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Ethynyl-linked perylene bisimide based electron acceptors for non-fullerene organic solar cells

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Chinese Chemical Letters 2018年第2期29卷 325-327页

作者： Changshi yu yunhua xu Shijie Liang xudong Jiang Guitao Feng Cheng Li Weiwei Li Deportment of Chemistry School of Science Beijing Jiaotong University Beijing 100044 China Beijing National Laboratory for Molecular Sciences CAS Key Laboratory of Organic Solids Institute of Chemistry Chinese Academy of Sciences Beijing 100190 China

In this work, star-shaped perylene bisimide（PBI） derivatives with spiro-aromatic cores linked with ethynyl units were developed as electron acceptors for non-fullerene organic solar cells. The ethynyl linkers were found to enhance the planarity of the conjugated backbone, resulting in high electron mobilities and near-infrared absorption. The ethynyl-linked PBI acceptors showed high power conversion efficiencies（PCEs） up to 4.27% due to the high short-circuit current density（Jsc） of 8.52 mA/cm^2 and fill factor（FF） of 0.59, while the PBI acceptor without ethynyl units provided a low PCE of 3.57% in nonfullerene solar cells. The results demonstrate that ethynyl units can be applied into designing new PBI electron acceptors with improved charge transport properties and photovoltaic performance.

关键词： Electron acceptor Non-fullerene organic solar cells Perylene bisimide Charge transport Ethynyl

Mapping Domain- and Age-Specific Functional Brain Activity for Children’s Cognitive and Affective Development

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Neuroscience Bulletin 2021年第6期37卷 763-776页

作者： Lei hao Lei Li Menglu Chen Jiahua xu Min Jiang Yanpei Wang Linhua Jiang xu Chen Jiang Qiu Shuping Tan Jia-Hong Gao Yong He Sha Tao Qi Dong Shaozheng Qin State Key Laboratory of Cognitive Neuroscience and Learning&IDG/McGovern Institute for Brain Research Beijing Normal UniversityBeijing 100875China College of Teacher Education Southwest UniversityChongqing 400715China Key Laboratory of Beijing Key Laboratory of Brain Imaging and Connectomics Beijing Normal UniversityBeijing 100875China School of Information Engineering Huzhou UniversityHuzhou 313000China Key Laboratory of Cognition and Personality(SWU) Ministry of EducationChongqing 400715China Faculty of Psychology Southwest UniversityChongqing 400715China Beijing HuiLongGuan Hospital Peking UniversityBeijing 100096China Center for MRI Research Academy for Advanced Interdisciplinary StudiesPeking UniversityBeijing 100871China

The human brain undergoes rapid development during childhood,with significant improvement in a wide spectrum of cognitive and affective *** domain-and age-specific brain activity patterns has important implications for characterizing the development of children’s cognitive and affective *** current mainstay of brain templates is primarily derived from structural magnetic resonance imaging(MRI),and thus is not ideal for mapping children’s cognitive and affective brain *** integrating task-dependent functional MRI data from a large sample of 250 children(aged 7 to 12)across multiple domains and the latest easy-to-use and transparent preprocessing workflow,we here created a set of age-specific brain functional activity maps across four domains:attention,executive function,emotion,and risky ***,we developed a toolbox named Developmental Brain Functional Activity maps across multiple domains that enables researchers to visualize and download domain-and age-specific brain activity maps for various *** toolbox and maps have been released on the Neuroimaging Informatics Tools and Resources Clearinghouse website(http://***/projects/dbfa).Our study provides domain-and age-specific brain activity maps for future developmental neuroimaging studies in both healthy and clinical populations.

