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391.
本文介绍了通过现场调查和实验研究,对六个城市的564座公共厕所进行了分析,结果为:水冲式公厕较非水冲式公厕卫生条件好,用卫生学指标评价水冲式公厕也明显好于非水冲式公厕.水冲式公厕臭气氨的浓度最低值0.11mg/m~3,最高值13.72mg/m~3,硫化氢最低值未检出,最高值0.006mg/m~3;蝇平均少于30只,蛆基本无.非水冲式公厕臭气氨的浓度最低值0.3mg/m~3,最高值26.47mg/m~3.硫化氢最低值未检出,最高值0.385mg/m~3;蝇平均多于30只顺每厕蹲位内多于15尾.研究表明公厕恶臭气体、蝇及她对城市环境和生态有明显的污染,应引起重视并加强改造和管理.  相似文献   
392.
The complexation behaviours of trivalent rare earth elements (La, Ce, Ho and Yb) by two types of humic acids were investigated under a specified set of conditions. Humic acids show quite different complexation capacities an conditional formation constants with the REEs. Apparently there are two types of binding sites in the functional groups of humic acid, in which the first binding sites have stronger ability than the second. Cerium shows the largest complexation capacities and highest formation constants among the four REEs with two humic acids, this anomaly may be relative to the distribution pattern of the REEs in seawater. The experimental results were comparable to the values of other metals reported and provided the basic data for the environmental geochemistry of rare earth elements.  相似文献   
393.
利用野外考察资料系统地计算和确定了1668年郯城地震的震源参数,讨论其特点进而提出了计算地震断层动摩擦阻力和应力的公式,给出了衡量地震断层破裂彻底度的判别指标和主震后强余震的预测方法  相似文献   
394.
以大连市为研究区域,构建人文因素对区域生态系统影响的指标体系、评估模型及评估标准,基于状态空间法,从区域资源、区域环境、人文因素三个维度对大连市2002-2012期间47个指标,评价人文因素对生态环境的影响。结果表明:近十二年来,大连市人文因素对生态环境的影响综合指数几乎都在临界值以下,即处在影响适度范围内,总体上达到了可持续发展的要求,但是与青岛市相比,大连市还应该加强生态环境保护的力度,避免在以后的发展中受到环境的制约。  相似文献   
395.
建立了全自动甲基汞分析仪测定水源水中甲基汞的方法,过程简单,可获得较理想的结果.实验采用直接法测定水源水中的甲基汞含量,优化仪器分析条件;在0 ~1 000 pg的范围内,标准工作曲线线性良好;仪器检测限达到0.003 ng/L,低于水源水中限量要求;实际水样加标回收率在86.5% ~935%之间;标准样品分析合格;测定标准样品的相对误差为1.4%;运用适当的质控手段,可较好的满足水源水中痕量甲基汞的测定需求.  相似文献   
396.
The rapidly growing industrial activities in emerging economies such as China have been causing resource depletion and pollution problems. This reality requires China to adopt an integrated management approach to resolve the conflict between industrial development and environmental protection, and the concept of circular economy (CE) serves this purpose. In this paper, we examine if different types of manufacturing enterprises on environmental-oriented supply chain cooperation (ESCC) exist. We also determine if the Chinese manufacturer types varying in ESCC differ in their implementation of the CE practices towards achieving the CE-targeted goals on improving both environmental and economic performance. Our cluster analytic results with multivariate analysis of variance (MANOVA) among the four identified types of Chinese manufacturers varying in environmental-oriented supply chain cooperation highlight the importance to intensify the cooperation with upstream and downstream supply chain partners for a CE initiative to succeed.  相似文献   
397.
The major features of different road sections were identified. Methods quantitatively determining the ecological impact of highway construction were discussed, and a demonstration was presented. The Dabao highway (from Dali to Baoshan) and the Sixiao highway (from Simao to Xiaomengyang) passing through the Longitudinal Range-Gorge Region were used as examples in this paper. For the normal road sections having no important species to protect, a method of ecosystem health assessment was introduced to calculate the overall range of the ecological impact of highway construction. For the road sections having plants or soils of interest, indexes were selected and the range of impact was determined using mathematical methods such as regression analysis and variance analysis. The range of impact on animal populations was also discussed in terms of the minimum living areas required by animal populations and the fragmentation caused by highway construction. The results indicate that the zones impacted by highway construction were composed of both regular and anomalous figures, the range of impacts for different landforms of the two sample highways were substantially different; highway construction had dramatic effects on roadside ecosystem health; the impact on soil factors of farmland was greater than 200 m, and the distance may exceed 1000 m when important large animals were considered.  相似文献   
398.
