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Abstract  

Indium(III) in small doses stimulates the metabolism of human beings. Its compounds are regarded toxic as it damages the heart, kidney and liver and it may also be teratogenic. As an established infection-imaging modality, nuclear medicine plays a vital health-care role in the diagnosis and subsequent effective treatment of this condition. Several techniques in nuclear medicine significantly aid infection diagnosis, including imaging with 99mTc-hexamethylpropyleneamine oxime, 99mTc-stannous fluoride colloid labeled leukocytes, 67Ga-citrate and 111In-oxine. In the present investigation a rapid and selective method for the extraction of In(III) using 114mIn as a tracer has been developed. The extractant, quinaldic acid has been used for the extraction of In(III) from alkaline medium into isoamyl alcohol. The extractability of In(III) was studied as a function of pH, equilibration period, effect of diluents and diverse ions. The substoichiometric method of extraction for determining the composition of the complex has also been established. The extracted In(III) from the organic phase could be stripped into the aqueous phase using 3N hydrochloric acid. The results obtained were reproducible.

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The performance of a semisynthetic bisexual lure (SBL, containing isoamyl alcohol, acetic acid and red wine) previously found attractive for a number of noctuids was compared with that of the respective synthetic sex attractants of Orthosia cerasi (=stabilis), O. cruda, O. gothica, O. incerta, Anorthoa munda and Conistra vaccini. The respective sex attractants performed significantly better in the Orthosia spp. than the SBL lure, which, although regularly catching low numbers of both females and males, did not differ significantly from zero catch in unbaited control traps. On the other hand, the SBL lure performed as well as the sex attractant in C. vaccini. Sizeable catches of C. rubiginea, C. rubiginosa and C. erythrocephala were also recorded in traps with the SBL lure. The SBL lure can prove to be a useful tool in ecological and faunistical studies of Conistra and related hibernating Xylenini species.

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Journal of Thermal Analysis and Calorimetry
Authors: K. Sreekanth, M. Kondaiah, D. Sravana Kumar and D. Krishna Rao

molecular interactions in the mixtures containing commercially important alcohols like isopropyl/isobutyl/isoamyl alcohols and ethanol that are mixed in equimolar ratio. Further such equimolar mixtures of ethanol + isopropyl alcohol/isobutyl alcohol/isoamyl

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Abstract  

A substoichiometric radiochemical extraction method has been developed for the determination of cerium employing a chelating agent -hydroxy-naphthaldoxime, dissolved in isoamyl alcohol. The reagent was synthesised and characterised in our laboratory. The method developed was utilized to determine the cerium content of some natural samples.

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Abstract  

A radiochemical displacement method has been developed for the determination of 10 g amounts of iron and antimony. The effect of pH and various foreign ions on the displacement of tracer60Co from labeled Co-o-Hydroxybenzaldehyde isonicotinoyl hydrazone (BIH) complex in isoamyl alcohol by iron and antimony was studied.

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Abstract  

54Mn is analyzed in complex food ash of high cationic environment. The initial step is an extraction atpH 2.7 with hexane containing di(2-ethylhexyl) phosphoric acid (HDEHP) to complex the54Mn and other nuclides. The manganese is reextracted into an alkaline EDTA buffer which is washed with 1% 8-hydroxyquinoline in chloroform containing 5% isoamyl alcohol. The54Mn is determined by gamma spectrometry with recoveries ranging from 96.6 to 99.4%.

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Abstract  

The solvent extraction of Tc(IV) and Tc(VII) by isoamyl alcohol has been studied. The TcCl 6 2− and TcO 4 ions are both extracted from 3M H2SO4 solution but hydrolyzed Tc(IV) species are not. This permits the separation of the two valence states of technetium. The air oxidation of carrier-free hydrolyzed99mTc(IV) may be limited by the presence of99Tc carrier in the same chemical form. Paper chromatography and electrophoresis were used to identify TcCl 6 2− , TcO 4 and hydrolyzed species. It was also found that the hydrolyzed ReCl 6 2− can reduce TcO 4 to Tc(IV).

