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1.
Franziska Nehring Dorrit E. Jacob Matthias G. Barth Stephen F. Foley 《Mikrochimica acta》2008,160(1-2):153-163
Trace element determination in rocks by fusion on an iridium strip heater followed by LA-ICP-MS analysis of the glass beads
is extended here to SiO2-rich rocks; rapid fusion of samples with >55 wt% SiO2 is facilitated by dilution by high purity MgO. The method developed here can rapidly and accurately determine numerous trace
elements in a large range of rock compositions in a short time (about 50 samples/day). Systematic evaluation for a large range
of rock compositions (natural rocks and reference materials AGV-2, GSP-2, JG-1a) with SiO2 contents between 45 and 80 wt% shows that reproducibility and accuracy within 10% can be routinely achieved for most of the
28 trace elements investigated (Rb, Sr, Cs, Ba, Ti, Zr, Hf, Nb, Ta, Sc, V, Cr, Ni, Pb, Th, U, REE). The 40 mg sample size
is smaller than for XRF, INAA or solution-ICP-MS, detection limits are lower, and trace element palettes more complete than
XRF and INAA. This microchemical method is thus attractive for the analysis of all natural geological materials as well as
for experimental applications with small samples. Samples with SiO2-contents >55 wt% require hot and long melting to achieve homogeneous glasses and eliminate all residual minerals, particularly
refractory accessory phases. Melting conditions of 1600 °C and 20 s for samples are recommended for SiO2 contents between 55 and 70 wt%, whereas 1800 °C and 20–30 s are often required for samples with >70 wt% SiO2. Problems are encountered for Pb and Cs due to volatilization on the Ir strip, for Sc due to interferences, and Zr and Hf
due to their sequestration in refractory accessory minerals.
Correspondence: Franziska Nehring, Department of Geosciences, University of Mainz, Becherweg 21, 55099 Mainz, Germany 相似文献
2.
V. K. Karandashev K. V. Zhernokleeva A. N. Turanov V. B. Baranovskaya Yu. A. Karpov 《Journal of Analytical Chemistry》2012,67(4):340-348
The study considers the possibility of using inductively coupled plasma mass spectrometry (ICP MS) for the determination of admixtures of Zr, Nb, Mo, Hf, Ta, W, and Te in rare-earth metals and their compounds using preliminary
extraction or extraction-chromatographic preconcentration. The admixture elements have been separated by extraction with trioctylphosphine
oxide in dichloroethane from hydrochloric acid media and back extraction with oxalic acid. Chemical separation provided a
1–4-order reduction of the lower quantification limit for these elements using ICP MS. 相似文献
3.
M. Miyoshi M. Shimono T. Hasenaka T. Sano T. Fukuoka 《Journal of Radioanalytical and Nuclear Chemistry》2008,278(2):343-347
Neutron induced prompt gamma-ray activation analysis (PGAA) is applied for determining boron contents in volcanic rocks, which
is an important element in the discussion of material circulation in volcanic arc systems. To evaluate the recycling of oceanic
crust in Kyushu, we analyzed boron and other trace element contents in basaltic rocks from the area. The basalts from volcanic
front have high B/Nb (2.9–3.7), B/Zr (0.1–0.2) and B/Sm (2.8–6.0) ratios, whereas those ratios in the basalts from backarc
are extremely low (<0.5; <0.1; 0.5–1.7), respectively. This indicates that the recycling of subducted oceanic crust to the
arc crust is limited in the volcanic front. 相似文献
4.
