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111.
以汶川地震灾后恢复重建利用世行优惠紧急贷款四川省城镇市政基础设施项目环境监理开展情况为例,阐述了城镇基础设施建设项目环境监理开展过程中的重点,并分析了环境监理方案和环境监理的形式,通过对环境监理工作的经验总结分析,提供了一些建议以供参考,以期对其他城镇基础设施建设项目施工期环境监理工作的开展提供借鉴意义。  相似文献   
112.
江西某生物化工有限公司在生产乳酸的过程中产生大量高浓度有机废水,采用IC+A/O+BIOFOR联合工艺进行处理。当进水ρ(COD)平均为5 483 mg/L,ρ(NH3-N)平均为97.83 mg/L时,出水ρ(COD)平均为84 mg/L,去除率达98%;出水ρ(NH3-N)平均为12.07 mg/L,去除率为88%...  相似文献   
113.
Impervious surfaces are the result of urbanization that can be explicitly quantified, managed and controlled at each stage of land development. It is a very useful environmental indicator that can be used to measure the impacts of urbanization on surface runoff, water quality, air quality, biodiversity and microclimate. Therefore, accurate estimation of impervious surfaces is critical for urban environmental monitoring, land management, decision-making and urban planning. Many approaches have been developed to estimate surface imperviousness, using remotely sensed data with various spatial resolutions. However, few studies, have investigated the effects of spatial resolution on estimating surface imperviousness. We compare medium-resolution Landsat data with high-resolution SPOT images to quantify the imperviousness in Beijing, China. The results indicated that the overall 91% accuracy of estimates of imperviousness based on TM data was considerably higher than the 81% accuracy of the SPOT data. The higher resolution SPOT data did not always predict the imperviousness of the land better than the TM data. At the whole city level, the TM data better predicts the percentage cover of impervious surfaces. At the sub-city level, however, the ring belts from the central core to the urban-rural peripheral, the SPOT data may better predict the imperviousness. These results highlighted the need to combine multiple resolution data to quantify the percentage of imperviousness, as higher resolution data do not necessarily lead to more accurate estimates. The methodology and results in this study can be utilized to identify the most suitable remote sensing data to quickly and efficiently extract the pattern of the impervious land, which could provide the base for further study on many related urban environmental problems.  相似文献   
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115.
The solid acid catalyst, N–F codoped TiO2/SiO2 composite oxide was prepared by a sol–gel method using NH4F as nitrogen and fluorine source. The prepared materials were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), X-ray photoelectron spectroscopy (XPS), UV–Visible diffuse reflectance spectroscopy (UV–Vis), ammonia adsorption and temperature-programmed desorption (NH3-TPD), in situ Fourier transform infrared spectroscopy (FT-IR) and N2 physical adsorption isotherm. The photocatalytic activity of the catalyst for acrylonitrile degradation was investigated under simulant solar irradiation. The results showed that strong Lewis and Brønsted acid sites appear on the surface of the sample after N–F doping. Systematic investigation showed that the highest photocatalytic activity for acrylonitrile degradation was obtained for samples calcined at 450°C with molar ratio (NH4F to Ti) of 0.8. The degradation ratio of 71.5% was achieved with the prepared catalyst after 6-min irradiation, demonstrating the effectiveness of photocatalytic degradation of acrylonitrile with N–F codoped TiO2/SiO2 composite oxide. The photocatalyst is promising for application under solar light irradiation. Moreover, the intermediates generated after irradiation were verified by gas chromatography–mass spectrometry (GC–MS) analysis and UV–Vis spectroscopy to be simple organic acids with lower toxicity, and the degradation pathway was also proposed for acrylonitrile degradation with the prepared catalyst.  相似文献   
116.
It is well-known that Poria vaporaria (Pers.:Fr.) Cooke, Paecilomyces variotii Bainier and Aspergillus niger are fungi and molds which destroy bamboo. The aim of this study was to compare the effectiveness of antibacterial activity of 16 flavonoids in preventing the actions of these three bamboo-destroying fungi and molds (Poria vaporaria (Pers.:Fr.) Cooke, Paecilomyces variotii Bainier and Aspergillus niger). The results showed that baicalein(1) exerted the highest inhibitory effect on Poria vaporaria (Pers.:Fr.) Cooke and Paecilomyces variotii Bainier indicating that baicalein(1) may be considered as a potential agent to develop as natural bactericide to preserve natural bamboo.  相似文献   
117.
