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Synthesis and Photovoltaic Properties of Polythiophene Incorporating with 3,4-Difluorothiophene Units

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Chinese Journal of Chemistry 2013年第11期31卷 1385-1390页

作者： Linquan Huang Dong yang Qiang Gao yan Liu Shengmei Lu jian Zhang Can Li State Key Laboratory of Catalysis Dalian Institute of Chemical Physics Chinese Academy of Sciences Dalian National Laboratory for Clean Energy Dalian Liaoning 116023 China Graduate University of Chinese Academy of Sciences Beijing 100049 China

Two polythiophene derivatives using fluorine atoms and hexyl or hexyloxy group as electron-withdrawing and donating substituents have been synthesized. The introduction of fluorine atoms to the polythiophene backbones simultaneously lowers the HOMO and narrows the bandgap, and the stronger electron-donating ability of hexyloxy side chain further reduces the bandgap. As a result, poly[3-hexylthiophene-2,5-diyl-alt-3,4-difluorothiophene] （PHTDFT） shows HOMO and bandgap of -5.31/1.83 eV and poly[3,4-dihexyloxythiophene-2,5-diyl-alt-3,4-di- fluorothiophene] （PDHOTDFT） shows HOMO and bandgap of -5.14/1.68 eV, both are lower than --4.76/2.02 eV of P3HT. Benefiting from the lower HOMO, PHTDFT：PC61BM （1 ＂ 1） polymer solar cells obtain a power conversion efficiency of 1.11% and an impressed open-circuit voltage of 0.79 V under solar illumination AM1.5 （100 mW/cm2）.

关键词： polythiophene derivatives 3,4-difluorothiophene polymer solar cell open-circuit voltage

Altitudinal changes of surface pollen and vegetation on the north slope of the Middle Tianshan Mountains,China

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Journal of Arid Land 2016年第5期8卷 799-810页

作者： yanG Zhenjing ZHANG Yun REN Haibao yan Shun KONG Zhaochen MA Keping NI jian Institute of Hydrogeology and Environmental Geology Chinese Academy of Geological Sciences State Key Laboratory of Vegetation and Environmental Change Institute of BotanyChinese Academy of Sciences Xinjiang Institute of Ecology and Geography Chinese Academy of Sciences State Key Laboratory of Environmental Geochemistry Institute of GeochemistryChinese Academy of Sciences

To provide information on vegetation patterns and altitudinal distributions of pollen assemblage in surface soil layers,their complicated relationships in a dryland mountain-basin system in northwestern China and a realistic basis for paleovegetational reconstruction,we investigated 86 vegetation quadrats and analyzed 80 soil samples from the surface soil layers along an altitudinal transect on the north slope of the Middle Tianshan Mountains from alpine cushion vegetation at 3,510 m near glacier to desert vegetation at 460 m in the Gurbantunggut *** to surface pollen assemblages and the results of the detrended correspondence analysis,the transect can be divided into six major altitudinal pollen zones as alpine cushion vegetation,alpine and subalpine meadows,montane Picea forest,forest-steppe ecotone,Artemisia desert and typical desert,which basically reflect the characteristics of the mountainous vegetation patterns on the north slope of the Middle Tianshan ***,Picea pollen also exists outside the spruce forest,Chenopodiaceae and Artemisia pollen appeared above the elevation of 1,300 m,indicating that most of them might be introduced from lower elevations by upslope *** pollen researches from three regions at different elevations further suggest that a high-frequency northwest anabatic wind has a remarkable influence on the transportation and dispersion of surface pollen in the area.

