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Rangeland Privatization and Its Impacts on the Zoige Wetlands on the Eastern Tibetan Plateau

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Journal of Mountain science 2005年第2期2卷 105-115页

作者： YAN Zhaoli WU Ning phd assistant professor from Chengdu Institute of Biology Chinese Academy of Sciences and a rangeland specialist at the International Center for Integrated Mountain Development （ICIMOD） phd supervisor professor and executive deputy director of Chengdu Institute of Biology Chinese Academy of Sciences

The high Zoige Basin （Ruoergai Plateau） on the eastern Tibetan Plateau is a fault depression formed during intensive uplifting of the Tibetan Plateau. The wetland is globally important in biodiversity and is composed of marshes, bogs, fens, wet meadows and shallow water interspersed with low hills and sub-alpine meadows. Most of the Zoige wetlands have long been one of the most important grazing lands in China. Recent rangeland policy has allowed grazing, and usable wetland areas have been being legally allocated to individuals or groups of households on a long-term lease basis. Privatizafion of the wetland has impacted the Zoige wetlands in aspects of hydrologic condition, landscape and biodiversity. The uneven spatial distribution of water resources onprivatelands has led to the practice of extracting ground water, which has decreased the perched water table in Zoige. Fencing off the rangelands and grazing on expanding sand dunes have affected landscapes. Variation in the water table has led to the changes in vegetation diversity, resulting in the changes in wildlife and aquatic diversities and ecosystem processes. Making use all year round of the pasture that was previously grazed only in summer has shrunk the daily activity space of wildlife, and the newly erected fences blocked the movement of wild animals looking for food in the snow to lower and open areas. To maintain the favorable conditions of the Zoige wetland ecosystem, the author suggests that, in addition to biophysical research and implementation of conservation practices, there is an immediate need to initiate an integrated management program, increase public awareness of wetland functions and provide better training for the local conservation staff.

关键词： Tibetan Plateau rangeland privatization Zoige (Ruoergai) wetland ecosystem integrity landscape biodiversity

Elimination of extraordinarily high cracking susceptibility of aluminum alloy fabricated by laser powder bed fusion

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Journal of Materials science & Technology 2022年第8期103卷 50-58页

作者： Holden Hyer Le Zhou Sharon Park Thinh Huynh Abhishek Mehta Saket Thapliyal Rajiv S.Mishra Yongho Sohn Department of Materials science and Engineering University of Central FloridaOrlandoFLUSA center for Friction Stir Processing Department of Materials Science and EngineeringAdvanced Materials and Manufacturing Processes InstituteUniversity of North TexasDentonTXUSA Now Research Scientist Oak Ridge National LaboratoryOak RidgeTNUSA Now Assistant professor Marquette UniversityMilwaukeeWIUSA Now phd Candidate Johns Hopkins UniversityBaltimoreMDUSA

Using the calculation of phase diagrams approach and Scheil solidification modeling,the Al-2.5Mg-1.0Ni-0.4Sc-0.1Zr alloy was designed,intentionally with an extraordinarily high cracking susceptibility,making it prime for solidification cracking during laser powder bed *** study demonstrates the ability to mitigate even the most extreme solidification cracking tendencies in aluminum alloys with only minor alloying additions of Sc and Zr,0.5 wt.%***,by employing a simple direct ageing heat treatment,good tensile mechanical properties were observed with a yield strength of 308 MPa,an ultimate tensile strength of 390 MPa,and a total elongation of 11%.

关键词： Additive manufacturing Cracking susceptibility Aluminum alloy CALPHAD Mechanical properties

Implementation of Teacher Training in China and Its Policy Implications

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China & World Economy 2016年第3期24卷 86-104页

作者： Hongyan Liu Chengfang Liu Fang Chang Prashant Loyalka phd candidate Center for Experimental Economics in Education Shaanxi Normal University China. Associate professor School of Advanced Agricultural Sciences Peking University China. Assistant professor Center for Experimental Economics in Education Shaanxi Normal University China. Associate professor Freeman Spogli Institute for International Studies Stanford University USA.

This study describes the current teacher training system in China, including the prevalence of teacher training, the types of training, training content and the ways that training is delivered. The paper presents subjective evaluations of training for principaIs and teachers using four diverse datasets. The results show that the National Teacher Training Project OVTTP） deviates from official policy objectives in several respects. The subjects of training programs and training content are not fully compliant with policy objectives. In addition, training opportunities are offered to a smaller proportion of rural teachers than urban teachers. It is found that the proportion of teachers and principals satisfied with the NTTP is lower than that for other types of training. Therefore, measures should be taken to increase training opportunities for rural teachers and to ensure the quality of training for all teachers.

关键词： China program implementation teacher training

To Board or Not to Board： Evidence from Nutrition, Health and Education Outcomes of students in Rural China

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China & World Economy 2016年第3期24卷 52-66页

作者： Aiqin Wang Alexis Medina Renfu Luo Yaojiang Shi Ai Yue phd candidate School of Economics and Management Northwest University China Research Fellow Freeman Spogli Institute for International Studies Stanford University USA Associate professor School of Advanced Agricultural Sciences Peking University China professor Center for Experimental Economics in Education Shaanxi Normal University China Associate professor Center for Experimental Economics in Education Shaanxi Normal University China

The debate over whether boarding school is beneficial for students still exists in both developing and developed countries. In rural China, as a result of a national school merger program that began in 2001, the number of boarding students has increased dramatically. Little research has been done, however, to measure how boarding status may be correlated with nutrition, health and educational outcomes. In this paper, we compare the outcomes of boarding to those of non-boarding students using a large, aggregate dataset that includes 59 rural counties across five provinces in China. We find that for all outcomes boarding students perform worse than non-boarding students. Despite these differences, the absolute levels of all outcomes are low for both boarding and non-boarding students, indicating a need for new policies that will target all rural students regardless of their boarding status.

