共查询到20条相似文献,搜索用时 109 毫秒
1.
采用钯,钯-镁作基体改进剂,FIA-HG-GFAAS法成功地测定了锗。灵敏度,精密度和分析速度都得到很大的提高,峰值吸收的特征质量8.0pg,检出限10.9pg,相对标准偏差0.34%,同时探讨了基体改进剂钯的稳定作用机理及锗在石墨管中的原子化机理。 相似文献
2.
3.
石墨炉原子吸收法,涂钼热解管,Pt-Ni混合基体改进剂,Zeeman效应扣除背景,在1400℃灰化温度下直接测定锗,方法简单,结果满意。特征质量为20.3pg/0.004A。 相似文献
4.
石墨炉原子吸收法测定人体血尿和尿中锗 总被引:3,自引:0,他引:3
研究了口服有机锗后人体血浆及尿中锗的测定方法。以5%三氯乙酸溶液沉淀血蛋白,离心分离后,取上清液测定。以钯和硝酸镍混合溶液做基体改进剂,提高灰化温度至1400℃,消除了样品中大量基体对测定锗的干扰,方法特征量为31pg,检出限为28pg(3σ),样品加标准回收率为:血浆91.4% ̄97.0%,尿97.2% ̄105%。 相似文献
5.
平台石墨炉原子吸收法测定高温镍基合金中砷 总被引:6,自引:0,他引:6
研究了基体改进剂,灰化,原子化温度和共存元素的干扰。采用钯作基体改进剂和匹配基体镍后,提高了灵敏度,增强了抗干扰能力。在波长197.2nm处,用平台石墨炉原子吸收法直接测定了高温镍基合金中砷。方法特征是为88pg,检出限为0.27μg.g^-1,相对标准偏差为3.1%-5.1%,回嵋率为85%-100%。 相似文献
6.
病人血样中痕量锗,锶的石墨炉原子吸收光谱法测定 总被引:2,自引:1,他引:2
本文运用石墨炉AAS法加基体改进技术,测定了50岁以上病人血清及环境水样中锗和锶的含量。用0.01mol/LHNO3-0.1%TritonX-100稀释血清,测定精度可与火焰法媲美。锗,锶的特征量分别为28pg和18pg;线性范围为0-250ng/mL和-35.0ng/mL;相对标准偏差(n=10)4.10%和2.49%;回收率分别为92.2%-99.0%和92.0%102%。方法快速准确,结果满 相似文献
7.
溶剂萃取石墨炉原子吸收光谱测定盐卤中痕量铷 总被引:6,自引:0,他引:6
采用石墨炉原子吸收光谱(GFAAS)研究盐卤中铷的原子化行为和机理,建立了热解石墨管,KNO3-NH4NO3基体改进剂,18-冠-6,溴百里香酚蓝,氯仿萃取分离GFAAS测定盐卤铷的方法。用于测定盐卤中痕量铷,特征质量1.1×10^-10g/0.0044,加标回收率89% ̄110%;相对标准偏差6.28%(n=13)。 相似文献
8.
本文采用GF-AAS加平台技术,基体改进剂,测定了中药片仔癀,六味地黄丸中铬、铅和镉的含量,铬、铅和镉的线性范围分别为0-0.8ng/mL,0-50ng/mL,0-5ng/mL,回收率分别为102-103%,99-101%,97.5-98%,本方法简便快速、准确。 相似文献
9.
平台石墨炉原子吸收法测定高温镍基合金中铋 总被引:3,自引:0,他引:3
本文用1mg/mL镍和0.2mg/mL钯作混合基体改进剂,提高了测定铋的灰化温度和抗干扰能力,且灵敏度几乎不变。可不经分离样品基体,直接用平台石墨炉原子吸收法测定高温镍基合金中铋。方法特征量为18pg,检出限为0.081μg/g。对含0.3-0.7μg/g铋的镍基样品测定,相对标准偏差为3.0%-5.9%,回收率在85%-119%之间。 相似文献
10.
报道了一种对钯离子具有高灵敏度和选择性的新试剂2-(2-噻唑偶氮)-5-[(N,N-二羧基甲基)氨基]苯甲酸(TADCAB)。在0.5mol/LHNO_3介质中,TADCAB与Pd(Ⅱ)形成蓝色配合物,组成为Pd:TADCAB=1:2,最大吸收波长652nm。钯浓度在0~1.4μg/mL范围内符合比耳定律。用双波长法测定,表观摩尔吸光系数ε_(652.0~533.6)=8.2×10 ̄4L·mol ̄(-1)·cm ̄(-1),可以允许大量金属离子共存。所确立的方法无需掩蔽剂和其它分离手段,即可直接用于Pt-Pd催化剂中微量钯的测定,结果满意。 相似文献
11.