关键词： altitudinal transect vegetation zone pollen assemblage Picea forest the Middle Tianshan Mountains

Identification of Variable-Number Tandem-Repeat(VNTR)Sequences in Acinetobacter pittii and Development of an Optimized Multiple-Locus VNTR Analysis Typing Scheme

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Biomedical and Environmental Sciences 2015年第12期28卷 855-863页

作者： HU Yuan LI Bo Qing JIN Da Zhi HE Li Hua TAO Xiao Xia ZHANG jian zhong State Key Laboratory of Infectious Disease Prevention and Control Collaborative Innovation Center for Diagnosis and Treatment of Infectious DiseasesNational Institute for Communicable Disease Control and PreventionChinese Center for Disease Control and Prevention Binzhou Medical College Zhejiang Provincial Center for Disease Control and Prevention

Objective To develop a multiple-locus variable-number tandem-repeat(VNTR)analysis(MLVA)assay for Acinetobacter pittii *** Polymorphic VNTRs were searched by Tandem Repeats *** distribution and polymorphism of each VNTR locus were analyzed in all the *** genomes deposited in the NCBI genome database by BLAST and were evaluated with a collection of 20 well-characterized clinical *** strains and one reference *** MLVA assay was compared with pulsed-field gel electrophoresis(PFGE)for discriminating *** *** Ten VNTR loci were identified upon bioinformatic screening of *** genomes,but only five of them showed full amplifiability and good ***,an MLVA assay composed of five VNTR loci was *** typeability,reproducibility,stability,discriminatory power,and epidemiological concordance were *** with PFGE,the new optimized MLVA typing scheme provided the same and even greater *** Compared with PFGE,MLVA typing is a faster and more standardized alternative for studying the genetic relatedness of *** isolates in disease surveillance and outbreak investigation.

关键词： A.pittii MLVA typing VNTR

Application of an acrylic vessel supported by a stainless-steel truss for the JUNO central detector

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Science China(Technological Sciences) 2014年第12期57卷 2523-2529页

作者： WANG Yuan Qing ZONG Liang HENG Yue Kun WANG Zong Yi ZHOU yan HOU Shao Jing QIN zhong Hua MA Xiao yan Key Laboratory of Civil Engineering Safety and Durability of China Education Ministry Department of Civil EngineeringTsinghua University Central Detector Group Institute of High Energy Physics (IHEP) School of Civil and Architectural Engineering Wuhan University Key Laboratory of New Technology for Construction of Cities in Mountain Area Department of Civil EngineeringChongqing University

After the success of the Daya Bay experiment, the jiangmen Underground Neutrino Observatory （JUNO） was launched to measure neutrino-mass hierarchy and oscillation parameters and to study other neutrino physics. Its central detector is set for antineutrinos from reactors, the Earth, the atmosphere, and the Sun. The main requirements of the central detector are con- tainment of 20 kt of liquid scintillator, as the target mass, and 3% energy resolution. It is about a ball-shape detector of 38.5 m with -75% coverage of PMT on its inner surface. The design of such a huge detector is a big challenge because it must meet the requirements for several different types of physics measurement and possess the feasibility and reliability in its structure and engineering, all at reasonable time and cost. One option for the JUNO central detector is a hyper-scale acrylic ball sub- merged in the water to shield the background. This paper proposes a structural scheme for such an acrylic ball that is supported by a stainless-steel truss, inspired by point-supported glass-curtain walls in civil engineering. The preliminary design of the scheme is completed and verified by finite element （FE） method using ABAQUS. FE analysis shows that the scheme can con- trol the stress level of the acrylic ball within the limit of 5 to 10 MPa, in accordance with the demand of the design objective of the central detector. The scheme is of outstanding global stability and allows various chocces on local connections. We prove that the scheme is of good feasibility and should be a reasonable option for the central detector.

关键词： neutrino central detector acrylic stainless-steel truss point-supported glass-curtain wall

Involvement of a Putative Bipartite Transit Peptide in Targeting Rice Pheophorbide a Oxygenase into Chloroplasts for Chlorophyll Degradation during Leaf Senescence

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Journal of Genetics and Genomics 2016年第3期43卷 145-154页

作者： Qingjun Xie yan Liang jian Zhang Huakun Zheng Guojun Dong Qian Qian jianru Zuo State Key Laboratory of Plant Genomics and National Plant Gene Research Center Institute of Genetics and Developmental Biology Chinese Academy of Sciences Beijing 100101 China The University of Chinese Academy of Sciences Beijing 100049 China State Key Laboratory for Conservation and Utilization of Subtropical Agro-Bioresources South China Agricultural University Guangzhou 510642 China State Key Laboratory of Rice Biology China National Rice Research Institute Chinese Academy of Agricultural Sciences Hangzhou 310006 China Institute of Biotechnology Zhejiang University Hangzhou 310058 China

