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1.
乳胶制品中N-亚硝胺析出物的GC-MS/SIM检测   总被引:4,自引:0,他引:4  
使用气相色谱-质谱(GC-MS/SIM)检测了乳胶制品中5种N-亚硝胺析出物,样品经过二氯甲烷萃取,用Rtx-5MS石英毛细管柱分离,采用内标法进行检测计算.实验得出5种N-亚硝基化合物的内标标准曲线日内RSD(小于5%),日间RSD(小于14%).N-亚硝基二乙胺(NDEA)、N-亚硝基二丙胺(NDPA)、N-亚硝基哌啶(NPIP)、N-亚硝基二丁胺(NDBA)、N-亚硝基二苯胺(NDPhA)的方法的检出限分别为2.0,5.0,10.0,1.0,112.0μg/L.运用该法对北京市场的乳胶制品进行了检测.  相似文献   

2.
建立了同时测定化妆品中10种挥发性亚硝胺(N-亚硝基二甲基胺,N-亚硝基二乙基胺、N-亚硝基二正丙基胺、N-亚硝基吗啉、N-亚硝基毗咯烷、N-亚硝基哌啶,N-亚硝基二正丁基胺、N-亚硝基二苯基胺、N-亚硝基二环己基胺及N-亚硝基二苄基胺)的气相色谱-串联质谱分析方法.膏霜、水剂、散粉、香波、唇膏等不同类型的化妆品样品分...  相似文献   

3.
GC-LRMS法测定啤酒中3种N-亚硝胺化合物   总被引:1,自引:0,他引:1  
用气相色谱-低分辨率质谱(GC-LRMS)联用法测定了啤酒中的3种亚硝胺.通过与脱亚硝基化试剂(HBr+HAc)作用,脱去亚硝基生成相应的二级胺,再与对甲苯磺酰氯反应,然后进行GC-LRMS分析.与原N-亚硝胺化合物相比,有效地改善了N-亚硝胺的色谱行为,衍生化后目标化合物的检测限降低了1~2个数量级(低至0.05μg...  相似文献   

4.
以林县食物中常见的串珠镰刀菌接种于小米和面粉,培养数日后加少量亚硝酸钠,可得一种新的亚硝基化合物:N-2-甲基丙基-N-1-甲基丙酮基亚硝胺(N-2-me-thylpropyl-N-1-methylacetonylnitrosamine,简称MAMPNA).这种化合物已用GC/MS鉴定,并经合成的MAMPNA证实.本文报道 MAMPNA的分离和鉴定,并对霉菌在亚硝胺生成中的作用及这种新亚硝基化合物生物合成的可能途径进行了讨论。  相似文献   

5.
丹酰氯柱前衍生高效液相色谱测定痕量脂肪族仲胺   总被引:2,自引:1,他引:1  
王志  徐宏达  傅承光 《色谱》1990,8(5):325-327
脂肪族仲胺在适宜条件下很容易形成强致癌物N-亚硝基化合物,因此研究N-亚硝基化合物及其前身物脂肪族仲胺的灵敏和准确的测定方法是研究癌变过程及其机理的前提条件。 丹酰氯作为荧光衍生试剂已广泛应用于氨基酸、生物胺和多胺的高效液相色谱分析,但应用于测定脂肪族仲胺尚未见报  相似文献   

6.
用从头计算Hartree-Fork方法和密度泛函B3LYP方法在6-311G(d)水平上对β-甲基亚硝基哌嗪类化合物代谢活化后的邻基参与作用机理进行了研究. 计算结果表明, 哌嗪环上N'原子和N'-取代基上氧原子的邻基参与作用明显提高了β-甲基亚硝基哌嗪代谢物的亲电反应活性, 促进了对DNA的烷化作用. 解释了甲基取代的N-亚硝基哌嗪较其母体化合物的致癌性具有显著增强的现象, 为N-亚硝基哌嗪在其γ-位形成第二亲电活性中心的致癌代谢途径提供了理论依据.  相似文献   

