锰氧化物-阳离子交换树脂复合材料的制备及其对水中重金属的吸附性能

采用原位沉淀-空气氧化法将锰氧化物负载于大孔强酸性阳离子交换树脂D001上,制备出一种新型锰氧化物-阳离子交换树脂复合材料Mn-D001,并对该材料吸附水中Pb2+、Cd2+、Cu2+的性能进行了深入研究.TEM、XRD以及XPS的分析结果表明,负载的锰氧化物以MnO2的形态存在.基于单一金属离子静态吸附的一元体系实验表明,Mn-D001比D001对Pb2+、Cd2+、Cu2+具有更高的吸附选择性,在高浓度竞争离子Ca2+、Mg2+、Na+共存的情况下,仍能保持较高的重金属去除率;Mn-D001对Pb2+、Cd2+、Cu2+的吸附行为符合准一级动力学模型(R2>0.99)和Langmuir吸附等温线模型(R2>0.99).在温度为303 K时,Mn-D001对3种重金属的饱和吸附容量可分别达到476.19 mg.g-1、243.90 mg.g-1及196.08 mg.g-1,优于原有树脂D001.基于复合重金属离子竞争吸附的二元、三元体系的实验表明,Mn-D001对3种重金属的吸附能力顺序为Pb2+>Cu2+>Cd2+,吸附能力由原有树脂D001以及负载的锰氧化物的性质共同决定.     

Sorption of Triton X-100 on soil organic matter fractions：Kinetics and isotherms

Kinetics and isotherms of Triton X-100 sorption on soil,base-extracted soil(BE),humic acid (HA) and humin (HM) were investigated respectively to get better understanding on characteristics of the surfactant sorptiun onto different soil organic matters(SOMs).It was demonstrated that the kinetics results could be satisfactorily described by the pseudo-second order model.The half of the time to reach equilibrium(t1/2) for different sorbents followed the sequence of soil>HA>BE>HM.Furthermore,the calculated equilibrium sorption capacity(Ceq) was found in the sequence of HA>BE>HM>soil,which agreed well with the experimental results.The isotherms of Triton X-100 sorption on soil and HA could be well described by the S-type isotherm,but BE and HM by the L-type.The isotherms of all the four sorbents were found reasonably fitted to the Langmuir equation.The Kd value,defined as the ratio of Triton X-100 in sorbent and in the equilibrium solution for given concentrations,generally followed the order of HM>HA>soil>BE.Separated HM and HA showed high affinity for Triton X-100,but the HA and HM in soil and BE were tightly bounded by the minerals.Thus,the HA on the soil surface might dominate the sorption,whereas the bounded HM would play a key role upon the surfactants being penetrated inside the soil.     

利用唐鱼雌激素受体构建环境雌激素重组酵母测评系统的研究

利用唐鱼雌激素受体基因片段构建重组酵母,用以筛选环境雌激素类化学物质.实验先将唐鱼雌激素受体terα基因片段插入载体pGADT7中构建表达质粒p GADT7/TERα,同时将雌激素效应元件(ere)片段插入pMP206载体中构建报告质粒pMP206/ERE-Lac Z;然后把表达质粒和报告质粒共转化到酵母AH109中,经筛选成功构建了由唐鱼雌激素受体调控的表达lac Z基因的重组酵母AHpTERα/ERE.结果表明,所构建的重组酵母AHpTERα/ERE在不同浓度17β-雌二醇(E2)的诱导下,β-半乳糖苷酶的活性呈现出明显的剂量-效应关系,其EC50为(0.521±0.700)nmol·L-1.与DMSO对照组相比,重组酵母在17β-雌二醇诱导下有明显的β-半乳糖苷酶活性增强的现象.在不同浓度17α-乙炔基雌二醇(EE2)、壬基酚(NP)及其混合物、双酚A(BPA)、17β-雌二醇(E2)(阳性对照)的诱导下,重组酵母均呈现出剂量-效应关系,且灵敏度大小为E2EE2NPBPA.结果表明,本研究成功构建了重组基因酵母测评系统,初步判定该重组酵母可应用于环境雌激素的筛选.     

