低速下不同类型机动车暴露声级和最大声级的测定

本文叙述了对低速下不同类型机动车暴露声级 (LAE)和最大声级 (LmaxF)的测试 ,给出了测试结果 ,并对结果进行了讨论     

人工湿地床示踪剂的研究

本文介绍了对适宜于人工湿地床的示踪剂筛选的原则和方法，从四种染料和食盐中，选定食盐作为人工湿地床的示踪剂，并介绍了食盐示踪剂的注入方法和检测系统。     

白龙江中游泥石流排导槽运行现状及防治建议

以白龙江中游泥石流排导槽为研究对象,总结分析了该地区泥石流排导槽的运行现状及存在问题,并分析出现排导问题的主要原因。通过对研究区20条泥石流沟的调查,研究发现该地区排导槽存在因槽体结构或尺寸设计不合理等原因而引起泥石流的漫溢、淤积、槽底侵蚀以及在泥石流的冲刷作用下引起的排导槽基础掏蚀、侧墙侵蚀破坏等问题。对该地区泥石流沟出现的排导问题进行分类发现,泥石流排导槽的排导问题与泥石流沟流域面积有一定关系,淤积情况一般多发生于面积较小的泥石流沟中,而冲刷侵蚀情况则较多发生于面积较大的泥石流沟中。结合实地情况及泥石流排导槽出现的排导问题特点,提出相应的工程防治建议。     

华北典型污灌区有机氯农药残留特征及健康风险评价

在我国华北地区由于水资源的匮乏及农业生产的需要,采用污水灌溉与施用有机氯农药(OCPs)结合的农业管理方式普遍存在。大量OCPs则被引入到当地环境中,进而可能对该地区的居民产生潜在的健康风险。本研究分析石家庄市汪洋沟污灌区OCPs的残留状况,探讨污水灌溉条件下土壤-作物系统OCPs残留对土壤质量影响,并评价经口摄入及皮肤接触两种暴露途径下对人体产生的健康风险。结果表明:汪洋沟污灌区地表水、沉积物、土壤和玉米籽粒中检出了14种OCPs,其平均残留浓度分别为36.5 ng·L~(-1)、62.9 ng·g~(-1)、57.3 ng·g~(-1)和27.0 ng·g~(-1),滴滴涕(DDTs)是其最主要的污染物,占OCPs的73%以上,其次是六六六(HCHs)和甲氧滴滴涕。р,р'-DDT是DDTs的最主要成分,其主要来源于污水灌溉或近期DDTs的使用。γ-HCH是环境HCHs残留的主要成分,其主要来源于林丹的输入和使用。此外,在该地区污灌条件下OCPs残留对土壤中C、N循环及有机S的矿化产生一定的负面影响。研究区OCPs残留对人体产生的非致癌风险和致癌风险均不超过控制标准,但经口摄入所引致的非致癌风险应予以关注,其中р,р'-DDT与γ-HCH为主要风险物质。     

包气带中造纸废水COD天然生物降解作用

通过野外试验和土柱实验,研究了造纸废水渠底部包气带中,天然形成的生化层分布特征及其对ＣＯＤ降解能力和机制．结果表明,包气带中生化层由生物氧化带和生物还原带组成,生化层的发育厚度受包气带厚度控制,当包气带厚度大于１０ｍ 时,生化层发育良好,对ＣＯＤ的降解率达到９７％ 以上．     

Effect of leachate recirculation on the migration of copper and zinc in municipal solid waste and municipal solid waste incineration bottom ash co-disposed landfill

Municipal solid waste incinerator (MSWI) bottom ash was allowed to be disposed of with municipal solid waste (MSW) in landfill sites in the recently enacted standard of China. In this study, three sets of simulated landfill reactors, namely, conventional MSW landfill (CL), conventional MSWI bottom ash and MSW co-disposed landfill (CCL), and leachate recirculated MSWI bottom ash and MSW co-disposed landfill (RCL), were operated to investigate the environmental impact of the co-disposal. The effect of leachate recirculation on the migration of Cu and Zn in the co-disposed landfill was also presented. The results showed that the co-disposal of MSWI bottom ash with MSW would not enhance the leaching of Cu and Zn from landfill. However, the co-disposal increased the Cu and Zn contents of the refuse in the bottom layer of the landfill from 56.7 to 65.3 mg/kg and from 210 to 236 mg/kg, respectively. The recirculation of the leachate could further increase the Cu and Zn contents of the refuse in the bottom layer of the landfill to 72.9 and 441 mg/kg, respectively. Besides these observations, the results also showed that the co-disposed landfill with leachate recirculation could facilitate the stabilization of the landfill.     

