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A Solvent-Free Covalent Organic Framework Single-Ion Conductor Based on Ion-Dipole Interaction for All-Solid-State Lithium Organic Batteries
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作者 Zhongping li Kyeong-Seok Oh +6 位作者 Jeong-Min Seo Wenliang Qin Soohyoung Lee lipeng Zhai changqing li Jong-Beom Baek Sang-Young Lee 《Nano-Micro Letters》 SCIE EI CAS CSCD 2024年第12期189-200,共12页
Single-ion conductors based on covalent organic frameworks(COFs)have garnered attention as a potential alternative to currently prevalent inorganic ion conductors owing to their structural uniqueness and chemical vers... Single-ion conductors based on covalent organic frameworks(COFs)have garnered attention as a potential alternative to currently prevalent inorganic ion conductors owing to their structural uniqueness and chemical versatility.However,the sluggish Li+conduction has hindered their practical applications.Here,we present a class of solvent-free COF single-ion conductors(Li-COF@P)based on weak ion-dipole interaction as opposed to traditional strong ion-ion interaction.The ion(Li+from the COF)-dipole(oxygen from poly(ethylene glycol)diacrylate embedded in the COF pores)interaction in the Li-COF@P promotes ion dissociation and Li+migration via directional ionic channels.Driven by this single-ion transport behavior,the Li-COF@P enables reversible Li plating/stripping on Li-metal electrodes and stable cycling performance(88.3%after 2000 cycles)in organic batteries(Li metal anode||5,5’-dimethyl-2,2’-bis-p-benzoquinone(Me2BBQ)cathode)under ambient operating conditions,highlighting the electrochemical viability of the Li-COF@P for all-solid-state organic batteries. 展开更多
关键词 Solid organic single-ion conductors Solvent-free covalent organic frameworks All-solid-state Li organic batteries Ion-dipole interaction Pore functionalization
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Copolymerization of Acrylonitrile/1-Vinyl-3-Ethylimidazolium Bromide and Rheological, Thermal Properties of the Copolymer 被引量:2
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作者 Yuanjian Tong Bowen Zhang +1 位作者 changqing li lianghua Xu 《Transactions of Tianjin University》 EI CAS 2019年第1期85-90,共6页
Acrylonitrile(AN)/1-vinyl-3-ethylimidazolium bromide(VIMB) copolymer was prepared via solution polymerization using dimethyl sulfoxide(DMSO) as a solvent and azodiisobutyronitrile as an initiator. The effects of comon... Acrylonitrile(AN)/1-vinyl-3-ethylimidazolium bromide(VIMB) copolymer was prepared via solution polymerization using dimethyl sulfoxide(DMSO) as a solvent and azodiisobutyronitrile as an initiator. The effects of comonomer VIMB on the polymerization, rheological properties of the polymer solution and thermal properties of the copolymer were investigated. The ionic liquid VIMB resulted in higher polymerization conversion ratio and higher average molecular weight when copolymerized with AN than itaconic acid(ITA). Rheological measurements indicated that the transition shear rate increased linearly with increasing temperature for P(AN/ITA)/DMSO solution, while an exponential growth with temperature was observed for P(AN/VIMB)/DMSO solution. The exothermic peaks of DSC curves in N_2 appeared at 276.67 and 257.34 °C for P(AN/VIMB) and P(AN/ITA), respectively. As a potential comonomer of AN for PAN carbon fibers, the VIMB resulted in about 7% higher char yield in N_2, and 23.7% less weight loss at 600 °C in air than ITA copolymer. 展开更多
关键词 Carbon fiber COPOLYMER POLYACRYLONITRILE Ionic liquid THERMAL properties
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A Comparative Study for the Development of Coal-to-Liquids Industries in China, South Africa and United States
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作者 Yiming li changqing li 《Green and Sustainable Chemistry》 2019年第3期85-93,共9页