7.
利用滴定量热技术并结合适当的热力学循环测定了乙腈溶液中7个取代的N-亚硝基吲哚化合物中N—NO键的异裂能和均裂能, 能量范围分别为206.1~246.2 kJ/mol和119.1~124.6 kJ/mol. 表明N-亚硝基吲哚均裂释放NO自由基(NO·)比异裂释放NO正离子(NO+)要容易得多, 通过热力学循环得到的相应自由基负离子中N—NO键的异裂能和均裂能的能量范围分别为25.5~34.4和5.0~40.5 kJ/mol, 表明所研究化合物的自由基负离子在室温下很不稳定.  相似文献   

8.
亚硝胺的形成和性质 N-亚硝基化合物通常分为两大类——亚硝胺类和亚硝酰胺类。亚硝胺类化合物(以下简称亚硝胺,NA's),是指二烷基亚硝胺〔如二甲基亚硝胺,(CH_3)_2N-NO,DMNA〕、烷基芳基亚硝胺〔如甲基苯基亚硝胺,二芳基亚硝胺(如二苯基亚硝胺(C_6H_5)_2N—NO〕和环仲胺类的亚硝基化合物〔如亚硝基毗咯烷,,和亚硝基哌啶,等。亚硝酰胺是指含有或通式的化合物,如N-甲基-N-亚硝基脲CO  相似文献   

9.
建立了固相微萃取/气相色谱-质谱联用法(SPME/GC-MS)测定橡胶密封材料中N-亚硝基-N-甲基苯胺(NMPh A)、N-亚硝基-N-乙基苯胺(NEPh A)和N-亚硝基二苯基胺(NDPhe A)3种N-亚硝胺化合物含量的方法。样品参考国标GB/T 24153-2009进行预处理后,采用固相微萃取进行提取,对影响固相微萃取效率的纤维涂覆种类、萃取时间、搅拌速度和萃取温度等条件进行优化。在优化条件下,方法的线性范围为5~500μg/L,相关系数(r)均大于0.99,检出限为0.5μg/kg,回收率为77%~92%,相对标准偏差(RSD,n=6)为3.8%~7.7%。  相似文献   

10.
用质谱化学电离和量子化学方法研究了致癌物质N-亚硝基二甲胺(NDMA)的结构及性质,优化了化学电离质谱中主要离子的构型;探讨了NDMA的质子化合物的形成途径,经NDMA及其质子化合物的静电势计算,阐述了NDMA的可能致癌机理。  相似文献   

11.
The accelerated growth of aquaculture has resulted in a series of harmful effects to human health. The widespread and unrestricted use of antibiotics in this industry, to prevent bacterial infections, leads to remaining amounts in the aquatic environment. This has resulted in the emergence of antibiotic-resistant bacteria in aquaculture environments, in the increase in antibiotic resistance in fish pathogens as well as in the transfer of these resistance determinants to human pathogens. Moreover, the use of large amounts of antibiotics may lead to the presence of residual antibiotics in fish tissue and fish products. Fluoroquinolones, tetracyclines, penicillins, sulphonamides and other antibiotics, exhibiting activity against both Gram-positive and Gram-negative bacteria, are widely used for the treatment and prevention of diseases in fish. An extended and comprehensive review on the recent analytical methodologies concerning antibiotic residues in fish reported in the literature is provided in the present article. Emphasis is given on sample preparation regarding isolation and purification, chromatographic conditions and method validation according to legislation. Results of published assays are comparatively presented and criticised.  相似文献   

12.
采集了贵族个煤烘玉米为主要介质和河北2个饮水为介质氟病区内骨畸形病人的全血、尿、检测了其中8种元素含量,结果表明,贵州各氟病区少儿骨软化与成年骨硬化畸形病人的全血铝、钙、磷、铁和尿氟、铝均显著高于同龄对照组,尿磷均低于同龄对照组。少儿骨软化病人全血锌均下降,尿锌多下降。某水型氟病区骨软化经产妇尿氟、全血铜升高;骨软化少年全血铝显著升高,锌、铁下降,尿氟升高,尿锌,磷下降。海边的典型氟骨症病人全血、  相似文献   

