医疗废弃物焚烧挥发性氯含量与热值测试与估算

通过测定上海某医疗废弃物处置公司设定燃烧工况条件下某时间段内烟气中HC l的平均排放速率,估算出上海地区医疗垃圾废物中的可燃烧转化氯含量在2.33%~2.64%左右;通过测定各较小采样时间段(2 m in)的烟气HC l浓度测定发现批次进料造成烟气中HC l浓度近4倍的波动,通过初步的热平衡估算得到医疗废弃物的热值大致在21.8 M J/kg,得到的结果可为我国医疗废弃物的焚烧工艺设计提供基础依据。     

Provenances of atmospheric dust over Korea from Sr–Nd isotopes and rare earth elements in early 2006

Sr and Nd isotopic composition of pre- and syn-Asian dust (Hwangsa) particles collected from three different water depths at two different offshore sites, western Korea and rare earth elemental composition of syn-Asian dust particles collected from three islands around the Korean Peninsula in late April 2006 were analyzed to interpret their provenance. The dust Sr–Nd isotopic compositions vary spatiotemporally, but they show specific values when the Hwangsa event occurred. Satellite images, airmass backward trajectory modeling, and comparison with Sr–Nd isotopic ratios and rare earth elements compositions of soils and desert sands of northern China all suggest the major source of dust particles for the late April 2006 Hwangsa event to be the Mu Us Desert in northern China. Dust particles of the pre-Hwangsa period include both background dusts and the previous Hwangsa event dust particles, and they are interpreted to have been originated from various arid regions of China such as the Hobq Desert, the Mu Us Desert, and the Taklamakan Desert in different times. Different background dust sources during pre-Hwangsa period in early 2006 resulted from the changing route of the westerlies.     

紫外分光光度法测定水中硫酸盐的探讨

紫外分光光度法测定水中微量硫酸盐,具有简便、快速、灵敏等优点,适用于清洁环境水样的分析,回收率为96％－110％,其分析指标符合水质分析要求。     

Increased urinary 8-hydroxy-2��-deoxyguanosine levels in workers exposed to di-(2-ethylhexyl) phthalate in a waste plastic recycling site in China

Background

Di-(2-ethylhexyl) phthalate (DEHP) is a common plasticizer used in industrial and diverse consumer products. Animal studies indicate DEHP caused developmental, reproductive, and hepatic toxicities. However, human studies of the potential effects of DEHP are limited.

Methods

The exposed site with a history of over 20 years of waste plastic recycling was located in Hunan Province, China. The reference site without known DEHP pollution source was about 50 km far away from the exposed site. In this study, 181 workers working in plastic waste recycling and 160 gender?Cage matched farmers were recruited. DEHP concentrations in water and cultivated soil samples, serum thyroid-stimulating hormone, malondialdehyde (MDA), superoxide dismutase (SOD), urinary 8-hydroxy-2??-deoxyguanosine (8-OHdG), and micronuclei frequency in human capillary blood lymphocytes were analyzed.

Results

Mean levels of DEHP were greater in environment at the recycling site than at reference site (industry wastewater for the exposed: 42.43 ??g/l; well water: 14.20 vs. 0.79 ??g/l, pond water: 135.68 vs. 0.37 ??g/l, cultivated soil: 13.07 vs. 0.81 mg/kg, p?p?p?Conclusions The occupational DEHP exposure might contribute to oxidative deoxyribonucleic acid damage in the male workers.     

Adsorption of sulfamethoxazole on functionalized carbon nanotubes as affected by cations and anions

The environmental risks of antibiotics have attracted lots of research attention, but their environmental behavior is not clear yet. Functionalized carbon nanotubes (CNTs) were used as model adsorbents and sulfamethoxazole (SMX) was used as a model antibiotic to investigate the effect of both cations (Ca²⁺, Cs⁺) and anions (phosphate) on antibiotics adsorption. Various mechanisms (such as electrostatic interaction, hydrophobic interaction, π-π and hydrogen bonds) play roles in SMX adsorption. Cations and anions could “wedge into” these mechanisms and thus alter SMX adsorption. This study emphasized that both increased and decreased SMX adsorption could be observed with the addition of cations/anions, depending on environmental conditions (such as pH in this current study). The net effect is the balance between the increased and decreased effects. The contribution of different mechanisms to the overall antibiotic adsorption on solid particles should be identified to accurately predict the apparent effect by cations and anions.     

Influences of sediment dessication on phosphorus transformations in an intertidal marsh: formation and release of phosphine

This study investigated the effects of sediment dewatering on the phosphorus transformations concerning about the production and emission of phosphine in the intertidal marsh of the Yangtze Estuary. The concentrations of matrix-bound phosphine ranged from 18.62-72.53 ng kg⁻¹ and 31.14-61.22 ng kg⁻¹ within the August and January exposure incubations, respectively. The responses of matrix-bound phosphine concentrations to sediment dessication demonstrate that the production (or accumulation) of matrix-bound phosphine significantly increased with water loss at the start of the emersion incubations. However, further dehydration inhibited the formation of matrix-bound phosphine in sediments. The significant correlations of matrix-bound phosphine with the organic-P bacteria abundance and alkaline phosphatase activities implicate that the production of matrix-bound phosphine within the dessication incubations was linked closely to the microbial decomposition of organic P. The emissions of phosphine generally decreased with sediment dewatering, with the fluxes of 7.51-96.73 ng m⁻² h⁻¹ and 5.34-77.74 ng m⁻² h⁻¹ over the exposure incubations of both August and January, respectively. Also, it is observed that the releases of phosphine during the entire exposure periods were affected not only by its production but also by sediment water and redox conditions.     

长江口区域饮用水源地有机污染特性研究

以南通市为例,对长江口区域饮用水源地53种挥发性有机物( VOCs)、64种半挥发性有机物(SVOCs)、33种农药、20种多氯联苯等有机污染物进行定性、定量检测,选取汇龙镇水厂、如皋水厂、海门长江水厂3个水厂水源地进行r枯水期、平水期、丰水期3个水期的监测.结果表明:(1)VOCs中仅在枯水期有四氯化碳检出,33种农...     

利用响应曲面法研究蓖齿眼子菜克藻效应的环境因子

水生植物的克藻效应受到多种环境因子的影响.利用响应曲面法,对影响沉水植物蓖齿眼子菜对铜绿微囊藻克藻效应的3个环境因子进行实验研究.通过对曲面模型分析,得出蓖齿眼子菜对铜绿微囊藻的藻细胞个数的相对抑制率在温度、光照强度、全盐莒3个环境因子分别为24℃、2 891 lx、4 407 mg/L时达到最大值.曲面模型经过方差分...     

A2/O-MBR工艺处理印染废水中试研究

将平板微滤膜与A2/O工艺结合构建了A2/O-MBR中试系统,探讨了中试系统处理印染废水的效果及稳定性.结果表明,水解酸化可提高印染废水的可生化性,对COD平均去除率达到了43%.系统处理效果稳定,在最佳工况下COD、NH3-H和TN的去除率分别为88%、98%和80%.     

Fenton氧化4-氯酚降解机制研究

为了深入探讨4-氯酚（4-CP）在Fenton氧化体系中的降解机制,利用高效液相色谱（HPLC）等多种手段系统分析了反应过程中Fe2＋、Cl-、氧化中间产物对苯二酚、1,4-苯醌、4-氯邻苯二酚和4-氯间苯二酚的浓度以及氧化还原电位（ORP）的变化规律.研究结果表明,Fe2＋浓度经历了短暂的下降之后迅速上升到接近初始的...