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721.
The effects of different electrode on Solanum nigrum L.seed germination were determined.The result showe d that germination percentage(GP) of seeds in treatment T2(titanium electrode) was 26.6% higher than in control(CK,without electric field).High potassium and calcium concentrations were beneficial for seed enzymatic activity in treatment T2,which could partly explain the increase in GP.Cd accumulation(μg/pot) in S.nigrum treated with any electric field was significantly higher(p<0.05) than...  相似文献   
722.
Qin  Qilin  Xu  Xijin  Dai  Qingyuan  Ye  Kai  Wang  Chenyang  Huo  Xia 《Environmental geochemistry and health》2019,41(1):93-123
Environmental Geochemistry and Health - This paper reviews the concentrations of persistent organic pollutants (POPs) in atmosphere of an electronic waste (e-waste) recycling town, Guiyu, in...  相似文献   
723.
Environmental Science and Pollution Research - The fate and transport of polychlorinated biphenyls (PCBs), a class of persistent organic compounds, in soils was markedly affected by their...  相似文献   
724.
725.
Alkylphenols (APs), the breakdown products of alkylphenol polyethoxylates that are widely used as surfactants, have been proven to exert estrogenic effects. With industrial development, higher concentrations of APs are discharged into aquatic environments. Nonylphenol (NP), the most noxious AP, is included in the blacklist of several countries. The toxicity of NP to the alga Cyclotella caspia and the biodegradation of NP by C. caspia were studied in the laboratory. The median effective concentration at 96 hr (96 hr EC50 ) of NP for C. caspia was found to be 0.18 mg/L. Five toxicity and three degradation indices were selected for toxicity and biodegradation experiments, respectively, in five or three concentrations of NP set by the 96 hr EC50 of NP. The algal growth rate and chlorophyll a contents decreased as NP concentration increased. The main manifestations of morphological deformity of the cells included volume expansion and the presence of cytoplasmic inclusions (lipid droplets). The abnormality rate of the cells increased with NP concentration and time, and was 100% at 0.22 and 0.26 mg/L of NP after 192 hr of culture. Superoxide dismutase activity initially increased and then declined at a higher NP toxicity of greater than 0.18 mg/L. After 192 hr of culture, the biodegradation rates of NP by C. caspia with initial concentrations of 0.14, 0.18, and 0.22 mg/L were 37.7%, 31.7%, and 6.5%, respectively. The kinetic equation of C. caspia biodegradation on NP was correlated with algal growth rate and initial NP concentration.  相似文献   
726.
以海尔《环境报告书》和《年度报告》为主要数据来源,调查了海尔青岛本部2007年一2010年主要家电产量和CO2排放量,用灰色关联模型对电冰箱、洗衣机和空调器产量与C02排放量进行了关联度分析。结果显示,这三种家电产量与CO2排放量的关联度分别是0.44、0.65和0.60,显示洗衣机产量是影响CO2排放量的最主要因素,其后依次是空调器和电冰箱。结果可为家电生产商优化产品生产策略、控制CO2排放提供辅助。讨论了方法的局限和进一步的研究方向。  相似文献   
727.
根据指标构建的科学性、系统性等原则,构建了城市群经济与环境协调发展指标体系,利用因子分析法测算出经济与环境综合发展水平,在此基础上,建立了经济与环境协调发展评价模型,并以秦唐沧城市群为例进行了实证分析。结果表明:2002年-2011年间秦皇岛经济与环境协调发展度高于唐山和沧州,协调发展类型由初步协调向良好协调转变;唐山经济与环境协调发展度呈波浪式上升,由中度失调向中等协调转变;沧州经济与环境协调发展度处于末位,由中度失调向中等协调转变。  相似文献   
728.
东三旗台Sacks体应变干扰分析与震例研究   总被引:4,自引:0,他引:4  
本文对北京市昌平区东三旗台Sacks体应变观测值与固体潮、气压、水位、降雨关系进行了初步分析。通过干扰因素分析,为提高地震预报的准确性提供了参考依据。同时,进行了有关震例研究,希望通过总结震例,为今后利用Sacks体应变观测探索地震预报实践建立科学的分析处理方法。  相似文献   
729.
Artificial Neural Network (ANN) is a flexible and popular tool for predicting the non-linear behavior in the environmental system. Here, the feed-forward ANN model was used to investigate the relationship among the land use, fertilizer, and hydrometerological conditions in 59 river basins over Japan and then applied to estimate the monthly river total nitrogen concentration (TNC). It was shown by the sensitivity analysis, that precipitation, temperature, river discharge, forest area and urban area have high relationships with TNC. The ANN structure having eight inputs and one hidden layer with seven nodes gives the best estimate of TNC. The 1:1 scatter plots of predicted versus measured TNC were closely aligned and provided coefficients of errors of 0.98 and 0.93 for ANNs calibration and validation, respectively. From the results obtained, the ANN model gave satisfactory predictions of stream TNC and appears to be a useful tool for prediction of TNC in Japanese streams. It indicates that the ANN model was able to provide accurate estimates of nitrogen concentration in streams. Its application to such environmental data will encourage further studies on prediction of stream TNC in ungauged rivers and provide a useful tool for water resource and environment managers to obtain a quick preliminary assessment of TNC variations.  相似文献   
730.
根据2004—2009年大气中SO2污染物的监测数据,通过灰色GM(1,1)模型预测了未来6年秦皇岛市大气中SO2的变化趋势。结果显示,灰色系统GM(1,1)模型合理,精度较高,相对误差为-1.875%~1.228%,与环保部门公布的数据吻合程度较好。  相似文献   
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