乌鲁木齐市大气污染时空分布规律研究

为掌握乌鲁木齐市大气污染时空分布规律，利用近年乌鲁木齐市大气污染物的浓度最新资料，详尽分析了其空气质量的年际变化和空间分布特征。统计了2008年各污染物日、月变化规律。结果表明，近年乌鲁木齐市城区大气污染物质量浓度具有明显时空分布规律，即大气污染物质量浓度冬春季大于夏秋季，PM10和SO2浓度夜间大于白天。在空间分布上，PM10和SO2南部区域最高，中部次之，市区北部最轻，NO2则呈现出由北向南逐渐升高的分布特征。     

基于GM（1，N）灰模型预测企业主动性安全投入

本文基于GM（1，N）灰模型对企业主动性安全投入总量进行预测，研究把企业安全整体情况或整体表现作为一个“灰系统”对待时，依据该系统的特征量，来对企业主动性安全投入进行预测，为我国企业进行安全投入时提供决策依据。     

中国两性生殖卤虫形态特征的数值分类研究

对中国两性生殖卤虫１２个品系的１０个品系形态特征进行了聚类分析和主成分分析，并与Ａ．ｕｒｍｉａｎａ进行了比较研究．研究结果表明，Ａ．ｕｒｍｉａｎａ和中国两性生殖卤虫各品系明显可分为２个类群，证明中国各两性生殖卤虫品系均属于Ａ．ｓｉｎｉｃａ．而Ａ．ｓｉｎｉｃａ不属于Ａ．ｕｒｍｉａｎａ．在中国两性生殖卤虫各品系中ＮＬ、ＨＪＱ、ＳＢ可分为另一类群，显示可能存在种下分类阶元．本文所选取的形态特征是稳定的，可做为卤虫品系形态特征数值分类的重要依据．     

New best estimates for radionuclide solid–liquid distribution coefficients in soils,Part 1: radiostrontium and radiocaesium

Best estimates for the solid-liquid distribution coefficients (K_d) of radiostrontium and radiocaesium for various soil types, were derived from geometric means (GM) calculated from grouping soils by texture and organic matter content, and also using soil cofactors governing soil–radionuclide interaction. The K_d (Sr) GM for Sand, Loam, Clay and Organic groups were similar, although the value for the Sand group was significantly lower. The Sr cofactor approach, based on the ratios of cation exchange capacity (CEC) to Ca and Mg concentrations in the soil solution, leads to K_d (Sr) GM with a lower variability, from which best estimates could be proposed. The K_d (Cs) GM for Sand and Organic groups differed, although similar values were obtained for Loam and Clay groups. Grouping the K_d (Cs) according to the Radiocaesium Interception Potential (RIP) and the RIP divided by the K concentration in the soil solution also allows to suggest K_d (Cs) best estimates with a lower variability.     

Phosphorus fractions and adsorption characteristics of floodplain sediments in the lower reaches of the Hanjiang River, China

The phosphorus fractions and adsorption characteristics of seven floodplain sediment samples collected in the lower reaches of China’s Hanjiang River were studied. Most phosphorus fractions showed a marked downstream increase in response to point-source inputs from urban areas. Total phosphorus (TP) contents in the sediments ranged from 603.68 to 945.25 mg.kg⁻¹. Inorganic phosphorus (IP) was the major component of TP, and calcium-bound phosphorus (Ca–P) was the major fraction of IP. The distribution characteristics of the phosphorus contents were affected by sediment grain size and hydrodynamic conditions. The maximum phosphorus adsorption capacities (Q _max) and the half-saturation concentration (k) were obtained using an improved Langmuir model. Native adsorbed exchangeable phosphorus content (w _NAP) and the zero-equilibrium phosphorus concentration value (c _EPC0) were subsequently calculated. The effects of sediment grain size, temperature, and disturbance on the phosphorus adsorption isotherms were also studied. The results showed that phosphorus adsorption on floodplain sediments was primarily chemisorption; the particle concentration effect played a more important role at a disturbance intensity of 150 r.min⁻¹ (on a shaker table) than at 100 r.min⁻¹.     

