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991.
The extraction of K+ and SiO2 from silicate minerals by Bacillus mucilaginosus in liquid culture was studied in incubation experiments. B. mucilaginosus was found to dissolve soil minerals and mica and simultaneously release K+ and SiO2 from the crystal lattices. In contrast, the bacterium did not dissolve feldspar. B. mucilaginosus also produced organic acids and polysaccharides during growth. The polysaccharides strongly adsorbed the organic acids and attached to the surface of the mineral, resulting in an area of high concentration of organic acids near the mineral. The polysaccharides also adsorbed SiO2 and this affected the equilibrium between the mineral and fluid phases and led to the reaction toward SiO2 and K+ solubilization. These two processes led to the decomposition of silicate minerals by the bacterium. 相似文献
992.
993.
采用臭氧氧化—包埋菌流化床生物处理组合工艺对煤气化废水进行深度处理。实验结果表明:当臭氧的质量浓度20 mg/L、臭氧进气流量1.5 L/min、臭氧通气时间30 min、包埋菌流化床水力停留时间24 h时,臭氧氧化工序的COD去除率达到30.0%~40.0%,总酚去除率达到100.0%;包埋菌流化床工序的COD去除率达到60.0%以上,氨氮的去除率大于95.0%;经组合工艺处理后,出水COD<60 mg/L,ρ(氨氮)<1.0 mg/L,ρ(总酚)未检出,色度小于50倍,达到GB8978—1996《污水综合排放标准》中的一级排放标准。 相似文献
994.
995.
Yuemin Yue Kelin Wang Bing Zhang Zhengchao Chen Quanjun Jiao Bo Liu Hongsong Chen 《Environmental monitoring and assessment》2010,160(1-4):157-168
Remote sensing of local environmental conditions is not accessible if substrates are covered with vegetation. This study explored the relationship between vegetation spectra and karst eco-geo-environmental conditions. Hyperspectral remote sensing techniques showed that there were significant differences between spectral features of vegetation mainly distributed in karst and non-karst regions, and combination of 1,300- to 2,500-nm reflectance and 400- to 680-nm first-derivative spectra could delineate karst and non-karst vegetation groups. Canonical correspondence analysis (CCA) successfully assessed to what extent the variation of vegetation spectral features can be explained by associated eco-geo-environmental variables, and it was found that soil moisture and calcium carbonate contents had the most significant effects on vegetation spectral features in karst region. Our study indicates that vegetation spectra is tightly linked to eco-geo-environmental conditions and CCA is an effective means of studying the relationship between vegetation spectral features and eco-geo-environmental variables. Employing a combination of spectral and spatial analysis, it is anticipated that hyperspectral imagery can be used in interpreting or mapping eco-geo-environmental conditions covered with vegetation in karst region. 相似文献
996.
Lidong Xue Yinhai Lang Aixia Liu Jie Liu 《Environmental monitoring and assessment》2010,163(1-4):57-65
Polycyclic aromatic hydrocarbons (PAHs) in coastal surface sediments from Rizhao offshore area were analyzed by gas chromatography–mass spectrometry. A chemical mass balance (CMB) model developed by the U.S. Environmental Protection Agency (EPA), CMB8.2, was used to apportion sources of PAHs. Seven possible sources, including coal residential, coal power plant, diesel engines exhaust, gasoline engines exhaust, coke oven, diesel oil leaks, and wood burning, were chosen as the major contributors for PAHs in coastal surface sediments. To establish the fingerprints of the seven sources, source profiles were collected from literatures. After including degradation factors, the modified model results indicate that diesel oil leaks, diesel engines exhaust, and coal burning were the three major sources of PAHs. The source contributions estimated by the EPA’s CMB8.2 model were 9.25%, 15.05%, and 75.70% for diesel oil leaks, diesel engines exhaust, and coal burning, respectively. 相似文献
997.
