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Improving lipid production by Rhodotorula glutinis for renewable fuel production based on machine learning

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Frontiers of Chemical Science and Engineering 2024年第5期18卷 23-35页

作者： lihe Zhang Changwei Zhang Xi Zhao Changliu He xu Zhang National Energy R&D Center for Biorefinery Beijing University of Chemical TechnologyBeijing 100029China Collage of Life Science and Technology Beijing University of Chemical TechnologyBeijing 100029China Beijing Key Laboratory of Bioprocess Beijing University of Chemical TechnologyBeijing 10029China

Microbial lipid fermentation encompasses intricate complex cell growth processes and heavily relies on expert experience for optimal *** modeling of the fermentation process assists researchers in making intelligent decisions,employing logical reasoning and strategic planning to optimize lipid *** this study,the effects of medium components and concen-trations on lipid fermentation were investigated,*** then,leveraging the collated data,a variety of machine learning algorithms were used to model and optimize the lipid fermentation *** models,based on artificial neural networks and support vector machines,achieved R?values all higher than 0.93,ensuring accurate predictions of the fermentation *** linear regression was used to evaluate the respective target parameter,which were affected by the medium components of lipid ***,single and multi-objective optimiza-tion were conducted for lipid fermentation using the genetic *** results demonstrated the maximum biomass of 50.3 g·L^(-1) and maximum lipid concentration of 14.1 g:L^(-1) with the error between the experimental and predicted values less than 5%.The results of the multi-objective optimization reveal the synergistic and competitive relationship between biomass,lipid concentration,and conversion rate,which lay a basis for in-depth optimization and amplification.

关键词： microbial lipid machine learning artificial neural network support vector machine genetic algorithm

Tribological properties of PTFE-based fabric composites at cryogenic temperature

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Friction 2024年第2期12卷 245-257页

作者： Mingkun xu Zidan WANG lihe GUO Liming TAO Tianbao MA Tingmei WANG Qihua WANG Key Laboratory of Science and Technology on Wear and Protection of Materials Lanzhou Institute of Chemical PhysicsChinese Academy of SciencesLanzhou 730000China State Key Laboratory of Tribology Tsinghua UniversityBeijing 100084China Center of Materials Science and Optoelectronics Engineering University of Chinese Academy of SciencesBeijing 100049China

Fabric composites are widely employed in self-lubricating bearing liners as solid lubrication *** the tribological behaviors of fabric composites have been extensively studied,the cryogenic tribological properties and mechanisms have been scarcely reported and are largely unclear to instruct material design for aerospace and other high-tech ***,the tribological properties of polytetrafluoroethylene(PTFE)-based hybrid-fabric composites were investigated at cryogenic and ambient temperatures in the form of pin-on-disk friction under heavy *** results suggest that the friction coefficients of the hybrid-fabric composites obviously increase with a decrease in wear when the temperature drops from 25 to−150°***,thermoplastic polyetherimide(PEI),as an adhesive for fabric composites,has better cryogenic lubrication performance than thermosetting phenol formaldehyde(PF)resin,which can be attributed to the flexible chemical structure of *** excellent lubrication performance of hybrid-fabric composites is attributed to the transfer film formed by PTFE fibers on the surface of fabrics.

关键词： cryogenic temperatures fabric composites friction and wear transfer film

Effects of livestock and poultry breeding pollution on health risks:Evidence from a hog breeding case in rural China

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Chinese Journal of Population,Resources and Environment 2020年第4期18卷 342-349页

作者： Dan Fan Yanxin Mao lihe xu Wenguo Wang Western China Economic Research Center Southwestern University of Finance and EconomicsChengdu611130China National Survey Research Center Renmin University of ChinaBeijing100872China Guangdong Institute for International Strategies Guangdong University of Foreign StudiesGuangzhou510420China Biogas Institute of Ministry of Agriculture and Rural Affairs Chengdu610041China Key Laboratory of Development and Application of Rural Renewable Energy Ministry of Agriculture and Rural AffairsChengdu610041China