混合菌修复石油污染土壤

选取4种从石油污染土壤中分离出的石油降解菌（包括根瘤菌（A）、节细菌（B）、嗜盐菌（C）和芽孢杆菌（D））,对模拟石油污染土壤进行了微生物修复实验。考察了4种菌单独使用时的石油降解率,确定了混合菌的最佳配比和菌群的最优培养条件,并对比了微生物修复前后土壤的各项性质。实验结果表明：4种菌均可提高微生物修复石油污染土壤的修复效果,使用D菌时石油降解率最高;当混合菌的w（A）∶w（B）∶w（C）∶w（D）=12∶2∶21∶65时,在培养条件为混合菌接种量122.0 mL/kg、土壤含水率14%（w）、鸡粪加入量90 g/kg、麦糠加入量150 g/kg和表面活性剂加入量22 mL/kg的情况下,土壤的修复效果最好,40 d后石油降解率达66.95%;经混合菌修复的石油污染土壤,其肥力明显升高,脱氢酶、过氧化酶和脲酶的活性均升高,微生物数量也有明显增加。     

Effects of fifteen PBDE metabolites, DE71, DE79 and TBBPA on steroidogenesis in the H295R cell line

Polybrominated diphenyl ethers (PBDEs) and tetrabromobisphenol A (TBBPA) are brominated flame retardants that are produced in large quantities and are commonly used in construction materials, textiles, and as polymers in electronic equipment. Environmental and human levels of PBDEs have been increasing in the past 30 years, but the toxicity of PBDEs is not fully understood. Studies on their effects are relatively limited, and show that PBDEs are neurotoxins and potential endocrine disrupters. Hydroxylated (OH) and methoxylated (MeO) PBDEs have also been reported in the adipose tissue, blood and milk of wild animals and humans. In the present study, 15 PBDE metabolites, two BDE mixtures (DE71 and DE79), and TBBPA were studied individually to determine their effects on ten steroidogenic genes, aromatase activity, and concentrations of two steroid hormones (testosterone and 17beta-estradiol) in the H295R human adrenocortical carcinoma cell line. Exposure to 0.05 microM 2'-OH-BDE-68 significantly induced the expression of CYP11A, CYP11B2, CYP17, CYP21, 3betaHSD2, 17betaHSD1, and 17betaHSD4, and the expression of StAR was induced by 6-OH-BDE-90 at the three exposure concentrations. Exposure to DE71 and DE79 resulted in dose-dependent trend towards induction, but these effects were not significant. Exposure to 0.5 microM 2-OH-BDE-123 and 2-MeO-BDE-123 resulted in significantly greater aromatase activity. However, none of the compounds affected sex hormone production at the concentrations tested. Generally, OH-BDEs had a much stronger ability to affect steroidogenic gene expression than MeO-BDEs.     

Composting industry under the Chinese municipal solid waste sorting policy: challenges,opportunities, and directions

Environmental Science and Pollution Research -     

氟化工废水处理系统中活性污泥的耐毒性及微生物群落结构特征分析

氟化工废水具有毒性强、有机负荷高、可生化性差及水质成分复杂等特征,采用功能微生物技术降解氟化工混合废水是当前水处理研究的热点问题.本研究以某氟化工企业污水处理厂一期工程活性污泥S1、二期工程活性污泥S2及城市污水处理厂活性污泥S3为对象,研究3种污泥对氟化工混合废水的耐毒性和微生物群落结构特征.通过Strathtox活性污泥呼吸仪测得污泥S1、S2、S3在葡萄糖模拟废水中的最佳呼吸速率分别为(174.00±1.14)、(189.20±1.11)、(134.50±2.30)mg·L~(-1)·h~(-1),表明3种污泥具有初始活性;在氟化工原始废水中平均呼吸速率分别仅为(5.60±0.70)、(8.87±0.97)、(5.83±0.25)mg·L~(-1)·h~(-1),说明氟化工原始废水存在抑制微生物正常代谢的有毒有害物质.通过固相萃取获得的氟化工有机混合废水实验表明,3种污泥最佳呼吸速率分别为(53.02±0.79)、(68.60±0.96)、(38.10±1.06)mg·L~(-1)·h~(-1),与原始废水中的呼吸状况相比,3类污泥的呼吸作用有显著增强,表明3种活性污泥对氟化工有机混合废水有较强的适应性.应用PCR-DGGE技术对3种活性污泥的微生物多样性研究表明,3种活性污泥微生物多样性较为明显,其中,污泥S1的香浓布朗指数达到1.69.通过进一步的切胶克隆测序,成功鉴定出Kineococcus gynurae等6种能够适应氟化工有机混合废水的优势菌种.验证实验证实,污泥S2对初始总有机碳浓度为250 mg·L~(-1)的氟化工有机废水降解率达到70%,表明氟化工原始废水经过脱盐和消除重金属处理后,其可生化性显著增强.上述研究结果为氟化工混合废水高效处理工艺的开发提供了重要理论依据.