Dissipation and residue of 2,4-D isooctyl ester in wheat and soil

A simple analytical method was developed to determine the 2,4-D isooctyl ester residue in wheat and soil by gas chromatography coupled with electron capture detector. Using the method, the dissipation and residue of 2,4-D isooctyl ester in wheat field was investigated. The average recoveries of 2,4-D isooctyl ester ranged from 80.1% to 110.0% with relative standard deviations of 2.4% to 16.1%. The pesticide showed a rapid dissipation rate either in wheat seedling or soil, with the half-lives of 1.0 to 3.0 days. The terminal residue results in wheat grain were much lower than the codex MRL (2.0 mg/kg). It could be considered safe to food and environment when using this herbicide for controlling weeds in wheat field.     

绿色屋顶径流水质监测研究进展

概述了国内外绿色屋顶径流水质监测发展状况,并从绿色屋顶径流收集、降雨场次、监测指标、径流水质和污染物传输的影响因子等方面进行了归纳和总结。基于水量和水质管理,从几何尺寸、土壤类型和厚度、植被和维护等方面阐述了绿色屋顶在城市排水系统中的作用和地位。揭示了绿色屋顶需要开展长期的监测和研究,绿色屋顶径流水质监测逐渐向采样自动化和分析自动化方向发展。     

石河子燃煤电厂重金属排放研究

选取石河子市典型燃煤电厂,对其燃煤烟气重金属排放浓度及飞灰、底渣、脱硫石膏重金属的富集进行定量分析。结果表明,烟气中各重金属排放浓度从高到低依次为Zn、Ni、Cr、Pb、Cu、Hg、Co、Cd、As。各重金属元素在飞灰中的富集程度较高,除Hg、Cd、Ni外,其他重金属元素在飞灰的富集因均值均大于5。其中,As在飞灰的富集因子均值为5.76。研究结果可为石河子重金属污染控制提供基础数据。     

GC和HPLC测定水中苦味酸的比较

建立了气相色谱法(GC)和高效液相色谱法(HPLC)测定水中苦味酸的分析方法,并对2种方法进行比较。GC法检出限为0.000 4 mg/L,线性范围为0.0~0.050 mg/L,加标回收率为92.3%~94.1%,相对标准偏差为4.6%~8.9%。HPLC法检出限为0.02 mg/L,线性范围为0.10~5.00 mg/L,加标回收率为93.7%~96.5%,相对标准偏差为1.3%~2.0%。2种方法相比,GC法灵敏度较高,可用于痕量分析,但操作烦琐,不能有效地将苦味酸与硝基酚类干扰物分离;而HPLC法虽然灵敏度较差些,但简单、快速、稳定性好、准确度高,可有效地将苦味酸与硝基酚类干扰物分离。     

Binding of the veterinary drug tetracycline to bovine hemoglobin and toxicological implications

Tetracycline (TC) is a widely used veterinary drug in animal breeding and fishery. Because of its low bioavailability, the TC residue extensively exists in the environment (e.g. soils, lakes and rivers), which can enter the human body, being potentially harmful. Hemoglobin (Hb) is a protein responsible for oxygen carrying in the vascular system of animals. The aim of this study was to investigate the interaction of bovine hemoglobin (BHb) with TC through spectroscopic and molecular modeling methods. The experimental results revealed that TC can interact with BHb with one binding site to form a TC-BHb complex, mainly through van der Waals interactions and hydrogen bonds. The UV-visible absorption, synchronous fluorescence, and circular dichroism (CD) results revealed that the binding of TC can cause conformational and some microenvironmental changes of BHb, which may affect BHb physiological functions. The synchronous fluorescence experiment disclosed that TC binds into BHb central cavity, which was verified by molecular modeling study. The work contributes to clarify the molecular mechanism of TC toxicity in vivo.     

多孔孔板水力空化反应器的水力特性

设计不同孔分布的孔板空化反应器,通过测定空化数及.OH产生量,研究多孔孔板水力空化反应器空化特性,为高性能多孔孔板水力空化反应器的设计奠定基础。实验结果表明,空化数随孔板孔径的增加、入口压力的减小和溶液温度的升高而增大;.OH产生量随孔板孔径的减小和运行时间的增加而增加,随入口压力和溶液温度的升高先增加后减小。结果表明,多孔孔板水力空化反应器的水力空化效果与孔板结构及操作条件有关。     

自制填料与常用湿地填料除磷能力的比较

用石英砂、石灰、水泥和铝粉等材料制作人工湿地填料,并对自制填料、粉煤灰块和钢渣等6种填料的等温吸附特性进行研究,发现自制填料在较低与较高浓度P溶液中吸附率都最高,在P浓度为(10～50 mg/L)时,平均吸附率达96.8%,其次是粉煤灰和钢渣,分别为87.6%和85.4%;填料对P的理论饱和吸附量分别为:自制填料(2 413.6 mg/kg)>粉煤灰块(1 605.8 mg/kg)>钢渣(1 277.5 mg/kg)>碎砖(451.6 mg/kg)>碎石(182.5 mg/kg)>砾石(18.4 mg/kg);填料中金属矿物成分含量高、比表面积大,是除P效果好的原因。     

集中供热锅炉烟气脱硝技术的开发与应用

通过锅炉结构的改进、SCR工艺装置的优化、快速跟踪负荷变化的还原剂制备及控制调节技术的开发和应用等系统性的工作,有效满足了集中供热锅炉房烟气脱硝工程的技术要求,成功开发了集中供热锅炉烟气脱硝技术。在实际工程应用中,确保了在不同负荷段下,锅炉至SCR装置入口段的温度满足脱硝要求,SCR工艺装置能够在不同负荷下连续稳定运行并很好地跟踪负荷的变化,确保氨逃逸率满足设计要求,保证锅炉的安全稳定运行。     

腐熟污泥对废水中Cd(Ⅱ)与Zn(Ⅱ)的吸附性能研究

利用腐熟污泥作为一种重金属吸附剂,考察其对水中重金属锌和镉的吸附过程.实验数据的拟合采用了Pseudo-first Order-和Pseudo-second Order 2种动力学模型以及Langmuir和Freundlich 2种吸附等温线模型;拟合结果表明,腐熟污泥对锌与镉的吸附过程符合Pseudo-second ...     

UASB反应器中厌氧氨氧化菌的影响因素研究

在UASB反应器中接种实验室已经驯化好的厌氧氨氧化颗粒污泥,对其进行厌氧氨氧化菌活性提高和影响因素的实验研究。研究表明厌氧氨氧化菌对NH4＋-N和N02--N的适宜浓度负荷均为200mg／L,适宜水力停留时间HRT、温度、pH和进水基质比（N02--N／NH4＋-N）分别为2h、30～35℃、7．5～8．5和0．95～1．2,NH4＋-N、NO2--N和TN的平均去除率分别为97．1％、98．3％和92．7％。