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1.
刘杰  WangJoseph 《环境化学》2001,20(4):398-404
根据二乙基二硫代氨基甲酸盐,硫脲或苯甲酸等环境污染质对蘑菇富含的酷氨酸酶所产生的抑制作用,研制了将蘑菇固定在碳糊而成的植物组织电极,用来有效地监测上述酷氨酸酶抑制剂,当存在酶的底和儿茶酚时,在该蘑菇组织电极上通过批量加入以及流动注射两种实验方式进行电流分析测定,结果表明这种生物传感器价廉,灵敏,快速,操作简易(无须温育)等,可用于现场环境监没,另外,还对电极制作条件诸如蘑菇用量及蘑菇切片部位等因素对电极行为的影响进行了研究。  相似文献   

2.
邻苯二酚对环境和人体具有危害作用,本实验用静电纺丝法制备了银掺杂氧化锌复合材料(Ag-ZnO),通过负载酪氨酸酶(Tyr)制备酪氨酸酶/银掺杂氧化锌/壳聚糖/玻碳生物电极(Tyr/Ag-ZnO/CS/GCE).利用扫描电子显微镜、X射线能谱分析、X射线粉末衍射和N2吸附脱附法对材料形貌、元素组成及比表面积进行表征.利用循环伏安法(CV)和交流阻抗法(EIS)对Tyr/Ag-ZnO/CS/GCE电极的电化学性能进行测试,利用计时电流法(IT)研究该电极对邻苯二酚(CA)的检测能力.结果表明,加入少量Ag可明显减小ZnO的颗粒尺寸,提高了复合材料导电性,Tyr/Ag-ZnO/CS/GCE对邻苯二酚的线性检测范围为1.00—47.00μmol·L-1,灵敏度56.35μA·(mmol·L-1)-1,检测限0.91μmol·L-1(S/N=3),且电极具有良好的重复性和抗干扰性.  相似文献   

3.
碳纤维电极上降解有机染料的研究   总被引:1,自引:0,他引:1  
以碳纤维电极为工作电极,CoSO4为催化剂,利用电生羟基自由基对中性红、罗丹明B、碱性品红等三种有机染料进行降解.研究电解电位、pH值、温度等因素对染料降解脱色的影响.在优化条件下,脱色率大于95%,COD去除率达90%以上.  相似文献   

4.
硝基苯类化合物在铜电极上的电还原特性和还原机理   总被引:5,自引:0,他引:5  
采用循环伏安法,对硝基苯类化合物在铜电极表面上的电还原特性进行了研究,评价了它们在铜电极上的电还原反应活性,分析了此类化合物在铜电极上的还原机理,并且讨论了电还原反应活性和此类化合物结构之间的关系.结果表明,硝基苯类化合物在铜电极表面有还原电位,也就是说,能在铜电极表面被直接还原.  相似文献   

5.
氯代烃在铜电极上的电还原特性和pH值的影响   总被引:1,自引:0,他引:1  
采用循环伏安法,对氯代烃类化合物在铜电极表面上的电还原特性进行了研究,结果表明,氯代烷烃类化合物能在铜电极表面被直接还原,氯代芳烃不易在铜电极上被直接还原.碱性条件有利于中间体碳负离子的形成;在酸性条件下,碳负离子与氢离子之间反应的几率增大,导致通过溶液的电流值增加.pH值对不同氯代烃在铜电极上的电还原特性有不同程度的影响,这主要取决于碳链(或苯环)上其它取代基的性质、结构、数量和它与氯在苯环上的相对位置.  相似文献   

