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Production representation of partial wave scattering amplitudes and the fo（600） particle

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Frontiers of physics 2013年第5期8卷 540-547页

作者： Han-qing zheng Department of Physics and State Key Laboratory of Nuclear Physics and Technology Peking University Beijing 100871 China

The establishlnent of production representation of partial wave scattering alnplitudes is reviewed in the context of quantum field theory. Its relation to the production representation, or Ning Hu representation in quantum mechanical scattering theory is pointed out. One of the most important application of the production representation is the physics of the fo（600） and K（700） scalar hadron resonances, on which we also give a brief review. It is emphasized that all evidences accunmlated so far are consistent with the picture that the fo（600） meson is the chiral partner of the Nambu Goldstone bosons in a linear realization of chiral symmetry.

关键词： scalar mesons chiral symmetry unitarization

Studies on the Quantitative Structure-activity Relationship of Toxicity of Chlorophenol Serial Compounds in the ab initio Methods and Substitutive Position of Chlorine Atom (N_(PCS))

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Chinese Journal of Structural Chemistry 2007年第8期26卷 933-938页

作者： zheng qing WANG Lian-Sheng Chemistry ＆ Bioengineering College Yancheng Institute of Technology Yancheng Jiangsu 224003 China School of the Environment Nanjing University Nanjing Jiangsu 210093 China

20 Quantum chemical parameters of chlorophenol compounds were fully optimized by using B3LYP method on both 6-31G^＊ and 6-311G^＊ basis sets. These structural parameters are taken as theoretical descriptors, and the experimental data of 20 compounds＇ aquatic photogen toxicity（-lgEC50） are used to perform stepwise regression in order to obtain two predicted -lgEC50 correlation models whose correlation coefficients R^2 are respectively 0.9186 and 0.9567. In addition, parameters of chlorine atom＇s substitutive positions and their correlations （NPCs） are taken as descriptors to obtain another predicted -lgEC50 model with the correlation coefficient R2 of 0.9444. Correlation degree of each independent variable in the three models is verified by using variance inflation factors （VIF） and t value. In the cross-validation method, cross-validation coefficients q^2 of 3 models are respectively 0.8748, 0.9119 and 0.8993, which indicates that the relativity and prediction ability of this model are superior to those of the model obtained by topological and BLYP methods.

关键词： chlorophenol toxicity (-lgEC50) linear dissolving energy theory density functional theory (DFT) substitutive position of chlorine atom (NPCS) QSAR

Prediction of the local and total thermal insulations of a bedding system based on the 3D virtual simulation technology

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Building Simulation 2023年第8期16卷 1467-1480页

作者： qing zheng Hongbo Wang Ying Ke School of Textile Science and Engineering Jiangnan UniversityWuxi 214122China School of Design Jiangnan UniversityWuxi 214122China

The thermal insulation of a bedding system is one of the most critical factors affecting sleeping thermal *** study reported a mathematical model to evaluate both local and total thermal insulations of a bedding *** determine the geometric parameters in the model,the geometric model of the bedding system was developed using a 3D virtual simulation *** reliability was validated by comparing it with the 3D scanning *** predicted local and total thermal insulations of bedding systems were compared with those measured by the thermal manikin obtained in a previous *** bedding systems included six down quilts with different filling weights and involved three body *** results showed that the predicted thermal insulation values agreed well with the experimental *** predicted local and total thermal insulations were with acceptable accuracy,whose errors were within 20%and 10%,***,the research discussed the effects of two main parameters(i.e.,the proportions and partial thermal resistances of heat transfer parts)on bedding thermal insulations and provided practical suggestions for regulating bedding thermal *** study has important implications for evaluating the thermal comfort of the bedding system and contributes to improving the sleeping environment.

关键词： thermal insulation prediction model bedding system heat transfer virtual simulation

Nuclear magnetic resonance measurement station in SECUF using hybrid superconducting magnets

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Chinese Physics B 2018年第7期27卷 107-111页

作者： zheng Li Guo-qing zheng Beijing National Laboratory for Condensed Matter Physics Institute of PhysicsChinese Academy of SciencesBeijing 100190China School of Physical Sciences University of Chinese Academy of SciencesBeijing 100190China

Nuclear magnetic resonance （NMR） is one of the most powerful tools to explore new quantum states of condensed matter induced by high magnetic fields at a microscopic level. High magnetic field enhances the intensity of the NMR signal, and more importantly, can induce novel phenomena. In this article, examples are given on the field-induced charge density wave （CDW） in high-To superconductors and on the studies of quantum spin liquids. We provide a brief introduction to the high magnetic field NMR platform, the station 4 of the Synergetic Extreme Condition User Facility （SECUF）, being built at Huairou, Beijing.

关键词： nuclear magnetic resonance (NMR) high magnetic field charge density wave (CDW)

Active disturbance rejection control： some recent experimental and industrial case studies

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Control Theory and Technology 2018年第4期16卷 301-313页

作者： qing zheng Zhiqiang GAO Department of Aerospace Industrial and Mechanical Engineering California Baptist University Riverside CA 92504 U.S.A. Department of Electrical and Computer Engineering Cleveland State University Cleveland OH 44115 U.S.A.