Completely autotrophic nitrogen-removal over nitrite in lab-scale constructed wetlands: evidence from a mass balance study

A mass-balance study was carried out to investigate the transformation of nitrogenous pollutants in vertical flow wetlands. Landfill leachate containing low BOD, but a high concentration of ammonia, was treated in four wetland columns under predominately aerobic conditions. Influent total nitrogen in the leachate consisted mainly of ammonia with less than 1% nitrate and nitrite, and negligible organic nitrogen. There was a substantial loss of total nitrogen (52%) in one column, whereas other columns exhibited zero to minor losses (<12%). Net nitrogen loss under study conditions was unexpected. Correlations between pH, nitrite and nitrate concentrations indicated the removal of nitrogen under study conditions did not follow the conventional, simplistic, chemistry of autotrophic nitrification. Through mass-balance analysis, it was found that CANON (Completely Autotrophic Nitrogen-removal Over Nitrite) was responsible for the transformation of nitrogen into gaseous form, thereby causing the loss of nitrogen mass. The results show that CANON can be native to aerobic engineered wetland systems treating wastewater that contains high ammonia and low BOD.     

哈尔滨市采暖与非采暖期大气颗粒物污染特性研究

为了研究采暖对哈尔滨市大气颗粒物环境特征的影响,分别在采暖前、采暖期和采暖后采集TSP、PM10和PM2.5.分析了3种粒径颗粒物在采暖期和非采暖期的浓度变化特征以及粒径分布特征,并做了颗粒物的化学成分分析,包括20种无机元素和两种碳成分.结果表明:TSP和PM10在12月、1月、3月和4月均超标,而在非采暖期均达到国...     

Pollution characteristics and toxic effects of PM1.0 and PM2.5 in Harbin,China

Environmental Science and Pollution Research - In 2019, PM2.5 and PM1.0 samples were collected in Harbin City, Heilongjiang Province, China, to research their mass concentration, number...     

红豆杉培养细胞紫杉醇的分离及鉴定

红豆杉培养细胞紫杉醇的分离及鉴定甘烦远，郑光植，彭丽萍，沈月毛（中国科学院昆明植物研究所昆明６５０２０４）关键词红豆杉；紫杉醇；细胞培养；分离鉴定ＩＳＯＬＡＴＩＯＮＡＮＤＩＤＥＮＴＩＦＩＣＡＴＩＯＮＯＦＴＡＸＯＬＦＲＯＭＣＵＬＴＵＲＥＤＣＥＬＬＳＯＦ...     

氯氰菊酯对唐鱼肝和鳃组织超氧化物歧化酶(SOD)活性的影响

在实验室条件下采用静水法生物测试,研究了氯氰菊酯对唐鱼(Tanichthys albonubes)的急性毒性及其对肝和鳃组织超氧化物歧化酶(SOD)活性的影响。结果表明,氯氰菊酯对唐鱼24、48、72、96h半致死浓度分别为27.27、15.94、10.13、6.61μg·L-1;经1、3、5μg·L-1浓度处理6、12、24、48、72h,结果显示唐鱼SOD在低浓度氯氰菊酯的胁迫下呈现明显的浓度效应关系,将唐鱼SOD作为农药等污染物的污染指标具有重要的应用前景,为安全使用农药和防止水体污染提供有益的理论参考依据。     

100 MW锅炉NaOH颗粒生成的数值模拟

煤粉燃烧过程中矿物质的气化、成核、凝结等过程是炉膛中亚微米颗粒形成的主要途径。本文运用CFD软件针对某100 MW锅炉内NaOH颗粒形成进行了数值研究,计算得到了炉内的温度分布、氧浓度分布和亚微米颗粒数量浓度和质量浓度分布。结果显示,亚微米颗粒的生成数量与温度具有强烈的相关性,温度较高的区域亚微米颗粒数量浓度较大,温度较低的区域则较小;而在炉膛的高温区内,NaOH颗粒的质量浓度并不是最高,而是最低,同时随着炉膛高度的增加,NaOH颗粒的质量浓度逐渐增加。计算结果为今后数值研究燃煤过程中亚微米颗粒的形成与演化奠定基础,为研究温度等燃烧条件对亚微米颗粒形成的影响、抑制其排放等方面提供了一种有效研究手段。