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471.
472.
张婷婷 《中国ISO14000认证》2012,(3):19-23
本文论述了PM2.5对环境的危害,在剖析PM2.5组成与来源的基础上,提出防控PM2.5的政策与技术方面的建议,以期为今后PM2.5的防控工作提供理论基础。 相似文献
473.
Assessing field vulnerability to phosphorus loss in Beijing agricultural area
using Revised Field Phosphorus Ranking Scheme 总被引:1,自引:0,他引:1
Guanting Reservoir,one of the drinking water supply sources of Beijing,suffers from water eutrophication.It is mainly supplied by Guishui River.Thus,to investigate the reasons of phosphorus(P)loss and improve the P management strategies in Guishui River watershed are important for the safety of drinking water in this region.In this study,a Revised Field P Ranking Scheme(PRS)was developed to reflect the field vulnerability of P loss at the field scale based on the Field PRS.In this new scheme,six factors are included, and each one was assigned a relative weight and a determination method.The affecting factors were classified into transport factors and source factors,and,the standards of environmental quality on surface water and soil erosion classification and degradation of the China were used in this scheme.By the new scheme,thirty-four fields in the Guishui River were categorized as"low","medium"or"high"potential for P loss into the runoff.The results showed that the P loss risks of orchard and vegetable fields were higher than that of corn and soybean fields.The source factors were the main factors to affect P loss from the study area.In the study area,controlling P input and improving P usage efficiency are critical to decrease P loss.Based on the results,it was suggested that more attention should be paid on the fields of vegetable and orchard since they have extremely high usage rate of P and high soil test of E Compared with P surplus by field measurements,the Revised Field PRS was more suitable for reflecting the characteristics of fields,and had higher potential capacity to identify critical source areas of P loss than PRS. 相似文献
474.
Integrated strategies to reduce vulnerability and advance adaptation,mitigation, and sustainable development 总被引:4,自引:1,他引:3
Indur M. Goklany 《Mitigation and Adaptation Strategies for Global Change》2007,12(5):755-786
Determinants of adaptive and mitigative capacities (e.g., availability of technological options, and access to economic resources,
social capital and human capital) largely overlap. Several factors underlying or related to these determinants are themselves
indicators of sustainable development (e.g., per capita income; and various public health, education and research indices).
Moreover, climate change could exacerbate existing climate-sensitive hurdles to sustainable development (e.g., hunger, malaria,
water shortage, coastal flooding and threats to biodiversity) faced specifically by many developing countries. Based on these
commonalities, the paper identifies integrated approaches to formulating strategies and measures to concurrently advance adaptation,
mitigation and sustainable development. These approaches range from broadly moving sustainable development forward (by developing
and/or nurturing institutions, policies and infrastructure to stimulate economic development, technological change, human
and social capital, and reducing specific barriers to sustainable development) to reducing vulnerabilities to urgent climate-sensitive
risks that hinder sustainable development and would worsen with climate change. The resulting sustainable economic development
would also help reduce birth rates, which could mitigate climate change and reduce the population exposed to climate change
and climate-sensitive risks, thereby reducing impacts, and the demand for adaptation. The paper also offers a portfolio of
pro-active strategies and measures consistent with the above approaches, including example measures that would simultaneously
reduce pressures on biodiversity, hunger, and carbon sinks. Finally it addresses some common misconceptions that could hamper
fuller integration of adaptation and mitigation, including the notions that adaptation may be unsuitable for natural systems,
and mitigation should necessarily have primacy over adaptation.
相似文献
Indur M. GoklanyEmail: |
475.
统计了洛阳分公司2006年度事故隐患情况,从未遂事件、事故隐患的时间段、后果、性质、直接原因等方面进行了深入细致的分析,找出影响洛阳分公司安全生产的主要隐患,提出了相应对策措施和建议. 相似文献
476.
477.
施工张拉控制是张弦网壳结构的关键技术之一,提出采用控制索原长的反分析方法追踪结构施工整个过程。首先,通过控制索在预应力状态下的张拉力求出零状态和索原长,并同时获得预应力态下所有单元的内力。在此基础上,通过控制每一级张拉索的原长,进行非线性有限元迭代计算,可求出索在分级分批施工时的控制力,并用VC++6.0编制相应的计算程序。这一方法有效地避免了通用有限元需要反复试算,计算繁琐的缺点。最后,以张弦网壳结构模型为试验对象,按分级分批张拉的方式模拟结构的现场施工,并跟踪施工过程中杆件单元的应力状态。结果表明,数值模拟计算与试验值吻合较好,计算结果可靠,该方法能精确模拟结构的施工成形过程,且在整个过程中,每根索只需张拉一次,简化了施工工艺。 相似文献
478.
479.
480.
The off-gas handling system is a vital component of a smelter and it is essential that it operates in accordance with environmental regulations. A key feature of the off-gas management system is maintaining a slightly negative system pressure to prevent gas leakage, such as SO2, out into the work and external environments. To enhance sustainable development, there is also growing interest in capturing and reusing the significant amount of heat and CO2 contained within off-gas. The potential incorporation of heat and CO2 recovery systems places importance on enhancing control to minimize the risk of both gas leakage and disturbance of the smelting process. With these requirements in mind, an easily implementable feedforward control enhancement to existing control schemes is proposed to help provide improved performance. 相似文献