等离子体质谱法测定地质样品中痕量稀土元素的基体效应 …

采用模拟地质样品中稀土元素间天然组成比的基体匹配校正标准溶液进行外标校正,有效地抑制了地质样品分析中的基体效应,以＾１１５Ｉｎ－＾１０３Ｒｈ双内标元素校正,监控和校正分析信号的短期和长期漂移;通过单个稀土元素及钡的氧化物,氢氧化物的测定计算出等效的干扰浓度,进而校正了稀土元素分析中多原子离子干扰。建立了地质样吕吕痕量稀土元素测定中基体效应及多原子离子干扰的校正方法。通过对５个标准参考物质的分析,定     

电感耦合等离子体质谱准确测定单斜辉石中稀土元素

采用密闭酸溶ICP-MS研究了单斜辉石中稀土元素准确分析方法.以基体匹配的混合标准溶液为外标校正溶液;利用115In-103Rh双内标校正系统;并通过单个稀土元素及钡的氧化物、氢氧化物的测定,计算出等效干扰浓度进行校正,从而有效地抑制了分析信号的漂移、基体效应及多原子离子干扰.通过对4个标准参考物质的分析,测定结果与推荐值一致.该法应用于4个单斜辉石样品分析,方法检出限为0.7～2.5 ng·L-1,RSD≤10%(n=5).     

珍珠中痕量稀土元素的ICP-MS测定及其分布特性

探讨了等离子体质谱(ICP-MS)分析珍珠样品中稀土元素的基体效应及多原子离子干扰,并采用干扰校正因子进行有效的校正,以In-Rh双内标校正体系进行分析信号动态漂移的监控和补偿,建立了珍珠样品中稀土元素的ICP-MS分析方法。方法的定量检出限为0．1～0．5ng／g,RSD≤15％(n=5)。所建立的方法用于标准物质Gui-1、Gui-2、Gui-3及人工养殖珍珠的分析。珍珠中稀土元素的分布与分馏特性与其生长环境密切相关。     

电感耦合等离子体质谱测定地质样品中多种元素

用电感耦合等离子体质谱(ICP-MS)测定了地质样品中多种元素。考察了测量过程中的基体效应及质谱干扰,利用In内标,补偿由于基体效应的影响所引起的测量偏差,建立校正公式校正质谱干扰。方法的检出限为0.06~250ng/L,精密度为1.7%~3.2%,加标回收率为91%~108%,方法适于批量地质样品分析。     

中国稀土科技文献索引(2001)

6 37　 用ＤＨＥＤＣＭＰ在逆流色谱上分离镧系金属离子 ,金玉仁等 ,化学学报 ,2 0 0 0 ,5 8(6 ) ,6 92 .6 38　 等离子体质谱法测定地质样品中痕量稀土元素的基体效应及多原子离子干扰的校正研究 ,故圣虹等 ,高等学校化学学报 ,2 0 0 0 ,2 1(3) ,36 86 39　ＺｒＯ2 Ｙ2 Ｏ3 Ａｌ2 Ｏ3 系统的拉曼光源 ,谷晋骐等 ,天津大学学报 ,2 0 0 0 ,33(6 ) ,795 .6 4 0 　 红外法测定富镧混合稀土中磷和硫 ,王颖娥 ,理化检验 (化学分册 ) ,2 0 0 0 ,36 (5 ) ,2 2 8.6 4 1　 感耦等离子体质谱法直接测定碳酸盐中超痕量稀土元素 ,胡圣虹等 ,岩矿测试 ,…     

微波消解ICP-MS测定烟草中痕量稀土元素

采用微波消解ICP-MS测定了烟草中痕量稀土元素,探讨了采用115In-103Rh双内标元素校正系统对分析信号漂移的补偿作用及利用干扰校正因子进行氧化物及多原子离子干扰的校正,方法的检出限为0.7~2.5 ng.L-1,测定下限为0.1~0.49 ng.g-1,RSD≤15%。用于不同产地的烟草中稀土元素分析表明,稀土元素的分布特性及分馏规律与当地的土壤环境有着密切的相关性,可用于烟草源区的定性判别和鉴定。     

ICP-MS测定高纯氧化铒中稀土杂质的研究

从同位素的选择、基体效应,内标元素的选择及仪器工作等方面对实验参数进行了优化,重点研究了等离子体功率及仪器分辩率的改变对铒基体所形成的氢化物多原子离子干扰的影响。通过提高等离子体功率、改变仪器分辨率及数学方程校正等方法,减小和剔除了ErH对Ho和Tm测定的干扰。实验中选取Cs为内标元素,测定了不同含量的高纯氧化铒样品。分析结果与标准加入法结果进行了比较,之间无显著性差异。     

