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991.
生物质能发展现状及前景分析 总被引:6,自引:0,他引:6
生物质能源作为惟一可再生、可替代化石能源转化成气态、液态和固态燃料以及其它化工原料或者产品的碳资源,随着化石能源的枯竭和人类对全球性环境问题的关注,其替代化石能源利用的研究和开发,已成为科学研究和社会关注的热点。本文对生物质能的资源分类和利用方式进行了分析和研究,提出了生物质能在中国的发展现状、存在的瓶颈以及前景和方向。 相似文献
992.
Joanna Endter‐Wada Judith Kurtzman Sean P. Keenan Roger K. Kjelgren Christopher M.U. Neale 《Journal of the American Water Resources Association》2008,44(4):902-920
Abstract: Landscape water conservation is an important issue for municipalities throughout the Western United States, and especially in Utah as rapid growth strains existing water supplies. We conducted interdisciplinary research in Layton, Utah, that aimed at understanding patterns of landscape water use among households and businesses. The research project involved three basic tasks. First, a landscape “water budget” was developed by producing a calibrated and classified mosaic of landscape type and area from airborne multispectral digital imagery, integrating this information with Layton City parcel boundary data to determine landscape vegetated areas per lot, and estimating irrigation needs derived from reference evapotranspiration (ETo) obtained using weather data for the Salt Lake City metropolitan region. Second, utilizing Layton water billing data, water use for each household and business was identified and categorized as “conserving,”“acceptable” or “wasteful” by determining how much the water applied varied from actual landscape plant need. Third, surveys were administered to a random stratified sample of households and businesses in the study area to investigate various factors that were hypothesized to be predictive of wasteful watering practices. This paper primarily focuses on analysis of the household and business survey data, which explores factors affecting urban landscape water use from a human behavioral perspective. We found that the most significant factors predicting actual water use were the type of irrigation system and whether the location was a household or business. Attitudinal and motivational characteristics were not consistently associated with water use. We found that wasteful watering is the result of many factors embedded in the complex context of urban landscapes. This implies that water conservation programs should identify potential wasteful users through analyses of water billing data and direct water conservation measures at these users by focusing on site‐specific evaluations and recommendations. Water audits or water checks are one such tool that some communities have employed to help people understand and assess the quantity of water needed by and applied to their landscapes. This approach provides an opportunity to evaluate situational constraints at particular locations and design appropriate strategies for reducing water waste. 相似文献
993.
Zhou Nianli 《中国人口.资源与环境(英文版)》2008,6(4):20-27
With the effect of the human trade doctrine in the international trade field, almost all the countries have paid more attention to the sustainable development of international trade. This article chose the export sustainable development as the research object. On the basis of the analysis of the theoretical connotation of the export sustainable development, this article tried to establish an evaluation indices system and set up an evaluation model of the export sustainable development level, and finally made some empirical research on China. The result indicates that the comprehensive level of the export sustainable development in China showed a tendency to rise from 1985 to 2003 and the export sustainable development level of China in these years can be divided into four grades: excellent, good, moderate and poor. In most years, the social economic benefits of export was obtained at the cost of the deterioration of environment and the depletion of resources, and the economic profit of export did not increase with the enlargement of the export scale because of the deterioration of the terms of trade. Therefore, China should be careful about the problem of poverty accompanied by the increase of export. 相似文献
994.
环境中主要持久性有机污染物检测技术研究进展 总被引:1,自引:0,他引:1
赵丽娟 《辽宁城乡环境科技》2013,(6):60-61,64
论述了持久性有机污染物的检测技术现状,包括环境标准、检测方法等,提出了我国在此领域存在的问题和发展方向。 相似文献
995.
柴玉香 《安全.健康和环境》2020,(3):50-52
分析了石化销售企业施工现场安全管理的现状以及产生的原因,针对上述问题提出了加强工程施工安全监管的建议和相关管理措施。 相似文献
996.
Transdisciplinary approaches are becoming increasingly adopted as a way to research complex socio-environmental problems. Conceptually, transdisciplinarity aims to foster meaningful knowledge co-production through integrative and participatory processes that bring together diverse actors, disciplines, and knowledge bases. In practice, transdisciplinarity is more ambiguous. While there is a growing body of literature on such approaches, there remains no widely-accepted definition, concrete framework, or empirical strategy for how to carry out a transdisciplinary project. We propose that this lack of explicit structure and entrenched meaning leaves space for transdisciplinary approaches to be shaped by the evolving network of participating scientists and stakeholders, according to their perspectives of the approach and what it embodies. Here, we examine the perspectives of a diverse group of actors (n = 42) embarking on a 10-year transdisciplinary research project focused on building resilience to natural hazards and disasters in New Zealand. We present the findings of qualitative surveys and group interviews that investigate stakeholders’ and scientists’ early perspectives of transdisciplinary, or co-created, research. The study represents the first stage of longitudinal research that will continue over the course of the project. Results show that early actors in the project share an overall consistent understanding of co-created research. Participants described a process that integrated diverse people and knowledge; created benefits on both a social and personal level; fostered clear, two-way dialogue; and overcame pragmatic and intrinsic challenges. Collectively, participants agreed with adopting transdisciplinary approaches to natural hazard, risk, and resilience research, with stakeholders showing a stronger degree of agreement than scientists. While attitudes towards transdisciplinarity were overall positive, a number of underlying conflicts emerged in regards to carrying out new modes of knowledge production within traditional social and institutional structures. These conflicts result in a tension that is felt by actors involved in transdisciplinary projects early on, and in some cases, influences perception of their ability to fully participate in such an approach. Evaluating actor perspectives and expectations early in the transdisciplinary process can give insight into how attitudes, expectations, and conflicts might shape transdisciplinary efforts, and can provide relevant parameters for assessing change over time. 相似文献
997.
高效离子色谱法检测F- 、CH3 COO- 、HCOO- 、Cl - 的方法研究 总被引:2,自引:0,他引:2
代希林 《环境监测管理与技术》2000,12(5):19-21
在对离子色谱分析的研究过程中,建立了以0.12mmol/L Na2CO3和0.15mmol/L Na2HCO3为淋洗液,12.5mmol/L H2SO4为微膜抑制器的再生液,用HPIC-AS3串联HPIC-AG3的色谱系统,一次进样50mL可在8min内检测出μg/L级的F^-、CH3COO^-、HCOO^-、Cl^-,方法简便、经济快捷。经实验,甲酸、乙酸的检出限分别为2.56μg/L和17.4μg/L,F^-、Cl^-为1.87μg/L和8.82μg/L;方法精密度的相对标准差在0.4%-2.0%范围,样品加标回收率在97.7%-103.5%之间,完全能够满足降水样品和大气样品中F^-、Cl^-和低碳有机酸(甲酸、乙酸)的分析要求。在同一系统中只需要增加淋洗液浓度,采用一级梯度洗淋亦可完成对同一样品中其他阴离子(NO3^-、SO4^2-、PO4^3-)的检测。 相似文献
998.
城市环境卫生专项规划的研究 总被引:1,自引:0,他引:1
叙述城市环境卫生专项规划编制工作的开展,分析新的影响因素,提高适应市场经济新时期的编制指导思想。 相似文献
999.
1000.