关键词： Brain activity maps FMRI Cognition Emotion Reward Development

Low Temperature Molten Salt Synthesis of Perovskite-type ACeO3（A=Sr, Ba） in Eutectic NaCl-KCl

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Chemical Research in Chinese Universities 2015年第3期31卷 342-346页

作者： LIU Ming HU Lei xu Pengfei Zhao Kun ZONG Lingbo yu Ranbo CHEN Jun Department of Physical Chemistry University of Science and Technology Beijing Beijing 100083 P.R.China

A molten salt method was developed for the synthesis of ACeO3（A=Sr, Ba） with perovskite structure at 750 ℃（SrCeO3） and 850 ℃（BaCeO3） in the eutectic NaCl-KCl. The synthetic temperature was much lower than that of the conventional method（generally〉1000 ℃）. The structure and morphology of the product were characterized by means of X-ray diffraction（XRD）, field emission scanning electron microscopy（FESEM） and transmission electron microscopy（TEM）. The results show that the synthesized octahedral SrCeO3 crystallizes in the orthorhombic system with the unit cell parameters of a=0.85855 nm, b=0.61523 nm, c=0.60059 nm, and the synthesized cuboid BaCeO3 crystallizes in the cubic system with the unit cell parameter of a=0.43962 nm. The result of X-ray photoelectron spectroscopy（XPS） analysis indicates that both Ce4＋ and Ce3＋ exist in the two structures, and the Ce4＋/Ce3＋ peak area ratios for SrCeO3 and BaCeO3 are 1.93 and 2.12, respectively. Meanwhile, the adsorbed/lattice oxygen ratios（1.87 for SrCeO3 and 3.04 for BaCeO3） indicate the existence of a lot of oxygen vacancies in the structures of SrCeO3 and BaCeO3, which indicates a far-reaching significance to study the corresponding physicochemistry performance.

关键词： Molten salt synthesis Perovskite SrCeO3 BaCeO3

Reductive Cleavage of C-O Bond in Model Compounds of Lignin

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Chinese Journal of Chemistry 2017年第6期35卷 938-942页

作者： Huanjun xu Xinwei Liu Yanfei Zhao Cailing Wu yu Chen Xiang Gao Zhimin Liu Beijing National Laboratory for Molecular Sciences CAS Key Laboratory of Colloid lnterjace and Chemical Thermodynamics Institute of Chemistry Chinese Academy of Sciences Beijing 100190 China

A simple protocol for reductive cleavage of C--O bond in diaryl and aryl methyl ethers was reported, in which Nail served as a reducing agent and KO Bu as a base and a radical initiator. The combination of Nail and KOBu displayed high efficiency for reductive cleavage of C-O bond in diaryl and awl ethers （e.g., dibenzofuran, diphe- nyl ether, anisole） without the hydrogenation of the aryl rings, in the absence of any other catalysts or ligands at 140 ℃, producing corresponding arenes and phenols. It was indicated that the reaction was under a radical mecha- nism.

关键词： lignin C-O bond aryl ethers reductive cleavage aromatics

Roles and mechanisms of exosomal non-coding RNAs in human health and diseases

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Signal Transduction and Targeted Therapy 2021年第12期6卷 3435-3465页

作者： Chen Li yu-Qing Ni Hui xu Qun-Yan Xiang Yan Zhao Jun-Kun Zhan Jie-yu He Shuang Li You-Shuo Liu Department of Geriatrics The Second Xiangya HospitalCentral South UniversityChangshaHunan 410011China Institute of Aging and Age-related Disease Research Central South UniversityChangshaHunan 410011China

Exosomes play a role as mediators of cell-to-cell communication,thus exhibiting pleiotropic activities to homeostasis *** non-coding RNAs(ncRNAs),mainly microRNAs(miRNAs),long non-coding RNAs(lncRNAs),and circular RNAs(circRNAs),are closely related to a variety of biological and functional aspects of human *** the exosomal ncRNAs undergo tissuespecific changes due to diverse internal or external disorders,they can cause tissue dysfunction,aging,and *** this review,we comprehensively discuss the underlying regulatory mechanisms of exosomes in human *** addition,we explore the current knowledge on the roles of exosomal miRNAs,lncRNAs,and circRNAs in human health and diseases,including cancers,metabolic diseases,neurodegenerative diseases,cardiovascular diseases,autoimmune diseases,and infectious diseases,to determine their potential implication in biomarker identification and therapeutic exploration.