电感耦合等离子体质谱(ICP-MS)法测定地质样品中Cu和Zn的干扰研究

电感耦合等离子体质谱(ICP-MS)法标准模式测定地质样品中Cu和Zn时,样品溶液中Ti在高温下易形成TiO⁺和TiOH⁺产生离子重叠干扰,使测定值偏离真值而影响测定结果。采用氢氟酸-高氯酸-硝酸消解、王水复溶样品,通过多级在线校正⁴⁶Ti¹⁶O⁺,消除TiO⁺和TiOH⁺离子重叠干扰,研究了单质Ti与⁴⁶Ti¹⁶O⁺、质荷比63、64、65、66离子间存在的关系,建立了一种电感耦合等离子体质谱(ICP-MS)法测定地质样品中Cu和Zn的分析方法。结果表明：单质Ti对Cu和Zn产生的干扰值与其质量浓度呈非简单的正相关性,TiO⁺产生的干扰离子质荷比65离子强度比63高,质荷比64离子强度比66高;⁴⁶Ti¹⁶O⁺对质荷比63、66离子干扰增量值与单质Ti质量浓度变化无关;^6...     

电感耦合等离子体质谱法(ICP-MS)测定高纯氧化铒中稀土杂质

从同位素的选择、基体效应,内标元素的选择及仪器工作条件等方面对实验参数进行了优化,重点研究了等离子体功率及仪器分辨率的改变对铒基体所形成的氢化物多原子离子干扰的影响。通过提高等离子体功率、改变仪器分辨率及数学方程校正等方法,减少和剔除了ErH对Ho和Tm测定的干扰。实验中选取Cs为内标元素,测定了不同含量的高纯氧化铒样品。分析结果与标准加入法结果进行了比较,之间无显著性差异。     

微波消解-电感耦合等离子体质谱法测定地质样品中稀土元素

建立了微波消解-电感耦合等离子体质谱(ICP-MS)测定地质样品中稀土元素的方法,采用HNO3-HF体系-微波消解进行样品前处理,经赶酸后再用5 m L 1∶1 HNO3提取,整个过程安全、高效、无损失。利用ICP-MS进行测定,可以有效降低多原子离子质谱干扰,在优化仪器参数后,用内标铑(Rh)进行校正,弥补基体抑制效应和灵敏度漂移,测试结果更加准确。方法用于岩石标准物质(GBW07109,GBW07110和GBW07111)测试,其测定值与标准值相一致。结果表明,该方法的检出限低,准确度高,操作简单快捷,可同时测定多种元素,能满足批量测定地质样品中稀土元素含量的要求。     

电感耦合等离子体质谱法对GSS系列土壤及沉积物标准物质中多种元素的定值

介绍对10种GSS系列土壤及沉积物标准物质中多种元素进行定值的方法和结果，采用模拟土壤元素天然组成比值的校正溶液，对元素间的基体干扰具有明显的抑制作用，利用115In-103Rh双内标元素校正系统，可有效地抑制分析信号的动态漂移，建立了电感耦合等离子体质谱法对土壤及沉积物标准的物质中多种元素定值的方法，用该方法对GSS－4，GSS－5，GSS－8及GSD－9共4种土壤标准物质进行测定，绝大部分元素的测定结果与标准值的相对误差小于10％，相对标准偏差小于10％，对GSS－10－GSS－16，AMS－1，BEM及DMS－1共10种土壤及沉积物待定值标准物质进行定值，绝大部分元素测定结果的相对标准偏差小于10％。     