U. El-Ghawi N. Vajda Gy. Pátzay 《Journal of Radioanalytical and Nuclear Chemistry》1999,241(3):605-610
Samples of natural and fertilised soils were collected from Al-Gheran region, west of Tripoli, Libya. The samples were investigated
by means of INAA and ED-XRF for Al, Si, K, Ca, Sc, Cr, Mn, Fe, Co, Zn, Br, Rb, Sr, Y, Zr, Nb, Cs, Ba, Hf, Ta, Pb and Th. The
results indicate that the concentrations of K, Ca, Zn, Sr and Pb are 2–4 fold higher in fertilised compared to natural soil,
while the concentrations of Al, Si, Cr, Mn, Fe, Co, Rb, Y, Nb, Cs, Ba Ta and Th are nearly the same in all samples. Mn and
Fe values in two arable soils have been found to be 4–6 times lower than the average concentration in the earth's surface
soils. This study concludes that, although the levels of some trace elements important for human health are very low in both
natural and fertilised soils. Further research is needed to understand the full significance of the distribution transfer
and toxicity of trace elements introduced in imported fertilisers. 相似文献
5.
F. Monroy-Guzman D. Trubert L. Brillard J. B. Kim M. Hussonnois O. Constantinescu 《Journal of Radioanalytical and Nuclear Chemistry》1996,208(2):461-466
The behaviour of the elements Zr, Hf, Nb, Ta and Pa has been investigated on macroporous anion exchange resin BIORAD AGMP 1 in HF medium (from 0.02 to 2M). All the studied elements show strong adsorption properties at low HF concentration. The adsorption was found to be highly dependent on H+ and F– concentrations. The distribution of possible adsorbable complexes is discussed. 相似文献
6.
Hassan Karami Mir Fazlollah Mousavi Yadollah Yamini Mojtaba Shamsipur 《Mikrochimica acta》2006,154(3-4):221-228
A new simple flow injection analysis (FIA) system is described for on-line preconcentration by solid phase extraction and
simultaneous determination of Hf and Zr in different samples using inductively coupled plasma atomic emission spectroscopy
with a charge coupling detector (CCD). Quinalizarin (QA) was loaded on an octadecyl silica-polyethylene mini-column for the
retention of Hf and Zr ions in complexed form. A 0.3 M ammonium acetate was used as buffer for providing suitable conditions
for complexation and increasing reproducibility. Retained ions on the solid phase were then eluted by a solution containing
3.0 M HCl and 0.5 M HNO3. In this work, for reducing bandwidths of eluted ions, elution of minicolumn was carried out from opposite direction. The
same solution was used as both carrier and eluent, in order to increase the reproducibility. The eluted ions were introduced
into the conventional nebulizer of ICP–AES instrument. Effects of different parameters, including instrumental parameters
of ICP and FIA were optimized. An enrichment factor of 330 for each analyte ion was obtained at a concentration level of 80 ppb.
The detection limits of the proposed method for Hf and Zr were 0.16 ng mL−1 and 0.04 ng mL−1 respectively. The ability of the method for the recovery of Hf and Zr ions was tested in the presence of several diverse
metal ions in a synthetic mixture and some real matrices. It was also applied to the determination of Zr and Hf ions in a
standard soil and in a standard alloy as real samples. 相似文献
7.
Hafez S. Abdel Wahab J. Bérczi L. Bognár G. Keömley 《Journal of Radioanalytical and Nuclear Chemistry》1977,36(2):479-490
Twelve zircon samples representing different genetic types from Australia, China, Egypt, Hungary, Korea and Nigeria were examined
using the neutron activation techniques. The study of the trace elements encountered in zircons, especially Zr/Hf ratios,
shed the light on the type of zircon minerals as well as the mother rock from which zircons wrre separated. Furthermore, the
effect of the secondary processes on zircons and their host rocks were also studied. 相似文献
8.
N. S. Imyanitov 《Russian Journal of Inorganic Chemistry》2011,56(5):745-748
To illustrate the efficiency of a previously proposed new formulation of the Periodic Law, the proton affinities and gas-phase
basicities of 20 elements in the p- and d-blocks were predicted. These properties were considered as a function of the total number of p- or d-electrons in an atom, rather than depending on the nuclear charge or the number of outer-shell electrons. The analysis was
performed block by block separately. For p elements, the kainosymmetry and additional periodicity were taken into account. Equations were deduced and then used for
predicting the proton affinities and gas-phase basicities of p
4–p
6 elements (Se, Te, Po, At, and Rn) and d
2–d
10 elements (Zr, Nb, Mo, Tc, Ag, Cd, Hf, Ta, W, Re, Os, Ir, Pt, Au, and Hg). 相似文献
9.
