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Diketopyrrolopyrrole-based Conjugated Polymers as Additives to Optimize Morphology for Polymer Solar Cells

Chinese Journal of Polymer Science 2016年第4期34卷 491-504页

作者： Xun-fan Liao Jing wang Shuang-ying chen 谌烈 yi-wang chen College of Chemistry/Institute of Polymers Nanchang University College of Chemical Engineering Jiangxi Normal University Jiangxi Provincial Key Laboratory of New Energy Chemistry Nanchang University

Novel random copolymers for optimizing the morphology of the active layer for high performance organic photovoltaic devices have been demonstrated. Three ternary random copolymers PTBDTDPPSiCN（3/7）, PTBDTDPPSiCN（5/5）, PTBDTDPPSiCN（7/3） were prepared by polymerization of electron-donating thienyl-substituted benzodithiophene （TBDT） with 2,5-bis[8-（1,1,3,3,5,5,5-heptamethyltrisiloxane-3-yl）octly]-pyrrolo[3,4-c]pyrrole-1,4-dione （DPPSi） and 2,5-dio[5-（5-cyano-5,5-dimethyl-pentyl）]-3,6-dithiophen-2-yl-pyrrolo[3,4-c]pyrrole-1,4-dione （DPPCN） of different ratios. The DPPCN block can well-tune the light absorption and molecular packing, while the DPPSi block is in favor of enhancing the charge mobility. And the formation of organic Si--O--Si networks is beneficial to stabilize the morphology of the active layer. These new copolymers have narrow bandgaps and broaden visible light absorption from 500 nm to 1000 nm. Careful balance of the contents of the trimethoxysilyl group and the cyano group can well-tune the surface energy and morphology of the copolymers. Incorporation of these novel copolymers as additives into the blend of poly（3-hexylthiophene）（P3HT） and [6,6]-phenyl-C60-butyric acid methyl ester （PC61BM） is found to effectively broaden the light absorption, improve the compatibility and morphology of the active layer. As a result, some devices with certain ratios of these copolymers as additives achieve the enhanced efficiency compared with the device based on pristine P3HT：PC61BM.

关键词： Ternary random copolymers Additive Morphology Polymer solar cells.

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Is playing-as-downloading feasible in an eMule P2P file sharing system?

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Journal of Zhejiang University-Science C(Computers and Electronics) 2010年第6期11卷 465-475页

作者： Wen-yi wang Yao-wu chen Advanced Digital Technology and lnstruments Institute Zhejiang University Hangzhou 310027 China

Peer-to-peer(P2P) swarm technologies have been shown to be very efficient for large scale content distribution systems, such as the well-known BitTorrent and eMule ***, these systems have been designed for generic file sharing with little consideration of media streaming support, and the user cannot start a movie playback before it is completely *** playing-as-downloading capability would be particularly useful for a downloading peer to evaluate if a movie is valuable to be downloaded, and it could also help the P2P content distribution system to locate and eliminate the polluted *** this paper we address this issue by introducing a new algorithm, wish driven chunk distribution(WDCD), which enables the P2P file sharing system to support the video-on-demand(VOD) function while keeping the P2P native downloading speed.A new parameter named next-play-frequency is added to the content chunk to strike a replication balance between downloading and streaming *** modify the eMule as the test bed by adding the WDCD algorithm and then verify the prototype implementation by *** experimental results show that the proposed algorithm can keep the high downloading throughput performance of the eMule system with a good playing-as-downloading function.

关键词： Peer-to-peer(P2P) Video-on-demand(VOD) Playing-as-downloading eMule

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Pyrrol-2-yl-methanone Modified Silica as Electron Acceptor for the Oxidation of Water Catalyzed by Cobalt（II） Complexes

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Chemical Research in Chinese Universities 2015年第5期31卷 797-800页

作者： WU yi wang Li chen Qiuyun School of Chemistry and Chemical Engineering Jiangsu University Zhenjiang 212013 P. R. China

To develop a new type of non-oxidant electron acceptors for water oxidation, 3-（methyl）phenyl-（3,5- dimethyl-1H-pyrrol-2-yl）methanone modified silica（SiO2@py） was synthesized and used as host to Co4O4 cubane forming nanoparticles（SiO2@pyCo4）. In the presence of Ru（bpy）3^2＋ and under the irradiation of white LED（light emitting diode） light（10 W）, SiO2@pyCo4 can catalyze water oxidation without extra electron acceptor（e.g., Na2S2O8） Moreover, the turnover frequency（TOF） value of SiO2@pyCo4 is larger than that of Co4O4 cubane under the same conditions, and the longer lasting time of SiO2@pyCo4 indicates that SiO2@py can enhance the stability of Co4O4 in water. Our results provide an economic route to develop dioxygen evolution systems based on the assembly of organic electron acceptor modified silica with active cobalt complexes.