Gas-phase oxidation of Cm+ and Cm2+ --thermodynamics of neutral and ionized CmO

Fourier transform ion cyclotron resonance mass spectrometry was employed to study the products and kinetics of gas-phase reactions of Cm (+) and Cm (2+); parallel studies were carried out with La (+/2+), Gd (+/2+) and Lu (+/2+). Reactions with oxygen-donor molecules provided estimates for the bond dissociation energies, D[M (+)-O] (M = Cm, Gd, Lu). The first ionization energy, IE[CmO], was obtained from the reactivity of CmO (+) with dienes, and the second ionization energies, IE[MO (+)] (M = Cm, La, Gd, Lu), from the rates of electron-transfer reactions from neutrals to the MO (2+) ions. The following thermodynamic quantities for curium oxide molecules were obtained: IE[CmO] = 6.4 +/- 0.2 eV; IE[CmO (+)] = 15.8 +/- 0.4 eV; D[Cm-O] = 710 +/- 45 kJ mol (-1); D[Cm (+)-O] = 670 +/- 40 kJ mol (-1); and D[Cm (2+)-O] = 342 +/- 55 kJ mol (-1). Estimates for the M (2+)-O bond energies for M = Cm, La, Gd, and Lu are all intermediate between D[N 2-O] and D[OC-O] - that is, 167 kJ mol (-1) < D[M (2+)-O] < 532 kJ mol (-1) - such that the four MO (2+) ions fulfill the thermodynamic requirement for catalytic oxygen-atom transport from N2O to CO. It was demonstrated that the kinetics are also favorable and that the CmO (2+), LaO (2+), GdO (2+), and LuO (2+) dipositive ions each catalyze the gas-phase oxidation of CO to CO2 by N2O. The CmO 2 (+) ion appeared during the reaction of Cm (+) with O 2 when the intermediate, CmO (+), was not collisionally cooled - although its formation is kinetically and/or thermodynamically unfavorable, CmO 2 (+) is a stable species.     

土壤、沉积物系列标准物质中38种元素的ICP-MS定值

探讨了电感耦合等离子体质谱测定土壤元素的基体效应及元素间的基体干扰，采用模拟土壤元素天然组成比值的校正溶液，利用^115In-^103Rh双内标校正系统有效地抑制了分析信号的动态漂移，建立了测定土壤中元素的ICP－MS方法；对GBW07410－07416土壤、沉积物系列标准物质进行定值，测定结果与XRF分析结果比较，同时用于GBW07404、GBW07405、GBW07408、GBW07309管理样分析，结果令人满意。     

Gibbs energies of transfer of alkali metal cations between mutually saturated water-solvent systems determined from extraction experiments with radiotracer 137Cs

Thermodynamic standard Gibbs energies of transfer of alkali metal cations related to Cs+ cation [DeltatG degrees*,(Cs+)-[DeltatG degrees*,(M+)] between several mutually saturated solvents of the type water-solvent were calculated from determined extraction exchange constants Kexch degrees,*(Cs+/M+). The used liquid-liquid extraction method with radioactive tracing by 137Cs permits attaining higher precision of the values as compared to the methods used up to now. The data for o-nitrophenyloctyl ether, 1,2-dichloroethane, and 1-octanol were compared with literature sources and recommended absolute values of DeltatG degrees,*M+) are reported. For dissociating solvents, the dependences of [DeltatG degrees,*(Cs+) - [DeltatG degrees,*(M+)] on Gibbs energy of hydration of an ion, DeltaGhydr degrees are straight lines either for four cations Cs+, Rb+, K+, and Na+ (nitrosolvents) or for three cations Cs+, Rb+, and K+ (1,2-dichloroethane and 1-octanol). The hydration of Na+ and still more of Li+ in the water-saturated organic phase is apparent from the results. This manifests for high-water-content equilibrium 1-octanol even in a reversal of the values [i.e., DeltatG degrees*,(Li+) being more negative than DeltatG degrees,*(Na+)], although for Cs+, Rb+, and K+, the general trend is conserved. Water-saturated 1-octanol is thus slightly less basic than water, but the overall selectivity is very low. For one studied nondissociating solvent, dioctyl sebacate, the trend of the dependences of log Kexch degrees,*(CsB/M+) on DeltaGhydr degrees is similar to that of Kexch degrees,*(Cs+/M+) for polar solvents, but different for different anions B, thus reflecting ion association in the organic phase.     

Determination of U(IV) and U(VI) by ion chromatography-inductively coupled plasma mass spectrometry and its application to kinetic studies

The ions normally formed by actinides in aqueous solutions by the oxidation states III-VI are M3-, M4+, MO2+ and MO2(+2), respectively. Oxidation state representatives such as Am3+, Th4+, NpO+ and UO+, which resist oxidation state changes, were used to investigate a method to separate the oxidised species (MO2 and MO2(2+)) from the reduced species (M3+ and M4+). With this method the hexavalent state of uranium could be separated from the tetravalent state of uranium in aqueous media in less than 8 min. Uranium concentrations down to 10(-9) M could be analysed without changing the redox composition during the separation. The oxidation kinetics of the tetravalent uranium for different hydrochloric acid concentrations was investigated. The measurements showed good agreement with values found in the literature, although the uranium concentrations were one million times lower.     