13.
油页岩中微量元素赋存形态的研究   总被引:1,自引:0,他引:1  
通过浮沉实验及脱灰实验对抚顺、龙口、茂名3种油页岩样中部分微量元素进行了赋存形态的研究。结果表明,浮沉实验所得微量元素的赋存状态结果与脱灰实验基本一致,抚顺、龙口、茂名3种油页岩中大部分微量元素以无机态赋存,但也有所区别,抚顺、龙口、茂名油页岩中的元素V、Mn、Zn、Sr、Mo、Ta以及抚顺油页岩中的Cr、Te,龙口油页岩中的Cd、Sn,茂名油页岩中的Cd、Sn、Pb,主要赋存于无机矿物中;茂名油页岩中的Cr、Te,抚顺油页岩中的Cd,龙口油页岩中的Pb有相对较多的比例富集于有机质部分;龙口、茂名油页岩中的元素Co,抚顺油页岩中的Co、Sn、Pb,更多地富集于黏土矿中,但也有少部分富集于有机质中。  相似文献   

14.
利用火焰原子吸收法测定了中国银行韶关节市分行458名职工头发中Cu,Fe,Zn,Ca含量,运用统计学方法求出该人群中正常者与白发,脱发者Cu,Fe,ZnCa的特征含量,通过数据比较可看出,白发者Cu,Fe,Zn,Ca的含量均低于正常组,而脱发者与正常组较接近,经相关性检验,证明了Cu,Fe,Zn,Ca偏低的血发存在的相关性,与脱发没有相关性,经过性别比对,女性发中Cu,Fe,Zn,Ca含量均高于男  相似文献   

15.
Humans are exposed via air, water and food to a number of different arsenic compounds, the physical, chemical, and toxicological properties of which may vary considerably. In people eating much fish and shellfish the intake of organic arsenic compounds, mainly arsenobetaine, may exceed 1000 μg As per day, while the average daily intake of inorganic arsenic is in the order of 10–20 μg in most countries. Arsenobetaine, and most other arsenic compounds in food of marine origin, e.g. arsenocholine, trimethylarsine oxide and methylarsenic acids, are rapidly excreted in the urine and there seem to be only minor differences in metabolism between animal species. Trivalent inorganic arsenic (AsIII) is the main form of arsenic interacting with tissue constituents, due to its strong affinity for sulfhydryl groups. However, a substantial part of the absorbed AsIII is methylated in the body to less reactive metabolities, methylarsonic acid (MMA) and dimethylarsinic acid (DMA), which are rapidly excreted in the urine. All the different steps in the arsenic biotransformation in mammals have not yet been elucidated, but it seems likely that the methylation takes place mainly in the liver by transfer of methyl groups from S-adenosylmethionine to arsenic in its trivalent oxidation state. A substantial part of absorbed arsenate (AsV) is reduced to AsIII before being methylated in the liver. There are marked species differences in the methylation of inorganic arsenic. In most animal species DMA is the main metabolite. Compared with human subjects, very little MMA is produced. The marmoset monkey is the only species which has been shown unable to methylate inorganic arsenic. In contrast to other species, the rat shows a marked binding of DMA to the hemoglobin, which results in a low rate of urinary excretion of arsenic.  相似文献   

16.
The tributyltin species, the active ingredient in some antifouling paint formulations, is perhaps the most acutely toxic chemical to aquatic organisms ever deliberately introduced to water. It has been demonstrated to have an adverse effect on shellfish in France and England, and as a consequence the use of tributyltin-containing antifouling paints has been restricted in these countries. Other countries have banned the use of tributyltin-containing antifouling paints or are contemplating restrictions. This article reviews such environmental aspects of tributyltin as methods of analysis, toxicity, environmental occurrence, persistence and fate. Tributyltin concentrations in many locations may be high enough to cause chronic toxicity or harmful effects in some aquatic organisms, and in some locations the tributyltin concentrations may be high enough to be acutely toxic to some organisms. Biological degradation of tributyltin in water and sediment appears to be the most important factor limiting the persistence of tributyltin in aquatic environments. To some degree, then, the persistence of tributyltin in aquatic environments depends upon the nature of the ecosystem. Tributyltin exhibits low-to-medium persistence in water and moderate persistence in sediment. A summary is given of the regulatory status of tributyltin in some countries, and recommendations are made for further research.  相似文献   

