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Engineering heterostructure and crystallinity of Ru/RuS_(2) nanoparticle composited with N-doped graphene as electrocatalysts for alkaline hydrogen evolution

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Chinese Chemical Letters 2021年第11期32卷 3591-3595页

作者： Xuyun Gao Bo Li Xuzhuo Sun Baofan Wu yanping hu Zhichao Ning Jun Li Ning Wang College of Chemistry and Chemical Engineering Henan University of TechnologyZhengzhou 450001China Key Laboratory of Synthetic and Natural Functional Molecule of the Ministry of Education College of Chemistry&Materials ScienceNorthwest UniversityXi'an 710069China

Crystalline engineering and heterostructure have attracted much attention as effective strategies to improve the electrocatalytic activity for hydrogen evolution reaction(HER).In this study,a new heterostructure catalyst(Ru/RuS_(2)@N-rGO)with low crystallinity was fabricated by a simple and low-temperature method for HER in alkaline solution,applying the Na_(2)SO_(4)as S source and polypyrrole as N *** through the controllable crystalline engineering and composition ratio of Ru and RuS_(2),the Ru/RuS_(2)@N-rGO heterocatalyst at the calcining 500°C revealed highly efficient HER activity with overpotential 18 mV at a current density 10 mA/cm^(2)and remarkable stability for 24 h in 1.0 mol/L *** work provides a facile and effective method in designing advanced electrocatalysts for HER in the alkaline electrolytes by synergistically structural and component modulations.

关键词： Low crystallinity Ru/RuS_(2)heterostructure Graphene Electrocatalytic hydrogen evolution Alkaline solution

Synergistic engineering of CRISPR-Cas nucleases enables robust mammalian genome editing

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The Innovation 2022年第4期3卷 74-82页

作者： Yangcan Chen yanping hu Xinge Wang Shengqiu Luo Ning Yang Yi Chen Zhikun Li Qi Zhou Wei Li State Key Laboratory of Stem Cell and Reproductive Biology Institute of ZoologyChinese Academy of SciencesBeijing 100101China University of Chinese Academy of Sciences Beijing 100049China Institute for Stem Cell and Regenerative Medicine Chinese Academy of SciencesBeijing 100101China Bejing Institute for Stem Cell and Regenerative Medicine Beijing 100101China

The naturally occurring prokaryotic CRISPR-Cas systems provide valuable resources for the development of new genome-editing ***,the majority of prokaryotic Cas nucleases exhibit poor editing efficiency in mammalian cells,which significantly limits their ***,we have developed a method termed Improving Editing Activity by Synergistic Engineering(MIDAS).This method exerts a synergistic effect to improve mammalian genome-editing efficiency of a wide range of CRISPR-Cas systems by enhancing the interactions of Cas nuclease with the protospacer adjacent motif(PAM)and the single-stranded DNA(ssDNA)substrate in the catalytic pocket *** robustly and significantly increased the gene-editing efficiency of Cas12i,Cas12b,and CasX in human ***,a Cas12i variant,Cas12iMax,exhibited robust activity with a very broad PAM range(NTNN,NNTN,NAAN,and NCAN)and higher efficiency than the current widely used Cas nucleases.A high-fidelity version of Cas12iMax(Cas12iHiFi)has been further engineered to minimize off-target *** work provides an expandable and efficacious method for engineering Cas nucleases for robust mammalian genome editing.

关键词： editing engineering mammalian

Computer-aided engineering of CRISPR-Cas proteins for enhanced human genome editing

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Science China(Life Sciences) 2023年第4期66卷 883-886页

作者： Yangcan Chen yanping hu Shengqiu Luo Xinge Wang Bangwei Mao Yi Chen Jing Xu Zhikun Li Qi Zhou Wei Li State Key Laboratory of Stem Cell and Reproductive Biology Institute of ZoologyChinese Academy of SciencesBeijing 100101China University of Chinese Academy of Sciences Beijing 100049China Institute for Stem Cell and Regenerative Medicine Chinese Academy of SciencesBeijing 100101China Bejing Institute for Stem Cell and Regenerative Medicine Beijing 100101China

Dear *** remarkably diversified CRISPR-Cas systems in nature have provided unlimited valuable resources to develop genome editing tools that are revolutionizing the fields of biotechnology and ***,due to their microbial origin,the activity of most naturally occurring CRISPR-Cas nucleases is relatively poor in mammalian cells(Ran et al.,2015).Thus,improving the mammalian genome editing efficiency becomes the priority for harnessing more CRISPRCas systems for widespread *** protein engineering serves as a powerful approach to enhance the catalytic activity of ***,this approach largely relies on proteinic three-dimension(3D)structure information as guide for *** fact is that of the large numbers of the CRISPR-Cas systems discovered in recent years,only a small number of them with the 3D structures were *** bypass this limitation,here,we report an efficient and simple strategy for rational engineering of Cas nucleases without the need of 3D structure information and successfully optimized nucleases from Cas9 and Cas12 families.

