Showing papers on "Arsenic published in 1976"
147 citations
TL;DR: A dissolution technique has been developed for herbage and the method applied to the analysis of water and orchard leaves and maintenance of the pH between 4 and 5 permits the selective determination of arsenic(III) in mixtures of arsenic (III) with arsenic(V).
Abstract: In the atomic-absorption determination of arsenic by the hydride evolution method with sodium borohydride, maintenance of the pH between 4 and 5 permits the selective determination of arsenic(III) in mixtures of arsenic(III) with arsenic(V). Total arsenic can be determined separately by evolution from 5 M hydrochloric acid. A dissolution technique has been developed for herbage and the method applied to the analysis of water and orchard leaves.
146 citations
TL;DR: In this article, a scheme of analysis for the determination of arsenic, antimony, bismuth, lead, selenium, tellurium and tin in steel by evolution of their volatile hydrides and subsequent atomic absorption spectrometry in an argon-hydrogen-entrained air flame was presented.
130 citations
TL;DR: The results of initial epidemiological studies suggest that the human cancer mortality is lower in areas providing an adequate dietary intake of selenium as estimated from the seenium content in grains and forage crops in various regions of the United States, or the dietary selenum intakes as calculated from food consumption data in various countries.
106 citations
TL;DR: In this paper, channeling effect measurements using MeV 4He ions were used in the study of the anneal of implantation disorder in Si The Si was implanted at LN2 temperature with arsenic or boron to dose le
Abstract: Channeling effect measurements using MeV 4He ions were used in the study of the anneal of implantation disorder in Si The Si was implanted at LN2 temperature with arsenic or boron to dose le
92 citations
TL;DR: A chronology of key events: (8) Paciga, J. J., Chattopadhyay, A., Jervis, R. E., in “Nuclear Methods in Environmental .Research-11”, J R. Vogt and W. Meyer, Eds.
Abstract: 6,441-48 (1972). (9) Paciga, J. J., Chattopadhyay, A., Jervis, R. E., in “Nuclear Methods in Environmental .Research-11”, J. R. Vogt and W. Meyer, Eds., pp 286-300, University of Missouri, Columbia, Mo., 1974. (10) Hoffman, G. L., Duce, R. A,, Enuiron. Sci. Technol., 5 , 1134 (1971). (11) Gordon, G. E., Zoller, W. H., Gladney, E. S., in “Trace Substances in Environmental Health-VII”, D. D. Hemphill, Ed., pp 167-75, University of Missouri, Columbia, Mo., 1973. (12) John, W., Kaifer, R., Rahn, K., Wesolowski, J . J., Atmos. Enuiron., 7, 107-18 (1973). (13) Pattenden, N. J., presented a t the 41st Ann. Conf. of the National Society for Clean Air, 14-18 October, Cardiff, UK, 1974. (14) Bogen, J., Atmos. Enuiron., 7,1117-25 (1973). (16) Wedepohl, K. H., in “Origin and Distribution of the Elements”, L. H. Ahrens, Ed., pp 999-1016, Pergamon Press, Oxford, England, 1968. (16) Lee, R. E., Jr., Goranson, S., Emiron. Sci. Technol., 6,1019-24
71 citations
TL;DR: In this paper, a method for the analysis of selenium and rsenic in surface water specimens by atomic absorption spectroscopy is described, which employs sodium borohydride for conversion of SE and arsenic compounds in specimens to hydrogen selenide and arsine.
Abstract: fully automated method for the analysis of selenium and rsenic in surface water specimens by atomic absorption spectroscopy is described. The technique employs sodium borohydride for conversion of selenium and arsenic compounds in specimens to hydrogen selenide and arsine. To increase the efficiency of hydride recovery for analysis, the reacted specimen is stripped using a heated column. The hydride gas and hydrogen evolved from the chemical reaction is then combusted in a tube furnace placed in the optical path of an atomic absorption spectrophotometer. Seventy specimens can be analyzed per hour with a detection limit of 0.019 μg/liter for selenium and 0.011 μg/liter for arsenic.
63 citations
63 citations
TL;DR: It was determined that arsenic in seafood can alter, in a dramatic fashion, the urinary arsenic values determined for smelter workers within 24 hours following consumption, and it is recommended that the absorption of arsenic trioxide due to industrial exposure is best evaluated from urine samples collected at least two days after seafood has been eaten.
