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Journal of Energy Chemistry 2019年第8期28卷 138-143,I0006页

作者： Yuan Guo Guangchao Han Yuanping Yi Beijing National Laboratory for Molecular Sciences CAS Key Laboratory of Organic Solids CAS Research/Education Center for Excellence in Molecular Sciences Institute of Chemistry Chinese Academy of SciencesBeijing 100190 China University of Chinese Academy Sciences Beijing 100049 China

Side chains play a critical role in tuning intermolecular interaction and charge transport in organic semiconductors. Here, we have systematically investigated the impact of branching positions of the alkyl side chains on the molecular packing and electron transport properties of a series of bay-linked dimeric perylenediimide(PDI) derivatives by atomistic molecular dynamics simulations in combination with charge transfer rate theory and kinetic Monte Carlo simulations. The results show that despite of different branching positions of the alkyl chains,π–π stacking is effectively inhibited for all the dimeric PDI derivatives. As the branching position moves away from the PDI backbone, the appearance of the alkyl atoms around the PDI backbone will first decrease and then increase. Correspondingly, the short contacts between the PDI moieties are first enhanced and then reduced. In particular, when the branching position is at the third carbon atom, the intermolecular connectivity becomes the most effective and the electron mobility is significantly increased by 2 times.

关键词： Molecular packing Electron mobility branching position Perylenediimide

Altering alkyl-chains branching positions for boosting the performance of small-molecule acceptors for highly efficient nonfullerene organic solar cells

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Science China Chemistry 2020年第3期63卷 361-369页

作者： Zhenghui Luo Rui Sun Cheng Zhong Tao Liu Guangye Zhang Yang Zou Xuechen Jiao Jie Min Chuluo Yang Shenzhen Key Laboratory of Polymer Science and Technology College of Materials Science and EngineeringShenzhen UniversityShenzhen 518060China Hubei Key Lab on Organic and Polymeric Optoelectronic Materials Department of ChemistryWuhan UniversityWuhan 430072China The Institute for Advanced Studies Wuhan UniversityWuhan 430072China eFlexPV Limited(China) ShenzhenChina Department of Materials Science and Engineering Monash UniversityVictoriaAustralia

The emergence of the latest generation of small-molecule acceptor(SMA)materials,with Y6 as a typical example,accounts for the surge in device performance for organic solar cells(OSCs).This study proposes two new acceptors named Y6-C2 and Y6-C3,from judicious alteration of alkyl-chains branching positions away from the Y6 *** to the Y6,the Y6-C2 exhibits similar optical and electrochemical properties,but better molecular packing and enhanced *** contrast,the Y6-C3 shows a significant blue-shift absorption in the solid state relative to the Y6 and *** as-cast PM6:Y6-C2-based OSC yields a higher power conversion efficiency(PCE)of 15.89%than those based on the Y6(15.24%)and Y6-C3(13.76%),representing the highest known value for as-cast nonfullerene ***,the Y6-C2 displays a good compatibility with the ***,a ternary OSC device based on PM6:Y6-C2:PC71BM(1.0:1.0:0.2)was produced,and it exhibits an outstanding PCE of 17.06%and an impressive fill factor(FF)of *** results improve understanding of the structureproperty relationship for state-of-the-art SMAs and demonstrate that modulating the structure of SMAs via fine-tuning of alkylchains branching positions is an effective method to enhance their performance.

关键词： alkyl-chain branching position small molecular acceptor organic solar cell power conversion efficiency fill factor

branching patterns of the left portal vein and consequent implications in liver surgery:The left anterior sector

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Hepatobiliary & Pancreatic Diseases International 2022年第4期21卷 399-402页

作者： Mattia Garancini Mauro Alessandro Scotti Luca Gianotti Antonio Rovere Fabio Uggeri Marco Braga Fabrizio Romano Unit of Hepatobiliary Pancreatic Surgery Department of General Surgery 1ASST-MonzaSan Gerardo HospitalMilano-Bicocca Universityvia Pergolesi 3320900 MonzaMBItaly Unit of Interventional Radiology Department of RadiologyASST-MonzaSan Gerardo HospitalMilano-Bicocca Universityvia Pergolesi 3320900 MonzaMBItaly

To the Editor: There are still some open issues about the systematization of the knowledge of the branching of the left portal vein(LPV) and the division in anatomo-functional units within the left liver. The first controversial topic concerns the division of S4 in subsegments. The Brisbane 20 0 0 system of Nomenclature of Hepatic Anatomy and Resections(B20 0 0) [1] does not mention such subdivision, but in literature this is still a matter of discussion.

