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Chinese Journal of Polymer Science 2002年第5期20卷 431-437页

作者： Zhong-ming Hu Ren-yuan Qian Shou-xi Chen Xiao-fang Chen Qi-feng zhou Centre for {2. Science, Institute of chemistry Chinese Academy of sciences, Beijing 100080, china Department of Polymer Science & Engineering college of chemistry & {2. Engineering Peking university Beijing 100871, china Chinese Acad Sci Inst Chem Ctr Mol Sci Beijing 100080 Peoples R China Peking Univ Coll Chem & Mol Engn Dept Polymer Sci & Engn Beijing 100871 Peoples R China

The kinetics of I-->N transition of a side chain nematic polymethacrylate has been studied by small angle depolarized light scattering intensity measurements using a charge coupled device linear image sensor. The polymer shows the transition temperatures K52.79I in degreesC, The H-v scattering intensity T(q,t) during the transition I (at 80.2.egreesC)-->N (at 75.8degreesC) shows that T(q) is independent of q for all t, and during the initial stage (in 6 s) T(t) increases exponentially with t. In the later stage of the transition T(t) approaches a saturation value in 2.min. This experimental result indicates that the I-->N transition of a liquid crystalline polymer is a spinodal type of phase transition mediated by orientation fluctuation.

关键词： side chain nematic polymer isotropic-nematic transition small angle depolarized light scattering

A DSC STUDY OF PHOTOPOLYMERIZATION OF POLYESTERS CONTAINING CONJUGATED DIACETYLENES

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Chinese Journal of Polymer Science 2000年第4期18卷 351-356页

作者： yao-wen Bai Xiao-fang Chen Dong Zhang Xin-hua Wan Qi-feng {2. Department of Polymer Science and Engineering, college of chemistry, Peking university, Beijing 100871, china Peking Univ Coll Chem Dept Polymer Sci & Engn Beijing 100871 Peoples R China

The photopolymerization of two kinds of prepolyesters containing conjugated diacetylene (PDA-6 and PDA-12. was investigated using DSC. By measuring the endothermic enthalpy of the prepolymers after different UV-irradiation times, the polymerizations were found to follow the first-order rate law which agreed with the results of other investigators using a different method. The endothermic enthalpy measurements of PDA-6 and PDA-12.before UV-irradiation precluded the possibility that the decrease of endothermic enthalpy was caused by thermal polymerization.

关键词： diacetylene-containing polyesters DSC enthalpy

SYNTHESIS AND PROPERTIES OF A NEW AZOBENZENE SIDE-CHAIN POLYMER CONTAINING A TEMPO RADICAL

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Chinese Journal of Polymer Science 2002年第4期20卷 285-290页

作者： Yong Zhang Ze-da Xu Xing-he Fan Xiao-fang Chen Xin-hua Wan Qi-feng zhou Department of Polymer Science and Engineering {2. of chemistry and molecular Engineering Peking university, Beijing 100871, china Peking Univ Coll Chem & Mol Engn Dept Polymer Sci & Engn Beijing 100871 Peoples R China

To allow anisotropies of optical properties in a magnetic field, nitroxide radical is introduced into the ortho-position of the phenylene ring in the side chain. A new azobenzene side-chain polymer (TEMPO-PAZ) containing TEMPO radical was synthesized. The polymer has a good solubility in organic solvents. The ESR spectrum of the polymer indicated three absorption lines characteristic of TEMPO radical. The optical phase conjugated responses (I-4) of the polymer films were investigated by degenerate four-wave mixing (DFWM). The experimental results showed that optical phase conjugated response of the TEMPO-PAZ could be easily controlled by choosing the appropriate direction of magnetic field presumably due to the nitroxide radical in the TEMPO-PAZ molecular structure. For the polymer investigated here, the nitroxide radical was introduced to increase optical phase conjugated response intensity in a magnetic field, aiming originally at searching for a new photo-active organic magnetic multifunctional materials.

