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1.
球等鞭金藻对5种金属离子的吸附作用研究   总被引:1,自引:0,他引:1       下载免费PDF全文
通过研究球等鞭金藻(Isochrysis galbana)不同生长过程中对5种重金属离子(Cd2+,Cu2+,Zn2+,Pb2+,Cr6+)的吸附作用,探讨了其生长与金属离子吸附的关系,同时比较了其对不同金属离子的吸附能力。结果表明:在生长初期,球等鞭金藻对重金属离子的吸附能力较强,而在对数生长期后吸附能力变弱,其对5种重金属离子的吸附能力依次为:Pb2+≈Cu2+Zn2+Cr6+Cd2+。  相似文献   

2.
Cu^2+,Zn^2+对罗非鱼鳃盖运动的影响   总被引:4,自引:1,他引:4  
本文研究结果表明:(1)水体中含Cu2+和Zn2+的浓度越高,鱼中毒越深,鳃盖运动振幅的增大和频率的减小就越显著。(2)Cu2+/Zn2+混合液对鳃盖运动的影响具明显的协同作用,它的致毒效应分别为单一因子的3~5倍。(3)毒性次序:5×10-6Cu2+/50×10-6Zn2+>2.5×10-6Cu2+/25×10-6Zn2+>5×10-6Cu2+>50×10-6Zn2+(V/V)。(4)频繁的咳嗽反应是Zn2+中毒的主要症状,驱逐反射是Cu2+中毒的主要症状,两者均可作为单一和混合重金属离子污染的敏感生物学监测指标。  相似文献   

3.
为了探讨海带粉吸附剂工业运用的可能性,采用海藻酸钙包埋法对海带粉进行固定,在合适的反应条件下对Ni2+、Cu2、pb2+三种重金属离子进行吸附.采用二级动力学方程、Langmuir方程和Freundlich方程对吸附过程进行模拟.结果显示二级动力学方程能很好地对固定化海带粉吸附剂吸附Ni2+、Cu2+、pb2+过程进行拟合,平衡时的吸附量分别达到0.317 4、0.465 9、0.501 5 mg/g,对应的二级动力学常数为0.128、0.116、0.114 g/(mg·min),即三种离子的吸附速率Ni2+> Cu2+> Pb2+;Langmuir方程和Freundlich方程都能较好地模拟Ni2+、Cu2+、pb2+的吸附过程,根据Langmuir方程Ni2+、Cu2、pb2+的最大吸附量分别达到2.786、13.699、39.063 mg/g,即吸附效果pb2+>Cu2+> Ni2+,该实验对日后开发海藻生物吸附剂并将其大量制成应用产品有一定的意义.  相似文献   

4.
在模拟生态环境条件下研究了铜(Cu2+)、镉(Cd2+)和锌(Zn2+)3种重金属离子对2种海洋饵料微藻(青岛大扁藻(Platymonas helgolandica)和等鞭金藻8701(Isochrysis galbana 8701))的急性毒性效应,分析其对种群增长的影响,并利用透射电镜对微藻亚显微结构的变化进行分析。在实验浓度范围内,2种微藻的种群增长对3种重金属离子的急性胁迫表现出类似的变化趋势,随着胁迫浓度的增加,微藻的相对增长率均呈现出不断下降的趋势;通过比较2种微藻的48hEC50和96h-EC50发现:3种重金属离子的毒性程度为Cu2+Cd2+Zn2+,等鞭金藻8701对重金属胁迫的敏感性高于青岛大扁藻。2种微藻的亚显微结构观察显示,二者的膜结构及细胞核对Cu2+胁迫并不太敏感;与对照组相比等鞭金藻8701的色素体及贮能物质受影响较严重,而青岛大扁藻的叶绿体及淀粉粒受影响较大。  相似文献   

