多孔孔板水力空化反应器的水力特性

设计不同孔分布的孔板空化反应器,通过测定空化数及.OH产生量,研究多孔孔板水力空化反应器空化特性,为高性能多孔孔板水力空化反应器的设计奠定基础。实验结果表明,空化数随孔板孔径的增加、入口压力的减小和溶液温度的升高而增大;.OH产生量随孔板孔径的减小和运行时间的增加而增加,随入口压力和溶液温度的升高先增加后减小。结果表明,多孔孔板水力空化反应器的水力空化效果与孔板结构及操作条件有关。     

Binding of the veterinary drug tetracycline to bovine hemoglobin and toxicological implications

Tetracycline (TC) is a widely used veterinary drug in animal breeding and fishery. Because of its low bioavailability, the TC residue extensively exists in the environment (e.g. soils, lakes and rivers), which can enter the human body, being potentially harmful. Hemoglobin (Hb) is a protein responsible for oxygen carrying in the vascular system of animals. The aim of this study was to investigate the interaction of bovine hemoglobin (BHb) with TC through spectroscopic and molecular modeling methods. The experimental results revealed that TC can interact with BHb with one binding site to form a TC-BHb complex, mainly through van der Waals interactions and hydrogen bonds. The UV-visible absorption, synchronous fluorescence, and circular dichroism (CD) results revealed that the binding of TC can cause conformational and some microenvironmental changes of BHb, which may affect BHb physiological functions. The synchronous fluorescence experiment disclosed that TC binds into BHb central cavity, which was verified by molecular modeling study. The work contributes to clarify the molecular mechanism of TC toxicity in vivo.     

海水及浓海水吸收二氧化硫

采用鼓泡法研究了海水及浓海水对二氧化硫的吸收效果,并考察了吸收液温度、气体流量、盐度及碱度等因素的影响.结果表明,相同条件下,浓海水对二氧化硫的吸收能力较海水明显提高,且温度越高浓海水优势越明显,气体流量为200 mL/min,二氧化硫浓度为3 140 mg/m3,25℃时,浓海水的穿透时间较原海水延长20 min,60℃时则延长30 min.相同碱度条件下,盐度的增加对海水吸收二氧化硫无明显影响;而在相同盐度条件下,碱度的增加可显著提高海水吸收二氧化硫的能力.     

制药废水的厌氧生化性评价及UASB处理

为了处理山东某一药厂的高浓度有机废水,首先采用间歇式实验对山东某一制药厂各主要车间生产废水及综合废水进行厌氧可生化性评价。然后以此为基础,采用两级中温UASB,以某一时期排放的厂区综合废水为处理对象,通过缩短HRT,考察在COD容积负荷的逐步升高下,反应器处理效果的变化。进水COD稀释至10 000 mg/L左右,p H维持在6.8到7.1。在单级UASB最大工程设计容积负荷6 g COD/(L·d)的条件下,经过两级UASB的串联处理,总COD的去除率能达73.5%,出水COD能基本稳定在2 600 mg/L。在这个系统运行时期,产气稳定,出水p H值稳定在7.4到8.0之间,VFA在500 mg/L以下。实验结果表明,两级UASB处理该制药厂废水是可行的。     

李氏禾人工湿地净化Cr(Ⅵ)污染水体的性能研究简

利用湿生铬超富集植物李氏禾构建的三段式波形潜流式人工湿地,研究了湿地系统对Cr（Ⅵ）污染水体的净化效果。结果显示,李氏禾湿地系统对Cr（Ⅵ）污染水体的净化效果明显好于无植物的对照。当进水Cr（Ⅵ）浓度为2.50 mg/L时,李氏禾湿地系统出水Cr（Ⅵ）浓度显著低于对照,说明李氏禾在湿地系统净化Cr（Ⅵ）污染水体中发挥了重要的作用。当进水Cr（Ⅵ）浓度超标150倍（7.50 mg/L）时,李氏禾湿地系统出水Cr（Ⅵ）浓度仍可达到国家地表水环境质量标准（0.05 mg/L）,表明李氏禾湿地系统具有很强的Cr（Ⅵ）污染净化能力。沿程Cr（Ⅵ）浓度的变化显示,湿地系统对Cr（Ⅵ）的去除效率随水流方向逐渐降低,Cr（Ⅵ）主要在湿地系统的前两个阶段被去除。     