关键词： rational editor editing

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基于RAROC的贷款保险定价研究

管理评论 2017年第1期29卷 42-52页

作者：胡斌胡艳萍电子科技大学经济与管理学院成都611731 四川师范大学经济与管理学院成都610068 西南民族大学外国语学院成都610041

为风险业务配置经济资本并设定RAROC目标,是商业银行和保险公司风险管理的发展方向。以RAROC为桥梁,构建起的贷款保险定价模型,能够为贷款保险业务测算出更加符合现代风险管理要求的价格区间与价格基准,弥补了相关定价模型和方法的某些... 详细信息

为风险业务配置经济资本并设定RAROC目标,是商业银行和保险公司风险管理的发展方向。以RAROC为桥梁,构建起的贷款保险定价模型,能够为贷款保险业务测算出更加符合现代风险管理要求的价格区间与价格基准,弥补了相关定价模型和方法的某些不足,提升了贷款保险定价模型的可操作性,对拓展信贷风险转移定价问题的研究思路具有积极意义。研究建议RAROC应成为制定贷款保险价格或其他信贷风险转移价格时需要考虑的重要指标之一。

关键词：信贷风险贷款保险定价 RAROC 非预期损失经济资本

沙颍河流域一次基于高分辨资料的降水相态分析

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高原气象 2019年第5期38卷 983-992页

作者：武威胡燕平河南省漯河市气象局河南漯河462300 河南省沙颍河流域气象中心河南漯河462300

利用常规气象资料、NCEP 0.25°×0.25°分析资料以及微波辐射计、风廓线雷达等高分辨率资料,采用诊断和统计方法,对2017年2月21日沙颍河流域一次雨雪过程中降水相态进行分析。结果表明:在高空低槽与东路冷空气共同作用造成雨雪天气的... 详细信息

利用常规气象资料、NCEP 0.25°×0.25°分析资料以及微波辐射计、风廓线雷达等高分辨率资料,采用诊断和统计方法,对2017年2月21日沙颍河流域一次雨雪过程中降水相态进行分析。结果表明:在高空低槽与东路冷空气共同作用造成雨雪天气的背景下,925 hPa及以下冷高压底部的偏北冷空气造成低层持续降温,导致降水相态变化。过程前期700 hPa以下为强暖平流,冷平流在900 hPa以下且较为浅薄,温度层结为冷层-暖层-冷层-暖层,冰晶粒子下落融化形成雨滴。降水中后期冷平流发展强烈导致温度迅速下降,整层温度变为冷层,导致相态为雪;即使下游局部地区仍有暖层,但暖层浅薄、低层冷层深厚,相态也为雪。雨雪转换时0℃层高度下降明显,降雨阶段0℃层在抬升凝结高度以上,降雪阶段0℃层降到抬升凝结高度以下;0℃层亮带回波在相态转换时出现明显变化,其亮带高度逐渐降低。微波辐射计的温湿廓线、云底高度以及液态水等在雨雪转换中均有显著变化,液态水含量在雨雪转变时迅速增大。风廓线风场定性反映了冷空气持续南下,低层冷垫增厚,导致相态转变以及降水强度增加;风廓线速度定量反映出降雨和降雪之间的差异,降雨速度范围为1.5~7.0 m·s^-1,降雪速度范围在0.25~1.5 m·s^-1;雨雪转换时下落速度明显减小,可用于相态转变的监测和预报。

关键词：降水相态温度平流 0℃层微波辐射计风廓线雷达

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中小企业融资交易成本分摊的思路探析

科技管理研究 2006年第8期26卷 97-99,117页

作者：胡延平辽宁大学经济学院辽宁沈阳110036

通过改善融资制度环境和提高融资制度效率,政府针对中小企业融资的公共服务是一种有效的分摊融资交易成本的方式。但是,由于我国国有银企之间关系型融资制度所具有的两个特征:一是银企交易成本内部化,二是中小企业长期处在这种融资制度... 详细信息

通过改善融资制度环境和提高融资制度效率,政府针对中小企业融资的公共服务是一种有效的分摊融资交易成本的方式。但是,由于我国国有银企之间关系型融资制度所具有的两个特征:一是银企交易成本内部化,二是中小企业长期处在这种融资制度的视线之外,造成了政府一直不重视公共服务的作用,使中小企业缺乏一个有效的成本分摊机制来解决融资困境。本文认为通过提供更多的有针对性的公共服务是解决我国中小企业融资困境的一个可行的思路。