Many energy consuming countries have carried out research, development, demonstration, planning and deployment of coal-to-liquids (CTL) because of its ability to replace oil imports by converting coal resources into f... Many energy consuming countries have carried out research, development, demonstration, planning and deployment of coal-to-liquids (CTL) because of its ability to replace oil imports by converting coal resources into fuel. Among them, China and South Africa successfully had their CTL technology industrialized, while the United States did not. To understand the differences in the industrial development level, a comparative study is necessary. This paper compares the history, driver and policy of CTL industry in China, South Africa and United States, collates and discloses numbers of industry details for the first time. We figure out that the motivation, top level planning and policy consistency are the key indicators of the difference on the industrial development level. Among them, the key to the success of CTL industrialization in China and South Africa is the government’s strong and stable determination to improve energy security, which provides a stable top-level planning and robust policy support. The failure of CTL in United States is caused by the shift of policy attention after its energy security situation improved. 展开更多
关键词 Coal-to-Liquids Comparative Study China UNITED STATES SOUTH AFRICA
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Methane dry reforming on Ni/La_2Zr_2O_7 treated by plasma in different atmospheres 被引量:4
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作者 Honggen Peng Youhe Ma +7 位作者 Wenming liu Xianglan Xu Xiuzhong Fang Jie lian Xiang Wang changqing li Wufeng Zhou Ping Yuan 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2015年第4期416-424,共9页
A series of Ni/La2Zr2O7 pyrochlore catalysts prepared by impregnation method and treated by dielectric barrier discharge(DBD) plasma in different atmospheres and varied sequences were prepared and applied for dry re... A series of Ni/La2Zr2O7 pyrochlore catalysts prepared by impregnation method and treated by dielectric barrier discharge(DBD) plasma in different atmospheres and varied sequences were prepared and applied for dry reforming of methane(DRM). It is found that all of the plasma treated catalysts show evidently improved activity and coke resistance in comparison with the non-plasma treated one. The best performance is achieved on Ni/La2Zr2O7–H2P–C,a catalyst treated in H2 plasma before calcination. TGA-DSC and SEM demonstrate that carbon deposition is significantly suppressed on all of the plasma treated samples. Moreover,XRD and TEM results testify that both Ni O and Ni sizes on the calcined and reduced samples treated by plasma are also decreased,which results in higher Ni metal dispersion on the reduced and used catalysts and enhances the interactions between Ni sites and the support. It is believed that these are the inherent reasons accounting for the promotional effects of plasma treatment on the reaction performance of the Ni/La2Zr2O7 pyrochlore catalysts. 展开更多
关键词 Methane dry reforming Ni-based catalysts Pyrochlore support DBD plasma Coke resistance
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Dry reforming of methane on active and coke resistant Ni/Y_2Zr_2O_7 catalysts treated by dielectric barrier discharge plasma 被引量:3
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作者 Xiuzhong Fang Jie lian +7 位作者 Kaiwen Nie Xianhua Zhang Yanfeng Dai Xianglan Xu Xiang Wang Wenming liu changqing li Wufeng Zhou 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2016年第5期825-831,共7页
In this study, Ni/YZrOcatalysts prepared with impregnation method and treated by dielectric barrier discharge plasma(DBD) in different atmospheres have been investigated for methane dry reforming. It is revealed by H-... In this study, Ni/YZrOcatalysts prepared with impregnation method and treated by dielectric barrier discharge plasma(DBD) in different atmospheres have been investigated for methane dry reforming. It is revealed by H-TPR that plasma treatment can enhance the interaction between Ni O/Ni particles and the YZrOpyrochlore support. Therefore, catalysts with smaller Ni O and Ni grains sizes, higher metallic Ni active surface areas can be achieved, as evidenced by XRD, TEM and Hadsorption-desorption measurements. As a consequence, the plasma-treated catalysts show significantly improved activity, stability and coke resistance, as testified by the TEM and TGA-DSC results. Plasma treatment in H/Ar gas mixture is found to be the best condition to prepare Ni/YZrO, which can be used to obtain a catalyst with the highest activity, stability and most potent coke resistance. It is believed that the smaller Ni grain size and higher metallic Ni active surface area induced by plasma treatment are the inherent reasons accounting for the promoted reaction performance of the Ni/YZrOpyrochlore catalysts. 展开更多
