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D. W. Golightly

Publications and source records attributed to D. W. Golightly.

10 recordsLinked to original sources
USGS2002

Analytical performance of a low-gas-flow torch optimized for inductively coupled plasma atomic emission spectrometry

An inductively coupled Ar plasma (ICP), generated in a lowflow torch, was investigated by the simplex optimization technique for simultaneous, multielement, atomic emission spectrometry (AES). The variables studied included forward power, observation height, gas flow (outer, intermediate, and nebulizer carrier) and sample uptake rate. When the ICP was operated at 720-W forward power with a total gas flow of 5 L/min, the signal-to-background ratios (S/B) of spectral lines from 20 elements were either comparable or inferior, by a factor ranging from 1.5 to 2, to the results obtained from a conventional Ar ICP. Matrix effect studies on the Ca-PO4 system revealed that the plasma generated in the low-flow torch was as free of vaporizatton-atomizatton interferences as the conventional ICP, but easily ionizable elements produced a greater level of suppression or enhancement effects which could be reduced at higher forward powers. Electron number densities, as determined via the series until line merging technique, were tower ht the plasma sustained in the low-flow torch as compared with the conventional ICP. ?? 1984 American Chemical Society.

Analytical Chemistry↗
USGS1991

Methods for the separation of rhenium, osmium and molybdenum applicable to isotope geochemistry

Effective methods are described for the chemical separation of rhenium, osmium and molybdenum. The methods are based on distillation and anion-exchange chromatography, and have been the basis for rhenium—osmium isotope studies of ore deposits and meteorites. Successful anion-exchange separation of osmium requires both recognition and careful control of the osmium species in solution; thus, distillation of osmium tetroxide from a mixture of sulfuric acid and hydrogen peroxide is preferred to anion-exchange. Distribution coefficients measured for perrhenate in sulfuric acid media are sufficiently high ( K d > 500) for rhenium to be directly loaded onto an ion-exchange column from a distillation residue and subsequently eluted with nitric acid. Polymerization of molybdenum species during elution is prevented by use of a solution that is 1 M in hydrochloric acid and 1 M in sodium chloride.

Talanta↗
USGS1989

Spark ablation-inductively coupled plasma spectrometry for analysis of geologic materials

Spark ablation—inductively coupled plasma (SA-ICP) spectrometry is applied to the measurement of hafnium—zirconium ratios in zircons and to the determination of cerium, cobalt, iron, lead, nickel and phosphorus in ferromanganese nodules. Six operating parameters used for the high-voltage spark and argon-ICP combination are established by sequential simplex optimization of both signal-to-background ratio and signal-to-noise ratio. The time-dependences of the atomic emission signals of analytes and matrix elements ablated from a finely pulverized sample embedded in a pressed disk of copper demonstrate selective sampling by the spark. Concentration ratios of hafnium to zirconium in zircons are measured with a precision of 4% (relative standard deviation, RSD). For ferromanganese nodules, spectral measurements based on intensity ratios of analyte line to the Mn(II) 257.610 nm line provide precisions of analysis in the range from 7 to 14% RSD. The accuracy of analysis depends on use of standard additions of the reference material USGS Nod P-1, and an independent measurement of the Mn concentration.

Talanta↗
USGS1980

Chemical analysis of 659 coal samples from the eastern United States

This report includes the analytical data on 659 coal samples from 8 States east of the Mississippi River. The number of samples from each State are: Pennsylvania, 132; Ohio, 101; Maryland, 25; West Virginia, 254; Virginia, 33; Indiana, 49; Massachusetts, 5; and Rhode Island, 10. The analytic data are filed in the National Coal Resource Data System of the U.S. Geological Survey. The U.S. Geological Survey has quantitatively determined 35 major, minor, and trace elements in each sample. Tests were also made for 35 other trace elements using semi-quantitative spectrographic methods. In addition, the Coal Analysis Section of the U.S. Department of Energy has determined proximate and ultimate analyses, 3cu, forms of sulfur, free-swelling indexes, and ash-fusion temperatures on 563 of the 659 samples. Comparison of the geometric means of the 644 bituminous coal samples of this report with an additional 968 bituminous coal samples of the eastern United States reported by Swanson and others in 1976 and by Zubovic and others in 1979 is shown in tables 2a-c. As shown by the means for ultimate and proximate analyses, small differences exist between the two sets of data; however, only the moisture and oxygen contents are significantly different. The forms of sulfur, ash-fusion temperature and heat of combustion are similar. The means for the major and minor oxides in ash are similar for SiO 2 , K 2 O, Fe 2 O 3 , TiO 2 , MgO, and P 2 O 5 are lower, whereas, MnO is higher in the analyses of the samples of this report. Eighteen of the means for the trace elements in the coal are about equal for the two sets of samples. Only As, Co, La, Li, and Pb are significantly higher, whereas, Ag, B, Ba, Be, Cd, Cs, F, Ge, Mo, Nb, and Nd are lower in the in the 64L,bituminous coal samples of this report.

Indiana, Maryland, Massachusetts, Ohio, Pennsylvan↗
USGS1977

Sets of spectral lines for spectrographic thermometry and manometry in d.c. arcs of geologic materials

Sets of 5 Fe(I) lines and 3 Ti(I) Ti(II) line pairs have been characterized for precise spectrographic thermometry and manometry, respectively, in d.c. arcs of geologic materials. The recommended lines are free of spectral interferences, exhibit minimal self absorption within defined concentration intervals, and are useful for chemically-unaltered silicate rocks, arced in an argon—oxygen stream. The functional character of these lines in thermometry and manometry of d.c. arcs for evaluations of electrical parameter effects, for temporal studies, and for matrix-effect investigations on real samples is illustrated.

Spectrochimica Acta Part B: Atomic Spectroscopy↗