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1.
肺癌组织中微量元素的研究   总被引:1,自引:0,他引:1  
用ICP等离子体发射光谱法测定了肺癌组织中Cd、Cr、Co、Mg、Mn、Ni、Pb、Sr、Ti、Se、Al、Ba、Zn、Fe、Cu、Be等16种微量元素古量。结果显示.与同侧无癌肺叶组织相比较,肺鳞癌和肺腺癌组织中Cr、Cu和Mg含量均显著升高.Cd、Mn和Zn含量均显著降低。两型肺癌组织中Cd、Fe和Ba3种元素音量之间存在明显差异.而两型肺癌的同侧无癌肺叶组织的微量元素含量之间除Cd外均无明显差异。  相似文献   

2.
基于秦皇岛滨海湿地人工种植耐高盐碱蓬修复工程试验,通过分析湿地土壤沉积物及耐高盐碱蓬中不同金属元素的含量与变化,研究了耐高盐碱蓬对金属元素的富集特征。结果显示:湿地沉积物中Fe、Mn、Cr、Pb和Zn的浓度较高,分别为8 210. 94、110. 04、8. 78、8. 25、10. 95 mg/kg,Cd的浓度最低,平均值为0. 022 mg/kg,湿地试验区土壤中同一金属元素变异程度较小,分布较均匀。碱蓬体内重金属含量根据采集地点的不同有差异,但与各站位中土壤的重金属分布特征存在正相关性;其中碱蓬内Fe、Mn、Zn、Cu的平均含量相对较高,且Fe、Mn、Ni、Cu、As、Cd、Pb元素在碱蓬根中的平均含量高于茎叶,而Cr在茎中的平均含量最高,Zn和Mo在叶中的含量最高。碱蓬的根、茎、叶对Cd的富集效果最好,其次为Mo、Cu,对Fe、Mn、Zn、As和Pb的富集效果相对较差,说明碱蓬对沉积物中不同金属元素的富集移出率存在差异。金属元素在碱蓬中的转移系数研究表明,Mo、Zn、Cd和Mn等元素可由根部转移到叶中,而Fe、Ni、Pb、As和Cu等金属元素固定在根部,该研究可为利用碱蓬修复湿地重金属污染提供理论基础。  相似文献   

3.
冬虫夏草中8种矿物元素含量分析   总被引:1,自引:1,他引:0  
利用火焰原子吸收光谱法(FAAS),测定了冬虫夏草中Cu,Zn,Fe,Mn,Mg,Ca,Co以及Cd等8种矿物元素的含量,测定了各元素的加标回收率在98.9%~109.3%之间,相对标准偏差(RSD)小于1.2%,具有良好的准确度和精确度。结果表明,冬虫夏草中含有丰富的Cu,Zn,Fe,Mn,Mg,Ca,Co等多种矿物元素,不含有毒金属元素Cd。  相似文献   

4.
利用火焰原子吸收光谱法测定6种不同产地的湘莲莲子和莲子心中7种金属元素含量. 莲子和莲子心样品经粉碎干燥后, 用硝酸-高氯酸混合液进行消解处理,采用火焰原子吸收光谱法测定样品中Cr、Cu、Zn、Fe、Mn、Pb、Cd的含量. 莲子和莲子心中富含微量元素Fe、Mn、Zn、Cu、Cr,有害金属元素Pb和Cd未检出. 各元素的加标回收率为98.58%~101.53%,RSD在0.78%~1.89%之间. 方法快速、简便、灵敏,结果准确可靠,为莲子和莲子心中金属元素含量测定提供了一种可靠的方法.  相似文献   

5.
目的:明确造成前列舒通胶囊不同批次间差异的标志性无机元素,并进行安全性评价。方法:采用ICP-MS测定制剂中Al、As、B、Ba、Ca、Cd、Co、Cr、Cu、Fe、K、Mg、Mn、Mo、Na、Ni、Pb、Sb、Se、Sn、Sr、Ti、Tl、V、Zn和Hg元素含量并进行数据分析。运用主成分及综合评分结合聚类分析手段,确定制剂的特征性元素;进行元素含量和相关性分析,明确不同批次各元素的差异及元素之间的关系;以多元素含量为指标,绘制无机元素谱图。结果:19批样品中均未检测出Se、Mo、Sn、Sb、Tl和Hg,且Pb、Cd、As、Cu、Hg均符合限量标准,无机元素含量谱图趋势一致。主成分分析提取了4个主成分,确定元素B、K、Al、V、Cr、Ca、Ti、Na、Co和Mn可作为特征元素。主成分得分图将19批样品分为两类,聚类分析及综合评分结果与其一致,两类样品中各元素含量存在差异性。相关性分析中,明确了B与K、Al、Cr正相关,K与Cr、Co正相关,V与Cr、Mn正相关,Mn与Co正相关,Ca、Ti、Na两两正相关。结论:通过分析前列舒通胶囊中无机元素含量,确定了特征元素,为前列舒通胶囊质量全面控制研究提供科学依据。  相似文献   

