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841.
为了探究厌氧颗粒污泥用于氢辅助原位生物法沼气提纯的可行性,在高氢分压ASBR中对厌氧颗粒污泥演变过程进行了考察,包括反应器性能和厌氧颗粒污泥特性变化情况.结果表明,在进水COD负荷低于5g/(L·d)时,氢辅助原位生物法沼气提纯中高氢分压、高进水COD负荷和高剪切力新环境促使厌氧颗粒污泥向小粒径方向演变,系统运行性能良好、高效,此时厌氧颗粒污泥可以通过营造具有极低氢分压的微环境强化基于HIT(种间氢传递)途径丙酸降解;但随着进水COD负荷进一步提高,超过6g/(L·d)时,系统出现不可控的丙酸积累.因此,需要寻求其他技术手段来缓解更高进水COD负荷条件下氢辅助原位生物法沼气提纯系统中丙酸积累问题.  相似文献   
842.
矿井瓦斯治理有多种方法,联合几种抽采方式综合治理瓦斯,效果较佳,可提高煤层开采的安全性,创造良好的井下环境。  相似文献   
843.
The UNFCCC requires REDD+ countries wishing to receive results-based payments to measure, report and verify (MRV) REDD+ impacts; and outlines technical guidelines and good governance requirements for MRV. This article examines institutional effectiveness of REDD+ MRV by assessing countries’ progress in implementing these technical guidelines and good governance requirements, from three dimensions. Ownership of technical methods examines whether countries own technical methods for forest area and area change measuring, and for estimating forest carbon stocks; and whether national MRV systems cover all forests, land uses and carbon pools. Administrative capacity examines development of administrative competence to implement MRV. Good governance examines whether countries espouses norms of good governance in their MRV systems. We apply these dimensions to assess and compare progress in 13 REDD+ countries, based on a review of national and international documents. Findings show that REDD+ countries have high to very high ownership of technical methods. However, majority ranks only low to moderate on administrative capacity and good governance. This means that although countries have started developing technical methods for MRV, they are yet to develop the competence necessary to administer MRV and to inculcate good governance in MRV. The article explain the scores and suggest ways of improving implementation of REDD+ MRV.  相似文献   
844.
基于热光反射法(IMPROVE A)和热光透射法(RT-Quartz)二种协议分析方法和新型OC/EC分析方法对济南市碳质气溶胶含量进行了对比观测.结果表明,协议方法在OC/EC的观测过程中因分析定义会造成碳质气溶胶质量浓度高估或者低估,且膜采样系统使离线分析的OC约为在线的1.65倍,而新型OC/EC测量方法相对于2种协议方法,去除了原理上和环境参数(如VOCs)可能导致的误差,在OC/EC/TC测量结果上均有一定优势,在实际运行中更具有准确性、稳定性和实用性,更加适合颗粒物中OC/EC长期业务化在线测量.  相似文献   
845.
Consideration is given to uncertainties related to methods for assessing the above and belowground phytomass and primary production of forest stands in test plots, as well as for extrapolating the results to forested areas.  相似文献   
846.
硝基苯作为一种具有稳定化学性质、高毒性、难降解性和易在生物体内积累的优先污染物,其环境污染治理越来越受到科研工作者的关注。综述了近年来国内外含硝基苯废水处理技术的研究进展,阐述了物理法、化学法、生物法和复合处理方法降解含硝基苯废水的机理,并探讨了其优缺点。指出将现有的各种处理技术进行高效整合并降低成本是今后处理含硝基苯废水的研究方向和重点。  相似文献   
847.
