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Chinese Journal of Polymer Science 2006年第1期24卷 21-27页

作者： Xi-jie Liu Jun-quan Sun hai-ying zhang Xiao-hui Xiao and Feng Lin Department of Chemical Engineering,College of Material and Chemical Engineering,Zhejiang University,Hangzhou 310027,China Department of Chemical Engineering College of Material and Chemical Engineering Zhejiang University Hangzhou 310027 China

By treating disodium（thiophenedimethylene）dicyclopentadienide C4H2S（CH2C5H4Na）2 with two equivalent of CpTiCl3 or CpZrC13 DME at 0℃ in THF, two new thiophenedimethylene bridged binuclear metallocenes [Cl2MC5H5][C5H4CH2C4H2SCH2C5H4][C5H5MCl2] （M = Ti 3, M = Zr 4） were synthesized in high yield and their structures were characterized by ^1H-NMR. These complexes were used as catalysts for ethylene polymerization in the presence of methylaluminoxane （MAO）. The effects of polymerization temperature, time, concentration of catalyst, molar ratio of MAO/Cat on polymerization were studied in detail. The catalytic activities of thiophenedimethylene bridged binuclear metallocene catalysts （3, 4） reached 2.44 × 10^5 g PE mol^-1 cat^-1· h^-1, 9.61 × 10^5 g PE mol^-1 · cat^-1· h^-1 respectively, which are higher than that of pheneyldimethylene bridged binuclear metallocene catalysts and much higher than that of corresponding mononuclear metallocenes （Cp2TiCl2 and Cp2ZrCl2）. The molecular weight distribution curves of polyethylenes produced by binuclear metallocene catalysts （3, 4） and by mononuclear metallocene catalyst have only single peak, but the former （MWD = 3.5-4.7） is obviously broader than the latter （MWD = 2.0-2.2）.

关键词： Binuclear metallocene Thiophenedimethylene bridged Ethylene polymerization.

Neuroprotective effects of insulin-like growth factor-2 in 6-hydroxydopamine-induced cellular and mouse models of Parkinson’s disease

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Neural Regeneration Research 2023年第5期18卷 1099-1106页

作者： hai-ying zhang Yong-Cheng Jiang Jun-Rui Li Jia-Nan Yan Xin-Jue Wang Jia-Bing Shen Kai-Fu Ke Xiao-Su Gu Department of Neurology Affiliated Hospital of Nantong UniversityNantongJiangsu ProvinceChina Research Center of Clinical Medicine Affiliated Hospital of Nantong UniversityNantongJiangsu ProvinceChina Department of Clinical Medicine The First Clinical Medical College of Xuzhou Medical UniversityXuzhouJiangsu ProvinceChina

Skin-derived precursor Schwann cells have been reported to play a protective role in the central nervous system. The neuroprotective effects of skin-derived precursor Schwann cells may be attributable to the release of growth factors that nourish host cells. In this study, we first established a cellular model of Parkinson’s disease using 6-hydroxydopamine. When SH-SY5 Y cells were pretreated with conditioned medium from skin-derived precursor Schwann cells, their activity was greatly increased. The addition of insulin-like growth factor-2 neutralizing antibody markedly attenuated the neuroprotective effects of skin-derived precursor Schwann cells. We also found that insulin-like growth factor-2 levels in the peripheral blood were greatly increased in patients with Parkinson’s disease and in a mouse model of Parkinson’s disease. Next, we pretreated cell models of Parkinson’s disease with insulin-like growth factor-2 and administered insulin-like growth factor-2 intranasally to a mouse model of Parkinson’s disease induced by 6-hydroxydopamine and found that the level of tyrosine hydroxylase, a marker of dopamine neurons, was markedly restored, α-synuclein aggregation decreased, and insulin-like growth factor-2 receptor downregulation was alleviated. Finally, in vitro experiments showed that insulin-like growth factor-2 activated the phosphatidylinositol 3 kinase(PI3 K)/AKT pathway. These findings suggest that the neuroprotective effects of skin-derived precursor Schwann cells on the central nervous system were achieved through insulinlike growth factor-2, and that insulin-like growth factor-2 may play a neuroprotective role through the insulin-like growth factor-2 receptor/PI3 K/AKT pathway. Therefore, insulin-like growth factor-2 may be an useful target for Parkinson’s disease treatment.

