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农村劳动力转移与土地流转不一致的影响因素分析——基于1986—2010年中国农村固定观察点数据

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财贸研究 2013年第5期24卷 32-38页

作者：陈浩陈中伟中南财经政法大学经济学院湖北武汉430073

通过对劳动力转移与土地流转影响因素的规范分析,并利用1986—2010年中国农村固定观察点数据进行验证,结果显示:中国农村劳动力转移与土地流转具有不一致性;家庭承包土地经营模式下农业劳动效率的提高是造成二者不一致的重要原因;提高... 详细信息

通过对劳动力转移与土地流转影响因素的规范分析,并利用1986—2010年中国农村固定观察点数据进行验证,结果显示:中国农村劳动力转移与土地流转具有不一致性;家庭承包土地经营模式下农业劳动效率的提高是造成二者不一致的重要原因;提高农村劳动力城市就业收入水平及其稳定性有利于二者趋同;较低的地租、较高的城市生活成本和城乡二元制度的约束制约了二者一致进行。为此,根据城乡统筹发展和城市化发展的要求提出相应的政策建议。

关键词：劳动力转移土地流转城乡统筹

Reviving Low-Temperature Performance of Lithium Batteries by Emerging Electrolyte Systems

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Renewables 2023年第1期1卷 2-20页

作者： Tingzhou Yang Yun Zheng Yizhou Liu Dan Luo Aiping Yu zhongwei chen Department of Chemical Engineering Waterloo Institute for NanotechnologyUniversity of WaterlooWaterlooOntario N2L 3G1 School of Information and Optoelectronic Science and Engineering South China Normal UniversityGuangdong 510006

Although lithium batteries have been successfully commercialized in the past two decades,they are particularly sensitive to ultralow *** most batteries,capacities and powers are lost at sub-zero temperatures,mainly due to the increased electrolyte viscosity,insufficient ionic conduction,slow charge-transfer kinetics,and reduced ion diffusing *** this review,we sorted out the critical factors leading to the poor low-temperature performance of electrolytes,and the comprehensive research progress of emerging electrolyte systems for the ultra-low temperature lithium battery is classified and *** further provide a systematic summary of the advanced characterization and computational simulation for low-temperature electrolyte systems to guide researchers in screening the low-temperature electrolytes,monitoring solvation/desolvation behavior,and investigating reaction *** their fundamental significance,our review might also forge a new opportunity and prospects in the effective design of electrolytes for the ultralow temperature application of energy storage devices.

关键词： lithium-ion battery low temperature emerging electrolyte systems advanced characterization solvation behavior

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公共意识对公共存在的维护和建构

哲学研究 2018年第6期 9-16,128页

作者：陈忠炜郭湛海军航空大学航空基础学院中国人民大学哲学院

公共意识由公共存在决定,又能动反作用于公共存在。这种机制,首先在于使主体认识和把握社会公共存在的本性,进而引领主体通过建构更优化的公共存在的实践,体现其能动和创造的特质。公共存在的层级和样态不同,相应的公共意识的作用方式... 详细信息

公共意识由公共存在决定,又能动反作用于公共存在。这种机制,首先在于使主体认识和把握社会公共存在的本性,进而引领主体通过建构更优化的公共存在的实践,体现其能动和创造的特质。公共存在的层级和样态不同,相应的公共意识的作用方式也不同。在个体群体层面,公共意识使主体确立公共的价值追求和评价体系;在社会国家层面,公共意识引领主体建构秩序规范和维护公共利益;在人类整体层面,公共意识通过凝聚历史合力促进人类命运共同体发展。人类社会作为公共存在的历史进步,需要公共意识发挥对其维护和建构的功能。

关键词：公共意识公共存在群体国家共同体

农民职业分化、经营规模与农地生产效率——基于县域数据的验证

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河北经贸大学学报 2020年第4期41卷 72-79页

作者：陈中伟郑州航空工业管理学院经济学院河南郑州450046

由全国第三次农业普查数据可知,随着农民职业分化导致劳均农地经营规模增加,但我国仍以小农户兼业经营农地为主,经营方式仍以传统经营为主。利用县域数据验证农民职业分化、农地经营规模对农地生产效率的影响,得到以下结论:农民职业分... 详细信息

