Comprehensive estimate of the theoretical maximum daily intake of pesticide residues for chronic dietary risk assessment in Argentina

A chronic dietary risk assessment for pesticide residues was conducted for four age groups of the Argentinian population following the procedure recommended by the WHO. The National Theoretical Maximum Daily Intake (NTMDI) for 308 pesticides was calculated for the first time, using the Maximum Residue Limits (MRLs) from several Argentinean regulations and food consumption data from a comprehensive National Nutrition and Health Survey. The risk was estimated by comparing the TMDI with the Acceptable Daily Intakes (ADI) identified by various sources. Furthermore, for each of the compounds with a TMDI >65% of the ADI, a probabilistic analysis was conducted to quantify the probability of exceeding the ADI. In this study 27, 22, 10, and 6 active ingredients (a.i.) were estimated to exceed the 100% of the ADI for the different population groups: 6–23 month-old children, 2–5 year-old children, pregnant women, and 10–49 year-old women, respectively. Some of these ADI-exceeding compounds (carbofuran, diazinon, dichlorvos, dimethoate, oxydemeton-methyl and methyl bromide) were found in all four of these groups. Milk, apples, potatoes, and tomatoes were the foods that contributed most to the intake of these pesticides. The study is of primary importance for the improvement of risk assessment, regulations, and monitoring activities.     

小型好氧堆肥设备处理有机垃圾

针对我国生活垃圾的特点,提出了厨余等有机生活垃圾单独收集,在产生源头进行好氧堆肥处理。研制了好氧堆肥设备,由加热装置、通风装置、冷凝水收集和回灌装置,以及与该生物堆肥设备配套的生物过滤除臭装置、自控系统和数据采集软件几部分构成。自控系统由氧气、温度、湿度三路传感器以及2个控制器构成,并与加热装置、通风装置连接,能满足物料加热、供氧和散热的要求。本研究通过为期30 d的试运行实验表明,物料快速升温并稳定保持在高温阶段(50～60℃),物料中的氧气浓度保持在14%～16%范围内。在堆肥实验结束时,物料的含水率降至36.4%,有机质含量降至49%,另外,通过好氧速率指标也可判定物料达到腐熟。     

Fenton试剂降解PAM催化剂的研究

采用Fenton试剂氧化降解含油废水中的聚丙烯酰胺,研究了H2O2用量、催化剂种类及用量对降解聚丙烯酰胺效果的影响。结果表明,H2O2用量为聚丙烯酰胺的20%为宜;CuCl2具有和FeSO4、Fe(NO3)3、FeCl3相近的催化效果,并且可以作为一种在较高pH值条件下应用的催化剂;在优选条件下该氧化体系可以使聚丙烯酰胺黏度大大降低。     

CFD分析在烟气脱硫中的实际运用与研究

为降低某公司烧结机干法脱硫装置烟道阻力,减少引风机出力,实现节能优化,运用计算流体力学软件,对引风机出口烟道内流场进行三维数值模拟,并根据分析结果进行烟道的优化改造。改造后,吸收塔入口负压由-200Pa提升至-560Pa,风机电流由328A降为301.4A,节能降耗显著。     

零价铁类Fenton试剂氧化降解废水中有机污染物的研究进展

综述了近年来国内外Fe0类Fenton试剂氧化反应降解废水中有机污染物的研究现状,介绍了Fe0-H2O2体系、紫外光-Fe0-H2O2体系和可见光-Fe0-H2O2体系处理有机污染物的机理、特点和效果,并对未来Fe0类Fenton试剂氧化反应体系处理有机污染物的发展前景进行了展望。     

Fenton试剂氧化法处理染料结晶废母液

采用Fenton试剂氧化法处理分散橙、分散紫和分散蓝3种染料结晶废母液。研究了H₂O₂加入量、n（H₂O₂）#x02236;n（Fe²⁺）和废母液pH对COD去除率或TOC去除率的影响。对TOC去除反应分段进行了动力学方程拟合,并探讨了反应机理。实验得到的分散橙、分散紫和分散蓝的废母液处理工艺条件：H₂O₂加入量分别为264.4,352.9,441.2mmol/L;n（H₂O₂）#x02236;n（Fe²⁺）分别为20,10,20;废母液pH=3。3种废母液在0~20min和20~120min两个阶段的反应与二级动力学拟合方程的相关性最好。3种废母液经Fenton试剂氧化处理后,部分有机物降解为小分子有机酸,部分有机物完全矿化。     