关键词： 6-hydroxydopamine alpha-synuclein insulin-like growth factor-2 receptor insulin-like growth factor-2 neurodegeneration neuroprotection Parkinson’s disease skin-derived precursor Schwann cells

The protective effect and underlying mechanism of hainan papaya water extract against neuronal apoptosis induced by A β 40

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Asian Pacific Journal of Tropical Medicine 2016年第7期9卷 653-658页

作者： Jiu-Hong Zhao hai-ying zhang Xian-Fang zhang Xu Dong Qi-Bing Liu Yue-Li Liu Yi-Di Huang Quan-Peng zhang Gang Luo Zhi-Jian Ma Xi-Nan Yi Department of Anatomy Hainan Medical College Neuroscience Research Institute Hainan Medical College School of Pharmacy Hainan Medical College

Objective:To investigate whether hainan papayas has protective effects in an Aimary neuron injury model and elucidate the underlying molecular mecha β 40-induced ***:Cultured primary neurons from the dorsal root ganglia(DRG) of Sprague-Dawley(SD) rats were treated with 20 μM A culture medium β 40 peptide,100 μg/L hainan papaya water extract,peptide plus extract,or for 24 *** viability was measured by MTT assay,and neuronal apoptosis was evaluated by DAPI *** signaling pathway-associated molecule activation and changes in Bax expression were analyzed by Western blotting and ***:A cell viability rate of(44.11±6.59)% in the Ading different concentrations of the extract β 40 group was rescued to(79.13±6.64)% by *** showed pyknotic nuclei in 39.5% of A β 40-treated cells;the fraction dropped to 17.4% in the 100 μg/L extract *** phosphorylation was observed in the Aent with 100 μg/L *** papaya water ex β 40 group but was ameliorated by pretreatmtract also prevented Ation of MEK,RSK1 and CREB associated with ERK signaling and d β 40-induced phosphorylaownregulated Bax expression in the ***:The resultss suggest that hainan papaya water extract has protective effects on neurons;the mechanism may be related to suppression of ERK signaling activation.

关键词： A β peptide Neuron protection ERK signaling pathway

Dimensional regulation in gigantic molybdenum blue wheels featuring{(W)Mo_(5)}motifs for enhanced proton conductivity

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Nano Research 2024年第9期17卷 8261-8268页

作者： Yu-Lun Wu Jing Du hai-ying zhang Ming-Jun Hou Qiao-Yue Li Wei-Chao Chen Kui-Zhan Shao Bo Zhu Chao Qin Xin-Long Wang Zhong-Min Su Key Laboratory of Polyoxometalate and Reticular Material Chemistry of Ministry of Education Department of ChemistryNortheast Normal UniversityChangchun 130024China Hebei Key Laboratory of Organic Functional Molecules National Demonstration Center for Experimental Chemistry EducationTesting and Analysis CenterCollege of Chemistry and Materials ScienceHebei Normal UniversityShijiazhuang 050024China State Key Laboratory of Supramolecular Structure and Materials Institute of Theoretical ChemistryCollege of ChemistryJilin UniversityChangchun 130021China