6.
常见茶叶中14种元素含量分析及重金属风险评价   总被引:1,自引:0,他引:1  
采集传统名茶地标产品样品各3种为实验样品,通过ICP-OES和ICP-MS对样品进行K、Ca、Mg、Mn、B、Cu、Fe、Ni、Zn、Cr、Co、Cd、As、Pb等14种元素的含量测定。利用单因素方差分析、主成分分析、污染评价等方法,对茶叶无机元素含量进行分析和污染评价,并对污染来源进行了研究。结果表明,不同产地茶叶样品中的K、Ca、Mg、Mn、Fe等元素含量差异较大;食品及茶叶安全限量元素Cd、Cr、Pb、As等实测值均未超过国家标准限值;部分元素之间具有正相关性,如Cu与Cd, Cu与Ni, As与Ni两两之间关联性较强;从主成分分析看出Cu、Cd、As和Ni为PC1代表因子,K和Fe分别为PC2和PC3的代表因子,PC1主要代表了金属冶炼、工业排放和垃圾焚烧等方面的贡献,PC2和PC3分别代表了肥料施放和茶叶加工等方面的贡献。  相似文献   

7.
藏药材白花龙胆花中微量元素的分析   总被引:2,自引:0,他引:2  
对藏药材白花龙胆花中17种微量元素(Cu、Zn、Fe、Mn、Co、Ni、Se、Cr、Mg、Ca、K、Na、P、As、Hg、Pb、Cd)的含量作了测定。结果表明,白花龙胆花中含有较高的人体必需微量元素和常量元素,其中常量元素K、Ca、Na、Mg和微量元素Zn、Fe、Mn的含量均较高。  相似文献   

8.
采用体外全仿生消解方法,模拟人体的消化道环境,对牡蛎和蛤仔样品进行仿生消解,分析牡蛎和蛤仔体内微量元素的生物可给性.以原子吸收光谱法测定胃、肠仿生提取液中微量元素的含量.结果表明,牡蛎胃提取液中Fe,Cu,Zn,Cd的含量明显高于肠提取液中的含量,蛤仔胃提取液中Fe,Cu的含量与肠提取液中的含量没有明显差异,而Zn,Cd的含量远高于其在肠提取液中的含量.经全仿生消解后,牡蛎体Fe,Cu,Zn,Cd的可给性分别为60.2%,83.6%,83.1%,76.8%;蛤仔Fe,Cu,Zn,Cd的可给性分别为46.3%,86.3%,85.3%,87.7%.本研究结果为进一步研究牡蛎和蛤仔对金属元素的累积和迁移、生物可利用性,Cd等有害元素对食用者的健康风险评估,提供技术支持和理论依据.  相似文献   

9.
目的分析方杆蕨中微量元素与彝药药性的关系。方法用火焰原子吸收光度法,首次测定方杆蕨中Zn、Fe、Cu、Mn、Pb、Cd元素的含量。结果方杆蕨Zn、Fe、Mn 3种微量元素含量丰富,有害元素Pb、Cd含量未超出国家限量标准。Fe含量是Mn含量的9.5倍,而w(Zn)/w(Cu)为4.6,远低于Bower值11.4。结论方杆蕨中微量元素w(Zn)/w(Cu)值与方杆蕨民间活血化瘀药用是一致的,Fe/Mn值与文献报道高Fe低Mn寒凉类中药元素基础及彝族民间清热解毒药用相符合。  相似文献   

