生物表面活性剂产生菌犁头霉菌(Absidia orchidis)的筛选及发酵条件优化

采用植物油为唯一碳源,设计选择培养基,从饭店下水道污泥中筛选出生物表面活性剂产生菌.结果分离到12株菌,其中一株能使发酵液的表面张力值从68 mN·m-1降低到34.5 mN·m-1,具有开发潜力,被选出作进一步的研究.该菌株经鉴定为犁头霉菌(Absidia orchidis).通过正交试验对犁头霉菌的培养条件进行优化,其优化培养条件为:植物油3.6 g·L-1,KH2PO412.1 g·L-1,Na2HPO45 g·L-1,(NH4)2SO4 1 g·L-1,NaNO32 g·L-1,酵母浸膏0.1 g·L-1,MgSO4·7H2O 0.15 g·L-1,NaCl 5 g·L-1,CaCl2 0.1 g·L-1,EDTA 1 g·L-1,KI 0.83μg·L-1,H3PO4 0.01μg·L-1,CoCl2·6H2O 0.048μg·L-1,MnSO4·H2O 0.312μg·L-1,Na2 MoO4·2H2O 0.048μg·L-1,ZnCl2 0.287μg·L-1,CuSO4·5H2O 0.125μg·L-1,初始pH值8,接种量6%.发酵70h时可获得生物表面活性剂的最大收获量,此时发酵液中生物表面活性剂的相对浓度达402倍.     

植物修复--大面积低剂量放射性污染的新治理技术

放射性污染是当今难以治理的环境污染问题,对于大面积低剂量的放射性污染,植物修复是种较适用的新型治理技术.系统阐述了植物修复技术的概念与内容,对放射性污染植物修复技术研究现状与进展、植物修复的优缺点进行了重点评述,并对这技术在未来放射性污染治理中的应用与研究提出了建议.     

三峡水库典型支流磷素赋存形态特征及其成因

采用2018年三峡水库低水位期(6月)、蓄水期(9月)和高水位期(12月)对库区内的典型一级支流——香溪河与神农溪回水区水质、水动力及环境因子的监测数据,对比分析了三峡水库内的典型支流在水库不同调度期时水体中磷素的存在形态及成因.结果表明,香溪河与神农溪库湾水体总磷(TP)质量浓度变化范围分别为0.049～0.168m...     

Understanding interactions between urban development policies and GHG emissions: A case study in Stockholm Region

Human-induced urban growth and sprawl have implications for greenhouse gas (GHG) emissions that may not be included in conventional GHG accounting methods. Improved understanding of this issue requires use of interactive, spatial-explicit social–ecological systems modeling. This paper develops a comprehensive approach to modeling GHG emissions from urban developments, considering Stockholm County, Sweden as a case study. GHG projections to 2040 with a social–ecological system model yield overall greater emissions than simple extrapolations in official climate action planning. The most pronounced difference in emissions (39% higher) from energy use single-residence buildings resulting from urban sprawl. And this difference is not accounted for in the simple extrapolations. Scenario results indicate that a zoning policy, restricting urban development in certain areas, can mitigate 72% of the total emission effects of the model-projected urban sprawl. The study outcomes include a decision support interface for communicating results and policy implications with policymakers.

     

NOx attenuation in flue gas by •OH/SO4•--based advanced oxidation processes

Environmental Science and Pollution Research - The combustion of fossil fuels has resulted in rapidly increasing emissions of nitrogen oxide (NOx), which has caused serious human health and...     

Integrated factor analysis of water level variation in geographically isolated ponds

Environmental Science and Pollution Research - Small geographically isolated ponds provide a multitude of ecological functions and services, but water table fluctuations alter the magnitude of...     

生物法-人工湿地组合工艺处理小城镇混合污水研究

为适应小城镇污水处理高效、低耗、管理简单的要求,开展了生物法(水解酸化/生物接触氧化)-人工湿地组合工艺(A/BCO-CW)处理小城镇片区混合污水的研究。结果表明,A/BCO系统在停留时间为3～6 h条件下,对悬浮物和有机物有高的去除效率,COD、BOD5和TSS去除率分别达到63.1%、67.7%和66.2%,避免了人工湿地堵塞和提高处理效率,减少了所需湿地面积44%。全年运行结果表明,在0.30～0.59 m/d水力负荷率下,垂直流-表面流-水平潜流人工湿地组合系统对COD、BOD5和TSS平均去除负荷达9.4、5.1和7.2 g/(m2.d)(42%、71.2%和85.2%);COD、BOD5去除速率常数为74.6±12.1 m/y、166±30.5 m/y,这些数值均处于文献中k值范围的高量程内。A/BCO-人工湿地系统对COD、BOD5和TSS具有好的处理效果,出水水质能够稳定达到《地表水环境质量标准》(GB 3838-2002)的IV类水标准,2种处理方法有效组合起来,所开发的低成本、高效率、可持续运行的城镇废水处理组合系统,将会在实际应用尤其是高有机负荷污水处理中发挥良好效用。     

藻类打捞对水体营养循环的影响及其生态效果研究

富营养化水体中的藻华是氮磷的富集器,太湖打捞藻样中的总氮、总磷、游离磷及有机物含量分别为98.87g/kg、3.25 g/kg、0.21 g/kg和95.65%。在底泥中沉降藻类的矿质化周期随着温度的升高而缩短;且其向上覆水中释放氮、磷的强度具有随水温升高而增强的趋势。但在水层厚/底泥比不同的区域,这种营养物释放强度又存在显著的差异。实验证明,藻类的打捞是一种人工延长食物链去除氮磷等污染物的有效方法。     

Adsorption of arsenic(V) by iron-oxide-coated diatomite (IOCD)

Purposes and aims  

Economically efficient methods for removing arsenic from the drinking water supply are urgently needed in many parts of the world. Iron oxides are known to have a strong affinity for arsenic in water. However, they are commonly present in the forms of fine powder or floc, which limits their utility in water treatment. In this study, a novel granular adsorbent, iron-oxide-coated diatomite (IOCD), was developed and examined for its adsorption of arsenic from water.     

废弃中药渣催化热解制取生物油的研究

利用热重分析仪(TGA)对植物类中药渣的热解特性进行了研究,用Coats-Redfern积分法计算了其热解动力学参数,得出中药渣热解反应符合一级反应动力学方程,其活化能较低,为36.0kJ/mol。考察了热解温度对气体、液体、固体产物的影响,在723K时,液体产物生物油产率最高,为39%。以介孔分子筛SBA-15以及分别负载Al、Sn、Ni、Cu和Mg的SBA-15作为催化剂,研究催化热解对气体、液体、固体产率及生物油组分的影响。研究表明,Al-SBA-15的催化效果较好,液体产率最高,为36%;采用元素分析仪和热值测定仪,得到用Al-SBA-15作为催化剂时生物油的氧质量分数最低,低位热值最高。用GC/MS对生物油组分的分析结果表明,添加Al-SBA-15后,热解产物中脂肪族和芳香族化合物增加,而含氧化合物减少。