6.
添加蘑菇渣对落叶堆肥过程中有机物的影响   总被引:2,自引:0,他引:2  
以落叶、蘑菇渣和鸡粪为原料进行好氧堆肥试验,研究蘑菇渣对落叶堆肥过程中有机物的影响.结果表明:添加蘑菇渣可以促进堆肥有机质、木质素、纤维素的分解,堆肥结束时,纤维素分解率分别为53.90%和47.29%,对半纤维素和羧基的影响不大,可以有效地提高堆肥终产品中腐殖质、游离腐植酸、总酸性基和酚羟基的含量.堆肥结束时,添加蘑菇渣和未添加蘑菇渣处理的腐殖质含量分别为260.79 g·kg-1和215.01 g·kg-1,游离腐植酸含量分别为222.23 g·kg-1和189.75 g·kg-1.红外光谱表明,添加蘑菇渣可以有效地促进碳水化合物、蛋白质、脂肪族化合物和木质素等的分解,加快堆肥稳定腐熟.  相似文献   

7.
本文对甲醇催化膜电极继续进行了研究。在原有的铂-铑催化膜电极基础上,较系统地研究了铂钯(10—100%Pd)体系;铂铑(15—45%Rh)体系;以及铂-钯加贱金属体系。分别考查了催化膜电极的灵敏度、响应时间、干扰性能;并使用扫描电镜,X-射线光电子能谱,X-射线衍射等多种物理分析方法对催化膜电极表面状态进行了研究,验证了响应曲线的动力学过程,甲醇在电极上的氧化反应是属于一级动力学响应。据此筛选出较合适的甲醇催化膜电极。  相似文献   

8.
高温高压水热体系在科学实验、工业生产和自然界中广泛存在,pH是水溶液重要的物理化学参数之一,原位获得水热体系的pH具有重要意义.传统的玻璃电极由于自身的缺点,使用范围受到极大限制,已无法满足特殊领域的需求,许多研究者展开了有关玻璃电极替代品的研究.其中Ir/IrOxpH电极作为一种全固态金属/金属氧化物电极,具有力学性能好、容易制备并可以微型化的特点,且具有较好的响应性能,可用于高温高压环境等特点,引起了广泛的关注.本文介绍了Ir/IrOxpH电极对H+的响应原理,总结了Ir/IrOxpH电极的制备方法及响应性能,提出了Ir/IrOxpH电极存在的不足及改进方法,并对Ir/IrOxpH电极的发展进行了展望.  相似文献   

9.
四川凉山州9种野生蘑菇的重金属含量   总被引:6,自引:0,他引:6  
报道了采集于四川凉山州9种野生蘑菇及相关土壤的重金属Cd、Pb、Zn、Hg和As的含量.结果表明,供试土壤均未检出Hg,3个采集地除会理林家山土壤样品有Cd的检出,另外两个样地土壤未检出Cd.土壤中Pb、Zn和As在干土中的含量分别为52.806 4~274.731 0 mg/kg、18.747 5~164.585 8 mg/kg和3.970 9~10.749 9 mg/kg.野生蘑菇对Cd和Hg具有很强的积累能力,在土壤中没有Cd和Hg检出的情况下,蘑菇中均测出了Cd和Hg,Cd含量高达28.383 6 mg/kg出现在梭孢环柄菇(Lepita ventriosospora),Hg含量最高为0.860 7 mg/kg出现在大白菇(Russula deli-ca).在土壤受Pb污染的情况下,大白菇子实体积累Pb的能力最强,含量为115.929 0 mg/kg.本次蘑菇样品Zn的含量不高.蘑菇对As的积累与土壤中As含量高低有关,最高含量为喇叭陀螺菌(Gomphus floccosus),为4.003 5 mg/kg.表明蘑菇对重金属的积累具有种特异性,与环境土壤重金属含量有关.基于蘑菇对重金属的强积累能力,可考虑作为净化重金属污染环境的特种生物.图1表2参11  相似文献   

10.
采用三维电极电化学反应器组合Fenton试剂法对经过二级生化处理后的焦化废水进行深度处理。在三维电极参数一定的条件下,考察了影nfi]TOC去除率的影响因素,探讨了该反应体系的降解动力学及降解机理。正交试验结果表明,反应体系中各参数的最佳值分别为p(H202投加量)=300mg·L-1,pH3.4,反应时间为90min,c(FeS04-7H20投加量)为3.5mmol·L-1,TOC去除率可达到61.7%。焦化废水的降解反应表现为一级动力学。紫外吸收光谱分析结果,废水中有机物彻底发生了降解矿化,这为三维电极组合Fenton试剂工艺在焦化废水深度处理中的工程应用提供了一定的理论指导。  相似文献   

