Assessment of estrogen disrupting potency in animal foodstuffs of China by combined biological and chemical analyses

Food has been documented as one of major routes for human exposure to environmental estrogens（EEs）, but information on the occurrence of EEs in animal foodstuffs is still scarce.This study analyzed estrogenic activity in 16 types of animal foodstuffs（n = 142） collected from four cities（Wuhan, Guangzhou, Wenzhou and Yantai） of China by combined yeast estrogen screen（YES） bioassay and chemical analysis. By bioassay, all samples＇ extracts were found to induce estrogenic activities and the bioassay-derived 17β-estradiol equivalent（EEQbio） ranged from 8.29 to 118.32 ng/g. In addition, the samples were analyzed by liquid chromatography coupled to tandem mass spectrometry for further chemical analysis. 17β-Estradiol was found in all samples in this survey at levels of 0.44 to 15.04 ng/g.All samples had 33.1% detection rate of 17α-ethinylestradiol（EE2）, and the maximum concentration was 2.80 ng/g. Bisphenol A and 4-nonylphenols were detected in 83.8% and83.1% of samples, with concentrations up to 12.56 ng/g and 35.76 ng/g, respectively.However, the concentrations of estrone, diethylstilbestrol and 4-t-octylphenol were found to be below the limit of detection. A comparison of EEQbiomeasured from the YES assay and EEQchemcalculated from chemical analysis showed good correlation（R2= 0.84）. Based on the results, the YES assay can be used as a rapid pre-screening method for monitoring the levels of estrogenic activity in large numbers of animal foodstuffs, and chemical analysis used in combination can be used for the identification of specific EEs.     

A nonlinear model for assessing multiple probabilistic risks: a case study in South five-island of Changdao National Nature Reserve in China

Several methods for estimating the potential impacts caused by multiple probabilistic risks have been suggested. These existing methods mostly rely on the weight sum algorithm to address the need for integrated risk assessment. This paper develops a nonlinear model to perform such an assessment. The joint probability algorithm has been applied to the model development. An application of the developed model in South five-island of Changdao National Nature Reserve, China, combining remote sensing data and a GIS technique, provides a reasonable risk assessment. Based on the case study, we discuss the feasibility of the model. We propose that the model has the potential for use in identifying the regional primary stressor, investigating the most vulnerable habitat, and assessing the integrated impact of multiple stressors.     

Short-term metal accumulation and MTLP induction in the digestive glands of Perna virdis exposed to Zn and Cd

Time-dependent Zn and Cd accumulation and metallothionein like protein (MTLP) induction in the digestive glands of mussels, Perna virdis, were measured under different exposure conditions. The initial uptake rate at start of chase (ρ0) and mean residence time (τ) were calculated to determine the physiological response of organisms and their potential detoxification mechanisms. It was found that in digestive glands, Zn had obviously higher ρ0 and shorter mean residence time than Cd, indicating that these two metals had different accumulation dynamics even though they were very close in the periodic element table. MTLP levels in digestive glands varied from 0.51 to 1.05 μg/g ww (wet weight). The MTLP level increased continuously when mussels were exposed to low and middle levels of Zn and Cd media, and reached maximal levels at day 4, then decreased when they were exposed to high level Zn and Cd solutions. With regard to the fraction of Zn and Cd accumulated in the digestive glands, the ratios of soluble metal to total metal decreased continuously after exposure in low and middle levels of Zn and Cd media, and decreased continuously in the first 4 days and then to level off when mussels were exposed to media with high concentration of Zn and Cd. Results suggested that both MTLP induction and metal insolubilization were detoxification processes in digestive glands of mussels.     

模拟实验测定江河中有机物的挥发速率

本文模拟生态体系,测定37种有机物的挥发速率常数,得出有机物的挥发符合一级动力学过程;并用改进的双膜理论模型预测挥发速率常数,结果表明预测值和实测值符合较好;同时介绍了几种参数的测定和佔算方法。     

电驱动道路车辆 动力锂离子电池的试验和要求

本文介绍了电驱动道路车辆动力锂离子电池的试验和要求.是环境试验、电性能试验、安全性试验等专题介绍的第一篇.供实验室和相关产品的供需方参考.     