关键词 Plasma treatment Y2Zr2O7 pyrochlore support Supported Ni catalysts Methane dry reforming Coke resistance
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Research on the Power System Fault Classification Based on HHT and SVM Using Wide-area Information 被引量:1
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作者 Yiran Guo changqing li +1 位作者 Yali li Shibin Gao 《Energy and Power Engineering》 2013年第4期138-142,共5页
A power system fault classification method based on the Hilbert-Huang transformation (HHT) and support vector machine (SVM) is proposed in this paper. According to different types of faults taking place in area and th... A power system fault classification method based on the Hilbert-Huang transformation (HHT) and support vector machine (SVM) is proposed in this paper. According to different types of faults taking place in area and the outer area, this paper uses HHT to extract the instantaneous amplitude and Hilbert marginal spectrum of the current signal. Then a fault classifier consisting of a series of SVM classifiers that are optimized by using cross validation method is constructed. Finally, inputting the feature vector sets that are conversed by the HHT into the fault classifier, the fault type and locate the fault area will be distinguished. The simulation results show that this approach is very effective to classify the fault type especially when the sample is small. 展开更多
关键词 Power System FAULT Classification HHT SVM Cross-validation
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Accurate Registration of Remote Sensing Images Based on Local Optimal Transformation
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作者 Bo Wang changqing li +2 位作者 Shi Tang Zhiqiang Zhou Hong Zhao 《Journal of Beijing Institute of Technology》 EI CAS 2019年第2期371-382,共12页
As the basic work of image stitching and object recognition,image registration played an important part in the image processing field.Much previous work in registration accuracy and realtime performance progressed ver... As the basic work of image stitching and object recognition,image registration played an important part in the image processing field.Much previous work in registration accuracy and realtime performance progressed very slowly,especially in registrating images with line feature.An innovative method for image registration based on lines is proposed,it can effectively improve the accuracy and real-time performance of image registration.The line feature can deal with some registration problems where point feature does not work.Our registration process is divided into two parts.The first part determines the rough registration transformation relation between reference image and test image.Then the similarity degree among different transformation and modified nonmaximum suppression(MNMS)algorithms are obtained,which produce local optimal solution to optimize the rough registration transformation.The final optimal registration relation can be obtained from two registration parts according to the match scores.The experimental results show that the proposed method makes a more accurate registration relation and performs better in real-time situation. 展开更多
关键词 initial REGISTRATION RELATIONSHIP accurate REGISTRATION RELATIONSHIP SIMILARITY degree local optimal TRANSFORMATION modified non-maximum suppression(MNMS)algorithm
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Biotinylated dextran amine as a neural tracer in the rat corticospinal tract
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作者 Biao Gong changqing li +1 位作者 Xiaofeng li Ying Wang 《Neural Regeneration Research》 SCIE CAS CSCD 2008年第3期237-240,共4页