With the rapid development of livestock and poultry breeding industries,pollution problems caused by the discharge of wastewater and manure have become increasingly ***,studies on the impacts of this pollution on rural residents'health are *** on data from the Peking University's China Family Panel Studies in 2010 and 2014,this paper uses a cross-sectional and panel data probit model to estimate the probability of breeding industry development in rural areas increasing the health risks of local ***,the study found that the more households engaged in breeding in the region or the larger the scale of regional breeding,the higher the health risks to local villagers,particularly in areas where pigs are ***,compared with individual farming,the greater the proportion of large-scale farming,the higher the health risks to ***,the development of the breeding industry seldom includes the ecological recycling of wastes and fails to reduce the use of local pesticides and fertilizers,thereby increasing the health risks to ***,this paper argues that providing technology to process breeding industry waste and establish an organic industrial production chain will be crucial to reducing the impact of breeding industry pollution on human health.

关键词： Farming Pollution Health risk Rural areas

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中国抗疫的制度创新:对口援助

经济学（季刊） 2022年第5期22卷 1639-1658页

作者：徐丽鹤张晓波广东外语外贸大学广东国际战略研究院北京大学光华管理学院 100871

如何破解新冠肺炎疫情下医疗资源不足、降低疫情死亡率成了各国执政能力的大考。与部分发达国家相比,中国的对口援助制度创新是取得非凡防疫成绩的原因之一。其创新之处在于将纵向治理(中央—地方)向纵横交错(中央—地方—地方)模式转... 详细信息

如何破解新冠肺炎疫情下医疗资源不足、降低疫情死亡率成了各国执政能力的大考。与部分发达国家相比,中国的对口援助制度创新是取得非凡防疫成绩的原因之一。其创新之处在于将纵向治理(中央—地方)向纵横交错(中央—地方—地方)模式转变。实证发现,对口援助破解了灾区资源短缺和配置低效的难题,显著降低了感染病例的死亡人数。运行机理是引进竞争机制,调动援助方的积极性,以及分散信息决策机制以提高援助的效率和质量。

关键词：对口援助理论机制新冠肺炎

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以行为学理论试析运动场空间问题

体育科学 1991年第2期12卷 78-81,97页

作者：徐立和山东大学威海分校

体育运动竞争的焦点,从体育行为学的角度看,即是在某种特定的空间区域内进行的一种对有限的运动场空间的争夺。本文以人体行为学为理论依据,结合各项体育运动的特点,从运动场空间的争夺的角度,对运动场空间的划分、场空间竞争的类型、... 详细信息

体育运动竞争的焦点,从体育行为学的角度看,即是在某种特定的空间区域内进行的一种对有限的运动场空间的争夺。本文以人体行为学为理论依据,结合各项体育运动的特点,从运动场空间的争夺的角度,对运动场空间的划分、场空间竞争的类型、场空间观念的变化、不同层次的场空间需求与运动员的意义及“非人”观与空间竞争的关系等作了理论的梳理与解释。

关键词：空间区域运动员体育运动运动场空间问题对手空间竞争身体接触体育行为学空间需求

THE SYNTHESES OF DERIVATIVES OF CYCLIC NUCLEOTIDE

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Chemical Research in Chinese Universities 1986年第1期4卷 33-40页

作者： Zhang lihe,Ma Lingtai,xu Cheng,Dong Lingjiao,Hang Qi and Wang xu (Department of Pharmaceutical Sciences,Beijing Medical College,Beijing)

By using triphenyl phosphine/carbon tetrachloride as a condensing reagent,2'-tosyl c-AMP reacted with RR-NH to give nucleoside 3',5'-cyolic phosphoramidates in 28?5% *** of 2'-tosyl c-AMP can be carried out in acetonitrile with alkyl *** can be completed by using sodium napnthalide at-78℃ in *** stereoisomers of these compounds have been separated and the structures were identified by 1H NMR.31P NMR and MS.

