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151.
松树近旁土壤酸化的二维特征   总被引:1,自引:0,他引:1       下载免费PDF全文
采用土壤酸中和能力的一种新定义方法:土壤水的pH值降低到4.7时100g土壤消耗的H+量,研究了土壤断面的酸化特征。选择了南方的红壤和北方的褐壤,详细研究了松树近旁土壤pH、酸中和能力、以及对SO24吸附等断面的二维分布特征。结果表明,松树近旁土壤的pH、酸中和能力、SO24吸附能力在水平层变化不明显,在垂直深度方向逐渐变大,表层小于下层。从土壤断面ANC的特征揭示出我国南北方土壤表层均受不同程度的酸化。  相似文献   
152.
Thuan NT  Tsai CL  Weng YM  Lee TY  Chang MB 《Chemosphere》2011,83(6):760-766
Twenty-one fresh water samples were taken from reservoirs, wells and drinking water treatment plants in Taiwan for measurement of polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/F) concentrations. Due to low concentration of PCDD/Fs, water samples (400-1000 L) were collected by using the on-site large volume pre-concentration system and analyzed by high resolution gas chromatography (HRGC)/high resolution mass spectrometer (HRMS). Different characteristics of dioxin profiles in surface water and groundwater are observed. The PCDD/F concentrations in fresh water samples varied from 0.001 to 0.265 pg WHO98-TEQ/L which are lower than the standard (12 pg WHO98-TEQ/L) set by the Taiwan Environmental Protection Administration (TEPA) for drinking water. Only a small fraction (<5%) of the total PCDD/F concentration in fresh water samples was water-soluble. As a result of their hydrophobicity, PCDD/Fs are effectively removed along with suspended solid via the water treatment process (average 98% removal efficiency).  相似文献   
153.
In order to develop a sound material-cycle society, cost-effective municipal solid waste (MSW) management systems are required for the municipalities in the context of the integrated accounting system for MSW management. Firstly, this paper attempts to establish an integrated cost-benefit analysis (CBA) framework for evaluating the effectiveness of MSW management systems. In this paper, detailed cost/benefit items due to waste problems are particularly clarified. The stakeholders of MSW management systems, including the decision-makers of the municipalities and the citizens, are expected to reconsider the waste problems in depth and thus take wise actions with the aid of the proposed CBA framework. Secondly, focusing on the financial cost, this study develops a generalized methodology to evaluate the financial cost-effectiveness of MSW management systems, simultaneously considering the treatment technological levels and policy effects. The impacts of the influencing factors on the annual total and average financial MSW operation and maintenance (O&M) costs are analyzed in the Taiwanese case study with a demonstrative short-term future projection of the financial costs under scenario analysis. The established methodology would contribute to the evaluation of the current policy measures and to the modification of the policy design for the municipalities.  相似文献   
154.
用Na_2CO_3作为助溶剂、Na_2O_2作为消解剂,采用微波焙烧法和马弗炉焙烧法消解处理废钒钨钛脱硝催化剂。通过XRF、BET、XRD和NH_3-TPD技术对两种消解方法制得的钛钨粉样品进行了表征。表征结果显示,与马弗炉焙烧法相比,微波焙烧法得到的钛钨粉纯度更高,TiO_2与WO_3含量之和大于96.7%(w),且该钛钨粉还具有更高的比表面积和酸性,可以作为钒钨钛脱硝催化剂的生产原料再利用。  相似文献   
155.
The term ‘indicator’ is often vague and heterogeneous, and its dynamic characteristics make it highly variable over time and space. Based on reviews and synthesis, this study visualizes phenomena and highlights the trend of indicator selection criteria, development methods, validation evaluation strategies for improvement. In contextualization of the intensification of agriculture and climate change, we proposed a set of indicators for assessing agricultural sustainability in Bangladesh based on theoretically proposed and practically applied indicators by researchers. Also, this article raises several issues of indicator system development and presents a summary after due consideration. Finally, we underline multi-stakeholders’ participation in agricultural sustainability assessment.  相似文献   
156.
噪声治理技术实例研究   总被引:1,自引:0,他引:1  
文章从噪声源入手,分析泵房和压缩机房内的噪声对工作人员和居民不同程度的影响和危害,按照噪声控制的原理,采取吸声、隔声、消声相结合的降噪措施。治理后,泵房、压缩机房内噪声值低于85 dB(A),压缩机房厂界噪声值低于60 dB(A),居民楼外1 m处的噪声值低于45 dB(A),有效减少噪声对作业场所和周边环境的污染。  相似文献   
157.
近年来,SiC材料作为一种新型的柴油车尾气颗粒物过滤材料获得了迅速发展,正逐步取代目前广泛应用的堇青石多孔陶瓷材料.结合堇青石和SiC过滤材料的性能特点,重点概述了2种SiC改性过滤材料(重结晶SiC.RSiC和硅结合SiC,Si-SiC)的研究和应用进展,并介绍了SiC颗粒物过滤器的市场现状和发展前景.  相似文献   
158.
Rice farming sustainability assessment in Bangladesh   总被引:1,自引:0,他引:1  
Farming sustainability is primordial to long-term socioeconomic development. This study assesses rice farming sustainability in Bangladesh by developing a composite indicator (CI) under the four pillars of sustainability and examines the main determining factors. The assemblage of top-down and bottom-up approaches were applied to generate an essential set of indicators and data were collected through a household survey from 15 villages of three major rice growing ecosystems. The results revealed that less than half of the rice growers were sustainable in terms of economical viability, ecological benefits, and quality of life. By category, Boro rice farming was found to be the most sustainable, followed by Aman and Aus rice farming. Human capital development, increasing land productivity, use of resource conserving practices and technologies, and information availability and accessibility were the main factors promoting rice farming sustainability. The findings indicated that the construction of CI by employing several methodologies such as normalisation provide straightforward and clear-cut policy inputs. The major policy implications that emerged from the findings of the study are outlined to actualise rice farming sustainability, which contributes to sustainable development in Bangladesh.  相似文献   
159.
对平果热电厂皮带上煤除尘系统失效进行了故障诊断 ,对故障产生的主要原因诱导风流进行了详细的分析 ,采取了可行的改进措施  相似文献   
160.
Natech事件风险评估研究进展   总被引:1,自引:0,他引:1  
盖程程  翁文国  袁宏永 《灾害学》2011,26(2):125-129
Natech(自然灾害诱发事故灾难)事件在全球大范围内发生,造成了严重的人员伤亡、经济损失和环境破坏,已经成为风险评估领域新的研究热点之一。回顾了Natech事件的相似研究和被单独提出后的研究历程,包括:灾害链和灾害链式理论研究、多米诺效应研究和Natech事件定量风险评估研究。简要评析了目前主要的三类Natech事件研究思路:损失模型、评估指标体系和预警时间指标,并根据Natech风险评估结果,对应对Natech事件提出建议。  相似文献   
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