关键词： azobenzene nitroxide radical polymer photo-active organic magnetic materials optical phase conjugated responses

Study of tree shrew biology and models: A booming and prosperous field for biomedical research

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Zoological Research 2024年第4期45卷 877-909页

作者： Yong-Gang yao Li Lu Rong-Jun Ni Rui Bi Ceshi Chen Jia-Qi Chen Eberhard Fuchs Marina Gorbatyuk Hao Lei Hongli Li Chunyu Liu Long-Bao Lv Kyoko Tsukiyama-Kohara Michinori Kohara Claudia Perez-Cruz Gregor Rainer Bao-Ci Shan fang Shen An-{2. Tang Jing Wang Wei Xia Xueshan Xia Ling Xu Dandan Yu Feng Zhang Ping Zheng Yong-Tang Zheng Jumin {2. Jiang-Ning {2. Key Laboratory of Genetic Evolution and Animal Models Yunnan Key Laboratory of Animal Models and Human Disease MechanismsKunming Institute of ZoologyChinese Academy of SciencesKunmingYunnan 650204China National Research Facility for Phenotypic&Genetic Analysis of Model Animals(Primate Facility) and National Resource Center for Non-Human PrimatesKunming Institute of ZoologyChinese Academy of SciencesKunmingYunnan 650107China KIZ-CUHK Joint Laboratory of Bioresources and molecular Research in Common Diseases Kunming Institute of ZoologyChinese Academy of SciencesKunmingYunnan 650204China Kunming college of Life Science University of Chinese Academy of SciencesKunmingYunnan 650204China Mental Health Center and Psychiatric Laboratory West China HospitalSichuan UniversityChengduSichuan 610041China Sichuan Clinical Medical Research Center for Mental Disorders ChengduSichuan 610044China German Primate Center Leibniz Institute of Primate ResearchGöttingen 37077Germany Department of Optometry and Vision Science School of OptometryUniversity of Alabama at BirminghamBirminghamAL 35294USA State Key Laboratory of Magnetic Resonance and Atomic and molecular Physics Innovation Academy for Precision Measurement Science and TechnologyChinese Academy of SciencesWuhanHubei 430071China wuhan National Laboratory for Optoelectronics Huazhong University of Science and TechnologyWuhanHubei 430074China Soong Ching Ling Institute of Maternity and Child Health International Peace Maternity and Child Health HospitalShanghai Jiao Tong University School of MedicineShanghai 200030China Transboundary Animal Diseases Center Joint Faculty of Veterinary MedicineKagoshima UniversityKagoshima-cityKagoshima 890-8580Japan Department of Microbiology and Cell Biology Tokyo Metropolitan Institute of Medical ScienceTokyo 156-8506Japan Pharmacology Department CinvestavMexico City 07360Mexico Department of Medicine University of FribourgFribourg CH-1700Switzerland Beijing Engineering Research Center of Radiog

The tree shrew(Tupaia belangeri)has long been proposed as a suitable alternative to non-human primates(NHPs)in biomedical and laboratory research due to its close evolutionary relationship with *** recent years,significant advances have facilitated tree shrew studies,including the determination of the tree shrew genome,genetic manipulation using spermatogonial stem cells,viral vector-mediated gene delivery,and mapping of the tree shrew brain ***,the limited availability of tree shrews globally remains a substantial challenge in the ***,determining the key questions best answered using tree shrews constitutes another *** shrew models have historically been used to study hepatitis B virus(HBV)and hepatitis C virus(HCV)infection,myopia,and psychosocial stress-induced depression,with more recent studies focusing on developing animal models for infectious and neurodegenerative *** these efforts,the impact of tree shrew models has not yet matched that of rodent or NHP models in biomedical *** review summarizes the prominent advancements in tree shrew research and reflects on the key biological questions addressed using this *** emphasize that intensive dedication and robust international collaboration are essential for achieving breakthroughs in tree shrew *** use of tree shrews as a unique resource is expected to gain considerable attention with the application of advanced techniques and the development of viable animal models,meeting the increasing demands of life science and biomedical research.