11.
螯合剂和表面活性剂辅助金福菇修复重金属污染土壤   总被引:1,自引:0,他引:1  
通过温室大棚盆栽试验,研究螯合剂和表面活性剂单独或复合处理辅助金福菇修复重金属污染土壤的效果.结果表明,单独添加EDTA(乙二胺四乙酸)时,高浓度的EDTA(E2,5 mmol kg-1)使金福菇的生物量比对照降低26%,子实体Pb、Cu和Cd的浓度分别比对照提高15~88倍、0.8~3.3倍和0.5~0.6倍.单独添加表面活性剂时,各处理生物量与对照没有显著差异,且重金属浓度变化幅度没有单独添加EDTA的处理大.低浓度的表面活性剂对金福菇吸收各种重金属的影响较小,而高浓度则影响较大,但与表面活性剂及重金属种类有关.共同添加EDTA和表面活性剂时,只有当EDTA和CTAB(溴化十六烷基三甲铵)共同添加时,EC2(EDTA:CTAB=1:1)和EC3(EDTA:CTAB=2:1)的生物量显著降低,其余处理与对照差异不明显.EC3的子实体Pb和Cu浓度达到所有处理中的最大值,分别为(1 533.61±131.34)、(1 786.11±328.33)mg kg-1.EDTA和SDS(十二烷基磺酸钠)浓度比为2:1(ES3)时,子实体Cd浓度达到最大值,为(50.56±11.55)mg kg-1.此外,还分析了不同处理的重金属总积累量和富集系数.结果显示,在螯合剂和表面活性剂辅助下,金福菇修复复合重金属污染土壤具有很大的潜能.  相似文献   

12.
不同时期添加蘑菇渣对落叶堆肥过程的影响   总被引:3,自引:0,他引:3  
研究不同时期添加蘑菇渣对落叶堆肥过程的影响.结果表明:堆肥降温期添加蘑菇渣有利于提高有机质的降解率,堆肥末期各处理有机质降解率分别为15.85%,10.17%,12.90%和15.16%;有利于吸收固定堆肥中的氨,减少氨的挥发,降低堆肥的pH值.在堆肥初始一次性添加蘑菇渣,有利于堆肥总氮的积累,提高堆肥产品中胡敏酸和腐殖质含量,降低堆肥总氮损失率.在堆肥初始和降温期分次添加蘑菇渣有利于堆肥硝态氮的合成,富里酸的分解以及HA/FA的增加.在整个堆肥过程中,各处理HA和HA/FA均呈增加趋势,FA呈降低趋势,较好地反映了落叶堆肥的腐熟程度.在堆肥不同阶段添加蘑菇渣各有其优点,综合后认为在堆肥初始添加蘑菇渣的效果最为理想.  相似文献   

13.
Indian bullfrog Haplobatrachus tigerinus (Daudin) was exposed to sublethal dose (1/3 of LC50 I.E. 1.166 mg/kg) of fenvalerate technical grade and the effect was studied on the specific activity of acetyl cholinesterase in the different tissues of frog viz., brain, muscle, liver, kidney and testis at different time periods viz., 3,6, 12, 24, 48 and 72 hours. The inhibition of specific activity of acetyl cholinesterase was in the order of kidney > brain > muscle > liver > testis. A significant inhibition was noticed in kidney at 12 hours (-64.33%) and no effect was noticed at 3 hours in testis (+0.67%). The AChE activity was inhibited in first three hours of administration of fenvalerate in all the tissue tested. The inhibition continued upto 6 hours or 2 hours in different tissue but the recovery was started by 24 hours and almost completed by 72 hours.  相似文献   