Monitoring of Coliforms and chlorine residual in water distribution network of Rawalpindi, Pakistan

The present study was undertaken to examine the drinking water quality of Rawal Treatment Plant, Rawalpindi and its distribution network by collecting samples from eight different locations. The aim was to determine potential relationship between the presence of microorganisms and chlorine residual in the distribution network. Quantification of chlorine residual, turbidity, standard plate count (SPC), fecal and total coliforms by Most Probable Number (MPN) was performed. Three different forms of chlorine were measured at each sampling station such as free chlorine, residual chlorine, chloramines and total chlorine residual. A critical evaluation of data presented indicated that pH generally ranged from 7.02–7.30; turbidity varied from 0.34–2.79 NTU; conductivity fluctuated from 359–374 μS/cm; and TDS values were found to be ranging between 180–187 mg/l. Station # 7 was found to be most contaminated. The value of total chlorine was found to be 0.86 to1.7 mg/l at Station # 3 and 6, respectively. Highest standard plate count was 62 CFU/ml at Station # 7. Total coliforms were less than 1.1 MPN/100 ml at almost most of the stations except at Station # 3 where it was found to be greater than 23.0 MPN /100 ml. Overall aim of this study is to create awareness about contamination of drinking water in the water distribution networks and to make recommendations to provincial agencies such as EPA, CDA and WASA that regular monitoring should be carried out to ensure that the chlorine residual is available at consumer end.     

U(VI) adsorption on aquifer sediments at the Hanford Site

Aquifer sediments collected via split-spoon sampling in two new groundwater wells in the 200-UP-1 operable unit at the Hanford Site were characterized and showed typical Ringold Unit E Formation properties dominated by gravel and sand. High iron-oxide content in Fe oxide/clay coatings caused the highest U(VI) adsorption as quantified by batch K(d) values, indicating iron oxides are the key solid adsorbent in the 200-UP-1 sediments that affect U(VI) fate and mobility. Even though U(VI) adsorption on the gravel-sized fraction of the sediments is considered to be negligible, careful characterization should be conducted to determine U(VI) adsorption on gravel, because of presence of Fe oxides coatings and diffusion-controlled adsorption into the gravel particles' interior surfaces. A linear adsorption isotherm was observed up to 10(-6) M (238 microg/L) of total U(VI) concentration in batch U(VI) adsorption tests with varying total U(VI) concentrations in spiked groundwater. U(VI) adsorption decreased with increasing concentrations of dissolved carbonate, because strong anionic aqueous uranium-carbonate complexes formed at high pH and high alkalinity conditions. Noticeable uranium desorption hysteresis was observed in a flow-through column experiment, suggesting that desorption K(d) values for aged uranium-contaminated sediments at the Hanford Site can be larger than adsorption K(d) values determined in short-term laboratory experiments and slow uranium release from contaminated sediments into the groundwater is expected.     

天然矿物固硫剂及其对煤粉燃烧的影响

选取CaCO₃、Ca(OH)₂质量配比＝3∶2作为主固硫剂，用钙基固硫剂质量的2％的Na₂CO₃对其改性，利用蛭石作为固硫添加剂。在Ca/S＝2.25的情况下,通过固硫实验考察了主固硫剂以及添加剂的加入对固硫率的影响。实验结果表明，煤粉掺入该固硫剂在950℃下燃烧0.5 h，固硫率可以达到85％。还对添加不同固硫剂的煤粉进行热重实验，分析其对煤粉燃烧特性及动力学参数的影响。结果表明，固硫添加剂的加入不但能提高固硫率，还有利于煤的燃烧，减少灰渣的处理量。     

改性聚合硫酸铁的絮凝特性及其应用

本文较详细地介绍了改性聚合硫酸铁的絮凝机理、净水性能、质量指标、应用范畴及其注意事项,并使用珠江水对几种主要的无机高分子絮凝剂进行了性能测试,结果表明,改性聚合硫酸铁的生产成本最低,净水效果却最显著.     

曝气生物滤池中碳和氮代谢特性

用充填陶瓷滤料的曝气生物滤池研究碳和氮代谢特性.曝气生物滤池进水氨氮为52 mg/L左右、COD为100 mg/L左右和回流比为200%时,经过20多d的运行,出水氨氮小于0.05 mg/L、COD小于25 mg/L、亚硝态氮为4.7 mg/L和硝态氮为7.1 mg/L,COD去除率达75%,氨氮去除率达99.9%,总氮去除率达78%;过大和过小的回流比对曝气生物滤池的运行性能都是不利的.研究成果可以应用于一般城市污水以及含低COD、高氨氮工业废水的处理.