5.
研究了条纹小环藻(Cyclotella striata)对Cu2+和Zn2+的耐受力、吸附率和吸附量的作用规律.结果表明:Cu2+和Zn2+对条纹小环藻的生长影响显著(p〈0.05),随着Cu2+、Zn2+含量的升高,其对条纹小环藻生长的抑制作用增大;当Cu2+和Zn2+的含量分别高于4.00×10-3、0.01 mg/dm3时,其对条纹小环藻的生长几乎没有影响;Cu2+和Zn2+对条纹小环藻生长的半抑制含量分别为0.26、11.17 mg/dm3.Cu2+含量为1.00 mg/dm3和Zn2+含量为50.00 mg/dm3的组合,对条纹小环藻生长的抑制率达72.28%,Cu2+对条纹小环藻的毒性大于Zn2+.条纹小环藻对Cu2+、Zn2+吸附效果良好,当藻细胞含量为2.45×107cells/dm3时,对Cu2+的吸附率为63.00%;当藻细胞含量为1.75×107cells/dm3时,对Zn2+的吸附率为60.52%;条纹小环藻对Cu2+和Zn2+的吸附量分别为9.26 mg/g(21.30×10-9mg/cell)和20.06 mg/g(46.15×10-9mg/cell)时,Cu2+和Zn2+对条纹小环藻不会产生明显毒性.  相似文献   

6.
鼠尾藻对重金属锌、镉富集及排放作用的研究   总被引:5,自引:0,他引:5  
将鼠尾藻(Sargassum thunbergii)暴露在不同质量浓度锌和镉溶液里40 d,以及暴露20 d后,移入自然海水恢复20 d,分析了藻体内金属离子含量的变化。富集实验结果表明,鼠尾藻积累金属离子的量和暴露溶液金属质量浓度正相关、与暴露时间具有线性关系;暴露3 d,藻体的金属离子含量(除了暴露在Cd2+质量浓度为0.1 mg/L处理组)均显著增加;在Zn2+处理组,溶液里Zn2+质量浓度越大,线性关系越显著,而在Cd2+处理组,Cd2+质量浓度5.0 mg/L处理组藻体内Cd2+含量与暴露时间的线性关系则最低。排放试验结果表明,排放20 d后与排放0 d比较,藻体内的金属离子质量浓度均显著降低,但是均显著高于暴露前水平;在Zn2+溶液里,鼠尾藻暴露Zn2+质量浓度0.1 mg/L和Zn2+质量浓度5.0 mg/L 20 d后移入自然海水5 d后,藻体内的Zn2+含量与排放0 d相比显著降低,而在Cd2+溶液里,藻体排放5 d后,藻体内的Cd2+含量与排放0 d相比均显著降低。最终结果表明,鼠尾藻潜在地可作为一种指示生物,用于监测海洋环境重金属污染状况。同时,鼠尾藻对Zn2+和Cd2+具有较强的富集能力,可以利用鼠尾藻修复受重金属污染的海洋水体,尤其是锌的污染。  相似文献   

7.
Cu,Zn和Cd对5种单细胞藻的酶基因表达调控的研究   总被引:2,自引:0,他引:2  
报道了在Cu2 +、Cd2 +和Zn2 +的毒害作用下 ,三角褐指藻 (PhaeodactylumtricornutumBohlin) ,湛江叉鞭藻 (IsochrysiszhanjiangensisHu &Lui) ,绿色巴夫藻 (PaviovaviridisTsengChenetZhang) ,青岛大扁藻 (Platymonashelgolandicavar.TsingtaoensisTsengetT.J.Chang) ,小球藻(Chlorellasp.)等单细胞藻的苹果酸脱氢酶发生了明显的变化。其中 ,不同种类重金属离子对该酶的基因表达作用不同 ,即使是同种离子但浓度不同 ,这种作用也不同。一般情况下高离子浓度抑制了酶基因的表达。低离子浓度促进了表达。但也有例外 ,如Cd2 +(24.53μg/ml)、Zn2 +(24.31,16.21μg/ml)促进三角褐指藻MDH 1座位等位基因的表达量 ;Cd2 +(24.53,12.26μg/ml)促进小球藻MDH 1座位等位基因的表达量。由此可推出 ,重金属离子可以干扰等位基因的表达 ,并在等位酶的活性上表现出来  相似文献   

