碱矿渣水泥基铬渣固化体的性能研究

使用碱矿渣水泥基材料对含铬废渣进行了固化研究，并力图使固化体能够用作建材制品。结果表明，用碱矿渣水泥基材固化铬渣是可行的，固化体抗压强度达到了５０ＭＰａ以上，且具有良好的抗渗性能和较低的六价铬离子浸出率，能够用作建筑材料。     

利用成组生物测试评估某城市典型污水处理工艺

设计了一组基于生物标记物的生物测试方法,并用于评价某城市4个典型污水处理工艺对水中痕量有毒有机物的去除效果.测试方法包括检测芳烃(Ah)受体效应物质生物毒性的EROD(7-乙氧基-3-异吩噁唑酮-脱乙基酶)试验、类雌激素效应物质的重组基因酵母生物毒性试验和遗传毒性物质的SOS/umu试验.结果表明,4个典型的城市污水处理工艺对Ah受体效应物质、类雌激素效应物质和遗传毒性物质都有一定的去除效果,其中A2/O处理工艺对3类物质的去除效果最明显;空气曝气活性污泥工艺对直接遗传毒性物质的去除效果较好,但对Ah受体效应物质的去除效果一般,倒置A2/O处理工艺和氧化沟处理工艺也能够较好地去除这3类物质,两种处理工艺效果相当.采用成组生物标记物方法可以对城市污水中的痕量有毒有机物进行毒性筛选或测试,适用于水处理工艺的风险评价.     

Removal of tetracyclines,sulfonamides, and quinolones by industrial-scale composting and anaerobic digestion processes

This study evaluated and compared the removal of antibiotics by industrial-scale composting and anaerobic digestion at different seasons. Twenty compounds belonged to three classes of widely used veterinary antibiotics (i.e., tetracyclines, sulfonamides, and quinolones) were investigated. Results show that of the three groups of antibiotics, tetracyclines were dominant in swine feces and poorly removed by anaerobic digestion with significant accumulation in biosolids, particularly in winter. Compared to that in winter, a much more effective removal (>?97%) by anaerobic digestion was observed for sulfonamides in summer. By contrast, quinolones were the least abundant antibiotics in swine feces and exhibited a higher removal by anaerobic digestion in winter than in summer. The overall removal of antibiotics by aerobic composting could be more than 90% in either winter or summer. Nevertheless, compost products from livestock farms in Beijing contained much higher antibiotics than commercial organic fertilizers. Thus, industrial composting standards should be strictly applied to livestock farms to further remove antibiotics and produce high quality organic fertilizer.     

工业园区和城区VOCs组成及化学活性的空间差异对清远大气臭氧污染分布的影响

工业化与城镇化交替演进使珠三角及其周边地区土地利用类型较为复杂。快速的城市化进程使城市建成区与大量村镇工业园区互相交错。这种变化势必会增加挥发性有机物(VOCs)在组分构成和空间分布上的复杂性,并对臭氧(O₃)污染的时空变化产生影响。为厘清这种排放的空间异质性特征及其对O₃污染分布的影响,分别选取可以代表清远市典型工业园区和城市建成区的站点开展观测研究。结果表明:工业园区和城市建成区VOCs浓度水平和污染特征有较大的空间差异,其中代表村镇工业园区的龙塘站VOCs日均浓度为30.42×10^-9,高于代表城市建成区的技师学院站(17.32×10^-9)。龙塘站二甲苯和甲苯的臭氧生成潜势(OFP)比技师学院站高57.6×10^-9,且该值相当于技师学院站排名前10位物种OFP的总和。气象分析表明:2个站点之间并非彼此的上、下风向,而是共同受到局地气团的影响。源解析结果表明:源排放是造成这种空间异质性的内因,其中交通源对技师学院的贡献更高,而工业相关排放源对龙塘的贡献更高。该研究进一步比较了周边站点O₃时间序列的一致性,并模拟2个站点的O₃生成速率。研究发现O₃在局地范围内变化较小,高VOCs排放的地点对局地O₃有较高的贡献,局地内不同地点的O₃生成过程也存在较大差异。据此,笔者提出O₃污染防控建议:短期内可通过技术手段和观测数据发现O₃污染的重要贡献点,并进行针对性的"散乱污"清理整治和涉VOCs行业综合整治,长期看应科学合理规划城市发展布局和产业布局,预留城市通风廊道,以有效减少O₃污染。     