F. I. Lobanov A. V. Stefanov I. M. Gibalo 《Journal of Radioanalytical and Nuclear Chemistry》1979,51(1):119-126
The melt extraction of Ti, Zr, Hf, Nb, Cr and Mo with β-diketones in naphthalene-biphenyl eutectics has been studied and the
temperature dependence of the equilibrium constants obtained. X-ray fluorescence determination of the elements in the solidified
organic extract is convenient. 相似文献
10.
Sw. Pajakoff 《Monatshefte für Chemie / Chemical Monthly》1969,100(1):280-289
Zusammenfassung Durch papierchromatographische Kristallisation ist es möglich, die Kristallisationsbedingungen für schwer kristallisierende Oxalatokomplexe des Al, Ga, In, Cr, Fe, Zr, Hf, Nb, Ta, Ti, Ge zu ermitteln und die kristallisationshemmenden Oxo- bzw. Hydroxokomplexformen quantitative zu eliminieren.Unter Ausnützung der verschieden großen Wanderungsgeschwindigkeit sowie dem unterschiedlichen Verhalten der Oxalate bzw. Oxalatokomplexe der Verunreinigungen und den dabei auftretenden Verteilungs-, Adsorptions-und Ionenaustauschvorgängen bei der papierchromatographischen Kristallisation kann diese zur Feinstreinigung einiger seltener Elemente wie z. B. Ge, Zr, Nb, Sc, U, In u. a. über Oxalate bzw. Oxalatokomplexe verwendet werden.Die Verteilung der Verunreinigungen während der papier-chromatographischen Kristallisation hat einen komplizierten Charakter und kann nicht durch Adsorption oder mechanische Einfügungen der Mutterlauge allein erklärt werden.
Mit 2 Abbildungen 相似文献
Paper chromatographic crystallization, a method for the preparation of complex compounds and for the purification of rare elements, I.
With the help of the paper chromatographic crystallization technique it is possible to determine optimum crystallization conditions of the badly crystallizing oxalato complexes of Al, Ga, In, Cr, Fe, Zr, Hf, Nb, Ta, Ti and Ge and to remove quantitatively their crystallization inhibiting oxo and hydroxo complexes, resp. The different migration rates and the behavior of the oxalates and oxalato complexes of the impurities as well as the distribution, adsorption and ion exchange phenomena operative in paper-chromatographic crystallization may be used for ultra-purification of some rare elements by means of their oxalates and oxalato complexes, for instance for Ge, Zr, Nb, Sc, U, In, and others. The distribution of impurities in paper chromatographic crystallization follows a complicated mechanism and is not explainable on the basis of adsorption or mechanical interaction of mother liquors alone.
Mit 2 Abbildungen 相似文献
11.
A group separation scheme has been developed for radiochemical neutron activation analysis for Ca, Cu, Zn, Ga, Rb, Sr, Zr, Sb, Cs, Ba, La, Nd, Sm, Eu, Gd, Tb, Ho, Tm, Yb, Lu, Hf, Ta, W and Th in a wide variety of silicate rocks and minerals, especially ultrabasic rocks and mafic minerals. The samples are decomposed in a hydrofluoric acid-nitric acid mixture in a PTFE-lined bomb. The soluble fluorides (Cu, Zn, Ga, Rb, Zr, Sb, Cs, Ht, Ta, W and Pa) are separated into three groups of elements by sequential elution from a cationexchange resin. The insoluble fluorides (Ca, Rb, Sr, Cs, Ba and REE) are dissolved and purified from interfering iron and scandium activities by extraction with tri-n-butyl phosphate. If necessary, the four main groups can be purified further from interfering activities such as 59Fe, 51Cr and 60Co. The accuracy and reproducibility of the procedure were tested by repeated analysis of U.S. Geological Survey standard granite G-2, andesite AGV-1 and dunite DTS-1. 相似文献
12.