关键词： Tree shrew Animal model Neurodegenerative diseases Infectious diseases Neuroscience Phenome

A MOF built on 8-connected Y3 nodes demonstrates simultaneous reverse adsorptive separation: ethane over ethylene and propane over propylene

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Science china chemistry 2024年第11期67卷 3657-3661页

作者： Lu-Lu Ma Jiaqi Liu Kang zhou Zixuan Cao Jiafeng Miao Guo-Ping Yang yao-Yu Wang Jing Li Hao Wang Key Laboratory of Synthetic and Natural Functional Molecule chemistry of the Ministry of Education Shaanxi Key Laboratory of PhysicoInorganic Chemistry College of Chemistry & Materials Science Northwest University Hoffmann Institute of Advanced Materials Shenzhen Polytechnic University Shenzhen Senior High School Department of chemistry and Chemical Biology Rutgers University

Selective adsorption of paraffins over olefins（mostly C2.and C3） by porous solids could offer tremendous advantages for the purification of olefins, which is, however, challenging as it has stringent requirements on the pore dimensions and pore surface chemistry of the adsorbent. We report here a metal-organic framework（MOF） with novel topology, Y3（μ3-OH）(TCMPB)2.denoted as HIAM-316, TCMPB4-= 1,2.4,5-tetra（4-carboxy-3-methylphenyl）benzene), which shows reversed separation of C2.6/C2.4and C3H8/C3H6simultaneously. The ideal adsorbed solution theory（IAST） selectivities for equimolar binary mixtures of C2.6/C2.4and C3H8/C3H6were calculated to be 1.67 and 1.2. at 1 bar and 2.8 K for HIAM-316. Its capability of removing paraffines from paraffin/olefin mixtures is validated by breakthrough measurements. molecular simulations reveal that the preferential adsorption of paraffins over olefins by HIAM-316 may be attributed to the abundant carboxylate oxygen atoms along its channel.

关键词： metal-organic framework adsorption separation

Controlled free radical polymerization of styrene initiated from the alkoxyamine-functionalized silicon surface

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Science china chemistry 2005年第5期48卷 449-458页

作者： CHEN Zhijun1, zhou Sikai1, LU Wenzhong1, fang Shaoming1, JIANG Xiqun2.& YANG Changzheng2.1. {2. of Materials and Chemical Engineering, Zhengzhou university of Light Industry, Zhengzhou 450002. china 2. Laboratory of Mesoscopic Material Science and Department of Polymer Science & Engineering, {2. of chemistry & Chemical Engineering, Nanjing university, Nanjing 2.0093, china 1. college of Materials and Chemical Engineering Zhengzhou University of Light Industry 450002 Zhengzhou China 2. Laboratory of Mesoscopic Material Science and Department of Polymer Science & Engineering College of Chemistry & Chemical Engineering Nanjing University 210093 Nanjing China

We describe a new method of fabricating a brush-like polystyrene layer anchored on the surface of the silicon substrate, which involves three steps, namely (i) the attachment of 3-methacryloxypropyltrimethoxysilane onto the silicon surface; (ii) the reaction of vinyl moiety at another extremity of the anchored 3-methacryloxypropyltrimethoxysilane to 4-Hydroxyl-2. 2. 6, 6-tetramethyl-1-piperidinyloxy (HTEMPO?) catalyzed by azobisisobutyronitrile (AIBN); (iii) living free radical grafting polymerization of styrene in the presence of HTEMPO?. The controllable living free radical polymerization permits accurate control of both the molecular weight and the polydispersity. X-photoelectron spectroscopy measurement proved that the alkoxyamine initiator layer forms on the silicon surface. XPS and Ellipsometry measurements showed that the poly-styrene chains were covalently anchored onto the silicon surface. The thickness of the grafted polymer layer can be accurately manipulated by altering the polymerization time. The new method allows synthesizing random copolymer and block copolymers by the sequential growth of monomers from the substrate surface.