Abstract: 1. A study of 24 smelter workers routinely exposed to arsenic trioxide was conducted to evaluate some characteristics of its absorption and excretion. A statistically significant correlation was found between airborne arsenic trioxide concentrations below 300 mug/m3 and urinary arsenic values below 500 mug/liter. These men wore personal monitors for five consecutive work days and were determined to have been exposed to average airborne arsenic concentrations of 53 mug/m3 (70 mug/m3 of arsenic trioxide) which increased their urinary arsenic values from 152 mug/liter to 200 mug/liter (an average gain on 32%). 2. The background average urinary arsenic value for adult males not exposed to arsenic trioxide in industry was determined to be 52.6 mug/liter for 204 men during preemployment examinations. 3. After removal from industrial arsenic trioxide exposure, the rate of fall in urinary arsenic values varies with the magnitude of the urinary arsenic level. An initial decrease of 9.5% per day was measured for workers having urinary arsenic values below 200 mug/liter. The initial decrease is about 21% per day for workers with urinary arsenic values over 600 mug/liter. 4. It was determined that arsenic in seafood can alter, in a dramatic fashion, the urinary arsenic values determined for smelter workers within 24 hours following consumption. It is recommended, therefore, that the absorption of arsenic trioxide due to industrial exposure is best evaluated from urine samples collected at least two days after seafood has been eaten.
62 citations
TL;DR: Secondary ion mass spectrometry has been used for depth profiling of arsenic and phosphorus in silicon as discussed by the authors, and high sensitivity analysis down to concentrations of a few 1017 atoms/cm2 could be achieved by energy discrimination against mass interfering molecular secondary ions.
Abstract: Secondary ion mass spectrometry has been used for depth profiling of arsenic and phosphorus in silicon. High‐sensitivity analysis down to concentrations of a few 1017 atoms/cm2 could be achieved by energy discrimination against mass interfering molecular secondary ions.
59 citations
TL;DR: In this article, photolysis of toluene solutions of dialkyl-phosphorus or -arsenic chlorides (Me3Si)2CH]2MCl (M = P or As) or bisamido phosphorus (BPH) or -arsenic-centred radicals (me3Si2N]2N], characterized by their e.r.s. spectra.
Abstract: Photolysis of toluene solutions of dialkyl-phosphorus or -arsenic chlorides [(Me3Si)2CH]2MCl (M = P or As) or bisamido-phosphorus or -arsenic chlorides [(Me3Si)2N]2MCl (M = P or As) in the presence of an electron-rich olefin leads to solutions containing persistent (t½ > 1 month at 20 °C) two-co-ordinate phosphorus or arsenic-centred radicals [(Me3Si)2CH]2M· or [(Me3Si)2N]2M·(M = P or As) characterised by their e.s.r. spectra.
TL;DR: The proposed methods are applied satisfactorily for determination of As(III) and As(V) in various types of water.
Journal Article•
TL;DR: The unique capabilities of the proton microprobe in an atmospheric environment as a biological tool are illustrated in studies of arsenic and mercury distributions in siingle strands of hair from poisoning victims and of the distributions of several abundant elements in frozen hydrated eye and kidney specimens from rats.
Abstract: The unique capabilities of the proton microprobe in an atmospheric environment as a biological tool are illustrated in studies of arsenic and mercury distributions in siingle strands of hair from poisoning victims and of the distributions of several abundant elements in frozen hydrated eye and kidney specimens from rats.
TL;DR: Gaseous evolution of As from a soil treated with arsenic-74 labeled disodium methanearsonate (DSMAAs) at 100 μg/g was a function of organic matter addition and moisture conditions as mentioned in this paper.