Dimensional regulation in polyoxometalates is an effective strategy during the design and synthesis of polyoxometalates-based high proton conductors,but it is not available to ***,the precise regulation of dimensionality has been realized in an unprecedented gigantic molybdenum blue wheel family featuring pentagonal{(W)Mo5}motifs through optimizing the molar ratio of Mo/W,including[Gd_(2)Mo_(124)W_(14)O_(422)(H_(2)O)62]38-(0D-{Mo_(124)W_(14)},1),[Mo_(126)W_(14)O441(H_(2)O)51]^(70-)(1D-{Mo_(126)W_(14)}n,2),and[Mo_(124)W_(14)O_(430)(H_(2)O)50]60-(2D-{Mo_(124)W_(14)}n,3).Such important{(W)Mo5}structural motif brings new reactivity into gigantic Mo blue *** are different numbers and sites of{Mo2}defects in each wheel-shaped monomer in 1-3,which leads to the monomers of 2 and 3 to form 1D and 2D architectures via Mo-O-Mo covalent bonds driven by{Mo2}-mediated H_(2)O ligands substitution process,respectively,thus achieving the controllable dimensional *** expected,the proton conductivity of 3 is 10 times higher than that of 1 and 1.7 times higher than that of *** continuous proton hopping sites in 2D network are responsible for the enhanced proton conductivity with lower activation *** study highlights that this dimensional regulation approach remains great potential in preparing polyoxometalates-based high proton conductive materials.

关键词： polyoxometalate molybdenum blue wheels Mo/W mixed-addenda polyoxometalates dimensional regulation proton conduction

Oxygen vacancies enriched Ir/WOx catalysts for the directly chem-catalytic conversion of cellulose to ethanol

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Tungsten 2025年第1期7卷 88-99页

作者： Yu-Jing Weng Zhao-ying Ding ying-Chao Li Yuan-Feng Wu Yuan-Yang Xu Rui Chen Xiao-Lei Zhao hai-Yong Wang Da-Lei zhang Yu-Long zhang Henan Key Laboratory of Coal Green Conversion and International Joint Laboratory of Coal Clean Utilization College of Chemistry and Chemical Engineering Henan Polytechnic University Key Laboratory of Renewable Energy Guangzhou Institute of Energy Conversion Chinese Academy of Sciences Liaoning Institute of Energy Technology

Tungsten and its oxides are highly versatile catalysts with unique properties that hold great promise for a wide array of applications,including biological pathways and chemical *** chemo-catalysis of cellulose to ethanol presents a promising avenue for ethanol synthesis with the potential for enhanced efficiency compared to conventional methods,offering a sustainable and carbon-neutral alternative to existing petrochemical and biological ***,Ir/WOxcatalysts enriched with oxygen vacancies were meticulously prepared and demonstrated remarkable catalytic performance in converting cellulose to ethanol directly in the presence of tungstic *** catalyst achieved a high ethanol yield of 66.5%under optimal reaction conditions,approaching the theoretical yield limit of traditional ethanol *** results revealed the presence of oxygen defects,Bronsted/Lewis acidity,and Ir nanoclusters on the catalyst surface,working synergistically to facilitate the cascade catalysis of cellulose hydrolysis,sugar retro-aldol condensation reaction,and C2 intermediate hydrodeoxygenation to *** situ Fourier transform infrared spectrometer analysis confirmed the catalyst's ability to enhance the adsorption and activation of ethylene glycol for ethanol *** manipulating subtle structural features,this study offers a fresh perspective on tungsten group catalyst design and underscores the importance of synergistic effects among catalytic sites for the efficient production of ethanol from cellulose.

关键词： Cellulosic ethanol Chem-catalysis Hydrogenolysis Retro-aldol condensation Tungsten

Advanced Space-based Solar Observatory(ASO-S):an overview

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Research in Astronomy and Astrophysics 2019年第11期19卷 3-10页

