Abundance Of Zinc Research Articles

Geochemistry of the Cretaceous Shales and Its Implication on Regional Tectonics and Correlation: Wyoming and Montana

The Cretaceous strata of north-central Wyoming and south-central Montana consist of shale, mudstone, and sandstone with minor conglomerate, coal, and bentonite. The primary objective in this paper is to utilize the mineralogical and geochemical data of the critical and dominant lithofacies group comprised of shale and mudstone to reevaluate regional tectonics, provenance aspects, and correlation of the Cretaceous foreland basin sediments. Relative abundances of nickel, zinc, lanthanum, and cerium in the marine samples can be attributed largely to the organic-rich nature and presence of mineral phase apatite in the marine group. The abundance of these trace elements is presumably related to the proximity of local bedrock source region and distinctive clay mineral suite in the marine sediments. Low concentrations of zirconium, titanium, and chromium in nonmarine Cloverly mudrock indicate an alkaline to peralkaline original sediment (ash) composition as opposed to trachytic to dacitic component for the marine group. Furthermore, the marine sequences in the Cretaceous foreland basin are related to thrust load-induced flexure. Overall geochemical behavior of the analyzed samples seems to be related more to confidently to tectonism rather than different provenance. This geochemical classification can be utilized for stratigraphic correlation of the several lenticular sandstone members encased withinmore » the various Cretaceous units and offers an excellent opportunity for future oil and gas exploration in this region.« less

The abundance of zinc in Hg-Mn stars

view Abstract Citations (19) References (30) Co-Reads Similar Papers Volume Content Graphics Metrics Export Citation NASA/ADS The Abundance of Zinc in Hg-Mn Stars Sadakane, Kozo ; Jugaku, Jun ; Takada-Hidai, Masahide Abstract The resonance line of singly ionized zinc (Zn II) at 2062.00 A is quantitatively analyzed, and the abundances of Zn in atmospheres of early-type stars have been determined for the first time. The line is analyzed in IUE spectra of six reference (normal) stars between spectral types B5 and A0 and of 23 Hg-Mn stars. The abundances of Zn in the reference stars coincide with the solar value within + or - 0.5 dex. Zn is overabundant in five Hg-Mn stars, while it is underabundant by at least 1.0 dex in 12 of them. The Hg-Mn stars Phi Her and Mu Lep show the strongest and the weakest Zn II lines, respectively, and the abundance of Zn in Phi Her is at least 100,000 times higher than that in Mu Lep. No clear dependence of the Zn abundance on the effective temperature is found. There also is no clear correlation between the degree of abundance anomaly of Zn and those of the two neighboring elements Cu and Ga. A definite nonsolar abundance pattern, excesses of both Cu and Ga over Zn, is found for six Hg-Mn stars. Publication: The Astrophysical Journal Pub Date: February 1988 DOI: 10.1086/166048 Bibcode: 1988ApJ...325..776S Keywords: Abundance; Manganese; Mercury (Metal); Metallic Stars; Stellar Spectra; Zinc; A Stars; Early Stars; Iue; Peculiar Stars; Resonance Lines; Stellar Atmospheres; Astrophysics; STARS: ABUNDANCES; STARS: PECULIAR A; ULTRAVIOLET: SPECTRA full text sources ADS | data products SIMBAD (29) MAST (1) INES (1)

Effects of alcohol ingestion on zinc content of human and rat central nervous systems

