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91.
循环经济的理念就是经济发展与环境保护“双赢”的理论.以新疆为例阐述了发展循环经济与环境保护的关系,认为发展循环经济是新疆环境保护的重要途径,提出了新疆发展循环经济的建议. 相似文献
92.
Removal of a type of endocrine disruptors-di-n-butyl phthalate from water by ozonation 总被引:1,自引:0,他引:1
Ozonation of synthetic water containing a type of endocrine disruptor-di-n-butyl phthalate (DBP) was examined. Key impact factors such as pH, temperature, ionic strength, ozone dosage and initial DBP concentration were investigated. In addition, the activities of radicals on uncatalysed and catalysed ozonation were studied. The degradation intermediate products were followed and the kinetic of the ozonation were assessed as well. Results revealed that ozonation of DBP followed two mechanisms. Firstly, the reaction rate of direct ozonation was slower at lower pH, temperature, and ionic strength. Secondly, when these factors were increased for indirect radical reaction, higher percentage of DBP was removed with the increase of the initial ozone dosage and the decrease of the initial DBP concentration. In addition, tea-butanol, humic substances and Fe(Ⅱ) affected DBP ozonation through the radical pathway. It was determined that ozonation was restrained by adding tea-butanol for its radical inhibition effect. Furthermore, humic substances enhanced the reaction to some extent, but a slight negative effect would be encountered if the optimum dosage was exceeded. As a matter of fact, Mn(Ⅱ) affected the ozonation by "active sites" mechanism. In the experiment, three different kinds of intermediate products were produced during ozonation, but the amount of products for each one of them decreased as pH, temperature, ionic strength and initial ozone dosage increased. A kinetic equation of the reaction between ozone and DBP was obtained. 相似文献
93.
为了研究采场在覆岩运动过程中关键层的缺失与否对综采工作面采场矿压的影响效果,采用相似模拟试验和数值模拟,对大柳塔煤矿活鸡兔井1-2煤21304综采工作面在回采期间出现的2次压架事故进行分析。研究结果表明:上覆岩层的关键层缺失与否对下部煤层的开采影响至关重要,尤其是对上部已采单一关键层的煤层回采影响较大,当上煤层的关键层未缺失时回采后形成稳定的砌体梁结构,其下煤层回采也易形成稳定的砌体梁结构,反之亦然;在冲沟发育较深的地形,关键层的形成也会受到冲沟影响,造成部分关键层缺失,当关键层缺失时工作面向坡开采,随着工作面所承受的荷载逐渐增大,出现动载矿压的几率也随之增加,背坡开采则与之相反。 相似文献
94.
长期以来,中国农村环境保护工作基础相对薄弱,国家环保部门于2014年出台《农村环境质量综合评价技术规定(试行)》。研究利用2015—2016年安徽省域的农村环境监测数据,将安徽省重点生态功能区考核县域的数据与其他县域监测数据进行分类整理,采用该技术规定开展农村环境质量综合评价,对评价体系的3个级别指标层面的评价结果进行对比,并通过2组数据的差异性分析,深度剖析评价体系各级指数的结果合理性,验证该评价技术规定的区域适用性;同时,根据各级指标对比中发现的问题,对评价体系的相关指标提出修改完善建议。 相似文献
95.
Pramod Chandra 《Natural resources forum》2020,44(3):274-285
The medicinal and aromatic plants resources of Uttarakhand, India offer significant opportunities of employment and livelihood for rural communities and contribute a large share in the medicinal and aromatic plants trade of India. With the growing trade of medicinal and aromatic plants resources in the global market, the medicinal and aromatic plants business of Uttarakhand is also continuously growing in terms of trade volume, value and market reach. But, considering the ecological importance as well as unregulated exploitations of these resources, the growing business activities in this sector appear incompatible to the sustainability agenda. Through a mini review, this study assesses the medicinal and aromatic plants sector of Uttarakhand and identifies key challenges that seem incompatible for resource and business sustainability and offers some prospective research directions essential for identifying pragmatic solutions to support sustainability in the sector. This review identifies nine key challenges to sustainability in Uttarakhandʼs medicinal and aromatic plants sector. It is therefore pertinent that future research focus on the prevailing challenges of the medicinal and aromatic plants sector of Uttarakhand to develop strategies for sustainable business prospects. 相似文献
96.
对指纹加密算法进行整体介绍,并加入纠错机制,设计了带纠错功能的指纹加密算法。该法利用二进制序列发生器生成随机以多项式的系数形式的密钥,将指纹点加密,在密钥恢复阶段用拉格朗日差值来恢复多项式,并利用循环冗余校验码进行校验,可以保证找到最准确的密钥来保证多项式的准确度。实验结果表明:利用带有纠错码的模糊金库算法很好地实现了指纹模板的加密和解密,从而达到了保护生物信息安全的要求;通过密钥长度增长可以提高系统的安全性能。 相似文献
97.
