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171.
镇江市征润州水源地水质自动监测网络的建设及应用研究   总被引:1,自引:0,他引:1  
2012年2月3日,韩籍货轮苯酚泄漏造成镇江市自来水异味,造成市民的恐慌,严重影响着镇江市市民的正常生活,也引起镇江市市委市政府的高度重视。为了进一步实时动态监控水质变化状况,镇江市在征润州取水口上游新建两个水质自动站并结合原有的征润州水源水水质自动站,形成三点一线的长江沿岸的水质预警监测网络机制。在此着重介绍水源水水质自动监测系统的建设发展和应用,重视自动监测信息建设与数据共享问题,加强监控管理,质控管理体制和运行机制。  相似文献   
172.
本文通过以煤矸石为填充材料的复垦土壤上种植水稻的盆栽实验,研究在土壤复垦过程中煤矸石的填充方式和配比浓度对水稻籽粒和秸秆中重金属含量的影响。研究结果表明:在设定的煤矸石配比浓度范围内,水稻籽粒和秸秆中的重金属含量,都随煤矸石配比浓度的增加而增加,其中煤矸石配比浓度为40%时,增幅最大F元素在籽粒中的含量为0.921 mg/kg,是空白的1.12倍;在秸秆中的含量为9.064 mg/kg,是空白的4.19倍;煤矸石的两种填充方式下,水稻籽粒和秸秆中的重金属含量,大多呈现掺混式的大于垫底式的,其中煤矸石配比浓度为10%时,籽粒中差值最大的的F元素,含量相差了0.128 mg/kg,前者是后者的1.29倍;配比浓度为40%时,秸秆中差别最大的As元素,含量相差了0.352 mg/kg,掺混式的高于。垫底式的1.87倍。污染指数评价结果显示:籽粒中的重金属综合污染指数,皆小于1,未受到重金属污染,但在配比浓度为40%时,Hg的单项污染指数大于1,籽粒受到Hg的污染;秸秆的综合污染指数在1到3之间,重金属重污染程度严重,应对产出的秸秆妥善处理,以免对生态环境造成新的污染。  相似文献   
173.
• A high abundance of floating MPs was found in the southern South China Sea. • Transparent film and fiber were predominant in water and organisms, respectively. • 84.7% of floating MPs and 54.5% of MPs in vivo belonged to PP and PE. • Characteristics of MP in organisms were different from those of inshore ones. Surrounded by emerging markets with considerable plastic consumption, the South China Sea has been a focus area of microplastic research. A survey on the floating microplastics (>0.3 mm) and microplastics ingested by fish and mollusks was conducted around three remote islands here. Compared with the results from several previous studies, a high abundance of floating microplastics (with a median of 1.9 × 105 items/km2 or 0.7 items/m3) was observed, revealing another “hot spot” for microplastics. Polyolefin, especially polypropylene, was the main component. The diversity index and evenness index were calculated and evaluated based on the composition of microplastics. The characteristic peaks of Raman spectra concerning pigmented microplastics were provided. Transparent sheets/films were predominant in the water sample, which was quite different from a similar study in this sea area (8.9% for film), and only 16.4% of floating microplastics (>0.3 mm) were fibers/lines, implying that the main sources of floating microplastics (>0.3 mm) might be household/agricultural consumption activities. The transparent fiber/line was also dominant in organisms. It is suggested that the main sources of microplastics ingested by organisms might be both fabric fibers and fishing/aquaculture.  相似文献   
174.
● A database of municipal solid waste (MSW) generation in China was established. ● An accurate MSW generation prediction model (WGMod) was constructed. ● Key factors affecting MSW generation were identified. ● MSW trends generation in Beijing and Shenzhen in the near future are projected. Integrated management of municipal solid waste (MSW) is a major environmental challenge encountered by many countries. To support waste treatment/management and national macroeconomic policy development, it is essential to develop a prediction model. With this motivation, a database of MSW generation and feature variables covering 130 cities across China is constructed. Based on the database, advanced machine learning (gradient boost regression tree) algorithm is adopted to build the waste generation prediction model, i.e., WGMod. In the model development process, the main influencing factors on MSW generation are identified by weight analysis. The selected key influencing factors are annual precipitation, population density and annual mean temperature with the weights of 13%, 11% and 10%, respectively. The WGMod shows good performance with R2 = 0.939. Model prediction on MSW generation in Beijing and Shenzhen indicates that waste generation in Beijing would increase gradually in the next 3–5 years, while that in Shenzhen would grow rapidly in the next 3 years. The difference between the two is predominately driven by the different trends of population growth.  相似文献   
175.