BACKGROUND: The corticospinal tract is the core structure of cerebral control of extremity movement and plasticity, which are prerequisites for movement rehabilitation after brain injury. The measurement and assessme... BACKGROUND: The corticospinal tract is the core structure of cerebral control of extremity movement and plasticity, which are prerequisites for movement rehabilitation after brain injury. The measurement and assessment of plasticity changes within the corticospinal tract has become one of the key goals in this field. OBJECTIVE: To explore the effects of biotinylated dextran amine (BDA) as a neural tracer in the rat corticospinal tract and the possibilities of assessing plasticity within the corticospinal tract. DESIGN: An observational experiment. SETTING: Department of Acupuncture of Chinese Medical College, Chongqing Medical University, Department of Neurology, the Second Affiliated Hospital, Chongqing Medical University. MATERIALS: Eighteen male adult Sprague Dawley (SD) rats of clean grade, weighing 200-250 g, were provided by the experimental animal center of Chongqing Medical University. The animal procedures in this study were in accordance with the animal ethics standards. BDA was provided by Vector Laboratories Company (USA, catalogue Sp- 1140; serial number R0721 ). METHODS. This experiment was performed in the Laboratory of Chongqing Medical University between September and December 2006. Adult SD rats were used in the experiment and 15% BDA was injected slowly with a mini-syringe through two round (3 mm diameter) holes into the left sensory and motor cortex. The center of one hole was located 3 mm anterior from the anterior fontanel and 1.5 mm left of the midline; the second hole was located 1.5 mm posterior from the anterior fontanel and 4 mm left of the midline. Three injections were made at each hole at three different levels: 1.4, 1.2, and 1 mm ventral from the surface of the flat skull. After 14 days, the brains and spinal cords were removed and frozen. Sections were cut on a cryostat and BDA transportation absorbed by axons was observed under a fluorescence microscope. MAIN OUTCOME MEASURES: Axonal absorption and transportation of BDA was observed under fluorescence microscope. RESULTS: Eighteen SD rats were enrolled in this experiment; 12 rats were included in the final analysis and six were eliminated, resulting in a dropout rate of 33% (6/18). BDA injected into the left cortex was absorbed in the axons, and fluorescence was observed throughout the pyramidal neurons and axons of the left cerebral cortex. At 14 days after rejection, BDA was detected in the midbrain and cervical enlargement along the CST, and axonal structures and Ranvier nodes were clearly observed with 200x magnification. CONCLUSION: BDA injected into the cerebral cortex effectively traces the corticospinal tract and is biologically stable over long distance transportation. In addition, the method of BDA tracing is fairly simple to perform. 展开更多
关键词 biotinylated dextran amine neural tracer corticospinal tract neural tissue engineering
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The Analysis of Bilateral Power Supply for AC Electrified Railway
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作者 Zhengqing Han Zhen Fang +1 位作者 changqing li Dong li 《Energy and Power Engineering》 2013年第4期483-487,共5页
In China, the unilateral power supply has been used in AC electrified railway, which depends on the management mode of power system. For better economic and technical indexes, all-parallel AT traction system is widely... In China, the unilateral power supply has been used in AC electrified railway, which depends on the management mode of power system. For better economic and technical indexes, all-parallel AT traction system is widely used in passenger dedicated line. In this paper, the equivalent circuit model of unilateral power supply and bilateral power supply is investigated, and based on this model, the difference between unilateral power supply impedance and bilateral power supply impedance is discussed. 展开更多
关键词 All-parallel AT TRACTION SYSTEM BILATERAL POWER Supply SYSTEM ANALYSIS UNILATERAL POWER Supply
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A Surfing Concurrence Transaction Model for Key-Value NoSQL Databases
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作者 changqing li Jianhua Gu 《Journal of Software Engineering and Applications》 2018年第10期467-485,共19页
