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1.
测定吉祥草中重金属及有害元素含量,比较不同产地吉祥草中的Cu、Pb、As、Cd、Hg 5种元素的含量.采用原子吸收光谱法测定铅、铜、砷含量,用原子荧光光谱法测定汞、镉含量.吉祥草药材中汞、镉、砷含量均低于国家限量标准,个别地区吉祥草药材中铜、铅含量高于国家限量标准.本文为科学地制定吉祥草药材中重金属限量标准,提高吉祥草...  相似文献   

2.
玩具中有害重金属元素的ICP-AES分析   总被引:3,自引:0,他引:3  
本文介绍了利用ICP-AES对玩具中有害重金属元素的分析研究。文中详述了实验方法,适用范围以及结果和讨论,并运用干扰系数法校正元素间光谱干扰,结果较为满意,这在玩具日常检测的光谱分析中具有重要的实际意义。  相似文献   

3.
张岚  刘莹  宋春梅 《光谱实验室》2010,27(3):888-891
ICP-AES测定长白山酸浆果实中18种无机元素。在酸浆果实所测定的无机元素中,含量依次为KPMgCaFeZnMnCuSnAlNiMoCr,其中V、Co含量均0.1mg/kg;Pb、Hg、Cd等有害重金属含量极低或未检出。该法相对标准偏差为0.14%—3.57%。  相似文献   

4.
采用微波消解-电感耦合等离子体-原子发射光谱仪测定了五香粉中Cu、Zn、Fe、Mn、Cd、Pb 6种重金属元素的含量.结果表明,五香粉中Cu、Zn、Fe、Mn等人体必需微量元素含量丰富,而对人体有害的Cd和Pb含量较少.该方法的加标回收率在95.0%-106.3%之间,相对标准偏差小于3%,具有较好的准确度和精密度.  相似文献   

5.
铬、砷、硒、镉、锑、钡、汞和铅8种有害元素是玩具安全领域必检项目。目前,标准方法大多需采用湿化学法处理样品,再用仪器进行测试,前处理过程复杂,耗时长、成本高。EDXRF法具有无须样品前处理、对样品非破坏性、成本低、效率高等优点,已广泛用于电子电气产品中有害物质的快速筛选分析,但由于玩具材料和待测元素种类多,大多元素限量较低,目标元素间存在重叠干扰,导致难以准确测试,尚未见应用于玩具中8种有害元素的测定。通过研究分析线、滤光片、管电压、分析时间等测试条件的选择和样品厚度对结果的影响,并根据目标元素的特性,确定了最佳的3种条件组合方式。通过经验系数法校正了塑料中分析元素相互之间引起的吸收-增强效应,利用Rh康普顿散射线作为内标校正了样品的颗粒度效应,并通过干扰重叠系数法校正了元素间谱线重叠干扰。根据玩具常用塑料样品基体类型特性,选用聚乙烯(PE)和聚氯乙烯(PVC)两类塑料标准样品分别制作工作曲线,建立了EDXRF法快速测定玩具塑料中8种有害元素含量的新方法。各元素在7.6~1 298 mg·kg-1范围内线性良好,方法检出限在0.5~37 mg·kg-1之间,能够满足目前玩具安全标准限量筛选要求。采用PP,PE,ABS和PVC等不同玩具塑料样品验证了方法的准确度和精密度,并将样品测试结果与样品参考值比较,计算相对误差均在25%以内,除某样品中个别元素RSD(n=6)在9%~15%稍大外,其他样品各元素的RSD(n=6)均在6%以内,精密度较好。如将单个条件的测试时间从30 s延长到2 min后,所有样品测定结果RSD均可降至5%以下。本方法操作简便、成本低、快速、准确,可用于玩具塑料中有害元素的快速筛选分析。  相似文献   

6.
微波消解等离子体发射光谱法测定苹果中的多元素分布   总被引:1,自引:0,他引:1  
以市售红富士苹果为实验材料,采用微波消解,ICP-AES测定苹果中14种微量元素在果皮和果肉的分布情况。结果显示,苹果皮的有益矿物质元素和有害重金属(Cr,AS,Pb,Sn)含量均比苹果肉高。说明重金属被植物吸收以后,容易在果皮积累,果肉中含量较少。  相似文献   

7.
微波消解/ICP-MS法测定川黄柏中微量重金属元素   总被引:7,自引:2,他引:7  
采用微波消解技术,建立了一种测定道地药材川黄柏中Co,Ni,Cu,Zn,As,Cd,Hg和Pb等八种微量重金属元素的ICP-MS法.用国家一级标准物质杨树叶(GBW-07604)和茶叶((3BW-07605)标准物质评价了方法的准确性.应用拟定的分析方法测定了不同地区(巴中、宜宾与荥经)、不同生长期(荥经:6年、8年10年)的川黄柏中微量重金属元素的含量.方法对试样中各元素测定的相对标准偏差范围为3.2%~17.8%,回收率在70%~120%之间.研究表明,方法简便、快速、灵敏,适合于川黄柏中八种微量重金属元素的测定.同时,试样分析结果显示,川黄柏中有害重金属元素As,Cd,Hg和Pb的含量均低于<中国药典>及<药用植物及制剂进出口绿色行业标准>的限量标准,宜于药用和出口.  相似文献   

