湖泊底泥中蓝藻越冬和复苏行为研究进展

富营养化湖泊蓝藻水华暴发是重大水环境问题.深入了解越冬期间蓝藻在底泥中的活动过程及其习性,为对此阶段采取有效措施抑制蓝藻复苏提供理论依据,为湖泊蓝藻治理提供新思路.综述了越冬期蓝藻细胞形态、活性、藻毒性、上浮能力等变化以及外部条件如温度,光照强度、DO、营养盐等对其复苏的影响,指出现阶段研究中存在的问题,明确未来的研究...     

强化混凝-滤布滤池提升城市河道水感官品质效果分析

为提高城市河道水感官品质,研究了强化混凝沉淀与滤布滤池组合工艺对河道水的处理效果。以PAC为混凝剂,纳米四氧化三铁为助凝剂,在实验室优化条件实验的基础上,设计加工强化混凝-滤布滤池一体机,在苏州姑苏区外城河进行处理规模为2 t·h⁻¹的现场实验,并采用多种分析仪器对进水、沉淀和混凝出水水样进行分析。结果表明,强化混凝滤布滤池一体化装置可以有效去除各项污染指标,显著改善河道水感官品质,装置对色度的平均去除率为67.7%,出水色度为10度;出水平均透明度提升10倍以上,最终出水3.1 m。通过对各个水质指标进行逐一分析并做相关性分析之后发现,影响色度和透明度的主要因素有悬浮固体、CDOM、藻类及叶绿素a,该装置对这些物质均有一定处理效果,因此,能够显著提升感官品质。本研究结果可为沿海城市提高河道水感官品质提供参考。     

脱硫石膏改良碱化土壤种植枸杞的效果研究

利用燃煤电厂脱硫石膏改良盐碱地对于废弃物资源化利用和发展循环经济具有重要意义。选择具有典型代表性的宁夏西大滩碱化土壤,采用两因素随机区组田间实验设计,进行脱硫石膏改良碱化土壤种植枸杞的效果实验研究。研究表明脱硫石膏施用量和施用深度不同,对于降低土壤碱化度、总碱度和pH值,改良土壤碱性的效果不同;脱硫石膏施用量不同,对于促进枸杞枝条和径杆的生长不同。施用量24 000 kg/hm2较48 000 kg/hm2提高枸杞枝条生长量10.5%～18.7%、径杆生长量10.5%～18.7%;脱硫石膏施用量24 000 kg/hm2,施用深度60 cm更有利于提高枸杞红果体积、红果鲜重和产量。脱硫石膏施用量24 000 kg/hm2,施用深度60 cm较未施脱硫石膏提高枸杞红果体积、红果鲜重和产量分别为28.3%、15.0%和37.9%。     

基于人工神经网络的街道峡谷NOx浓度的数值模型研究

通过对反向传播人工神经网络的算法和网络结构的研究,发现拟牛顿算法训练速度较快,能够较好地接近误差目标值,同时建立了包括输入层、隐含层、输出层的人工神经网络三层拓扑结构。通过对街道峡谷人工神经网络的训练,模拟计算了街道峡谷NOx浓度分布值。结果显示,训练误差和测试误差比为1．11,训练样本的模拟值与实测值的相关系数为0．93,测试样本的模拟值与实测值的相关系数为0．87,模拟值与实测值的相关系数均高于显著水平为α=0．05与α=0．01所对应检验性表的相关系数临界值。该模型能够用于街道峡谷污染物浓度的模拟计算,具有较好的泛化能力。     

Effect of first-stage aeration on treatment of domestic sewage in different hybrid constructed wetlands

Environmental Science and Pollution Research - Two sets of hybrid constructed wetlands (HCWs) with the first-stage aeration were used to treat actual domestic sewage in this paper, where the...     

Enrichment and characterization of an effective hexavalent chromium-reducing microbial community YEM001

Environmental Science and Pollution Research - Chromium (Cr) is one of the most widely used heavy metals in industrial processes, resulting in water and soil pollution that seriously threaten...     

