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Chemical Research in Chinese Universities 2007年第1期23卷 31-34页

作者： LUE Chun-sheng zhang yue-tao MU Ying Key Laboratory for Supramolecular Structure and Materials of Ministry of Education School of Chemistry Jilin University 130012 P. R. China Department of Chemical Engineering Daqing Petroleum Institute Daqing 161310 P. R. China

The copolymerization of ethylene with dieyclopentadiene （DCP） in the presence of a constrained geometry tetramethylcyclopentadi-enyl-phenoxytitanium catalyst [ 2,4-＇ Bu2-6-（ 2,3,4,5-Me4 -Cp ） -PhO ] TICl2, combined with AI（ iBu）3/Ph3C^＋ B（ CsF5 ）4^- cocatalyst system was studied. The copolymers that were formed were characterized by ＇ H and ,3 C NMR, differential scanning calorimetry （ DSC）, SEM, and X-ray diffraction （XRD） analyses. The re- suits of the analysis indicate that the copolymers of ethylene with dicyclopentadiene are amorphous and display two or more melting temperatures in their DSC diagrams. Moreover, the morphologies of the copolymers are quite different from that of polyethylenes.

关键词： Ethylene polymerization Dicyclopentadiene Copolymers Metalloeene Polyethylene

Effects of penehyclidine hydrochloride in small intestinal damage caused by limb ischemia-reperfusion

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World Journal of Gastroenterology 2011年第2期17卷 254-259页

作者： Yan zhang Yu-Fang Leng Xing Xue yue zhang tao Wang Yu-Qing Kang Department of Anesthesiology First HospitalLanzhou University Lanzhou 730000 Gansu Province China

AIM:To investigate the protective effect of penehyclidine hydrochloride post-conditioning in the damage to the barrier function of the small intestinal mucosa caused by limb ischemia-reperfusion(LIR) injury. METHODS:Male Wistar rats were randomly divided into three groups(36 rats each) :the sham-operation group(group S) ,lower limb ischemia-reperfusion group(group LIR) ,and penehyclidine hydrochloride postconditioning group(group PHC) .Each group was divided into subgroups(n=6 in each group) according to ischemic-reperfusion time,*** 0 h(T1) ,1 h(T2) ,3 h(T3) ,6 h(T4) ,12 h(T5) ,and 24 h(T6) .Bilateral hind-limb ischemia was induced by rubber band application proximal to the level of the greater trochanter for 3 *** group PHC,0.15 mg/kg of penehyclidine hydrochloride was injected into the tail vein immediately after 3 h of bilateral hind-limb *** designated rats were sacrificed at different time-points of reperfusion;diamine oxidase(DAO) ,superoxide dismutase(SOD) activity,myeloperoxidase(MPO) of small intestinal tissue,plasma endotoxin,DAO,tumor necrosis factor-α(TNF-α) ,and interleukin(IL) -10 in serum were detected in the rats. RESULTS:The pathological changes in the small intestine were observed under light *** levels of MPO,endotoxin,serum DAO,and IL-10 at T1-T6,and TNF-αlevel at T1-T4 increased in groups LIR and PHC(P<0.05) compared with those in group S,but tissue DAO and SOD activity at T1-T6 decreased(P<0.05) .In group PHC,the tissue DAO and SOD activity at T2-T6,and IL-10 at T2-T5 increased to higher levels than those in group LIR(P<0.05) ;however,the levels of MPO,endotoxin,and DAO in the blood at T2-T6,and TNF-αat T2 and T4 decreased(P<0.05) . CONCLUSION:Penehyclidine hydrochloride post-conditioning may reduce the permeability of the small intestines after *** protection mechanisms may be related to inhibiting oxygen free radicals and inflammatory cytokines for organ damage.

关键词： Penehyelidine hydrochloride Post-conditioning Limb ischemia-reperfusion injury Small intestine Protection

Sythesis, Characterization and Catalysis of [ η~5,η~1-C_5H_4-CHPh-PhO]TiCl_2

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Chemical Research in Chinese Universities 2001年第1期17卷 115-116页

作者： WANG Jian hui MU Ying PU Wei ming zhang yue tao YANG Guang di LIU Ju zheng Department of Chemistry Jilin UniversityChangchun 130023P.R.China

The synthesis and structure of phenol groups containing ligand 2-[(cyclopentadienyl-phenyl)-methyl]phenol(CpH-PhCH-PhOH) were described. H Nuclear magnetic resonance (NMR) was used to show existence of ligand precursor in isomers of the group. Me3SiCp-PhCH-PhOSiMe3 was formed via treatment of 2 mol Me3SiCl with the dilithium salt of the ligand. New Ti compound [η+5, η1-C5H4-PhCH-PhO]TiCl2 was formed by reacting with titanium chloride.

