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Abstract  

The extraction behavior of uranium, thorium and nitric acid has been investigated for the TEHDGA/isodecyl alcohol/n-dodecane solvent system. Conditional acid uptake constant (K H) of TEHDGA/n-dodecane and the ratio of TEHDGA to nitric acid were obtained as 1.72 and 1:0.96, respectively. The extracted species of uranium and thorium in the organic phase were found to be UO2(NO3)2·2TEHDGA and Th(NO3)4·2TEHDGA. A workable separation factor (D Th/D U) of the order of 300 was observed between thorium and uranium in the nitric acid range of 0.5M to 1.5M. Similar separation factor was also achieved at higher acidity when thorium was present in large concentration compared to uranium. These results indicate that TEHDGA solvent system could be a potential candidate for separation of thorium from uranium.

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Journal of Radioanalytical and Nuclear Chemistry
Authors: Y. Gautam, A. Sharma, S. Sharma, K. Rao, J. Kumar, V. Kumar, B. Singh, A. Kumar, and A. Hedge

Abstract  

Atmospheric tritium activity is measured regularly around Narora Atomic Power Station (NAPS) since gaseous waste, which contains tritium, is being released through a 145 m high stack at NAPS site. Atmospheric data collected during 2004–2008 shows a large variation of 3H concentration in air, fluctuating in the range of ≤0.2–91.6 Bq m−3. Significantly, higher tritium levels were measured in samples near the site boundary (1.6 km) of NAPS compared to off-site locations. The atmospheric dilution factor was found to be in the range of 1.1 × 10−7–7.3 × 10−7 s m−3. The scavenging ratio of NAPS site was found to be varying from 0.2 × 104 to 14.1 × 104 (Bq m−3 rain water per Bq m−3 air). The inhalation dose to a member of general public at different distances (1.6–30 km) from NAPS site was found to be ranged from 0.08–0.21 μSv year−1.

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Acta Chromatographica
Authors: S.M. Nurulain, S. Ojha, S. Dhanasekaran, K. Kuča, N. Nalin, C. Sharma, A. Adem, and H. Kalász

Distribution of K027, a hydrophilic, positively charged compound is monitored in the body of pregnant mice using high-performance liquid chromatography (HPLC). Intraperitoneal injection was done on the 18th day of pregnancy; the plasma and brains of the mother mice, placentae and the fetuses’ brains were dissected following 5, 15, 30, 60, and 120 min of treatment. Significant incorporation of K027 was found in the placentae and in fetuses’ brains relative to its levels in the mothers’ plasma and brains. This incorporation warns of a possible adjustment of dose of pyridinium aldoxime antidotes in case of pregnancy. Further studies with different gestational periods and animal models are warranted.

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Chromium(III) complexes of the type Cr(A)(A′)2, Cr(A)2(A′) and Cr(A)3 have been prepared (whereA is either piperidyldithiocarbamate or morpholyldithiocarbamate andA′ is glycine or oxine or acetylacetone moiety). The mixed ligand complexes have been charac terized by elemental analyses, magnetic susceptibility measurements and thermal studies. The complexes show magnetic moment in the range of 3.5–4.3 B.M. which corresponds to three unpaired electrons. TG studies have also been carried out, in order to study the mode of decomposition of the complexes and to evaluate various kinetic parameters.

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Summary

Linear gradient HPLC on a C8 column has been used for separation of individual related substances of amoxicillin listed in the European Pharmacopoeia and a newly identified degradation impurity. The USP plate count for the amoxicillin peak was more than 3000 and USP tailing for the same peak was less than 2.0. Forced degradation studies were conducted on amoxicillin drug substance using ICH stress study guidelines to demonstrate the specificity and stability-indicating nature of the method. A new impurity observed after thermal and alkaline degradation was identified as N-pivaloylamoxicillin. The LOD and LOQ for individual related substances were below 0.045 and 0.086% (w/w), respectively. The method was fully validated in accordance with ICH analytical method validation guidelines. The results of the study prove the method is specific, precise, linear, robust, and can be used for evaluation of the stability of amoxicillin drug substance.

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Abstract  

Simultaneous measurement of gross alpha and gross beta activities by liquid scintillation counting technique using LKB Wallac Quantulus 1220 liquid scintillation counter (LSC) equipped with Pulse Shape Analyzer (PSA) is described. Three sets of pure alpha and pure beta standards simulating the activity concentration values of real samples in terms of α/β activity ratios were used to calibrate the LSC. Calibration methodology for the Quantulus 1220 with respect to the above measurements using 241Am and 90Sr/90Y standards of respective activity concentrations of ~25 dpm and ~104 dpm is described in detail. Also highlighted the need to calibrate the LSC using another set of 241Am and 90Sr/90Y standards of low and high activity concentrations respectively. The practicability and working performance of these calibration plots was checked by the validation trials with test samples spiked with 241Am and 90Sr/90Y covering range of α/β activity ratios from 1:1 to 1:50.