Brominated flame retardants in the hair and serum samples from an e-waste recycling area in southeastern China: the possibility of using hair for biomonitoring

Hair samples and paired serum samples were collected from e-waste and urban areas in Wenling of Zhejiang Province, China. The PBDE and DBDPE concentrations in hair and serum samples from e-waste workers were significantly higher than those of non-occupational residents and urban residents. BDE209 was the dominating BFRs in hair and serum samples from the e-waste area, while DBDPE was the major BFRs from the urban area. Statistically significant correlations were observed between hair level and serum level for some substances (BDE209, DBDPE, BDE99, BDE47, BDE28, and BDE17), although the PBDE congener profiles in hair were different from those in the serum. A statistically significant positive correlation between the PBDE concentrations and the working age, as well as gender difference, was observed in e-waste workers. Different sources of PBDEs and DBDPE in three groups were identified by principal component analysis and spearman correlation coefficient. Hair is suggested to be a useful matrix for biomonitoring the PBDE exposure in humans.     

基于破碎处理的家庭厨余垃圾减量及其对下水的影响

在对我国家庭厨余垃圾的组成及性质、污水管道设计、污水处理厂运行状况的调查研究基础上,初步探讨了基于厨房垃圾粉碎机的家庭厨余垃圾减量及其对下水系统的影响。家庭厨余垃圾生成量(湿重)平均为152 g/(人·d),其中易降解的蔬菜水果垃圾占到77.8%。家庭厨余垃圾的COD:TN:TP=400.9:4.7:1,可能导致污水处理厂的总COD、TN、TP和氨氮理论提高量分别为66.70、0.86、0.18和0.43 mg/L,会在一定程度上缓解我国污水处理厂碳源不足的现状。厨房垃圾粉碎机使用后,人均用水最大增加量为1.5 L/(人·d),破碎时间短基本介于1~3.5 min之间。破碎后的厨余垃圾颗粒含水率高,密度略大于水,其在管道中起动的临界流速为0.02 m/s远小于0.6 m/s,故因厨房垃圾粉碎机使用引起的污水管网堵塞的可能性小。     

Threats to China’s Biodiversity by Contradictions Policy

China has among the highest biodiversities in the world, but faces extreme biodiversity losses due to the country’s huge population and its recent explosive socioeconomic development. Despite huge efforts and investments by the government and Chinese society to conserve biodiversity, especially in recent decades, biodiversity losses may not have been reversed, and may even have been exacerbated by unintended consequences resulting from these projects. China’s centralized approach to biodiversity conservation, with limited local participation, creates an inflexible and inefficient approach because of conflicts between local communities and national administrators over the benefits. Although community-based conservation may be an imperfect approach, it is an essential component of a successful future national conservation plan. Biodiversity conservation should be considered from the perspective of systems engineering and a governance structure that combines centralization with community-level conservation. In this paper, we describe China’s complex challenge: how to manage interactions between humans and nature to find win–win solutions that can ensure long-term biodiversity conservation without sacrificing human concerns.     

二级Fenton氧化高浓度有机硅废水研究

采用二级Fenton氧化技术对可生化性差的高浓度有机硅废水进行处理,考察了不同因素对COD去除率的影响,对比了一级氧化和二级氧化的效果。结果表明对于COD为9 600 mg/L的高浓度有机硅废水,pH为3,[H2O2]/[Fe2+]=2∶1为最佳的反应条件,COD去除率随着H2O2的投加量的增大先增大而后减小,每200 mL水样中先投加20%的硫酸亚铁12 mL,然后分2次投加30%的H2O2各4 mL,氧化完成后调整pH值为7~8静止沉淀,COD去除率达89.2%。对于某绝缘电器厂的生产废水经二级Fenton氧化处理后,出水有机物浓度显著降低,可生化性提高,Fenton二级氧化可以作为高浓度有机硅废水的预处理工艺。