银硫离子选择电极测定工业废水中的硫化物

本法用Ag/S离子选择电极测定废水中的硫化物,测定浓度范围0.1～1000.0mg/l,方法精密度为4.3％,回收率为P2.5％,检出限为0.1mg/l。大多数离子不干扰测定,该法简便快速,适用于例行监测。     

基于信息熵的省域内能源消费总量分配研究

能源消费总量控制是保障能源安全，积极应对气候变暖的重要手段；省域内能源消费量的合理分配，是落实国家能源消费总量控制的有效措施。提出能源消费总量分配应以公平为主、考虑区域发展权益的同时兼顾效率的原则，秉承“定基数，分增量”的思想，构建了基于信息熵的多因子混合加权分配模型，对目标年能源消费增量进行分配；选择了10个指标从经济水平、能耗水平、发展现状、产业结构及城市发展定位5个方面描述各地区的节能潜力及控制能耗量的责任，拟对能源消费总量在省内各市区的分配进行探索性研究。并以安徽省为例，对安徽省2015年能源消费总量分配到各市区进行了实证分析。结果显示，2015年安徽省17个市区能耗分配量增长率范围为1193%~5045%，能耗增幅的分配结果整体上受各市区人均GDP和人均能源消费量水平所支配，受单位工业增加值能耗和城市化率所调控     

Statistical Analysis of Air Pollutants and Meteorological Parameters in Afyon, Turkey

In this study, the relation between sulfur dioxide (SO₂) and particulate matter (PM) concentrations periodically measured in the city of Afyon’s atmosphere with meteorological factors such as precipitation, humidity, temperature, wind velocity, and inversion were investigated. The mean values of SO₂ and PM concentrations measured during the winter months of October–March 1990–1999 were correlated with the meteorological parameters of the same period. Simple and multiple linear regression analysis were utilized to evaluate the contribution of meteorological variables. The statistical results show that the pollutants, i.e., SO₂ and PM are dependent upon humidity, temperature, and inversion at the 1% significance level; while the dependence of both pollutants with temperature is negative when those of humidity and inversion are positive. Two models in which temperature and inversion are dependent with multiple variables are recommended for predicting the contribution of meteorological parameters on SO₂ and PM. In addition, the relationship between humidity, temperature, and inversion with pollutants is also determined using nonlinear (polynomial) models.     

A correlation between the fate and non-extractable residue formation of 14C-metalaxyl and enzymatic activities in soil

Extracellular, oxidative soil enzymes like monophenol oxidases and peroxidases play an important role in transformation of xenobiotics and the formation of organic matter in soil. Additionally, these enzymes may be involved in the formation of non-extractable residues (NERs) of xenobiotics during humification processes. To examine this correlation, the fate of the fungicide ¹⁴C metalaxyl in soil samples from Ultuna (Sweden) was studied. Using different soil sterilization techniques, it was possible to differentiate between free, immobilized, and abiotic (“pseudoenzyme”-like) oxidative activities. A correlation between the formation of metalaxyl NER and soil organic matter content, biotic activities, as well as extracellular phenoloxidase and peroxidase activities in the bulk soil and its particle size fractions was determined. Extracellular soil-bound enzymes were involved in NER formation (up to 8% of applied radioactivity after 92 days) of the fungicide independently from the presence of living microbes and different distributions of the NER in the soil humic subfractions.     

Simultaneous biological removal of endosulfan (alpha+beta) and nitrates from drinking waters using wheat straw as substrate

Nitrate and endosulfan (alpha+beta) removal was studied in an upflow biological denitrification reactor packed with wheat straw as carbon source and support particles for microorganisms. While almost complete nitrate elimination and between 65% and 70% endosulfan (alpha+beta) elimination occurred when the temperature was higher than 20 degrees C; below that value, nitrate removal efficiency decreased to about 10%. Nitrate, dissolved organic carbon (DOC), and endosulfan (alpha+beta) removal efficiencies decreased considerably at 1500 microg/l endosulfan concentration in the batch experiments. Although a high removal efficiency was observed for endosulfan (alpha+beta) and nitrate in the biological denitrification continuous reactor, the effluent water could not be used for drinking purpose because of the unacceptable levels of endosulfan (alpha+beta), colour and dissolved organic content. During the continuous study, 23.4% of the initial weight of wheat straw was lost and 24 g was consumed per gram of nitrogen removed. The results of the continuous study showed that 21.3% of the endosulfan removal was achieved by adsorption onto the wheat straw and 68.2% of the endosulfan removal occurred by biological activity and the remaining portion was detected in the effluent water.     