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Abstract  

The identification of isotopic composition of depleted uranium obtained after the reprocessing of spent fuel is very much important as far as their further applications are concerned. The concentration of 235U in the reprocessed uranium will be lower and their depletion depends mainly on the type of the reactor and burn up. The depleted uranium has a variety of applications in nuclear fuel cycle operations and industries warranting quick assessment of its isotopic composition. This paper describes the methodology developed and used for the estimation of 235U concentration in reprocessed uranium in the form of uranyl nitrate solution. A non destructive technique by high resolution gamma-ray spectrometry with HPGe detector has been used for the analysis. The activity ratio of 238U/235U, obtained from the absolute activity measurement on the 185 keV gamma-line of 235U and 1001 keV gamma-line of 234mPa, has been used for the estimation of 235U isotopic content in the sample using a mathematical formula. This method offers rapid and reliable estimate of the 235U concentration in samples comparable with that of mass spectrometry measurements. The results show that 235U concentration in the sample can be determined within 5% error for 10000 seconds counting.

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Cereal Research Communications
Authors: S. L. Krishnamurthy, S. K. Sharma, D. K. Sharma, P. C. Sharma, Y. P. Singh, V. K. Mishra, D. Burman, B. Maji, B. K. Bandyopadhyay, S. Mandal, S. K. Sarangi, R. K. Gautam, P. K. Singh, K. K. Manohara, B. C. Marandi, D. P. Singh, G. Padmavathi, P. B. Vanve, K. D. Patil, S. Thirumeni, O. P. Verma, A. H. Khan, S. Tiwari, M. Shakila, A. M. Ismail, G. B. Gregorio, and R. K. Singh

Genotype × environment (G × E) interaction effects are of special interest for identifying the most suitable genotypes with respect to target environments, representative locations and other specific stresses. Twenty-two advanced breeding lines contributed by the national partners of the Salinity Tolerance Breeding Network (STBN) along with four checks were evaluated across 12 different salt affected sites comprising five coastal saline and seven alkaline environments in India. The study was conducted to assess the G × E interaction and stability of advanced breeding lines for yield and yield components using additive main effects and multiplicative interaction (AMMI) model. In the AMMI1 biplot, there were two mega-environments (ME) includes ME-A as CARI, KARAIKAL, TRICHY and NDUAT with winning genotype CSR 2K 262; and ME-B as KARSO, LUCKN, KARSA, GOA, CRRI, DRR, BIHAR and PANVE with winning genotypes CSR 36. Genotypes CSR 2K 262, CSR 27, NDRK 11-4, NDRK 11-3, NDRK 11-2, CSR 2K 255 and PNL 1-1-1-6-7-1 were identified as specifically adapted to favorable locations. The stability and adaptability of AMMI indicated that the best yielding genotypes were CSR 2K 262 for both coastal saline and alkaline environments and CSR 36 for alkaline environment. CARI and PANVEL were found as the most discernible environments for genotypic performance because of the greatest GE interaction. The genotype CSR 36 is specifically adapted to coastal saline environments GOA, KARSO, DRR, CRRI and BIHAR and while genotype CSR 2K 262 adapted to alkaline environments LUCKN, NDUAT, TRICH and KARAI. Use of most adapted lines could be used directly as varieties. Using them as donors for wide or specific adaptability with selection in the target environment offers the best opportunity for widening the genetic base of coastal salinity and alkalinity stress tolerance and development of adapted genotypes. Highly stable genotypes can improve the rice productivity in salt-affected areas and ensure livelihood of the resource poor farming communities.

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The introduction of new crop varieties is important to improve farm productivity and increase food security in developing countries. This study was conducted to determine the performance of improved varieties of wheat (Triticum aestivum L.), rice (Oryza sativa L.), mungbean [(Vigna radiata (L.) Wilczek] and potato (Solanum tuberosum L.) in comparison to local varieties through farmers’ participatory evaluation. The study was conducted during three years (2006 to 2008) with 948 farmers’ participatory field trials across 18 districts in three Eastern provinces (Nangarhar, Laghman and Kunar) of Afghanistan. One or more improved varieties of wheat, rice, mungbean and potato were compared to the most popular local variety. Data were recorded on the grain yield of wheat, rice and mungbean, and the tuber yield of potato. On average, the improved varieties outyielded local varieties by 69, 57, 70 and 65% for wheat, rice, mungbean, and potato, respectively. Economic analysis in terms of net benefit demonstrated that the adoption of improved varieties resulted in additional incomes of US$ 1840, 1299, 574 and 790 ha-1 for wheat, rice, mungbean and potato, respectively. These findings underline the importance of on-farm farmers’ participatory technology evaluation in developing countries to disseminate new crop varieties to improve farm productivity.

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The present paper reports that significant genetic variability was evident in Fe, Zn, β-carotene, and phytic acid (phytate, PA) contents in a set of 39 diverse maize genotypes collected from maize breeding programme of hill agriculture, India. The Fe, Zn, β-carotene, and PA concentrations were found to be in the range 19.31–50.64 mg kg−1, 12.60–37.18 mg kg−1, 0.17–8.27 µg g−1, and 6.59–7.13 g kg−1, respectively. The genotypes V335, V420, V393, V416, V414, V372, and V351 were identified to have higher concentration of β-carotene, Fe, and Zn but lower amount of PA. Possible availability of the minerals Fe and Zn was determined using molar ratio between PA as inhibitor and β-carotene as promoter for their absorption. The micronutrient molar ratio showed that Fe and Zn traits could be dependent of each other. Low R2 value revealed relation between β-carotene and kernel colour. The selected genotypes could be considered as potential sources of favourable genes for further breeding programs to develop micronutrient enriched maize cultivars.

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