Formulation of criteria for pollution control on cement products produced from solid wastes in China

The process of producing cement products from solid waste can increase the level of pollutants in the cement products. Therefore, it is very important to establish a pollution control standard for cement products to protect the environment and human health. This paper presents acceptance limits for the availability of heavy metals in cement products which have been produced from solid wastes and explains how the limits have been calculated. The approach and method used to formulate these criteria were based on EN 12920. The typical exposure scenarios used in this paper involve concrete being used for drinking water supply pipelines and concrete pavements and are based on an analysis of typical applications of cement in China, and the potential for contact with water. The parameters of a tank test which was based on NEN 7375 were set in accordance with the environmental conditions of typical scenarios in China. Mechanisms controlling the release of heavy metals in concrete and a model for that release were obtained using the leaching test. Finally, based on acceptance criteria for drinking water and groundwater quality in China, limit values for the availability of heavy metals in concrete were calculated.     

基于熵技术的尾矿库安全模糊综合评价体系研究

在以往对尾矿库安全评价时,常常只对尾矿库的地质情况、坝体结构、防洪能力和坝体稳定性等进行安全度计算,然后评价尾矿库安全性,但都未能全面综合地判定尾矿库的安全运行状况。针对尾矿库安全评价具有定性指标多、定量指标少、评价主观性过强、客观性偏弱等特点,建立涵盖坝体稳定性、排洪安全性、输送及排放安全性、监测可靠性、管理全面性为一级指标的尾矿库安全现状评价指标体系。利用信息论中熵的概念计算客观权重的方法,避免人为主观的影响,提出尾矿库安全模糊综合评价模型。应用该模型对陕西省某尾矿库的安全现状进行评价,根据评价结果并结合评价指标的权重探索尾矿库存在的安全隐患,为进一步整改提供理论依据,具有一定的使用价值。     

改造现有工艺回收地面计量天然气

为解决牙哈作业区A区块3口井在见水后含水上升较快、单井产液量增加、现有装置处理能力不足,导致A区块所有生产井不能全部进站的问题,同时为提高最终采收率,需要延长见水时间,见水后控制含水的上升趋势。这就要求掌握含水井的生产动态,而现有装置无法对单井的含水进行计量,塔里木油田公司牙哈作业区A区块建造集中试采装置,文章介绍了改造前后的工艺流程及改造效果。     

沙漠油田开发生态环境保护的实践

文章阐述了地处沙漠腹地的石西油田在开发建设过程中开展环境保护工作的具体做法,从加强组织领导、制定并不断完善环保规章制度、加大科技投入等方面分析总结了在沙漠油田中开展环境保护的管理经验,通过加强井场作业、油气集输、建设用地管理、植物种植管理方面的措施,阐述了在沙漠油田开发建设中创建绿色油气田活动所取得的成绩。     

一株耐铜不动杆菌USTB-F的富集特性

采用浓度梯度筛选的方法,从铜污染土壤中分离筛选到一株耐受铜的菌株USTB-F,最高耐受浓度为560mg·L-1.通过生理生化实验和16SrDNA序列分析鉴定属于不动杆菌属,命名为Acinetobacter sp.USTB-F.用单因素方法得到USTB-F的最适生长条件为:T=30℃;pH=6.0;NaCl浓度为0.3%...     

Pressure cookers or pressure valves: Do roads lead to deforestation in China?

The effect of roads on forests is ambiguous. Many studies conclude that building and upgrading roads increases pressure on forests but some find that new and better roads may reduce the rate of deforestation. In this paper we use satellite remote sensing images of forest cover in Jiangxi Province, China, to test whether the existence and the size of roads (ranging from expressways to tertiary roads) in 1995 affected the level of forest cover in 2000 or the rate of change between 1995 and 2000. To account for road access for each of our 1 km² (“pixel”) units of forest cover we measure whether or not and what type of roads penetrate the “watershed” in which the pixel lies. These watersheds allow more plausible measures of accessibility than do traditional “crowfly” distance measures that ignore topography. To account for possible confounding we also use 12 additional covariates: geographic and climatic variables (e.g., elevation, slope, rainfall, temperature, soil properties); demographic and economic variables (e.g., local population and GDP per square kilometer); and distance variables (e.g., distance to the nearest provincial capital). Although simple univariate OLS regressions show that forest levels are lower and deforestation rates higher either when there is a road, or when there is a higher quality road, these results are not robust. Controlling for all of the covariates and also using recently developed covariate matching techniques to estimate treatment effects, we find that roads in China’s Jiangxi Province can most safely be described as having no impact on the level of forests and no impact on the rate of deforestation.     

