ABR反应器的两种快速启动方法对比

ABR反应器的启动是ABR反应器能否高效稳定运行的关键,其影响因素很多。为了更好地实现ABR反应器的启动,提出了通过2种不同启动方法的对比,即1^#反应器采用好氧预挂膜的方法,2^#反应器采用低负荷启动法,得出的结论为,好氧预挂膜启动法的启动时间短,COD去除率高,出水pH稳定,颗粒状污泥生长情况较好,是一种可推广的启动方法。     

氮掺杂氧化钛的简易制备及可见光催化活性的研究

为开发对可见光响应的催化剂,以尿素为氮掺杂剂,采用简易溶胶-凝胶法制备氮掺杂氧化钛,并以2,4-DCP的降解检验其光催化活性。XRD、BET、XPS和UV-Vis漫反射光谱分析表明,随着氮/钛原子比（N/Ti)的增大,各催化剂晶粒尺寸减小,比表面积增大,锐钛矿相向金红石相的转变得到抑制,除0#样品出现金红石相外,其他催化剂均只出现锐钛矿相;掺入催化剂的N位于晶格O位点和晶格间隙,替代N和间隙N掺杂使催化剂的光吸收发生明显的红移。荧光光谱分析表明,当N/Ti在0～6范围内增加时,反应体系中·OH自由基的产生速率增加,当N/Ti增大至8时,速率则下降。相似的规律也表现在氮掺杂量对光催化活性的影响。适量氮掺杂能增强氧化钛的可见光催化活性,该改性催化剂可用于有机污染物的太阳光激催化降解。     

Regional impervious surface estimation: an urban heat island application

This paper describes a GIS-based estimation method that can be used to forecast future amounts of impervious surface as a mitigation measure for urban heat island effect in a metropolitan region. The method is unique because it employs a regression model that links the existing amount of impervious surface to population and employment at the census tract level. This approach provides a means to forecast future amounts of impervious surface based on projected population and employment. The method also includes a detailed analysis of high-resolution aerial photography to divide impervious surfaces into different categories. Subdividing impervious surfaces is necessary to evaluate potential urban heat island mitigation policies for different types of impervious surface. The analysis here shows that the impervious surface in the metropolitan Atlanta region will increase to 2638 km2 2. “The Albedo is defined as the hemispherical reflectivity averaged over the solar spectrum. A perfect reflector has a = 1, and a perfect absorber has a = 0” (Pomerantz et al. 1999 Pomerantz, M. 1999. Reflective surfaces for cooler buildings and cities. Philosophical magazine B, 79: 1457–1476. [Taylor & Francis Online], [Web of Science ®] [Google Scholar], p. 1458). View all notes in 2030, an increase of 45% from 2000. The most common type of impervious surface is dark-coloured pavement. Within this study area, the analyses showed that two-thirds of impervious surfaces are dark. Replacing dark pavement with light pavement materials, therefore, represents an important opportunity to mitigate the urban heat island effect in the Atlanta region.     

固相萃取-高效液相色谱法测定地表水中的溴氰菊酯

建立了固相萃取-高效液相色谱-二极管阵列扫描测定地表水中溴氰菊酯的方法。溴氰菊酯经C18小柱富集,用6．0mL二氯甲影丙酮（1：1,v／v）洗脱,氮吹转换溶剂为甲醇并定容至1mL后由高效液相色谱仪进行分析,检测波长为270hm,通过保留时间与特征紫外吸收图谱定性,外标法定量。方法检出限1．0ug／L;线性范围1．0～97．0ug,／L,／相关系数0．9999;相对标准偏差7．7％-17．5％（n=6）;回收率在90．6％～111．9％。方法简单,快速,经济环保。     

FS—IV^＋流动注射仪测定地表水中氨氮

铵与碱性酚和次氯酸钠反应生成靛蓝化合物,其色度与铵的浓度成正比,亚硝基氰化物使蓝色增强,在660nm处测量吸光度值;采用Flow Solution-IV^＋（FS-IV^＋）流动注射仪测定地表水中氨氮,检测范围0～10．00mg／L,检出限0．008mg／L,分析速率51个样S／h;对方法精密度、准确度、加标回收进行了实验,结果令人满意。该方法具有自动进样、分析速率快、试剂耗量低等优点,可应用于大批量常规地表水分析。     

负载型TiO2薄膜光催化剂降解亚甲基蓝

采用溶胶-凝胶法制备了玻璃负载的TiO2薄膜光催化剂,研究了该催化剂对亚甲基蓝溶液的光催化降解,考察了反应时间、水样的初始浓度、溶液的pH等对光催化降解效果的影响。     

河北省地表水环境污染特征及分析

河北省1998年-2005年的水环境质量监测数据分析表明：河北省地表水污染恶化趋势基本得到遏制,但部分地区水污染矛盾仍很突出;水体总体污染减轻,但氨氮污染有加重趋势;主要湖（库）水水质稳定,但普遍呈不同程度的富营养化。在此基础上,分析了地表水污染的原因,并提出了河北省改善地表水环境污染的对策与措施。     

MODIS Biophysical States and NEXRAD Precipitation in a Statistical Evaluation of Antecedent Moisture Condition and Streamflow1

Abstract: The potential of remotely sensed time series of biophysical states of landscape to characterize soil moisture condition antecedent to radar estimates of precipitation is assessed in a statistical prediction model of streamflow in a 1,420 km² watershed in south‐central Texas, Moderate Resolution Imaging Spectroradiometer (MODIS) time series biophysical products offer significant opportunities to characterize and quantify hydrologic state variables such as land surface temperature (LST) and vegetation state and status. Together with Next Generation Weather Radar (NEXRAD) precipitation estimates for the period 2002 through 2005, 16 raw and deseasoned time series of LST (day and night), vegetation indices, infrared reflectances, and water stress indices were linearly regressed against observed watershed streamflow on an eight‐day aggregated time period. Time offsets of 0 (synchronous with streamflow event), 8, and 16 days (leading streamflow event) were assessed for each of the 16 parameters to evaluate antecedent effects. The model results indicated a reasonable correlation (r² = 0.67) when precipitation, daytime LST advanced 16 days, and a deseasoned moisture stress index were regressed against log‐transformed streamflow. The estimation model was applied to a validation period from January 2006 through March 2007, a period of 12 months of regional drought and base‐flow conditions followed by three months of above normal rainfall and a flood event. The model resulted in a Nash‐Sutcliffe estimation efficiency (E) of 0.45 for flow series (in log‐space) for the full 15‐month period, ?0.03 for the 2006 drought condition period, and 0.87 for the 2007 wet condition period. The overall model had a relative volume error of ?32%. The contribution of parameter uncertainties to model discrepancy was evaluated.     

金竹山土朱煤矿开采地表沉降规律与灰色预测模型研究

针对金竹山矿业公司土朱煤矿煤层赋存条件,依据采动理论的裂缝垂直分带模型,分析地表沉降和塌陷的机理;提出在采煤活动阶段应进行地表实际位移观测,经数据处理后得到地面沉降曲线,以确保地面人类活动的安全;在采煤活动后阶段则实施灰色预测地面沉降,即通过采煤活动阶段的地表实际观测数据为历史原始数据序列,建立灰色Logistic模型;并对采煤活动后阶段的地面沉降进行预测。精度检验表明:灰色Logistic模型预测精度高,利用该模型预测地面沉降可减少地面沉降监测经费和实时提供预警信息,以确保开采区域内人们生命财产安全。