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Present study demonstrated the isolation of most promising β-galactosidase producing bacterial strain SB from soil. Morphological, biochemical, and 16s rRNA sequence analysis identified the bacterial strain as Arthrobacter oxydans. Several chemicals, including SDS, Triton X-100, Tween 20, isoamyl alcohol, and toluene-acetone mixture, were applied for extraction of intracellular β-galactosidase from the bacterial strain Arthrobacter oxydans. Among these, Tween 20 was recorded to be most effective. Role of pH, temperature, and shaker speed on production of β-galactosidase was evaluated using Box-Behnken design of response surface methodology. According to Box-Behnken analysis, optimum production of β-galactosidase (21.38 U (mg–1 protein)) is predicted at pH 6.76, temperature 36.1 °C, and shaker speed 121.37 r.p.m. The parameters are validated with the nearest value.

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Abstract  

The equilibrium extraction behavior of Sm(III), Eu(III) and Dy(III) from aqueous NaClO4 solutions in the pH range of 4–9 at 0.1 M ionic strength into organic solutions of 1-nitroso-2-naphthol (HA) and 1,10-phenanthroline (Phen) has been studied. The equilibrium concentrations of Eu were assayed through the 344 keV photopeak of the152Eu radiotracer used. The concentrations of Sm and Dy were measured by irradiating one mL portions of the organic extract and analyzing the 104 and 108 keV photopeaks of the short-lived neutron activation products,155Sm and165mDy, respectively. Quantitative extraction of Eu with 5×10–2 M HA alone was obtained in the pH range of 6.7–7.8 with n-butanol, 7.4–8.5 with chloroform, 8.0–8.7 with ethyl acetate, 7.7–8.5 with isoamyl alcohol and 6.1–8.0 with methyl isobutyl ketone (MIBK). But, Eu was extracted only to a maximum of 78% and 83% in the pH range of 8.3–8.9 and 7.4–8.1 with carbon tetrachloride and xylene, respectively. The extraction of Sm and Dy were found quantitative in the pH range of 6.3–7.0 and 6.6–7.1, respectively, with 5×10–2 M HA alone in MIBK solutions. The synergistic extraction of Eu was quantitative in the pH range of 6.6–9.8 with chloroform, 7.8–8.9 with ethyl acetate, 7.7–8.5 with isoamyl alcohol and 6.0–9.6 with MIBK when 1×10–2 M each of HA and Phen were employed. Sm and Dy were quantitatively extracted into MIBK solutions containing 5×10–2 M each of HA and Phen in the pH range 6.0–7.5 and 6.1–7.5, respectively. The distribution ratios of these lanthanides (Ln) were determined as a function of pH, and HA and Phen concentrations. The analysis of the data suggests that these Ln are extracted as LnA3 chelates when HA alone is used. In the presence of HA and Phen, both LnA3(Phen) and LnA3(Phen)2 adducts are formed only in the MIBK system while LnA3(Phen) complexes are the predominant ones in all other solvent systems studied. The extraction constants and the adduct formation constants of these complexes have been calculated.

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Three yeasts from the genus Williopsis (W. saturnus var. mrakii NCYC500, W. saturnus var. saturnus CBS254 and W. californica NCYC2590) were examined for their ability to ferment longan juice and to enhance formation of longan wine aroma compounds. The three yeasts showed similar growth kinetics and pH changes during fermentation. W. californica was the least sugar consumer. Many of the naturally occurring volatiles (ethyl esters, fatty acids, aldehydes, and terpenes) in the juice were partially or completely degraded. The three yeasts varied with their ability to produce and utilise volatiles. Esters were the major volatiles produced with some esters being catabolised while other esters remained stable. The amount of most alcohols increased while of aldehydes decreased. W. saturnus CBS254 was the best producer of ethyl acetate, isobutyl acetate, isoamyl acetate and 2-phenethyl acetate, whereas W. californica NCYC2590 was the highest producer of butyl acetate. Ethanol was produced in similar amounts by W. mrakii and W. saturnus but at a minimal level by W. californica. W. mrakii formed the highest amount of isobutyl alcohol, isoamyl alcohol and 2-phenylethyl alcohol. Although the amounts of most of the major volatiles at the end of fermentation (day 14) differed statistically among the yeasts, it remained to be seen whether the quantitative differences can be detected organoleptically. These fi ndings suggest that yeasts from the genus Williopsis could be exploited for longan wine aroma enhancement either singly or in co-inoculation with Saccharomyces.

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