关键词： Metallocene Catalyst Cyclopentadienyl group

An efficient synthesis of 1,5-benzodiazepine derivatives catalyzed by boric acid

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Chinese Chemical Letters 2009年第8期20卷 905-908页

作者： Xin Zhou Mei yue zhang Shu tao Gao Jing Jun Ma Chun Wang Chao Liu Hebei Key Laboratory of Bioinorganic Chemistry College of Sciences Agricultural University of Hebei Baoding 071001 China

1,5-Benzodiazepine derivatives have been synthesized by the condensation of o-phenylenediamines and ketones in the presence of boric acid as catalyst under mild conditions. This method is simple, environmentally benign and high yielding. ？2009 Chun Wang. Published by Elsevier B.V. on behalf of Chinese Chemical Society. All rights reserved.

关键词： 1,5-Benzodiazepincs o-Phenylenediamines Boric acid Synthesis

Physics based circuit compatible model for hybrid antiferroelectric random access memory

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Science China(Information Sciences) 2025年第1期68卷 396-397页

作者： Qiuxia WU yue PENG Wenwu XIAO Wenxuan MA Shuo zhang Litao SUN Chunfu zhang Xiaohua MA yue HAO School of Microelectronics Xidian University Xi'an Uni IC Semiconductors

Since the discovery of HfO2-based ferroelectric （FE） materials in 2011,considerable advancements have been made in material preparation,mechanism research,and device realization [1].Consequently,these materials are now regarded as leading candidates for embedded non-volatile memory（eNVM）.Beyond eNVM applications,recent studies have demonstrated that memory devices with antiferroelectric（AFE） films can achieve high response speeds,low latency,and reduced power consumption while maintaining excellent endurance characteristics [2,3].Additionally,the typical double hysteresis loops and multiple non-overlapping polarization current peaks of AFE films offer a novel approach to designing multistate ***,in order to further promote the application of high storage density AFE,an AFRAM electronic design automation （EDA） model must be developed,and it has yet to be proposed.

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Efficient photocatalytic reduction of CO2 to formate by a molecular noble metal-free system

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Science China Chemistry 2025年第1期68卷 152-156页

作者： Lihua zhang Lingjing Chen Huatian Shi yue Wei Gui Chen Tai-Chu Lau School of Environment and Civil Engineering Research Center for Eco-environmental Engineering Dongguan University of Technology Department of Chemistry and Institute of Molecular Functional Materials City University of Hong Kong

Reducing CO2to carbon-neutral solar fuels can not only alleviate the energy demand but also mitigate the greenhouse *** present,developing an efficient non-noble metal photo/electrocatalytic system for converting CO2to a specific product beyond CO is still a big ***,we report a new cobalt complex bearing 2,2′-bi-1,10-phenanthroline ligand that can photocatalytically reduce CO2to formate （HCOO-）.Turnover number （TON） for HCOO-up to 677 with 99%selectivity can be achieved using organic dyes purpurin as photosensitizer and 1,3-dimethyl-2-phenyl-2,3-dihydro-1H-benzo[d]imidazole （BIH） as sacrificial reductant in a CO2-saturated NMP/TEA （v/v,3:1） solution under visible light *** potential electrolysis at-1.41 V （***/Ag Cl） in the presence of 12 m M Et3NHBF4also produced HCOO-with Faradaic efficiency of 39%.Spectroscopic and electrochemical studies suggest that a[CoI-H]species is the key intermediate for CO2reduction.

关键词： photocatalysis noble metal-free CO2 reduction formate cobalt hydride

Propagating subduction initiation of the Caroline Plate at the Mussau Trench

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Science China Earth Sciences 2025年第1期68卷 253-269页

作者： Chun-Feng LI Yongkang DENG tao WU Dongdong DONG Guoliang zhang Jiazheng zhang Yutao LIU Yaqing LI Fugui TANG Lulu zhang Department of Marine Sciences Zhejiang University Laboratory of Marine Mineral Resources Laoshan Laboratory Key Lab of Marine Geology and Environment Institute of Oceanology Chinese Academy of Sciences Key Lab of Ocean and Marginal Sea Geology South China Sea Institute of Oceanology Chinese Academy of Sciences Science & Technology on Integrated Information System Lab Institute of Software Chinese Academy of Sciences

New seismic imaging from the Mussau Trench confirms that, under horizontal compression on an oceanic plate boundary, it is within the young and weak oceanic plate that a trench will develop, and it is the young plate, not so long after its birth, that starts to subduct toward the old plate. The Mesozoic Pacific Plate cannot easily bend, under the joint horizontal compression and vertical gravity pull, even with a pre-existing weak zone in place and with a large age offset across the plate boundary. The bending of the Caroline Plate near the northern end of the Mussau Trench started only after a long-time span of trench migration, and/or after a prolonged transition from initial compression to trench development. Highly contrasting trench deformation and sedimentary accretion between two parallel seismic sections support an evident migration of underthrusting or significant longitudinal heterogeneity along the trench. The swift transition from underthrusting to non-thrusting can be explained by a counter-clockwise rotation of the Caroline Plate. That miniature accretionary wedges develop even before the subduction initiates imply strong compression and uplifting before the underthrusting can kick-start. Rotation of the Caroline Plate have been halted as the Mussau Trench is seismically rather quiet and the Lyra Trough to the east shows relaxational extension.

