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141.
研究了氯化镉、灭多威和硝基苯对孵化以后7d左右日本青鳉(Oryzias latipes)行为毒性。结果表明,在不同污染物中,随暴露浓度的增加,第1尾日本青鳉产生行为抑制的时间逐渐缩短,并且半数行为抑制时间(time ofhalf behavior inhibition,THBI,Y)随暴露浓度(X)呈现幂指数关系Y=aXb,其中20相似文献   
142.
143.
介绍一种基于微机的有毒有害物质判定方法。用模糊聚类分析法对已有化学品知识库分类。通过对化学品事故现场观察到的综合信息的核查和量化,根据一个判定准则和优化方案,找到未知化学品的归属,同时给出一个比较保守的判断结果,作为突发事故的急救处理和对环境危害的快速评估依据。  相似文献   
144.
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   
145.
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   
146.
The mechanical properties, including strength, deformational behavior, and wetting softening phenomena of municipal solid waste incinerator (MSWI) bottom ash are one of the major concerns for reuse applications. However, owing to the complex constituents of municipal solid waste, the properties of MSWI bottom ash are often highly variable. A series of artificial specimens with controlled chemical components were tested in this study. The test results show that the artificial bottom ash possesses the following mechanical characteristics: (1) for the strength, the frictional angles of the bottom ash under dry and saturated conditions vary from 34.8° to 51.1° and 26.0° to 37.2°, respectively; (2) for the deformation, the shear stiffness increases with the normal stress arises and degrades upon increased shearing; (3) significant wetting degradation of the strength and stiffness were observed.The multi-variable regression analysis was conducted to evaluate the associated influence of the chemical components on the strength. Among the evaluated components, Fe2O3 and Al2O3 are key factors; an increase in either results in higher strength at both dry and saturated conditions. The results were used to propose empirical relationships for ?dry and ?sat, expressed in terms of Fe2O3 and Al2O3. Accordingly, a strength classification chart is proposed for engineering purposes.  相似文献   
147.
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   
148.
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   
149.
This study employs the notion of environmental value orientations as an approach to examine the relationships between forest value orientations and demand on services available in the National Forest Recreation Areas in Taiwan. Data for this investigation were collected from on-site, off-site, and online surveys (n = 1919). Statistical results suggest that the authorities should highlight the role of Taiwanese forest as public property with aesthetic, historic, and cultural values, and the use of more comprehensive dimensions of environmental value orientations is warranted when using value-related variables to address natural resource management issues. The correlation evidence of service demands of tourists with different forest value orientations indicates that the authorities should focus on maintaining and improving basic services available in the National Forest Recreation Areas.  相似文献   
150.
井喷是海上钻井平台的重要威胁,而人因失误又是造成井喷的主要原因,所以对井喷事故人因失误分析对指导海上钻井安全有重要意义。本文建立了井喷事故人因失误类故障树模型,并对此进行定量分析。根据井喷事故的4个指标并结合风险图得到降低风险所需的置信水平,然后使用训练屏障和 GPS 定位屏障将风险降低到可接受水平。最后通过蝴蝶结模型将安全屏障对风险的影响清楚的展示出来,为人因失误的预防和控制提供指导。  相似文献   
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