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1.
镍和铬是生物体必需的微量元素,但是大量地摄入它们会对人体产生许多不良的影响。如镍有致敏性、致癌性、生物毒性、胚胎毒性和免疫毒性等[1];铬摄入过多可发生肝、肺、肾功能障碍,还可引起上呼吸道炎症和黏膜溃疡、肝肾毒性、遗传毒性、生殖毒性及致癌性[2]等。镍铬烤瓷牙事件使镍和铬的毒  相似文献   

2.
太湖地区全沉积物毒性识别评估研究   总被引:3,自引:0,他引:3  
本研究用淡水单孔蚓(Monopylephorus limosus)和铜锈环棱螺(Bellamya aeruginosa)作为受试生物,对太湖沉积物的毒性进行筛查,采用全沉积物毒性识别评估(TIE)技术描述和鉴定太湖沉积物的主要毒性来源(重金属、氨氮或非极性有机物).通过初始毒性实验筛选出4个对铜锈环棱螺具有毒性和1个对淡水单孔蚓具有毒性的沉积物样点.通过TIE,对于铜锈环棱螺,高风险点T6的毒性来源是非极性有机物和重金属;对于淡水单孔蚓,高风险点T12的毒性来源是非极性有机物、氨氮、重金属.T6和T12中4种多环芳烃(苯并[b+k]荧葸、苊、二氢苊、茚并[1,2,3.cd]芘)是非极性有机物中产生生物毒性的来源之一,而Pb是T6和T12中产生毒性的主要重金属.  相似文献   

3.
离子液体的毒性   总被引:13,自引:0,他引:13  
离子液体因其特有的物化性质受到越来越多的关注,并被认为是环境友好的"绿色产品"。但是有关离子液体的潜在毒性一直被人们所忽视,直到最近才有少量报道。本文综述了离子液体毒性研究的相关情况:详细介绍了离子液体毒性研究的各种方法及优缺点;离子液体对各类生物的急性毒性和慢性毒性;离子液体的各部分组成,尤其是阳离子核种类、取代烷基碳链长度和阴离子种类对离子液体毒性的影响情况,以及SAR理论在离子液体毒性研究中的应用情况。在此基础上提出今后离子液体毒性研究的发展方向。  相似文献   

4.
随着纳米技术和纳米材料在工业和生活中的大规模应用,大量的人工纳米颗粒物将不可避免地释放到环境介质(如水体、土壤、沉积物等)中。纳米颗粒物所具有的独特性质已引发人们对它们可能造成的健康风险和环境危害的关注和讨论。本文对目前环境中存在的几种主要典型人工纳米颗粒物的性质、来源、纳米毒性及影响纳米毒性的因素进行详细介绍,阐述了纳米颗粒物对生物的可能致毒机理。在分析纳米颗粒物毒性影响因素过程中,提出了纳米材料在环境中相关毒性研究展望。最后文中总结目前纳米材料在环境中的行为和毒性研究中所存在和面临的问题,并在此基础上提出将来纳米材料毒性的研究方向(如纳米材料的定量结构-活性关系,纳米材料表征技术及慢性毒性研究等)及需要改进的相关建议。  相似文献   

5.
水体总毒性在线检测仪器的研制   总被引:2,自引:0,他引:2  
研制了基于电化学媒介体法的水体总毒性在线检测仪器, 通过对比水样和标样中微生物的呼吸活性差异, 实现对水体总毒性的在线监测.毒性检测的受试体微生物为原位培养微生物.电化学检测采用三电极系统, 其中铂微阵列电极、Ag/AgCl(3 mol/L KCl)电极和金丝电极分别作为工作电极、参比电极和对电极.对浓度为5.0、10.0和20.0 mg/L的模型毒物3,5-二氯苯酚(DCP)进行检测, 获得的微生物呼吸活性抑制率分别为24.4%、48.9%和59.2%.在连续在线监测过程中, 仪器能够对所有随机加入毒性物质(5.0 mg/L DCP)的水样输出毒性警报(以10%的呼吸抑制率为毒性报警临界值), 表明此仪器可以用于水体总毒性在线检测和预警.  相似文献   

