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1.
R. H. Garstang 《Journal of research of the National Institute of Standards and Technology》1964,(1):61-73
This paper describes calculations of the transition probabilities of forbidden lines (magnetic dipole and electric quadrupole radiation) of laboratory and astrophysical interest. Results are given for Ti III, Cr II, Cr IV, Mn V, Mn VI, Fe VI, Fe VII, Ni I, Cu II, Ga I, Ge I, Ge II, As I, As III, Se I, Br I, Br II, Kr II, Kr III, Rb III, In I, Sn I, Sn II, Sb I, Sb III, Te I, I I, I II, Xe II, Xe III, Cs III, Hg II, Tl I, Pb I, Pb II, Bi I, Bi II, Bi III, Po I, and Rn II. 相似文献
2.
由于铂、钯材料被广泛应用于多种精密行业,其材料含量也越来越受到重视,目前采用的方法不是操作复杂就是范围太窄而不符合日常检测要求,因此急需建立一种简捷快速的、适用于铂、钯材料含量为95.0%-99.99%的化学分析方法。该文用电感耦合等离子发射光谱分析,测定铂、钯材料中铂(钯)、铑、铱、钌、金、银、铜、铁、镍、铝、铅、锰、铬、镁、锡、硅、锌及铋等杂质元素的方法,达到了检出限低、重复性好、回收率在88.3%-100%的检测目标。 相似文献
3.
An instrumental neutron activation method is developed to analyze chondritic metals and iron meteorites. By changing irradiation and decay times, and selecting suitable γ-ray and X-ray photopeaks, not only all platinum group elements (Ru, Rh, Pd, Os, Ir, Pt) but also other siderophilic elements (Fe, Co, Ni, Cu, Ga, Ge, As, Mo, Sb, W, Re, Au) can be nondestructively determined in the meteoritic metal samples. To obtain analytical data as accurate as possible, interfering reactions and neutron flux gradients during irradiation are considered. Siderophile elemental abundances measured for the Odessa iron meteorite are highly consistent with the literature values. Rh abundances for bulk H, L, LL, EH, and EL chondrites, which had been scarcely reported in the literature, are derived from Rh/Ni abundance ratios in the metal separates of the corresponding chondritic groups. 相似文献
4.
We propose a method for the analysis of solubility of metals in fusible melts and evaluate the solubility of Fe, Cr, Ni, Co, Ti, Nb, Mo, V, Cu, Pt, Au, Pd, and Ag in melts of Bi, Pb, Na, Al, and Sn in the approximation of ideal solutions. We also present thermodynamic parameters of dissolution of metals and demonstrate the possibility of using various metals for the application of coatings by the method of hot metallization.Karpenko Physicomechanical Institute, Ukrainian Academy of Sciences, L'viv. Translated from Fiziko-Khimicheskaya Mekhanika Materialov, Vol. 31, No. 4, pp. 76–84, July – August, 1995. 相似文献
5.
The determination of a wide spectrum of microelements in four oil samples from the Arlanskoye, Labaganskoye, Priobskoye, and Romashkinskoye oil fields of the Russian Federation by inductively coupled plasma mass spectrometry (ICP-MS) is described. The following two techniques have been used for the sample preparation: microwave decomposition of oil for determination of Be, Na, Mg, Al, S, Ca, Ti, V, Cr, Co, Ni, Cu, Zn, Ga, Se, Rb, Sr, Zr, Mo, Cs, Ba, W, Re, and U; and extraction concentrating with rotating helix columns (RHC) for determination of Nb, Ru, Rh, Ag, Cd, Sb, Te, Hf, Ir, Pt, Te, and rare earth elements. Concentrating of the oil microelements with RHC has been shown to result in significant improvement of the ICP-MS detection limits. 相似文献
6.