8.
广东省电白县大放鸡岛滨珊瑚的重金属含量及其意义   总被引:2,自引:1,他引:2  
采用等离子体质谱(ICP-MS)技术,测定了1982-2001年广东省电白县大放鸡岛(111^* 11’E、21^*21’N)滨珊瑚中的Pb、Cd、Cu、Co、Cr、Mn、Ni、Zn重金属元素的含量。结果表明,珊瑚中有高的Ni和Zn含量的平均值,且在1990和2001年Zn的含量高出平均值1.8和2.3倍;1997和1998年,Pb的含量高出平均值3.5和2.3倍;1987年Cu的含量高出平均值1.5倍。这表明珊瑚样品在上述的年段内受到了Zn、Ni、Pb和Cu较显著的污染。其他重金属元素未构成明显的影响。此外,还用多元统计分析的方法,探讨了重金属含量的年际变化率与气候环境和经济环境指标的相关性,以及重金属元素之间的相似性和差异性。  相似文献   

9.
以5日龄中华鳖稚鳖为实验动物,采用静水停食实验法,在水温(27.4±1.3)℃条件下,开展了Hg2+、Cr6+、Cu2+、Zn2+对中华鳖稚鳖的急性毒性和加和等毒性强度联合毒性试验。结果表明,4种重金属离子对中华鳖稚鳖均呈现以蓄积为主导的急性毒发效应,Cr6+、Zn2+对中华鳖稚鳖的急性致毒高峰期明显滞后于Hg2+、Cu2+;4种重金属离子毒性大小依次为Hg2+、Cu2+、Cr6+、Zn2+,其对中华鳖稚鳖96h的半致死质量浓度分别为5.98、16.42、28.90和91.88mg/L;所构建的中华鳖稚鳖累积死亡概率与重金属质量浓度和实验时间之间的数学模型,以及半致死时间-质量浓度回归方程,可作为侦查和分析重金属离子排放时间和致中华鳖稚鳖大量死亡时间的重要计算工具;Hg2+、Cr6+、Cu2+、Zn2+离子两两组合在加和等毒性强度下对中华鳖稚鳖96h联合急性毒性所呈现的致毒特征与离子种类及其毒性强度匹配情形密切相关。  相似文献   

10.
研究了不同的培养方式(CdCl2浓度、胁迫时间、接种藻密度等)下钝顶螺旋藻(Spirulina platensis)的去除Cd的能力。结果表明:随着CdCl2浓度的增大,藻体总吸附量呈递增趋势,其中藻体表面吸附量远远大于细胞内含量,占总吸附量的95%以上。培养96h,藻体总吸附量比培养10d小,但单位藻质量去除Cd的能力却高于培养10d的实验组。在其它条件不变的情况下,接种藻密度对藻体去除Cd的能力影响不大。  相似文献   

11.
High-molecular-weight, nondialyzable polyphloroglucinols from the marine brown algae Ascophyllum nodosum and Fucus vesiculosus (Phaeophyceae, Fucales) chelate the divalent metal ions Sr2+, Mg2+, Ca2+, Be2+, Mn2+, Cd2+, Co2+, Zn2+, Ni2+, Pb2+ and Cu2+ in weakly acidic aqueous solution. Values of the relative selectivity coefficients k have been calculated relative to Mn2+; the ionotropic series with the algal polyphenols are similar to those with catechol and pyrogallol. These studies may serve as a guide for the examination of metal chelation by brown algal polyphenols both in situ and after exudation into seawater.  相似文献   

12.
Tilapia is a common fish species inhabiting inland waters and estuarine regions in Hong Kong and Southeast Asia, and useful for bio-monitoring of metal pollution. Metallothionein (MT) gene expression in fish tissues has been useful to sub-lethal risk assessment as biomarker of exposure to metal ions in fishes inhabiting metal contaminated area. To investigate metal inductions of Tilapia MT gene expression in vivo, Tilapias were injected with different concentrations of heavy metals and tissues were then removed for quantitative PCR assay using mimic PCR methods. All of the metal ions tested (Cu2+, Cd2+, Hg2+, Ni2+, Pb2+ and Zn2+) were able to induce hepatic MT mRNA levels. Renal MT mRNA levels of Cd2+ and Zn2+ treated fish was not induced with significant fold induction, however MT mRNA levels in gills were sensitive to the administrations of these metal ions. These data indicated that Tilapia MT mRNA levels in gills and liver are sensitive biomarker of exposure to various metal ions.  相似文献   