变化环境下北江下游年径流量的加权马尔可夫链预测

在气候变化和人类活动的影响下,西北江的水文环境发生了重大变化,导致北江下游的来水条件发生变化。采用斯波曼检验（Spearman’s rho test）和Mann-kendall法系统地分析了北江下游的年径流量的变化趋势和变异情况,在此基础上建立了北江下游变化环境下年径流量的加权马尔可夫链预测模型。结果表明：西北江近50年来的大规模联围筑闸、大规模无序采掘河床泥沙等剧烈的人类活动,导致北江下游三水水文站年径流量在1990年左右发生了变异;所建立的加权马尔可夫链预测结果表明,从变异后的序列中统计出来的状态＂转移概率＂矩阵,能准确地反映出环境变化后年径流量之间的关系,所建立的加权马尔可夫链法预测变化环境下的年径流量是可行的,预测效果也比较好;按文章确定的分级标准,依现有的资料信息推断,环境发生变化后,在未来长期过程中,北江下游出现平水年的机会最大,但年际间的丰枯波动概率也不小。这一结果值得水资源管理部门注意。     

环介导等温扩增技术(LAMP)检测人星状病毒方法的建立及其在再生水检测中的应用

为快速高效地检测人星状病毒,建立了一种新的试验方法——环介导等温扩增技术(loop-mediated isothermal amplification technology,LAMP),并对人星状病毒LAMP反应条件进行了优化.结果表明,镁离子终浓度为4 mmol·L-1、甜菜碱终浓度为1mol.L-1的25μL体系下...     

Aerosol size distributions in urban Jinan: Seasonal characteristics and variations between weekdays and weekends in a heavily polluted atmosphere

Aerosol size distributions, trace gas, and PM(2.5) concentrations have been measured in urban Jinan, China, over 6 months in 2007 and 2008, covering spring, summer, fall, and winter time periods. Number concentrations of particles (10-2,500 nm) were 16,200, 13,900, 11,200, and 21,600 cm(?-3) in spring, summer, fall, and winter, respectively. Compared with other urban studies, Jinan has higher number concentrations of accumulation-mode particles (100-500 nm) and particles (10-2,500 nm), but lower concentrations of ultrafine particles (10-100 nm). The number, surface and volume concentrations, and size distributions of particles showed obvious seasonal variation and are also influenced by traffic emissions. Through correlation analysis, traffic emissions are proposed to be a more important contributor to Atkien-mode and accumulation-mode particles than coal firing. Around midday, the presence of nanoparticles and new particle formation is limited to pre-existing particles from traffic emissions and the mass transport of particles from suburban and rural areas. Compared with other studies in urban areas of Europe and the USA, the variation of particle number concentration and related gas concentration in Jinan between weekdays and weekends is smaller and the reasons has been deduced.     

Atmospheric-particulates-bound mercury Hg(p) study at five characteristic sampling sites in Taiwan

The main purpose for this study is to observe the seasonal and month variations for particulates-bound mercury Hg(p) in total suspended particulates (TSP) concentration, dry deposition at five characteristic sampling sites during years of 2009-2010 in central Taiwan. The results show that the highest and lowest monthly average particulates-bound mercury Hg(p) concentrations in TSP were occurred in Dec. and Oct. at Gao-mei (wetland), Chang-hua (downtown) and He-mei (residential) sampling site. In addition, the results show that the highest and lowest monthly average particulates-bound mercury Hg(p) dry deposition was occurred in Feb. and Oct. at Quan-xing (industrial) sampling site. This study reflected that the mean highest particulates-bound mercury Hg(p) concentrations in TSP and mean highest particulates-bound mercury Hg(p) dry deposition were occurred at Gao-mei (wetland) and Quan-xing (industrial). However, the mean lowest particulates-bound mercury Hg(p) concentrations in TSP and mean lowest particulates-bound mercury Hg(p) dry deposition were also occurred at Gao-mei (wetland). Regarding seasonal variation, the order of mean-particulates-bound mercury Hg(p) concentrations in TSP in winter and spring were Gao-mei (wetland) > Quan-xing (industrial) > Bei-shi (suburban/coastal) > Chang-hua (downtown) > He-mei (residential). Finally, the order of mean-particulates-bound mercury Hg(p) dry deposition in fall, spring and summer were Quan-xing (industrial) > Bei-shi (suburban/coastal) > Chang-hua (downtown) > He-mei (residential) > Gao-mei (wetland).