10.
白族长寿地区硬果仁中19种元素的测定分析   总被引:2,自引:4,他引:2  
用电感耦合等离子体发射光谱法(ICP-AES),对云南省白族长寿区的葵花子仁、麻子仁和核桃仁中的Ca、Mg、P、S、Na、AI、B、Fe、Zn、Cu、Mo、Sr、Mn、Cr、Se、Ge、Cd、Pb、As等19种元素进行了测定分析。结果表明,3种硬果仁中含有丰富的人体必需的Ca、Mg、P、S、Na、Fe、Zn、Mn、Se、Cu、Cr、Sr、Mo等有益元素,且P、Mg、S、Ca、Na、Zn、Mn、Fe、Se的含量较高。这些生命元素在3种硬果仁中的含量存在差异。有害元素Cd、Pb均未检出,核桃仁中As含量较高。硬果仁中富含这些生命元素是该地区老人健康长寿的一个重要原因。  相似文献   

11.
In order to bring out the nature of the factors influencing lake water composition, multivariate statistical analysis and trend analysis were performed based on the hydrochemical data of the study area, namely, South Chennai. Change in land use pattern and settlements along the banks of the lakes alters the quality and quantity of the surface water. In the present study, the R‐mode factor analysis and cluster analysis were applied to the geochemical parameters of the water to identify the factors affecting the chemical composition of the lake water. Dendograms of both the seasons give three major clusters, reflecting the groups of unpolluted to moderately polluted, polluted, and heavily polluted stations. The movement of stations from one cluster to another clearly brings out the seasonal variation in the chemical composition of the lake water. The complex hydrochemical data of the surface water were interpreted by condensing them into three major factors. Factor score analysis was used successfully to delineate the stations under study and the role of the contributing factors, and the nature of factors responsible for the variation in chemical composition of the water has been clearly brought out. Results of trend analysis using ArcGIS clearly indicate that the trend in water quality is deteriorating at a faster rate in the eastern part of the study area. It is understood that although natural shifts probably can account for some of the variation, it is most likely that human activities play a major role in affecting the water quality on a regional scale. Copyright © 2014 John Wiley & Sons, Ltd.  相似文献   

12.
This study aims to examine the effect of sodium hydroxide (NaOH) treatment on the physico-chemical properties, structure, thermal, tensile and surface topography of Carica papaya fibers (CPFs). The surface of raw CPFs was modified by soaking with 5% NaOH solution for 15, 30, 45, 60, 75 and 90?min. The results of thermo-gravimetric analysis revealed that the optimum treatment time for alkali treatment was 60?min. It was found that the alkali treatment improved the properties of the CPFs. The results of TGA, FT-IR, XRD and AFM suggest that the treated CPF is a suitable alternative as reinforcement in polymer composites.  相似文献   

13.
On-line fermentation gas analysis is of general interest because it permits the determination of metabolic rates in almost any biological process using living organisms. The consumption and production of gases (O2, CO2, CH4, etc.) and volatile compounds may be determined without causing any risk of infection. Elemental balancing permits the determination of other metabolic rates if the stoichiometry is known. This was studied with the production of poly-β-hydroxybutyrate (PHB) by Alcaligenes latus. Estimations were based on the measurement of gas partial pressure and flow-rates, pH and alkali consumption rate. Experiments with a small quadrupole mass spectrometer showed unacceptable error propagation. Therefore, dynamic error propagation for all rates was studied using simulation. It was found that, for example, a 1% relative offset-calibration error for oxygen can result in an error in PHB estimation of > 50%. It is suggested that this culture is used in combination with elemental balancing for thorough tests of the accuracy of on-line gas analysis equipment. An on-line process gas analyser based on a quadrupole mass spectrometer (Balzers PGM 407) gave the following precision values (abs. vol.?%) during cultivation of Bacillus subtilis: nitrogen (m/z 14), 0.024; oxygen (m/z 32), 0.020; argon (m/z 40), 0.0011; and carbon dioxide (m/z 44), 0.0034. These values, combined with automatic recalibration, would be sufficient for reasonable estimation of PHB, biomass and substrates.  相似文献   