富含活性氯与Al_(13)水处理药剂对铜氰络合物去除效能

含重金属铜离子与氰离子(CN)的络合物广泛存在于电镀、冶金等工业废水中,是一种较难处理的污染物。富含活性氯和Al13聚合体的水处理药剂(PACC)兼具氧化和絮凝效能,在处理含重金属氰络合物([Cu(CN)3]2-)废水方面具有良好的应用前景。研究PACC与[Cu(CN)3]2-的反应计量学、动力学,考察了pH、反应时间和投药量等影响因素,确定PACC的最佳工作参数。结果表明,PACC可同时实现对CN的氧化和对Cu2+的絮凝,有效去除水中[Cu(CN)3]2-。使用PACC对[Cu(CN)3]2-的无害化处置过程分为2个阶段:CN-首先被氧化成氰酸根(OCN-);然后OCN-被进一步氧化并生成碳酸氢根和氮气,同时所释放的游离态铜离子被絮凝去除。这2个阶段反应的最佳pH分别为11和8,去除1 mol[Cu(CN)3]2-的最佳投药量为9.35 mol Cl2的PACC;在此条件下反应43 min后,其出水中CN-和Cu2+的浓度均达到排放标准(GB21900-2008)要求。     

Algae mediate submerged macrophyte response to nutrient and dissolved inorganic carbon loading: A mesocosm study on different species

Nutrient and dissolved inorganic carbon are two important factors that influence the development and species composition of submerged macrophyte communities in shallow lake ecosystems. Yet little is known about their potential interactive effects on the submerged macrophytes and competition outcome of macrophyte–phytoplankton. We performed a mesocosm experiment to investigate the growth and photosynthetic performance of three submerged macrophytes in relation to phytoplankton/epiphyton with nutrient and bicarbonate enrichment. During the experimental period (42 d), increase in nutrient loading in water column resulted in a substantial burst of phytoplankton and epiphyton growth and increased light attenuation. When combined with nutrient loading, bicarbonate enrichment also resulted in a heavily phytoplankton- and epiphyton-dominated state, although bicarbonate enrichment per se does not cause the phytoplankton and epiphyton growth. However, increase in nutrient loading in water column had significant negative impact on individual performances (growth and photosynthesis) of the three submerged macrophytes and bicarbonate enrichment increased the effect of eutrophication on two dissected-leaf macrophytes (M. spicatum and E. nuttallii). Furthermore, our results also suggest that species-specific photosynthetic performances occurred when submerged macrophytes in an environment with high abundance of phytoplankton/epiphyton. This study highlighted that increase in nutrient loading and bicarbonate in water column is likely to interactively impact both abiotic and biotic properties of a freshwater ecosystem. The interactions of these two factors could select macrophyte species that are able to resist the shading from phytoplankton/epiphyton, making these species more dominant in natural freshwater ecosystems.     

GC和HPLC测定水中苦味酸的比较

建立了气相色谱法(GC)和高效液相色谱法(HPLC)测定水中苦味酸的分析方法,并对2种方法进行比较。GC法检出限为0.000 4 mg/L,线性范围为0.0~0.050 mg/L,加标回收率为92.3%~94.1%,相对标准偏差为4.6%~8.9%。HPLC法检出限为0.02 mg/L,线性范围为0.10~5.00 mg/L,加标回收率为93.7%~96.5%,相对标准偏差为1.3%~2.0%。2种方法相比,GC法灵敏度较高,可用于痕量分析,但操作烦琐,不能有效地将苦味酸与硝基酚类干扰物分离;而HPLC法虽然灵敏度较差些,但简单、快速、稳定性好、准确度高,可有效地将苦味酸与硝基酚类干扰物分离。     

绿色屋顶径流水质监测研究进展

概述了国内外绿色屋顶径流水质监测发展状况,并从绿色屋顶径流收集、降雨场次、监测指标、径流水质和污染物传输的影响因子等方面进行了归纳和总结。基于水量和水质管理,从几何尺寸、土壤类型和厚度、植被和维护等方面阐述了绿色屋顶在城市排水系统中的作用和地位。揭示了绿色屋顶需要开展长期的监测和研究,绿色屋顶径流水质监测逐渐向采样自动化和分析自动化方向发展。     

Dissipation and residue of 2,4-D isooctyl ester in wheat and soil

A simple analytical method was developed to determine the 2,4-D isooctyl ester residue in wheat and soil by gas chromatography coupled with electron capture detector. Using the method, the dissipation and residue of 2,4-D isooctyl ester in wheat field was investigated. The average recoveries of 2,4-D isooctyl ester ranged from 80.1% to 110.0% with relative standard deviations of 2.4% to 16.1%. The pesticide showed a rapid dissipation rate either in wheat seedling or soil, with the half-lives of 1.0 to 3.0 days. The terminal residue results in wheat grain were much lower than the codex MRL (2.0 mg/kg). It could be considered safe to food and environment when using this herbicide for controlling weeds in wheat field.