14.
A study was conducted to determine the effects of long-term exposure to carbofuran on erythrocyte and liver acetylcholinesterase (AChE) activity in Cyprinus carpio, and assess which tissue was more sensitive to pesticide exposure examining this enzyme. Fish were allowed to accilimatize in toxicant-free water for 24 days after 60-day exposure. AChE activity was determined with a spectrophotometer using acetylthiocholine iodide as a substrate in erythrocytes and liver. Enzymic activity of erythrocytes and liver decreased over time. A higher degree of enzyme inhibition was observed in erythrocyte compared to liver. The degree of enzyme inhibition was positively correlated with exposure time. When exposed fish were transferred to clean water, recovery was greater in erythrocytes than liver. Erythrocyte AChE activity recovered after 18 days, while it required 21 days in liver. The findings of this study indicate that erythrocyte AChE is more sensitive to carbofuran than liver. The greater sensitivity of erythrocyte AChE suggests that it may be more useful as a biomarker for monitoring status of pollution in freshwater bodies.  相似文献   

15.
Current Trends in Plant and Animal Population Monitoring   总被引:3,自引:0,他引:3  
Abstract:  Animal and plant population monitoring programs are critical for identifying species at risk, evaluating the effects of management or harvest, and tracking invasive and pest species. Nevertheless, monitoring activities are highly decentralized, which makes it difficult for researchers or conservation planners to get a good general picture of what real-world monitoring programs actually entail. We used a Web-based survey to collect information on population monitoring programs. The survey focused on basic questions about each program, including motivations for monitoring, types of data being collected, spatiotemporal design of the program, and reasons for choosing that design. We received responses from 311 people involved in monitoring of various species and used these responses to summarize ongoing monitoring efforts. We also used responses to determine whether monitoring strategies have changed over time and whether they differed among monitoring agencies. Most commonly, monitoring entailed collection of count data at multiple sites with the primary goal of detecting trends. But we also found that goals and strategies for monitoring appeared to be diversifying, that area-occupied and presence–absence approaches appeared to be gaining in popularity, and that several other promising approaches (monitoring to reduce parameter uncertainty, risk-based monitoring, and directly linking monitoring data to management decisions) have yet to become widely established. We suggest that improved communication between researchers studying monitoring designs and those who are charged with putting these designs into practice could further improve monitoring programs and better match sampling designs to the objectives of monitoring programs.  相似文献   

16.
We examined the impact of seven species of mobile mushroom corals (Fungiidae) on the community structure of sheltered reef slopes in terms of their patterns of migration, habitat use and competition with other benthic organisms. On fringing reefs at Eilat, Red Sea, polyps detached at 1 to 6 cm length, and grew to 11–55 cm length. Attached mushroom corals were oriented vertically in reef cavities. Detached corals migrated downward on the reef slope and onto rubble or soft substratum at the reef base, at 29 to 71 cmyr–1. Mobility decreased with corallum size and extent of undersurface ornamentation. In aquaria, small corals righted themselves and migrated up to 6 cm d–1 by nocturnally inflating and pushing their tissues against the substratum. Autonomous coral behavior and storm-generated water motion appeared to account for most fungiid mobility at Eilat. Mushroom corals did not damage each other upon contact, even in multi-species aggregations, but unilaterally damaged non-fungiid scleractinian corals. Their dominance during contact interactions retards overgrowth by larger attached scleractinians, and mobility allows them to colonize soft substrata not accessible to most other reef corals.  相似文献   

