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

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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.

Kinematics Analysis Based on Screw Theory of a Humanoid Robot

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Journal of China University of Mining and Technology 2007年第1期17卷 49-52页

作者： MAN Cui-hua fan xun LI Cheng-rong ZHAO Zhong-hui School of Mechanical Electronic and Information Engineering China University of Mining ＆ Technology Beijing 100083 China Institute of Automation Chinese Academy of Sciences Beijing 100080 China

A humanoid robot is a complex dynamic system for its idiosyncrasy. This paper aims to provide a mathematical and theoretical foundation for the design of the configuration, kinematics analysis of a novel humanoid robot. It has a simplified configuration and design for entertainment purpose. The design methods, principle and mechanism are discussed. According to the design goals of this research, there are ten degrees of freedom in the two bionic arms. Modularization, concurrent design and extension theory methods were adopted in the configuration study and screw theory was introduced into the analysis of humanoid robot kinematics. Comparisons with other methods show that: 1) only two coordinates need to be established in the kinematics analysis of humanoid robot based on screw theory; 2) the spatial manipulator Jacobian obtained by using twist and exponential product formula is succinct and legible; 3) adopting screw theory to resolve the humanoid robot arms kinematics question can avoid singularities; 4) using screw theory can solve the question of specification insufficiency.

关键词： bionics arm screw theory extension theory Jacobian matrix modularization design

How should renin-angiotensin system blockade be applied in chronic kidney disease for optimal renal protection?

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Chinese Medical Journal 2007年第3期120卷 243-245页

作者： ZHANG xun HOU fan-fan Division of Nephrology Nanfang Hospital Southern MedicalUniversity Guangzhou 510515 China

Chronic kidney disease （CKD） is a significant interactive disease in patients with diabetes,hypertension, and cardiovascular disease with major morbidity and mortality consequences and high costs to the healthcare system. CKD is characterized by a gradual loss of renal function. In most parts of the world, once end-stage renal disease （ESRD） occurs, patients who do not have access to maintenance dialysis or kidney transplantation would simply die. The data reported in the registry of the Chinese Society of Nephrology indicate that 41 000 ESRD patients were receiving dialysis in 1999, accounting for only 5% of the total population requiring renal replacement therapy.2 Delaying the progression of CKD to ESRD is an essential management goal for the clinical practice, particularly in developing countries.

关键词： renin-angiotensin system blockade chronic kidney disease

Nature inspired hierarchical structures in nano-cellular epoxy/graphene-Fe3O4 nanocomposites with ultra-efficient EMI and robust mechanical strength

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Journal of Materials Science & Technology 2022年第8期103卷 177-185页

作者： xun fan Fengchao Wang Qiang Gao Yu Zhang Fei Huang Ronglin Xiao Jianbin Qin Han Zhang Xuetao Shi Guangcheng Zhang Shaanxi Key Laboratory of Macromolecular Science and Technology School of Chemistry and Chemical EngineeringNorthwestern Polytechnical UniversityXi’an 710072PR China NPU-QMUL Joint Research Institute of Advanced Materials and Structures Northwestern Polytechnical UniversityXi’an 710072PR China Shaanxi Coal Chemical Industry Technology Research Institute Co.Ltd Xi’anShaanxi 710070PR China School of Engineering and Materials Science Queen Mary University of LondonMile End RoadLondon E14NSUK

Hierarchical layered structures,whether in a compact form like nacre or a porous manner like bone,are well known for their combined features of high stiffness,strength,and lightweight,inspiring many man-made materials and structures for high performance *** use of nacre/bone like hierarchical structures in polymer nanocomposites can achieve excellent mechanical and functional properties with high filler volume fractions after carefully aligning functional nanofillers,although the fabrication and processing remain a great *** this work,a bio-inspired lightweight nano-cellular epoxy/graphene-Fe_(3)O_(4) nanocomposite with high nanofiller loading of 75 wt.%was successfully fabricated by combining features from both nacre and bone structures,via a simple compression molding process together with an eco-friendly supercritical CO_(2) foaming process to achieve robust mechanical strength and excellent electromagnetic interference(EMI)shielding effectiveness(SE)*** aligned graphene-Fe_(3)O_(4) nanoplatelets with well controlled nanoscale porous structures(52.6 nm)enabled both low density(1.26 g/cm^(3))and high specific EMI SE>5200 dB/cm^(2)/g,as well as preserved tensile strength of 67 *** study provides a sustainable route to fabricate nature mimicked structures with high performance and high flexibility for a wide range of applications,from portable electronics to healthcare devices.

关键词： Epoxy foam Layered nano-cellular structures Graphene-Fe_(3)O_(4)nanocomposites Electromagnetic interference shielding

Construction of a Full-Length cDNA Library of Gossypium hirsutum L. and Identification of Two MADS-Box Genes

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Agricultural Sciences in China 2011年第1期10卷 28-40页

作者： WANG Li-na WU Dong YU Shu-xun fan Shu-li SONG Mei-zhen PANG Chao-you LIU Jun-jie Cotton Research Institute Chinese Academy of Agricultural Sciences~Key Laboratory of Cotton Genetic Improvement Ministry of AgricultureAnyang 455000 P.R.China

A full-length normalized cDNA library for the flower development stages of short-season cotton （Gossypium hirsutum L.）（CCRI36） was constructed. A total of 3 421 clones were randomly selected for sequencing, with a total of 3 175 effective sequences obtained after removal of empty-carriers and low-quality sequences. Clustering the 3 175 high-quality expressed sequence tags （ESTs） resulted in a set of 2 906 non-redundant sequences comprised of 233 contigs and 2 673 singletons. Comparative analyses indicated that 913 （43.6%） of the unigenes had homologues with function-known genes or functionassumed genes in the National Center for Biotechnology Information. In addition, 763 （36.4%） of the unigenes were functionally classified using Gene Ontology hierarchy. Through EST alignment and the screening method, the full-length cDNA of two MADS-box genes viz., GhMADSll and GhMADS12 were acquired. These genes may play a role in flower development. Phylogenetie analysis indicated that GhMADS11 and GhMADS12 had high homology and close evolutionary relationship with AGL2/SEP-type and PI-type genes, respectively. The expression of both GhMADSll and GhMADS12, genes was high in reproductive organs. In floral organs, GhMADSll expression was high in petals （whor12） and ovules, while GhMADS12 expression was high in petals （whor12） and stamens （whor13）. Results show that the EST strategy based on a normalized cDNA library is an effective method for gene identification. The study provides more insights for future molecular research on the regulation mechanism of cotton flower development.

