Property rights and governance of Africa's rangelands: A policy overview

Recent efforts at securing property rights in dryland Africa have generally involved several interrelated processes such as legal and policy reforms that recognize and strengthen customary rights or the seasonal rights of pastoralists, and the decentralization of land allocation and administration to lower governance levels. These solutions are in turn beset by new problems, key among them are establishing norms for local participation in decision making, preventing manipulation and capture by elites, lack of accountability of local level institutions and authorities, and the onset of a new generation of resource user conflicts. Increasing avenues through which dialogue and communication can occur among policy actors (including local communities) in order to mobilize multiple experiences, information, and to manage power relationships — a collaborative approach to policy governance — is one way of approaching the complexity paradox. This is anticipated to provide opportunity for learning, innovation and adaptability.     

基层环境监测站仪器期间核查存在的问题及改进措施

基层环境监测站承担着大量监测数据来源的责任,监测数据的质量不容忽视,但基层环境监测站普遍存在对仪器期间核查忽视的问题,严重影响数据质量的可靠程度,所以应根据仪器的性能和使用情况,在规定的时间间隔内,使用相应的核查方法,对仪器进行期间核查,及时预防和发现不合格的仪器并避免误用,保证监测结果持续的准确性、有效性,以维护环境监测站和客户的权益。     

垃圾渗滤液处理工艺及发展趋势探讨

分析了当前国内外几种渗滤液处理技术中存在的问题,以及渗滤液处理技术的发展方向。指出渗滤液处理技术应根据工程建设要求,并将渗滤液处理系统与垃圾焚烧系统结合起来确定,今后的发展方向和研究重点应放在渗滤液处理系统中的污泥处理系统、沼气净化及利用系统、膜系统浓缩液处理系统上。     

高锰酸盐指数在线自动监测仪的现状与问题

高锰酸盐指数在线自动监测仪,已在全国水质自动监测系统中得到广泛的应用,厂家对该产品生产日趋成熟,相关标准逐步出台,仪器性能基本达标。但在实际应用过程中,该仪器仍有许多问题需要进一步认识与改进。文中从标准溶液、终点判定、国家标准、干扰、比对、自动标定等几个方面,分析了该仪器存在的问题,并提出了相关建议。     

固定源废气监测工作的若干问题探讨

从监测工况、测点位置、采样过程、结果计算等方面,结合实际经验,对大气固定污染源的监测工作中存在的一些疑难问题进行了探讨。     

火电厂竣工环境保护验收工作的管理和建议

竣工环境保护验收是检查环保＂三同时＂制度执行情况的重要环节,也是环保监督管理的重要内容。从竣工环境保护验收工作的相关法律、法规出发,依据火电厂验收技术规范,并结合火电厂竣工环境保护验收工作实践,阐述了火电厂验收工作的相关规定及流程,并结合验收工作中经常出现的问题,给出改进建议。     

烟塔排烟电厂大气影响预测分析

在系统分析我国烟塔排烟电厂大气影响评价及其相关研究成果的基础上,指出应关注的几个问题,并结合烟塔排烟电厂的负荷变化特点提出了解决问题的基本思路及需要重点研究的专题。     

我国火电烟气脱硫存在的问题及对策建议

从电力装机结构、火电烟气脱硫现状、脱硫石膏排放现状等方面,分析了我国火电烟气脱硫目前存在的几个主要问题,并对烟气脱硫产业如何进一步科学发展提出了对策建议。     

Formation of multiple trimethylsilyl derivatives in the derivatization of 17α-ethinylestradiol with BSTFA or MSTFA followed by gas chromatography-mass spectrometry determination

N,O-bis(trimethylsily)trifluoroacetamide (BSTFA) and N-methyl-N(trimethylsily) trifluoroacetamide (MSTFA) are common derivatization reagents used in the GC-MS analysis of estrogen steroids such as estrone (E1) and 17(-ethinylestradiol (EE2). In this study, three trimethylsilyl (TMS) steroid derivatives, mono-and di-trimethylsilyl EE2 and mono-trimethylsilyl E1, were observed during the derivatization of EE2 with BSTFA or MSTFA and/or GC separation. Factors influencing the production of multiple TMS derivatives and their relative abundance were examined. It was found that both methanol and bisphenol A competed with estrogenic esteroids when reacting with silylation reagents, and thus affected the formation of TMS derivatives and their relative abundance in the derivatization products. Methanol was found to be more reactive than bisphenol A with the BSTFA reagent. None of the three solvents tested in this study could prevent the generation of multiple TMS derivatives during the derivatization of EE2 with BSTFA, followed by GC analysis. A similar result was observed using MSTFA as the derivative reagent followed by GC analysis. Thus, the suitability of BSTFA or MSTFA as the derivatization reagent for the determination of E1 and EE2 by GC-MS, under the conditions reported here, is questionable. This problem can be solved by adding trimethylsilylimidaz (TMSI) in the BSTFA reagent as recommended, and the performance of the method has been proved in this study.     

新疆水环境质量监测数据中存在问题的探讨

根据水环境质量监测数据审核工作实践,总结出目前新疆地、州、市环境监测站上报的水环境质量监测数据中存在的问题,并介绍和分析了几种常用的水质监测数据合理性判断的方法和依据,以期为新疆水环境质量监测工作提供可借鉴的建议。