Abstract: Gaseous evolution of As from a soil treated with arsenic-74 labeled disodium methanearsonate (DSMAAs) at 100 μg/g was a function of organic matter addition and moisture conditions. Loss of As was greatest from soils that received an exogenous carbon source and were maintained under wet conditions. Arsenic-74 sorbed by soils of pH 4, 6, and 8 was fractionated by a differential dissolution procedure commonly used for phosphorus. Iron arsenate (soluble in 0.1N NaOH) was the most abundant form followed by aluminum arsenate (soluble in 0.5N NH4F). The soils generally contained more aluminum arsenate at pH 4 than at pH 6 or 8. Calcium arsenate fractions (soluble in 0.5N H2SO4) were usually higher at pH 6 and 8 than at pH 4. Water-soluble forms and nonextractable forms were inversely proportional to each other. Additional Index Words: aresenic residues, arsine, methanearsonate. View complete article To view this complete article, insert Disc 3 then click button8
TL;DR: In this paper, the effect of the segragation of tin, antimony, phosphorus and arsenic to the prior austenite grain boundaries on the susceptibility of an AISI 3340 steel to liquid metal induced embrittlement by lead and tin is studied.
TL;DR: An arsine generation-atomic absorption method for the rapid and precise determination of 004-4000 ppm arsenic in geological materials is described in this paper, where a siliceous sample is decomposed with perchloric, nitric and hydrofluoric acids and potassium permanganate solution, and the residue is dissolved in dilute hydrochloric acid.
Patent•
25 Jun 1976
TL;DR: In this article, a process for removing arsenic from a mineral oil feedstock containing at least 2 ppmw arsenic is described, where the feedstock is contacted with a catalytic absorbent comprising a nickel sulfide and a molybdenum sulfide composited with a refractory oxide, each being present in relatively large proportions.
Abstract: A process for removing arsenic from a mineral oil feedstock containing at least 2 ppmw arsenic comprises contacting said feedstock at elevated temperatures with a catalytic absorbent comprising a nickel sulfide and a molybdenum sulfide composited with a refractory oxide, said nickel sulfide and said refractory oxide each being present in relatively large proportions. Under preferred conditions a product oil stream containing less than 2 ppmw arsenic is continuously obtained from said contacting until a weight of arsenic at least equivalent to that of the nickel in the catalytic absorbent has been absorbed thereon.
TL;DR: In this paper, an atomic-absorption spectrophotometric method for the rapid and sensitive determination of arsenic, antimony, and selenium with the hydride-argon/hydrogen flame system has been studied.
Abstract: An atomic-absorption spectrophotometric method for the rapid and sensitive determination of arsenic, antimony, and selenium with the hydride-argon/hydrogen flame system has been studied. The comparison of the zinc tablet combined with stannous chloride and potassium iodide, and the sodium borohydride tablet reduction systems are described. The sensitivities and precisions of both reduction systems are estimated to be nearly the same. From the results of the comprehensive study on interferences, the zinc system is concluded to be more selective than the sodium borohydride system, which is especially true for arsenic.
IBM1
TL;DR: In this article, a detailed account of the transformation of small interstitial loops into large shear loops is given, which depend on the initial implantation conditions and are obtained after implantation through thin SiO2 layers.
Abstract: Arsenic implantation into Si and annealing at 800°C creates a high density of small interstitial dislocation loops. Further annealing in the range of 900°C to 1000°C causes coarser dislocation structures which depend on the initial implantation conditions. After implantation through thin SiO2 layers large winding dislocation loops of shear type are obtained. A detailed account is given of the transformation of small interstitial loops into large shear loops.
Wenn man Arsen in Silizium implantiert und bei 800°C tempert, entsteht eine hohe Dichte kleiner interstitieller Versetzungsschleifen. Weiteres Tempern bei 900 bis 1000°C fuhrt zu groberen Versetzungsstrukturen, deren Art von den anfanglichen Implantationsbedingungen abhangt. Nach Implantation durch dunne SiO2-Schichten hindurch entstehen grose kletternde Versetzungsschleifen vom Scherungstyp. Es wird eine ausfuhrliche Betrachtung zur Umwandlung der kleinen interstitiellen Schleifen in grose Scherungsschleifen durchgefuhrt.
TL;DR: In this article, the authors reproduce qualitative differences between crystalline and amorphous arsenic in spectroscopic data and reproduce chemical pseudopotential calculations of, and a local environment approach to, the density of states of arsenic in the A7 structure and in a three-fold coordinated random network.
TL;DR: Arsenic concentrations in zooplankton and fish muscle were relatively low compared with the shrimp species; amphipods contained more arsenic than copepods or euphausiids, and American plaice more than redfish, turbot, and Atlantic cod.