Wei-Bo Chen Wen-Cheng Liu Nobuaki Kimura Ming-Hsi Hsu 《Environmental monitoring and assessment》2010,168(1-4):407-428
A three-dimensional hydrodynamic model was created to study the Danshuei River estuarine system and adjacent coastal ocean in Taiwan. The model was verified using measurements of the time-series water surface elevation, tidal current, and salinity from 1999. We conclude that our model is consistent with these observations. Our particle-tracking model was also used to explore the transport of particles released from the Hsin-Hai Bridge, an area that is heavily polluted. The results suggest that it takes a much longer time for the estuary to be flushed out under low freshwater discharge conditions than with high freshwater discharge. We conclude that the northeast and southwest winds minimally impact particle dispersion in the estuary. The particles fail to settle to the bottom in the absence of density-induced circulation. Our model was also used to simulate the ocean outfall at the Bali. Our experimental results suggest that the tidal current dominates the particle trajectories and influences the transport properties in the absence of a wind stress condition. The particles tend to move northeast or southwest along the coast when northeast or southwest winds prevail. Our data suggest that wind-driven currents and tidal currents play important roles in water movement as linked with ocean outfall in the context of the Danshuei River. 相似文献
998.
Recently, environmental protection and regulations such as WEEE, ELV, and RoHS are rapidly emerging as an important issue for business to consider. The trend of swinging from end-of-pipe control to product design, green innovation, and even the establishment of image or brand has affected corporations in almost every corner in the world, and enlarged to the all modern global production network. Corporations must take proactive environmental strategies to response the challenges. This study adopts balanced scorecard structure and aim at automobile industries to understand the relationships of internal and external, financial and non-financial, and outcome and driving factors. Further relying on these relationships to draw the “map of environment strategy” to probe and understand the feasibility of environmental performance evaluation and environmental strategy control. 相似文献
999.
Investigation of heavy metals in sediments and Manila clams Ruditapes philippinarum
from Jiaozhou Bay, China 总被引:1,自引:0,他引:1
Xiaoyu Wang Yi Zhou Hongsheng Yang Qing Wang Shilin Liu 《Environmental monitoring and assessment》2010,170(1-4):631-643
Manila clams (Ruditapes philippinarum) and sediments were collected bimonthly during 2007 at five locations in Jiaozhou Bay near Qingdao, China, to determine heavy metal concentrations and to assess the validation of R. philippinarum as a metal biomonitor. Concentrations of heavy metals in clam soft tissues ranged between 0.75 and 3.31, 0.89 and 15.20, 5.70 and 26.03, 52.12 and 110.33, 10.30 and 72.34, 9.64 and 28.60, and 3.15 and 52.75 μg g???1 dry weight for Cd, Pb, Cu, Zn, Mn, Cr, and Ni, respectively. Most of the highest values occurred at the northeast bay and the lowest values occurred at the western part. Regarding seasonal variation, relatively high tissue metal concentrations were observed during October or December. A similar pattern was also found in habitat sediments. There was a strong correlation between the concentrations of Cd, Pb, Zn, Mn, Cr, and Ni in soft tissues and surrounding sediments. It is indicated that R. philippinarum could be used as a biomonitor for heavy metal contamination in Jiaozhou Bay. 相似文献
1000.
针对高碱度水库水源的某水厂残留铝超标问题,选取碱化度(B)与Alb含量不同的3种铝盐絮凝剂,研究不同投量与pH值下混凝效果与残留铝浓度水平。结果表明,碱化度和Alb含量显著影响混凝效果。DOC和浊度的去除率随着3种絮凝剂AlCl3(B=0)、PACl-1(B=1.2)、PACl-2(B=2.2)投量增大而升高。3种絮凝剂投量在1.5~2.0 mg/L(以铝计)范围内,总铝和溶解铝含量最低。对于该水厂自制的絮凝剂PACl-2,可通过降低絮凝剂碱化度,或将水的pH值降低至7~7.5之间,以此可以提高PACl-2混凝效果,而且可以降低出厂水残留铝浓度。考虑工程应用可行性,可优先考虑调整絮凝剂生产工艺。 相似文献