R. Caletka R. Hausbeck V. Krivan 《Journal of Radioanalytical and Nuclear Chemistry》1990,142(2):383-391
Anion-exchange data have been obtained for the elements As, Hf, Mo, Nb, Pa, Re, Sb, Sn, Ta, Tc, W, and Zr in 0.1 to 10M H2SO4 and in HF–H2SO4 mixtures of combination extending from 0.1 to 10M HF and from 0.1 to 10M H2SO4. The distribution ratios for mixed solutions are presented in form of adsorption contour lines. 相似文献
13.
H. Bounouira A. Choukri R. Cherkaoui S. Chakiri M. Bounakhla K. Embarch 《Journal of Radioanalytical and Nuclear Chemistry》2012,292(3):1049-1058
The Bouregreg river basin is located in the Moroccan Central Massif which consists mainly of Palaeozoic formations that were
subject to the Hercynian orogeny. This study documents the background geochemistry and hydrochemistry of the Bouregreg river
basin, focusing on the distribution of major and trace elements. Rock samples were collected at nine locations along the Bouregreg
River and its tributaries in the winter of 2005. Major (Al, Fe, Mn, Na, K and Ti) and trace (Rb, Cs, Sr, Sc, Ba, Cr, V, Co,
Ni, Zn, As, Sb, La, Ce, Nd, Sm, Tb, Dy, Yb, Lu, Hf, Ta, Mo, Th and U) elements were analysed using instrumental neutron activation
analysis. Data show that most of the geochemistry and hydrochemistry are related to regional and local geology. The geochemical
heritage of geological environment in the Bouregreg river basin is very important, that results from the more compatible behaviour
and the inertia of some elements during the weathering (3d transition elements (Co, Ni, Cr,…), interne transition elements
f (lanthanides, Zr, Hf, Nb, Ta,…)). The geochemical homogeneity of the basin shows also heritage during the crustal accretion
(magmatism-metamorphism-sedimentation) and the typology of this continental area is the same that the upper continental crust.
Some anomalously high heavy metal analyses, particularly for As and Sb, may be related to anthropogenic activities. 相似文献
14.
The electronic structures of binary M21S8 (M = Nb, Zr) and isostructural ternary (M,M')21S8 (M, M' = Hf, Ti; Nb, Ta) phases have been studied by means of extended Hückel tight-binding band structure calculations. For the valence electron concentration in the binary group 5 metal phase Nb21S8, metal-metal bonding is optimized whereas, in the isostructural group 4 metal phase Zr21S8, metal-metal bonding levels exist above the Fermi level. However, the electronic structure analysis suggests a stable structure for M21S8 phases with group 4 metals and that (M,M')21S8 phases with mixed group 4 and group 5 metals, even if not yet reported, could well exist. In the ternary phase Nb6.9Ta14.1S8, a linear relationship exists between the magnitude of the metal-metal bonding capacity (as expressed by the total metal-metal Mulliken overlap population) of each crystallographically independent metal site and the occupation of the site with the heavier metal (i.e., the element with the greater bonding capability). The situation is quite more complex in Hf7.5Ti13.5S8, where the metal-metal bonding capacity of each site, differences in electronegativity between Ti and Hf, and site volume arguments must be taken into account to understand the metal site occupation. 相似文献
15.
The distribution of elements between polyether-type polyurethane foam, cyclic polyethers and hydrofluoric acid solution 总被引:1,自引:0,他引:1
The extraction of fifteen elements in the systems ?onsisting of polyurethane foam (polyether type)/HF-alkali-metal fluoride and cyclic polyether/HF-alkali-metal fluoride has been investigated. Little or no extraction was found for Co, Zn, Fe, Zr, Hf, Sn(IV), Nb, Pa, As(V), Mo, and W. Only Ta, Sb, Re, and Tc are well extracted with either polyurethane foam or dicyclohexano-18-crown-6 in dichloro-ethane under the conditions investigated. The mechanism of the extraction is discussed. The most interesting separation possibilities have been tested. 相似文献
16.