关键词： polymer brush, controlled living free radical polymerization, thickness, atomic force microscopy, 3-methacryloxypropyltrimethoxysilane.

Bisulfite-mediated base-free decarboxylative carbonylsulfination of alkenes:access to β-keto sultines

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Science china chemistry 2024年

作者： Yongxin Zhang Pan zhou Xinyue Ma Xiaoxiao Yang Xing fang Yuxi Wang Chao Shu State Key Laboratory of Green Pesticide Engineering Research Center of Photoenergy Utilization for Pollution Control and Carbon Reduction CCNU-uOttawa Joint Research Centre College of Chemistry Central China Normal University (CCNU) Key Laboratory of Functional molecular Solids Ministry of Education Anhui Normal University

A straightforward three-component decarboxylative cross-coupling of α-keto acids, alkenes and sodium bisulfite is established for the construction of otherwise challenging-to-access β-keto sultine derivatives. This reaction involves the photoinduced carbonylsulfination of alkenes and utilizes sodium bisulfite as both a sulfur dioxide surrogate and buffer agent for deprotonation of α-keto carboxylic acids. Of note, the practical procedure featured broad substrate scope and group tolerance for diverse biologically important molecules under mild and operationally simple conditions, using an organic photocatalyst. Mechanistic studies indicated that the transformation proceeds an apparent two-pronged radical addition/radical-polar crossover/SO2.nsertion/ionic cyclization relay process, distinct from traditional alkenes bifunctionalization.

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Aldh2.deficiency plays a dual role in lung tumorigenesis and tumor progression

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Genes & Diseases 2024年第3期11卷 144-147页

作者： Hongjia Zhang Xueqian Sun Zhanming Li Tingting Liu fang Zhang Xinyu Meng Kaimi Li Jianhua Xu Wei He Bo Jing Tong Wang Na Ni Beibei Sun Feng yao Yadi Wu Qi Wang Jing Du Eugene Y.Chin Binhua P.{2. Ping Jiang Lishun Wang Jiong Deng Key Laboratory of Cell Differentiation and Apoptosis of Chinese Minister of Education Department of PathophysiologyShanghai Jiao Tong University School of MedicineShanghai 200025China Shanghai Key Laboratory for Tumor Microenvironment and Inflammation Shanghai Jiao Tong University School of MedicineShanghai200025China Department of Pathology Kunming Medical UniversityKunmingYunnan 650500China Medical Research Center Binzhou Medical University HospitalBinzhouShandong 256600China Center for Traditional Chinese Medicine and Gut Microbiota Minhang HospitalFudan UniversityShanghai 201100China Department of Radiation Oncology Yantai Affiliated Hospital of Binzhou Medical UniversityYantaiShandong 264100China Department of Pathology Molecular Pathology Research CenterPeking Union Medical College HospitalChinese Academy of Medical Sciences and Peking Union Medical CollegeBeijing 100730China Department of Laboratory Medicine Shanghai Pulmonary Hospital Affiliated Tongji UniversityShanghai 200080China Department of Physiology School of Basic Medical SciencesWeifang Medical UniversityWeifangShandong 261021China Department of Thoracic Surgery Shanghai Chest HospitalShanghai Jiao Tong UniversityShanghai 200030China Department of molecular and Celular Biochemistry Markey Cancer CenterUniversity of Kentucky College of MedicineLexingtonKY40506USA Department of Respiratory Medicine The Second Affiliated HospitalDalian Medical UniversityDalianLiaoning116023China Peninsular Cancer Center Binzhou Medical UniversityYantaiShandong 264003China

Alcohol consumption contributes to global mortality and cancer ***(ACE),the oxidized metabolite of alcohol,is highly reactive towards DNA,resulting in DNA *** can be detoxified to acetate by acetaldehyde dehydrogenase... 详细信息