Abstract: Inorganic arsenic concentrations in sea water and mud, and total arsenic concentrations in bodies of shrimp, zooplankton, and fish from northern Newfoundland and southern Labrador were measured. Th...
TL;DR: Arsenic(V) can be determined separately from total inorganic arsenic after extracting arsenic(III) as its pyrrolidine dithiocarbamate into chloroform by a molybdenum blue method.
TL;DR: In this article, selective adsorption of trace arsenite and arsenate anions in an aqueous solution by ferric hydroxyde supported on silica gel particles was investigated.
Abstract: Selective adsorption of trace arsenite- and arsenate anions in an aqueous solution by ferric hydroxyde supported on silica gel particles was investigated. Silica gel particles were loaded with ferric hydroxide of the range of 1 – 3 wt. % in terms of Fe based on the dry gel, and the extent of adsorption of arsenite or arsenate ion measured by batch- and column processes, being the highest at pH 6 in the presence of diverse foreign ions. With the use of silica gel containing 3.3 wt. % Fe, as much as 0.07 m mol of arsenic per gram of dry gel was adsorbed.
TL;DR: A semi-automated method for the determination of arsenic in soil and vegetation is described, using an atomic absorption spectrometer equipped with an arsenic hollow-cathode lamp to record atomic absorption at 193.7 nm.
TL;DR: In this paper, the average values of Cd, Hg, Pb, and As in soils are 5.9, 0.36, 104, and 4.4 ppm, respectively, and those in barley plants are 1.65,0.10, 1.20, and 0.12 ppm.
Abstract: Analysis of zinc-polluted soils and the barley plants grown in these soils shows a relatively higher concentration of Cd, Hg, Pb, and As. The average values of Cd, Hg, Pb, and As in soils are 5.9, 0.36, 104, and 4.4 ppm, respectively, and those in barley plants are 1.65, 0.10, 1.20, and 0.12 ppm, respectively. The levels of Se, Cr, and V are, however, in the normal concentration range. Applied zinc has no real effect on the content and uptake of the trace elements concerned in barley. The results indicate that contamination of soils with Cd, Hg, Pb, and possibly As has occurred, and is presently occurring, in this area.
TL;DR: The high and variable arsenic accumulation before mortality of fish exposed to 500 and 1000 ppM arsenic seems to indicate that mortality might be caused by a second mechanism (perhaps mucous-clogging of the gills due to metallic irritation) at these levels.
Abstract: The purpose of the study was to determine to what extent green sunfish, an active freshwater fish, was affected by short-term exposures to high concentrations of a less potent arsenical, sodium arsenate. Acute or short-term effects of this arsenical were assessed on the basis of mortality; lethal time for 50 percent mortality (LT/sub 50/) and lethal dosage for 50 percent mortality (LD/sub 50/) were calculated by straight line graphic interpolation. Arsenic accumulation in whole fish at the time of death was measured using neutron activation analysis (NAA) and these values were compared with arsenic exposure, time before mortality, and fish condition. Cumulative percent mortality for all fish in the triplicate experiment increased with increasing exposure concentrations. Lethal times for 50 percent mortality for 100, 500, and 1000 ppM arsenic were 46, 17, and 12 hr, respectively. This effect was also observed at lower exposure levels: at 30 and 60 ppM arsenic and 20/sup 0/C, LT/sub 50/ decreased from 527 to 210 hr for green sunfish (SORENSEN 1974). Other metals produced the same effects. Time of death was compared to total arsenic accumulation. Fish exposed 10 100 ppM arsenic appear to be more successful in removing arsenic from the body overmore » short periods of time. Arsenic retention in organs of L cyanellus appeared to be short in duration. The high and variable arsenic accumulation before mortality of fish exposed to 500 and 1000 ppM arsenic seems to indicate that mortality might be caused by a second mechanism (perhaps mucous-clogging of the gills due to metallic irritation) at these levels. A lack of a correlation between various specimen parameters and fish weight might be due, in part, to the fact that nonessential elements such as arsenic (LIEBSCHER and SMITH 1968) are merely contaminations of tissue and have no significant function.« less