6.
浓度加和(CA)模型是评估与预测化学混合物毒性效应的常用模型之一,已广泛应用于药物组合与农药混配等多个混合物体系. 然而,CA不能用于包含不同时间具有不同效应组分的混合物体系,需要拓展. 以具有不同时间依赖毒性特征的三种三嗪类除草剂即嗪草酮(MET)、西草净(SIM)和环嗪酮(HEX)为混合物组分,以直接均分射线法(EquRay)构建它们的二元混合物,以青海弧菌Q67为受试生物,在6个不同时间(即0.25,2,4,8,12和16 h)下测定各混合物组分及其二元混合物暴露于Q67时的发光抑制毒性,分析与归纳抑制毒性随时间的变化规律. 结果表明,三种除草剂对发光菌Q67的发光抑制毒性具有不同的时间变化规律:MET的毒性随时间延长有明显增大的趋势,SIM的毒性在不同时间没有显著性变化,而HEX随着时间的延长毒性开始有所增加,而后变化很小;二元混合物毒性的时间变化规律与混合物组分有关,MET与HEX的二元混合物体系的毒性随暴露时间的延长而逐步增加,MET-SIM体系开始有所下降而后缓慢增加,而SIM-HEX体系的毒性在不同时间差异不明显;应用拓展后的CA模型分析所有二元混合物在不同时间点的毒性变化,表明都是加和的,没有协同或拮抗作用.  相似文献   

7.
随着商品中所含各种化合物的不断使用,人们日益关注其对人类及生态环境的安全危害。在过去的几年里,通过计算方法预测化合物毒性已经显示出极大的潜力。在此,总结了常用的机器学习和深度学习算法在建立毒性预测模型上的优缺点,并系统回顾了近三年发表的可免费访问的毒性预测网络服务器。此外,还讨论了基于人工智能和互联网时代下毒性预测所面临的机遇和挑战。希望指导人们合理的选择算法和网络服务器进行建模及化合物毒性评估。  相似文献   

8.
<正>乙二醇醚类作为优良的有机溶剂在涂料、油墨、皮革、染料、清洗和农药等行业广泛使用。2000年以来,我国乙二醇醚类的生产和使用量逐年增加,2012年达到50万t的生产使用规模,职业暴露人群将达到10万人。整体动物和体外毒理学研究表明,乙二醇醚类有血液毒性、生殖毒性、肝肾毒性、发育毒性和致畸毒性等[1],可能会引起职业人群精液质量的下降。至今,乙二醇醚类产生职业人群生殖毒性的结论尚缺乏职业暴露人群的研究资料的支持。  相似文献   

9.
敌敌畏及其代谢产物对青海弧菌和秀丽线虫的联合毒性   总被引:1,自引:0,他引:1  
郑乔峰  居珍  刘树深 《化学学报》2019,77(10):1008-1016
实际环境中农药与其代谢产物常常共存, 农药和代谢产物之间的联合毒性(协同或拮抗)直接影响农药的环境风险评估. 农药敌敌畏(A)在环境中主要有三种代谢产物(二氯乙醇(B)、二氯乙酸(C)、磷酸二甲酯(D)), 在不同环境条件下其浓度组成有多种变化, 与敌敌畏形成多种混合物. 本文应用优化实验设计方法从中优选5条具有不同浓度配比的混合物射线, 选择水生生物青海弧菌(Vibrio qinghaiensis sp.-Q67)和土壤生物秀丽线虫(Caenorhabditis elegans)为受试生物, 通过微板毒性分析方法测试母体A及其代谢产物B、C、D以及它们的混合物射线在不同暴露时间及不同浓度水平下对青海弧菌的发光抑制毒性和对秀丽线虫的致死毒性, 应用含95%观测置信区间的组合指数评估各混合物射线在不同暴露时间下联合毒性随混合物浓度水平的变化. 结果表明: 对青海弧菌, 母体A及2个代谢产物C和D对Q67的发光抑制毒性不随时间变化而变化, 但代谢产物B在12 h的毒性显著大于0.25 h, 且母体A无论在哪个暴露时间其毒性都大于代谢产物. 对秀丽线虫, A与B、C及D的致死毒性不随时间而变化. A、C及D的毒性基本相同, 且均显著大于B. 5条混合物射线在不同浓度水平下, 在12 h对青海弧菌的发光抑制毒性显著大于0.25 h. 无论在0.25 h或12 h, 混合物射线对青海弧菌的联合毒性均是低浓度加和与高浓度拮抗. 对于秀丽线虫, 5条射线的毒性均不随时间而变化. 在2个时间点的联合毒性除射线R2和R5具有轻微拮抗外, 其它都是浓度加和.  相似文献   