安全生产责任的制度整合与伦理道德建设 总被引:4,自引:3,他引:1
在分析安全生产责任危机含义和安全生产责任概念基础上,指明安全生产责任体系的"四要素",即道德责任、政治责任、法律责任与管理责任,重点阐明道德责任是该体系的基础要素及其意义。根据对我国现有安全生产责任制度的分析,提出一个关于安全生产责任制度建设的伦理框架:强化安全生产责任意识;用人权伦理原则对安全生产责任制度伦理化;以特定的安全生产责任的伦理规范和准则构建责任规则系统;强化责任主体道德素质培养与监察制度建设,促使其自觉履行好自身应负的安全生产责任。总之,该理论框架为安全生产责任制度建立提供一个新的伦理学基础。 相似文献
98.
公钥基础设施(PKI)安全性研究 总被引:2,自引:0,他引:2
田仲富 《中国安全科学学报》2009,19(2)
详细介绍公钥基础设施(PKI)的基本概念、PKI的基本框架组成以及其各部分的主要特征、功能;重点对PKI的安全性问题作了剖析,当前PKI的最主要安全缺陷表现在两个方面:其一,政策性缺陷即PKI本身的标准不一,没有一个统一的国际标准;其二,即PKI在应用中的合理性问题主要包括其证书认证、密钥的安全性以及密钥的长度等问题。对于PKI的自身及其使用缺陷,笔者认为应由相关权威部门尽早地制定出一套统一的标准,另外,还要相应地增强其公钥加密算法以及采用合理的密钥长度,进而完善证书的颁发、撤销以及认证等问题。 相似文献
99.
Brack W Klamer HJ López de Alda M Barceló D 《Environmental science and pollution research international》2007,14(1):30-38
Background, Aim and Scope
Extensive monitoring programs on chemical contamination are run in many European river basins. With respect to the implementation
of the European Union (EU) Water Framework Directive (WFD), these programs are increasingly accompanied by monitoring the
ecological status of the river basins. Assuming an impact of chemical contamination on the ecological status, the assignment
of effects in aquatic ecosystems to those stressors that cause the effects is a prerequisite for taking political or technical
measures to achieve the goals of the WFD. Thus, one focus of present European research is on toxicant identification in European
river basins in order to allow for a reduction of toxic pressure on aquatic ecosystems according to the WFD.
Main Features:
An overview is presented on studies that were performed to link chemical pollution in European river basins to measurable
ecotoxic effects. This includes correlation-based approaches as well as investigations that apply effect-directed analysis
(EDA) integrating toxicity testing, fractionation and non-target chemical analysis. Effect-based key toxicants that were identified
in European surface waters are compiled and compared to EU priority pollutants. Further needs for research are identified.
Results:
Studies on the identification of effect-based key toxicants focused on mutagenicity, aryl hydrocarbon receptor-mediated effects,
endocrine disruption, green algae, and invertebrates. The identified pollutants include priority pollutants and other well-known
environmental pollutants such as polycyclic aromatic hydrocarbons, polychlorinated dibenzo-p-dioxins, furans, and biphenyls,
nonylphenol, some pesticides and tributyltin, but also other compounds that were neither considered as environmental pollutants
before nor regulated such as substituted phenols, natural or synthetic estrogens and androgens, dinaphthofurans, 2-(2-naphthalenyl)benzothiophene,
and N-phenyl-2-naphthylamine.
Discussion:
Individual studies at specific sites in a European river basin demonstrated the power of combined biological and chemical
analytical approaches and, particularly, of effect-directed analysis. However, the available information on effect-based key
toxicants is very limited with respect to the entirety of rivers possibly at risk due to chemical contamination and with respect
to toxicological endpoints considered at a specific site. A relatively broad basis of information exists only for estrogenicity
and aryl hydrocarbon, receptor-mediated effects.
Conclusions:
The development of tools and strategies for an identification of key toxicants on a broader scale are a challenging task for
the next years. Since investigations dealing with toxicant identification are too labor and cost-intensive for monitoring
purposes, they have to be focused on the key sites in a river basin. These should include hot spots of contamination, particularly
if there is evidence that they might pose a risk for downstream areas, but may also involve accumulation zones in the lower
reach of a river in order to get an integrated picture on the contamination of the basin.
Perspectives:
While EDA is almost exclusively based on measurable effects in in vitro and in vivo biotests to date, an increasing focus
in the future should be on the integration of EDA into Ecological Risk Assessment and on the development of tools to confirm
EDA-determined key toxicants as stressors in populations, communities and ecosystems. Considering these requirements and applied
in a focused way, toxicant identification may significantly help to implement the Water Framework Directive by providing evidence
on the main stressors and possible mitigation measures in order to improve the ecological status of a river ecosystem. 相似文献
100.