基于DEM的山区旱灾风险评价模型——以西南地区为例

旱灾研究中,地形导致的水热再分配容易造成地域间旱灾灾情的明显差异,因此地形因子对于旱灾风险的准确评价及灾情的客观评估至关重要。采用气象站点观测数据和DEM数据,通过模拟复杂地形影响下的下垫面真实水分情况,加入地形因子的影响,建立了以干旱致灾因子(水分条件)、孕灾环境(地形)、承灾体(农作物脆弱性曲线)综合的旱灾风险评价三度模型;并以地形复杂、旱灾多发的西南地区为例,编制了旱灾风险等级图,以期为客观评估旱灾灾情,有效开展区域旱灾风险防范提供科学依据。     

Development and verification of a toxicokinetic model of polychlorinated biphenyl elimination in persons working in a contaminated building

BACKGROUND: Polychlorinated biphenyls are toxic and slowly degrading substances that have been in widespread industrial use in the 1960s and 1970s. Despite a worldwide reduction, environmental exposure remains an issue; the assessment of an individual's level of exposure at a given time in retrospect requires valid toxicokinetic modeling of the different PCB congeners. OBJECTIVES: To develop and verify a toxicokinetic model of the in vivo-degradation of PCB 28 and 52 in adult humans. METHODS: The plasma concentrations of PCB congeners were measured in 583 persons working in a contaminated building for an average of 14.7+/-9.6 years. The values were adapted to a simple pharmacokinetic model (yt = y0 x (1 - e(-kt))); the steady state concentration y0 was estimated based on the median values of persons working exposed more than 10 years. RESULTS: The steady state concentration of PCB 28 was 0.10 microg/l, that of PCB 52 0.02 microg/l. The half-life of the congeners was estimated based on a logarithmic regression analysis according to the model mentioned above; it was 2.18 (95% CI: 1.91-2.54) years for PCB 28 and 3.95 (95% CI: 3.55-4.45) years for PCB 52, respectively. Stepwise elimination of persons with very long employment duration did not reduce the estimated half-life. CONCLUSIONS: The estimated half-life is higher than previously published data especially for PCB 52. Possible reasons and implications of this finding are discussed.     

Responses of earthworm to aluminum toxicity in latosol

Excess aluminum (Al) in soils due to acid rain leaching is toxic to water resources and harmful to soil organisms and plants. This study investigated adverse impacts of Al levels upon earthworms (Eisenia fetida) from the latosol (acidic red soil). Laboratory experiments were performed to examine the survival and avoidance of earthworms from high Al concentrations and investigate the response of earthworms upon Al toxicity at seven different Al concentrations that ranged from 0 to 300 mg kg^?1 over a 28-day period. Our study showed that the rate of the earthworm survival was 100 % within the first 7 days and decreased as time elapsed, especially for the Al concentrations at 200 and 300 mg kg^?1. A very good linear correlation existed between the earthworm avoidance and the soil Al concentration. There was no Al toxicity to earthworms with the Al concentration ≤50 mg kg^?1, and the toxicity started with the Al concentration ≥100 mg kg^?1. Low Al concentration (i.e., <50 mg kg^?1) enhanced the growth of the earthworms, while high Al concentration (>100 mg kg^?1) retarded the growth of the earthworms. The weight of earthworms and the uptake of Al by earthworms increased with the Al concentrations from 0 to 50 mg kg^?1 and decreased with the Al concentrations from 50 to 300 mg kg^?1. The protein content in the earthworms decreased with the Al concentrations from 0 to 100 mg kg^?1 and increased from 100 to 300 mg kg^?1. In contrast, the catalase (CAT) and superoxide dismutase (SOD) activities in the earthworms increased with the Al concentrations from 0 to 100 mg kg^?1 and decreased from 100 to 300 mg kg^?1. The highest CAT and SOD activities and lowest protein content were found at the Al concentration of 100 mg kg^?1. Results suggest that a high level of Al content in latosol was harmful to earthworms.     

Ni-Cu金属氧化物改性活性炭同时脱硫脱硝性能研究

采用浸渍法改性活性炭,分析了单组份Cu和双组份Cu-Ni金属氧化物对活性炭改性后同时脱硫脱硝性能的影响。实验中用于改性的产物分为两组:x%CuO-AC,5%NiO-x%CuO/AC(x%表示负载的物质占总物质的百分比),在不同温度下测试了活性。结果表明,CuO单独改性活性炭可以提高120℃下活性炭同时脱硫脱硝性能,且6%CuO/AC效果最好;在CuO/AC上负载5%的NiO,可以进一步提高120℃下活性炭同时脱硫脱硝性能,且5%NiO-2%CuO/AC的效果最好。     

水和废水中阴离子表面活性剂测定干扰因素试验研究

对二氮杂菲萃取分光光度法测定水和废水中阴离子表面活性剂的主要干扰因素进行了试验研究.设计了温度过低、浑浊带色和混溶乳化3种干扰试验方案,探讨了各干扰因素在不同工况下的试验结果、影响程度及消除措施.提出温度过低须在测定前提高环境温度,以确保显色反应完全;浑浊带色须在测定中采用色(浊)度校正法消除干扰;混溶乳化可在测定中利...