Leaf senescence is one of the major factors contributing to the productivity and the grain quality in crops. The regulatory mechanism of leaf senescence remains largely unknown. Here, we report the identification and characterization of a rice e_aarly senescence 1 （easl） mutant, which displayed an early leaf senescence phenotype, accompanying by dwarfism and reduced tiller number, eventually leading to the reduction of grain yield. Map-based cloning revealed that the nuclear gene EAS1 encodes a pheophorbide a oxygenase （PaO）, a key enzyme for chlorophyll breakdown. A highly conserved Thr residue of PaO was mutated into Ile in the easl mutant. Phylogenetic analysis indicates that PaO is an evolutionarily conserved protein, and EAS1 is 68% identical to the Arabidopsis ACCERLERATED CELL DEATH （ACD1） protein. Unlike ACD1 that contains a single transit peptide, EAS1 contains two putative transit peptides at its N-ter- minus, which are essential for its functionality, suggesting that targeting of EAS1 to the chloroplast is likely mediated by a putative bipartite transit peptide. Consistently, only a short version of EAS1 lacking the first putative transit peptide, but not the full-length EAS1, was capable of rescuing the Arabidopsis acdl mutant phenotype. These results suggest that rice EASI represents a functional PaO, which is involved in chlorophyl/degradation and may utilize a unique mechanism for its import into the chloroplast.

关键词： Pheophorbide a oxygenase Targeting Transit peptide Leaf senescence Rice

2001~2020年中国植被NPP对气象干旱的响应特征

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水电能源科学 2024年第8期42卷 17-21页

作者：郝岩张舰李保琦赵勇翟家齐高思颖王庆明石家庄铁道大学土木工程学院河北石家庄050043 德州市水利局山东德州253000 中国水利水电科学研究院流域水循环模拟与调控国家重点实验室北京100038

准确评估中国不同气候区植被净初级生产力(NPP)对气象干旱的响应特征,对于研究区域生态系统碳循环及气候变化有着重要意义。基于2001~2020年的NPP数据和构建的高分辨率标准化降水蒸散指数(SPEI)数据,采用Theil-Sen斜率估计、Mann-Kendal... 详细信息

准确评估中国不同气候区植被净初级生产力(NPP)对气象干旱的响应特征,对于研究区域生态系统碳循环及气候变化有着重要意义。基于2001~2020年的NPP数据和构建的高分辨率标准化降水蒸散指数(SPEI)数据,采用Theil-Sen斜率估计、Mann-Kendall趋势检验和Pearson相关分析等方法解析全国不同气候区NPP和SPEI的时空变化趋势,探索各气候区NPP对不同尺度气象干旱的响应特征。结果表明,各气候区NPP对气象干旱的响应表现出明显的空间异质性,北方半干旱区和北方半湿润区大部分区域NPP与SPEI-12呈显著正相关,而西南半湿润区多呈显著负相关,同时北方半干旱区NPP与夏季SPEI-3的相关性相较于与SPEI-12的相关性更为显著;各气候区NPP均与中长期SPEI和年中月份的短期SPEI表现出较高的相关性,但因区域气候条件不同,植被对短期干旱和长期干旱的响应特征均有差异。

关键词：植被 NPP SPEI 时空变化相关分析中国气候区

Dynamic Relationship Between Biologically Active Soil Organic Carbon and Aggregate Stability in Long-Term Organically Fertilized Soils

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Pedosphere 2012年第5期22卷 616-622页

作者： LI Cheng-Liang XU jiang-Bing HE Yuan-Qiu LIU yan-Li FAN jian-Bo College of Resources and Environment Shandong Agricultural UniversityTai'an 271018(China) Institute of Soil Science Chinese Academy of SciencesNanjing 210008(China) National Engineering Laboratory for Efficient Utilization of Soil and Fertilizer Resources Tai'an 271018(China)