作者： Wei-Qun Gan Cheng Zhu Yuan-Yong Deng Hui Li Yang Su hai-ying zhang Bo Chen Zhe zhang Jian Wu Lei Deng Yu Huang Jian-Feng Yang Ji-Jun Cui Jin Chang Chi Wang Ji Wu Zeng-Shan Yin Wen Chen Cheng Fang Yi-Hua Yan Jun Lin Wei-Ming Xiong Bin Chen hai-Chao Bao Cai-Xia Cao Yan-Ping Bai Tao Wang Bing-Long Chen Xin-Yu Li Ye zhang Li Feng Jiang-Tao Su ying Li Wei Chen You-Ping Li ying-Na Su hai-Yan Wu Mei Gu Lei Huang Xue-Jun Tang Key Laboratory of Dark Matter and Space Astronomy Purple Mountain ObservatoryChinese Academy of SciencesNanjing 210034China Innovation Academy for Microsatellites Chinese Academy of SciencesShanghai 201203China National Astronomical Observatories Chinese Academy of SciencesBeijing 100101China Nanjing Institute of Astronomical Optics&Technology National Astronomical ObservatoriesChinese Academy of SciencesNanjing 210042China Changchun Institute of Optics Fine Mechanics and PhysicsChangchun 130033China Xi’an Institute of Optics and Precision Mechanics Chinese Academy of SciencesXi’an 710119China National Space Science Center Chinese Academy of SciencesBeijing 100190China School of Astronomy and Space Science Nanjing UniversityNanjing 210023China Yunnan Observatories Chinese Academy of SciencesKunming 650011China School of Astronomy and Space Science University of Chinese Academy of SciencesBeijing 101408China Beijing Special Engineering and Design Institute Beijing 100028China Beijing Institute of Tracking and Telecommunications Technology Beijing 100094China Shanghai Academy of Spaceflight Technology Shanghai 201109China

The Advanced Space-based Solar Observatory(ASO-S)is a mission proposed for the 25 th solar maximum by the Chinese solar *** scientific objectives are to study the relationships between the solar magnetic field,solar flares and coronal mass ejections(CMEs).Three payloads are deployed:the Full-disk vector Magneto Graph(FMG),the Lyman-αSolar Telescope(LST)and the Hard X-ray Imager(HXI).ASO-S will perform the first simultaneous observations of the photospheric vector magnetic field,non-thermal imaging of solar flares,and the initiation and early propagation of CMEs on a single ***-S is scheduled to be launched into a 720 km Sun-synchronous orbit in *** paper presents an overview of the mission till the end of Phase-B and the beginning of Phase-C.

关键词： space vehicles instruments-Sun magnetic fields-Sun flares-Sun CMEs-Sun UV radiation-Sun X-ray,gamma-rays

b→ssin a Vector Quark Model

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Communications in Theoretical Physics 2005年第11期44卷 887-890页

作者： CAI hai-ying zhang Da-Xin Institute of Theoretical Physics,School of Physics,Peking University,Beijing 100871,China

The rare decay b→ss(?) is studied in a vector quark model by adding the contributions from exoticvector-like *** find that the contribution from box diagrams amounts to 10-9in the branching ratio,while theZ-mediated ... 详细信息

关键词： rare decay vector-like quarks

Design of the Full-disk Magneto Graph (FMG) onboard the ASO-S

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Research in Astronomy and Astrophysics 2019年第11期19卷 11-22页

作者： Yuan-Yong Deng hai-ying zhang Jian-Feng Yang Fu Li Jia-Ben Lin Jun-Feng Hou Zhen Wu Qian Song Wei Duan Xian-Yong Bai Dong-Guang Wang Juan Lv Wei Ge Jia-Ning Wang Zhao-ying Zheng Chen-Jie Wang Nan-Ge Wang Hou-Kun Ni Yi-Zhong Zeng Yang zhang Xiao Yang ying-Zi Sun Zhi-Yong zhang Xiao-Fan Wang Key Laboratory of Solar Activity National Astronomical ObservatoriesChinese Academy of SciencesBeijing 100101China Nanjing Institute of Astronomical Optics&Technology Chinese Academy of SciencesNanjing 210042China Xi’an Institute of Optics and Precision Mechanics Chinese Academy of SciencesXi’an 710119China School of Astronomy and Space Science University of Chinese Academy of SciencesBeijing 101408China

The Full-disk Magneto Graph(FMG),a payload onboard the Advanced Space Solar Observatory(ASO-S),will measure the vector magnetic field in the *** instrument consists of a frontwindow filter,a telescope,an LCVR polarimeter,an image-stabilization system,a seven-stage tunable Lyot filter,a CMOS camera with 4096×4096 pixels and a pair of calibration/focus *** this paper,we describe the design of the FMG instrument and provide a summary of test observations carried out with the FMG prototype.

