沈阳地区霾与雾的观测研究

利用2009年6月1日-2010年5月31日沈阳大气成分站能见度和大气细粒子的小时观测数据,结合沈阳自动气象站相对湿度的小时观测数据以及天气现象资料,根据<霾的观测和预报等级>和雾的定义,从沈阳1年的资料中判识出霾与雾的出现时次,对沈阳霾与雾的时间变化特征进行初步探讨.结果表明:沈阳全年霾和雾的出现时次分别占总观测时次...     

3-Parameters SPW technique: A new method for evaluation of target safety integrity level

Introduced by IEC-61508 standard, safety integrity levels (SIL) have been used for assessing the reliability of safety instrumented functions (SIF) for protection of the system under control in abnormal conditions. Different qualitative, semi-qualitative and quantitative methods have been proposed by the standard for establishing target safety integrity levels amongst which “Risk Graph” has gained wide attention due to its simplicity and easy-to-apply characteristics. However, this method is subject to many deficiencies that have forced industry men and experts to modify it to fit their demands. In this paper, a new modification to risk graph parameters has been proposed that adds more flexibility to them and reduces their subjective uncertainties but keeps the method as simple as before. Three parameters, namely severity (S), hazard avoidance probability (P), and demand rate (W) are used instead of former four parameters. Hence, the method is named SPW. The outcome results of this method can be directly converted to probability of failure on demand (PFD) or risk reduction factor (RRF). The proposed method has been tested on an example case that has been studied before with conventional risk graph and LOPA techniques. The results show that new method agrees well with LOPA and reduces costs imposed by conservative approximations assumed during application of conventional risk graph.     

Mixed methodology to analyze the relationship between maturity of environmental management and the adoption of green supply chain management in Brazil

The aim of this research is to verify the relationship between the maturity levels of environmental management and the adoption of green supply chain management (GSCM) practices by electro-electronic companies in Brazil. In this work a two-phase research was conducted, with one quantitative and the other qualitative. The quantitative phase aimed to test whether a relationship between the maturity levels of environmental management and GSCM exists, while the qualitative phase tried to detail the characteristics of this relationship. The quantitative phase was conducted through a survey with 100 Brazilian electro-electronic companies and the collected data were processed using Structural Equation Modeling. For the qualitative phase, a multiple case study was conducted with three companies located in Brazil. The results indicate that: (1) The main hypothesis was confirmed and considered statistically valid, indicating that, indeed, the maturity level of environmental management influences the adoption of GSCM practices; (2) a coevolution tends to occur between the environmental maturity and the GSCM practices; that is, the more developed is the company's environmental management, more complex GSCM practices are adopted; and (3) the GSCM internal practices tend to present a greater relative adoption than the external practices; these external practices of GSCM tend to be adopted when the company is inserted in a higher environmental stage and/or operates under a scenario of stronger normative environmental pressure. By the way, this is the first research mixing survey and case studies on GSCM in Brazil.     

“土壤环境质量标准”编制进展

报导了国内外在编制“土壤环境质量标准”的最新进展，论述了编制时应考虑到的一些关键因素，主要包括，编制时依据的技术路线，污染物的种类和形态，土壤性质（ＰＨ、有机质、Ｅｈ、Ｒ２Ｏ３的类型和含量、阳离子代换量和质地）和作物因素，简介了我国最近新编制完成的“土壤环境质量标准”的主要内容，并建议今后补充和进一步完善的部分。     

四川盆地典型城市PM2.5污染过程组分特征和来源解析

为探究四川盆地典型城市PM_2.5污染特征和来源,利用成都市、绵阳市、自贡市超站数据分析2020年冬季典型污染过程PM_2.5组分特征,并采用CMB模型模拟获得研究期间PM_2.5来源及演变特征.结果表明,不同城市PM_2.5组分变化特征不尽相同,成都市污染过程整体呈现NO₃^-主导特征,但重度污染由OC主导.绵阳市污染期间呈现OC主导特征,是污染加重时增长最快的组分.EC是自贡市轻度污染增长最快的组分,NO₃^-、SO₄^2-、NH₄⁺是中度污染增长较快的组分,OC、EC是重度污染增长较快的组分.3个城市均是二次硝酸盐对PM_2.5贡献率最高.比较而言,成都市机动车、扬尘源贡献率均最高;绵阳市二次有机碳贡献率最高,是成都市的2倍;自贡市燃煤源和二次硫酸盐贡献率分别比成都市和绵阳市高出4%~6%和7%~9%.成都市由优良天气到中度污染,二次硝酸盐贡献率随着污染程度的加重而增加,轻度污染较优良天气上升6%,中度污染较轻度污染天气上升3%.中度到重度污染,二次有机碳、机动车贡献率分别上升2%和1%.绵阳市由轻度到重度污染,二次有机碳对PM_2.5的贡献率上升3%,机动车贡献率上升2%,是其污染加重的主要原因.自贡市由轻度到重度污染,各污染源贡献率变化幅度较小.     