Biologically active soil organic carbon （BASOC） is an important fraction of soil organic carbon （SOC）, but our understanding of the correlation between BASOC and soil aggregate stability is limited. At an ecological experimental station （28° 04＇-28° 37＇ N, 116° 41＇-117° 09＇ E） in Yujiang County, jiangxi Province, China, we analyzed the dynamic relationship between soil aggregate stability and BASOC content over time in the red soil （Udic Ferrosols） fertilized with a nitrogen-phosphorus-potassium chemical fertilizer （NPK） without manure or with NPK plus livestock manure or green manure. The dynamics of BASOC was evaluated using CO2 efflux, and soil aggregates were separated according to size using a wet-sieving technique. The soils fertilized with NPK plus livestock manure had a significantly higher content of BASOC and an improved aggregate stability compared to the soils fertilized with NPK plus green manure or NPK alone. The BASOC contents in all fertilized soils decreased over time. The contents of large aggregates （800-2 000 μm） dramatically decreased over the first 7 d of incubation, but the contents of small aggregates （〈 800 μm） either remained the same or increased, depending on the incubation time and specific aggregate sizes. The aggregate stability did not differ significantly at the beginning and end of incubation, but the lowest stability in all fertilized soils occurred in the middle of the incubation, which implied that the soils had a strong resilience for aggregate stability. The change in BASOC content was only correlated with aggregate stability during the first 27 d of incubation.

关键词： aggregate size CO2 release manure mean weight diameter organic fertilization

Measuring the spreadability of users in microblogs

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Journal of Zhejiang University-Science C(Computers and Electronics) 2013年第9期14卷 701-710页

作者： Zhao-yun DING yan JIA Bin ZHOU Yi HAN Li HE jian-feng ZHANG College of Information Systems and Management National University of Defense Technology School of Computer Science National University of Defense Technology

Message forwarding (e.g.,retweeting on ***) is one of the most popular functions in many existing microblogs,and a large number of users participate in the propagation of information,for any given *** this large number can generate notable diversity and not all users have the same ability to diffuse the messages,this also makes it challenging to find the true users with higher spreadability,those generally rated as interesting and authoritative to diffuse the *** this paper,a novel method called SpreadRank is proposed to measure the spreadability of users in microblogs,considering both the time interval of retweets and the location of users in information *** were conducted on a real dataset from Twitter containing about 0.26 million users and 10 million tweets,and the results showed that our method is consistently better than the PageRank method with the network of retweets and the method of retweetNum which measures the spreadability according to the number of ***,we find that a user with more tweets or followers does not always have stronger spreadability in microblogs.

关键词： Spreadability Influence PageRank Microblogs Social media Social network SpreadRank

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六环石改性杨木木材的制备

林产工业 2024年第5期61卷 24-27,69页

作者：崔文燕王明涛章宇麒罗执赢于建芳内蒙古农业大学材料科学与艺术设计学院内蒙古呼和浩特010018 内蒙古自治区沙生灌木资源纤维化和能源化开发利用重点实验室内蒙古呼和浩特010018

为提高木材利用率,改善人工速生林密度低、强度低、易皱缩变形等不足,本文以人工速生杨木为研究对象,以内蒙古自治区特有的矿物六环石为改性材料,采用真空加压浸渍改性技术将六环石注入木材中,并对改性材的性能进行测试与表征。结果表明... 详细信息

为提高木材利用率,改善人工速生林密度低、强度低、易皱缩变形等不足,本文以人工速生杨木为研究对象,以内蒙古自治区特有的矿物六环石为改性材料,采用真空加压浸渍改性技术将六环石注入木材中,并对改性材的性能进行测试与表征。结果表明:六环石改性杨木木材的最佳浸渍次数为8次,单次浸渍工艺为真空浸渍120 min,常压浸渍5 min,再进行绝干处理。改性后的木材其平均增重率及吸液率分别为15.33%和146.37%,较素材的气干密度和全干密度分别提高了23.25%和21.95%。研究结果为改性材的制备和利用提供了新思路。

关键词：浸渍改性六环石速生杨木改性材物理性能