关键词： Sun magnetic fields-space vehicles instruments-methods observational-techniques polarimetric

A frozen-thawed embryo transfer program improves the embryo utilization rate

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Chinese Medical Journal 2009年第17期122卷 1974-1978页

作者： ZHOU Feng LIN Xiao-na TONG Xiao-mei LI Chao LIU Liu JIN Xiao-ying ZHU hai-yan zhang Song-ying Assisted Reproduction Unit Department of Obstetrics andGynecology Sir Run Run Shaw Hospital Zhejiang UniversitySchool of Medicine Hangzhou Zhejiang 310016 China

Background Frozen-thawed embryo transfer （FET） is the most common way to prevent serious late ovarian hyperstimulation syndrome and increase the cumulative pregnancy rate. We evaluated the effectiveness of an FET program for improving the embryo implantation and clinical pregnancy rates, and ultimate embryo utilization rate in infertility treatment. Methods Patients undergoing in vitro fertilisation （IVF） cycles from January 2006 to June 2008 were enrolled, including 179 patients who had undergone the first FET cycle after controlled ovarian hyperstimulation （COH） in which all embryos were frozen （group C1） and 1306 patients who had COH with fresh embryo transfer （ET）（group T1）. Logistic regression was used to model the embryo implantation and clinical pregnancy rates based on the mother＇s age, numbers of oocytes retrieved, embryos transferred and high-quality embryos transferred. The embryo implantation and clinical pregnancy rates were also compared between two groups after adjusting for age, the numbers of oocytes retrieved and the numbers of embryos transferred. Results Logistic regression analysis confirmed that embryo implantation and clinical pregnancy rates in group C1 were both significantly higher than those in group T1 after adjusting for confounding factors （43.6% vs 29.0%, 63.1% vs 47.0%, respectively; P 〈0.01）. The embryo implantation and clinical pregnancy rates were consistently higher in group C1 by comparing the age groups ≥35 or 〈35 years. The clinical pregnancy rates for the numbers of oocytes retrieved per cycle being ≥15 or 〈15 were higher in group C1, as was the embryo implantation rate. These differences were statistically significant for oocyte numbers 〉15 （P 〈0.05）. The embryo implantation and clinical pregnancy rates in group C1 were both significantly higher than in group T1 when two or three embryos were transferred （P 〈0.05）. Conclusion A program of freezing all embryos and performing FET improved the rates of embryo implantation and c

关键词： embryo frozen-thawed embryo transfer pregnancy rate endometrial receptivity

Visible-light-responsive homologous heterostructure of oxynitrides constructed to boost charge separation and water splitting

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Science China Chemistry 2025年第1期68卷 186-191页

作者： hai Zou Yunfeng Bao Xueshang Xin Yu Qi Tengfeng Xie Fuxiang zhang State Key Laboratory of Catalysis Dalian National Laboratory for Clean Energy Dalian Institute of Chemical Physics Chinese Academy of Sciences School of Chemistry and Chemical Engineering Liaoning Normal University College of Chemistry Jilin University

Constructing type II heterostructures represents a widely recognized strategy for enhancing charge separation and photocatalytic efficiency,but it remains challenging to fabricate homologous heterostructures based on visible-light-responsive semiconductors,especially for popularly investigated （oxy）nitrides with low thermal ***,we synthesized a homologous heterostructure （denoted as YTON＿H） based on the oxynitrides of YTaO4-xNyand YTa *** heterostructure exhibits type II band structure alignment and intimate interface achieved through a magnesium （Mg） powder-assisted nitridation *** with widely reported heterologous heterostructures,the as-obtained YTON＿H homologous heterostructure could similarly exhibit enhanced charge separation as well as photocatalytic water splitting performance with respect to its counterparts(YTaO4-xNyand YTaON2).Meanwhile,detailed structural characterizations and spectroscopy analysis have been made to confirm the formation of heterostructure and promotion of spatial charge separation.

关键词： charge separation heterostructure oxynitride photocatalysis visible light