W. Knaepen C. Detavernier R.L. Van Meirhaeghe J. Jordan Sweet C. Lavoie 《Thin solid films》2008,516(15):4946-4952
By covering amorphous silicon (a-Si) with a thin metal film, it is possible to lower the crystallization temperature of the a-Si (typically around 800 °C when using ramp anneals) to levels which can be used in a manufacturing process. This phenomenon of Metal Induced Crystallization (MIC) has been reported previously for Ni, Au and Al. In this work, in-situ X-ray Diffraction was used to study the MIC process for 20 different metals (Ti, Zr, Hf, V, Nb, Ta, Cr, Mo, W, Mn, Re, Fe, Ru, Co, Rh, Ir, Ni, Pd, Pt, Cu, Ag, Au, Al). The 7 metals which lower the crystallization temperature the most are Ni, Pt, Pd, Cu, Au, Al and Ag. The crystallization kinetics were studied in detail for these 7 materials. In order to explain the MIC process, two models where used depending on the interaction of the metal with Si (eutectic or compound forming). 相似文献
7.
Amineboranes of the type L-BH3 (L = NH3; tert-BuNH2; Me2NH; Me3N) and sodium cyanotrihydroborate(III) (NaBH3CN) have been tested as derivatization reagents in the generation of volatile hydrides and elemental mercury following aqueous phase reaction with ionic species of Hg(II), As(III), As(V), Sb(V), Sb(III), Bi(III), Se(IV), Se(VI), Te(IV), and Te(VI). Continuous flow generation atomic absorption spectrometry coupled with a flameless quartz tube atomizer (T = 25 degrees C) and a miniature argon-hydrogen diffusion flame atomizer were employed for the detection of mercury vapors and volatile hydrides, respectively. All of the reductants were able to reduce Hg(II) to the elemental state, giving sensitivities comparable to NaBH4 reduction. Under reaction conditions giving maximum sensitivity for hydride generation with NaBH4, only some amineboranes are able to produce volatile hydrides from all the elements. No evidence of hydride formation was observed from the Se(VI) and Te(VI). In general, the reducing power decreased in the order NaBH4 > H3N-BH3 > tert-BuNH2-BH3 > NaBH3CN > or = Me2HN-BH3 > Me3N-BH3. In comparison with THB, amineboranes and NaBH3CN allowed, in general, a better control of interference effects of Fe(III), Ni(II), Co(II), and Cu(II). Application to determination of mercury in certified reference material is reported. The most likely mechanism of reaction of borane complexes in chemical vapor generation is based on the direct action of hydrogen bound to boron. 相似文献
8.
A new flame method of atomic absorption spectrometry is described. The liquid sample to be analyzed is transported as a high-speed liquid jet into a heated tube which is positioned in an air/acetylene flame. The jet is generated by means of an HPLC pump which feeds a smooth jet nozzle having a diameter of 50 microns or smaller. After traveling a distance of 10 cm, the liquid jet enters a small sample introduction hole, impacts onto the opposite inner wall of the tube furnace, and immediately vaporizes (jet impact vaporization, JIV). Both the complete introduction of the entire sample and the extended residence time inside the absorption volume result in an improvement in power of detection from 6- to 202-fold for 17 elements (Ag, As, Au, Bi, Cd, Cu, Hg, In, K, Pb, Pd, Rb, Sb, Se, Te, Tl, Zn). A standard deviation of 1.7-4.0% (n = 12, 50 microL) was achieved. Sample volumes between 10 microL and 1 mL have been investigated. For 50 microL sample volumes, the sampling frequency is 4/min. The new method can also be considered a simple, effective interface between HPLC and flame AAS. 相似文献
9.