关键词： DCC nm OH Ph THE SYNTHESES OF DERIVATIVES OF CYCLIC NUCLEOTIDE CS 一主 UV TLC CZ

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财富分层、社会资本与农户民间借贷的可得性

金融研究 2017年第2期 131-146页

作者：徐丽鹤袁燕西南财经大学国际商学院四川成都611130 西南财经大学经济与管理研究院四川成都610074

本文使用"中国家庭金融调查"2011和2013年两轮的微观数据,首次实证检验了财富分层对农户进入民间借贷市场的影响及其机制。研究发现,与穷人相比,相对比较富有的家庭更容易获得民间借款。产生该现象的原因在于穷人没有额外的资本用以扩... 详细信息

本文使用"中国家庭金融调查"2011和2013年两轮的微观数据,首次实证检验了财富分层对农户进入民间借贷市场的影响及其机制。研究发现,与穷人相比,相对比较富有的家庭更容易获得民间借款。产生该现象的原因在于穷人没有额外的资本用以扩展社会网络,进而降低了进入民间借贷市场的可能。由此推论,非正规信贷市场亦存在信贷约束问题,民间融资并不能缓解贫困农户融资难的困境。该结论在使用工具变量解决了内生性问题、采用多层阀值标准定义贫富后仍然稳健。

关键词：财富分层社会资本民间借贷中国家庭金融调查

信贷来源结构对中小企业多维度创新活动的影响

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财经研究 2020年第7期46卷 19-34页

作者：徐丽鹤李青广东外语外贸大学广东国际战略研究院广东广州510420

中小型民营企业逐渐成为创新的主力,但是正规与非正规金融市场的发展对企业创新的影响是否存在差异尚待进一步探索。文章基于2018年广东省企业调查数据,将企业融资渠道归为三类:正规信贷、非正规信贷和供应链信用融资,并对比分析了三者... 详细信息

中小型民营企业逐渐成为创新的主力,但是正规与非正规金融市场的发展对企业创新的影响是否存在差异尚待进一步探索。文章基于2018年广东省企业调查数据,将企业融资渠道归为三类:正规信贷、非正规信贷和供应链信用融资,并对比分析了三者对企业多维度创新的影响差异及其作用机制。研究发现:(1)对技术型创新而言,银行贷款的作用显著较高;对非技术型创新(商业模式或应对环境规制)而言,非正规金融的促进作用更显著。(2)供应链信用融资有利于企业进行单维度创新,正规与非正规融资则能够促进企业的多维度创新。(3)总体上,正规信贷对促进企业创新的作用略高于非正规融资渠道。进一步检验发现,正规金融通过增加企业研发投入促进创新,供应链融资通过缓解现金流约束间接为创新融资。该结果是在考虑了企业和企业家的异质性、采用多种衡量方式并使用工具变量估计后的稳健性结论。

关键词：正规与非正规金融创新活动中小企业企业调查

水稻中MPK5稳态失衡抑制拟禾本科根结线虫与水稻的亲和互作

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植物病理学报 2022年第1期52卷 86-96页

作者：牛永瑞许立鹤肖炎农肖立英肖雪琼王高峰华中农业大学植物科学技术学院湖北省植物病害监测与安全控制重点实验室武汉430070

拟禾本科根结线虫(Meloidogyne graminicola)为水稻的重要土传病原,可严重为害水稻。本研究旨在探究水稻中丝裂原活化蛋白激酶5(MPK5)稳态失衡对拟禾本科根结线虫与水稻亲和互作的影响,并初步探讨其机制。首先,通过线虫侵染试验发现,在... 详细信息

拟禾本科根结线虫(Meloidogyne graminicola)为水稻的重要土传病原,可严重为害水稻。本研究旨在探究水稻中丝裂原活化蛋白激酶5(MPK5)稳态失衡对拟禾本科根结线虫与水稻亲和互作的影响,并初步探讨其机制。首先,通过线虫侵染试验发现,在水稻中超表达和沉默MPK5引发的MPK5稳态失衡均可抑制拟禾本科根结线虫与水稻的亲和互作。qRT-PCR分析结果显示,与水稻野生型不同,在MPK5超表达和沉默水稻株系中MPK5均受拟禾本科根结线虫诱导表达。同时,拟禾本科根结线虫可抑制MPK5超表达株系中几丁质酶的表达,但诱导MPK5沉默株系中病程相关基因PR5与PR10的表达。上述试验结果表明,MPK5稳态失衡可导致MPK5响应拟禾本科根结线虫的侵染,且在MPK5超表达和沉默水稻株系中MPK5介导水稻产生拟禾本科根结线虫抗性的机制不同。

关键词：拟禾本科根结线虫水稻 MPK5稳态亲和互作