关键词： mortality damage ALDH2

Ultratough Yet Dynamic Crystalline Poly(thiourethane)Network Directly from Low Viscosity Precursors

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CCS chemistry 2024年第3期6卷 682-692页

作者： Haijun Feng Yi Sheng Guancong Chen Binjie Jin Zizheng fang Bo Yang Xiaorui zhou Wenxuan Wu Tao Xie Ning Zheng State Key Laboratory of Chemical Engineering College of Chemical and Biological EngineeringZhejiang UniversityHangzhou 310058 Department of Colorectal Surgery and Oncology Key Laboratory of Cancer Prevention and InterventionMinistry of EducationThe Second Affiliated HospitalZhejiang University School of MedicineHangzhou 310027

Thermosets based on direct curing of multifunctional monomers offer processing flexibility that thermoplastics cannot ***,this type of thermoset is typically amorphous since it is difficult to meet the stringent requirement of long-range molecular regularity for ***,we report here a crystallizable poly(thiourethane)thermoset synthesized directly from the curing of low-viscosity liquid precursors that does not employ any *** crystalline nature results in superior toughness,comparable to commercial high-density polyethylene,in sharp contrast to the brittleness of the typical,rigid,glassy thermoset *** that,the network polymer exhibits shape-memory behavior in which the crystalline transition is utilized for temporary shape fixing/recovery whereas the dynamic thiourethane bonds can be activated for bond exchange as a mechanism for complex shape *** with these combined features represent attractive options for demanding engineering applications due to their high performance and multifunctinality.

关键词： thermosets crystalline polymer thiourethane thermadapt

Rapid discovery of two unprecedented meroterpenoids from Daphne altaica *** molecular networking integrated with MolNetEnhancer and Network Annotation Propagation

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Chinese Chemical Letters 2024年第8期35卷 294-298页

作者： Wei-Yu zhou Zi-Han Xi Ning-Ning Du Li Ye Ming-Hao Jiang Jin-Le Hao Bin Lin Guo-Dong yao Xiao-Xiao Huang Shao-Jiang Song Key Laboratory of Computational chemistry-Based Natural Antitumor Drug Research&Development Liaoning ProvinceEngineering Research Center of Natural Medicine Active Molecule Research&DevelopmentLiaoning ProvinceKey Laboratory of Natural Bioactive Compounds Discovery&ModificationShenyangSchool of Traditional Chinese Materia Medic1Shenyang Pharmaceutical UniversityShenyang 110016China Key Laboratory of Structure-Based Drug Design and Discovery of Ministry of Education Shenyang Pharmaceutical UniversityShenyang 110016China Wuya college of Innovation Shenyang Pharmaceutical UniversityShenyang 110016China

Under the guidance of the approach which integrates molecular networking,MolNetEnhancer and Net-work Annotation Propagation(NAP),daphnaltaicanoids A and B(1 and 2.with unprecedented 9-oxa-tetracyclo[6.***.1.0^(2.6).0^(8,13)]pentadecane and tetracyclo[5.***.0.1^(2.5).2.(4,11)]tridecane central frameworks were iso-lated from Daphne altaica Pall.,representing two types of unparalleled meroterpenoid *** struc-tures were elucidated by extensive spectroscopic analysis,nuclear magnetic resonance(NMR)calcula-tions,DP4+analysis and electronic circular dichroism(ECD)*** plausible biosynthetic path-ways for 1 and 2.were ***,2.exerted potent neuroprotective activities which were su-perior to trolox at 12.5 and 2.μmol/***,1 and 2.exhibited more noticeable acetylcholinesterase inhibitory activities than *** docking simulations were performed to explore the inter-molecular interaction of compounds 1 and 2.with *** bioactivity evaluation results highlight the prospects of 1 and 2.as a novel category of neurological agents.

关键词： Daphne altaica Pall. molecular networking MolNetEnhancer NAP Unprecedented meroterpenoid frameworks Neuroprotective activities Acetylcholinesterase inhibitors