13.
以彩虹明樱蛤养殖壳高优势组(平均壳高为17.35±1.01mm)为实验动物,进行4种重金属离子Hg2 、Cr6 、Cu2 、Zn2 对彩虹明樱蛤的急性毒性和加和等毒性强度联合毒性试验。结果表明,彩虹明樱蛤对重金属的耐药性均随实验时间延长而缓慢降低,4种重金属离子毒性大小依次为Cu2 、Hg2 、Zn2 、Cr6 ,其对彩虹明樱蛤96h的半致死质量浓度分别为0.0554mg/L、0.1099mg/L、2.2605mg/L、19.6277mg/L;Hg2 、Cr6 、Cu2 、Zn2 离子两两组合在加和等毒性强度下对彩虹明樱蛤96h联合急性毒性所呈现的致毒特征与离子间毒性强度匹配情形密切相关。  相似文献   

14.
The purpose of the present study was to elucidate in vitro effects of Hg2+, Zn2+, Ni2+ and Cd2+ on cytochrome P4501A1 (CYP1A1) dependent EROD activities in leaping mullet liver microsomes. Fish captured from the most polluted part of Izmir Bay, had highly elevated EROD activities, and induced CYP1A1 protein levels as determined by Western blotting. Although all of the metal ions caused inhibition of the initial velocity of the reaction, Hg2+ and Cd2+ exhibited much higher inhibitory effect at lower concentrations and they were evidently more potent inhibitors than others. The inhibitor concentration giving 50% inhibition (IC50 values) of Zn2+, Ni2+, Cd2+ and Hg2+ of initial EROD activity were 107, 16, 1.3 and 0.15 micromolar, respectively. Glutathione (GSH) at 0.5 mM final concentration, completely reversed Ni2+ and Cd2+ inhibition of EROD activity indicating the protective action of GSH.  相似文献   

15.
The effects of ten heavy metal cations on phagocytosis of polystyrene latex spheres by hemocytes of the American oyster, Crassostreavirginica, were investigated. Exposure to 1 and 5 ppm Cd2+, 5 ppm Co2+, 1 ppm Cr3+, 1 ppm Cu2+, 0·5 ppm Fe3+, 0·05 ppm Hg2+, 1 and 5 ppm Mn2+, 1 and 5 ppm Pb2+, 1 ppm Sn2+, and 1 and 5 ppm Zn2+ resulted in no alteration of phagocytic ability. However, exposure to 1 ppm Co2+, 5 ppm Cu3+, 5 ppm Cu2+, 1 and 5 ppm Fe3+, 0·1 ppm Hg2+ and 5 ppm Sn2+ resulted in significantly enhanced uptake of polystyrene spheres. Finally, exposure to 0·5, 1 and 5 ppm Hg2+ resulted in inhibition of phagocytosis and increased cell death.  相似文献   

16.
Chaetoceros muelleri Lemmermann was cultured in solution of different concentrations of Cu2 , Pb2 , Zn2 and Cd2 , and in mixtures of any two of them. After 6 days the effect of these heavy metal cations on the growth rate and chlorophyll contents of the diatom were determined and an Opton microscope was used to observe the morphology and size of the cells.The experimental results show that the effects of toxicity of these four heavy metals on Chaetoceros muelleri are: Cu2 >Pb2 >Zn2 >Cd2 . However, the cells did not differ significantly in their morphology and size from the controled ones.In any of the mixed metals cultures, its growth rate came close to and was higher than that of the single metal culture of higher concentration.  相似文献   