关键词： cotton normalized cDNA library EST MADS-box gene

Tryptophan Modification and Fluorescence Spectrum of Hyaluronidase

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Chinese Chemical Letters 2005年第11期16卷 1492-1494页

作者： Li Rong TENG Yu Zhuo CHU Xiao Ping ZHANG Xiao Kun YU Jing WANG Song HAN Bo xun ZHANG Hao fan Lan Ying LIU College of Life Science Jilin University Changchun 130023

Tryptophan residues in hyaluronidase （HAase） were modified by N-bromosuccinimide （NBS）, the results indicated that there were eleven tryptophan residues in HAase, one of which was exposed and essential for the activity of the enzyme. The study on fluorescence quenching showed that KI could not quench all of the fluorescence from Trp residues in HAase, while acrylamide （Acr） could quench almost all of the fluorescence from Trp residues in HAase. The collisional quenching constants （KD） of HAase at different concentrations of Acr were calculated in terms of Stern-Volmer equation. The results implied that some of the Trp residues were buried in the interior of HAase and the Trp residue on the surface of HAase was not located in the hydrophobic pocket.

关键词： Hyaluronidase (HAase) tryptophan (Trp) fluorescence spectrum.

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惯性及滑移对EMP推力轴承的影响研究

中国矿业大学学报 2009年第5期38卷 665-669页

作者：范迅刘宪伟中国矿业大学机电与信息工程学院北京100083 装甲兵技术学院机械工程系吉林长春130117

为了考察界面滑移和流体惯性对水润滑弹性金属塑料(EMP)推力轴承润滑性能的影响,从连续性方程和Navier-Stokes方程出发,推导出在圆柱坐标系中考虑了界面滑移和流体惯性影响的雷诺方程,并采用有限差分法对其进行数值计算.计算结果表明:... 详细信息

为了考察界面滑移和流体惯性对水润滑弹性金属塑料(EMP)推力轴承润滑性能的影响,从连续性方程和Navier-Stokes方程出发,推导出在圆柱坐标系中考虑了界面滑移和流体惯性影响的雷诺方程,并采用有限差分法对其进行数值计算.计算结果表明:界面滑移现象的出现将降低10%左右的水膜压力和轴承承载能力,而流体惯性力的存在增大了1%左右的水膜压力和轴承承载能力;随转速的增大,界面滑移现象对水膜压力和轴承承载能力的削减程度明显增大,水膜压力和轴承承载能力将降低50%左右.

关键词： EMP推力滑动轴承界面滑移流体惯性水润滑

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水垫带式输送机水垫压力场数值模拟

煤炭学报 2007年第3期32卷 317-320页

作者：刘宪伟范迅中国矿业大学(北京)机电与信息工程学院

在对水垫带式输送机压力场理论研究的基础上,建立了水垫压力场的数学模型.用Flu-ent 6.1软件对水垫压力场的分布进行了数值模拟.研究结果表明:与传统的喷嘴平行布置方式相比,改进的喷嘴错位布置方式能够大幅度地提高水垫带式输送机的承... 详细信息

在对水垫带式输送机压力场理论研究的基础上,建立了水垫压力场的数学模型.用Flu-ent 6.1软件对水垫压力场的分布进行了数值模拟.研究结果表明:与传统的喷嘴平行布置方式相比,改进的喷嘴错位布置方式能够大幅度地提高水垫带式输送机的承载能力;减小排距和列距可以改善水垫压力场的均匀稳定性;提高带速或者增大喷嘴直径都可以提高水垫压力场的压力值.

关键词：水垫带式输送机压力场数值模拟

2005 AHA心肺复苏与心血管急诊指南在儿科应用的思考

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临床儿科杂志 2007年第11期25卷 888-889,945页

作者：樊寻梅首都医科大学附属北京儿童医院北京100045

2005美国心脏病协会(AHA)心肺复苏与心血管急诊指南是尽力在循证基础上制定的,其中基础生命支持内容改变较多,如创伤时如何开放气道;胸外心脏按压的部位和方法;减少呼吸频率及通气量,避免过度通气与保证心脏按压;按压、通气的配合;1岁及... 详细信息

2005美国心脏病协会(AHA)心肺复苏与心血管急诊指南是尽力在循证基础上制定的,其中基础生命支持内容改变较多,如创伤时如何开放气道;胸外心脏按压的部位和方法;减少呼吸频率及通气量,避免过度通气与保证心脏按压;按压、通气的配合;1岁及1岁以上小儿可用成人AED除颤等。但本指南是一个国际性的应用指南,其制定更注重可行性与实际效果及利于推广。有些内容仅为专家们达成的共识,尚缺乏科学资料支持。因此,临床更应密切观察治疗反应,在使用中总结经验;更需注意本土化,使之适合国情。强化急救意识,确立急诊思维方法,加强技能培训是当务之急。

关键词：心肺复苏指南胸外按压室颤除颤儿科自动除颤仪