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1.
研究了金鱼( Carassiusauratus L.) 在铅暴露实验中的铅吸收过程及鱼鳃分泌物的自身保护作用、水相Pb2+ 的鳃吸收机理以及分泌粘液对铅的络合作用.结果表明,金鱼因铅暴露导致粘液分泌量增加.结合到鳃上的铅与水相Pb2+ 活度关系可用Langmuir 吸附等温式表述.据此估算的最大结合量为0-9424 m mol/kg(干重) .非常接近1 的Hill 常数(1-012)说明金鱼鳃上仅有一种类型的Pb2+ 结合位点.平均每尾金鱼鳃上Pb2+ 的结合位点数达1-62 ×10- 5 m mol,结合的条件稳定常数(log KPb鳃) 为4-8 .血液铅含量与鳃铅含量间呈显著线性关系.金鱼吸收Pb2+ 的主要过程为:Pb2+ 结合到鳃上,其后被动扩散或载体转运穿过鳃上皮,进入血液循环.  相似文献   

2.
鱼对不同形态铅的吸收   总被引:7,自引:0,他引:7  
研究了水中铅游离态和各种无机络合态之间的分布特征,探讨了鱼鳃分泌物的络合性能及其对形态分布的影响。结果表明:在没有天然有机配位体的体系中,Pb主要以PbCO^-3,Pb(OH)^+,Pb(OH)^02,Pb(CO3)62-2和Pb^2+形态存在。金鱼粘液分泌与铅暴露量成正相关关系。  相似文献   

3.
金鱼(Carassius auratus)对颗粒态镉的鳃吸收   总被引:8,自引:0,他引:8  
采用水相平衡态镉浓度不变(0.01mg/L),增加水铝矿颗粒吸附态镉暴露的实验方法,研究了金鱼(Carassius auratus)对颗粒态镉的鳃吸收,结果表明,鳃中镉含量均随态镉暴露浓度增加,且镉/铝含量比明显高于水相,从而证实了颗粒态镉的鲁鳃吸收有效性,金鱼鳃吸收态镉的主要过程是:随水流流经鳃表面的颗粒态匐会着在鳃表粘液上,在鳃部微环境下,吸附的镉发生解吸而被鳃部细胞吸收,颗粒物及未被吸收的镉在鳃丝表面短暂停留后与脱落粘液一起随水流从鳃部排出。  相似文献   

4.
土壤中重金属镉锌铅复合污染的研究   总被引:52,自引:2,他引:52  
采用吸附与解吸实验及盆栽试验,研究了在重金属镉、锌、铅复合污染条件下,棕壤对重金属的吸附、解吸规律,以及菠菜吸收重金属的特点。结果表明:棕壤对铅、锌的吸附分别符合Langmuir、Freundlich方程,对镉的吸附用Langmuir、Freundlich及Temkin方程回归都不显。重金属被吸附后的解吸率顺序为:Zn〉Cd〉Pb。Pb^2+与吸附位结合的牢固程度较单一污染时大,而Cd^2+和Z  相似文献   

5.
以三乙烯四胺,环氧氯丙烷和氯乙酸为原料,合成了氨基酸结构的螯合树脂,并研究了Cu^2+,Pb^2+,Ni^2+,Zn^2+的吸附性能。结果表明,该树脂对Cu^2+,Pb^2+,Pb^2+,Ni^2+比对Zn^2+具有良好的吸附性能,其吸附量可达1.40,,1.39,1.20及0.4mol/g。  相似文献   

6.
水系沉积物中铅含量的快速荧光测定方法的研究   总被引:1,自引:0,他引:1  
建立了简单、快速测定Pb^2+的荧光测定方法。在pH<6.8的酸度条件下,Pb^2+与浓度为1.4-2.0mol/L的Cl^-形成的铅氯配合物在262.5nm的紫外光激光下发射出485.0nm可用于痕量铅离子测定的荧光,在选定激发单色器通带10.0nm,发射单色器通带20.0nm的仪器条件下,荧光强度与1.0×10^-7-1.0×10^-5mol/L范围的Pb^2+的线性关系可用△F=1.01×1  相似文献   