好氧颗粒污泥降解邻苯二甲酸二甲酯的影响因素研究

本文研究了好氧颗粒污泥系统中,温度、pH、曝气强度、邻苯二酸(Phthalic Acid,PA)及氨氮(NH3-N)对邻苯二甲酸二甲酯(Dimethyl Phthahte,DMP)降解效果的影响,结果表明:好氧颗粒污泥降解DMP的最佳温度、最佳PH值范围、最佳曝气强度分别为25℃～45℃、7.0 ～9.0、1.38 cm/s.当PA浓度为100 mg/L、300 mg/L,PA对DMP降解起促进作用;当PA浓度为500 mg/L、800 mg/L,PA对DMP降解起抑制作用.进水中50 mg/L的氨氮浓度对DMP降解的影响不大.本研究中采用的19种运行工况条件中,除曝气强度为0.33 cm/s以外,其他18种运行工况条件下,当运行时间达到300 min时,DMP的浓度都小于1.0 mg/L,因此,当水力停留时间达到5h以上时,温度、pH、PA、氨氮对DMP降解速率的影响基本上可以忽略不计.     

电驱动道路车辆 动力锂离子电池的非正常工作试验和要求

本文是电驱动道路车辆动力锂离子电池的试验和要求标题下的非正常工作试验部分。结合国标转化过程和实验室能力验证经历,将非正常工作试验方法和要求作描述和解释。供实验室和相关产品的供需方双参考。     

深圳市工业废水的等标污染负荷分析

结合第一次全国污染源普查的统计数据,本文利用等标污染负荷法对深圳市35个二级行业排放的12种污染物进行评价,结果表明,深圳市54．90％的工业污染源分布在通信设备、计算机及其他电子设备制造业,金属制品业,塑料制品业,专用设备制造业,电气机械及器材制造业这5个行业中;深圳市二级行业的等标污染负荷最大的5个行业为：金属制品业〉通信设备、计算机及其他电子设备制造业〉电气机械及器材制造业〉塑料制品业〉仪器仪表及文化、办公用机械制造业,这5个行业中最严重的污染物均为氰化物;工业污染源排放的12种污染物中,最严重的5种污染物为：氰化物〉六价铬〉总铬〉汞〉铅,其中氰化物、六价铬、总铬这3种污染物中最严重的污染行业均为金属制品业,汞、铅这两种污染物中最严重的污染行业均为通信设备、计算机及其他电子设备制造业。     

花生壳中黄酮物质的提取及对油脂的抗氧化作用

对花生壳中黄酮物质的提取工艺进行了优化研究,并对提取物的抗氧化性进行了初步研究。用单因素试验分别对提取溶剂乙醇体积分数、料液比、提取时间及提取温度进行了研究。在此基础上,通过正交试验确定上述4个因素的最佳组合。优化后花生壳中黄酮的最大提取率为92．32％,花生壳中黄酮类化合物的适宜提取条件为乙醇体积分数60％、料液比1：30、提取时间150min、提取温度60℃。花生壳中黄酮类化合物对猪油有明显的抗氧化作用,当添加量为0．2％时抗氧化效果与0．2％BHT接近。     

Mapping wildland-urban interfaces at large scales integrating housing density and vegetation aggregation for fire prevention in the South of France

Every year, more than 50,000 wildland fires affect about 500,000 ha of vegetation in southern European countries, particularly in wildland-urban interfaces (WUI). This paper presents a method to characterize and map WUIs at large scales and over large areas for wildland fire prevention in the South of France. Based on the combination of four types of building configuration and three classes of vegetation structure, 12 interface types were classified. Through spatial analysis, fire ignition density and burned area ratio were linked with the different types of WUI. Among WUI types, isolated WUIs with the lowest housing density represent the highest level of fire risk.