江汉平原土地利用对钉螺分布的影响研究

分析了江汉平原2009年易于钉螺孳生的3种土地利用类型（滩地、河渠和水田）比例与钉螺密度的关系。首先,在ERDAS9.2和ENVI4.7软件中对江汉平原2009年的Landsat5TM遥感影像进行了预处理。在已有的多期土地利用数据的基础上,借助eCognition软件利用向量相似度指标来提取土地利用变化区域,结合目视解译经验并运用遥感指标通过建立规则集对变化区域进行分类,将变化区域的分类结果更新2000年数据,得到了该区域2009年的土地利用数据。接下来,整理了江汉平原2009年螺情资料并计算出村级钉螺平均密度,绘制了2009年钉螺分布图。将绘制的钉螺分布图与土地利用分类图叠置分析,并结合收集的螺情数据确定了钉螺易于孳生的3种土地利用类型,分别为滩地、河渠和水田。最后,将钉螺密度与这3种土地利用比例进行线性回归分析。研究结果表明,钉螺密度与这三种土地利用类型比例存在线性回归关系,模型精度为R2=0857。该结论对通过遥感影像来估算钉螺密度具有指导意义,另外也可以为湖北省提出合理用地和灭螺并重的土地利用模式提供一定的科学参考     

活性炭纤维负载TiO2催化剂的制备及其电催化性能

采用溶胶-凝胶法制备了活性炭纤维负载TiO₂催化剂（TiO₂/ACF）,并通过SEM和XRD等手段对TiO₂/ACF进行了表征。以邻苯二甲酸二甲酯（DMP）为目标降解物,考察了催化材料的电催化活性。实验结果表明：在反应温度为25 ℃、初始DMP质量浓度为100.0 mg/L、电解质Na₂SO₄质量浓度为100 mg/L、电流密度为62.5 mA/cm²、电极板间距为4 cm的条件下,经过40 min的降解,DMP质量浓度为1.8 mg/L,DMP去除率为98.2%;TiO₂/ACF在反应过程中可以原位再生,经6次重复使用后仍保持很高的催化活性,对DMP的去除率仍达90%以上。     

Environmental lead pollution threatens the children living in the Pearl River Delta region, China

Introduction and purpose

The objective of this study is to determine children??s blood lead levels and identify sources of lead exposure. Childhood lead exposure constitutes a major pediatric health problem today in China. A blood lead screening survey program for children in the age group of 2?C12?years residing in Pearl River Delta region, south of China, was carried out from Dec 2007 to Jan 2008.

Methods

Blood lead levels and lead isotope ratios of a total of 761 participants were assessed by inductively coupled plasma mass spectroscopy. Measurements of urban environmental samples for source identification of children lead exposure were also performed.

Results and conclusions

The geometric mean value of the children??s blood lead levels was 57.05???g/L, and 9.6% of them were higher than 100???g/L. The blood lead levels were still much higher than those in developed countries. Based on the data of environmental lead source inventories, lead isotopic tracing revealed that there is about 6.7% past used gasoline Pb embedded in Shenzhen residential dust and about 15.6% in Guangzhou dust, respectively.     

Effects of nano-copper(II) oxide and nanomagnesium oxide particles on activated sludge

Effects of nano-copper(II) oxide (nano-CuO) and nanomagnesium oxide (nano-MgO) particles on activated sludge endogenous respiration (aerobic digestion), biochemical oxygen demand (BOD) biodegradation, and nitrification were investigated through respiration rate measurement. For comparison, the effects of Cu(II) and Mg(II) ions on activated sludge were also studied. Results indicated that soluble Cu(II) has half maximum inhibitory concentration (IC50) values of 19, 5.5, 53, and 117 mg Cu/L for endogenous respiration, BOD biodegradation, ammonium oxidation, and nitrite oxidation, respectively. However, nano-CuO only inhibited BOD biodegradation at 240 mg Cu/L or more, and its associated toxicity was primarily caused by soluble Cu(II). In contrast, soluble Mg(II) was not toxic to activated sludge in the experimental concentration range, but nano-MgO inhibited BOD biodegradation and nitrification with IC50 values of 70 and 143 mg Mg/L, respectively. Further study indicated that the toxicity of nano-MgO resulted primarily from increased pH following MgO hydrolysis.     