《Materials Letters》2007,61(23-24):4573-4575
The optical radiation efficiencies, defined by the ratio of the scattering cross-section to the extinction cross-section, of spherical nanoparticles of 11 kinds of metal, Ag, Al, Au, Co, Cr, Cu, Ni, Pd, Pt, Sn and Ti, in the air were calculated based on the classical electromagnetic theory. This optical radiation efficiency represents the energy fraction of the incident light reradiated from the particle, not wasted as heat, and the obtained data is an effective guide for the selection of metal elements for nanoparticle-enhanced optoelectronic devices. Ag, Al, Au and Cu were found to have much higher optical radiation efficiencies than the other metals for most range of wavelengths. Strikingly, Ag and Al nanoparticles with diameters around 150 nm were found to exhibit over − 90% optical radiation efficiencies at most optical frequencies. 相似文献
10.
The technique of diffusive gradients in thin films (DGT) is a fairly new and useful tool for in situ measurements of labile metal ions in water. The applicability of DGTs was investigated by comparing independently determined or estimated diffusion coefficients with DGT effective diffusion coefficients (D(DGT)) for 55 elements. The DGTs were exposed at a controlled fluid velocity of 0.1 m s(-1) and a concentration of 1 ng mL(-1) at four pH levels between 4.7 and 6.0, and the D(DGT) values were determined from the uptake by the sampler. The measured D(DGT) values for the elements Co, Ni, Cu, Zn, Cd, Pb, Al, Mn, and Ga were close to previously published values with some deviations for Pb and Zn. The uptake of V, Cr, Fe, U, Mo, Ti, Ba, and Sr varied with pH, and there were some experimental problems that require further investigations. A novel set of D(DGT) values for the lanthanides (La, Ce, Pr, Nd, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm, Tb, Yb, Lu, Y) was established. The D(DGT) values for these were about 10-15% lower than for free ions in water and indicate that diffusion coefficients of metal ions in the agarose polyacrylamide diffusive hydrogel are 10-15% lower than in water. The high consistency of the data for the lanthanides establishes these elements as new performance test metals for the DGT sampler. The accumulation of the elements Li, Na, K, Rb, Mg, Ca, B, Tl, P, S, As, Bi, Se, Si, Sn, Sb, Te, Zr, Nb, Hf, Ta, W, Th, and Ag was low (D(DGT) lower than 10% of theoretical values). A more efficient elution procedure using concentrated nitric acid for the absorbent gel was established, with elution efficiencies between 95 and 100% for most metals. For deployment times of 24 h, detection limits from 0.001 to 1 ng mL(-1) were achieved with moderate precautions to prevent contamination. 相似文献
11.
Thermodynamics and phase diagrams of lead-free solder materials 总被引:1,自引:0,他引:1
H. Ipser H. Flandorfer Ch. Luef C. Schmetterer U. Saeed 《Journal of Materials Science: Materials in Electronics》2007,18(1-3):3-17
Many of the existing and most promising lead-free solders for electronics contain tin or tin and indium as a low melting base alloy with small additions of silver and/or copper. Layers of nickel or palladium are frequently used contact materials. This makes the two quaternary systems Ag–Cu–Ni–Sn and Ag–In–Pd–Sn of considerable importance for the understanding of the processes that occur during soldering and during operation of the soldered devices. The present review gives a brief survey on experimental thermodynamic and phase diagram research in our laboratory. Thermodynamic data were obtained by calorimetric measurements, whereas phase equilibria were determined by X-ray diffraction, thermal analyses and metallographic methods (optical and electron microscopy). Enthalpies of mixing for liquid alloys are reported for the binary systems Ag–Sn, Cu–Sn, Ni–Sn, In–Sn, Pd–Sn, and Ag–Ni, the ternary systems Ag–Cu–Sn, Cu–Ni–Sn, Ag–Ni–Sn, Ag–Pd–Sn, In–Pd–Sn, and Ag–In–Sn, and the two quaternary systems themselves, i.e. Ag–Cu–Ni–Sn, and Ag–In–Pd–Sn. Enthalpies of formation are given for solid intermetallic compounds in the three systems Ag–Sn, Cu–Sn, and Ni–Sn. Phase equilibria are presented for binary Ni–Sn and ternary Ag–Ni–Sn, Ag–In–Pd and In–Pd–Sn. In addition, enthalpies of mixing of liquid alloys are also reported for the two ternary systems Bi–Cu–Sn and Bi–Sn–Zn which are of interest for Bi–Sn and Sn–Zn solders. 相似文献
12.