14.
Determining the rank of a chemical matrix is the first step in many multivariate, chemometric studies. Rank is defined as the minimum number of linearly independent factors after deletion of factors that contribute to random, nonlinear, uncorrelated errors. Adding a matrix of rank 1 to a data matrix not only increases the rank by one unit but also perturbs the primary factor axes, having little effect on the secondary axes associated with the random errors in the measurements. The primary rank of a data matrix can be determined by comparing the residual variances obtained from principal component analysis (PCA) of the original data matrix to those obtained from an augmented matrix. The ratio of the residual variances between adjacent factor levels represents a Fisher ratio that can be used to distinguish the primary factors (chemical as well as instrumental factors) from the secondary factors (experimental errors). The results gleaned from model studies as well as those from experimental studies are used to illustrate the efficacy of the proposed methodology. The method is independent of the nature of the error distribution. Limitations and precautions are discussed. An algorithm, written in MATLAB format, is included. Copyright © 2011 John Wiley & Sons, Ltd.  相似文献   

15.
文章介绍了新材料的重要性及发展方向,分析化学在新材料研制中起着耳目的作用,另一方面新材料也为分析化学的进展提供了课题与条件。微量分析、微区分析、表面分析是此领域中的重点。在未来的发展中,分析化学在材料的发展中的地位不会改变,并期待着分析灵敏度与空间分辩率的进一步提高。  相似文献   

16.
多波长K系数法同时测定去痛片中四组分   总被引:1,自引:0,他引:1  
陆晓华  李春华 《分析化学》1991,19(12):1415-1417
  相似文献   

17.
用局部拟合主成分回归计算光度分析法测定黄连生物碱   总被引:1,自引:0,他引:1  
陈闽军  程翼宇  刘雪松 《化学学报》2003,61(10):1623-1627
针对具有样本数据非无匀分布和非线性特点的光度分析问题,提聘种局部拟合 主成分回归法,用于中药多组分计算测定。该方法根据待测样本与各已知样本光度 分析数据的欧式距离确定相应的权值,将部分权值较大的样本组成校正集,并用分 段线性拟合算法建立待测样本的校正预测模型,将其用于分析黄连的药根碱、巴巴 亭和小檗碱等三种生物碱,所得预测均方根误差分别为0.023,0.0400和0.052,优 于主成分回归法、偏最小二乘法以及人工神经元网络法所得结果。这表明,本方法 用于中药光度分析能获得较为准确的计算分析结果。  相似文献   

18.
本文研究了2,3-二氨基萘(DAN)与Se(Ⅳ)反应,生成4.5-苯并苤硒脑(NSD),利用环已烷萃取反应生成的络合物。将有机相注射入填充有μ一Bondapak C_(18)固定相的色谱柱,以环已烷-四氢呋喃(90:10)为流动相,流速为1.0 mL/min,进行HPLC一荧光检测。测定了福建乌龙茶中的微量硒。方法的精密度和回收度均好。检测限达0.12 ng。  相似文献   

19.
双嘧达莫的荧光光谱分析法   总被引:9,自引:0,他引:9  
以荧光光谱法研究了双嘧达莫在溴化十六烷基三甲基铵(CTMAB)、β_环糊精 (β_CD)、十二烷基硫酸钠 (SDS)等介质体系中的荧光性质 ,发现CTMAB、SDS和 β_CD对双嘧达莫均有不同程度的荧光增敏作用 ,提出了在CTMAB、SDS和 β_CD水溶液中测定双嘧达莫的荧光光谱分析法 ;该法灵敏度高 ,检出限低(3.20×10 -9mol/L) ,在6.40×10 -8~3.20×10 -6mol/L范围内荧光强度与双嘧达莫的浓度呈良好线性关系  相似文献   

20.
《Analytical letters》2012,45(6):899-908
Abstract

To determine mercury in geological materials, samples are digested with nitric acid and sodium dichromate in a closed teflon vessel. After bringing to a constant weight, the digest is mixed with air and a sodium chloride-hydroxylamine hydrochloride-sulfuric acid solution and then Hg(II) is reduced to Hg with stannous chloride in a continuous flow manifold. The mercury vapor is then separated and measured using cold vapor atomic absorption spectrophotometry (CV-AAS). For a 100 mg sample the limit of detection is 20 parts per billion (ppb) Hg in sample. To obtain a 1% absorption signal, the described method requires 0.21 ppb Hg solution (equal to 16 ppb in sample). Precision is acceptable at less than 1.2% RSD for a 10 ppb Hg aqueous standard. Accuracy is demonstrated by the results of the analysis of standard reference materials. Several elements do interfere but the effect is minimal because either the digestion procedure does not dissolve them (e.g., Au or Pt) or the; are normally of low abundance (e.g., Se or Te).  相似文献   

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