关键词： branching portal discussion

MOMENTS OF CONTINUOUS-STATE branching PROCESSES IN LéVY RANDOM ENVIRONMENTS

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Acta Mathematica Scientia 2019年第3期39卷 781-796页

作者： Lina JI Xiangqi ZHENG School of Mathematical Sciences Beijing Normal University

For continuous-state branching processes in Lévy random environments, the recursion of n-moments and the equivalent condition for the existence of general f-moments are established, where f is a positive continuous f... 详细信息

关键词： branching processes continuous-state moments random environment stochastic equations

L log L criterion for a class of multitype superdiffusions with non-local branching mechanisms

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Science China Mathematics 2019年第8期62卷 1439-1462页

作者： Zhen-Qing Chen Yan-Xia Ren Renming Song Department of Mathematics University of Washington Seattle WA 98195 USA LMAM School of Mathematical Sciences & Center for Statistical SciencePeking University Beijing 100871 China Department of Mathematics University of Illinois Urbana IL 61801 USA

In this paper, we provide a pathwise spine decomposition for multitype superdiffusions with nonlocal branching mechanisms under a martingale change of measure. As an application of this decomposition,we obtain a necessary and sufficient condition(called the L log L criterion) for the limit of the fundamental martingale to be non-degenerate. This result complements the related results obtained in Kyprianou et al.(2012),Kyprianou and Murillo-Salas(2013) and Liu et al.(2009) for superprocesses with purely local branching mechanisms and in Kyprianou and Palau(2018) for super Markov chains.

关键词： multitype superdiffusion non-local branching mechanism switched diffusion spine decomposition martingale

Using 2D NMR to determine the degree of branching of complicated hyperbranched polymers

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Science China Chemistry 2008年第11期51卷 1057-1065页

作者： ZHU XinYuan CHEN Liang CHEN Yan YAN DeYue School of Chemistry and Chemical Engineering State Key Laboratory of Metal Matrix CompositesShanghai Jiao Tong UniversityShanghai 200240China Instrumental Analysis Center Shanghai Jiao Tong UniversityShanghai 200240China

Degree of branching (DB) is a crucial structure parameter of hyperbranched polymers, which can be determined by 1H NMR, quantitative 13C NMR, degradative method, etc. However, for complicated hy-perbranched polymers, intricate structure and severe overlap of spectral signals hinder the determina-tion of DB using traditional methods. In this work, the architecture of complicated hyperbranched polymers has been elucidated with the help of 2D NMR techniques. Using such a method, overlapped NMR signals can be well separated into a two-dimensional space, and additional structural information is also available. Correspondingly, quantitative analysis for complicated systems can be realized. De-termination of DBs for three types of complicated hyperbranched polymers synthesized from step-polymerization, self-condensation vinyl polymerization and self-condensation ring-opening po-lymerization is shown as examples.

关键词： hyperbranched polymer degree of branching 2D NMR

Electron branching Ratios Following Autoionization of the Ba 6pns States

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Chinese Physics Letters 2001年第4期18卷 516-518页

作者： LV Jun DAI Chang-Jian XU Yun-Fei LI Shi-Ben Department of Physics Zhejiang UniversityHangzhou 310027

The excitation spectra and branching ratios of ejected electrons of the Ba 6pns(J=1)autoionizing states are measured using multistep laser excitation scheme and time-of-flight electron *** energy dependence of branching ratios of Ba+6s state on energy is determined for the low-lying 6p1/2,3/2ns states,and compared with a previous R-matrix calculation.

关键词： spectroscopy. calculation. branching

ASYMPTOTIC PROPERTIES OF A branching RANDOM WALK WITH A RANDOM ENVIRONMENT IN TIME

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Acta Mathematica Scientia 2019年第5期39卷 1345-1362页

作者： Yuejiao WANG Zaiming LIU Quansheng LIU Yingqiu LI College of Mathematics and Computational Science Hunan First Normal University Changsha 410205 China School of Mathematics and Statistics Central South University Changsha 410083 China LMBA UMR CNRS 6205 Université de Bretagne-Sud F-56000 Vannes France School of Mathematics and Statistics Changsha University of Science and Technology Changsha 410004 China

We consider a branching random walk in an independent and identically distributed random environment ξ=(ξn) indexed by the time. Let W be the limit of the martingale Wn=∫e^-txZn(dx)/Eξ∫e^-txZn(dx), with Zn denoting the counting measure of particles of generation n, and Eξ the conditional expectation given the environment ξ. We find necessary and sufficient conditions for the existence of quenched moments and weighted moments of W, when W is non-degenerate.