The abundance of zinc in hippocampal mossy fibers has stimulated investigation of zinc status in various pathologic states in which behavioral or anatomic deficits involving the hippocampus are known to occur. Limited autopsy studies of chronic alcoholic humans have suggested that the content of zinc might be reduced in several brain regions whereas reported attempts to replicate these findings in ethanol-exposed experimental animals have produced inconsistent results. In this comparative study, the zinc concentration in 10 brain regions, all spinal cord segments, and microdissected hippocampal subfields was measured by isotope ratio mass spectrometry. A widespread 15 to 20% reduction in zinc content was observed in all regions of chronic alcoholics compared with controls but a selective involvement of hippocampus was not detected. In the experimental studies, groups of rats were exposed to ethanol by one of three routes: inhalation for 2 weeks, as an ethanol/liquid diet for 3 months, or a single intoxicating i.p. dose. Determinations of tissue uptake of radiozinc and of total zinc content were made. In contrast to human pathologic material, zinc pool size and tissue uptakes were not affected by experimental ethanol administration by any route. This study confirmed that a reduction in zinc concentration occurs in the central nervous system of chronic alcoholics. The animal studies indicated, however, that simple ethanol exposure, even for prolonged periods, does not perturb zinc metabolism in brain. Together, these observations argue that the abnormalities of zinc metabolism in chronic alcoholics are possibly secondary to homeostatic alterations associated with hepatic failure.

The gaseous component of the disk around Beta Pictoris

Optical spectra of alpha Lyr, alpha PsA, and beta Pic have been obtained at a velocity resolution of 3 km/s. No circumstellar absorption lines of Ca II or Na I are detected toward alpha Lyr or alpha PsA at sensitive limits. In the favorable case of beta Pic, where the circumstellar disk imaged by Smith and Terrile (1984) is seen nearly edge-on, a strong, narrow, circumstellar Ca II K absorption line previously reported by Slettebak (1982) and weaker, still narrower circumstellar Na I D lines are detected. Negative results of high sensitivity also are obtained for the Ca I 4226 A and CH(+) 4232 A lines, along with upper limits on the Zn II 2026, 2062 A doublet from archival IUE spectra. Under assumptions which agree with other well-established observations of the gaseous abundances of calcium and zinc, the total gaseous column density of hydrogen along a radius of the circumstellar disk is between 10 to the 18th and 4 x 10 to the 20th/sq cm. Within the boundaries of the dust disk detected by Smith and Terrile (1984) the total gaseous mass then is less than about 2, or less than 1 percent of the mass of the planetary system. A simplified model of the density distribution in the gaseous disk yields a characteristic total density n(H) of about 100,000/cu cm, which exceeds that of all interplanetary gas at earth's position by a factor of about 10,000.

The abundance of Zinc in the cosmic radiation

ABSTRACT Lexan polycarbonate track detector arrays flown from Sioux Falls at an atmospheric depth of ≃ 3.8 g/cm 2 and designed originally for ultra heavy cosmic ray composition studies have been analysed in order to determine the Zn/Ni ratio in the cosmic radiation. Fast scanning procedures which were designed to extract the transcobalt nuclei and discriminate against the overwhelming background of iron events yielded approximately 400 nuclei in the region 28 ≤ Z ≤ 36. The Zn/Ni ratio, based on ten Zn nuclei was found to be (2.4 ± 0.8) × 10 −2 .

Dispersal of heavy metals from abandoned mine workings and their transference through terrestrial food chains

Past exploitation of metalliferous ores has resulted in extensive metal contamination of surface soils in the vicinity of a derelict mine complex. Soil lead and zinc concentrations were found to decrease exponentially with distance downwind of abandoned metalliferous spoil heaps. Dispersal of metal-rich waste materials is attributed mainly to wind erosion, percolating waters and surface drainage waters. The abundance of lead and zinc in surface soils close to spoil heaps largely reflects the chemical composition of the waste material. However, heavy metal ratios in native fauna were inconsistent with those of the indigenous soil and vegetation, reflecting differences in the relative mobilities of metallic pollutants. Examinations of carnivores, herbivores and their estimated diets indicated that cadmium has a greater potential for accumulation through lower terrestrial trophic levels than both lead and zinc. The low transfer potential of zinc may be associated with its essential role in biological systems. The high mobility of cadmium may result from its accumulation in soft tissues rather than skeletal components, the latter constituting the principal sites for deposition of lead.

