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Poly(L-lactide)-Poly(ethylene glycol) Multiblock Copolymers: Synthesis and Properties

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Chinese Chemical Letters 2002年第1期13卷 33-36页

作者： Wei Jun LUO Su Ming LI Jian Zhong BEI shen guo wang Center fpr Molecular Science Institute of ChemistryChinese Academy of SciencesBeijing 100080

Poly (L-lactide)-poly(ethylene glycol) multiblock copolymers with predetermined block lengths were synthesized by polycondensation of PLA diols and PEG diacids. These copolymers presented special properties, such as better miscibility between the two components, low crystallinity and better hydrophilicity, which can be modulated by adjusting the block lengths of the two components.

关键词： Poly (L-lactide) poly(ethylene glycol) biodegradability multiblock copolymer miscibility crystallinity hydrophilicity.

SYNTHESIS OF POLY(ETHYLENE TEREPHTHALATE)-POLYCAPROLACTONE BLOCK COPOLYMER BY DIRECT COPOLYMERIZATION

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Chinese Journal of Polymer Science 1999年第3期17卷 231-235页

作者： shen-guo wang Kai Tang Institute of Chemistry, Chinese Academy of Sciences, Beijing 100080, China Chinese Acad Sci Inst Chem Beijing 100080 Peoples R China

Po ly(ethylene terephthalate)-polycaprolactone block copolymer (PCL-b-PET) is a polyester with improved biodegradability. In the present paper, a new direct copolymerization method of epsilon-caprolactone (epsilon-CL) and bishydroxyethylene terephthalate (BHET) in the presence of Ti(OBu)(4) was proposed for the synthesis of PCL-b-PET. The PCL-b-PET copolymer was characterized by IR, GPC and H-1-NMR techniques, and the effects of synthesis conditions, such as temperature, reaction time and concentration of catalyst on the copolymerization were discussed.

关键词： poly(ethylene terephthalate)-polycaprolactone block copolymer direct copolymerization biodegradable polymer

Photodegradation Behavior of Polycaprolactone-Poly(ethylene glycol)Block Copolymer

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Chinese Chemical Letters 1999年第4期10卷 327-330页

作者： Jian Zhong BEI Xing Zhou HU Zhen Ming MA shen guo wang(Institute of Chemistry, Chinese Academy of Sciences, Beijing 100080) Chinese Acad Sci Inst Chem Beijing 100080 Peoples R China

The biodegradation behavior in vitro and in vivo of polycaprolactone-poly (ethylene glycol) block copolymer (PCE) was reported in detail. In this paper, photodegradation test of PCE was performed by exposure to UV light. The mechanical properties and the inherent viscosity of PCE samples which are subjected to photodegradation were determined. The experimental results indicated that poly (ethylene glycol) (PEO) segment in PCE copolymer is photosensitive. The photodegra-dation rate of the PCE was increased with increasing poly (ethylene glycol) content.

关键词： photodegradation polycaprolactone -poly (ethylene glycol)

A STUDY ON MULTIPLE METAL TO METAL BONDS IN TRANSITION METAL COMPLEXES

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结构化学 1988年第1期 29-35页

作者： wang Zhizhong shen Erzhong guo Chunxiao wang Liqun Institute of Theoretical Chemistry, Jilin University, Changchun

We report here the calculation on electronic structures of model compounds of dimetal tetracarboxylate M2(O2CH)4 (M=V, Cr, Mo) by means of a DPS8 computer CNDO program. On the basis of molecular orbital components and... 详细信息

关键词： CNDO 兀一 A STUDY ON MULTIPLE METAL TO METAL BONDS IN TRANSITION METAL COMPLEXES Cr

IPN's PVA AND ITS CELL GROWTH PROPERTY

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Chinese Chemical Letters 1991年第12期2卷 971-972页

作者： shen guo wang Institute of Chemistry Academia Sinica Beijing 100080, CHINA Shu Qin LIU, Makoto KODAMA Research Institute for Polymers Textiles Tsukuba, 305 JAPAN

6 kinds of IPN's PVA were synthesized by using different monomers of HEMA, MAA and MMA. The effect of adding polysaccharide was also studied. The cell growth on them were determined and compared. The results showed that the cell growth property of the IPN's PVA with hydrophobic monomer of MMA is better, and it can be improved further by adding hyaluronic acid.