7.
膨润土对Pb2+的吸附性能及影响吸附的主要因素   总被引:30,自引:0,他引:30  
探讨了天然膨润土对Pb^2+的吸附性能及其主要影响因素,天然膨润土对Pb^2+的吸附能力很强,当Pb^2+的浓度小于20mg/L时,去除率可达99%以上,吸附受溶液PH、吸附剂用量以及振荡时间的影响,但溶液中存在的有机污染物不影响膨润土对Pb^2+的吸附。  相似文献   

8.
铜和锌离子对真鲷幼鱼组织酶活性的影响   总被引:22,自引:1,他引:21  
研究水中Cu^2+、Zn^2+对真鲷幼鱼组织CAT、GPT、胃蛋白酶活性的影响。结果表明:真鲷幼鱼暴露于不同浓度Cu^2+(0.5、0.75、1.5mg/L)、Zn^2+(1、2、4mg/L)海水中4d后,Cu^2+、Zn^2+对鳃,肝脏CAT,胃蛋白酶有抑制作用。  相似文献   

9.
基于Pb^2+与S^2-形成难溶的Pbs,过量的Pb^2+用四(4-甲基-3-磺酸苯基)卟啉[T(4-Mp)Ps4]光度法测定的原理,采用[Pb-T(4-Mp)Ps4]光度法间接测定空气中的硫化物。讨论了酸度对Pbs形成的影响;H2S吸收液的选择:共存离子的影响等。方法的线性范围为0 ̄0.32mg/L;最低检出浓度为0.02mg/L;精密度试验的变异系数为4.0%;回收率为96.0% ̄107.6%  相似文献   

10.
固定化产黄青霉废苗体吸附铅与脱附平衡   总被引:13,自引:0,他引:13  
徐容  王建华 《环境科学》1998,19(4):72-75
研究固定化产黄青霉废菌体对Pb^2+的吸附与脱附平衡的结果表明,Pb^2+的生物吸附受PH值的影响很大,温度的影响则很小,EDTA是洗脱固定化产黄青霉废菌体上所吸附Pb^2+的最佳脱附剂,在保持脱附率为100%的条件下〉EDTA的初2,固定化废菌颗粒的吸附量与最大固液比之间存在的正相关关系,0.1mol/L的EDTA在脱附Pb^2+时终浓度最高可达20700mg/L,最大固液比可达200以上,浓缩  相似文献   

11.
短期暴露实验中铜在鱼鳃表面的结合状态   总被引:1,自引:0,他引:1  
利用逐级提取的方法研究了短期暴露实验过程中鱼鳃表面不同结合状态的铜随时间变化的过程.考虑到实验过程中水环境条件的动态变化,对实验数据进行了校正.结果表明,鱼鳃对铜的吸收在3h左右达到稳态平衡,水提铜、鱼鳃表面易交换铜以及鱼鳃表面难交换铜随时间变化趋势一致。  相似文献   

12.
Boehmeria nivea(L.) Gaud. is a potential candidate for the remediation of Cd contaminated sites. The present investigation aims to explore Cd tolerance threshold and to quickly identify the role of exogenous organic acids in Cd uptake and abiotic metal stress damage.Elevated Cd levels(0–10 mg/L) resulted in an obvious rise in Cd accumulation, ranging from268.0 to 374.4 in root and 25.2 to 41.2 mg/kg dry weight in shoot, respectively. Citric acid at1.5 mmol/L significantly facilitated Cd uptake by 26.7% in root and by 1-fold in shoot,respectively. Cd translocation efficiency from root to shoot was improved by a maximum of66.4% under 3 mmol/L of oxalic acid. Citric acid exhibited more prominent mitigating effect than oxalic acid due to its stronger ligand affinity for chelating with metal and avoiding the toxicity injury of free Cd ions more efficiently. The present work provides a potential strategy for efficient Cd remediation with B. nivea.  相似文献   

