Fe/活性炭多相类Fenton法湿式氧化罗丹明B废水的研究

采用自制的Fe/活性炭（Fe/AC）为催化剂，H₂O₂为氧化剂,组成多相类Fenton试剂催化降解罗丹明B染料废水。实验结果表明,在催化剂加入量为0.8 g/L，H₂O₂体积分数为0.3%,废水pH值为13,反应时间为30 min的条件下,质量浓度为200 mg/L的罗丹明B染料废水的脱色率达100%。反应动力学研究表明,罗丹明B脱色反应近似为一级反应,30℃时反应速率常数为0.02675 min^-1,表观活化能为69.47 kJ/mol。     

Characteristics and transport of organochlorine pesticides in urban environment: air, dust, rain, canopy throughfall, and runoff

Characteristics and transport of organochlorine pesticides (OCPs) in urban multiple environments, including air, dust, rain, canopy throughfall, and runoff water, are explored in this study. Hexachlorocyclohexanes (HCHs) dominated in both air and rain water, and dichlorodiphenyltrichloroethane (DDT) related substances showed a higher affinity to dust. Relatively high concentrations of DDT and dichlorodiphenyldichloroethylene (DDE) in air, rain and dust imply that technical DDT in the environment has been degrading, and there may be unknown local or regional emission sources that contain DDTs in the study area. Source identification showed that DDTs in Beijing urban environments with a fresh signature may originate from the atmospheric transport from remote areas. The ratio of α-/γ-HCH in dust, rain, canopy throughfall and runoff were close to 1, indicating the possible use of lindane. OCPs in runoff were transported from various sources including rain, dust, and canopy throughfall. In runoff, DDTs and hexachlorobenzene (HCB) were mainly transported from dust, and HCHs were mainly from rain and canopy throughfall.     

对酞内酰胺基苯甲酰氯衍生试剂合成的研究

本文对对酞内酰胺基苯甲酰氯的合成方法进行了研究，改进了溶剂的预处理方法，有效地消除了其中的有害杂质。     

CdS-TiO_2/MWCNTs结构表征及其光催化性能

采用溶胶-凝胶法,制备了多壁碳纳米管(MWCNTs)负载的双组分复合半导体光催化剂CdS-TiO2/MWCNTs。通过透射电镜(TEM)、比表面分析(BET)、X射线衍射(XRD)和紫外-可见吸收光谱(UV-vis)等分析方法对光催化剂进行了结构表征,并考察了CdS-TiO2/MWCNTs对甲苯降解的光催化性能。结果表明:纳米活性粒子CdS-TiO2均匀负载于MWCNTs上,比表面积、光吸收阈值和强度增大,活性粒子间以及活性粒子与载体之间具有协同作用,有利于光催化性能的提高,CdS-TiO2/MWCNTs在主波长为254 nm紫外光照射下对甲苯的降解效果较好,去除率可达55.3%。     

微波预处理和微生物联合煤炭脱硫技术初探

将微波技术应用于微生物法煤炭脱硫,研究了煤粉粒径、煤浆浓度、初始pH值、嗜酸氧化亚铁硫杆菌(Acidithiobacillus ferrooxidans)接种量、微波辐照时间、脱硫周期等因素对微波预处理和微生物联合脱硫效果的影响,同时以单纯Acidithiobacillus ferrooxidans煤炭脱硫作对照.在煤样粒径为200目(＜0.074 mm)、煤浆浓度为10%、初始pH为2.5、菌体接种量为10%、微波辐照时间3 min、脱硫周期4 d、温度30℃、摇床转速为160 r/min条件下,微波预处理和微生物联合作用对煤炭中全硫的脱除率可达51.3%.该结果表明,微波预处理和微生物联合煤炭脱硫技术可以大大缩短微生物脱硫周期.该研究结果可为开发新脱硫工艺提供参考.     