This paper presents a summary of some recent experimental and industrial case studies of active disturbance rejection control （ADRC）. ADRC is a novel disturbance estimation and rejection concept, leading to a new technology with a distinct advantage where, unlike most existing methods, disturbances, internal and external, are actively estimated and rejected. Applications of the new approach in solving industry-wide bench mark problems have led to a slew of innovative solutions. The scope of the applications shown in this paper includes motion control, robotic-enhanced limb rehabilitation trainings, fuel cell systems, and the two-mass-spring benchmark problem. Recent production line validation results obtained are also included.

关键词： Active disturbance rejection control applications production line validation

Active disturbance rejection control： between the formulation in time and the understanding in frequency

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Control Theory and Technology 2016年第3期14卷 250-259页

作者： qing zheng Zhiqiang GAO Department of Electrical and Computer Engineering Gannon University Erie PA 16541 U.S.A. Center for Advanced Control Technologies Department of Electrical and Computer Engineering Cleveland State University Cleveland OH 44115 U.S.A.

With the rapid deployments of the active disturbance rejection control （ADRC） as a bonafide industrial technology in the background, this paper summarizes some recent results in the analysis of linear ADRC and offers explanations in the frequency response language with which practicing engineers are familiar. Critical to this endeavor is the concept of bandwidth, which has been used in a more general sense. It is this concept that can serve as the link between the otherwise opaque state space formulation of the ADRC and the command design considerations and concerns shared by practicing engineers. The remarkable characteristics of a simple linear ADRC was first shown in the frequency domain, followed by the corresponding analysis in time domain, where the relationship between the tracking error and the ADRC bandwidth is established. It is shown that such insight is only possible by using the method of solving linear differential equations, instead of the more traditional techniques such as the Lyapunov methods, which tend to be more conservative and difficult to grasp by engineers. The insight obtained from such analysis is further demonstrated in the simulation validation.

关键词： Active disturbance rejection control extended state observer uncertain systems stability bandwidth

Studies on the Quantitative Structure-activity Relationship of Substituted Biphenyls by Density Function Theory (DFT)

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Chinese Journal of Structural Chemistry 2007年第2期26卷 229-233页

作者： HAN Xiang-Yun zheng qing Department of Chemical Engineering YanchengInstitute of Technology Jiangsu 224003 China

Geometrical configurations of 16 substituted biphenyls were computed at the B3LYP/6-311G^＊＊ level with Gaussian 98 program. Based on linear solvation energy theory, lgKow as well as the structural and thermodynamic parameters obtained at this level was taken as theoretical descriptors, and corresponding equation predicting the toxicity of Daphnia magna （-lgEC5o） was thus obtained, in which three parameters were contained, i.e., n-octanol/water partition coefficients （lgKow）, dipole moment of the molecules（ μ） and entropy （S°）. For this equation, R^2 = 0.9582, q^2 = 0.8921 and SD = 0.102. The absolute t-scores of three variables are larger than the standard one in the confidence range of 95%, which confirms the creditability and stability of this model.

关键词： substituted biphenyl linear solvation energy theory,DFT method Daphnia magna toxicity

Dracaenoside A and B, New C-22 Steroidal Lactone Glycosides from the Stem of Dracaena cochinchinensis

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Chinese Chemical Letters 2003年第12期14卷 1261-1264页

作者： qing an zheng Chong RenYANG State Key Laboratory of Phytochemistry and Plant Resources in West China Kunming Institute of BotanyChinese Academy of SciencesKunming 650204

Two new C-22 steroidal lactone glycosides, named dracaenoside A and B were isolated from the methanol extract of the fresh stem of Dracaena cochinchinensis. Their structures were established as (20S)3b,14a,16b-trihydroxy pregn-5-ene-22-carboxylic acid (22,16)-lactone 3-O-a- L-rhamnopyranosyl (1→2)[ a-L-rhamnopyranosyl (1→4)]-b-D-glucopyranoside and (20S)3b, 14a, 16b-trihydroxy pregn-5-ene-22-carboxylic acid (22,16)-lactone 3-O-a-L-rhamnopyranosyl (1→2) [b-D-glucopyranosyl(1→3)]-b-D-glucopyranoside by means of 2D NMR spectral and chemical methods. It is the first time that steroidal lactone glycosides were isolated from the genus Dracaena.

关键词： Dracaena cochinchinensis Agavaceae C-22 steroidal glycosides dracaenoside A dracaenoside B.

Bowel preparation before colonoscopy: Consequences, mechanisms, and treatment of intestinal dysbiosis

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World Journal of Gastroenterology 2025年第2期31卷 13-26页

作者： Ze-Long zheng qing-Fan zheng Li-Qiang Wang Yi Liu Department of Gastroenterology(Endoscopy Center) China-Japan Union Hospital of Jilin UniversityChangchun 130033Jilin ProvinceChina

The term“gut microbiota”primarily refers to the ecological community of various microorganisms in the gut,which constitutes the largest microbial community in the human *** adequate bowel preparation can improve the results of colonoscopy,it may interfere with the gut *** preparation for colonoscopy can lead to transient changes in the gut microbiota,potentially affecting an individual’s health,especially in vulnerable populations,such as patients with inflammatory bowel ***,measures such as oral pro-biotics may ameliorate these adverse *** focused on the bowel prepa-ration-induced changes in the gut microbiota and host health status,hypothesized the factors influencing these changes,and attempted to identify measures that may reduce dysbiosis,thereby providing more information for individualized bowel preparation for colonoscopy in the future.

关键词： Bowel preparation Colonoscopy Microbiota Inflammatory bowel disease Probiotics