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51.
以辽宁省最大的硫酸生产企业(辽西某锌厂)为研究对象,剖析了硫酸含汞问题的来源,论述了该厂原料、中间产品、最终产品、车间内外环境汞的污染状况。并论述了使用该厂硫酸的十大企业的中间产品、最终产品的含汞状况,给出了厂内外环境受汞污染的测定结果,研究表明含汞硫酸污染问题是急待解决的重要问题。  相似文献   
52.
水环境中药品和个人护理用品污染现状及研究进展   总被引:6,自引:0,他引:6  
综述了当前国内外药品和个人护理用品(PPCPs)在地表水、地下水和饮用水中的污染现状,介绍了水环境中PPCPs污染的危害及其预测、调查与检测方法。提出了我国水环境中PPCPs污染未来的研究方向,包括改进水处理工艺,提高PPCPs的去除效率;提升分析技术水平,拓宽PPCPs的检测种类;深入研究PPCPs产生的环境效应,重视其职业暴露的污染与危害;建立水环境中PPCPs的预测制度及风险评价体系。  相似文献   
53.
Abstract

The persistence of aflatoxin in the soil environment could potentially result in a number of adverse environmental consequences. To determine the persistence of aflatoxin in soil, 14C‐labeled aflatoxin B1, was added to silt loam, sandy loam, and silty clay loam soils and the subsequent release of 14CO2 was determined. After 120 days of incubation, 8.1% of the original aflatoxin added to the silt loam soil was released as CO2 ? Aflatoxin decomposition in the sandy loam soil proceeded more quickly than the other two soils for the first 20 days of incubation. After this time, the decomposition rate declined and by the end of the study, 4.9% of the aflatoxin was released as CO2. Aflatoxin decomposition proceeded most slowly in the silty clay loam soil. Only 1.4% of aflatoxin added to the soil was released as CO2 after 120 days incubation. To determine whether aflatoxin was bound to the silty clay loam soil, aflatoxin B1 was added to this soil and incubated for 20 days. The soil was periodically extracted and the aflatoxin species present were determined using thin layer chromatographic (TLC) procedures. After one day of incubation, the degradation products, aflatoxins B2 and G2, were observed. It was also found that much of the aflatoxin extracted from the soil was not mobile with the TLC solvent system used. This indicated that a conjugate may have formed and thus may be responsible for the lack of aflatoxin decomposition.  相似文献   
54.
文中论述了新疆地区乡镇企业发展与生态环境有关的产业结构特点和分布,分地区、分行业计算了乡镇工业1985—1988年的“三废”污染和生态破坏状况,并对1995年和2000年“三废”污染控制数量及生态—经济规划指标作了综合评述。提出了新疆乡镇企业经济与生态环境保护协调发展战略的主要对策和建议。  相似文献   
55.
Energy and carbon balances of wood cascade chains   总被引:1,自引:0,他引:1  
In this study we analyze the energy and carbon balances of various cascade chains for recovered wood lumber. Post-recovery options include reuse as lumber, reprocessing as particleboard, pulping to form paper products, and burning for energy recovery. We compare energy and carbon balances of chains of cascaded products to the balances of products obtained from virgin wood fiber or from non-wood material. We describe and quantify several mechanisms through which cascading can affect the energy and carbon balances: direct cascade effects due to different properties and logistics of virgin and recovered materials, substitution effects due to the reduced demand for non-wood materials when wood is cascaded, and land use effects due to alternative possible land uses when less timber harvest is needed because of wood cascading. In some analyses we assume the forest is a limiting resource, and in others we include a fixed amount of forest land from which biomass can be harvested for use as material or biofuel. Energy and carbon balances take into account manufacturing processes, recovery and transportation energy, material recovery losses, and forest processes. We find that land use effects have the greatest impact on energy and carbon balances, followed by substitution effects, while direct cascade effects are relatively minor.  相似文献   
56.
开发研制绿色化学产品   总被引:1,自引:0,他引:1  
叙述绿色化学是一门从源头上彻底阻止污染的化学,简介了几种绿色化学产品及研究开发的进展。  相似文献   
57.
文章回顾了我国环保产品认证发展的历史沿革,阐述了环保产品认证的范围、模式、特点以及环保产品认证取得的成效、作用和实现的目标。  相似文献   
58.
建筑材料和制品燃烧性试验规范对保证建筑物内人的生命安全和财产安全是极为重要的。笔者对美国、加拿大、欧盟、日本以及中国的建筑材料燃烧性能试验规范进行分析、比较和综述。通过研究认为美国和加拿大对建筑材料燃烧性能的要求和试验方法基本相似,他们主要针对材料的燃烧性、火焰传播进行检测;欧盟于2001年颁布了新的燃烧性分级体系,该分级体系包括专门针对铺地材料部分和针对其他所有建筑构件材料和产品部门;日本采用锥形量热计法(ISO5660)将内装饰材料分为不燃、准不燃和阻燃材料3个等级;我国对建筑材料的试验方法包括不燃性试验方法、墙和天花板内装饰材料的三级分级体系和铺地材料两级分级体系。  相似文献   
59.
In the present research, the effects of static magnetic field, with or without iron on the growth, the activity of certain enzymes (like polyphenol oxidase and phenyle alanine ammonialyase), the content of phenolic compounds and the essential oil composition of sweet basil (Ocimum basilicum) were studied. Treatment of plants with static magnetic field with or without iron led to decrease of the growth of plants as well as decrease in the activity of phenyle alanine ammonialyase and of phenolic compounds content. In addition in those plants exposed to magnetic field the amount of essential oils, notably of methyl chavicol, was increased. Exposure of plants to the magnetic field decreased the activity of polyphenol oxidase, whereas treatment of plants with iron when exposed to magnetic field increased polyphenol oxidase activity. In this group the content of essential oil was reduced.  相似文献   
60.
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