关键词：融资制度公共服务中小企业交易成本分摊

Yields,growth and water use under chemical topping in relations to row configuration and plant density in drip-irrigated cotton

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Journal of Cotton Research 2024年第2期7卷 123-136页

作者： Wang Xuejiao hu yanping Ji Chunrong Chen Yongfan Sun Shuai Zhang Zeshan Zhang Yutong Wang Sen Yang Mingfeng Ji Fen Guo Yanyun Li Jie Zhang Lizhen Xinjiang Agriculture Network Information Center Xinjiang Agrometeorological ObservatoryUrumqi 830002China College of Resources and Environmental Sciences Xinjiang Agricultural UniversityUrumqi 830091China College of Resources and Environmental Sciences China Agricultural UniversityBeijing 100193China China Meteorological Administration Institute of Desert MeteorologyUrumqi 830002China Wulanwusu Agrometeorological Station Shihezi 832199China Xinjiang Academy of Agricultural Sciences China National Cotton R&D CenterUrumqi 830091China

Background Water deficit is an important problem in agricultural production in arid *** the advent of wholly mechanized technology for cotton planting in Xinjiang,it is important to determine which planting mode could achieve high yield,fiber quality and water use efficiency(WUE).This study aimed to explore if chemical topping affected cotton yield,quality and water use in relation to row configuration and plant *** Experiments were carried out in Xinjiang China,in 2020 and 2021 with two topping method,manual topping and chemical topping,two plant densities,low and high,and two row configurations,i.e.,76 cm equal rows and 10+66 cm narrow-wide rows,which were commonly applied in matching harvest *** topping increased seed cotton yield,but did not affect cotton fiber quality comparing to traditional manual *** equal row spacing,the WUE in higher density was 62.4%higher than in the lower ***,under narrow-wide row spacing,the WUE in lower density was 53.3%higher than in higher one(farmers’practice).For machine-harvest cotton in Xinjiang,the optimal row configuration and plant density for chemical topping was narrow-wide rows with 15 plants m-2 or equal rows with 18 plants *** The plant density recommended in narrow-wide rows was less than farmers’practice and the density in equal rows was moderate with local *** results provide new knowledge on optimizing agronomic managements of machine-harvested cotton for both high yield and water efficient.

关键词： Yield components Fiber quality Transpiration Water use efficiency Heat ratio method(HRM)

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变桨距风力发电机额定风速的确定方法

太阳能学报 2011年第3期32卷 307-310页

作者：胡燕平甄海华戴巨川湖南科技大学机电工程学院湘潭411201

根据风速的Weibull分布特性和变桨距风力发电机的发电特性,构建不同额定风速下风力发电机年发电量计算方法。应用美国可再生能源实验室(NREL)对风力发电成本的研究成果,建立了变桨距风力发电机发电的度电成本数学模型,提出了以度电成本... 详细信息

根据风速的Weibull分布特性和变桨距风力发电机的发电特性,构建不同额定风速下风力发电机年发电量计算方法。应用美国可再生能源实验室(NREL)对风力发电成本的研究成果,建立了变桨距风力发电机发电的度电成本数学模型,提出了以度电成本最低为目标的额定风速确定方法,为变桨距风力发电机的额定风速最优选择提供了计算依据。

关键词：变桨距风力发电机额定风速度电成本

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大型风力机叶片研究现状与发展趋势

机械工程学报 2013年第20期49卷 140-151页

作者：胡燕平戴巨川刘德顺湖南科技大学机械设备健康维护省重点实验室湘潭411201

叶片是风力机最为关键的部件之一,叶片、轮毂组成的风轮是能量捕获机构,将风能转变为机械能,与此同时,叶片又是风力机力源,主要承载部件,对整个风力机安全运行起着关键作用。在对大型风力机及其叶片产业发展现状分析基础上,从气动外形... 详细信息

叶片是风力机最为关键的部件之一,叶片、轮毂组成的风轮是能量捕获机构,将风能转变为机械能,与此同时,叶片又是风力机力源,主要承载部件,对整个风力机安全运行起着关键作用。在对大型风力机及其叶片产业发展现状分析基础上,从气动外形与结构设计现状、运行监测与控制技术现状、发展趋势与有待研究的问题等几个角度进行较为全面的梳理总结,从而从总体上把握现代大型风力机叶片研究现状及发展趋势。指出今后将在针对抗台风叶片、低风速叶片、仿生叶片和低噪音叶片等的个性化设计,具有外部载荷环境和自身结构状态变化感知功能的智能风力机叶片设计等方面进一步发展;已经形成的风力机叶片设计、制造及运行监控理论等还要随着大批量风力机全生命周期服役实践,进一步完善和发展。

关键词：风力机叶片设计能量捕获运行监控全生命周期