关键词： Silica Water oxidation Electron acceptor

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Spatial patterns and driving forces of land change in Tibetan-inhabited Three Rivers Headwaters region, China

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Journal of Mountain Science 2019年第1期16卷 207-225页

作者： YU Yao GUO Zhou wang yi-chen Department of Geography National University of Singapore

The Three Rivers Headwaters Region(TRHR) plays a key role in regulating water supply and climate of East Asia. A comprehensive understanding of the processes and driving forces of the long-term land use dynamics of the TRHR is needed to guide sustainable land resource management and regional ecological conservation strategies. This study examined long-term land change patterns in the TRHR and investigated the driving forces of the change. First, Landsat TM/ETM+ images covering TRHR of four time points from 1987 to 2016 were used to derive land use patterns, and statistical metrics were applied to quantify the spatial and temporal changes. Second, Principal Component Analysis and correlation analysis were employed to analyze environmental and social-economic data to identify the driving forces of land use change. Third, potential influences of the religion of Tibetan Buddhism on land use change were explored using GIS analysis, questionnaire survey and field observation. Results showed that areas of barren land, agricultural land, and built-up land largely increased, while areas of grassland and forest greatly decreased, with the highest change rate occurring in the most recent decade of analysis(from 2007 to 2016). Among the three headwater regions, the Yellow River Headwater Region showed an overall higher changing speed than the other two headwater regions. The regional driving forces of change in TRHR includedsocial-economic development, climatic condition, pressure of population growth, and environmental protection activities. It was also found that Tibetan Buddhism can help slow down the changes caused by human activities.

关键词： Land use land cover Tibetan Plateau Tibetan Buddhism Religious environmental protection Grassland degradation

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Synthesis and Phase Behavior of Poly(1-alkyne) with Liquid Crystalline-induced Luminescence Enhancement

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Chemical Research in Chinese Universities 2010年第6期26卷 1035-1044页

作者： ZHOU Dan chen yi-wang chen Lie LI Fan NIE Hua-rong YAO Kai Institute of Polymers Department of Chemistry Nanchang University Nanchang 330031 P. R. China

Poly（1-alkyne） with octoxy spacer —{[HC=C（CH2）8O—terphenyl—CN]}n—（PA8CN） and terphenyl liquid crystalline pendant was synthesized,and the effects of structure on the optical properties,especially the liquid crystallinity behavior of the polymer and monomer were *** monomer was prepared in high yields（92.30%） by coupling and etherification reactions and successfully polymerized in the presence of Rh catalyst and Et3N cocatalyst in high yields with trans-rich（86.27%） stereoregular *** to the monomer showing mixed monolayer structure,its corresponding polymer PA8CN formed homogeneous monolayer *** photoexcitation,strong blue emission peak of PA8CN appeared at 413 nm[fluorescence quantum yield,ΦF = 68% when excited at 330 nm in tetrahydrofuran（THF） solution].Compared with its solid film photoexcitated at 330 nm at room temperature,the UV light-emitting band of PA8CN solid film from its liquid crystalline with liquid nitrogen quenched rapidly at 236 ℃ was red-shift 10 nm with higher intensity,which may be ascribed to the fact that the effectual conjugation and the order degree of the molecule in the liquid crystalline state of the polymer were enhanced,the energy loss caused by the thermal vibration was decreased,thus resulting in the observed hyperchromic effect.

关键词： Polyacetylene Liquid crystallinity Phase transition Photoluminescence

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Superficial angiomyxoma of penis： a case report of a 6-year follow-up

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Asian Journal of Andrology 2017年第2期19卷 262-263页

作者： yi-chen wang Xiao-Ming Li Gan-Ping Zhong Zhe Xing Zhi-Ping wang Department of Urology Gansu Nephro-Urological Clinical Center Key Laboratory of Diseases of the Urinary System Gansu Province Second Hospital Lanzhou University Lanzhou China Department of Pathology Second Hospital Lanzheu University Lanzhou 730030 China Department of Clinical Science University of Bergen Bergen 5021 Norway

Dear Editor, We report a case of an 18-year-old Chinese man with two recurring asymptomatic superficial angiomyxomas on his penis. After an incisional biopsy, we resected the masses on the proximal and distal ends of... 详细信息

关键词： Superficial angiomyxoma penis case report

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Atmospheric chemistry of 2-nitrobenzaldehyde:Initiated by photo-excitation,OH-oxidation,and small TiO_(2) clusters adsorption catalysis

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Journal of Environmental Sciences 2024年第5期139卷 123-137页

作者： Feng-Yang Bai Xiang-Huan Liu Ting-Ting Meng Zhou Yu yi-chen wang Shuang Ni Zhen Zhao Institute of Catalysis for Energy and Environment College of Chemistry and Chemical EngineeringShenyang Normal UniversityShenyang 110034China