13.
研究了水网藻在天然水体水样中的生长及对氮磷(N,P)的去除能力,结果表明水网藻在富营养化水及重营养化的湖水水样中均生长良好;富营养化水库及重营养化湖水经水网藻处理2d,4d、6d后,对氨氮,总氮,总磷去除率均在70%以上。  相似文献   

14.
研究了水网藻在天然水体水样中的生长及对氮磷(N,P)的去除能力,结果表明水网藻在富营养化水库水及重营养化的湖水水样中均生长良好;富营养化水库水(含TN 3.34—5.15mg/L、TP 0.10—0.19mg/L)及重营养化湖水(含TN33.86mg/L、TP 1.939mg/L)经水网藻(1g/L)处理2d、4d、6d后,对氨氮(NH4N)、总氮、总磷去除率均在70%以上.  相似文献   

15.
Increasing application of nanotechnology highlights the need to clarify and understand nanotoxicity. Mammalian and in vitro studies have raised concerns about the toxicity of titanium dioxide nanoparticles (TiO2-NPs), but there are limited data on ecotoxicity to aquatic organisms. In this work, the sub-acute toxicity of TiO2-NPs to carp (Cyprinus carpio) was assessed. Superoxide dismutase (SOD), catalase (CAT) and peroxidase (POD) activities and lipid peroxidation (LPO) levels in liver, gill and brain tissues of carps varied with concentration of TiO2-NPs suspensions and exposure time (up to 8 d). As a result, 100 and 200 mg/L TiO2-NPs caused statistically significant decrease in SOD, CAT and POD activities and significant increase in LPO levels in tissues (P < 0.05), suggesting that the fish exposed to these two concentrations of TiO2-NPs suffered from the oxidative stress. The extent of depletion of antioxidant enzymes activities and the elevation of LPO in the liver was the greatest, indicating that the liver might be the most susceptible organ to TiO2-NPs exposure. In addition, carps had gill pathologies including edema and thickening of gill lamellae as well as gill filaments, and liver pathologies including necrotic and apoptosis hepatocytes after exposed to 100 and 200 mg/L TiO2-NPs for 20 d. These results indicated a potential risk from TiO2-NPs released into the aqueous environment.  相似文献   

16.
A series of precious metals catalysts (M/TiO/, M = Ru, Rh, Pd, Ag, Ir, Pt or Au) were prepared by a light deposition method and the synergistic photocatalytic degradations of pyridine (20 mg/L) under UV irradiation (365 nm) using M/TiO2 with electron capture agent KBrO3 have been investigated. The results show that KBrO3 has a greatly synergistic role on M/TiO2 and the photocatalytic activity of M/TiO2 is closely related to its work function. Ag could greatly enhance the activity of TiO2 due to the binding characteristics of pyridine on Ag. Under the conditions of 0.5 wt.% Ag loading, Ag/TiO2 concentration of 0.1 g/L, KlrO3 concentration of 10 mmol/L and reaction liquid pH value at 9, the pyridine can be degraded by 64% within 3 hr, doubled than TiO2 photocatalytic system. The degradation kinetics of pyridine follows first-order kinetics and k = 5.53 × 10-3 min^-1.  相似文献   

17.
S-808是我国选矿科技工作者研制的一种新型磷矿浮选剂。湖北省荆襄磷矿矿务局王集矿,在选矿过程中采用S-808作为抑制剂直接浮选中低品位钙质磷块岩,获得特殊的选矿效果。为此化工部矿山局委托我们开展磷矿浮选剂S-808对鱼类的毒性和毒理学的研究。  相似文献   