The importance of team mental models (TMMs) - team members’ shared and organized understanding of relevant knowledge - for teamwork and team-performance, particularly in high-risk industries, has been recognized for almost two decades. In healthcare, however, systematic investigations on the influence of TMM on teamwork and team-performance had yet to be conducted at the time of this review, despite many authors considering the concept to be useful for medical teams. The lack of measurement procedures appropriate for settings as complex and dynamic as, for example, the operating room, represents a major obstacle for empirical research in healthcare. We systematically reviewed empirical studies on TMMs aiming to identify methods that could be applied in healthcare. In particular, we analyzed the methods used, and situations in which TMMs have been investigated. The reviewed studies were sorted according to task and team characteristics. We discuss the results of this review with regard to characteristics of healthcare teams including anaesthesia teams and teams of ward nurses. Each of these examples represents a distinct teamwork setting (e.g. long- vs. short-lived teams) and hence requires a different approach to TMM measurement (e.g. focus on task-model vs. focus on team-model). Implications for study design, feasible measurement approaches, and questions for future research on TMMs in healthcare are discussed. In sum, our findings highlight the possible significance of TMM research in healthcare and its potential benefits for team-performance and, ultimately, patient safety.  相似文献   
848.
The conception, design, and implementation of sustainable development strategies in an organization aims at meeting and balancing economic, social, and environmental needs of internal and external stakeholders. While the principles and fundamentals of sustainability assist during the conception and design phases, the implementation process of management strategies – impacted directly or indirectly by internal and external factors – may identify areas of competitive advantages or challenges that would impede the projects and organizations’ performance targets. An organization is not an isolated entity and its performance is often compared against others in the market arena; therefore, assessment tools, benchmarking processes, and reporting strategies become essential for the understanding of the efforts made towards the implementation of plan, policies, and programs at the organization and project levels. A framework for a hybrid process-criterion benchmarking methodology is proposed in this paper. The framework integrates the Rank Xerox benchmarking process and the Wa-Pa-Su project sustainability rating system assessment methodology. The proposed hybrid process-criterion benchmarking methodology encourages the diversification in the development and implementation of sustainable and environmental rating systems in industry contexts (e.g., oil and gas, mining, heavy industrial, and energy) and aims for the improvement of existing sustainability performance assessment and reporting practices. It also assists the quantitative assessment process of advances and/or setbacks in sustainability performance and the implementation of continuous performance improvement programs.  相似文献   
849.
环境污染物能够以多种途径进入生物体内,在体内产生含氧自由基等活性氧物质,并通过多种信号通路及酶反应引起氧化应激,造成生物体内的脂质过氧化、蛋白质损伤、DNA表达改变、酶失活等,从而引发心血管疾病、风湿类疾病、感染及癌症等的发生。本文对环境污染物致氧化应激产生的原因、涉及的信号通路及酶反应、造成的危害,以及常见的基于细胞模型的氧化应激检测方法进行了综述,期望为评价环境污染物和检测氧化损伤提供参考。  相似文献   
850.
The dynamics of agricultural and forestry biomass are highly sensitive to climate change, particularly in high latitude regions. Heilongjiang Province was selected as research area in North-east China. We explored the trend of regional climate warming and distribution feature of biomass resources, and then analyzed on the spatial relationship between climate factors and biomass resources. Net primary productivity (NPP) is one of the key indicators of vegetation productivity, and was simulated as base data to calculate the distribution of agricultural and forestry biomass. The results show that temperatures rose by up to 0.37°C/10a from 1961 to 2013. Spatially, the variation of agricultural biomass per unit area changed from -1.93 to 5.85 t·km–2·a–1 during 2000–2013. More than 85% of farmland areas showed a positive relationship between agricultural biomass and precipitation. The results suggest that precipitation exerts an overwhelming climate influence on agricultural biomass. The mean density of forestry biomass varied from 10 to 30 t·km–2. Temperature had a significant negative effect on forestry biomass in Lesser Khingan and northern Changbai Mountain, because increased temperature leads to decreased Rubisco activity and increased respiration in these areas. Precipitation had a significant positive relationship with forestry biomass in south-western Changbai Mountain, because this area had a warmer climate and stress from insufficient precipitation may induce xylem cavitation. Understanding the effects of climate factors on regional biomass resources is of great significance in improving environmental management and promoting sustainable development of further biomass resource use.
  相似文献   
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