自制深井曝气设备处理屠宰废水试验研究   总被引:2,自引:0,他引:2  
通过自制规模25L深井曝光设备屠中宰废水进行处理,试验结果表明,在最佳操作条件下,曝气8h,COD平均去除率可达82.835,BOD平均去除率可达81.09%,悬浮少平均去除率可达85.20%,动植物油平均去除率可达94.54%。出水水质可以达到肉类加工不工业水污染物排放标准GB13457-92的三组标准。而处理费用经估算仅为0.15/m^3,是一种高效低耗处理屠宰废水的较  相似文献   
176.
内蒙古西乌珠穆沁旗污水净化厂采用恒定水位运行的CWSBR工艺,经过接近两个月的污泥培养和试运行,出水水质达到城镇污水排放一级A标准。针对低C/N进水的实际状况,CWSBR系统通过采用单个周期多步进水及时序的可控调整,强化了系统的脱氮除磷性能。稳定运行阶段出水NH4+-N为3 mg/L以下,TN为15 mg/L以下,TP为0.5 mg/L以下。另外,该厂出水通过中水储池及升压提升,能够满足市政及工业回用需求,回用率达到80%以上。  相似文献   
177.
The great spatial and temporal variability in hydrological conditions and nitrogen(N)processing introduces large uncertainties to the identification of N sources and quantifying N cycles in plain river network regions. By combining isotopic data with chemical and hydrologic measurements, we determined the relative importance of N sources and biogeochemical N processes in the Taige River in the East Plain Region of China. The river was polluted more seriously by anthropogenic inputs in winter than in summer. Manure and urban sewage effluent were the main nitrate(NO-3) sources, with the nitrification of N-containing organic materials serving as another important source of NO-3. In the downstream, with minor variations in hydrological conditions, nitrification played a more important role than assimilation for the decreasing ammonium(NH+4-N) concentrations.The N isotopic enrichment factors(ε) during NH+4utilization ranged from- 13.88‰ in March to- 29.00‰ in July. The ratio of the increase in δ18O and δ15N of river NO-3in the downstream was 1.04 in January and 0.92 in March. This ratio indicated that NO-3assimilation by phytoplankton was responsible for the increasing δ15N and δ18O values of NO-3in winter. The relationships between δ15N of particulate organic nitrogen and isotopic compositions of dissolved inorganic nitrogen indicated that the phytoplankton in the Taige River probably utilized NH+4preferentially and mainly in summer, while in winter, NO-3assimilation by phytoplankton was dominant.  相似文献   
178.
Transport behaviors of graphene oxide nanoparticles (GONPs) in saturated porous media were examined as a function of the presence and concentration of anionic surfactant (SDBS) and non-ionic surfactant (Triton X-100) under different ionic strength (IS). The results showed that the GONPs were retained obviously in the sand columns at both IS of 50 and 200 mmol/L, and they were more mobile at lower IS. The presence and concentration of surfactants could enhance the GONP transport, particularly as observed at higher IS. It was interesting to see that the GONP transport was surfactant type dependent, and SDBS was more effective to facilitate GONP transport than Triton X-100 in our experimental conditions. The advection–dispersion–retention numerical modeling followed this trend and depicted the difference quantitatively. Derjaguin–Landau–Verwey–Overbeek (DLVO) interaction calculations also were performed to interpret these effects, indicating that secondary minimum deposition was critical in this study.  相似文献   
179.
参数分析是声发射技术应用中的重要环节之一,因为它直接关系到能否正确反映被检对象的物理状况。本文集多年检测的经验,提出了参数分析的几种方法以及参数分析中须注意的问题,力求通过参数分析方法来客观、合理地表征检测对象的物理状况。  相似文献   
180.
“十五”期间总站重点建设工作设想   总被引:1,自引:0,他引:1  
根据总站的职责 ,结合总站的现实条件 ,提出了“十五”期间总站的四大重点建设工作 ,一是加快总站现代化建设步伐 ,建成全国环境质量研究中心、全国环境监测数据现代化监控中心、具有国际水平的环境监测分析测试中心、全国生态环境监测遥感应用中心、全国环境监测仪器质量监督检验中心等五个中心 ,建设现代化的总站业务大楼 ;二是强化监测基础技术的系统研究 ;三是培养监测领域专家和学科带头人 ;四是提升总站的现代化管理水平。  相似文献   
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