17.
利用可口革囊星虫重组铁蛋白富集Pb2+、Fe3+、Cd2+、Cr3+、Cu2+、Mn2+、Sn2+和Zn2+等8 种重金属离子后, 通过透射显微镜和傅里叶红外光谱测定蛋白的超微结构变化和内部基团特性。以 天然的马脾铁蛋白为对照, 观察重组铁蛋白与天然铁蛋白的差别。结果显示, 重组铁蛋白富集Pb2+ 和其它7 种重金属离子后蛋白体积大小与重金属离子种类直接相关。重组铁蛋白相对天然铁蛋白来 说在富集不同种类重金属离子后, 除了非特异性酰胺特征峰和蛋白特征峰外, 还出现一些专门富集 某些重金属离子的特异基团, 如:-CH3、-CH2-、-CH-、-NH-、-SO3-、-COOH、-S=S-和-C-S-C 等。 通过细胞实验进一步验证了铁结合蛋白能够通过富集重金属离子Pb2+来保护小鼠成骨前体细胞 MRC3T3-E1, 使细胞的死亡率明显降低(P<0.05).  相似文献   

18.
为了研究海洋生物污损对船体和海洋工程的影响,作者将热喷涂镀钴基、镍基及含铜氧化钛基膜的船用厚钢板试样片放置在海水中,利用振荡培养箱模拟海洋环境,进行晃片培养。分离纯化镀膜钢片表面上的细菌,研究早期污损细菌的生长规律,通过革兰氏染色、生理生化实验对细菌进行鉴定,伯杰氏系统细菌学手册查证。采用纸片法测定抑菌圈,研究铜、钴、镍3种金属离子对污损细菌的影响,观察不同离子浓度的抑菌圈。研究结果表明:早期海洋污损细菌有G~+芽孢杆菌属(Bacillus)、G~+芽孢乳杆菌属(Sporolactobacillus)、G~+无芽孢杆菌(Bacilli)、葡萄球菌属(Staphylococcus)、G~+无芽孢丝状菌、假单胞菌属(Pseudomonas)6类;其中G~+细菌首先吸附; Cu~(2+)的最佳抑制质量浓度为30 g/L, Co~(2+)的最佳抑制质量浓度为80 g/L, Ni~(2+)的最佳抑制质量浓度为110 g/L。  相似文献   

19.
The tendency of dimethylsulfide (DMS) to form complexes with heavy metal ions in aqueous solutions and the factors that influence it have been investigated. Among five heavy metal ions examined (Cu2+, Cd2+, Zn2+, Pb2+ and Hg2+), only Hg2+ bound significantly with DMS in aqueous solutions in which Hg2+ concentration was increased to much higher levels than that of natural seawater. The complexation capacity of Hg2+ for DMS was influenced by pH and media. The affinity of Hg2+ for DMS was generally lower at high than at low pH, presumably due to the competition of hydroxide ion to form hydroxomercury species. In different solutions, the affinity of Hg2+ for DMS followed the following sequence: ultra-purified water > 35‰ NaCl solution > seawater. It seems apparent that chloride had a negative impact on the complexation of DMS by Hg2+, owing to the competition of chloride with DMS for complexing Hg2+. In addition, the affinity of Hg2+ for DMS in the bulk seawater appeared to be higher than that in the surface microlayer seawater. The tendency of Hg2+ to form complexes with DMS in aqueous solution can be reduced by the presence of 2 mM amino-acid such as glycine, alanine, serine and cysteine, as these ligands give stable mercury complexes. However, the presence of 2 mM acetate in experimental solutions had no significant effect on the complexation of Hg2+ with DMS, even though this ligand has a relatively strong complexing capacity for Hg2+. Although mercury ions appeared to have a strong affinity for DMS, the concentration of mercury in seawater is too low to produce a great effect on the distribution of DMS in oceans.  相似文献   

20.
云贵高原湖泊沉积物─水界面碱度扩散通量研究   总被引:4,自引:0,他引:4  
于1991-1995年间5次在云贵高原泸沽湖,洱海湖和贵州阿哈湖,百花湖的湖心采集沉积物柱芯,界面水和湖水样品,通过其pH值和HCO3浓度剖面及界面碱度扩散通量的研究,首次定量评估高原湖泊界面扩散作用上不体碱度的影响程度,研究结果表明,云贵高原某些湖水寄宿时间对较长,湖水深度相对小的湖泊,界面扩散作用是水体碱度的重要来源之一,湖水寄宿时间较短,深度较小的湖泊,界面扩散对上覆水体的影响可以忽略不地。  相似文献   

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