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991.
Zeng Weihua Zhong Xiaohong Xue Pengli . State Key Laboratory of Water Environment Simulation School of Environment Beijing Normal University Beijing China . China’s Academy of Environmental Planning State Environmental Protection Administration Beijing 《中国人口.资源与环境(英文版)》2008,6(3):63-72
Intergenerational conflict coordination is the fundamental requirement and core of sustainable development. In this paper, through the analysis of the future generations-oriented management mechanisms for intergenerational conflict, the idea of mechanisms and institution building for the coordination and management of intergenerational conflict is put forward. Furthermore, the future generations-oriented virtual negotiation support system (NSS) for intergenerational conflict is developed, built on the analysis of the process simulation of intergenerational wealth transfer, intergenerational equilibrium allocation of resources, and strategies for the mitigation and avoidance of intergenerational conflict, through the application of advanced IT technology. The virtual NSS for intergenerational conflict is helpful to the practical application of the sustainable development theory; on the other hand, it can be applied directly to the intergenerational equilibrium allocation of resources, national economic accounting, formulation of sustainable development strategies and other urgent national economic and social development issues. Finally, the sustainable development theory can be enriched and extended. Therefore, the development of the future generations-oriented virtual NSS for intergenerational conflict has certain theoretical and practical effects on the theory of sustainable development. 相似文献
992.
通过三维荧光平行因子分析(EEM-PARAFAC)和二维相关光谱(2DCOS)分析了富含木质纤维素类物料(果蔬废物和杂草废物)和富含木质素类物料(秸秆废物和园林修剪废物)堆肥形成的富里酸的结构和组成.结果显示,两类堆肥物料形成的富里酸结构差异显著.虽然两类物料的荧光组分含量及变化基本相似,但是特征官能团与其荧光组分的变化顺序却不同.富含木质纤维素类物料堆肥形成的富里酸中类酪氨酸和类色氨酸先于芳环形成,而富含木质素类物料堆肥形成的富里酸中芳环先于类酪氨酸和类色氨酸.并且,研究发现在堆肥高温期和腐熟期,富里酸的芳环含量在木质纤维类和木质类物料中分别增加了约10%和5%,脂肪族的含量分别下降了约10%和6%,说明堆肥过程中富里酸结构中脂肪族逐渐降解并伴随其芳香性逐渐增加;结构方程模型结果表明,类富里酸、脂肪族基团和羧基是富里酸中芳环形成的关键组分.本文研究结果可为明确堆肥过程中富里酸的形成提供理论基础. 相似文献
993.
Intrauterine growth restriction (IUGR) and preeclampsia (PE) are leading causes of perinatal and maternal morbidity and mortality. Many studies have found association between low levels of insulin-like growth factor binding protein (IGFBP) proteases in the first trimester maternal circulation and the risk of subsequent development of PE and/or IUGR. These results are generally interpreted to reflect decreased production of the proteases by the placenta, leading to reduced proteolysis of IGFBPs and lower free levels of insulin-like growth factor (IGF), resulting in diminished feto-placental development. However, the association between low circulating levels of placental proteins early in pregnancy and the subsequent development of IUGR and/or PE could be due to low exchange in the placenta and not due to reduced production. In contrast, late in pregnancy, the circulating levels of these proteins and their expression in the placenta are often elevated in PE, which may reflect upregulation to compensate for abnormal placental development, that is an adaptive mechanism to increase IGFBP proteolysis, increase local IGF levels and promote feto-placental growth. Further research into the biological mechanisms underlying these associations will aid the identification of high-risk pregnancies and the development of therapeutic targets for diseases for which there are presently no preventative measures. Copyright © 2010 John Wiley & Sons, Ltd. 相似文献
994.
生态破坏诱发中国水旱灾害程度及计量——以90年代为例 总被引:4,自引:1,他引:3
徐嵩龄 《中国人口.资源与环境》1999,9(4):46-51
生态破坏表现为植被破坏、水土流失、水系统淤塞,利用自然致灾因子和生态破坏因子可以构建水旱灾害的致灾函数。本文利用灾函数计算了生态破坏对中国90 年代水旱灾害的致灾影响度 相似文献
995.
996.
环境规制、要素禀赋与我国贸易模式的实证分析 总被引:3,自引:0,他引:3
傅京燕 《中国人口.资源与环境》2008,18(6)
当今的全球化趋势在导致贸易壁垒不断削减的同时,各国的环境规制却随之不断提升.本文使用世界银行的产业污染排放系统(IPPS)对我国制造业进行细分,运用显示性比较优势指数方法,把环境规制因素和要素禀赋因素同时引入到对贸易模式的分析.结果表明,贸易开放使我国的比较优势得以发挥,这表现为更多地专业化于清洁的劳动密集型产业,因此,即使总的污染排放有所增加,但单位产出的污染排放强度会有所下降.但另一方面,贸易开放使外资的流入增加,而资本累积是影响污染排放强度的主要因素,这必将导致我国的制造业结构更多地转向污染产业.因此,随着我国对外开放程度的加深,污染排放必呈上升态势.针对污染排放增加的原因,有效地利用产业政策和环境政策对实现资源环境的可持续发展是相当重要的. 相似文献
997.
998.
999.
Elizabeth L. White 《Journal of the American Water Resources Association》1976,12(2):351-370
ABSTRACT. The interrelationships between the runoff characteristics of watersheds (expressed as the mean annual flood), standard basin parameters (area, drainage properties, and relief), and the parameters which describe the solutional modification of the basins (carbonate rock fractions, sinkhole development, and measures of internal drainage) were used to group 62 carbonate watersheds. Simple binary correlations were obtained by direct plotting of the data. This was followed by multivariate analyses: factor and cluster analyses. Following the cluster analysis, which separated the basins into three groups, the variance within each group was examined again by binary correlations and by factor analysis. Prediction equations for those basins underlain by dolomite rock [QBAR = 12.4 TOT1.01] and for those basins underlain by carbonate rock with very little surface expression [QBAR = 43.5 TOT0.87] were proposed. Basins underlain by karstic limestone had a large amount of variance within the data set; therefore no prediction equation could be obtained. (QBAR = mean annual flood, cfs; TOT = total length of all blue lines shown on topographic maps, miles.) 相似文献
1000.