The part of palladium in ambient urban air that is bound to particles and soluble in aqua regia was determined by means of sorbent extraction, coupled with graphite furnace atomic absorption spectrometry (GFAAS) and laser absorption fluorescence spectrometry (LAFS). Samples of about 200 m3 air were taken in a suburb of Berlin, Germany. The coupling of the selective and automated pre-concentration procedure for Pd as N,N-diethyl-N'-benzoylthiourea complex with the respective detection methods proved to be sufficiently sensitive. Severe interference with other matrix constituents, occurring mainly by direct LAFS detection, could be overcome and the detection limit was improved tremendously. The concentration of Pd in ambient air was determined to be in the range from 0.2 to 14.6 pg/m3. 相似文献
12.
H. Alsenz F. Zereini C. L. S. Wiseman W. Püttmann 《Analytical and bioanalytical chemistry》2009,395(6):1919-1927
The concentration of platinum group elements (PGE) in the environment has increased significantly in the last 20 years mainly
due to their use as catalysts in automotive catalytic converters. The quantitation of these metals in different environmental
compartments is, however, challenging due to their very low concentrations and the presence of interfering matrix constituents
when inductively coupled plasma-mass spectrometry (ICP-MS) is used for analysis. Previously, the research focus was on the
analysis of platinum (Pt) and rhodium (Rh). However, due to the increasing use of palladium (Pd) in automotive catalytic converters,
quantitation of this element in airborne particulate matter (PM) is also needed. Compared to Pt and Rh, measurements of Pd
using ICP-MS are plagued by greater molecular interferences arising from elements such as copper (Cu), zinc (Zn) strontium
(Sr), yttrium (Y), and zirconium (Zr). The aim of this study was to evaluate the applicability of reductive co-precipitation
procedures using both mercury (Hg) and tellurium (Te) for the pre-concentration of Pd from airborne PM. Furthermore, helium
(He) was tested as a collision gas for isotope dilution-inductively coupled plasma-quadrupole-mass spectrometry (ID-ICP-Q-MS)
to measure Pd in the Hg and Te precipitates. Airborne PM samples (PM10) were collected from Neuglobsow (Brandenburg, north-eastern Germany) and Deuselbach (Rhineland-Palatinate, south-western
Germany), considered to represent background levels, and from the city Frankfurt am Main (Hesse, Germany), a high-traffic
area. Samples were first digested with aqua regia in a high-pressure asher (HPA) at 320 °C and 130 bar prior to the application of reductive co-precipitation procedures. The
method was validated with road dust reference material BCR-723 and the CANMET-CCRMP reference material TDB-1 and WPR-1. In
airborne PM collected at the background areas Neuglobsow and Deuselbach, Pd was detected with median concentrations values
of 0.5 and 0.6 pg/m3, respectively. Much higher median concentration values of 14.8 pg Pd/m3 (detection limit = 0.01 pg Pd/m3) were detected in samples collected in the city of Frankfurt am Main. Results have shown that Hg co-precipitation depletes
the concentrations of interfering matrix constituents by at least one order of magnitude more, compared to Te co-precipitation,
making it a more effective method for the isolation and pre-enrichment of Pd from airborne PM prior to analysis. The use of
a He gas flow of 120 ml/min in the plasma further minimized interferences, particularly those arising from CuAr+, YO+, and ZrO+ during the determination of Pd. The results demonstrate that Hg co-precipitation and the use of He collision gas, in combination
with isotope dilution, are highly effective methods for the quantitation of Pd in airborne PM using ICP-MS.
相似文献
13.
应用Pd(NO3)2-抗坏血酸(Vc)基体改进剂,建立了石墨炉原子吸收法(GFAA法)测定土壤和沉积物样品中铊。针对土壤和沉积物复杂基体,GFAA法测定铊元素主要受到氯离子的干扰,文中研究了常见基体改进剂(包括NH4NO3,(NH4)2SO4,La(NO3)3,Mg(NO3)2,Vc,Pd(NO3)2,Pd(NO3)2-Vc)对氯离子的抑制效果。通过研究不同基体改进剂测定含氯铊标准溶液的吸收曲线,探讨出基体改进剂测定铊的作用机理。以土壤或沉积物标准物质为研究对象,优化了应用Pd(NO3)2-Vc测定铊的灰化温度、基改剂浓度以及原子化温度。在最佳实验条件下,通过比较有无基体改进剂条件下,采用GFAA法测定不同土壤和沉积物中铊的精密度和准确度,实验结果表明,应用Pd(NO3)2-VC基体改进剂,测定土壤和沉积物标准物质中铊的测定结果都在标准值范围之内,6次平行测定的相对标准偏差范围为2.8%~8.4%,用于测定实际土壤和沉积物样品加标回收率为128.0%和92.9%。 相似文献
14.