由全国第三次农业普查数据可知,随着农民职业分化导致劳均农地经营规模增加,但我国仍以小农户兼业经营农地为主,经营方式仍以传统经营为主。利用县域数据验证农民职业分化、农地经营规模对农地生产效率的影响,得到以下结论:农民职业分化的广度对农地全要素生产率的影响呈“U”型,当前非农比例增加有利于农地全要素生产率的提高;农民职业分化的深度与农地全要素生产率、亩均产出和劳均产出均呈负相关,农民家庭非农收入比重越高农地经营越被忽视;劳均农地经营规模增加,有利于农地全要素生产率和劳均产出水平提高,但不利于亩均产出水平提高。加之考虑平原、山地、丘陵等农地异质性,进而得出相比平原地区,山区、丘陵地区农民职业分化深度(兼业程度)对亩均产出、劳均产出的负作用更大;山地、丘陵地貌下农地经营规模扩大造成亩均产出水平降低的作用更明显,导致劳均产出水平提高程度低于平原地区。

关键词：农民职业分化农地全要素生产率农地经营规模

新型城镇化背景下农村人口、资源与环境困境分析

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生态经济 2016年第11期32卷 92-97页

作者：陈中伟郑州航空工业管理学院河南郑州450015

基于新型城镇化的要求分析了我国人口、资源与环境困境现状,主要体现为农民农业收入增长受阻、农地资源利用效率低下和农村环境恶化。利用新古典经济学分析框架和发展经济学人口转移理论分析了困境产生的原因,是农村人多地少和收入消费... 详细信息

基于新型城镇化的要求分析了我国人口、资源与环境困境现状,主要体现为农民农业收入增长受阻、农地资源利用效率低下和农村环境恶化。利用新古典经济学分析框架和发展经济学人口转移理论分析了困境产生的原因,是农村人多地少和收入消费异地化导致的结果。走出困境的关键是推动农地流转、人口城镇化和完善农村基础设施,其中最关键的途径是推动农地流转和实现农业适度规模经营。文章设计了推动农地流转的方案,并有针对性地提出了完善相关制度的政策建议。

关键词：新型城镇化人口、资源与环境农村发展

Study on the Technological Conditions of Ultrasound-assisted Extraction of Polysaccharides from Ajuga ciliata Bunge (Fujian)

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Medicinal Plant 2021年第1期12卷 51-55页

作者： Wenwen LU Ruonan HE zhongwei chen Chao YI Zhuangyu ZHANG Yanyan ZHENG Xiamen Key Laboratory of Marine Medical Natural Products Resources Xiamen Medical CollegeXiamen 361000China

[Objectives]To determine the optimum technological conditions of ultrasound-assisted extraction of polysaccharides from Ajuga ciliata Bunge.[Methods]In this study,Ajuga ciliata Bunge was used as raw material,and an orthogonal experiment was designed based on the single factor experiment to investigate the effects of ultrasonic time,solid-liquid ratio,ultrasonic temperature and ultrasonic power on the extraction rate of polysaccharides from *** Bunge(Fujian).Range analysis,variance analysis and SSR test of significant differences between groups were carried out with SPSS 20.0,and the test results were verified.[Results]Under the conditions of ultrasonic temperature of 85℃,ultrasonic time of 80 min,solid-liquid ratio of 1∶15 g/mL and ultrasonic power of 500 W,the yield of polysaccharides from *** Bunge(Fujian)was the best.[Conclusions]This study can provide theoretical basis for the application of *** Bunge(Fujian).