Application of surface-enhanced infrared absorption spectroscopy to investigate pyridine adsorption on platinum-group electrodes 总被引:1,自引:0,他引:1
In situ surface-enhanced infrared absorption spectroscopy (SEIRAS) was applied to investigate adsorption configurations of pyridine (Py) on platinum, palladium, ruthenium, and rhodium nanoparticle film electrodes. The results reveal that alpha-pyridyl species predominantly form on Pt electrodes by assuming an edge-on configuration with its ring N and alpha-C atoms bonding to the Pt surface, while on Ru and Rh electrodes pyridine molecules essentially remain intact by adopting a slightly edge-tilted configuration through bonding with its N lone pair electrons. Py adsorption on a Pd electrode may lie in between the above two cases; both alpha-pyridyl species and edge-tilted intact pyridine could be significantly present. Further comparison of the typical adsorption configurations on the above four electrodes with those on Ag, Au, Cu, Cd, and Ni film electrodes suggests that valence electrons and the periodic row of metals may play an important role in determining the adsorption configuration. 相似文献
13.
Long-term leaching from MSWI air-pollution-control residues: leaching characterization and modeling 总被引:2,自引:0,他引:2
Long-term leaching of Ca, Fe, Mg, K, Na, S, Al, As, Ba, Cd, Co, Cr, Cu, Hg, Mn, Ni, Pb, Zn, Mo, Sb, Si, Sn, Sr, Ti, V, P, Cl, and dissolved organic carbon from two different municipal solid waste incineration (MSWI) air-pollution-control residues was monitored during 24 months of column percolation experiments; liquid-to-solid (L/S) ratios of 200-250L/kg corresponding to more than 10,000 years in a conventional landfill were reached. Less than 2% of the initially present As, Cu, Pb, Zn, Cr, and Sb had leached during the course of the experiments. Concentrations of Cd, Fe, Mg, Hg, Mn, Ni, Co, Sn, Ti, and P were generally bellow 1microg/L; overall less than 1% of their mass leached. Column leaching data were further used in a two-step geochemical modeling in PHREEQC in order to (i) identify solubility controlling minerals and (ii) evaluate their interactions in a water-percolated column system over L/S of 250L/kg. Adequate predictions of pH, alkalinity, and the leaching of Ca, S, Al, Si, Ba, and Zn were obtained in a simultaneous calculation. Also, it was suggested that removal of Ca and S together with depletion of several minerals apparently caused dissolution of ettringite-like phases. In turn, significant increase in leaching of oxyanions (especially Sb and Cr) was observed at late stage of leaching experiments. 相似文献
14.
Eutectic alloys of Sn with Cu, Cd, Al, Pb and Sb (peritectic) were produced by the melt-spinning technique. These alloying elements were chosen according to their valencies +1, +2, +3, +4 and +5 respectively. X-ray diffraction analysis (XRD) was carried out. Young’s modulus and resistivity were measured. It was found that, alloying Sn with low valency metals such as Cu and Cd increases the axial ratio and alloying Sn with high valency metals such as Pb, Sb and Bi decreases the axial ratio. Also Young’s modulus was found to increase by increasing the axial ratio and decreases by decreasing it. On the contrary the resistivity decreases by increasing the axial ratio. 相似文献
15.
Celebić A Baucić M Stipetić J Baucić I Miko S Momcilović B 《Journal of materials science. Materials in medicine》2006,17(4):301-305
Objectives: The release of metal ions (Al, Ag, Au, Ca, Cd, Co, Cr, Cu, Mg, Mo, Ni, Pd, Pt, Ti, and Zn) from the commercial gold/platinum
(Au/Pt) dental alloy of declared composition was studied.
