利用人工基质无土栽培水蕹菜净化缫丝废水研究

在缫丝工业排放废水的水体中,无土栽培水蕹菜.经静态、动态和现场试验,水蕹菜在去除废水有机污染物的过程中,在较强的适应性.在6—7月间,水蕹菜在667m~2水面上10天的产量为625kg.应用水蕹菜无土栽培技术于缫丝废水资源化生态工程之中,既可以净化污水,又具有经济效益。认为该项技术可与黑麦草无土栽培技术衔接使用,形成全年运转的配套植物净化污水的方法.     

Endemic Arsenosis Caused by Indoor Combustion of High-As Coal in Guizhou Province, P.R. China

The arsenic (As) content of coal relating with mineralization of gold in Southwest Guizhou Province, China is up to 35,000 ppm. The coal is burned indoors in open pits for daily cooking and crop drying. As a result, arsenic is precipitated and concentrated in corn (5–20 ppm), chili (100–800 ppm) and other foods. Arsenic concentrations in the drinking water of high-As coal areas are lower than 50 ppb. The estimated main sources of As exposure in this area are from polluted food. Approximately, 3000 arsenosis patients were found by 1998, and more than 100,000 people from six counties were under the threat in China. This paper presents the major ingestion pathway of this type arsenosis and relative geochemistry of high-As coal. The project supported by National Natural Science Foundation of China (NSFC 40133010).     

废水中的丙溴磷气相色谱分析

试验了废水中的丙溴磷气相色谱分析方法。以大口径毛细管柱分离废水中的丙溴磷，分别采用氮磷检测器（NPD）和电子捕获检测器（ECD）检测，得到了良好的分离效果和较高的灵敏度，方法检测限为0．002mg/L(绝对检测量最低可达2pg,NPD)和0.0008mg/L(绝对检测量最低可达0．8pg,ECD)。该方法中，采用双柱双检测器，排除了误检和其他物质的干扰，保证了分析结果的可靠性。     

水平井钻磨管柱油管组合方式研究及下入安全性分析

基于钻磨管柱下入过程易造成遇卡事故,油田采用了2种线重油管的组合方式进行钻磨作业,提高了管柱的下入能力,但未能得到2种线重油管组合方式优选的可靠依据。为得到2种线重油管的最优组合方式,采用微元法对管柱单元在各井段的受力进行分析,建立钻磨管柱的下入载荷计算模型;采用编程对油田水平井进行实例计算,计算结果与实测结果对比显示模型平均误差在8.12%左右,验证了模型的正确性;基于下入载荷计算模型,进行了钻磨管柱组合特性研究及参数敏感性分析。结果表明:采用2种线重油管的组合方式能增大钻磨管柱下入能力,当大线重油管所占整个钻磨管柱的长度为井斜角70.8°左右的井深时,组合比例最优,不同的摩擦系数μ决定不同最优组合比例。     

Changes in visibility with PM2.5 composition and relative humidity at a background site in the Pearl River Delta region

In fall–winter, 2007–2013, visibility and light scattering coefficients(b sp) were measured along with PM_(2.5)mass concentrations and chemical compositions at a background site in the Pearl River Delta(PRD) region. The daily average visibility increased significantly(p 0.01) at a rate of 1.1 km/year, yet its median stabilized at ~13 km. No haze days occurred when the 24-hr mean PM_(2.5)mass concentration was below 75 μg/m~3. By multiple linear regression on the chemical budget of particle scattering coefficient(b sp), we obtained site-specific mass scattering efficiency(MSE) values of 6.5 ± 0.2, 2.6 ± 0.3, 2.4 ± 0.7 and 7.3 ± 1.2 m2/g,respectively, for organic matter(OM), ammonium sulfate(AS), ammonium nitrate(AN) and sea salt(SS). The reconstructed light extinction coefficient(b ext) based on the Interagency Monitoring of Protected Visual Environments(IMPROVE) algorithm with our site-specific MSE revealed that OM, AS, AN, SS and light-absorbing carbon(LAC) on average contributed 45.9% ± 1.6%,25.6% ± 1.2%, 12.0% ± 0.7%, 11.2% ± 0.9% and 5.4% ± 0.3% to light extinction, respectively.Averaged b ext displayed a significant reduction rate of 14.1/Mm·year(p 0.05); this rate would be 82% higher if it were not counteracted by increasing relative humidity(RH) and hygroscopic growth factor(f(RH)) at rates of 2.5% and 0.16/year-1(p 0.01), respectively, during the fall–winter, 2007–2013. This growth of RH and f(RH) partly offsets the positive effects of lowered AS in improving visibility, and aggravated the negative effects of increasing AN to impair visibility.     