10.
碳纳米管的细胞毒性   总被引:4,自引:0,他引:4  
诸颖  李文新 《中国科学B辑》2008,38(8):677-684
随着碳纳米管(CNTs)的大量生产和应用,它们对环境和人类健康可能带来不利的影响.因此,CNTs的生物效应和安全性研究引起科学家和各国政府的高度重视.扼要介绍了CNTs的体外毒性研究的主要结果,重点讨论了影响CNTs细胞毒性的诸多因素,包括CNTs的种类、所含杂质、CNTs的长度、直径和长径比、CNTs水溶性修饰以及细胞存活率的测定方法.然而,迄今CNTs细胞毒性研究取得的实验结果缺少可比性,分歧也屡见不鲜.为了更准确地评估CNTs对人类健康的潜在风险,我们认为细胞毒性检测中应该充分注意CNTs的化学修饰以及CNTs的定量表征等问题,尤为重要的是要加强CNTs细胞毒性的物理化学机制研究,逐步形成具有纳米毒理学自身特点的毒性检测方法和评估标准.  相似文献   

11.
Fast atom bombardment mass spectra of a range of involatile monophosphonated and mixed sulphonated/monophosphonated azo dyestuffs are presented. Good spectra are obtained and the fragmentations are discussed with special reference to the ions formed by cleavage of the azo linkage. The negative ion spectra are shown to be superior in terms of signal to background and structural information to those obtained in the positive ion mode. The results are compared with those obtained from sulphonated azo dyestuffs.  相似文献   

12.
Fast atom bombardment mass spectra of a range of involatile mono and disazo sulphonated dyestuffs are presented. Excellent spectra are obtained for dyestuffs containing up to five sulphonate groups. The fragmentations are discussed with special reference to the ions formed by cleavage of the azo linkage. The negative ion spectra are shown to be superior to those obtained in the positive ion mode.  相似文献   

13.
From the azo dyestuff 2-aminophenyl acetic acid → β-naphthol two isomeric 1:2 chromium complexes could be prepared, which probably are coordinated in the sandwich arrangement. The dyestuff 2-aminophenyl acetic acid → phenyl-methyl-pyrazolone is forming only one 1:2 chromium complex, probably coordinated in the DREW -PFITZNER arrangement. These complexes are the first proved examples for metal-containing azo dyestuffs with ortho condensed 6- and 7-membered rings.  相似文献   

14.
Geary WJ  Bottomley F 《Talanta》1967,14(5):537-542
The heterocyclic azo dyestuffs 4-(n-methyl-2 -pyridylazo)-resorcinol (where n = 3', 4', 5', 6') have been prepared, and their possible use as spectrophotometric reagents investigated. The dyestuffs are shown to function analogously to the parent ligand 4-(2'-pyridylazo) resorcinol (PAR) in giving red complexes with the ions Co(2+), Ni(2+), Cu(2+), Zn(2+) and UO(2)(2+). Steric effects resulting from the position of the methyl group in the heterocyclic ring are shown to occur in relation both to the spectra of the dyestuffs themselves and to the sensitivity of their reactions with the metal ions.  相似文献   