Methods: Au/Pt was soaked in pH 6.0 phosphate buffer, 3.5 pH phosphate buffer and pH 3.5 mixture of lactic, formic and acetic acid,
and incubated at 37 °C for 1, 2, 3, 4, 5, 6, 7, 14, 21, and 30 days. Six samples (n = 6) of every solution were prepared for
any time period. Inductively coupled plasma atomic emission spectroscopy was used for analysis of the released elements.
Results: Results demonstrated release of only Cr, Cu, Fe, and Zn from the tested Au/Pt dental alloy (ANOVA, p < 0.001 for buffer,
time, and interaction, respectively); however, only Cu and Zn were declared.
Conclusions: The undeclared chromium from Au/Pt dental alloy, or some other element might be responsible for the contact allergy thus
far attributed to the gold. 相似文献
16.
Partitioning behavior of trace elements during pilot-scale fluidized bed combustion of high ash content lignite 总被引:1,自引:0,他引:1
This study describes the partitioning of 20 trace elements (As, B, Ba, Cd, Co, Cr, Cu, Hg, Li, Mn, Mo, Ni, P, Pb, Sb, Se, Sn, Tl, V, Zn) and eight major and minor elements (Al, Ca, Fe, K, Mg, Na, Si, Ti) during the combustion of high ash content lignite. The experiments were carried out in the 0.3 MW(t) Middle East Technical University (METU) atmospheric bubbling fluidized bed combustor (ABFBC) test rig with and without limestone addition. Inert bed material utilized in the experiments was bed ash obtained previously from the combustion of the same lignite without limestone addition in the same test rig. Concentrations of trace elements in coal, limestone, bottom ash, cyclone ash and filter ash were determined by inductively coupled plasma optical emission spectroscopy (ICP-OES). Partitioning of major and minor elements are influenced by the ash split between the bottom ash and fly ash and that the major proportion of most of the trace elements (As, Ba, Cr, Hg, Li, Mo, Ni, Sn, V, Zn) are recovered in fly ash. Limestone addition shifts the partitioning of Ba, Cr, Mo, Ni, Sn, V, Zn from bottom ash to fly ash. 相似文献
17.
The thermodynamic activities in the silicon binary melts with Al, Ca, Mg, Fe, Ti, Zn, Cu, Ag, Au, Sn, Pb, Bi, Sb, Ga, In,
Pt, Ni, Mn and Rh are studied. The silicon activities along the liquidus are calculated through a quasi-regular solution model
using the recently determined liquidus constants for the silicon binary systems. The silicon activities at its melting point
are calculated considering regular solution approximation. The activities of the other melt component at the silicon melting
point are also calculated through the graphical integration of the Gibbs–Duhem equation for the activity coefficient, which
are further utilized to determine the corresponding activities along the liquidus. The calculated activities are presented
graphically, and it is indicated that the results are consistent with the reported activity data in the literature. The activities
in the dilute solutions are also calculated graphically. Moreover, the activities of particular dilute solute elements in
silicon are calculated through a simple formula, which is a function of the liquidus constants. 相似文献
18.