As more and more application systems related to big data were developed, NoSQL (Not Only SQL) database systems are becoming more and more popular. In order to add transaction features for some NoSQL database systems, ... As more and more application systems related to big data were developed, NoSQL (Not Only SQL) database systems are becoming more and more popular. In order to add transaction features for some NoSQL database systems, many scholars have tried different techniques. Unfortunately, there is a lack of research on Redis’s transaction in the existing literatures. This paper proposes a transaction model for key-value NoSQL databases including Redis to make possible allowing users to access data in the ACID (Atomicity, Consistency, Isolation and Durability) way, and this model is vividly called the surfing concurrence transaction model. The architecture, important features and implementation principle are described in detail. The key algorithms also were given in the form of pseudo program code, and the performance also was evaluated. With the proposed model, the transactions of Key-Value NoSQL databases can be performed in a lock free and MVCC (Multi-Version Concurrency Control) free manner. This is the result of further research on the related topic, which fills the gap ignored by relevant scholars in this field to make a little contribution to the further development of NoSQL technology. 展开更多
关键词 NOSQL Big Data SURFING CONCURRENCE TRANSACTION Model KEY-VALUE NOSQL Databases REDIS
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An Anionic Covalent Organic Framework as an Electrostatic Molecular Rectifier for Stabilizing Mg Metal Electrodes
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作者 Zhongping li Hyunseok Moon +5 位作者 Seok-Kyu Cho changqing li Jeong-Min Seo Jong-Beom Baek Hong Xu Sang-Young Lee 《CCS Chemistry》 CSCD 2023年第11期2567-2575,共9页
Despite its potential as a high-capacity battery electrode,magnesium(Mg)metals are highly susceptible to electrolytes,resulting in the formation of unwanted passivation layers,which hinder charge transfer phenomena.He... Despite its potential as a high-capacity battery electrode,magnesium(Mg)metals are highly susceptible to electrolytes,resulting in the formation of unwanted passivation layers,which hinder charge transfer phenomena.Here,we first report an anionic covalent organic framework(a-COF)as an electrostatic molecular rectifier(that can preferentially trap solvent molecules)to stabilize Mg metal electrodes.Compared to a neutral COF(n-COF)as a control sample,the a-COF enhances Mg^(2+)transport by facilitating the desolvation of Mg^(2+)-solvent complexes and cationic mobility through its negatively charged one-dimensional columns,thereby achieving an ionic conductivity eight times higher than that of the n-COF.In addition,the anionic porous frameworks in contact with Mg metal electrodes enable a uniform Mg^(2+)flux and interfacial stability with Mg metal electrodes.Consequently,the a-COF exhibited reversible Mg plating/stripping cyclability on Mg metal electrodes compared to the n-COF,demonstrating the electrochemical viability of the anionic frameworks for Mg metal electrode stabilization. 展开更多
关键词 anionic covalent organic framework Mg metal electrodes ion transport interfacial stability Mg plating/stripping
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Study on the Strategy of Pricing for Enterprise Merger and Acquisition
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作者 changqing li Yan Zheng 《Chinese Business Review》 2004年第7期54-59,共6页
Enterprise merger and acquisition is one of the property right exchanges. This paper researches the strategy of pricing for enterprise merger and acquisition, displays finance decision-making model, program and method.
关键词 enterprise merger and acquisition strategy of pricing auction
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澎溪河消落带大型土壤动物群落分布格局及其影响因素
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作者 马骅 李常青 +3 位作者 余品锋 陈杰 贺天耀 王可洪 《生物多样性》 CAS CSCD 北大核心 2024年第7期54-64,共11页
