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661.
研究了聚乙烯醇(PVA)加少量海藻酸钠及SiO2、CaCO3的方法固定高效菌处理PTA污水.结果表明,采用质量分数分别为PVA 10%、海藻酸钠0.3%、特种菌种10%、SiO2 3%、CaCO30.3%,用饱和硼酸溶液(pH为4.0)作为交联剂,制得的颗粒处理PTA废水时,废水COD负荷为2.91kg/m3·d时,CODcr、TOC、TA去除率均为85%以上;废水COD负荷为12.2kg/m3j·时,CODcr去除率仍为50%以上、TOC去除率为60%以上,当pTA废水pH从55降至35时,CODcr、TOC、TA去除率仍在86%以上. 相似文献
662.
- DOI: http://dx.doi.org/10.1065/espr2006.02.294
Background, Aim and Scope. To better address the requirements of the changing multilateral order, the United Nations Industrial
Development Organization (UNIDO) Cleaner Production Programme, in 2004, developed the new Sustainable Industrial Resource
Management (SIRM) approach. This approach is in accordance with the principles decided at the United Nations Conference on
Environment and Development (UNCED) in Rio de Janeiro, Brazil in 1992. Unlike the traditional approaches to environmental
management, the SIRM concept captures the idea of achieving sustainable industrial development through the implementation
of circular material and energy flows in the entire production chain and reduction of the amount of material and energy used
with greater efficiency solutions. The SIRM approach seeks to develop new models to encourage a shift from selling products
to supplying services, modifying, in this manner, the supplier/user relationship and resulting in a win-win situation for
the economy and the environment. Chemical Leasing represents such a new service-oriented business model and is currently being
promoted by UNIDO′s Cleaner Production Programme.
Main Features. One of the potential approaches to address the problems related to ineffective use and over-consumption of
chemicals is the development and implementation of Chemical Leasing business models. These provide concrete solutions to the
effective management of chemicals and on the ways negative releases to the environment can be reduced. The Chemical Leasing
approach is a strategy that addresses the obligations of the changing international chemicals policy by focusing on a more
service-oriented strategy. Mexico is one of the countries that were selected for the implementation of UNIDO's demonstration
project to promote Chemical Leasing models in the country. The target sector of this project is the chemical industry, which
is expected to shift their traditional business concept towards a more service and value-added approach. This is being achieved
through the development of company specific business models that implement the above-indicated Chemical Leasing concept with
the support from the Mexican National Cleaner Production Centre (NCPC).
Results and Conclusions. The implementation of Chemical Leasing in Mexico has proven to be an efficient instrument in enhancing
sustainable chemical management and significantly reducing emissions in Mexico. Several companies from the chemical industrial
sector implement or agreed to implement chemical leasing business models. Based on the positive findings of the project,
several Mexican companies started to negotiate contents of possible Chemical Leasing contracts with suitable business partners.
The project further aimed at disseminating information on Chemical Leasing. It successfully attracted globally operating companies
in the chemicals sector to explore possibilities to implement Chemical Leasing business models in Mexico. At the international
level, the results of the UNIDO project were presented on 20TH September 2005 during a side event of the Strategic Approach
to International Chemicals Management (SAICM) Preparation Conference in Vienna.
Recommendations and Outlook. To facilitate the promotion and application of Chemical Leasing project at international level,
UNIDO is currently developing a number of tools to standardize Chemical Leasing projects. These include, among others, Chemical
leasing contract models; Chemical Leasing data base to find partners for chemical leasing; and guidelines to implement Chemical
Leasing projects and work programmes. 相似文献
663.
Numerous empirical and simulation-based studies have documented or estimated variable impacts to the economic growth of nation states due to the adoption of domestic climate change mitigation policies. However, few studies have been able to empirically link projected changes in economic growth to the provision of public goods and services. In this research, we couple projected changes in economic growth to US states brought about by the adoption of a domestic climate change mitigation policy with a longitudinal panel dataset detailing the production of outdoor recreation opportunities on lands managed in the public interest. Joining empirical data and simulation-based estimates allow us to better understand how the adoption of a domestic climate change mitigation policy would affect the provision of public goods in the future. We first employ a technical efficiency model and metrics to provide decision makers with evidence of specific areas where operational efficiencies within the nation's state park systems can be improved. We then augment the empirical analysis with simulation-based changes in gross state product (GSP) to estimate changes to the states’ ability to provide outdoor recreation opportunities from 2014 to 2020; the results reveal substantial variability across states. Finally, we explore two potential solutions (increasing GSP or increasing technical efficiency) for addressing the negative impacts on the states’ park systems operating budgets brought about by the adoption of a domestic climate change mitigation policy; the analyses suggest increasing technical efficiency would be the most viable solution if/when the US adopts a greenhouse gas reduction policy. 相似文献
664.
