improving short-term prognosis in adult patients with ***,setting,participants and interventions:This is a prospective,double-blind,multicenter,randomized,and placebo-controlled clinical trial.A total of 144 enrolled participants were randomly allocated to two groups according to a randomization ***,caregivers and investigators assessing the outcomes were blinded to group *** in the YQPY group received 36 g YQPY granules twice a day for 28 *** in the placebo group received a placebo in the same dose as the YQPY *** outcome measures:The primary outcome was the change in the estimated glomerular filtration rate(eGFR)between baseline and after 4 and 24 weeks of *** secondary outcomes were the change of serum creatinine(Scr)level between baseline and after treatment,and the incidence of endpoint events,defined as eGFR increasing by more than 25%above baseline,eGFR>75 mL/min per1.73 m2or the composite endpoint,which was defined as the sum of patients meeting either of the above ***:Data from a total of 114 patients(59 in the YQPY group and 55 in the control group)were *** mean changes in eGFR and Scr in weeks 4 and 24 had no difference between the two *** further subgroup analysis(22 in the YQPY group and 31 in the control group),the mean change in eGFR after treatment for 4 weeks was 27.39 mL/min per 1.73 m2in the YQPY group and 5.78 mL/min per1.73 m2in the placebo group,and the mean difference between groups was 21.61 mL/min per 1.73 m2(P<0.001).Thirteen(59.1%)patients in the YQPY group and 5(16.1%)in the placebo g

关键词： Chinese herbal medicine Randomized controlled trial Acute kidney injury Renal function

Basic Survey Scheduling for the Wide Field Survey Telescope(WFST)

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Research in Astronomy and Astrophysics 2024年第1期24卷 59-69页

作者： yan-Peng Chen ji-An jiang Wen-Tao Luo Xian-Zhong Zheng min Fang Chao yang Yuan-Yu Hong Zong-Fei Lü Purple Mountain Observatory Chinese Academy of SciencesNanjing 210023China School of Astronomy and Space Science University of Science and Technology of ChinaHefei 230026China Department of Astronomy University of Science and Technology of ChinaHefei 230026China National Astronomical Observatory of Japan National Institutes of Natural Sciences2-21-1 OsawaMitakaTokyo 181-8588Japan Institute of Deep Space Sciences Deep Space Exploration LaboratoryHefei 230026China

Aiming at improving the survey efficiency of the Wide Field Survey Telescope, we have developed a basic scheduling strategy that takes into account the telescope characteristics, observing conditions, and weather conditions at the Lenghu site. The sky area is divided into rectangular regions, referred to as “tiles,” with a size of2°. 577 × 2°. 634 slightly smaller than the focal area of the mosaic CCDs. These tiles are continuously filled in annulars parallel to the equator. The brightness of the sky background, which varies with the moon phase and distance from the moon, plays a significant role in determining the accessible survey fields. Approximately 50connected tiles are grouped into one block for observation. To optimize the survey schedule, we perform simulations by taking into account the length of exposures, data readout, telescope slewing, and all relevant observing conditions. We utilize the Greedy Algorithm for scheduling optimization. Additionally, we propose a dedicated dithering pattern to cover the gaps between CCDs and the four corners of the mosaic CCD array, which are located outside of the 3° field of view. This dithering pattern helps to achieve relatively uniform exposure maps for the final survey outputs.

关键词： telescopes surveys Moon

Fuzzy-Model-Based Finite Frequency Fault Detection Filtering Design for Two-Dimensional Nonlinear Systems

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IEEE/CAA Journal of Automatica Sinica 2024年第10期11卷 2099-2110页

作者： Meng Wang Huaicheng yan jianbin Qiu Wenqiang ji Key Laboratory of Smart Manufacturing in Energy Chemical Process Ministry of EducationSchool of Information Science and EngineeringEast China University of Science and TechnologyShanghai 200237China Research Institute of Intelligent Control and Systems School of AstronauticsHarbin Institute of TechnologyHarbin 150080China School of Artificial Intelligence Hebei University of TechnologyTianjin 300401China IEEE

This article studies the fault detection filtering design problem for Roesser type two-dimensional(2-D)nonlinear systems described by uncertain 2-D Takagi-Sugeno(T-S)fuzzy ***,fuzzy Lyapunov functions are constructed and the 2-D Fourier transform is exploited,based on which a finite frequency fault detection filtering design method is proposed such that a residual signal is generated with robustness to external disturbances and sensitivity to *** has been shown that the utilization of available frequency spectrum information of faults and disturbances makes the proposed filtering design method more general and less conservative compared with a conventional nonfrequency based filtering design ***,with the proposed evaluation function and its threshold,a novel mixed finite frequency H_(∞)/H_(-)fault detection algorithm is developed,based on which the fault can be immediately detected once the evaluation function exceeds the ***,it is verified with simulation studies that the proposed method is effective and less conservative than conventional non-frequency and/or common Lyapunov function based filtering design methods.

关键词： Fault diagnosis finite frequency specifications mixed H_(∞)/H_(-)performance two-dimensional nonlinear systems