泥浆体系中受喹啉污染土壤的生物修复

将受喹啉污染的土壤 (污染量为 1mg/g土)与一定量的水混合形成泥浆 ,通过引入专性喹啉降解菌皮氏伯克霍尔德氏菌(Burkholderia pickettii)进行土壤的生物修复 .结果表明 ,采用引入喹啉降解菌的生物强化技术进行受喹啉污染的土壤的生物修复是可行的 .喹啉降解菌的引入大大加快了喹啉的生物降解过程 .最快只需 6h就可将喹啉完全去除 .考察比较了投菌量 ,泥浆中的含水量及营养元素(N,P)的存在对生物修复效果的影响 .土壤对难降解有机物喹啉的吸附等温线符合弗兰德里希方程 .     

Toxicological effects involved in risk assessment of rare earth lanthanum on roots of Vicia faba L. seedlings

Combined chemical analyses and biological measurements were utilized to investigate potential toxicological effects and possible mechanisms involved in risk assessment of rare earth elements (REEs) on Vicia faba L. seedlings, which were hydroponically cultivated and exposed to various concentrations of lanthanum (La) for 15 days. The results showed that La contents in both the solution and roots increased with the increase of extraneous La, contributing to hormetic dose responses of superoxide dismutase (SOD), catalase (CAT), guaiacol peroxidase (GPX), ascorbate peroxidase (APX) and endoprotease (EP) isozymes activities, and HSP 70 production enhanced at low doses but suppressed at higher doses of La. These physiological responses constituted antioxidant and detoxification systems against La-induced oxidative stress. The elevated La levels also contributed to oxidatively modified proteins, which were most responsible for subsequent cell death and growth retardation of the roots. By combination of hormetic and traditional threshold dose levels, the threshold dose range was deduced to be 108-195 μg La/g dry weight in the roots, corresponding to 0.90-3.12 mg/L of soluble La in the culture solution. It suggests that persistent applications of REEs may lead to potential ecological risk in the environment.     

邻苯二甲酸酯类化合物正辛醇-水分配系数的QSPR研究

采用PM3算法计算邻苯二甲酸酯类化合物(PAEs)的量子化学参数,应用偏最小二乘(PLS)算法建立了PAEs的正辛醇-水分配系数(K_OW)的定量结构-性质相关(QSPR)模型.模型的结果表明,用量子化学参数建立的QSPR模型相关性显著,具有较好的稳健性和预测能力,因此,利用该模型可对其他PAEs分子的lgK_OW值进行初步预测.模型的结果表明,影响lgK_OW的主要量子化学参数是分子总能量TE、相对分子质量M_r、平均分子极化率α和分子生成热ΔH_f.lgK_OW随着M_r和α的增大而增大,随着TE和ΔH_f的增大而减小.     

Distribution of organochlorine pesticides (OCPs) and polychlorinated biphenyls (PCBs) in surface water and sediments from Baiyangdian Lake in North China

Persistent organochlorine compounds, including hexachlorocyclohexanes (HCHs), dichlorodiphenyltrichloroethanes (DDTs) and polychlorinated biphenyls (PCBs) were analyzed in surface water and sediments from Baiyangdian Lake, North China. Total concentrations of HCHs, DDTs and PCBs in surface water were in the range of 3.13-10.60, 4.05-20.59 and 19.46-131.62 ng/L, respectively, and total concentrations of HCHs, DDTs and PCBs in sediments were 1.75-5.70, 0.91-6.48 and 5.96-29.61 ng/g dry weight, respectively. Among the groups of HCHs (sum of α-HCH, β-HCH, γ-HCH and δ-HCH) and DDTs (sum of DDT, DDD and DDE), the predominance of β-HCH, DDE and DDD in water and sediment samples was clearly observed. This observation suggested that β-HCH was resistant to biodegradation and the DDTs had been transformed to its metabolites, DDE and DDD. For PCBs, penta-, hexa- and hepta-chlorinated congeners were the most abundant compounds in the both phases. Furthermore, the partitioning of chlorinated compounds between sediment and water was investigated to understand their transport and fates in aquatic ecosystems. The results indicated that average logs of organic carbon-normalized sediment-water partition coefficients (logK_oc') for OCPs varied between 3.20 and 5.53, and for PCBs, logK_oc' values ranged from 3.19 to 5.57. The observed logK_oc' was lower than their equilibrium logK_oc predicted from linear model, which may be attributed to the solubility enhancement effect of colloidal matter in water phase and the disequilibrium between sediment and water.     

街道地表物的累积与污染特征：以成都市为例

本文研究了成都市区74km~2范围内地表物的累积规律和污染特征.结果表明,街道地表物累积受土地用途影响;地表有机物受人类活动的影响;重金属受城市交通的影响.粒径分布研究发现街道地表物小于360μm的微粒占70％,且各种污染物主要吸附于细小的微粒上.使用地表污染物边坎累积模型计算了街道地表物和各种污染物的累积量.成都市区每天累积地表物达111吨,BOD,达78kg,COD达411kg,克氏氮6kg和总磷2kg.     

高浓度有机废水二相厌氧消化过程特性研究

以填充床生物膜酸化反应器与上流式污泥床反应器（UASB）甲烷化反应器组成的二相厌氧消化装置处理高浓度啤酒废水或合成废水,最大处理能力为32～35kgCOD/d·m³。提出了二相工艺高负荷运行时最低必需酸化率的概念。进水浓度5000mgCOD/L,容积负荷30kgCOD/d·m³时,最低酸化率为28％。对主要操作参数的灵敏度分析表明,操作负荷、酸化率和进水碱度是影响COD去除率的主要操作参数。对二相厌氧消化系统中影响反应器内微生物群系的生态平衡、微生物本征活性和反应器宏观行为的主要因素进行了分类和综合讨论。     

北京气象塔夏季大气O3,NOx和CO浓度变化的观测实验

以北京325m气象塔为观测平台,于2002年夏季进行了大气污染物臭氧(O₃)及其前体物氮氧化物(NO_x)和气象要素加强期的同步观测.对观测资料做了详尽的分析,结果表明:边界层内存在明显的臭氧浓度(用体积分数表示)垂直差异;中午120m高度层存在O₃浓度最大值;低层O₃浓度呈明显的日变化,且昼夜振幅较大;夜间高层(280m)O₃的湍流混合和化学消耗较弱,可维持较高的浓度;局地光化学生成是白天边界层O₃的主要来源;降水天气过程可造成O₃及其前体物浓度的显著变化.     

某淀粉厂废水处理改造工程设计及运行

某淀粉厂在原有处理工艺的基础上增加厌氧UASB及好氧CASS工艺,完善了物化处理+生化处理的最佳工艺流程。运行结果表明:用该工艺处理淀粉废水,其出水水质达到GB8978-1996《污水综合排放标准》二级排放标准。     

苏州工业园区夜间光环境现状分析

为了了解苏州工业园区夜间光环境现状,本文通过对苏州工业园区夜间环境照度、亮度进行测量,对夜间广告与标志灯数量进行调查和统计分析,探讨了苏州工业园区的主要光环境问题,并提出光环境治理的对策和建议。     

生态增益补偿问题探讨——对东西部生态补偿争议的思考

针对生态补偿增益层面理论研究相对薄弱及当前我国大规模生态工程建设中支付主体单一、资金不足的问题,本文分别从法学、经济学、东西部差异三个角度,通过理论与实例分析相结合的方式,论述了东部对西部实施生态补偿的必要性,提出了将区外受益政府和直接受益行业纳入补偿支付主体,生态增益层面不宜对全社会征收生态税,以及暂时不宜实行自我补偿的政策建议。