关键词： branching random walk random environment quenched moments weighted moments

Production of very-high-amylose cassava by post-transcriptional silencing of branching enzyme genes

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Journal of Integrative Plant Biology 2020年第6期62卷 832-846页

作者： Wenzhi Zhou Shanshan Zhao Shutao He Qiuxiang Ma Xinlu Lu Xiaomeng Hao Hongxia Wang Jun Yang Peng Zhang National Key Laboratory of Plant Molecular Genetics CAS Center for Excellence in Molecular Plant SciencesInstitute of Plant Physiology and EcologyShanghai Institutes for Biological Sciencesthe Chinese Academy of SciencesShanghai 200032China Shanghai Key Laboratory of Plant Functional Genomics and Resources Shanghai Chenshan Plant Science Research CenterShanghai Chenshan Botanical Gardenthe Chinese Academy of SciencesShanghai 201602China University of Chinese Academy of Sciences Beijing 100049China

High amylose starch can be produced by plants deficient in the function of branching enzymes(BEs).Here we report the production of transgenic cassava(Manihot esculenta Crantz)with starches containing up to 50%amylose due to the constitutive expression of hair-pin ds RNAs targeting the BE1 or BE2 *** BE1-RNAi plant lines(BE1i)and BE2-RNAi plant lines(BE2i)were grown up in the field,but with reduced total biomass *** high amylose content in the storage roots of BE2i plant lines was *** starch granules of BE1i and BE2i plants had similar morphology as wild type(WT),however,the size of BE1i starch granules were bigger than that of *** of amylograms and thermograms of all three sources of storage starches revealed dramatic changes to the pasting properties and a higher melting temperature for BE2i *** chain length distribution analysis showed a slight increase in chains of DP>36 in BE1i lines and a dramatic increase in glucan chains between DP 10-20 and DP>40 in BE2i ***,BE2i starches displayed a B-type X-ray diffraction pattern instead of the A-type pattern found in BE1i and WT ***,cassava BE1 and BE2 function differently in storage root starch biosynthesis.

关键词： chains branching pattern

Cotton GhBRC1 regulates branching,flowering,and growth by integrating multiple hormone pathways

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The Crop Journal 2022年第1期10卷 75-87页

作者： Quan Sun Yuanhui Xie Huimin Li Jinlei Liu Rui Geng Ping Wang Zongyan Chu Ying Chang Guanjun Li Xiao Zhang Youlu Yuan Yingfan Cai State Key Laboratory of Cotton Biology Henan Key Laboratory of Plant Stress BiologySchool of Life SciencesHenan UniversityKaifeng 475000HenanChina Chongqing Key Laboratory of Big Data for Bio Intelligence College of BioinformationChongqing University of Posts and TelecommunicationsChongqing 400065China State Key Laboratory of Cotton Biology Key Laboratory of Cotton Genetic ImprovementMinistry of AgricultureInstitute of Cotton ResearchChinese Academy of Agricultural SciencesAnyang 455000HenanChina Kaifeng Academy of Agriculture and Forestry Kaifeng 475000HenanChina

Cotton architecture is partly determined by shoot branching and flowering *** BRC1 was previously identified by RNA-seq analysis of nulliplex-branching and normal-branching ***,the roles of Gh BRC1 in cotton remain *** the present study,investigations of nuclear localization and transcriptional activity indicated that Gh BRC1 has characteristics typical of transcription *** expression analysis showed that Gh BRC1 was highly expressed in axillary buds but displayed different expression patterns between the two branching *** of Gh BRC1 in Arabidopsis significantly inhibited the number of branches and promoted *** contrast,silencing Gh BRC1 in cotton significantly promoted seedling *** BRC1 was induced by multiple hormones,including strigolactones,which promoted seedling growth and seed germination of Arabidopsis plants overexpressing Gh *** with these findings,RNA-seq analysis of virus-induced gene silencing treated cotton revealed that a large number of genes were differentially expressed between Gh BRC1-silenced and control plants,and these genes were significantly enriched in plant hormone signalling ***,our data indicates that Gh BRC1 regulates plant branching and flowering through multiple regulatory pathways,especially those regulating plant hormones,with functions partly differing from those of Arabidopsis *** results provide insights into the molecular mechanisms controlling plant architecture,which is important for breeding cotton with ideal plant architecture and high yield.

关键词： Cotton GhBRC1 branching Flowering Growth