8.
利用微波消解技术处理样品,采用原子吸收光谱法测定了我国广东、湖北、湖南、重庆、广西、江苏、福建、浙江、安徽九个不同产区淡竹叶中Zn,Fe,Cu,Mn,K,Ca,Mg,Ni,Cd,Pb,Cr,Co,Al,Se,As 15种微量元素的含量。该方法的相对标准偏差(RSD)在1.23%~3.32%之间,平均回收率在95.8%~104.2%之间。研究表明,该方法简便、快速、灵敏,适合于淡竹叶中微量元素的测定。试验分析结果表明,不同产地淡竹叶中微量元素的含量呈现地域性差异。各地区的淡竹叶中对人体有益的元素K,Mg,Ca,Fe,Mn含量普遍较丰富;对人体有害的重金属元素,除湖南产的淡竹叶中Pb的含量稍高,广东、安徽产的淡竹叶中Cu的含量偏高外,其他产区的淡竹叶中有害重金属元素Cd,Cu,Cr,Pb,As的含量均低于《中国药典》、《药用植物及其制剂进出口绿色行业标准》及《国家标准食品卫生标准》的限量标准。该测定结果为进一步探讨淡竹叶中微量元素的含量与其功效的相关性提供了科学依据。  相似文献   

9.
采用电感耦合等离子体发射光谱法(ICP-OES)测定棕熊肉中有益金属元素与重金属元素的含量。熊肉中含有Ca、K、Na、Mg、Zn、Fe、Ti等7种有益金属元素,Cu、Al、Tl、Cr等4种有害金属元素。该方法对各元素的检出限为0.0002—0.006mg/L,各元素相对标准偏差在1.12%—6.19%之间,加标回收率为96.8%—104.9%。11种金属元素中Na、Mg、Fe、K、Ca的含量较高。  相似文献   

10.
对天然紫皮石斛(Dendrobium devoninum Paxt.)根和茎中Cr、Cd、Pb、Hg、Cu 5种重金属元素的含量进行了测定,旨在为该资源的药(食)利用提供基础数据.利用干法灰化处理样品,采用原子吸收光谱法(AAS)分别测定紫皮石斛根和茎中Cr、Cd、Pb、Hg、Cu 5种重金属元素的含量.根中Cr、Hg和Cu 3种元素含量分别为122.8043士39.02、311.5152士24.28、0.2890士0.19mg·kg-1,相对标准偏差(RSD)在3.20%-14.07%之间;茎中Cr、Hg和Cu 3种元素的含量分别为139.3997士14.72、276.0101士45.61、0.2854士0.29mg·kg-1,相对标准偏差(RSD)在4.83%-10.99%之间;根和茎中均未检出Cd、Pb两种元素,可能与地球化学背景有关.与人工种植石斛中重金属元素含量相比,Cr、Hg两种元素含量相对较高,Cu元素含量较低.本法操作简便,重复性好,测定结果满意.  相似文献   

11.
ABSTRACT

A simple and reliable method for Cd determination in plastic materials using optimized wet acid digestion procedure and atomic absorption spectroscopy was developed. In order to obtain the best experimental conditions for plastic digestion, a 27–4 Plackett-Burman design for screening the significant factors and a 24–1 central composite design to optimize the significant experimental variables were carried out. The polyethylene European Reference Material ERM-EC680 with certified Cd content was used in both the screening and the optimization steps. The optimized experimental conditions 0.200 g of plastic material digested with 2 mL nitric acid (30 min, 130°C) followed by 1 mL sulfuric acid (30 min, 140°C). The accuracy and precision was checked using ERM-EC680. The Cd recovery was 101.3% and the relative standard deviation was 5.6%. The limit of detection obtained was 0.23 mg kg?1. The method was applied in the analysis of one PVC plastic material, several commercial packaging materials, and plastic toys.  相似文献   

12.
束琴霞  邹勇平 《光谱实验室》2012,29(4):2473-2476
采用了氢化物发生-原子荧光光谱法对扬州毛绒玩具中的汞(Hg)和硒(Se)进行同时测定。在0—10μg/L范围内汞和硒的浓度与荧光强度呈线性关系,相关系数分别为0.9999和0.9998,加标回收率分别达到88%—95%和92%—109%,汞、硒测定结果的RSD分别不大于3.83%和3.70%。  相似文献   