关键词： diseases somal homeostasis

Ductular proliferation in liver tissues with severe chronic hepatitis B: An immunohistochemical study

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World Journal of Gastroenterology 2006年第9期12卷 1443-1446页

作者： Yao-Kai Chen xu-Xia Zhao Jun-Gang Li Song Lang yu-Ming Wang Institute of Infectious Diseases Southwest Hospital Third Military Medical University Chongqing 400038 China Department of Hepatology Gucheng People's Hospital Gucheng 443003 Hubei Province China

AIM： To clarify the pathogenesis of ductular proliferation and its possible association with oval cell activation and hepatocyte regeneration. METHODS： Immunohistochemical staining and image analysis of the ductular structures in the liver tissues from 11 patients with severe chronic hepatitis B and 2 healthy individuals were performed. The liver specimens were sectioned serially, and then cytokeratin 8 （CK8）, CK19, OV6, proliferating cell nuclear antigens （PCNA）, glutathione-S-transferase （GST）, α-fetal protein （AFP） and albumin were stained immunohistochemically. RESULTS： Typical and atypical types of ductular proliferation were observed in the portal tracts of the liver tissues in all 11 patients. The proliferating ductular cells were positive for CKS, CK19, OV6 and PCNA staining. Some atypical ductular cells displayed the morphological and immunohistochemical characteristics of hepatic oval cells. Some small hepatocyte-like cells were between hepatic oval cells and mature hepatocytes morphometrically and immunohistochemically. CONCLUSION： The proliferating ductules in the liver of patients with severe chronic liver disease may have different origins. Some atypical ductular cells are actually activated hepatic oval cells. Atypical ductular proliferation is related to hepatocyte regeneration and small hepatocyte-like cells may be intermediate transient cells between hepatic oval cells and mature hepatocytes.

关键词： Ductular proliferation Chronic hepatitis B Hepatocyte regeneration

Effects of acid deposition on the avoidance behavior of Folsomia candida (Collembola, Isotomidae)

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Soil Ecology Letters 2022年第2期4卷 164-170页

作者： Xiaofeng Luo Linglong Zhu Guoliang xu Jiaen Zhang Jianlong xu Shiqin yu Xiaohua Chen School of Geographical Science and Remote Sensing Guangzhou UniversityGuangzhou 510006China Guangdong Province Rural Water Environment Non-point Source Pollution Comprehensive Treatment Engineering Technology Research Center Guangzhou 510006China Guangdong Provincial Key Laboratory of Eco-circular Agriculture South China Agricultural UniversityGuangzhou 510642China

Excessive acid deposition causes soil acidification,and changes the soil microhabitat,thus affecting the survival and reproduction of soil *** candida(Collembola,Isotomidae),as a model organism,is widely used to assess the chemical toxicity in soil,and its avoidance response can indicate the environmental *** this study,we used Folsomia candida to assess the risks of acid deposition on soil *** pH(3.0,3.5,4.0,4.5,5.0,and 5.5)treatments were set up in petri dish experiments,and the avoidance behavior of Folsomia candida was measured after 12,24,and 48 h exposure to the pH *** results indicated that(1)both the exposure duration and pH level influenced avoidance behavior of collembolan.(2)After 12 h exposure,most of the individuals showed avoidance behavior but without significant differences among the treatments.(3)After 24 h exposure,significant avoidance behavior was observed at pH 3.0,3.5,and 4.0.(4)After 48 h exposure,avoidance behavior was found in all treatment conditions except for pH *** study clarified the direct responses of soil fauna to acid deposition,and indicated that both pH and length of exposure influenced the avoidance behavior of Folsomia *** the experimental period,the collembolan reacted negatively and showed consistent avoidance behavior at pH 3.0,3.5,and *** avoidance behavior was apparent between pH 4.5 and 5.0 and not observed at pH 5.5,indicating that the latter was the preferred pH environment.

