Effect of composting process on phytotoxicity and speciation of copper, zinc and lead in sewage sludge and swine manure

The concentration and bioavailability of heavy metals in composted organic wastes have negative environmental impacts following land application. Aerobic composting procedures were conducted to investigate the influences of selected parameters on heavy metal speciation and phytotoxicity. Results showed that both of sewage sludge (SSC) and swine manure (SMC) composting systems decreased the pH, the content of organic matter (OM) and dissolved organic carbon (DOC), and total amounts of Cu, Zn and Pb. Sequential extraction showed that readily extractible fractions of exchangeable and carbonate in Cu and Zn increased during SSC composting but decreased during SMC composting, thus their bioavailability factors (BF) enhanced in SSC but declined in SMC. The fraction of reducible iron and manganese (FeMnOX) of Cu and Zn in SSC and FeMnOX-Cu in SMC decreased, but FeMnOX-Zn in SMC gradually increased in the process of compost. In contrast, the changes of Pb distributions were similar in two organic wastes. Pb was preferentially bound to the residual fraction and its BF decreased. The evolution of heavy metal distributions and BF depended on not only total metal concentrations but also the other properties, such as pH, decomposition of OM and decline of DOC. The germination rate (RSG), root growth (RRG) and germination index (GI) of pakchoi (Brassica Chinensis L.) increased during the composting process. Linear regression analysis demonstrated that GI, which could represent phytotoxic behavior to the plants, could be poorly predicted by BF or total amount of metals, i.e., BF-Zn, T-Cu. However, the inclusion of other physicochemical parameters (pH, OM and DOC) could enhance the linear regression significances (R).     

灰色综合评判法与大气环境质量评价

依据灰色理论中白化函数的构造原则和聚类原理，提出了灰色综合评判法，并以大气环境质量评价为例作了说明。该法以等斜率方式构造白化函数，拓展了白化函数中污染物浓度的取值范围，有较高的信息利用率。评价结果能同时给出各评价对象所属的污染级别和各评价对象之间环境质量的优劣，具有较强的实用性。     

Removal of Cd2+ from water by Friedel's salt (FS:3CaO·Al2O3·CaCl2·10H2O): Sorption characteristics and mechanisms

The development of low-cost and efficient new mineral adsorbents has been a hot topic in recent years.In this study,Friedel's salt (FS:3CaO·Al2O3·CaCl2·10H2O),a hexagonal layered inorganic absorbent,wa...     

印染废水中低含量阴离子洗涤剂的二次标准加入法测定

用次氯酸钠-亚硝酸钠-氨基磺酸铵颅处理,以消除染料对测定的干扰;采用二次标准加入法,并利用简单的迭代运算,求得被测液中阴离子洗涤剂含量。本方法对印染废水的测定上下限分别为6.0mg/L和0.75mg/L。经5个实验室对LAS含量为0.78mg/L和6.7mg/L的实际印染废水的协作试验验证,其重复性相对标准偏差分别为5.0和4.5％,再现性相对标准偏差为5.2和9.7％。     

上海工业街坊噪声对职工健康影响的研究和对策

作者对上海工业街坊固定源和流动源噪声进行了调查和测试,取得了大量的数据,找出了工业街坊中主要噪声源和噪声级的变化范围,提出了大城市工业区域噪声评价的方法并进行评价,得出各工业街坊噪声污染指数与评价等级。文章将处于此噪声等级下的职业工人和居民的职业病与人体健康状况,进行了特异性损伤与非特异性损伤的分析,并重点研究了纺织业等工业噪声对职工健康的影响。文章最后就工业街坊噪声污染治理对策,提出了合理工业布局和建立低噪声工业街坊的必要性。     

线源扩散的快速模拟

提出了一种计算风向与线源成任意角时任意长地面线源大气扩散的简化模式。通过与数值积分方法计算结果的比较表明,模式的最大相对误差在风向与线源平行时最大,但不超过18％。随风向与线源夹角的增大,相对误差迅速减小,当夹角大于5°时,已小于2％。为城镇公路网大气扩散的快速、准确模拟提供了新手段。     

中国几种土壤中的有机态硒及其分布特征

采用0.1mol/L NaOH-0.1mol/L Na_4P_2O_7浸提,活性碳分离技术研究了中国湿润半湿润地区几种土壤中有机态硒的化学特征.供试土壤有机态硒占全硒含量的百分数变幅为3.46％—59.86％,平均28.42％.影响有机硒含量的主要因素有全硒含量(r=0.8033)、有机碳含量(r=0.6618)、土壤交换性酸(r=0.6136)和pH(r=-0.5248)。土壤有机质的C/Se为0.58×10~6-42.93×10~6,平均为6.38×10~6.低硒环境土壤有机质的C/Se显著高于正常硒含量土壤.以平均计,胡敏酸结合态硒约占有机态硒的34％,富啡酸结合态硒占66％.缺硒土壤有机态硒中,胡敏酸结合态硒的比例一般都较高.     

HgCl2对斑马鱼SOD,AChE酶活性和基因相对转录量的影响

以HgCl2为实验毒物,研究其对斑马鱼的毒性效应,经染毒后,分别在第1天和第7天取斑马鱼的肌肉测定超氧化物歧化酶(SOD)、乙酰胆碱酯酶(AChE)活性,半定量RT-PCR检测肌肉中乙酰胆碱酯酶、细胞色素P450(CYP 1A)和超氧化物歧化酶(Cu/Zn-SOD)基因的相对转录量.结果显示HgCl2对斑马鱼的毒性很强...     

厌氧膜生物反应器处理高浓度食品废水的应用

采用由完全混合的厌氧生物反应器和板杠式超滤膜组成的膜生物反应器对高浓度食品放心水进行处理,考察了厌氧膜生物反应器的处理效果及其对负荷、水力停留时间等的稳定性,膜组件装填面积为０．６４ｍ＾２,膜材质为聚醚砚（ＰＥＳ）,膜截贸分子量为２００００。结果表明：ＣＯＤ负荷在２～３ｋｇ／（ｍ＾３．ｄ）时,膜出水ＣＯＤ去除率可达８０％～９０％,当ＣＯＤ负荷超过４．５ｋｇ（ｍ＾３．ｄ）时,混合液ＶＦＡ出现积累,Ｃ     

青岛市臭氧污染与非污染期间VOCs化学特征及来源解析

青岛市夏季臭氧浓度水平高且污染事件频发,开展臭氧污染过程和非污染时期的挥发性有机物(VOCs)及其臭氧生成潜势(OFP)的精细化来源解析研究,对于有效降低沿海城市的大气臭氧污染,持续改善环境空气质量将会发挥重要的作用.因此,利用青岛市2020年夏季(6～8月)小时分辨率的在线VOCs监测数据,分析臭氧污染过程和非臭氧污染时期环境VOCs的化学特征,并通过正定矩阵因子分解(PMF)模型进行了环境VOCs及其OFP的精细化来源解析研究.结果表明,青岛市夏季环境ρ(TVOCs)平均值为93.8μg·m^-3,臭氧污染过程相较于非臭氧污染时期TVOCs浓度上升了49.3%,其中芳香烃浓度增加最显著,增加了59.7%.夏季环境VOCs总的OFP达到246.3μg·m^-3,臭氧污染过程相较于非臭氧污染时期环境VOCs的总OFP增加了43.1%;其中烷烃增加最多,增加了58.8%.间-乙基甲苯和2,3-二甲基戊烷是臭氧污染过程中OFP增加幅度最大的物种.青岛市夏季环境VOCs的主要贡献源为柴油车(11.2%)、溶剂使用(4.7%)、液化石油气及天然气(27....