The fate of 2-nitrobenzaldehyde(2-NBA)is of interest in atmospheric chemistry as it is a semi-volatile organic compound with high *** study presents a quantum chemical study of the gas-phase reactions of 2-NBA photo-excitation and OH-oxidation in the absence and presence of small TiO_(2) *** further understand the unknown photolysis mechanism,the photo-reaction pathways of ground singlet state and the lying excited triplet state of 2-NBA were investigated including the initial and subsequent reactions of proton transfer,direct CO,NO_(2),and HCO elimination routes in the presence of O_(2) and ***,the OH-mediated degradation of 2-NBA proceeded via five H-extraction and six OH-addition channels by indirect mechanism,which follows a succession of reaction steps initiated by the formation of weakly stable intermediate *** H-extraction from the-CHO group was the dominant pathway with a negative activation energy of-1.22 kcal/*** calculated rate coefficients at 200–600 K were close to the experimental data in literature within 308-352 K,and the kinetic negative temperature independence was found in both experimental literature and computational ***,2-NBA was favored to be captured onto small TiO_(2) clusters via six adsorption configurations formed via various combination of three types of bonds of Ti…O,Ti…C,and O…H between the molecularly adsorbed 2-NBA and TiO_(2) *** indicted that the chemisorptions of aldehyde oxygen have largest *** results suggested adsorption conformations have a respectable impact on the catalysis *** study is significant for understanding the atmospheric chemistry of 2-nitrobenzaldehyde.

关键词： 2-nitrobenzaldehyde OH radical oxidation Rate coefficient Photolysis mechanism Adsorption catalysis

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Effects of angiotensin II on connexin 43 of VSMCs in arteriosclerosis

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Journal of Zhejiang University-Science B(Biomedicine & Biotechnology) 2006年第8期7卷 648-653页

作者： CAI Wei RUAN Li-ming wang yi-na chen Jun-zhu Department of Internal Medicine the First Affiliated Hospital School of Medicine Zhejiang University Hangzhou 310003 China

Objective： To observe the effect ofangiotensin Ⅱ （Ang Ⅱ） on expression of gap junction channel protein connexin 43 （Cx43） in the proliferation process of vascular smooth muscle cells （VSMCs） during the early stage of arteriosclerosis. Methods： Thirty-two adult male rabbits were randomly divided into 4 groups. Rabbits in Group A were fed common diet while others in Groups B, C, and D were fed high-cholesterol diet. Losartan （10 mg/（kg.d）） and ramipril （0.5 mg/（kg-d）） were added in the diet of Groups C and D, respectively. The animals were sacrificed after 8 weeks and abdominal aortas were removed and dissected. The expression of Cx43 was assayed using RT-PCR and Western Blotting analysis. Results： Cx43 was increased markedly in both protein and mRNA level in Groups B, C, and D fed high-cholesterol diet compared with that in control group （P〈0.01）. Cx43 level in losartan or ramipril treated groups was higher than that in control group （P〈0.01, P〈0.05）, but lower than that in high-cholesterol diet groups （P〈0.05, P〈0.01）. Conclusion： Cx43 level was upregulated in VSMCs during early atherosclerosis. Losartan and ramipril can inhibit the expression of Cx43.

关键词： Atherosclerosis Connexin mRNA Losartan Ramipril

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Structural Design and Property Characterization of Bi-functional Photorefractive Polymer

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Chinese Chemical Letters 1999年第8期10卷 667-670页

作者： yi wang chen Yuan Kang HE Hui ying chen Feng wang Qi Huang GONG (College of Chemistry and Molecular Engineering, Peking University. Beijing 100871)(Physical Department. Peking University. Beijing 100871) Coll. of Chem. and Molec. Eng. Peking University Beijing 100871 China Physical Department Peking University Beijing 100871 China

A novel bi-functional photorefractive acrylate polymer with pendant carbazolyl groups and azo derivatives as side chains was synthesized. Photorefractive experiments showed a high two-beam coupling gain coefficient of... 详细信息

关键词： acrylate polymer bi-functional polymer photorefractive material

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Photorefractive Effect in Poly(N-vinylcarbazole)-Based Composite Sensitised by C_(60)

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Chinese Chemical Letters 1997年第9期8卷 807-810页

作者： Zhi Jie ZHANG yi wang chen Yuan Kang HE and Hui ying chen(Institute of Polymer Science, College of Chemistry, Peking University, Beijing, 100871)Zhi Jian chen Shu Feng wang and Qi Huang GONG(Department of Physics, Mesoscopic Physics Laboratory, Peking U Institute of Polymer Science College of Chemistry Peking University Beijing 100871 China Department of Physics Mesoscopic Physics Laboratory Peking University Beijing 100871 China

A new PVK-based photorefractive polymer composite sensitized by C60 and doped with a higher content of EO chromophore was prepared. The high optical quality thin-film was formed between two ITOcovered glass electrodes. Two-beam-coupling (2BC) experiment was performed by using a He-Ne laser (at wavelength 632.8nm), and an obvious photorefractive performance was observed. The dependence of two-beamcoupling gain coefficient on the applied poling dc electric field was measured.

关键词： Photorefractive Effect in Poly Based Composite Sensitised by C N-vinylcarbazole Rev

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