17.
Abstract:  Population monitoring is central to most demographic studies and conservation efforts, but it may not always be directed at the most appropriate life stage. We used stochastic simulation modeling to evaluate the effectiveness of a monitoring program for a well-studied population of Eastern Imperial Eagles ( Aquila heliaca ) in Kazakhstan. Specifically, we asked whether the most appropriate data were being collected to understand system state and population dynamics. Our models were parameterized with data collected over the course of 25 years of study of this population. We used the models to conduct simulation experiments to evaluate relationships between monitored or potentially monitored parameters and the demographic variables of interest—population size ( N ) and population growth (λ). Static analyses showed that traditional territory-based monitoring was a poor indicator of eagle population size and growth and that monitoring survivorship would provide more information about these parameters. Nevertheless, these same traditionally monitored territory-based parameters had greater power to detect long-term changes in population size than did survivorship or population structure. Regardless of the taxa considered, threats can have immediate impacts on population size and growth or longer-term impacts on population dynamics. Prudently designed monitoring programs for any species will detect the demographic effects of both types of threats.  相似文献   

18.
This study investigated the potential use of chelator-induced bioextraction of heavy metals from soil by Coprinus comatus in a pot experiment. Two production waves of the mushroom were obtained to determine biomass and metal concentration. The application of ethylenediaminetetraacetic acid (EDTA) or nitrilotriacetate (NTA) slightly inhibited the growth of C. comatus, but significantly enhanced the accumulation of heavy metals in fruiting bodies compared with the control. The highest concentrations of Pb, Cu and Cd reached 900.60, 783.61 and 23.64 mg·kg?1 in a single pot, respectively. However, application of citric acid (CA) had no effect on metal uptake. Moreover, chelators applied to soil after fructification increased the dry biomass and metal concentration in fruiting bodies compared with those applied before sowing mycelia. EDTA was more efficient for inducing metal uptake by C. comatus than NTA or CA, and split applications of EDTA after fructification resulted in the highest total metal uptake by mushroom, i.e. 19.08±2.84, 17.57±0.69 and 0.55±0.06 mg for Pb, Cu and Cd, respectively, which were 130, 12 and 5 times values obtained with the control. Interestingly, many mushrooms turned blue after soil had been treated with chelator, indicating that these mushrooms are rich in Cu.  相似文献   

19.
Bioaccumulation and biological effects of pollution were assessed in mussels (Mytilus galloprovincialis) caged for one month at three sites in the Oiartzun estuary (south-eastern Bay of Biscay, Spain) with the aim of evaluating their usefulness within the investigative monitoring defined in the European Union Water Framework Directive (WFD). The highest concentrations of organic contaminants determined in mussels' tissue were detected towards the inner part of the estuary but no gradient pattern was found for metal bioaccumulation. Population fitness responses measured as condition index, stress on stress and gonad index were similar in all caged mussels and did not follow the organic pollution gradient. However, biomarkers determined at tissue, cell and protein level (histopathology, micronuclei frequency, malondialdehyde levels and vitellogenin-like protein levels) revealed a higher stress syndrome at the inner part of the estuary showing signs of genotoxicity, oxidative stress and endocrine disruption. Overall, the integrated chemical–biological approach in connection with mussel caging technique proved to be a useful tool to assess environmental pollution, allowing a better understanding of the cause–effect relationship within the investigative monitoring defined in the WFD.  相似文献   

20.
Cell biosensors are currently emerging as novel, sensitive techniques to monitor the toxicity of environmental pollutants. Here, we have developed electric cell-substrate impedance sensing (ECIS) for on-line monitoring of the behavior of insect cells. Cells were cultured on a microarray of eight small gold electrodes, deposited on the bottom of tissue culture wells. Upon inoculation, cells showed a tendency to drift downward and attached to the gold surface precoated with the protein Concanavalin A to accelerate the cell attachment. The impedance increased because the cells acted as insulating particles to restrict the current flow. The resulting impedance, a coordination of many biological reactions within the cell, was continuously monitored in real-time to reveal information about cell spreading and micromotion. As the cell behavior was sensitive to external chemicals, the applicability of ECIS for inhibition assays was demonstrated with HgCl2, 2,4,6-trinitrotoluene (TNT), 2-amino 4,6-dinitrotoluene (2-ADNT) and 1,3,5-trinitrobenzene (TNB). Electronic Publication  相似文献   

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