产富马酸酶菌种筛选及固定化细胞生产L-苹果酸转化条件研究

从土样中筛选得到２０支可将富马酸转化为Ｌ－苹果酸垢细菌菌株。经摇瓶复筛,得到一株富马酸酶活力较高的ＺＧ－４菌株。以改性ＰＶＡ为载体,制备得到固定化细胞。其较佳转化条件为：１经ｍｏｌ／Ｌ Ｎａ２Ｆｕ为底物,ｐＨ７．０,４０转化。固定化细胞经胆酸ρ＝４ｇ／Ｌ或ＴＰＣρ＝０．６ｇ／Ｌ预处理后,可有效抑制琥铂酸副产物的生成。添加没食子单宁ρ＝１ｇＬ,可使富马酸酶比活力达１．９５ｍｍｏｌ ｇ＾－ｈ＾－。固定     

基于生物膜模型的脉冲生物滤池硝化效果模拟

针对脉冲生物滤池的硝化功能,依据物料衡算方程、Fick第一定律构建生物膜传质子模型以及简化的ASM3模型,建立生物膜反应子模型。以Matlab软件为平台编程,模拟在沿脉冲生物滤池水流方向上基质浓度,并依据实测值和参数灵敏度进行分步校正。实测和模拟结果均表明:COD、NH+4-N、NO-2-N的去除主要集中在脉冲生物滤池的中上部、中部、下部,COD和氨氮去除率分别为45%、50%。当改变有机负荷和布水周期时,氨氮去除率随有机负荷的增大而减小,随布水周期的增大而增大。     

Altitude dependence of polychlorinated biphenyls (PCBs) and polybrominated diphenyl ethers (PBDEs) in surface soil from Tibetan Plateau, China

Remote mountain areas besides high latitude regions are beginning to receive increased attention in studying the transport and behavior of persistent organic pollutants (POPs). In the present work, surface soil samples were collected from the Tibetan Plateau, the highest plateau in the world which includes the northern slope of Mt. Qomolangma, to investigate the levels and trends of polychlorinated biphenyls (PCBs) and polybrominated diphenyl ethers (PBDEs) along the altitudinal gradient. The average PCB and PBDE concentrations were 185.6 ng kg⁻¹ dry weight (dw) (range 47.1–422.6 ng kg⁻¹ dw) and 11.1 ng kg⁻¹ dw (range 4.3–34.9 ng kg⁻¹ dw), respectively. Regression analysis between the log-transformed TOC-normalized concentrations and the altitudes of the sampling sites showed two opposite trends with regard to altitude dependence: negative relationship with altitude below about 4500 m followed by a positive altitude dependence above this point. Considering minimum anthropogenic activities and very sparse precipitation in the north of Himalayas, the trends above 4500 m imply that the significant altitude dependence of these two groups of POPs were irrespective of pollution sources, but could be predicted by the global distillation effect involving cold condensation in high altitude mountain areas. Increasing levels of heavier congeners were found in higher altitude sites, although the lighter congeners were the main contributors to the total amount, suggesting that less volatile congeners seem to become enriched easier than those more volatile at higher altitudes in this region.     

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.     

长江,嘉陵江重庆段水环境容量研究

根据特定的水环境容量定义，推导出计算长江嘉陵江重庆干流段和城区段水任人唯贤容量的数学模型，并对计算条件进行了叙述，同时对计算出的水环境容量对空分布也作了较详细的分析。