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Saccharomyces cerevisiae MERIT.ferm was used as mono- and mixed-cultures with Williopsis saturnus var. mrakii NCYC500 in mango wine fermentation. A ratio of 1:1000 (Saccharomyces:Williopsis) was chosen for mixed-culture fermentation to enable longer persistence of the latter. The monoculture of S. cerevisiae and mixed-culture was able to ferment to dryness with 7.0% and 7.7% ethanol, respectively. The monoculture of W. mrakii produced 1.45% ethanol. The mango wines fermented by S. cerevisiae alone and the mixed-culture were more yeasty and winey, which reflected their higher amounts of fusel alcohols, ethyl esters and medium-chain fatty acids. The mango wine fermented by W. mrakii alone was much less alcoholic, but fruitier, sweeter, which corresponded to its higher levels of acetate esters.

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Journal of Radioanalytical and Nuclear Chemistry
Authors:
L. Zhou
,
S. Wen
,
J. Zhao
,
B. Yu
,
B. Han
, and
Ch. Yang

Abstract  

The -ray spectra of188Re decay have been studied by using two Ge/Li/ spectrometers and a three parameters /E-E-T/ List coincidence system. The energies and relative intensities of 52 -rays and cascade relations of 14 -rays are determined. Ten new -rays: 155 /633–478/, 984, 1096, 1463, 1332, 1530, 1574, 1810, 1867, and 1937 keV have been identified. The 155 /633–478/ transition is confirmed and its relative intensity is estimated by means of coincidence experiment. 24 levels of188Re are assigned. Among those, 6 levels are first put into the decay scheme of188Re. In addition to 1443 keV and 1937 keV levels, 1685, 1729 and 1965 keV levels are also observed in the decay of188Ir and other reaction studies. The 1948 level is recently suggested in the190Os/p, t/188Os reaction. The 486 keV and 811 keV -transitions are also put into the level scheme of188Re. The decay branching ratio is deduced.

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Journal of Radioanalytical and Nuclear Chemistry
Authors:
A. Krivokhatsky
,
Yu. Dubasov
,
E. Smirnova
,
N. Skovorodkin
,
V. Savonenkov
,
B. Alexandrov
, and
E. Lebedev

Abstract  

Actinide elements concentrations in the products of near release from CNPP accident were estimated. The data on uranium,237Np,241Am and plutonium and curium isotopes content in fuel particles are given. Sums of -emitting radionuclides and plutonium isotopes in reactor graphite particles and of uranium,242Cm,239+240Pu isotopes in the soil and aerosol samples were also determined. By 1989 soil and dust contamination in near release of the accident is due to long-lived -emitting plutonium isotopes.

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Journal of Radioanalytical and Nuclear Chemistry
Authors:
V. Frenkel
,
V. Chistyakov
,
Yu. Kulyako
,
E. Erin
,
I. Lebedev
,
G. Timofeev
, and
B. Myasoedov

Abstract  

During electrolysis of a248Cm/III/ solution in 2M K2CO3 at pH=13 partial oxidation of curium to a higher oxidation state, probably Cm/IV/, was observed. The absorption spectra of Cm/III/ and Cm/IV/ in K2CO3 solution were recorded and the molar extinction coefficients of main absorption bands of curium have been evaluated.

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Résumé  

On a déterminé la composition élémentaire d'échantillons de régolite lunaire obtenus par Luna 16 dans la mer d'abondance par méthode radioactive à l'aide d'un générateur de neutrons ainsi qu'un spectromètre γ à scintillations et détecteur Ge(Li).

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Journal of Radioanalytical and Nuclear Chemistry
Authors:
V. Frenkel
,
Yu. Kulyako
,
V. Chistyakov
,
I. Lebedev
,
B. Myasoedov
,
G. Timofeev
, and
E. Erin

Abstract  

The electrolysis of trivalent californium, terbium and praseodimium in 2M K2CO3 solutions at pH 13.2 results in a partial oxidation of the trivalent ions to a higher oxidation state. Absorption spectra of Cf/III/ in 1M HCLO4 and in 2M K2O3 and that of oxidized californium in carbonate solution have been recorded. Incomplete oxidation is accounted to a reducing species generated at high anode potentials.

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Abstract  

Information on the biokinetics of cerium can be obtained directly from humans by using stable isotopes as tracers. Neutron, photon and proton activation analysis have all been tested as analytical techniques able to quantify different isotopes of the same element in biological fluids. The experimental conditions were optimized for Ce analysis in blood plasma samples. The performances of the different techniques have been explored. The simultaneous determination of two Ce isotopes with the required sensitivity in the order of few ppb is difficult to obtain using a single technique, and, therefore, a combination of techniques can be envisaged.

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Abstract  

It has been shown that gamma-activation significantly extends possibilities of activation autoradiography with respect to determination of platinum group elements (PGE) in silicate samples. All PGE may be activated by bremsstrahlung with forming radionuclides having convenient half-lives for autoradiography (hours-days). Digital methods for quantitative 2D-densitometry of autoradiograph images by means of documents scanners have been developed and discussed. Approaches for increasing selectivity of analysis by means of autoradiography have been proposed and tested on the real sample containing PGE inclusions (analysis of decay kinetics while cooling, combination with gamma-ray spectrometry).

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Journal of Thermal Analysis and Calorimetry
Authors:
P. P. Fedorov
,
Yu. G. Sizganov
,
B. P. Sobolev
, and
M. Shvanner

A phase diagram of the system CaF2-GdF3 was studied by thermal and X-ray analysis. Two wide domains of solid solutions based on CaF2 and a high-temperature modification of α-GdF3 (LaF3-structural type) are present in this system. Two maxima were found on the melting curves of the Ca1−xGdxF2+x and α-(Gd1−yCayF3−y solid solutions, at 1428 ± 10‡ (5 mole % GdF3) and 1282 ± 5‡ (85 mole % GdF3), respectively. The coordinates of the eutectic are 60 mole % GdF3 and 1233 ± 5‡.

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Summary

Chestnut exhibits anti-inflammatory, styptic, anti-diarrhea, and analgestic effects as a traditional Chinese medicine. There is increasing evidence that shows that the consumption of chestnuts has become more important in human nutrition due to the health benefits provided by the antioxidants. The phenolic compounds are responsible for major bioactivities, such as anti-tumor and anti-oxidation. A high-performance liquid chromatography (HPLC) method with diode array detection (DAD) was established for the simultaneous determination of six phenolic compounds (gallic acid, GA; protocatechuic acid, PR; catechin, CA; epicatechin, EP; quercetin, QU; kaempferol, KA) in Chinese chestnut (Castanea mollissima blume) kernel. The sample followed by separation on Eclipse XDB-C18 column (150 × 4.6 mm, id., 5 μm) with gradient elution of methanol-1.0% acetate acid solution as a mobile phase, at a temperature of 30°C, under the ratio of 1.2 mL min−1, with 5 μL injection volume, and multi-wavelength synthesis was used with DAD. The correlation coefficients were larger than 0.999, the recoveries were 97.58% for GA, 100.41% for PA, 96.23% for CA, 101.38% for QU, 99.15% for EP, and 98.60% for KA, relative standard deviation (RSD) were 1.04% for GA, 1.21% for PA, 1.09% for CA, 1.19% for QU, 1.06% for EP, and 1.20% for KA. This method was applied for the determination of phenolics in chestnut kernel and was found to be fast, sensitive, and suitable.

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