Determination of rare earth elements in environmental matrices by sector-field inductively coupled plasma mass spectrometry

In the framework of an international certification campaign, sector-field inductively coupled plasma mass spectrometry (sector-field ICP-MS) was used for the accurate determination of the rare earth elements in five candidate reference materials: aquatic plant, calcareous soil, mussel tissue, river sediment, and tuna muscle. All samples were taken into solution by use of microwave-assisted or mixed microwave-assisted / open beaker acid digestion. Subsequently, the samples were appropriately diluted and subjected to ICP-MS analysis. Except for Sc, all the elements involved were determined at low mass resolution (R = 300). For Sc, application of a higher resolution setting (R = 3,000) was required to separate the analyte signal from those of several molecular ions which gave rise to spectral overlap at low mass resolution. Some of the heavier REE can also suffer from spectral overlap attributed to the occurrence of oxide ions (MO+) of the lighter REE and Ba. This spectral overlap could be successfully overcome by mathematical correction. Matrix effects were overcome by use of two carefully selected internal standards, such that external calibration could be used. On each occasion, a geological reference material was analyzed as a quality-control sample and the reliability of all results obtained was additionally checked by means of chondrite normalization. For tuna muscle the content of all REE was below the limit of detection. For calcareous soil and river sediment, low to sub microg g(-1) values were observed, whereas the REE content of aquatic plant and mussel tissue was considerably lower (low to sub ng g(-1)). Overall, the results obtained were in excellent agreement with the average values, calculated on the basis of all "accepted" values, obtained in different laboratories using different techniques.     

Determination of borate ion-pair stability constants by potentiometry and non-approximative linearization of titration data

Borate anions, B(OH)(-)(4), are known to associate with alkali and alkaline-earth metal cations in sea-water. The borate cation ion-pairs are of the general form MB(OH)((n-1)+)(4), where M(n+) is the cation. In this work, the cation borate stability constants (K*(MB)) have been evaluated for Na(+), Li(+), Mg(2+), Ca(2+) and Sr(2+) where K*(MB) = [MB(OH(4))((n-1)+)]/[M(n+)][B(OH)(-)(4)]. The K*(MB) values were obtained from values found for the stability constant of boric acid (K*(B)) in various electrolyte media at 25 degrees and an ionic strength of 0.7. Acid-base potentiometric titrations were performed in the electrolyte media with a standard Pt/H(2) electrode and a junctionless Ag/AgCl reference electrode to monitor the emf. A non-approximative equation was used to linearize the titration data. The values obtained were: K*(Lib) = 0.89 +/- 0.02, K*(NaB) = 0.44 +/- 0.01, K*(MgB) = 13.6 +/- 0.7, K*(CaB) = 11.4 +/- 0.15, K*(SrB) = 3.47 +/- 0.06. The values for K*(MB) correlate with the charge-density parameter z(2)/(r + 0.85), where r is the radius of the cation. The speciation of boron in sea-water was predicted from the K*(MB), data for the major cations present.     

模糊聚类-偏最小二乘回归光度法同时测定地质样品中金铂钯铑的研究

将模糊聚类分析与偏最小二乘法相结合,对地质样品中吸收光谱严重重叠的贵金属多组份体系进行解析,较好地解决了计算光度分析中校准模型的优化问题,使计算结果的精度得到了显著提高,分析结果的相对误差小于 10%,标准偏差小于 0.67,明显优于一般偏最小二乘 (PLS)法。采用小锍试金法消除样品中贱金属元素的干扰,其回收率为 92%～107%,标准偏差为 0.10～0.67;相对标准偏差为 4.7%～11.0%。并对影响聚类效果的参数选择作了讨论。     

Optical charge-transfer in iron(III)hexacyanoferrate(II): electro-intercalated cations induce lattice-energy-dependent ground-state energies

The maximum of the color-conferring charge-transfer (CT) band in Prussian Blue (PB) varies with the electrochemically introduced cation M(z+) incorporated (as "supernumerary") for charge neutrality, and the dependence on particular properties of the M(z+) has been sought. With alkali-metal ions, the CT-maximum shifts are in the same sequence as the PB mass changes on M+ insertion; the effect on the CT ground state of the intra-lattice interaction of an M+ with the ferrocyanide CN- moiety (competing with cation hydration), is then implicated in shifts of the maxima, as the ferrocyanide is the donor center in the optical CT. More definitely, for M2+ and Ag+, solubility-products of the insoluble M(z+) ferrocyanides (that provide direct indicators of the intra-lattice M(z+)-[Fe(II)(CN)(6)](4- interactions) show a strong correlation with the spectral shifts. The determining interaction of M(z+) with ferrocyanide within PB is enhanced in some cases by the accessibility of M(z+) oxidation states +/- 1 different from the common values. PB lattice energies and the ground states of the optical CTs thus appear closely interlinked. The electrochemical uptake of appreciable amounts of the M(z+) within the lattices was confirmed by XPS.