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31.
32.
对生态补偿政策的几点思考 总被引:5,自引:0,他引:5
李克国 《中国环境管理干部学院学报》2007,17(1):19-22
建立生态补偿政策是实现“三个转变”和制度创新的需要。环境资源价值理论、经济外部性理论和公共产品理论是生态补偿政策的理论基础;“破坏者付费,保护者受益原则”、“受益者补偿原则”、“公平性原则”、“政府主导、市场推进原则”和“分步推进”是生态补偿的基本原则。目前,我国事实的生态补偿政策主要包括财政补偿、流域内部补偿、征收生态环境补偿税费、市场方式补偿、异地开发补偿和国家间补偿。中国的生态补偿政策存在观念障碍、法律障碍、技术障碍,需要采取有效措施,尽快完善我国的生态补偿政策。 相似文献
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该文叙述了离心式机械振动台的工作原理,提出了计算思路和方法;推导了其计算公式;并根据工程的实际情况,把复杂的计算公式,简化成代数运算式。 相似文献
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于2015-2018年冬季(12月-2月)对广东省某医疗废物焚烧厂排放烟气及焚烧设施周边2.5 km范围内6个采样点分别进行了4次烟气和环境空气样品采集,应用高分辨气相色谱/高分辨质谱(HRGC-HRMS)联用技术对二(口恶)英(PCDD/Fs)浓度水平进行监测并对其组成特征进行了分析,运用主成分分析法(PCA)对周边环境空气中二(口恶)英来源进行了初步解析,同时采用VLIER-HUMAAN模型评估其对人体的健康风险.结果表明该医疗废物焚烧厂烟气二(口恶)英毒性当量浓度为0.542~21.300 ng·Nm-3(以I-TEQ计),排放水平较高;周边环境空气中PCDD/Fs质量浓度和毒性当量浓度变化范围分别为0.682~196.000 pg·m-3和0.036~17.700 pg·m-3(以I-TEQ计),周边环境空气中PCDD/Fs浓度明显受到排放源烟气落地点的影响.空气样品中二(口恶)英同族体及异构体分布指纹谱图与该焚烧设施排放烟气类似,空气质量浓度主要贡献单体以OCDD、1,2,3,4,6,7,8-HpCDF、OCDF以及1,2,3,4,6,7,8-HpCDD为主,主要毒性贡献单体为2,3,4,7,8-PeCDF.PCA源解析结论与指纹谱图特征分析结论基本一致,该研究区域中环境空气二(口恶)英主要来源于医疗废物焚烧烟气排放.健康风险评估结果表明,该区域人群呼吸暴露风险总体处于较为安全的水平(0.0032~0.141 pg TEQ·kg-1·d-1),部分个体的呼吸暴露贡献率超过了评价限值,应引起重视. 相似文献
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鄂尔多斯周缘地震带中长期地震趋势估计 总被引:2,自引:0,他引:2
本文基于一定的地震资料,分别应用最大熵原理、贝努里概型以及计算地震复发周期的经验关系式,对鄂尔多斯周缘地震带进行了中强地震的中长期地震趋势估计。 相似文献
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This paper argues that the environmental changes witnessed in the past decade call for a new approach to environmental management; an approach based not on the principle of the assimilative capacity of the environment but on the precautionary principle, and the emerging preventive environmental paradigm. Uncertainties in scientific knowledge and complexities in ecological systems have presented specific failures of the assimilative capacity methodology. It is argued that these failures are not circumstantial in nature, nor are they the result of misapplication of science by scientists. Rather, they represent inherent problems in the use of the assimilative capacity concept in environmental management. The emergence of the precautionary principle is discussed and a formulation of the principle is presented. In conjunction with the operational approach of clean production, we believe that this principle offers a sounder basis for the prevention of marine pollution in the next decade. 相似文献
39.
Cosmological implications of the Machian principle 总被引:1,自引:1,他引:0
The famous idea of Ernst Mach concerning the non-absolute but relational character of particle inertia is taken up in this paper and is reinvestigated with respect to its cosmological implications. From Thirring’s general relativistic study of the old Newtonian problem of the relativity of rotations in different reference systems, it appears that the equivalence principle with respect to rotating reference systems, if at all, can only be extended to the system of the whole universe, if the mass of the universe scales with the effective radius or extent of the universe. A reanalysis of Thirring’s derivations still reveals this astonishing result, and thus the general question must be posed: how serious this result has to be taken with respect to cosmological implications. As we will show, the equivalence principle is, in fact, fulfilled by a universe with vanishing curvature, i.e. with a curvature parameter, which just has the critical density , where is the Hubble constant. It turns out, however, that this principle can only permanently be fulfilled in an evolving cosmos, if the cosmic mass density, different from its conventional behaviour, varies with the reciprocal of the squared cosmic scale. This, in fact, would automatically be realized, if the mass of each cosmic particle scales with the scale of the universe. The latter fact, on one hand, is a field-theoretical request from a general relativistic field theory which fulfills H. Weyl’s requirement of a conformal scale invariance. On the other hand, it can perhaps also be concluded on purely physical grounds, when taking into account that as source of the cosmic metrics only an effective mass density can be taken. This mass density represents the bare mass density reduced by its mass equivalent of gravitational self-binding energy. Some interesting cosmological conclusions connected with this fact are pointed out in this paper. 相似文献
40.
Løkke S 《Environmental science and pollution research international》2006,13(5):342-349