H. A. Das G. A. V. Gerritsen D. Hoede J. Zonderhuis 《Journal of Radioanalytical and Nuclear Chemistry》1973,14(2):415-426
This text describes the instrumental determination of some elements in silicate samples of ≃1 g by photon activation. The
following elements can be determined: In acidic rocks: Mg, Ca, Ti, Mn, Sr, Zr and Nb, in ultramafic rocks: Mg, Cr, Ni, and
Mn. The relative standard deviation is a few percent. 相似文献
17.
A turbidimetric method is described for the determination of tantalum with phenylarsonic acid. The method is fast and rarely requires preliminary separation. The only interfering elements are zirconium and niobium when present in molar ratios greater than Nb : Ta = 1 and Zr : Ta = 5. 相似文献
18.
Rapid sample digestion by fusion and chemical separation of Hf for isotopic analysis by MC-ICPMS 总被引:1,自引:0,他引:1
A new method for rapid sample digestion and efficient chemical separation of Hf and REE from rock samples for precise isotopic analysis is presented. Samples are digested by fusion in the presence of a lithium borate flux at 1100 °C and dissolved whilst molten in dilute nitric or hydrochloric acid. Prior to chemical separation using ion exchange techniques, Li and B from the flux material and Si from the sample are separated from the remaining major elements, REE and high field strength elements (HFSE) in the sample by Fe-hydroxide co-precipitation. The chemical separation of Hf is a two-stage procedure designed to first remove the remaining matrix elements (e.g. Fe, Ba) in the sample using standard cation exchange techniques, followed by separation of Hf from the REE and HFSE on TEVA extraction chromatographic resin. Hf yields are >90% and total procedural blanks are ca. 50 pg. Hf isotope ratios of a synthetic standard solution and replicate digestions of international rock standards BHVO-1 and BCR-1 measured on multi-collector inductively coupled plasma mass spectrometer (MC-ICPMS) reproduce similarly to ≤50 ppm (2 S.D.). The following elemental ratios are routinely obtained for elements, which interfere isobarically or may affect the ionisation and/or fractionation behaviour of Hf during analysis: 176Yb/176Hf<0.0001; 176Lu/176Hf<0.00001; Ti/Hf<0.05. This technique also provides a means of separating Nd from the REE fraction for isotopic analysis and, potentially, may be adapted for measurement of Lu/Hf ratios by isotope dilution techniques. 相似文献
19.
S. Ambe K. Yashiki H. Maeda S. Enomoto T. Ozaki F. Ambe 《Journal of Radioanalytical and Nuclear Chemistry》1998,236(1-2):181-185
Separation by means of supported liquid membranes is a useful method for the preparation and preconcentration of radioactive
nuclides. The permeation of rare earth elements through a bis(2-ethylhexyl) hydrogen phosphate-decalin membrane supported
on a microporous polytetrafluoroethylene sheet was studied using a multitracer containing radioactive nuclides of Sc, Zr,
Nb, Hf, Ce, Pm, Gd, Yb, and Lu. Permeation rates of these elements from feed solutions of various acidity to receiving solutions
of 0.5 mol·dm−3 HCl were determined simultaneously. The feed solution at pH 1.4 gave the highest permeation rate for Ce, Pm, and Gd, amounting
to about 95% of permeation for Ce and Pm, 80% for Gd, and 10% for Yb in 21 h. Scandium, Zr, Nb, Hf, and Lu were not transported
at all from the feed solution. Permeation rates of Yb and Lu from the feed solution at pH 1.4 to receiving solutions of 0.75,
1.0, 2.3, and 4.0 mol·dm−3 HCl increased with the concentration. The results obtained indicate that the light rare earth elements can be separated from
the heavy ones by this method. 相似文献
20.
ARelativisticDensityFunctionalStudyofEarlyTransitionMetalGroupⅢB-VBDimers ̄*LUXin,LIAOMeng-sheng ̄* ̄*,XUXin,WANGNan-qinandZHANG... 相似文献