运用Agilent(安捷伦)1200系列高效液相色谱和多环芳烃专用柱ZORBAX Eclipse PAH(4.6×250mm、5μm,P.N.959990-918,S.N.USPAB01066),对16种多环芳烃化合物混合溶液进行分析,根据具体实验条件优化EPA8310中色谱分离条件并得到了更节省时间、分离效率更好的流动相梯度变化程序。 相似文献
665.
Mediation support systems for facilitating resolution of natural resources conflicts must be able to systematically identify
and use a full complement of data and value sets relevant to the spectrum of issues underlying the conflict. A stepwise computer-supported
procedure for developing and then blending contrasting issue-sensitive stakeholder plans in map form for forest use is described
and demonstrated. The goal is a balanced plan that efficiently satisfies the more important land-use guidelines of each stakeholder
reasonably well. This procedure, SIRO-MED, can be applied at any level of detail compatible with available analytical resources
and to resources other than forests. 相似文献
666.
氧化镁法脱硫,具有工艺流程短、脱硫效率高等优点,对控制烟气SO2造成的大气污染是一种行之有效的办法,具有推广应用的广阔前景。 相似文献
667.
李同明 《中国环境管理干部学院学报》1999,(4)
本文主要论述了把效率与公平的统一纳入可持续发展之中的新观念。首先阐述了可持续发展的深刻内涵及思想本质,然后论述了可持续发展的公平观(当代人之间的公平及代际公平),以及可持续发展的效率现。用可持续发展及“三个效益”统一的指导思想和观点,综合论述了可持续发展和公平、效率的统一性。 相似文献
668.
本文以福建省龙海市为例,分析了龙海市农业发展优势与存在的问题,提出了建设海峡西岸高效持续农业示范区的基本思路与技术对策 相似文献
669.
Hassan Fathabadi 《International Journal of Green Energy》2020,17(12):742-755
ABSTRACT In this paper, a novel evacuated tube solar collector (ETSC) is first designed and built. Then, the impact of adding reflector, reflector plus single-axis sun tracker and reflector plus two-axis sun tracker to the built ETSC on the thermal efficiency of the ETSC is evaluated both theoretically and experimentally. In this regard, four identical versions of the proposed ETSC have been built and utilized in four collectors built and presented in this research work. The first collector is the same proposed built ETSC, the second collector is a parabolic trough solar collector comprising one built ETSC and a reflector (ETSC+R), the third collector is composed of one built ETSC, a reflector and a single-axis sun tracker all built in this study (ETSC+R+ ST), and the fourth collector consists of one built ETSC, a reflector and a two-axis sun tracker all built in this study (ETSC+R+ DT). Theoretical basis and concepts of the four collectors are formulated and analyzed in separate subsections. Theoretical results are outlined and highlighted at the end of each subsection. Experimental measurements and data obtained from the operation of the four collectors in the four seasons are presented that point by point verify theoretical results obtained in this study. To provide a comprehensive view, a techno-economic numerical comparison is performed between the four collectors. The following points, which are also the novelty and contributions of this work, are deduced from theoretical concepts, experimental data, and comparison provided in this study: ?There is no technical and economic justification for adding a reflector to an ETSC that results in forming a parabolic trough solar collector (ETSC+R) without any sun tracker. ?There is no economic justification for adding a single-axis sun tracker to a parabolic trough solar collector (ETSC+R). ?There is no economic justification for adding a two-axis sun tracker to a parabolic trough solar collector (ETSC+R). ?Comparing between a two-axis sun tracker and a single-axis sun tracker, adding the single-axis type to a parabolic trough solar collector (ETSC+R) is more advantageous. 相似文献
670.
Political pressures exist to increase the economic efficiency of timber management and production on the national forests
managed by the USDA Forest Service. There is growing belief both outside and within the Forest Service that current levels
of timber production, and most particularly uneconomic timber production, should be reduced. Many argue that eliminating uneconomic
timber management programs will both save money and reduce environmental degradation. This article traces the political evolution
of the focus on economic efficiency in timber production and explores the political-institutional factors that are shaping
the current policy debate. The below-cost issue is less about economic efficiency than it is about political advantage and
alternative political visions of the societal role of the nation's national forests now and in the future. 相似文献