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11.
以昆山为例,从监测点集成范围的选择、数据采集模式研究、数据传输模式研究、数据集成标准研究、数据应用展示样机等方面,对阳澄湖蓝藻综合监测监控模式进行研究,应用3G、物联网、云推送等新技术;制定《昆山市环境质量自动监测数据集成标准模式》和《昆山市环境质量自动监控通讯传输技术规范》;探索一条湖泊蓝藻综合监测监控的新思路和新模式。  相似文献   
12.
土壤中零价铁还原3-氯硝基苯的作用   总被引:3,自引:2,他引:1  
利用零价铁在常温常压下对土壤中的3-氯硝基苯的还原,对反应物和产物随时间的变化及反应的各个影响因素进行了研究。实验结果表明,零价铁能够有效地将3-氯硝基苯还原为3-氯苯胺,反应过程中没有检测到脱氯产物。其反应速率随铁粉用量、反应体系含水量的增加以及反应温度的升高而升高,随土壤初始pH值的升高而降低。在土壤中3-氯硝基苯含量约为2.5×10-6 mol/g,铁粉使用量为25 mg/g,反应体系中含水量为0.75 mL/g,pH值为6.8时,在恒温生化培养箱(25±1)℃反应5 h后,3-氯硝基苯的还原率达到92.75%。  相似文献   
13.
14.
A novel strain HZ5 was isolated from the activated sludge of a pesticide manufacturer in Hangzhou, which was capable of degrading beta-cypermethrin (beta-CP). Based on its physiological characteristics and analysis of 16S rDNA gene, strain HZ5 was identified as Azoarcus indigens, which was a new genus that can degrade beta-CP effectively. Strain HZ5 could degrade beta-CP over a wide range of temperature (20 to 40°C) and pH (5.5 to 9.0), and the optimal temperature and pH were 30°C and 7.0. The highest degradation rate was approximately 70% of 50 mg/L beta-CP within 144 h at pH 7.0 and 30°C in MSM. An additional carbon source could enhance the biodegradation of beta-CP. Studies on biodegradation of the beta-CP showed no significant enantioselectivity. During the process, two main intermediate metabolites were produced by strain HZ5 and determined as 3-phenoxybenzaldehyde and 3-phenoxybenzoic acid by gas chromatography-mass spectrometry (GC-MS) analysis. The results indicated that strain HZ5 may have potential application in bioremediation of beta-CP polluted environment.  相似文献   
15.
This study focused on the changes of reference evapotranspiration (ET0) and pan evaporation (ETpan) to study the impacts of climate change on the hydrological cycle in the Jinghe River catchment. Based on the Penman–Monteith equation, the ET0 was calculated. The temporal trend and spatial distribution of ET0 and Epan measured with a 20-cm pan were examined at the 14 stations during 1957–2005. The effects of meteorological factors on the variation of ET0 were determined by analyzing the trends in themselves with comparison between original climate and detrended climate scenarios and then their sensitivity to ET0. Both the ET0 and Epan showed remarkable decreasing trends from 1957 to 2005 and their decreasing rate was 40.9 and 17.7 mm per 10 years, respectively. Trend analysis of meteorological factors exhibited that the reduction in ET0 and ETpan was principally caused by both significant decreases in wind speed and sunshine hours. Furthermore, the decreasing trend of ET0 was mainly dominated by the significant decrease in wind speed with high sensitivity, to a less extent, by the decrease in net radiation. Although relative humidity is one of the most sensitive variables, its effect on ET0 was negligible because of its temporal constancy. The contribution of wind speed reduction to decreased ET0 has increased from 50 to 76.1%, but net radiation, by contrast, decreased from 50 to 23.9%.  相似文献   
16.
Modern dairies cause the accumulation of considerable quantity of dairy manure which is a potential hazard to the environment. Dairy manure can also act as a principal larval resource for many insects such as the black soldier fly, Hermetia illucens. The black soldier fly larvae (BSFL) are considered as a new biotechnology to convert dairy manure into biodiesel and sugar. BSFL are a common colonizer of large variety of decomposing organic material in temperate and tropical areas. Adults do not need to be fed, except to take water, and acquired enough nutrition during larval development for reproduction. Dairy manure treated by BSFL is an economical way in animal facilities. Grease could be extracted from BSFL by petroleum ether, and then be treated with a two-step method to produce biodiesel. The digested dairy manure was hydrolyzed into sugar. In this study, approximately 1248.6 g fresh dairy manure was converted into 273.4 g dry residue by 1200 BSFL in 21 days. Approximately 15.8 g of biodiesel was gained from 70.8 g dry BSFL, and 96.2 g sugar was obtained from the digested dairy manure. The residual dry BSFL after grease extraction can be used as protein feedstuff.  相似文献   
17.
