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391.
农业面源污染控制既要考虑技术对污染物的削减效果,也要兼顾工程建设-运行成本.以我国近20 a来农业(种植业、畜禽养殖业、水产养殖业)面源污染控制具有代表性的73种技术为对象,根据指标(总氮、总磷、氨氮、COD削减率,建设成本,运行成本)完整性等因素初步选择了12种技术,采用层次-灰色关联度法选择兼顾污染物削减率和成本的最适技术.结果表明:种植业污染控制技术中以农田排水植物-微生物复合处理技术为最好,其次是生态拦截沟渠技术;畜禽养殖业面源污染控制技术中以养殖废水土地渗滤处理系统为最好,其次是人工湿地技术;水产养殖业污染控制技术中以组合填料序批式生物膜法为最好,其次是生物-生态复合处理技术.针对太湖地区实际情况,生态拦截沟渠技术更适合该地区农田排水污染控制,土地渗滤处理系统可用于太湖上游地区畜禽养殖业废水处理,组合填料序批式生物膜法可以用于水产养殖排水处理.所提出的层次-灰色关联度法可满足兼顾污染物削减和工程建设-运行成本的面源污染控制技术比选和决策需求.  相似文献   
392.
Inductively coupled plasma with mass spectrometric detection (ICP-MS) has been used for clinical analysis of cobalt (Co) due to its sensitivity and specificity; however, media-specific validation studies are lacking. This study provides data on performance variables affecting differences between selected analytical platforms (Perkin Elmer and Agilent), tissue sample preparation, storage, and interferences affecting measurements in whole blood, serum, and synovial fluid. The limits of detection (LOD) range from 0.2–0.5 µg/L in serum and synovial fluid, and 0.6–1.7 µg Co/L in whole blood. The Agilent platform with collision reaction cell is more sensitive, while the Perkin Elmer platform with dynamic reaction cell demonstrates more polyatomic interferences near the LOD for serum and whole blood. Split sample analysis showed good accuracy, precision, and reproducibility between serum Co measurements using acid digestion or detergent dilution preparations for persons with metal hip implants or following supplement intake. The results demonstrated reliability of the ICP-MS methodology across the two analytical platforms and between two commercial laboratories for Co concentrations above 5 µg Co/L, but digestion procedures and polyatomic interferences may affect measurements in some media at lower concentrations. These studies validate the described ICP-MS methodology for clinical purposes with precautions at low cobalt concentrations (<5 µg Co/L).  相似文献   
393.
This paper examines how Australian land use plans incorporate provisions for sustainable urban form, design, biodiversity conservation, and climate change. Despite the long-standing sustainability objectives in state policy frameworks, a survey of 291 comprehensive plans finds implementation within local instruments is far from universal. Differences in patterns of policy adoption, as well as potential explanations for these differences, including geographical location, patterns of residential growth, the socio-economic composition of local communities, political forces, and policy evolution over time, are explored. Overall, areas experiencing more intensive growth tend to have newer plans, which in turn, contain more sustainability provisions, suggesting a responsive rather than repressive relationship between development pressures and regulatory development control.  相似文献   
394.
The fatty acids of two composts of active sludge with palm tree waste were investigated by thermochemolysis coupled to gas chromatography-mass spectrometry. This method (tetramethylammonium hydroxide-pyrolysis-gas chromatography-mass spectrometry) allowed the direct determination of total fatty acids (analysed as fatty acid methyl esters: FAMEs) present in the organic matter of the samples without any separation procedures. Mixture A was 1/3 sludge+2/3 palm waste and mixture B was 1/2 sludge+1/2 palm waste. The level of FAMEs rose by 8.4–33.3% and 10.8–13.4% in mixtures A and B, respectively, after 6 months of co-composting. Branched FAMEs of bacterial origin (iC15:0) rose during the thermophilic phase, in mixture A the aC17:0/aC15:0 ratio increased during the co-composting process, also in mixture B the aC16:0/C16:0 ratio rose but only during the thermophilic phase. All the FAMEs identified showed a drop at the end of co-composting except for C18:0 and C16:0. The stabilisation phase was characterised by a significant rise in the length of the aliphatic chains; the carbon preference index thus increased at the end of the composting process, indicating that the final product was proportionally richer in fatty acids of plant origin.  相似文献   
395.
This paper illustrates the early results of ongoing research developing novel methods to analyse and simulate the relationship between trasport-related air pollutant concentrations and easily accessible explanatory variables. The final scope is to integrate the new models in traditional traffic management support systems for a sustainable mobility of road vehicles in urban areas.This first stage concerns the relationship between the hourly mean concentration of nitrogen dioxide (NO2) and explanatory factors reflecting the NO2 mean level one hour back, along with traffic and weather conditions. Particular attention is given to the prediction of pollution peaks, defined as exceedances of normative concentration limits. Two model frameworks are explored: the Artificial Neural Network approach and the ARIMAX model. Furthermore, the benefit of a synergic use of both models for air quality forecasting is investigated.The analysis of findings points out that the prediction of extreme concentrations is best performed by integrating the two models into an ensemble. The neural network is outperformed by the ARIMAX model in foreseeing peaks, but gives a more realistic representation of the concentration's dependency upon wind characteristics. So, the Neural Network can be exploited to highlight the involved functional forms and improve the ARIMAX model specification. In the end, the study shows that the ability to forecast exceedances of legal pollution limits can be enhanced by requiring traffic management actions when the predicted concentration exceeds a lower threshold than the normative one.  相似文献   
396.
结合钢铁行业现有的清洁生产规范标准以及国内不锈钢行业清洁生产现状,采用层次分析法构建不锈钢行业清洁生产评价指标体系。采用此评价指标体系对国内典型不锈钢企业清洁生产水平进行评价,能够更全面、准确地反映其清洁生产水平。  相似文献   
397.
本文对发展中高效液相色谱及其联用技术在有机锡形态测定的应用分两部分作了综述:第一部分,各类高效液相色谱分离有机锡:第二部分,从接口角度讨论高效液相色谱及其联用技术测定有机锡。共引36 篇文献。  相似文献   
398.
我国东南沿海农村地区是世界上遭受台风灾害袭击最严重的地区之一。根据实地考察数据与分析资料,通过对台风灾害的全面风险分析与评估,依据应急过程的内在特点和避难所的功能特点,从台风避难场所的规划设计、内部硬件设施、外部软件环境三个方面出发,建立了层次化评价指标体系,应用层次分析法建立配置层次分析模型,确定指标权重,利用模糊综合评价法构建了评价模糊矩阵,进行模糊运算,得出综合评定结果。实例证明了该方法的有效性。  相似文献   
399.
400.
针对海洋文化产业发展战略研究中缺乏定量分析的不足,将SWOT分析法和层次分析法相结合,通过量化各影响因素的权重,得出薄弱的海洋文化产业综合竞争力和海洋文化人才队伍建设是制约秦皇岛海洋文化产业发展的关键因素.论证了秦皇岛海洋文化产业应充分利用资源禀赋丰富的优势,抓住国家战略政策机遇,采取开拓型战略,积极应对各种劣势和威胁,走“以海洋文化产业资源为依托,以海洋旅游产业为主导”的核心产业带动发展模式.  相似文献   
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