发达国家和地区污染场地法律制度体系及启示

我国正在起草《土壤污染防治法》,这将为我国土壤、场地污染防治管理提供基本法律依据,并逐步建成完善的污染场地管理的法律制度体系。其中,监管体系、资金体系和责任体系是污染场地管理体系中的3大重要方面。美国、日本等发达国家和我国台湾地区在各自污染场地管理法律制度体系中,均规定了明确的监管主体,采用了多样化的监管手段,建立了可持续的污染场地专项基金,确定了明晰的责任判定和追究原则,为我国场地污染防治立法和制度设计中监管体系、资金体系和责任体系的建设提供了宝贵的借鉴。     

城市污水管网污染物沉积与冲刷释放规律研究

为明确城市污水管网中污染物沉积、冲刷释放及微生物降解作用对有机物去除的贡献,以管网中城市污水为研究对象,通过建立有沉积与无沉积的模拟管道,在首次冲刷的理论基础上得到管道污染物沉积释放计算模型,进而研究了不同流量下有机污染物的沉积与冲刷释放规律,并对不同流量下进出水的粒径分布及颗粒组成进行分析。结果表明,在管道6 h水力循环条件下,当流速为0.32 m/s时,污水中有机物变化以沉积贡献为主;当流速增加为管网最小设计流速0.6 m/s时,污染物沉积现象得到显著改善,冲刷释放效应增强;当流速进一步增加为0.9 m/s时,冲刷释放成为主要作用,生物降解作用微弱。     

Monitoring atmospheric nitrous oxide background concentrations at Zhongshan Station, east Antarctica

At present,continuous observation data for atmospheric nitrous oxide(N_2O) concentrations are still lacking,especially in east Antarctica.In this paper,nitrous oxide background concentrations were measured at Zhongshan Station(69°22′25″S,76°22′14″E),east Antarctica during the period of 2008–2012,and their interannual and seasonal characteristics were analyzed and discussed.The mean N_2O concentration was 321.9 n L/L with the range of 320.5–324.8 n L/L during the five years,and it has been increasing at a rate of 0.29% year-1.Atmospheric N_2O concentrations showed a strong seasonal fluctuation during these five years.The concentrations appeared to follow a downtrend from spring to autumn,and then increased in winter.Generally the highest concentrations occurred in spring.This trend was very similar to that observed at other global observation sites.The overall N_2O concentration at the selected global sites showed an increasing annual trend,and the mean N_2O concentration in the Northern Hemisphere was slightly higher than that in the Southern Hemisphere.Our result could be representative of atmospheric N_2O background levels at the global scale.This study provided valuable data for atmospheric N_2O concentrations in east Antarctica,which is important to study on the relationships between N2 O emissions and climate change.     

区域大气环境容量及其区域配置研究

以重庆市涪陵区为例,在了解区域大气环境功能区划及区域大气环境质量现状的前提下,采用A-P值法,对涪陵区十三五期间大气环境容量进行研究,并对辖区内的污染负荷进行预测,在此基础上,对大气污染总量控制指标进行分配.研究结果表明,在涪陵区化工园区的二氧化硫排放量已达到或超过总量控制指标,需要制定削减计划,新兴工业园区污染物排放量虽远小于总量控制指标,但根据城市发展规划需进行结构优化与合理布局.     

Towards Real‐Time Continental Scale Streamflow Simulation in Continuous and Discrete Space

The National Weather Service (NWS) forecasts floods at approximately 3,600 locations across the United States (U.S.). However, the river network, as defined by the 1:100,000 scale National Hydrography Dataset‐Plus (NHDPlus) dataset, consists of 2.7 million river segments. Through the National Flood Interoperability Experiment, a continental scale streamflow simulation and forecast system was implemented and continuously operated through the summer of 2015. This system leveraged the WRF‐Hydro framework, initialized on a 3‐km grid, the Routing Application for the Parallel Computation of Discharge river routing model, operating on the NHDPlus, and real‐time atmospheric forcing to continuously forecast streamflow. Although this system produced forecasts, this paper presents a study of the three‐month nowcast to demonstrate the capacity to seamlessly predict reach scale streamflow at the continental scale. In addition, this paper evaluates the impact of reservoirs, through a case study in Texas. Validation of the uncalibrated model using observed hourly streamflow at 5,701 U.S. Geological Survey gages shows 26% demonstrate PBias ≤ |25%|, 11% demonstrate Nash‐Sutcliffe Efficiency (NSE) ≥ 0.25, and 6% demonstrate both PBias ≤ |25%| and NSE ≥ 0.25. When evaluating the impact of reservoirs, the analysis shows when reservoirs are included, NSE ≥ 0.25 for 56% of the gages downstream while NSE ≥ 0.25 for 11% when they are not. The results presented here provide a benchmark for the evolving hydrology program within the NWS and supports their efforts to develop a reach scale flood forecasting system for the country.