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711.
It was recently reported that radioactive fallout due to the Fukushima Nuclear Accident was detected in environmental samples collected in the USA and Greece, which are very far away from Japan. In April-May 2011, fallout radionuclides (134Cs, 137Cs, 131I) released in the Fukushima Nuclear Accident were detected in environmental samples at the city of Krasnoyarsk (Russia), situated in the center of Asia. Similar maximum levels of 131I and 137Cs/134Cs and 131I/137Cs ratios in water samples collected in Russia and Greece suggest the high-velocity movement of the radioactive contamination from the Fukushima Nuclear Accident and the global effects of this accident, similar to those caused by the Chernobyl accident.  相似文献   
712.
萘普生为水体中常见的一种非甾体药物类污染物。以300W汞灯为光源,研究紫外光照降解法对于含低浓度萘普生废水的处理效果,发现pH对萘普生光解效果有直接影响,降解优异性顺序为酸性>碱性>中性。通过实验,确定了萘普生光解的最佳pH值为4,光照时间为40 min,在该实验条件下,萘普生的降解率达到97.6%。通过液相色谱-质谱联用法对降解后水样进行检测,初步推导出光解中间产物为6-甲氧基-2-乙酰基萘、6-甲氧基-2-乙烯萘及β-萘酚。  相似文献   
713.
洪俊辉 《环境工程学报》2013,7(6):2361-2366
利用焙烧的方法处理沉钒废水蒸发浓缩后的硫酸盐渣,干燥条件为130~160℃下1~1.5 h,焙烧条件为550~600℃下0.5~1 h,能够将废渣中的硫酸铵彻底分解,得到满足GB/T 6009-2003《工业无水硫酸钠》要求的硫酸钠产品。  相似文献   
714.
简介了目前我国环保产品标准的施行现状,以及环保产品认证的模式、依据、作用等,结合环保产品认证的三个环节中涉及环保产品标准实施的内容,阐述了全面开展环保产品认证对宣传贯彻环保产品标准的实施起到的积极推动作用。  相似文献   
715.
徐州市电磁辐射环境的污染现状调查及评价   总被引:3,自引:0,他引:3  
调查了徐州市电磁辐射污染源的状况,分析了其电磁辐射环境质量的现状,并对全市电磁辐射环境质量进行了评价,指出了分析工作中存在的问题,提出了防治对策。  相似文献   
716.
Exposure to endocrine disrupting chemicals such as bisphenol A (BPA) and phthalates is prevalent among children and adolescents, but little is known regarding important sources of exposure at these sensitive life stages. In this study, we measured urinary concentrations of BPA and nine phthalate metabolites in 108 Mexican children aged 8–13 years. Associations of age, time of day, and questionnaire items on external environment, water use, and food container use with specific gravity-corrected urinary concentrations were assessed, as were questionnaire items concerning the use of 17 personal care products in the past 48-h. As a secondary aim, third trimester urinary concentrations were measured in 99 mothers of these children, and the relationship between specific gravity-corrected urinary concentrations at these two time points was explored. After adjusting for potential confounding by other personal care product use in the past 48-h, there were statistically significant (< 0.05) positive associations in boys for cologne/perfume use and monoethyl phthalate (MEP), mono(3-carboxypropyl) phthalate (MCPP), mono(2-ethyl-5-hydroxyhexyl) phthalate (MEHHP), and mono(2-ethyl-5-oxohexyl) phthalate (MEOHP), and in girls for colored cosmetics use and mono-n-butyl phthalate (MBP), mono(2-ethylhexyl) phthalate (MEHP), MEHHP, MEOHP, and mono(2-ethyl-5-carboxypentyl) phthalate (MECPP), conditioner use and MEP, deodorant use and MEP, and other hair products use and MBP. There was a statistically significant positive trend for the number of personal care products used in the past 48-h and log-MEP in girls. However, there were no statistically significant associations between the analytes and the other questionnaire items and there were no strong correlations between the analytes measured during the third trimester and at 8–13 years of age. We demonstrated that personal care product use is associated with exposure to multiple phthalates in children. Due to rapid development, children may be susceptible to impacts from exposure to endocrine disrupting chemicals; thus, reduced or delayed use of certain personal care products among children may be warranted.  相似文献   
717.
凹凸棒粘土是一种自然界较稀少、性能独特、用途广泛的非金属矿产.凹凸棒粘土流变性良好,具有独特的胶体性能,是理想的无机胶凝材料,其表面物理化学结构及离子状态使其具有良好的吸附性能.凹凸棒粘土具有载体功能,可作为催化剂的载体,同时还可作为缓释肥料和农药的载体.凹凸棒粘土表面有结构残基、表面羟基使其具有补强性能,在石油、化工、食品、环保、农药、医药、建材等领域得到了广泛的应用.利用我国凹凸棒土资源丰富的特点,加快技术创新,使我国凹凸棒粘土工业跻身于世界先进之列.  相似文献   
718.
通过与国内针刺生产设备的对比,对进口Dilo针刺技术的优势、设备构造、自动化性能,以及产品的指标参数等进行了阐述,认为采用先进生产设备不仅能够提高企业产品的产量和质量,而且对企业自身的发展有促进作用。  相似文献   
719.
提出面板数据空间误差分量模型,采用基于广义矩1估计的可行广义最小二乘法估计方法,研究1997-2007年间,我国省级CO2排放的影响因素.实证结果表明,我国省级CO2排放量存在显著的正向空间相关性,CO2排放较多的省份往往会影响邻近地区的CO2排放;CO2排放量与人均GDP呈倒N型环境库兹涅兹曲线.未考虑空间相关性时,CO2排放转折点为人均GDP 51 73O元,我国目前仍处于CO2排放量上升期;采用面板数据空间误差分量模型修正后,CO2排放下降转折点为人均GDP约53 237元,较未考虑空间因素时有所提高,省际间的空间相互影响,对CO2排放下降转折点的人均GDP提出更高的要求;实证研究结果同时显示,煤炭消费比重提高及人口数量增大,都将显著增加我国CO2排放量,体现优化能源结构和控制人口增长对抑制CO2排放增长的重要性.  相似文献   
720.
Stefaniak AB  Virji MA  Day GA 《Chemosphere》2011,83(8):1181-1187
Dissolution of a lung burden of poorly soluble beryllium particles is hypothesized to be necessary for development of chronic beryllium lung disease (CBD) in humans. As such, particle dissolution rate must be sufficient to activate the lung immune response and dissolution lifetime sufficient to maintain chronic inflammation for months to years to support development of disease. The purpose of this research was to investigate the hypothesis that poorly soluble beryllium compounds release ions via dissolution in lung fluid. Dissolution kinetics of 17 poorly soluble particulate beryllium materials that span extraction through ceramics machining (ores, hydroxide, metal, copper-beryllium [CuBe] fume, oxides) and three CuBe alloy reference materials (chips, solid block) were measured over 31 d using artificial lung alveolar macrophage phagolysosomal fluid (pH 4.5). Differences in beryllium-containing particle physicochemical properties translated into differences in dissolution rates and lifetimes in artificial phagolysosomal fluid. Among all materials, dissolution rate constant values ranged from 10−5 to 10−10 g cm−2 d−1 and half-times ranged from tens to thousands of days. The presence of magnesium trisilicate in some beryllium oxide materials may have slowed dissolution rates. Materials associated with elevated prevalence of CBD had faster beryllium dissolution rates [10−7-10−8 g cm−2 d−1] than materials not associated with elevated prevalence (p < 0.05).  相似文献   
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