UASB处理甲醇废水的实验研究

利用升流式厌氧污泥床(UASB)反应器在中温条件下处理高COD浓度的甲醇废水。当反应器稳定运行,进水COD=36 000 mg/L时,容积负荷可达到70~74 kg COD/(m3.d),COD去除率可以达到95%以上,出水COD2 000 mg/L。通过实验取得的良好实验效果,为利用厌氧技术处理甲醇废水提供了设计依据。     

磁絮凝污水处理装置的设计及实验验证

为了优化设计装置内部的结构,分别使用Fe3O4磁块和NdFeB磁块制作了2台简易装置进行实验。在实验中由于装置的结构和磁系会影响絮凝的过程,因此将磁盘厚度减到了33 mm,提高了单位时间内流体通过磁盘的流量。在实用可行方面,设计了高效率的絮体助卸装置;2块外磁盘只受单边磁力作用因而对其结构做了加强设计;并且设计了独特的磁盘位置调整机构,以便在实验中调整磁盘间距;装置使用变频调速控制能够及时调整磁盘的转速,从而保证分离的效果。在实际实验中验证了该装置的处理效果,经过处理的水体能达到国家三类水质标准。     

Dynamic changes of rhizosphere properties and antioxidant enzyme responses of wheat plants (Triticum aestivum L.) grown in mercury-contaminated soils

A pot experiment was conducted to investigate the dynamic changes in the rhizosphere properties and antioxidant enzyme responses of wheat plants (Triticum aestivum L.) grown in three levels of Hg-contaminated soils. The concentrations of soluble Hg and dissolved organic carbon (DOC) in the rhizosphere soil solutions of the wheat plants were characterised by the sequence before sowing > trefoil stage > stooling stage, whereas the soil solution pH was found to follow an opposite distribution pattern. The activities of antioxidant enzymes in wheat plants under Hg stress were substantially altered. Greater superoxide dismutase (SOD), catalase (CAT) and ascorbate peroxidase (APX) activities were observed in the wheat plants grown in a highly polluted soil than in a slightly polluted soil (with increases of 11–27% at the trefoil stage and 26–70% at the stooling stage); however, increasing concentrations of Hg up to seriously polluted level led to reduced enzyme activities. The present results suggest that wheat plants could positively adapt to environmental Hg stress, with rhizosphere acidification, the enhancement of DOC production and greater antioxidant enzyme activities perhaps being three important mechanisms involved in the metal uptake/tolerance in the rhizospheres of wheat plants grown in Hg-contaminated soils.     

活性黑5脱色菌的分离鉴定及其脱色特性

从改良A2O反应器的厌氧污泥中分离得到1株活性黑5的脱色菌菌株GY-1,经过对其菌落形态、生化特性以及16SrDNA基因序列的分析,该菌株初步鉴定为肠杆菌属(Enterobacter)。考察生长条件对活性黑5脱色的影响,得出该菌株对活性黑5脱色的最佳条件:接种量为8%(体积分数)、初始pH为7.0、温度为35℃。在该条件下,菌株GY-1对不同初始浓度活性黑5的脱色反应过程进行动力学分析,在活性黑5初始质量浓度为25~100 mg/L时符合一级反应动力学特征。     

连续培养酱油曲霉（Aspergillussojae）产微生物絮凝剂的研究

为了利用廉价材料规模化生产微生物絮凝剂，以味精废水作为廉价培养基质，对酱油曲霉的摇瓶连续培养和发酵罐连续培养进行了研究。摇瓶中以5％的接种量进行连续培养，最适温度在30～33℃之间，每6h替换一次新鲜废水培养基，5次替换新鲜废水培养基后最大絮凝率仍达到97．8％。在发酵罐扩大连续培养中以5％的接种量接种后经过9h预培养达到稳定生产絮凝剂后，以4mL／min的补料流量进行连续培养，生产的絮凝剂产量达到2．392g／L，且最大絮凝率为98．1％。生产36h后对发酵系统中菌体进行稀释，使菌体量保持在50—200g／L之间可持续进行生产。