18.
利用批量试验研究了不同浓度的亚硝酸盐对聚磷菌好氧摄磷过程的影响,以及在含盐废水硝化过程中亚硝酸盐的累积对聚磷菌好氧摄磷的影响.试验结果表明:亚硝态氮浓度为4 mg/L时,对聚磷菌摄磷有抑制作用,其对摄磷速率的抑制系数为0.08;亚硝态氮浓度为15 mg/L时,对聚磷菌摄磷产生明显的抑制,抑制系数增加到0.61.亚硝酸盐对聚磷菌的抑制作用主要与亚硝酸有关.本研究中亚硝酸浓度在0.000 2 mg/L以上时即对聚磷菌产生较强的抑制作用.亚硝酸盐对聚磷菌的抑制作用只是在亚硝酸盐存在的条件下才发生,一旦亚硝酸盐消失,对聚磷菌的抑制作用即可解除.含盐废水硝化过程中,在好氧反应开始1~2 h内,由于亚硝态氮浓度低,其对聚磷菌摄磷抑制作用小.随着亚硝态氮的逐步累积,亚硝态氮浓度达到8~9mg/L以上时,其对聚磷菌摄磷的抑制作用逐渐增强.进水氨氮浓度高时,好氧反应过程中pH值较低,会导致亚硝酸浓度增高,致使磷酸根的吸收量减少.  相似文献   

19.
选取中国南方地区典型生物尼罗罗非鱼作为受试生物,将其置于氯咪巴唑含量为2.00ng/mL的水体中暴露7d,考察氯咪巴唑在罗非鱼体内不同部位(鳃、肝脏、胆汁和血浆)的吸收和清除动力学过程,比较了氯咪巴唑在鱼体内不同部位的吸收和清除动力学速率.罗非鱼暴露于氯咪巴唑水溶液3d后,鱼体鳃、肝脏、胆汁和血浆中的氯咪巴唑达到最高浓度,分别为2.91ng/g,33.7ng/g,4.84ng/mL和2.58ng/mL;结束暴露3d后,氯咪巴唑在鳃、胆汁和血浆中的稳定浓度低于方法检测限,在肝脏中的稳定浓度为1.28ng/g.鱼体鳃、肝脏、胆汁和血浆中氯咪巴唑的吸收动力学常数ku分别为0.069,0.813,0.286和0.136h-1;清除动力学常数ke分别为0.033,0.029,0.082和0.060h-1;半衰期t1/2分别为21.1,23.9,8.51和11.6h.氯咪巴唑在罗非鱼体内的吸收/清除动力学过程均符合伪一级动力学方程,方程的相关系数r2范围为0.75~0.98.氯咪巴唑在鱼体鳃、肝脏、胆汁和血浆中的稳态生物富集系数对数值logBCFss分别为0.50,1.56,0.72和0.45,低于氯咪巴唑在野生罗非鱼体内的富集系数.  相似文献   

20.
A 52-day continuous semi-static waterborne exposure (test media renewed daily) regimen was employed to investigate the accumulation and elimination profiles of two iron oxide nanomaterials (nano-Fe2O3 and nano-Fe3O4) in zebrafish (Danio rerio). Adult zebrafish were exposed to nanomaterial suspensions with initial concentrations of 4.0 and 10.0 mg/L for 28 days and then were moved to clean water for 24 days to perform the elimination experiment. Fe content was measured in fish body and feces to provide data on accumulation and elimination of the two iron oxide nanomaterials in zebrafish. The experiment revealed that: (1) high accumulation of nano-Fe2O3 and nano-Fe3O4 were found in zebrafish, with maximum Fe contents, respectively, of 1.32 and 1.25 mg/g for 4.0 mg/L treatment groups and 1.15 and 0.90 mg/g for 10.0 mg/L treatment groups; (2) accumulated nanoparticles in zebrafish can be eliminated efficiently (the decrease of body burden of Fe conforms to a first-order decay equation) when fish were moved to nanoparticle-free water, and the elimination rates ranged from 86% to 100% by 24 days post-exposure; and (3) according to analysis of Fe content in fish excrement in the elimination phase, iron oxide nanomaterials may be adsorbed via the gastrointestinal tract, and stored for more than 12 days.  相似文献   

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