消落带是水体与陆地之间的过渡区域,生态过程独特,生物多样性较高,对环境变化非常敏感。土壤动物是消落带生态系统的重要组成部分,发挥着重要的生态功能。研究消落带土壤动物多样性对充分评估大型水利水电工程对生态环境的影响至关重要... 消落带是水体与陆地之间的过渡区域,生态过程独特,生物多样性较高,对环境变化非常敏感。土壤动物是消落带生态系统的重要组成部分,发挥着重要的生态功能。研究消落带土壤动物多样性对充分评估大型水利水电工程对生态环境的影响至关重要。本文通过对澎溪河消落带8个地点和4个高程大型土壤动物群落及其环境要素的野外调查,结合冗余分析(redundancyanalysis,RDA)探讨其关键影响因素,运用扩散生态位连续体指数(dispersal-nichecontinuumindexes,DNCI)探讨扩散过程和生态位分化在土壤动物群落多样性维持中的相对重要性。结果表明,澎溪河消落带大型土壤动物共有16目77科57,072只,以马陆、鼠妇等腐食性类群和蜘蛛、步甲等捕食性类群为主。土壤动物多度和丰度沿河流流向和高程都呈现出先增加后降低的趋势,多样性指数和优势度指数趋势相反。捕食者相对多度随高程增加而降低,腐食者变化趋势与此相反。消落带大型土壤动物群落在垂向尺度上表现出明显的空间分布格局,采样地点对群落结构和功能组成无显著影响。水文情势和土壤理化性质的总解释量分别为31.53%和14.36%,共同效应分别为15.43%和14.05%,单独效应分别为16.10%和0.31%。消落带生境(150–170m)中物种扩散过程的重要性显著高于生态位分化,陆地生境(180m)中二者无显著差异。水文情势是消落带土壤动物群落组成、结构及其空间格局的关键影响因素。消落带与陆地之间生物迁移扩散是消落带土壤动物群落多样性维持的主要途径。研究结果可为消落带生物多样性的保护和恢复提供重要的科学依据。 展开更多
关键词 大型土壤动物 三峡水库消落带 水位变化 生物多样性
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Erratum to:Efficient and stable perovskite solar cells by build-inπ-columns and ionic interfaces in covalent organic frameworks
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作者 Riming Nie Xiaokai Chen +7 位作者 Zhongping li Weicun Chu Si Ma changqing li Xiaoming liu Yonghua Chen Zhuhua Zhang Wanlin Guo 《Nano Research》 SCIE EI CSCD 2024年第5期4639-4640,共2页
Erratum to Nano Research,2023,16(7):9387-9397 htps:/oi.or/0.100/1274-023-5603-040(1)One sentence in the article was unfortunately mispresented on page 9392.Instead of As shown in Fig.S19 in the ESM,the A2/A2 values of... Erratum to Nano Research,2023,16(7):9387-9397 htps:/oi.or/0.100/1274-023-5603-040(1)One sentence in the article was unfortunately mispresented on page 9392.Instead of As shown in Fig.S19 in the ESM,the A2/A2 values of the reference,N-COF,and C-COF samples were 45.52%,44.55%,and 45.05%,respectively. 展开更多
关键词 COF COLUMNS PEROVSKITE
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Estimation of herbage intake and digestibility of grazing sheep in Zhenglan Banner of Inner Mongolia by using n-alkanes 被引量:10
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作者 changqing li Alatengdalai +2 位作者 Shuyuan Xue Atsushi Tajima Naoto Ishikawa 《Animal Nutrition》 SCIE 2015年第4期324-328,共5页
To reveal the seasonal dynamics of herbage intake, diet composition and digestibility and clarify the relationship of those with herbage nutrient and botanical composition of grazing sheep in Zhenglan Banner of Inner ... To reveal the seasonal dynamics of herbage intake, diet composition and digestibility and clarify the relationship of those with herbage nutrient and botanical composition of grazing sheep in Zhenglan Banner of Inner Mongolia, the n-alkane technique was used to test in sheep grazed during June, August and December. The results showed that the sheep mainly ate Fringed sagebrush, Stipa krylovii and Carex in proportions of 33.5,17.9 and 21.2%, respectively, in spring. In summer, the sheep consumed cleistogenes,Potentilla tanacetifolia, Thyme, etc; the intake of Fringed sagebrush, Carex and Stipa declined. In winter,Fringed sagebrush accounted for 50.1% of herbage intake, and the intakes of Cleistogenes and Stipa krylovii increased to 15.3 and 18.4%, respectively. Herbage intake by the sheep in spring was 1.8 kg DM/d, and digestibility was 71.4%. Herbage intake and digestibility decreased slightly to 1.7 kg DM/d and 68.4%during the summer, respectively and decreased significantly to 1.2 kg DM/d and 36.4% in winter. There were significant correlations between diet composition and CP content in winter, diet composition and botanical composition in summer. A highly positive correlation between herbage intake and digestibility was observed in grazing sheep. 展开更多
关键词 N-alkane technique Diet composition Grazing sheep Herbage intake
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Family control,institutional environment and cash dividend policy:Evidence from China 被引量:15
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作者 Zhihua Wei Shinong Wu +1 位作者 changqing li Wei Chen 《China Journal of Accounting Research》 2011年第Z1期29-46,共18页