起爆药污染场地土壤中锑的环境风险评估

为研究起爆药污染场地土壤中Sb（锑）的环境风险,利用微波消解原子荧光光度法、Tessier逐级提取法、TCLP（toxicity characteristic leaching procedure）毒性浸出法及SBET（simplied bioaccessibility extraction test）方法,分析了某起爆药场地表层土壤中Sb的价态、形态、浸出水平和生物可给性及其对人体健康风险水平和地下水环境风险水平的影响.结果表明:①土壤中w（TSb）为26.7~4 255.0 mg/kg,是GB 36600-2018《土壤环境质量建设用地土壤污染风险管控标准》中第一类用地筛选值的1.33~212.75倍,最大值超过相应管制值的10.82倍.土壤样品中Sb主要以Sb5+存在,w（Sb5+）在w（TSb）中的占比达65.57%~95.46%.②土壤中不同形态Sb的比例由高到低依次为残渣态（38.05%~94.22%）、铁锰氧化物结合态（0.01%~31.80%）、有机结合态（0.32%~21.55%）、碳酸盐结合态（0.01%~11.16%）和可交换态（0.42%~3.70%）.土壤中w（可交换态Sb）与CEC（阳离子交换量）呈负相关,w（铁锰氧化物结合态Sb）与w（Fe）、w（Mn）均呈正相关.③土壤中Sb的浸出浓度为0.22~35.49 μg/L,并随土壤中w（砂粒）、w（TSb）、w（碳酸盐结合态Sb）和w（可交换态Sb）的增大而升高,随CEC的增大而降低.④土壤中Sb的生物可给性范围在8.03%~67.69%之间,w（Fe）和w（OM）的增加能够降低Sb的生物可给性.⑤基于Sb生物可给性健康风险水平和基于Sb价态健康风险水平的结果分别是以w（TSb）为暴露浓度计算的传统风险评估模型预测结果的8.00%~67.69%和62.00%~77.01%,土壤中Sb的实际浸出浓度较常规模型（三相平衡耦合地下水稀释模型）预测值低3~5个数量级.研究显示,充分考虑Sb在起爆药污染场地土壤中的赋存特征能够降低常规风险评估方法的保守性.      

不同磷浓度下菖蒲的生长状况及净化作用研究

研究了菖蒲在不同磷浓度下的生长情况和净化作用。结果表明,菖蒲在0.095-9.751mg/L的TP浓度范围内均生长良好,在TP浓度为0.926mg/L时生长最好、为96.153mg/L时生长受抑制。在试验的32d内,TP浓度为0.926mg/L对磷的去除率高达97.73%。在最初8d内,菖蒲具有较强的吸收净化特性,水体中TP浓度呈下降趋势,磷去除率与水体TP浓度在0.029-0.926mg/L的浓度范围内呈正相关,在0.926-96.153mg/L的浓度范围内呈负相关。菖蒲叶片含磷量与水体初始TP浓度正相关。     

衡水湖湿地生态系统健康评价

在充分考虑衡水湖湿地实际情况的基础上,从湿地生态特征、功能整合性和社会经济环境三个方面的评价指标中筛选出24项指标,同时参考湿地生态系统健康评价体系,得出了适合衡水湖湿地的评价体系。通过专家咨询法计算出各指标的权重,运用多级模糊综合评价模型进行计算,并与指标评价标准进行对比,得出衡水湖湿地生态系统的健康状况和制约湿地健康的因素,在此基础上提出了衡水湖湿地的生态恢复和保护措施。     

ICNIRP限制电磁场暴露的导则(100kHz~300GHz)解读

ICNIRP于2020年3月出版了2020年版《限制电磁场暴露的导则(100 kHz~300 GHz)》,为了准确掌握2020版导则在基本限值和导出限值方面与旧版导则的差异,通过对比新旧导则对应条款得到具体变化情况。2020版导则修订了全身暴露基本限值与导出限值、局部暴露基本限值、神经刺激基本限值、肢体感应电流导出限值,增加了局部暴露导出限值、短暂局部暴露基本限值与导出限值,删除了微波听觉效应基本限值、接触电流导出限值。2020版导则更新了限制射频电磁场暴露的科学基础,使限值更加匹配近年来的科学研究成果,提升了导则的科学性、严谨性和准确性。