关键词： Mussau Trench Subduction initiation Seismic reflection Caroline Plate

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四甲基环戊二烯基苯氧基二氯化钛衍生物的合成及催化烯烃聚合研究

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高等学校化学学报 2005年第3期26卷 571-574页

作者：张越涛母瀛吕春胜张帆陈丛喜吉林大学化学学院超分子结构与材料教育部重点实验室长春130012

4-R1 -6-R-2 -Me4 Cp H-Ph OH[R1 =t Bu,R=t Bu(1 ) ;R1 =H,R=t Bu(2 ) ,Ph(3 ) ,Me(4 ) ]经双三甲基硅基化后与 Ti Cl4 反应 ,合成了 4种限制几何构型茂金属催化剂 4-R1 -6-R-2 -Me4 Cp-Ph OTi Cl2 [R1 =t Bu,R=t Bu(5 ) ;R1 =H,R=t Bu(6) ,Ph(7) ,Me(8) ],合成产率有较大提高 .这些茂金属化合物经过 i Bu3Al和Ph3C+ B(C6 F5) - 4活化后对乙烯聚合有很好的催化活性 ,并生成乙基支化聚乙烯 .考察了催化剂结构与活性的关系以及聚合反应条件对催化剂性能的影响。

关键词：茂金属催化剂烯烃聚合反应单茂钛化合物均相催化

The shifts of precipitation phases and their impacts

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Science China Earth Sciences 2025年

作者： Xuemei LI tao CHE Yuanlong TANG Huan'e DUAN Guigang WANG Xu zhang Chuanming YANG Jun WU yue zhang Lanhai LI Faculty of Geomatics Lanzhou Jiaotong University National-Local Joint Engineering Research Center of Technologies and Applications for National Geographic State Monitoring Key Laboratory of Science and Technology in Surveying & Mapping Gansu Province Key Laboratory of Cryospheric Science and Frozen Soil Engineering Heihe Remote Sensing Experimental Research StationNorthwest Institute of Eco-Environment and Resources Chinese Academy of Sciences Xinjiang Key Laboratory of Water Cycle and Utilization in Arid Zone Xinjiang Institute of Ecology and Geography Chinese academy of Sciences Tianshan Snow Cover and Avalanche Observation and Research Station of Xinjiang

Precipitation comes in various phases, including rainfall, snowfall, sleet, and hail. Shifts of precipitation phases, as well as changes in precipitation amount, intensity, and frequency, have significant impacts on regional climate, hydrology,ecology, and the energy balance of the land-atmosphere system. Over the past century, certain progress has been achieved in aspects such as the observation, discrimination, transformation, and impact of precipitation phases. Mainly including:since the1980s, studies on the observation, formation mechanism, and prediction of precipitation phases have gradually received greater attention and reached a certain scale. The estimation of different precipitation phases using new detection theories and methods has become a research focus. Avariety of discrimination methods or schemes, such as the potential thickness threshold method of the air layer, the temperature threshold method of the characteristic layer, and the near-surface air temperature threshold method,have emerged one after another. Meanwhile, comparative studies on the discrimination accuracy and applicability assessment of multiple methods or schemes have also been carried out simultaneously. In recent years, the shift of precipitation from solid to liquid (SPSL) in the mid-to-high latitudes of the Northern Hemisphere has become more pronounced due to global warming and human activities. It leads to an increase in rain-on-snow (ROS) events and avalanche disasters, affecting the speed, intensity, and duration of spring snow-melting, accelerating sea ice and glacier melting, releasing carbon from permafrost, altering soil moisture, productivity, and phenological characteristics of ecosystems, and thereby affecting their structures, processes, qualities, and service functions. Although some progress has been made in the study of precipitation phases, there remains considerable research potential in terms of completeness of basic data, reliability of discrimination schemes,

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长短期融资对产业选择的影响:中国台湾和韩国的比较

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上海金融 2012年第1期 92-96页

作者：陈磊张涛乐文平上海海事大学经济与管理学院复旦大学经济学院

20世纪70年代,中国台湾和韩国均实行'重化工业化(HCI Drive)'政策,台湾的效果不明显,韩国却取得了成功。本文通过考察两经济体在该时期制造业内部产业结构的变化,并比较台湾与韩国企业融资期限的差异,解释了台湾与韩国实行'重化工业化'... 详细信息

20世纪70年代,中国台湾和韩国均实行'重化工业化(HCI Drive)'政策,台湾的效果不明显,韩国却取得了成功。本文通过考察两经济体在该时期制造业内部产业结构的变化,并比较台湾与韩国企业融资期限的差异,解释了台湾与韩国实行'重化工业化'结果的不同。我们认为,两经济体中政府对金融资源分配的干预角色以及企业规模的差异,影响了企业的融资决策,从而影响了整个经济对产业的选择。

关键词：长短期融资产业选择重化工业化