Using a sample of 1486 Chinese A-share listed companies for the period 2004-2008,this study empirically tests the impact of family control,institutional environment and their interaction on the cash dividend policy of... Using a sample of 1486 Chinese A-share listed companies for the period 2004-2008,this study empirically tests the impact of family control,institutional environment and their interaction on the cash dividend policy of listed companies.Our results indicate that(1)family firms have a lower cash dividend payout ratio and propensity to pay dividends than non-family firms;(2) a favorable regional institutional environment has a significant positive impact on the cash dividend payout ratio and propensity to pay dividends of listed companies;and(3) the impact of the regional institutional environment on cash dividends is stronger in family firms than in non-family firms.Somewhat surprisingly,we find that controlling family shareholders in China may intensify Agency Problem Ⅰ(the owner-manager conflict) rather than Agency Problem Ⅱ(the controlling shareholder-minority shareholder conflict),and thus have a significant negative impact on cash dividend policy.In contrast,a favorable regional institutional environment plays a positive corporate governance role in mitigating Agency Problem 1 and encouraging family firms to pay cash dividends. 展开更多
关键词 Family control Institutional environment Cash dividend Corporate governance
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Efficient and stable perovskite solar cells by build-inπ-columns and ionic interfaces in covalent organic frameworks
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作者 Riming Nie Xiaokai Chen +7 位作者 Zhongping li Weicun Chu Si Ma changqing li Xiaoming liu Yonghua Chen Zhuhua Zhang Wanlin Guo 《Nano Research》 SCIE EI CSCD 2023年第7期9387-9397,共11页
Perovskite solar cells(PSCs)have attracted much attention due to their rapidly increased power conversion efficiencies,however,their inherent poor long-term stability hinders their commercialization.The degradation of... Perovskite solar cells(PSCs)have attracted much attention due to their rapidly increased power conversion efficiencies,however,their inherent poor long-term stability hinders their commercialization.The degradation of PSCs first comes from the degradation of hole transport materials(HTMs).Here,we report the construction of periodicπ-columnar arrays and ionic interfaces over the skeletons by introducing cationic covalent organic frameworks(C-COFs)to the HTM.Periodicπ-columnar arrays can optimize the charge transport ability and energy levels of the hole transport layer and suppress the degradation of HTM,and ionic interfaces over the skeletons can produce stronger electric dipole and electrostatic interactions,as well as higher charge densities.The C-COFs were designed and synthesized via Schiff base reaction by using 1,3,5-triformylphloroglucinol as a neutral knot and dimidium bromide as cationic linker.The neutral COFs(N-COFs)were also synthesized as a reference by using 3,8-diamino-6-phenylphenanthridine as neutral linker.PSCs with cationic COF exhibit the highest efficiency of 23.4%with excellent humidity and thermal stability.To the best of our knowledge,this is the highest efficiency among the meso-structured PSCs fabricated by a sequential process. 展开更多
关键词 cationic covalent organic framework(C-COF) π-columnar arrays ionic interfaces charge density perovskite solar cells
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Efficient and Specific Modifications of the Drosophila Genome by Means of an Easy TALEN Strategy 被引量:44
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作者 Jiyong liu changqing li +9 位作者 Zhongsheng Yu Peng Huang Honggang Wu Chuanxian Wei Nannan Zhu Yan Shen Yixu Chen Bo Zhang Wu-Min Deng Renjie Jiao 《Journal of Genetics and Genomics》 SCIE CAS CSCD 2012年第5期209-215,共7页
Technology development has always been one of the forces driving breakthroughs in biomedical research. Since the time of Thomas Morgan, Drosophilists have, step by step, developed powerful genetic tools for manipulati... Technology development has always been one of the forces driving breakthroughs in biomedical research. Since the time of Thomas Morgan, Drosophilists have, step by step, developed powerful genetic tools for manipulating and functionally dissecting the Drosophila genome, but room for improving these technologies and developing new techniques is still large, especially today as biologists start to study systematically the functional genomics of different model organisms, including humans, in a high-throughput manner. Here, we report, for the first time in Drosophila, a rapid, easy, and highly specific method for modifying the Drosophila genome at a very high efficiency by means of an improved transcription activator-like effector nuclease (TALEN) strategy. We took advantage of the very recently developed "unit assembly" strategy to assemble two pairs of specific TALENs designed to modify the yellow gene (on the sex chromosome) and a novel autosomal gene. The mRNAs of TALENs were subsequently injected into Drosophila embryos. From 31.2% of the injected Fo fertile flies, we detected inheritable modification involving the yellow gene. The entire process from construction of specific TALENs to detection of inheritable modifications can be accomplished within one month. The potential applications of this TALEN-mediated genome modification method in Drosophila are discussed. 展开更多
关键词 TALEN DROSOPHILA Genomic modification Unit assembly Reverse genetics
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Drosophila RecQ5 is required for efficient SSA repair and suppression of LOH in vivo 被引量:5
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作者 Yixu Chen Wen Dui +3 位作者 Zhongsheng Yu changqing li Jun Ma Renjie Jiao 《Protein & Cell》 SCIE CSCD 2010年第5期478-490,共13页
RecQ5 in mammalian cells has been suggested to suppress inappropriate homologous recombination.However,the specific pathway(s)in which it is involved and the underlining mechanism(s)remain poorly understood.We took ad... RecQ5 in mammalian cells has been suggested to suppress inappropriate homologous recombination.However,the specific pathway(s)in which it is involved and the underlining mechanism(s)remain poorly understood.We took advantage of genetic tools in Drosophila to investigate how Drosophila RecQ5(dRecQ5)functions in vivo in homologous recombination-mediated double strand break(DSB)repair.We generated null alleles of dRecQ5 using the targeted recombination technique.The mutant animals are homozygous viable,but with growth retardation during development.The mutants are sensitive to both exogenous DSB-inducing treatment,such as gamma-irradiation,and endogenously induced double strand breaks(DSBs)by I-Sce I endonuclease.In the absence of dRecQ5,single strand annealing(SSA)-mediated DSB repair is compromised with compensatory increases in either inter-homologous gene conversion,or non-homologous end joining(NHEJ)when inter-chromosomal homologous sequence is unavailable.Loss of function of dRecQ5 also leads to genome instability in loss of heterozygosity(LOH)assays.Together,our data demonstrate that dRecQ5 functions in SSA-mediated DSB repair to achieve its full efficiency and in suppression of LOH in Drosophila. 展开更多
关键词 Drosophila RecQ5 double strand break repair homologous recombination nonhomologous end joining single strand annealing RecQ helicase
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NDRG4 prevents cerebral ischemia/reperfusion injury by inhibiting neuronal apoptosis 被引量:8
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作者 Lan Wen Lei liu +4 位作者 linyan Tong Jinfang li Keming Zhang Qinbin Zhang changqing li 《Genes & Diseases》 SCIE 2019年第4期448-454,共7页
Cerebral ischemia is a major cause of mortality and long-term morbidity worldwide.NDRG4 has been shown to protect against cerebral ischemia,although the underlying mechanisms remain largely unclear.Here we found that ... Cerebral ischemia is a major cause of mortality and long-term morbidity worldwide.NDRG4 has been shown to protect against cerebral ischemia,although the underlying mechanisms remain largely unclear.Here we found that NDRG4 expression was decreased in the brain tissues of ischemia/reperfusion(IR)rats,indicating increased apoptosis rates among cerebral cells.NDRG4 restoration via an adenovirus significantly attenuated cerebral infarct sizes and impairments in IR rats.Furthermore,adenovirus-mediated NDRG4 inhibited cell apoptosis in the brains of IR rats and regulated the expression of Bcl-2,Bax,caspase-3,and c-Fos.Moreover,we found that NDRG4 increased expression of BDNF,which is strongly related to cerebral ischemia and cellular apoptosis.Altogether,our findings demonstrate that NDRG4 protects cerebral IR injury by inhibiting cell apoptosis and regulates cerebral cell apoptosis by increasing BDNF expression.These results suggest that NDRG4 may be a therapeutic target for IR treatment. 展开更多
关键词 APOPTOSIS BDNF ISCHEMIA NDRG4 Reperfusion injury
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