13.
ATLC spectrodensitometric procedure was developed for the determination of methyl paraben, propyl paraben, sorbic acid and benzoic acid as bulk powders or in pharmaceutical dosage forms and foods. The procedure was used for the determination of the two parabens singly or together and also was used for the determination of benzoic and sorbic acids singly because they were found singly in some commercial food and pharmaceutical products. The cited compounds were separated on silica gel with fluorescent indicator in systems, acetone-ethanol-aqueous ammonia 28%-ethyl acetate (84:3:9:9) for the determination of benzoic and sorbic acids and n-hexane-ethyl acetate-acetic acid (80:5:20) for the determination of the two parabens. Absorbance measurement (detection of reflectance) of separated compounds was carried out in situ, at 254 nm for the two parabens, sorbic acid, and at 228 nm for benzoic acid using multilevel calibration curves in the concentration ranges of 0.2—2.5 μg/spot, 0.5—3 μg/spot, and 2.5—12.5 μg/spot for sorbic acid, the two parabens, and benzoic acid, respectively. The results were evaluated by linear regression analysis. The mean % accuracies were found to be, mean ±C.V.(%), 99.65 ±0.963, 99.45±1.02, 99.60±0.825 and 99.34±0.969 for benzoic acid, sorbic acid, methyl paraben and propyl paraben in bulk powders, respectively. While in case of benzoic and sorbic acids in foods the mean % accuracies were found to be: 97.72±1.231 and 98.81±1.296, respectively. The mean % accuracies of methyl paraben, propyl paraben, sorbic acid in pharmaceutical dosage forms were found to be: 98.19±0.874, 97.830±0.799 and 98.36±0.572, respectively.  相似文献   

14.
In the early 1960s, a PhD student in physics, Costas Papaliolios, designed a simple—and playful—system of Polaroid polarizer filters with a specific goal in mind: explaining the core principles behind Julian Schwinger’s quantum mechanical measurement algebra, developed at Harvard in the late 1940s and based on the Stern-Gerlach experiment confirming the quantization of electron spin. Papaliolios dubbed his invention “quantum toys.” This article looks at the origins and function of this amusing pedagogical device, which landed half a century later in the Collection of Historical Scientific Instruments at Harvard University. Rendering the abstract tangible was one of Papaliolios’s demonstration tactics in reforming basic teaching of quantum mechanics. This article contends that Papaliolios’s motivation in creating the quantum toys came from a renowned endeavor aimed, inter alia, at reforming high-school physics training in the United States: Harvard Project Physics. The pedagogical study of these quantum toys, finally, compels us to revisit the central role playful discovery performs in pedagogy, at all levels of training and in all fields of knowledge.  相似文献   

15.
建立了高效液相色谱法同时测定养心草中没食子酸、槲皮素和山萘酚的含量。采用Hypersil C18色谱柱(4.6mm×200mm,5μm),流动相为甲醇(A)-0.2%磷酸水溶液(B),梯度洗脱,流速1.0mL/min;柱温25℃;检测波长260nm。在选定色谱条件下没食子酸、槲皮素和山萘酚线性关系良好;没食子酸、槲皮素和山萘酚加标回收率分别为98.37%、99.61%、97.81%,RSD分别为2.32%、2.15%、2.20%。方法简便快速,结果准确可靠,可用于控制中药养心草的质量。  相似文献   

16.
根据高斯光束的传输特性,搭建了一套测量电玩具中LD和LED光束质量和光斑尺寸的测量系统。该系统以CCD作为光斑采集的关键设备,利用自行编写的软件同步控制CCD和数控位移平台,采集LD和LED所发出光束在不同位置的光强分布图样。利用二阶矩计算光束的束宽,并由双曲线拟合得到光束轮廓曲线,计算出光束的M2因子,进而推算出LD和LED光束任一位置的光斑尺寸,实现对电玩具中LD和LED发光光斑尺寸的精确测量。  相似文献   

17.
原子吸收光谱法测定小白鼠脑组织中Na,K,Ca   总被引:2,自引:0,他引:2  
本文利用空气-煤气火焰或空气-乙炔火焰原子吸收光谱法分别测定小白鼠脑组织中Na,K,Ca。样品用HNO3-KClO4体系消化。用LaCl3消除P对Ca的干扰,以CsCl作Na,K的消电离剂。共测定了4组46个不同代表性的样品,测定Na,K,Ca的相对标准偏差(RSD)分别为0.886%,0.691%和0.824%,加标回收率分别为100.6%,102.0%和98.4%。  相似文献   

18.
In this study, ultrasonic/microwave-assisted extraction (UMAE), microwave-assisted extraction (UAE), ultrasound-assisted extraction (UAE), and pressurized liquid extraction (PLE) were applied to extract green coffee oil (GCO), and the physicochemical indexes, fatty acids, tocopherols, diterpenes, and total phenols as well as antioxidant activity of GCO were investigated and compared. The results indicated that the extraction yield of UMAE was the highest (10.58 ± 0.32%), while that of PLE was the lowest (6.34 ± 0.65%), and linoleic acid and palmitic acid were the major fatty acids in the GCO, ranging from 40.67% to 43.77% and 36.57% to 38.71%, respectively. A large proportion of fatty acids and phytosterols were not significantly influenced by the four extraction techniques. However, tocopherols, diterpenes, total phenols, and the free radical scavenging activity were significantly different among these four GCOs. Moreover, structural changes in the coffee residues were explored by scanning electron microscopy and Fourier transform infrared spectroscopy. Overall, the high antioxidant activity of GCO demonstrated that it can be used as a highly economical natural product in the food and agricultural industries.  相似文献   

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