关键词： IPN’s PVA AND ITS CELL GROWTH PROPERTY Poly PVA MMA ITS

Effects of Aluminum on ATPase Activity and Lipid Composition of Plasma Membranes from Wheat Roots

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Agricultural Sciences in China 2002年第3期1卷 285-290页

作者： HE Long-fei,LIU You-liang, shen Zhen-guo and wang Ai-qin(College of Agronomy, Guangxi University, Nanning 530005 Department of Agronomy, NanjingAgricultural University, Nanjing 210095) College of Agronomy Guangxi University Nanning 530005 Department of Agronomy Nanjing Agricultural University Nanjing 210095

The effects of aluminum on ATPase activity and lipid composition of the plasma membranes isolated from root tips of Al-tolerant (Altas 66) or Al-sensitive (Scout 66) cultivar of Triticum aestivum L. was assayed. The results showed that both cultivars had similar changes in H+-ATPase and Ca2+-ATPase activities after aluminum treatment. Exposure of both cultivars to 20 and 100 (mol/L aluminum for 5 d significantly decreased the activities of Ca2 + -ATPase of plasma membranes. The activities of H+-ATPase in plasma membrane increased under 20 μmol/L aluminum and decreased at 100 ***/L aluminum. With aluminum treatment, the PL content of plasma membrane decreased, but GL content increased. The ratio of PL to GL decreased more distinctly in Scout 66 than that in Altas 66. Treated with 20 and 100 μmol/L aluminum, linolenic acid content and the index of unsaturated fatty acids decreaced greatly in Scout 66, but the index of unsaturated fatty acids in Altas 66 increased slightly.

关键词： Aluminum stress H^+-ATPase Ca^(2+)-ATPase H^+-pump activity Lipids

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SiO_2气凝胶的常压制备及其热传输特性

同济大学学报（自然科学版） 2004年第8期32卷 1106-1110页

作者：沈军汪国庆王珏邓忠生同济大学物理系上海200092

以相对廉价的多聚硅 (E - 4 0 )为硅源 ,通过溶胶 -凝胶工艺制备了SiO2 气凝胶 .采用以三甲基氯硅烷(TMCS)为表面修饰剂 ,硅油为干燥介质的表面修饰工艺 ,实现了在常压条件下的制备 .气凝胶热导率的测试采用的是瞬态热线法 ,同时还采用B... 详细信息

以相对廉价的多聚硅 (E - 4 0 )为硅源 ,通过溶胶 -凝胶工艺制备了SiO2 气凝胶 .采用以三甲基氯硅烷(TMCS)为表面修饰剂 ,硅油为干燥介质的表面修饰工艺 ,实现了在常压条件下的制备 .气凝胶热导率的测试采用的是瞬态热线法 ,同时还采用BET(brunaner emmett teller)方法 ,对气凝胶的孔径等特性进行了测试 ,系统研究了密度、温度、气压、湿度及掺杂物等因素对材料导热性能的影响 .

关键词：二氧化硅气凝胶制备表面修饰热导率

Maintaining moderate levels of hypochlorous acid promotes neural stem cell proliferation and differentiation in the recovery phase of stroke

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Neural Regeneration Research 2025年第3期20卷 845-857页

作者： Lin-Yan Huang Yi-De Zhang Jie Chen Hai-Di Fan Wan wang Bin wang Ju-Yun Ma Peng-Peng Li Hai-Wei Pu Xin-Yian guo Jian-Gang shen Su-Hua Qi School of Medical Technology Xuzhou Key Laboratory of Laboratory DiagnosticsXuzhou Medical UniversityXuzhouJiangsu ProvinceChina School of Pharmacy Xuzhou Medical UniversityXuzhouJiangsu ProvinceChina Department of Laboratory Medicine Branch Hospital of Huai’an First People’s HospitalHuai’anJiangsu ProvinceChina Department of Laboratory Medicine the Affiliated Hospital of Xuzhou Medical UniversityXuzhouJiangsu ProvinceChina School of Chinese Medicine The University of Hong KongHong Kong Special Administrative RegionChina