17.
林长缨  丁晓静 《色谱》2020,38(9):999-1012
自1989年出现商品化的仪器以来,毛细管电泳(CE)技术在多个应用领域都取得了长足的进步与发展,重复性和准确性方面也有很大提升。能力验证样品分析的满意结果也显示了CE具备法规要求的准确定量能力。在疾病预防控制领域(简称"疾控")CE也展现出很多独具特色的应用,成为不可或缺的技术之一。在聚合酶链式反应产物分析、核酸序列测定、DNA变异和分型分析、食源性致病微生物分析及疫苗分析等工作中CE发挥了重要作用。应对突发疫情或公共卫生事件如食物中毒时,除了通过非靶标分析尽快锁定目标物外,还需要对大量样品做出快速而准确的分析,高通量和高灵敏的CE就十分适合解决这一问题。在公共卫生理化检验以确保食品、保健食品、特殊医学用途食品、化妆品和消毒产品等的安全中,CE也发挥了不可或缺的作用。作为一种使用较少危险化学品的环境友好方法,在需要按照标准或规范进行的疾控实验室常规检测中,CE仍受制于标准方法的缺失,未能发挥其应有的作用。但简单、快速、经济、耐用、高效的CE分离一旦与高灵敏通用检测器联用,必将更加从容地应对疾控领域中的各种挑战,发挥更大的作用。本文综述了2010~2019年CE在疾控领域的应用,分析了CE在疾控领域发展的机遇和挑战,对CE在疾控领域的发展前景进行了展望。  相似文献   

18.
《中国化学快报》2020,31(6):1462-1473
Graphene is a two-dimensional nanomaterial with huge surface area,high carrier mobility and high mechanical strength.Because of its great potential in nanotechnology and environmental protection,it has attracted much attention in environmental and energy fields since its discovery in 2004.Although graphene is a star material,many reviews have introduced its use in terms of energy,the research progress in the field of environment,especially water pollution control,has been rarely reported.Here,we review exhaustively the research progress of graphene-based materials in environmental pollution remediation in the past ten years.Firstly,the advantages and classification of graphene were introduced.Secondly,the research progress and main achievements of graphene and its composites in the fields of photocatalytic degradation,pollutant adsorption and water treatment were emphatically described,and the mechanism of action in the above fields was summarized.Finally,we discuss the problems existing in the preparation and summarize the application of graphene in the environment.  相似文献   

19.
Abstract

The ICP/MS method with lutetium, bismuth and indium as internal standards was used for the determination of thallium and other elements, i.e. Ti, V, Cr, Ni, Cu, Zn, Rb, Mo, Cd, As and Pb, in soils and rapeseeds. Samples were collected in two thallium highly pedogeochemicaily contaminated areas situated in South Bohemia and in Czech-Moravian Highlands, in two river alluvia, in two control sites with low levels of TI and in one spot with anthropogenic contamination. Levels higher than 2.5 mg kg?1 have been found in rapeseeds in the highly polluted areas (c. 2.8 mg kg?1 in soils). High correlation coefficients, r > 0.81, between content of TI in top- and sub-soils and rapeseeds were obtained. Thallium concentrations exceed twice of Pb content and by one order of magnitude of Cd amounts. This finding are very important because of the high toxicity of TI and the absence of threshold limits for TI in soils, agricultural products and foodstuffs in the Czech Republic.  相似文献   

20.
Many studies support the idea that alcohols in water undergo microphase transitions which are, in many respects, similar to micellization. To investigate the interactions in these systems even further, the volumes of transfer of normal alcohols of intermediate chain length, kept near infinite dilution, were measured from water to aqueous solutions of 2-propanol and 2-butoxyethanol. These results were compared with the volumes of transfer of the same alcohols to aqueous solutions of octyldimethylamine oxide, a well-characterized non-ionic surfactant. The trends observed are all very similar, exhibiting in many cases a maximum in the transition region. This tends to confirm the formation of mixed aggregates in aqueous mixtures of alcohols, but, in a general way, it is also shown that the magnitude of an extremum in the functions of transfer is related to the relative hydrophobicities of the present solutes, the extremum appearing in most cases only when the transferred solute is more hydrophobic than the main solute.  相似文献   

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