Review Room-temperature reactions in thin metal couples 总被引:1,自引:0,他引:1
Results of a 40 year-long investigation of room-temperature formation of compounds in 144 thin-film couples obtained by combining 23 metals (Ag, Al, Au, Bi, Cd, Co, Cr, Cu, Ga, Ge, In, Mg, Mn, Ni, Pb, Pd, Pt, Sb, Sm, Sn, Te, Ti, Zn) are presented. The data from published papers of the present and other authors have been complemented by unpublished data of the present authors. The systematized results and their analysis point to the following. In 39 couples, a total of 65 compounds are formed. The reactions of compound formation last from 1 min to 10 y, depending on the specimen type and procedure of film deposition. In the bulk–film specimens, the number of compounds formed is smaller and the reaction is slower than in the film–film specimens prepared by thermal evaporation. In the specimens with the sputtered top layer, a greater number of compounds is formed and the compound formation reaction proceeds more rapidly than in the couples prepared by thermal evaporation of both metals. The compounds formed can be transformed into others containing higher percentage of one of the constituents, until the specimen contains an excess of that constituent, provided that such compounds exist in the respective phase diagram. At the beginning of the reaction, compounds are formed in a broad concentration range, while at the reaction end the range is narrowed down, becoming close to that in the corresponding phase diagram. The optimum conditions for compound formation exist in the couples consisting of a high-melting metal and a low-melting one, provided that the potential compound is not high-melting. If the potential compound is high-melting, or if both metals in the couple have melting points in the same temperature range, no compound formation takes place at room temperature. In the couples consisting of a given high-melting metal and one of the low-melting metals, a linear relationship exists between the interdiffusion coefficient and the melting point of the low-melting metal. If, for a couple consisting of a high-melting metal and a low-melting one, there is a solid solubility range of the low-melting metal, during the course of long ageing, the compound formed is decomposed and the low-melting metal is amorphized. During the long ageing, the ambient atmosphere acts on the metal films (alone or in a couple) leading to formation of oxides, hydroxides or carbonates. The results obtained complement the low-temperature range results in the respective phase diagrams. 相似文献
19.
This study describes the partitioning of 18 trace elements (As, Ba, Cd, Co, Cr, Cu, Li, Mn, Mo, Ni, P, Pb, Sb, Se, Sn, Tl, V, Zn) and 9 major and minor elements (Al, Ca, Fe, K, Mg, Na, S, Si, Ti) during co-firing of olive residue, hazelnut shell and cotton residue with high sulfur and ash content lignite in 0.3 MW(t) Middle East Technical University (METU) Atmospheric Bubbling Fluidized Bed Combustor (ABFBC) test rig with limestone addition. Concentrations of trace elements in coal, biomass, limestone, bottom ash, cyclone ash and filter ash were determined by inductively coupled plasma optical emission and mass spectroscopy (ICP-OES and ICP-MS). Partitioning of major and minor elements are influenced by the ash split between the bottom ash and fly ash and that the major proportion of most of the trace elements (As, Ba, Co, Cr, Cu, Li, Mn, Mo, Ni, Pb, Tl, V and Zn) are recovered in fly ash when firing lignite only. Co-firing lignite with biomass enhances partitioning of these elements to fly ash. Co-firing also shifts the partitioning of Cd, P, Sb and Sn from bottom to fly ash. 相似文献
20.
Determination of heavy metals by ICP-OES and F-AAS after preconcentration with 2,2'-bipyridyl and erythrosine 总被引:2,自引:1,他引:1
The applicability of 2,2'-bipyridyl and erythrosine co-precipitation method for the separation and preconcentration of some heavy metals, such as Cd, Co, Cu, Ni, Pb and Zn in actual samples for their determination by ICP-OES and F-AAS was studied. Experimental conditions influencing the recovery of the investigated metals, such as pH, molar ratio of 2,2'-bipyridyl to erythrosine, the effect of time on co-precipitation were optimized. The analytical characteristics of the method (e.g. limit of detection, sensitivity, linear range and preconcentration factor) were obtained. The limits of detection LOD (ng mL(-1)) of the ICP-OES (F-AAS) method were: Cd: 4.0 (7.75), Co: 3.1 (57.2), Cu: 18 (10.3), Ni 21.3 (32.8), Pb: 35.9 (29.2) and Zn: 10.2 (6.90). The recovery of all the elements tested was more than 93%. The influence of inorganic matrix was examined. The proposed method was applied to determination of Cd, Co, Cu, Ni, Pb and Zn in vegetables and certified reference material (NCS ZC85006 Tomato). 相似文献