The abundance of cadmium and zinc in meteorites

A stable isotope dilution technique using solid source mass spectrometry has been used to accurately determine Cd and Zn in a wide range of materials. The abundance of Cd has been determined in 19 iron, 28 stone and 1 stony-iron meteorites, together with a number of other samples. The abundance of Zn has also been determined for most of these samples. This has enabled the relationship between Cd and Zn to be examined in iron and stone meteorites. The abundance pattern of Zn in iron meteorites supports the existence of chemical groups.

A survey of the isotopic and elemental abundance of zinc

A mass spectrometric technique applicable to the study of high ionization potential elements has been used to investigate the possibility of natural processes producing variations in the isotopic composition of zinc. No significant variations were detected in the samples studied. The isotopic abundances of the mass 64, 66, 67, 68 and 70 isotopes in terrestrial zinc are estimated to be 48.6 ± 0.1, 27.90 ± 0.08, 4.10 ± 0.03, 18.8 ± 0.2 and 0.62 ± 0.01 per cent respectively. Zinc concentrations have been determined in 14 stone, 1 stony-iron and 20 iron meteorites and in a large number of terrestrial samples using isotope dilution and atomic absorption methods. The range of concentrations found in stone meteorites and terrestrial rocks is similar to that previously reported, but for the iron meteorites a slightly wider concentration range has been observed (0.026–90 ppm).

The abundances of selenium, tellurium, silver, palladium, cadmium, and zinc in chondritic meteorites

The abundances of the elements Se, Te, Ag, Pd, Cd, and Zn have been determined in a number of carbonaceous, enstatite, and ordinary chondrites by a neutron activation technique. Of these, only palladium is essentially unfractionated among the various chrondrite groups; the fractionation of the other elements is generally consistent with the model proposed by Anders (1964) .

L. Greenland and Gordon G. Goles (1965) Copper and zinc abundances in chondritic meteorites Geochim. Cosmochim. Acta29, 1285–1292

L. Greenland and Gordon G. Goles (1965) Copper and zinc abundances in chondritic meteorites Geochim. Cosmochim. Acta29, 1285–1292

On the Photographic Ion Quantity Measurment in the Spark Source Mass Spectrometry

The correct emulsion characteristic curve was constructed by plotting isotopic abundance against Seidel function obtained from the isotopic lines of Sn+;spectra taken on a single plate at three different exposures, (Fig. 1). The monitor current during the exposure was always kept below 1×10-13A which had been found necessary in our laboratory to avoid the broading of spectral lines, a condition essential to construct a correct characteristic curve. It is to be noted in this connection that a certain microphotometer gave a false result that the line width at half intensity decreased with density though in fact it remained constant. Employing the characteristic curve thus obtained, constancy of ion quantity and exactness isotopic abundance measurement were examined by the use of a number of zinc or carbon spectra taken all over a single Ilford Q 2 plate both by changing magnetic filed strength and by vertically displacing the plate, (Fig. 1). All these spectra were taken at constant exposure by keeping the monitor current below 1×10-13A. Results. The ion quantities* obtained of zinc and carbon isotopes were found constant within ±5 percent. The isotopic abundance of zinc was exact within ±2 percent absolute. *Here ion quantity means a quantity proportional to the number of ions that have arrived at the line position.

Abundances of Copper, Zinc, and Lead in Some Sulfide Deposits

An initial study has been made on the abundance and mutual behavior of copper, zinc, and lead in a certain type of sulfide concentration. Fourteen sample deposits, some from each of Australia, Canada, and Eire, have been found to show, in addition to similarities in environment and mineralogy, several chemical affinities. Among these are a persistently low copper content, a poor correlation between copper and zinc, on the one hand, and quite a good correlation between lead and zinc, on the other; a similarity of mean lead: zinc ratios throughout the group; and, lastly, a marked consistency, throughout the group of deposits, in the behavior of the ternary group copper-zinc-lead. Although no definite conclusions concerning genesis are drawn, the possible significances of some of the compositional features are discussed. In addition, the mutual behavior of the copper, zinc, and lead in the deposits is compared with that noted by E. B. Sandell and S. S. Goldich in some North American igneous rocks The mutual behavior of the three metals is remarkably similar in both classes of material.