关键词： Collembolan Acid rain Behavioral avoidance

Mapping Daily Temperature and Precipitation in the Qilian Mountains of Northwest China

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Journal of Mountain Science 2014年第4期11卷 896-905页

作者： PENG Shou-zhang Zhao Chuan-yan WANG Xiao-ping xu Zhong-lin LIU Xing-ming hao Hu YANG Shi-fei State Key Laboratory of Pastoral Agricultural Ecosystem Institute of Arid Agroecology School of Life Sciences Lanzhou University Institute of Arid Meteorology China Meteorological Administration MOE Key Laboratory of Oasis Ecology College of Resource and Environmental Science Xinjiang University Management Bureau of Qilian Mountains National Nature Reserve in Gansu

Daily meteorological data are the critical inputs for distributed hydrological and ecological models. This study modified mountain microclimate simulation model （MTCLIM） with the data from 19 weather stations, and compared and validated two methods （the MTCLIM and the modified MTCLIM） in the Qilian Mountains of Northwest China to estimate daily temperature （i.e., maximum temperature, minimum temperature） and precipitation at six weather stations from i January 2000 to 31December 2009. The algorithm of temperature in modified MTCLIM was improved by constructing the daily linear regression relationship between temperature and elevation, aspect and location information. There are two steps to modify the MTCLIM to predict daily precipitation： firstly, the linear regression relationship was built between annual average precipitation and elevation, location, and vegetation index; secondly, the distance weight for measuring the contribution of each weather station on target point was improved by average wind direction during the rainy season. Several regression analysis and goodness-of-fit indices （i.e., Pearson＇s correlation coefficient, coefficient of determination, mean absolute error, root-mean-square error and modelingefficiency） were used to validate these estimated values. The result showed that the modified MTCLIM had a better performance than the MTCLIM. Therefore, the modified MTCLIM was used to map daily meteorological data in the study area from 2000 to 2009. These results were validated using weather stations with short time data and the predicted accuracy was acceptable. The meteorological data mapped could become inputs for distributed hydrological and ecological models applied in the Qilian Mountains.

关键词： MTCLIM (Mountain microclimatesimulation model) Wind direction Precipitation Temperature Qilian Mountains.

氯化胆碱-乙二醇-水媒介制备M型钡铁氧体及其相对结晶纯度研究

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沈阳理工大学学报 2025年第1期44卷 51-58页

作者：于巧吉任本景孙钰琦许清馨王晓仪于爽孟锦宏沈阳理工大学环境与化学工程学院沈阳110159

采用氯化胆碱-乙二醇(CC-EG)部分取代水溶剂,以相对结晶纯度(RCP)为实验指标,依据7因素12水平均匀设计方案,经化学共沉淀方法制备得到高结晶度、高纯度的M型钡铁氧体(BaFe_(12)O_(19))。通过对制备样品的XRD谱进行分峰拟合,计算各样品的... 详细信息

采用氯化胆碱-乙二醇(CC-EG)部分取代水溶剂,以相对结晶纯度(RCP)为实验指标,依据7因素12水平均匀设计方案,经化学共沉淀方法制备得到高结晶度、高纯度的M型钡铁氧体(BaFe_(12)O_(19))。通过对制备样品的XRD谱进行分峰拟合,计算各样品的RCP;经二次多项式逐步回归分析,建立RCP与主要合成因素(Fe/Ba摩尔比、CC-EG含量、pH、静置时间、预烧温度、焙烧温度、焙烧时间)间的回归模型;依据回归分析结果,探究模型中各项、各因素及因素间相互作用对RCP影响的主次顺序,揭示了将CC-EG引入BaFe_(12)O_(19)合成过程以提高其RCP的可行性。最优水平组合分析及验证实验结果进一步表明:以CC-EG部分取代水溶剂可提高BaFe_(12)O_(19)的结晶有序程度并降低其微观应变,因而可明显提高其RCP;XRD、SEM和VSM分析结果表明,RCP的提高明显有助于BaFe_(12)O_(19)片状颗粒径向尺寸和饱和磁化强度的提高;以氯化胆碱-乙二醇-水为媒介可制备性能优良的BaFe_(12)O_(19)。

关键词：钡铁氧体氯化胆碱-乙二醇化学共沉淀法均匀设计相对结晶纯度