N. A. Yashtulov S. S. Gavrin A. A. Revina V. R. Flid 《Russian Chemical Bulletin》2010,59(8):1482-1487
Palladium nanoparticles on the porous silicon were synthesized by radiation-chemical reduction in the solution of reversed
micelles. The Pd nanoparticles obtained are electron deficient. The porosity, the type of conductivity, the silicon matrix
pore geometry, and precursor parameters influence the size, the shape and the charge state of palladium catalysts. The mechanism
of H2 and HCOOH electrooxidation on porous silica in the presence of Pd+/Pd redox pair is proposed. 相似文献
15.
The part of palladium in ambient urban air that is bound to particles and soluble in aqua regia was determined by means of sorbent extraction, coupled with graphite furnace atomic absorption spectrometry (GFAAS) and laser absorption fluorescence spectrometry (LAFS). Samples of about 200 m3 air were taken in a suburb of Berlin, Germany. The coupling of the selective and automated pre-concentration procedure for Pd as N,N-diethyl-N’-benzoylthiourea complex with the respective detection methods proved to be sufficiently sensitive. Severe interference with other matrix constituents, occurring mainly by direct LAFS detection, could be overcome and the detection limit was improved tremendously. The concentration of Pd in ambient air was determined to be in the range from 0.2 to 14.6 pg/m3. 相似文献
16.
Electrodeposition and characterization of Pd nanoparticles doped amorphous hydrogenated carbon films
Palladium (0) nanoparticles incorporated hydrogenated amorphous carbon (Pd/a-C:H) films were synthesized on single crystal silicon (100) substrates by electrochemical deposition route using methanol and camphor as carbon source, and Pd nanoparticles as dopant. The characterization results indicate that Pd nanocrystalline particles with diameter in the range of 1–5 nm dispersed in the amorphous carbon matrix. Compared with pure a-C:H films, the introduction of Pd nanoparticles didn't change the structure of carbon films. At the end, the growth mechanism of the Pd/a-C:H composite films was discussed. 相似文献
17.
The gold‐palladium (Au?Pd) bimetallic nanocluster (NC) catalyst in colloidal phase performs the homocoupling reaction of various aryl chlorides (Ar?Cl) under ambient conditions. We have systematically investigated various aspects of the Au?Pd NC catalysts with respect to this homocoupling reaction by using density functional theory (DFT) calculations, genetic algorithm (GA) approaches, and molecular dynamics (MD) simulations. Our findings include the geometric and electronic structures of the Au?Pd NC, the reactive Pd sites on the NC surface, the electron‐donating effects of surrounding polymer matrix, the reaction mechanism of homocoupling reaction and rate‐determining step, the inverse halogen dependence of the reaction, and the solvation dynamics at interface region between NC and polymer matrix in aqueous solution. 相似文献
18.
The mechanism of palladium matrix modification is studied for the determination of lead and bismuth by graphite-furnace atomic absorption spectrometry. The binding energies of the charring products for lead and bismuth in the presence or absence of palladium obtained at the initial stage of atomization were measured. The binding energies indicated the formation of PbPd and BiPd bonds, thus explaining the increase in appearance temperatures of lead and bismuth in the presence of palladium. 相似文献
19.
Waxes were separated from needles by chloroform washing, drying and dissolving the residue in tetrahydrofuran (THF). Both
a THF solution of the wax and an aqueous solution of the Pd-Mg matrix modifier were sampled directly into the graphite tube.
The reaction conditions were optimised for the wax concentration of 45 mg ml-1 in THF and the Pd:Mg ratio of 1:1 in the matrix modifier. The atomisation and charring temperatures for As, Cd and Pb were
the same as those recommended for analysis of aqueous solutions except the charring temperature of Cd takes 200 °C lower.
The characteristic masses for As (26 pg), Cd (0.5 pg) and pb (9 pg) are also comparable to published data. The parameters
of calibration curves were identical for all three elements dissolved either in clear THF or in the wax solution. Elemental
concentrations were found to range from 0.1 to 1.0 mg g-1, increasing with needle age for As, Pb but not Cd.
Received: 20 September 1996 / Revised: 14 November 1996 / Accepted: 13 December 1996 相似文献
20.
Chunfu Zhang Yongxian Wang Haibin Tian Duanzhi Yin 《Journal of Radioanalytical and Nuclear Chemistry》2002,253(2):313-316
A method for 103Pd molecular plating onto the surface of the copper rod is reported. The optimal composition of the plating bath was: palladium chloride 2 g/l, ammonium hydroxide (28%) 150 ml/l, sodium hypophosphite 12 g/l, and ammonium chloride 37 g/l. The whole procedure of 103Pd molecular plating will last 50 minutes at 40 °C. This article provides valuable experience for the preparation of 103Pd seeds. 相似文献