Constructed wetland (CW) and constructed pond (CP) are commonly utilized for removal of excess nutrients and certain pollutants from stormwater. This study characterized shallow groundwater quality for pre- and post-CW and CP system conditions using data from monitoring wells. Results showed that the average concentrations of groundwater phosphorus (P) decreased from pre-CW to post-CW but increased from pre-CP to post-CP. The average concentrations of groundwater total Kjeldahl nitrogen and ammonium ( $ {\mathrm{NH}}{_4^{ + }} $ ) increased from pre-CW (or CP) to post-CW (or CP), whereas the average concentrations of groundwater arsenic (As), chromium, nickel, and zinc (Zn) decreased from pre-CW to post-CW regardless of the well locations. Variations of groundwater cadmium, copper, and Zn concentrations were larger in pre-CP than in post-CP and had a tendency to decrease from pre-CP to post-CP. In general, the average concentrations of groundwater aluminum and manganese decreased and of groundwater calcium, iron, magnesium, and sodium increased from pre-CP to post-CP. The average values of water levels (depth from the ground surface), redox potential, and conductance decreased and of chloride and sulfate ( $ {\mathrm{SO}}{_4^{{ - 2}}} $ ) increased after the wetland and pond were constructed regardless of the well locations. Results further revealed that there were significant differences (α?=?0.05) between the pre- and post-CW (or CP) for redox potential, water level, and As. This study suggests that the CW–CP system had discernible effects on some of the shallow groundwater quality constituents. This information is very useful for fully estimating overall performance of stormwater treatment with the CW–CP system.  相似文献   
118.
氯代芳香化合物的KOW与对数拓扑指数和路径指数的相关性   总被引:3,自引:1,他引:2  
李良超  尹业高 《环境化学》1999,18(6):532-537
本文用1gKow表征氯代芳香化合物的生物降解能力,并分别以对数拓扑指数(LTI)和路径指数(PI)为自变量,建立了新的预测模型。结果表明,回归方程的预测值与实验值十分吻合,相关系数接近于1,平均标准偏差小于0.1。  相似文献   
119.
Viña A  Chen X  McConnell WJ  Liu W  Xu W  Ouyang Z  Zhang H  Liu J 《Ambio》2011,40(3):274-284
Conservation policies are increasing in response to human-induced ecosystem degradation, but little is known about their interplay with natural disasters. Through an analysis of satellite imagery and field data we evaluated the impacts of a devastating earthquake on forest recovery and avoided forest loss estimated to have been obtained by two of the largest conservation programs in the world. Results show that more than 10% of the forests in Wenchuan County, Sichuan province, China were immediately affected by the 2008 earthquake, offsetting some gains in forest cover observed since the enactment of the conservation programs. But without the enactment of these conservation programs, the combined effects of human disturbance and earthquake-induced landslides could have severely reduced the region’s forest cover. The continuation—and enhancement—of incentives for participation in conservation programs will be important for reducing the environmental impacts of the combined effects of human disturbance and natural hazards not only in the study area but also in many disaster-prone regions around the world.  相似文献   
120.
A dynamic fugacity model was developed to simulate the spatial and seasonal variations of PAHs in Haihe Plain, China. The calculated and measured concentrations exhibited good consistency in magnitude with deviations within a factor of 4 in air and 2 in soil. The spatial distributions of PAHs in air were mainly controlled by emission while the seasonal variations were dominated by emission and gas-particle partition. In soil, the spatial distributions of PAHs were controlled by the soil organic carbon content while the seasonal variations were insignificant. The severest soil contamination was observed in Shanxi and followed by the southwest of Hebei province. Transfer fluxes of total PAHs between air and soil were calculated. The spatial distribution of air-to-soil flux was closely related to the landcover while the soil-to-air flux changed with soil organic matter content. Monte Carlo simulation was done to evaluate the uncertainty of the estimated results in air.  相似文献   
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