油田作业废水高效处理技术中试研究

文章根据新疆油田作业废水特征及油田地处干旱区的地理特点,结合国内外含聚合物污水处理的技术现状,以及油田连续生产稳定运行的要求,在含油污水处理技术的基础上,开展了作业废水处理关键技术研究和工艺优化,采用了"隔油—絮凝气浮—深层过滤"技术。中试试验结果表明:处理后废水COD_(Cr)、石油类、SS可分别由680 mg/L、98.6 mg/L、56.2 mg/L降至98.8 mg/L、5.4 mg/L、4.5 mg/L,去除率分别为85.5%、94.5%、92.0%。     

高校节能管理初探

目前,低碳生活的方式和理念已渗透到各高校大学生的学习和生活中,这为高校的节能管理创造了良好的基础和条件。倡导节约资源之风,尽节约能源之责,是建设生态文明社会的一项紧迫任务。因而,提高节能意识、完善节能管理体制、科学使用节能设备、加强节能队伍建设等措施必将促进高校节能管理工作的顺利开展。     

基于响应曲面法优化烧结烟气脱硫灰改性工艺

采用BOX-Behnken的中心组合实验设计及响应面分析方法对半干法烧结烟气脱硫灰进行改性研究,得到脱硫灰转化率的预测模型。结果表明:通过该预测模型可以很好地描述脱硫灰的转化率与反应温度、反应时间和气固比等重要操作参数之间的关系,R2=0.9903。因素分析表明,反应温度对脱硫灰的转化率影响最大,同时反应温度和气固比的交互作用与反应温度和时间的交互作用对脱硫灰的转化率的影响作用相同。利用得到的改进预测模型可以计算脱硫灰的转化率。     

铁炭微电解法降解TAIC废水

TAIC（三烯丙基异氰脲酸酯）作为过氧化物交联或自由基反应交联的助交联剂被广泛应用。由于TAIC性质稳定难于生物降解,采用铁炭微电解法处理TAIC生产废水,并考察了铁炭比、进水pH值、反应时间对处理效果的影响,以及TAIC降解机理和反应动力学过程。结果表明,影响微电解工艺的因素主次关系为：pH>Fe/C质量比>反应时间;在最佳条件进水pH值为5,铁炭质量比为2：1,反应时间为135 min时,COD的去除率达到46%以上,TAIC的去除率达到48%以上。TAIC去除机理研究表明,微电解对TAIC废水的作用主要通过·H的还原和铁离子的絮凝作用,其中·H的还原作用是TAIC降解的主要原因。反应动力学分析表明,铁炭微电解法处理TAIC的降解过程基本符合二级反应动力学规律,通过建立模型并拟合出了TAIC降解的二级反应动力学方程。     

Synergistic toxic effect of nano-Al2O3 and As(V) on Ceriodaphnia dubia

Engineered nanomaterials (ENMs) alone could negatively impact the environment and human health. However, their role in the presence of other toxic substances is not well understood. The toxicity of nano-Al(2)O(3), inorganic As(V), and a combination of both was examined with C. dubia as the model organisms. Bare nano-Al(2)O(3) particles exhibited partial mortality at concentrations of greater than 200mg/L. When As(V) was also present, a significant amount of As(V) was accumulated on the nano-Al(2)O(3) surface, and the calculated LC(50) of As(V) in the presence of nano-Al(2)O(3) was lower than that it was without the nano-Al(2)O(3). The adsorption of As(V) on the nano-Al(2)O(3) surface and the uptake of nano-Al(2)O(3) by C. dubia were both verified. Therefore, the uptake of As(V)-loaded nano-Al(2)O(3) was a major reason for the enhanced toxic effect.