It has been shown clinically that continuous removal of ischemia/reperfusion-induced reactive oxygen species is not conducive to the recovery of late ***,previous studies have shown that excessive increases in hypochlorous acid after stroke can cause severe damage to brain *** previous studies have found that a small amount of hypochlorous acid still exists in the later stage of stroke,but its specific role and mechanism are currently *** simulate stroke in vivo,a middle cerebral artery occlusion rat model was established,with an oxygen-glucose deprivation/reoxygenation model established in vitro to mimic *** found that in the early stage(within 24 hours)of ischemic stroke,neutrophils produced a large amount of hypochlorous acid,while in the recovery phase(10 days after stroke),microglia were activated and produced a small amount of hypochlorous ***,in acute stroke in rats,hypochlorous acid production was prevented using a hypochlorous acid scavenger,taurine,or myeloperoxidase inhibitor,4-aminobenzoic acid *** results showed that high levels of hypochlorous acid(200μM)induced neuronal apoptosis after oxygen/glucose deprivation/***,in the recovery phase of the middle cerebral artery occlusion model,a moderate level of hypochlorous acid promoted the proliferation and differentiation of neural stem cells into neurons and *** suggests that hypochlorous acid plays different roles at different phases of cerebral ischemia/reperfusion *** levels of hypochlorous acid(5 and 100μM)promoted nuclear translocation ofβ-*** transfection of single-site mutation plasmids,we found that hypochlorous acid induced chlorination of theβ-catenin tyrosine 30 residue,which promoted nuclear ***,our study indicates that maintaining low levels of hypochlorous acid plays a key role in the recovery of neurological function.

关键词： cell differentiation cerebral ischemia/reperfusion injury chlorination hypochlorous acid microglia neural stem cell neurogenesis nuclear translocation stroke β-catenin

A Rapid Adaptation Approach for Dynamic Air‑Writing Recognition Using Wearable Wristbands with Self‑Supervised Contrastive Learning

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Nano-Micro Letters 2025年第2期17卷 417-431页

作者： Yunjian guo Kunpeng Li Wei Yue Nam‑Young Kim Yang Li guozhen shen Jong‑Chul Lee Department of Electronic Convergence Engineering Kwangwoon UniversitySeoul 01897South Korea Radio Frequency Integrated Circuit(RFIC)Bio Centre Kwangwoon UniversitySeoul 01897South Korea Department of Electronic Engineering Kwangwoon UniversitySeoul 01897South Korea School of Microelectronics Shandong UniversityJinan 250101People’s Republic of China State Key Laboratory of Integrated Chips and Systems Fudan UniversityShanghai 200433People’s Republic of China School of Integrated Circuits and Electronics Beijing Institute of TechnologyBeijing 100081People’s Republic of China

Wearable wristband systems leverage deep learning to revolutionize hand gesture recognition in daily *** existing approaches that often focus on static gestures and require extensive labeled data,the proposed wearable wristband with selfsupervised contrastive learning excels at dynamic motion tracking and adapts rapidly across multiple *** features a four-channel sensing array composed of an ionic hydrogel with hierarchical microcone structures and ultrathin flexible electrodes,resulting in high-sensitivity capacitance *** wireless transmission from a Wi-Fi module,the proposed algorithm learns latent features from the unlabeled signals of random wrist ***,only few-shot labeled data are sufficient for fine-tuning the model,enabling rapid adaptation to various *** system achieves a high accuracy of 94.9%in different scenarios,including the prediction of eight-direction commands,and air-writing of all numbers and *** proposed method facilitates smooth transitions between multiple tasks without the need for modifying the structure or undergoing extensive task-specific *** utility has been further extended to enhance human–machine interaction over digital platforms,such as game controls,calculators,and three-language login systems,offering users a natural and intuitive way of communication.

关键词： Wearable wristband Self-supervised contrastive learning Dynamic gesture Air-writing Human-machine interaction