关键词： boarding students education health nutrition rural China

How Off-farm Employment Affects Technical Efficiency of China＇s Farms＂ The Case of Jiangsu

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China & World Economy 2016年第3期24卷 37-51页

作者： Linxiu Zhang Weiliang Su Tor Eriksson Chengfang Liu professor Center for Chinese Agricultural Policy Institute of Geographic Sciences and Natural Resources Research Chinese Academy of Sciences China phd candidate Center for Chinese Agricultural Policy Institute of Geographic Sciences and Natm'al Resources Research Chinese Academy of Sciences Sino-Danish center for Education and Research University of Chinese Academy of Sciences China professor Department of Economics and Business Economics Aarhus University Denmark. Associate professor School of Advanced Agricultural Sciences Peking University China

Using three-wave survey data for four villages of Jiangsu Province in China, the present paper examines whether and to what extent off-farm employment affects the technical efficiency of agricultural production. The level of technical efficiency is measured using a stochastic frontier production function approach. Based on estimation results from instrumental variable panel quantile regressions we find that there is a positive significant effect of off-farm employment on the level of farm technical efficiency. We also find that fragmentation of farmland is a barrier to the improvement of technical efficiency. In addition, we find a downward trend in the level of agricultural technical efficiency among our sample. Therefore, the Chinese Government should stimulate agricultural mechanization and the development of farming techniques to improve technical efficiency in the context of increasing off-farm employment.

关键词： off-farm employment stochastic frontier analysis technical efficiency

Consumption Structure of Migrant Worker Families in China

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China & World Economy 2017年第4期25卷 1-21页

作者： Guangzhong Cao Kai Li Ruimin Wang Tao Liu Associate professor College of Urban and Environmental Sciences Center for Urban Future Research Key Laboratory for Land Planning and Development of the Ministry of Land and Resources Peking University China phd Candidate School of Public Administration and Policy Renmin University of China China phd Candidate Hanqing Advanced Institute of Economics and Finance Renmin University of China China Assistant professor College of Urban and Environmental Sciences Peking University China

This study draws on a survey of migrants in 12 cities across four major urbanizing areas in China and investigates the structure of migrant worker families＇urban and rural consumption. The results show that the structure of migrant worker families＇ consumption has been dominated by survival consumption. These families tend to live frugally in cities while engaging in conspicuous consumption in their rural hometowns. The structure of migrant worker families＇consumption is mainly shaped by their income stability and wealth levels rather than their current income level. Moreover, migrant worker families with high educational levels and those who intend to settle permanently in cities are likely to allocate substantial expenditure to status and hedonic consumption and to upgrade their urban consumption structure.

关键词： China complete urbanization consumption structure migrant worker

Effects of Parental Migration on Mental Health of Left-behind Children： Evidence from Northwestern China

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China & World Economy 2016年第3期24卷 105-122页

作者： Yaojiang Shi Yu Bai Yanni Shen, Kaleigh Kenny Scott Rozelle professor Center for Experimental Economics in Education Shaanxi Normal University China. phd candidate Center for Chinese Agricultural Policy Institute of Geographic Sciences and Natural Resources Research Chinese Academy of Sciences University of Chinese Academy of Sciences China. Graduate student Center for Experimental Economics in Education Shaanxi Normal University China. Research Assistant Freeman Spogli Institute for International Studies Stanford University USA. professor Freeman Spogli Institute for International Studies Stanford University USA.

China＇s rapid development and urbanization have induced large numbers of rural residents to migrate from their homes in the countryside to urban areas in search of higher wages. It is estimated that there are more than 60 million ＂left-behind children ＂＂（LBC） remaining in the countryside after their parents migrate, typically living with surrogate caregivers. Extensive research has focused on the impact of parental out- migration on children＇s mental health, but less attention has been paid to the effects of parental return-migration. The present paper examines the changes in mental health before and after the parents of fourth and fifih grade students out-migrate or return-migrate. We draw on a panel dataset collected by the authors of more than 19 000 students from 252 rural primary schools in northwestern China. Using DID and propensity score matching approaches, our results indicate that parental out-migration has a significant negative impact on the mental health of LBC, as they tend to exhibit higher levels of anxiety and lower levels of self-esteem. However, we find that parental return-migration has no significant effect on the mental health of LBC.

关键词： left-behind children mental health out-migration return-migration rural China

Renewable Biomass as a Platform for Preparing Green Chemistry

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Journal of Renewable Materials 2024年第2期12卷 325-328页

作者： Qiaoguang Li Puyou Jia Ying Luo Yue Liu College of Chemistry and Chemical Engineering Zhongkai University of Agriculture and EngineeringGuangzhou510225China Institute of Chemical Industry of Forestry Products Chinese Academy of ForestryNanjingChina College of Materials and Energy South China Agricultural UniversityGuangzhou510642China College of Chemical Engineering Qingdao University of Science and TechnologyQingdao266061China

1 About the Special Issue Editor Qiaoguang Li is an associate professor and master’s supervisor in the Department of College of Chemistry and Chemical Engineering,Zhongkai University of Agriculture and *** received his phd from Institute of Chemical Industry of Forestry Products,Chinese Academy of Forestry in *** has been focusing his research on the chemical basis and application of natural *** has published nearly 30 international peer reviewed papers and applied for 10 patents.

关键词： Biomass Platform patent

Communication With Folksonomy in technical libraries

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Communication With Folksonomy in technical libraries