Effects of pH, temperature, and oxygen on the production and release of phosphine in eutrophic lake sediments were investigated under laboratory tests. Results indicated that the elimination of matrix-bound phosphine was accelerated under initial pH 1 or 12. Phosphine levels could reach maximum under initial pH 10. The contents of phosphine increased with the addition of alkali under pH 4–12. The rates of phosphine production and release from lake sediments varied with temperature. 20°C was the most favorable temperature for the production of matrix-bound phosphine. Oxygen showed little effect on matrix-bound phosphine. Matrix-bound phosphine concentrations in lake sediments were concluded to be dependent on a balance of natural generation and depletion processes.  相似文献   
399.
提出了一个具有全新运转方式的新型RBC系统-回转升降生物接触工艺。通过清水充氧实验考查了实验装置的充氧能力;通过正交试验,确定了最佳运行条件;在最佳运行条件下,研究了本工艺处理有机废水的性能和效果。  相似文献   
400.
The characteristics of Aerosol Optical Depth (AOD) and Angstrom exponent were analyzed and compared using Cimel sunphotometer data from 2007 to 2008 at five sites located in the Yangtze River Delta region of China. The simultaneous measurements between Lin’an and ZFU showed a very high consistency of AOD at all wavelengths. The differences are less than 0.02 for Angstrom exponent and AOD at all wavelengths. The mean values of AOD at 440 nm at the Pudong, Taihu and Lin’an were about 0.74 ± 0.43, 0.85 ± 0.46, and 0.89 ± 0.46, respectively. The mean values of Angstrom exponents were about 1.27 ± 0.30, 1.20 ± 0.28 and 1.32 ± 0.35, respectively. The variation of monthly averaged AOD over Pudong showed a single peak distribution, with the maximum value occurring in July (AOD440nm 1.26 ± 0.61) and minimum in January (AOD440nm 0.50 ± 0.27). However, the variations of monthly averaged AOD at Taihu and Lin’an showed a bi-modal distribution. There were peak values of AOD occurring in July (AOD440nm 1.41 ± 0.49) and September (AOD440nm 1.22 ± 0.52) for Taihu. For Lin’an, the two peak values of AOD occurred in June (AOD440nm 1.17 ± 0.69) and September (AOD440nm 1.28 ± 0.46). The AOD accumulated mainly between 0.30–0.90(68%), 0.30–1.20(75%) and 0.30–1.20 (~75%) at Pudong, Taihu, and Lin’an, respectively. The Angstrom exponent accumulated mainly between 1.10–1.60 (75%), 1.10–1.50 (63%) and 1.20–1.60, 50% (50%) at Pudong, Taihu, and Lin’an, respectively.The synchronized observation showed that the AOD at Pudong was larger than those at Dongtan by 0.03, 0.03, 0.04, 0.07, and 0.08 at wavelengths of 1020 nm, 870 nm, 670 nm, 500 nm and 440 nm, respectively. The synchronized observations at Pudong, Taihu and Lin’an showed that the three stations had high level AOD with means at 440 nm about 0.68, 0.73, and 0.78, respectively. The relationship between MODIS retrieved and ground-based measured AOD shows good agreement with R2 ranging from 0.68 to 0.79 at Pudong, Taihu, Lin’an and Dongtan. The MODIS results were overestimated comparing the ground measurements at Pudong, Taihu, and Dongtan but exceptional at Lin’an.The analysis results between aerosol optical properties and wind measurement at Pudong showed that the wind speed from the east correlates with the lower observed AOD. The back trajectory analysis indicates that more than 50% airmasses were from the marine area at Pudong, while back trajectories distribution is relatively homogeneous at Lin’an.  相似文献   
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