关键词： Ajuga ciliata Bunge Polysaccharide Ultrasonic extraction Orthogonal test

Optimization of Extraction Process of Quercetin from Flos Sophorae Immaturus Using Orthogonal Design

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Medicinal Plant 2020年第6期11卷 67-71页

作者： Yanyan ZHENG Ruonan HE zhongwei chen Chao YI Wenwen LU Zhuangyu ZHANG Xiamen Key Laboratory of Marine Medicinal Natural Products and Cell Engineering/Xiamen Medical College Xiamen 361023 China

[Objectives]This study aimed to optimize the ultrasonic-assisted extraction process of quercetin from Flos Sophorae Immaturus.[Methods]The natural product quercetin in Flos Sophorae Immaturus was extracted by ultrasonic-assisted method,and the content of quercetin in the extract was determined by ultraviolet *** effect of ethanol concentration,solid/liquid ratio,temperature,time and ultrasonic power on the yield of quercetin in Flos Sophorae Immaturus was investigated by using single-factor *** on the results of single-factor experiments,an orthogonal experiment was designed to optimize the extraction *** experimental data obtained were subjected to range analysis,analysis of variance and SSR test using SPSS 20.0 software to obtain the optimal extraction *** results concluded were verified.[Results]The optimal ultrasonic-assisted extraction process for quercetin in Flos Sophorae Immaturus was as follows:temperature of 85℃,time of 30 min,solid/liquid ratio of 1∶20 g/mL,ethanol concentration of 50%.Under the optimal extraction conditions,the yield of quercetin in Flos Sophorae Immaturus was the highest.[Conclusions]This study provides a theoretical basis for the application of quercetin in Flos Sophorae Immaturus.

关键词： Flos Sophorae Immaturus Quercetin Ultrasonic-assisted extraction Orthogonal design

Optimization of Conditions for Extracting Luteolin from Ternate Grape Fern Herb by an Orthogonal Experiment

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Agricultural Biotechnology 2021年第1期10卷 99-102,108页

作者： Chao YI Qihuang LIN zhongwei chen Wenwen LU Yanyan ZHENG Zhuangyu ZHANG Xiamen Key Laboratory of Marine Medicinal Natural Products Resources Xiamen Medical CollegeXiamen 361000China

[Objectives] This study was conducted to optimize the extraction process of luteolin, a natural product of Ternate Grape Fern Herb, so as to provide a theoretical research basis for the chemical composition, pharmacological research and preparation development of Ternate Grape Fern Herb. [Methods] The effects of four factors including ultrasonic extraction time, liquid-to-material ratio, ultrasonic extraction temperature and ethanol concentration on extraction yield of luteolin from Ternate Grape Fern Herb were investigated by the ultrasonic-assisted extraction technology, through a single-factor experiment and an orthogonal experiment based on the single-factor experiment, and the experimental data was subjected to variance analysis and SSR analysis of the significance of differences between groups by SPSS20.0 software to select the optimal extraction process conditions. [Results] The optimal extraction process conditions were as follows: ultrasonic extraction time 25 min, liquid-to-material ratio 25∶1 ml/g, ethanol volume fraction 60%, ultrasonic extraction temperature 85 ℃. [Conclusions] The results were verified, and it was determined that the ultrasonic-assisted extraction process established in this study is reasonable and reliable, and can be used for the extraction of luteolin.

关键词： Ternate Grape Fern Herb Luteolin Ultrasonic-assisted extraction Orthogonal experiment

Exploration and Practice on the Construction Mode of Biopharmaceutical Training Base in Application-based Colleges and Universities

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Medicinal Plant 2021年第2期12卷 102-105页

作者： zhongwei chen Hebin LI Ying ZENG Qihuang LIN Ruonan HE Xuan HONG Xiamen Medical College Xiamen 361023 China

By using the methods of literature analysis,field investigation,exploration and research,experience summary,comparative inductive analysis,etc.,through the search of the latest literature and policy materials,production enterprises and domestic application-based undergraduate universities with related majors have been investigated on the *** analyzing the failed cases and drawing lessons from the successful experience,this paper explores the transformation and practical construction of the biopharmaceutical training base in application-based colleges and *** paper innovates and designs a new construction mode of biopharmaceutical training base in application-based universities,which provides reliable experience and valuable research results for the construction or transformation of biopharmaceutical training base in application-based colleges and *** has a very important potential value for promoting the social and economic benefits.

关键词： Biopharmaceutical Training base Construction mode Reform and innovation Exploration and practice