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化肥污染对粮食作物生产的环境惩罚效应 被引量:65
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作者 陆文聪 刘聪 《中国环境科学》 EI CAS CSSCI CSCD 北大核心 2017年第5期1988-1994,共7页
利用非径向、非角度的SBM模型,在考虑环境非期望产出的基础上,测量了1998~2013年中国31个省区小麦、玉米和水稻3种主要粮食作物的环境效率,并在此基础上采用动态面板GMM方法实证检验了化肥污染对粮食作物环境效率的影响.结果显示:我国... 利用非径向、非角度的SBM模型,在考虑环境非期望产出的基础上,测量了1998~2013年中国31个省区小麦、玉米和水稻3种主要粮食作物的环境效率,并在此基础上采用动态面板GMM方法实证检验了化肥污染对粮食作物环境效率的影响.结果显示:我国粮食作物的环境效率呈现出波动中稳步上升的趋势,尤其2003年之后上升态势更加明显,粮食作物环境效率的整体水平较低,主产区粮食作物的环境效率高于主销区和产销平衡区的环境效率;化肥污染对粮食作物环境效率存在显著的负面影响,化肥污染量每增加1%,小麦、玉米和水稻的环境效率分别下降10.38%、13.45%和13.19%,这表明化肥污染对粮食生产过程存在显著"环境惩罚"效应. 展开更多
关键词 环境惩罚 化肥污染 环境效率 SBM模型 动态面板GMM
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Bi_(5)O_(7)I/g-C_(3)N_(4)Z型异质结的常温沉淀制备及其光催化性能研究 被引量:8
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作者 李冬梅 卢文聪 +4 位作者 梁奕聪 王逸之 陈海强 李俊添 谢震宇 《中国环境科学》 EI CAS CSCD 北大核心 2021年第9期4120-4126,共7页
以Bi(NO3)3·5H2O、KI和g-C_(3)N_(4)为前驱体,采用常温沉淀法制备Bi_(5)O_(7)I/g-C_(3)N_(4)Z型异质结复合光催化剂,表征其光吸收性能、微观形貌、光生电子-空穴的分离效率等特性,研究新型光催化剂对RhB的可见光催化降解性能,探讨其... 以Bi(NO3)3·5H2O、KI和g-C_(3)N_(4)为前驱体,采用常温沉淀法制备Bi_(5)O_(7)I/g-C_(3)N_(4)Z型异质结复合光催化剂,表征其光吸收性能、微观形貌、光生电子-空穴的分离效率等特性,研究新型光催化剂对RhB的可见光催化降解性能,探讨其可见光催化过程活性基团种类以及作用机理.结果表明:利用沉淀法合成Bi_(5)O_(7)I/g-C_(3)N_(4)的条件为:Bi(NO_(3))_(3)·5H_(2)O、KI和g-C_(3)N_(4)的投加量分别为4.85g、1.66g和1.61g,乙二醇的用量为50mL,反应液的pH值为12,反应搅拌速度为200r/min,反应温度为25℃.Bi_(5)O_(7)I/g-C_(3)N_(4)异质结无杂相生成且纯度高,异质结复合发生在g-C_(3)N_(4)的(002)晶面和Bi_(5)O_(7)I的(203)晶面,但g-C_(3)N_(4)和Bi_(5)O_(7)I的化学结构未受影响.Bi_(5)O_(7)I/g-C_(3)N_(4)呈三维纳米花瓣形貌结构,为光生电子-空穴的迁移提供了大量的接触位点.Bi_(5)O_(7)I的g-C_(3)N_(4)掺杂改性使其光催化活性显著增强,其光吸收边缘由425nm红移至462nm,Bi_(5)O_(7)I/g-C_(3)N_(4)的能带排列结构与Z型异质结匹配,促进了光生电子-空穴的分离.其光电流密度(11.5mA/cm)约为g-C_(3)N_(4)和Bi_(5)O_(7)I对应值的2.66倍和1.47倍.Bi_(5)O_(7)I/g-C_(3)N_(4)对罗丹明B的可见光催化降解率为93.9%,显著高于g-C_(3)N_(4)(58%)和Bi_(5)O_(7)I(49.7%)的降解效果,其光催化氧化活性主要来自羟基基团、超氧基团和光生空穴等中间态自由基. 展开更多
关键词 常温沉淀法 Bi_(5)O_(7)I/g-C_(3)N_(4) Z型异质结 可见光催化性能
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Technological Options to Ameliorate Waste Treatment of Intensive Pig Production in China:An Analysis Based on Bio-Economic Model 被引量:5
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作者 lu wen-cong MA Yong-xi Holger Bergmann 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2014年第2期443-454,共12页
Ameliorating waste treatment by technological improvements affects the economic and the ecological-environment benefits of intensive pig production. The objective of the research was to develop and test a method to de... Ameliorating waste treatment by technological improvements affects the economic and the ecological-environment benefits of intensive pig production. The objective of the research was to develop and test a method to determine the technical optimization to ameliorate waste treatment methods and gain insight into the relationship between technological options and the economic and ecological effects. We developed an integrated bio-economic model which incorporates the farming production and waste disposal systems to simulate the impact of technological improvements in pig manure treatment on economic and environmental benefits for the case of a pilot farm in Beijing, China. Based on different waste treatment technology options, three scenarios are applied for the simulation analysis of the model. The simulation results reveal that the economic-environmental benefits of the livestock farm could be improved by reducing the cropland manure application and increasing the composting production with the current technologies. Nevertheless, the technical efficiency, the waste treatment capacity and the economic benefits could be further improved by the introduction of new technologies. It implies that technological and economic support policies should be implemented comprehensively on waste disposal and resource utilization to promote sustainable development in intensive livestock production in China. 展开更多
关键词 technological options waste treatment pig production bio-economic model economic-environmental effects
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Modeling the effects of urbanization on grain production and consumption in China 被引量:3
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作者 lu wen-cong Chen Ning-lu Qian Wen-xin 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2017年第6期1393-1405,共13页
The impact of rapid urbanization on food security of China has received considerable attention.It is not clear whether China can strike a balance between urbanization and food security,especially grain security.There ... The impact of rapid urbanization on food security of China has received considerable attention.It is not clear whether China can strike a balance between urbanization and food security,especially grain security.There have been numerous studies examining the effects of urbanization on grain production or consumption,but few studies have yet analyzed grain balances.Based on the Chinese World Agricultural Regional Market Equilibrium Model(CWARMEM),this paper explores the impacts of urbanization on national and regional grain balances through different scenarios.The CWARMEM is a global partial equilibrium multimarket model which captures the differences between urban and rural residents as well as the effects of globalization.The results show that urbanization has a small negative effect on maintaining grain self-sufficiency.Despite of that,China is able to achieve the objective of grain security set by its policymakers.Moreover,urbanization changes regional grain balances across China:The position of Northeast China and North China,as two dominant grain suppliers of China,will be weaken;Central China and East China will increase dependence on other grain suppliers;the grain surplus of Northwest China will increase slightly.Besides,in terms of grain category,urbanization helps China achieve self-sufficiency in food grain(rice and wheat),while expands deficit of feed grain(maize). 展开更多
关键词 URBANIZATION grain self-sufficiency grain security
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