絮凝#x02014;微波辐射#x02014;Fenton试剂氧化法深度处理焦化废水

用絮凝#x02014;微波辐射#x02014;Fenton试剂氧化法深度处理焦化废水,研究了微波辐射时间、微波功率、FeSO₄加入量、H₂O₂加入量和废水pH对废水处理效果的影响。实验结果表明：在聚合氯化铝加入量为350mg/L、聚丙烯酰胺加入量为12mg/L、废水pH=5、FeSO₄加入量为250mg/L、H₂O₂总加入量为1400mg/L、H₂O₂分3次投加、微波功率为400W、微波辐射时间为60min的条件下,处理后出水的浊度、色度和COD去除率分别为98.59%,97.62%,86.21%。处理后出水澄清透明,COD为50.34mg/L,满足GB50050#x02014;2007《工业循环冷却水处理设计规范》的要求。     

中国2030年CO2排放总量预测研究

我国2005年和2010年CO2排放总量分别为55亿t和81.52亿t,“十五”和“十一五”期间年均增长率分别为11.0％和8.0％.中国2011-2015年、2016-2020年、2021-2025年和2026-2030年GDP年均增长率分别为8％、7％、6％、5％的经济发展模式与对应的能源消费弹性系数分别为0.5、0.5、0.4和0.3的能源发展模式,预测2030年燃煤、燃油和天然气CO2排放量及全国CO2排放总量.提出减少CO2排放总量对策,主要包括：调整能源结构,尽量减少煤炭消费量占能源消费总量的比例,增加石油、天然气和新能源的比例,提高CO2综合利用率,完善CO2管理政策与法律法规等.     

Fenton试剂高级氧化法降解甲基橙模拟废水研究

甲基橙是一种较难降解的有机苯环偶氮染料之一,研究其降解性能对其他染料废水体系的降解研究具有普遍参考价值。通过研究Fenton试剂降解甲基橙过程中的H202浓度、Fe2＋浓度、反应时间和反应体系pH值对甲基橙降解的影响,确定其最佳降解工艺条件为：当甲基橙浓度为20mg／L、pH值为3、Fe2＋浓度为1．5mmol／L、H2O2为32mmol/L时,降解率达到最大值（98．95％）。     

A human health risk assessment of rare earth elements in soil and vegetables from a mining area in Fujian Province,Southeast China

Contaminated food through dietary intake has become the main potential risk impacts on human health. This study investigated concentrations of rare earth elements (REEs) in soil, vegetables, human hair and blood, and assessed human health risk through vegetables consumption in the vicinity of a large-scale mining area located in Hetian Town of Changting County, Fujian Province, Southeast China. The results of the study included the following mean concentrations for total and bio-available REEs of 242.92 ± 68.98 (135.85–327.56) μg g⁻¹ and 118.59 ± 38.49 (57.89–158.96) μg g⁻¹ dry weight (dw) in agricultural soil, respectively, and total REEs of 3.58 ± 5.28 (0.07–64.42) μg g⁻¹ dw in vegetable samples. Concentrations of total REEs in blood and hair collected from the local residents ranged from 424.76 to 1274.80 μg L⁻¹ with an average of 689.74 ± 254.25 μg L⁻¹ and from 0.06 to 1.59 μg g⁻¹ with an average of 0.48 ± 0.59 μg g⁻¹ of the study, respectively. In addition, a significant correlation was observed between REEs in blood and corresponding soil samples (R² = 0.6556, p < 0.05), however there was no correlation between REEs in hair and corresponding soils (p > 0.05). Mean concentrations of REEs of 2.85 (0.59–10.24) μg L⁻¹ in well water from the local households was 53-fold than that in the drinking water of Fuzhou city (0.054 μg L⁻¹). The health risk assessment indicated that vegetable consumption would not result in exceeding the safe values of estimate daily intake (EDI) REEs (100−110 μg kg⁻¹ d⁻¹) for adults and children, but attention should be paid to monitoring human beings health in such rare earth mining areas due to long-term exposure to high dose REEs from food consumptions.