15.
The complexing ability of derivatives of azobenzene (I) is well known (I) and responsible for the production of a wide variety of dyestuffs and analytical chemicals. While the azo group generally participates in the coordination, the determination of the degree of its interaction is complicated by other functional groups which are also coordinated with the transition metal. In a previous publication (2), we reported the preparation of the silver and palladium complexes of benzo[c]cinnoline (II) and proposed that these results might be used to explain the electron donor properties of azobenzene. We are now reporting the preparation of some additional complexes with ligands containing the azo group.  相似文献   

16.
The magnetic equivalence of ligand protons was examined with aid of NMR. spectroscopy for a large number of 1:2 CoIII-complexes of tridentated azo dyestuffs forming a representative cross section of the whole class of substances. It was established by this investigation that ligands with a moderately polarised azo group have a particular inclination to form asymmetrical complexes in which the protons of the two ligands are not magnetically equivalent. On the other hand, ligands having a non-polarised or a strongly polarised azo group tend to form symmetrical complexes. In three cases both symmetrical and asymmetrical complexes were isolated. As in previous investigations [1], up to a total of 5 complexes were again observed, which indicates at least two causes governing the symmetry conditions. The phenomena described here could be explained with an alternative coordination of the two azo nitrogen atoms. On the basis of the NMR. results, however, preference is given to an exchange of the azo with the hydrazone form.  相似文献   

17.
The complex forming properties of the thiazole azo dyestuffs and related compounds have been studied in order to try to ascertain the role of importance of the donor atoms present in thiazolylazo-resorcinol. Potentiometric titrations were employed for these determinations, although in many cases meaningful stability constants could not be obtained because of reagent instability or insolubility of the complexes formed on chelation.  相似文献   

18.
建立了染料痕量阴离子的微波消解离子色谱方法。对离子色谱的干扰,pH对分离效果影响,淋洗液的选择对保留时间的影响,流速对峰高、峰面积、分离度和理论谈板数的影响进行了研究。结果表明:六种阴离子具有良好的线性关系,相关系数为0.9991-0.9999,检出限为0.0002-0.0032mg/L,加标回收率为97.6%-101.4%,阴离子精密度<0.03%-2.55%,仪器定量和定性精密度<3.0%,本方法精密、准确、快速,对氮杂BODIPY荧光染料2,6-位置引入卤素的含量测定具有实际应用价值。  相似文献   

19.
5,11,17,23‐Tetra‐tert‐butyl‐25,26,27,28‐tetrahydroxycalix[4]arene and 25,26,27,28‐tetrahydroxycalix[4]arene were synthesized based on previous literature. Firstly, several azo dyes were synthesized, and then, these dyestuffs were chlorinated through reaction with thionyl chloride. Secondly, the azo compounds bonded with methylene chloride and reacted with 25,26,27,28‐tetrahydroxycalix[4]arene, and then, six novel disazocalix[4]arene derivatives 4 ( a – f ) were achieved. Their structures were characterized as Fourier transform infrared, 1H‐NMR, and elemental analysis. In this study, we investigated the solvatochromic properties of the compounds and the acid–base effect on their ultraviolet–visible absorption by using six solvents.  相似文献   

20.
The solid-state structures of 43 Li, Na, K, Rb, Mg, Ca and Ba salts of para- and meta-sulfonated azo dyes have been examined and can be categorised into three structural classes. All form alternating organic and inorganic layers, however, the nature of the coordination network that forms these layers differs from class to class. The class of structure formed was found to be primarily governed by metal type, but can also be influenced by the nature and position of the organic substituents. Thus, for the para-sulfonated azo dyes, Mg compounds form solvent-separated ion-pair solids; Ca, Ba and Li compounds form simple coordination networks based on metal-sulfonate bonding; and Na, K and Rb compounds form more complex, higher dimensional coordination networks. Compounds of meta-sulfonated azo dyes follow a similar pattern, but here, Ca species may also form solvent-separated ion-pair solids. Significantly, this first attempt to classify such dyestuffs using the principles of supramolecular chemistry succeeds not only for the simple dyes used here as model compounds, but also for more complex molecules, similar to modern colourants.  相似文献   

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