Total Hg and methyl-Hg were evaluated in mine wastes, soils, water, and vegetations from the Wuchuan Hg-mining areas, Guizhou, China. Mine wastes contain high total Hg concentrations, ranging from 79 to 710 microg g(-1), and methyl-Hg from 0.32 to 3.9 ng g(-1). Total Hg in soil samples range from 0.33 to 320 microg g(-1) and methyl-Hg from 0.69 to 20 ng g(-1). Vegetations present a high average total Hg concentration of 260 ng g(-1), which greatly exceeds the maximum Hg concentration of 20 ng g(-1) recommended by the Chinese National Standard Agency for food sources. The rice samples contain elevated methyl-Hg concentrations, ranging from 4.2 to 18 ng g(-1). Stream water collected from Hg-mining areas is also contaminated, containing Hg as high as 360 ng l(-1), and methyl-Hg reaches up to 5.7 ng l(-1). Data indicate heavy Hg-contaminations and significant conversion of methyl-Hg in the study areas.  相似文献   
18.
采用聚合硅酸铝和聚合硅酸铁两种混凝剂,比较了将混凝剂直接投加到反应器中和对生物反应器出水再进行混凝沉淀2种工艺的除磷效果,并对2种混凝剂的除磷效果进行了比较.结果表明:对于聚合硅酸铝,没有生物协同作用;对于聚合硅酸铁,投加量在40 mg/L以下时具有生物协同作用,30 mg/L时协同作用最明显;而且聚合硅酸铁的除磷效果好于聚合硅酸铝.  相似文献   
19.
各种影响因子对电解法预处理医药废水的影响研究   总被引:2,自引:0,他引:2  
探讨了电解法预处理医药废水时停留时间、电解电压、废水初始浓度、温度和废水pH值等影响因子对去除色度、COD和提高废水可生化性等处理效果的影响,并考察了其应用于工业实际废水处理的可行性。实验结果表明:电解法更适合高浓度医药废水的处理,色度的去除率可达到90%以上;电解时间宜控制在40-60min;电解电压越高,废水COD和色度去除效果越好;在实验温度范围内,温度对色度和COD去除率的影响不大;废水pH值为7.5时电解效果最佳,工程运用宜控制在6—9之间。  相似文献   
20.
Road environments significantly affect in cabin concentration of particulate matter (PM). This study conducted measurements of in-vehicle and on-road concentrations of PM10, PM2.5, PM1, and particle number (PN) in size of 0.02–1 µm, under six ventilation settings in different urban road environments (tunnels, surface roads and elevated roads). Linear regression was then used to analyze the contributions of multiple predictor variables (including on-road concentrations, temperature, relative humidity, time of day, and ventilation settings) to measured variations. On-road measurements of PM2.5, PM1, and PN concentrations from the open surface roads were 5.5%, 3.7%, and 16% lower, respectively, than those measured in tunnels, but 7.6%, 7.1% and 24% higher, respectively, than those on elevated roads. The highest on-road PM10 concentration was observed on surface roads. The time series pattern of in-vehicle particle concentrations closely tracked the on-road concentrations outside of the car and exhibited a smoother profile. Irrespective of road environment, the average I/O ratio of particles was found to be the lowest when air conditioning was on with internal recirculation, the highest purification efficiency via ventilation was obtained by switching on external air recirculation and air conditioning. Statistical models showed that on-road concentration, temperature, and ventilation setting are common factors of significance that explained 58%-80%, 64%-97%, and 87%-98% of the variations in in-vehicle PM concentrations on surface roads, on elevated roads, and in tunnels, respectively.

Implications: Inside vehicles, both driver and passengers will be exposed to elevated particle concentrations. However, for in-vehicle particles, there has been no comprehensive comparative study of the three-dimensional traffic environment including tunnels surface roads and elevated roads. This study focuses on the analysis of the trends and main influencing factors of particle concentrations in different road environments. The results can provide suggestions for the driver's behavior, and provide data support for the environmental protection department to develop pollutant concentration limits within the vehicle.  相似文献   

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