可见光催化剂BiVO_4 降解废水中直接耐酸大红4BS

以直接耐酸大红4BS模拟染料废水为目标污染物,研究了BiVO_4对直接耐酸大红4BS(简称4BS)的吸附效果以及废水初始质量浓度、废水pH和BiVO_4的加入量对光催化降解效果的影响.实验结果表明:当废水初始质量浓度为40 mg/L、废水pH为6.38、BiVO_4加入量为1.0 g/L时,4BS的降解率可达98.9%;BiVO_4重复使用5次后4BS的降解率可达80.0%以上;COD的变化趋势说明4BS被催化剂吸附和光催化降解的过程是循序渐进的.     

某电镀厂污泥酸浸除杂提磷试验

探讨了武汉某工业园电镀厂污泥酸浸、除杂提磷的工艺及条件。当H2SO4（浓度为72％）用量为4mL/g污泥,在液固比为5：1,常温搅拌浸出时间为1h,用碱液调节浸出液pH为4后沉淀1h,过滤,磷的浸出率为86％,铁的沉淀率达到94．2％,除铁后的浸出液进一步用NH4HCO3净化,并制取磷铵产品,总养分（N＋P2O5）为52％。产品达到国家合格品的标准。     

A failure analysis of fillet joint cracking in an oil storage tank

This paper has studied failure of an oil storage tank. During operation, several cracks were observed at the fillet weldment between reactor shell and annular plates in the bottom of oil storage tank. Extreme stresses in the structure during its operation were determined taking into account shape and geometry imperfections as well as corrosion influence. Both reactor shell and annular plates are made of carbon steel (SM53C). In this study, in order to identify the causes for the fillet weldment cracking, failure analysis such as fractography, tensile test, hardness test, corrosion test(SSRT), chemical analysis was performed. The failure of oil storage tank is the result of the combined and synergistic interaction of mechanical stress and corrosion reactions. Although cracks were initiated by corrosion, failure was generated by propagation of crack caused by stresses concentration. It was recommended that (1) the local stresses be reduced by improved weld toe geometry, and (2) the reinforcement be used in order to avoid failure by stresses concentration.     

Performance of a full-scale biofilm system retrofitted with an upflow multilayer bioreactor as a preanoxic reactor for advanced wastewater treatment

To enhance nitrogen removal in an existing microbial contact oxidation (MCO) system with a treatment capacity of 900 m3/d, an upflow multilayer bioreactor (UMBR) was chosen as a preanoxic reactor for the removal of organic matter and nitrate. The removal performance of the retrofitted plant was evaluated during the startup phase at a low temperature in winter. The high removal (>80%) of organic matter and suspended solids in the UMBR provided stable nitrification conditions in the MCO system, as a result of the substantial reduction in organic matter and solids loaded onto the MCO system. This treatment system showed a stable nitrogen removal efficiency of 75.3%, even in the low temperature range 7 to 10 degrees C. Phosphorus was completely removed by chemical precipitation. Production rates of excess sludge, as a function of the loads of influent flowrate and biological oxygen demand (BOD), were 0.022 kg dry solid/m3 wastewater and 0.132 kg dry solid/kg BOD.     

再生水做景观用水使用含氯消毒剂消毒的副产物及安全性

再生水消毒后主要作为城市杂用水利用,消毒副产物及其毒性的研究非常重要.在浓度为 5～8 mg/L 的消毒剂(ClO2、HClO)量下,灭菌率能够达到 100%.2 种消毒体系均产生少量ClO2-、ClO3-和CHCl3,对检验用水生生物未产生毒性.适当的选择消毒剂浓度,控制反应条件,能够实现再生水的安全回用.     

TOC分析仪在化学有机污染物中的监测与应用

将等分的环境水样分别注射到总有机碳分析仪中的TC和IC反应管内,在高温炉900℃和低温炉150℃的工作条件下使其充分氧化为CO2和H2O后,将生成的CO2分别导入非分散红外检测器中,测定出总碳TC和无机碳IC的浓度.依据TC和IC的计量值,获得TOD的测定量.该法与CODCr的测定环境水样结果比较,TOC准确度实验结果为0.87%～0.94%的相对误差,完全满足国标样品标准,精密度实验中TOC的标准偏差小于0.25,而COD标准偏差为0.53～0.55,准确度与精密度都令人满意.能适合于环境水样中有机污染物的快速监测.     

有毒物质低剂量刺激作用的研究进展

有毒物质低剂量刺激作用(hormesis)是一个有争议的毒理学问题.本文综述了hormesis的研究进展、关键学术问题以及可能的作用机制,并对有关hormesis的机理研究与环境内分泌干扰物研究和风险评价理论及方法之间的关系进行了讨论,提出了其中存在的关键科学问题和可能的研究方向.     

浅论经济、社会与环境三效益的矛盾与统一

阐述了经济效益、社会效益与环境效益之间的相互对立统一的辨证关系，从概念和内涵对其矛盾与统一进行了分析，从其相互关系及综合评价中说明了存在的矛盾问题及解决的方法，只有运用可持续发展的理论改变传统的发展观、自然观，人类就一定能够与环境和谐共存，达到经济、社会与环境三效益的结合与统一。     

水体腐殖酸及其络合物 Ⅱ.蓟运河腐殖酸与汞的络合作用

蓟运河及其入渤海口处水及底泥中的腐殖酸已经提取并且进行了物化表征。本文用凝胶过滤技术研究了它们与汞的络合作用,测定它们对汞的络合容量为0.85—2.10m molHg/gHA(FA)(171.2—420.3mgHg/gHA);计算了腐殖酸汞络合物的表观稳定常数并比较了用各种浓度表示方法所计算的表现稳定常数。另外,合成了蓟运河腐殖酸汞络合物并粗测了其溶解度。根据蓟运河水体中腐殖酸的含量,可以认为,腐殖酸汞是该河中汞的主要存在形态,并且大部分以可溶态存在于表层水及间隙水。     

氨氧化细菌的富集培养及影响因素的研究

采用间歇培养方式,对富集氨氧化细菌的过程进行了研究,并探讨了温度、初始pH值、DO、碱度、进水氨氮浓度对短程硝化作用的影响.实验发现:氨氧化细菌富集完成后,氨氧化速率达到22.8 mg/(L·h),亚硝酸盐积累率在80％左右,氨氧化细菌的数量可提高至富集前的32.6倍.此外,对影响因素的研究发现,当温度30℃、pH=8.5、DO=0.5 mg/L、HCO3-/NH4+-N(摩尔比)=1.67、进水氨氮小于400 mg/L时,有利于实现短程硝化.