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Ten dicoccum wheats were analyzed for their physico-biochemical and milling properties to evaluate the pasta making potential. Dicoccums showed higher protein content and mixograph midline peak values compared to durum variety MACS2846. Mixographic properties of dicoccums were poor compared to durums, due to lower functional visco elastic gluten content. Dicoccums were poorer in milling properties compared to durums, due to lower test weight and thousand-grain weight. Among dicoccums, DDK 1025 showed high micro SDS sedimentation volume and strong mixographic properties, but values were still lesser compared to durum MACS 2846. HMW glutenin subunits in recently developed/released dicoccums were similar to durum parents and were different from the older dicoccums. LMW glutenin subunits, however, were similar to dicoccum parents, except in DDK 1025 which showed LMW glutenin subunits similar to durum wheat. To breed high quality dicoccum wheat for pasta products, breeders should select superior glutenin subunits composition, along with better mixograph properties, keeping morpho-botanical characteristics of dicoccum wheat.

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Abstract  

A method for the recovery and purification of233U from phosphate containing analytical waste is developed. Extraction studies with DBDECMP (Di-butyl, N, N-diethylcarbamoyl-methyl phosphonate) in xylene were carried out to explore the feasibility of separation and purification of233U from such wastes. Based on the data obtained, optimum conditions for the recovery of233U are suggested.

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Abstract  

A differential spectrophotometric method has been developed for plutonium in hexavalent state using a double beam spectrophotometer. The absorbance measurements were made at 835 nm in 4M sulfuric acid using a 5 cm cell. In the method developed the absorbance of six Pu(VI) standards, taken in the sample cell, were recorded against a molybdenum blue solution of appropriate intensity in the reference cell. A least-squares fit of data on absorbance and concentration of plutonium standards gave slope F and intercept Co which were used to determine the unknown concentrations using the relationship, C=C0+F·Ar where Ar is the absorbance of a plutonium solution of unknown concentration C mg/g. Various parameters like choice of acid and acidity, slit width, oxidant etc. were studied and the conditions optimized. Plutonium in the concentration range of 0.1–0.3 mg/g could be determined with a precision of ±0.5%. Uranium does not interfere. The method is useful for the analysis of a large number of samples on a routine basis.

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Abstract  

Extraction studies have been carried out to explore the feasibility of separation of Pu(IV) from phosphate containing analytical wastes generated in the laboratory. Distribution data on the extraction of Pu(IV) from DBDECMP (di-butyl, N,N-diethylcarbamoyl methyl phosphonate) in xylene from an aqueous nitric acid and its mixture with sulfuric as well as with sulfuric and phosphoric acids were obtained. Based on the data obtained, the conditions for the recovery of plutonium from such waste solutions are suggested.

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Abstract  

A differential spectrophotometric method has been developed for uranium in presence of plutonium by making absorbance measurements at 420 nm in 4M H2SO4 using 5 cm cells. The absorbance measurements are made with two independent sets of standards: (1) having uranium only and (2) having uranium and plutonium in a fixed ratio R, against a uranium solution of high absorbance (1A) in the reference beam. A least-squares fit of data on absorbance and uranium concentration in the two cases gave two slopes m1 and m2, which were used to determine the concentration of uranium using the relationship CU=C0+m1·[AT-(1/m2–1/m1) R·CPu] where AT is the relative absorbance of uranium and plutonium at 420 nm and C0 is the intercept corresponding to slope m1 for pure uranium standards and m2 is the slope for mixed uranium and plutonium standards. A knowledge of CPu, the plutonium concentration, is essential and is obtained by differential spectrophotometric measurements at 835 nm by oxidizing plutonium to its hexavalent state. In the same aliquot, plutonium could be determined with a precision of better than ±0.5% and uranium with a precision of better than ±1.0%.

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Journal of Radioanalytical and Nuclear Chemistry
Authors: O. T. DeJesus, L. G. Flores, A. K. Converse, R. M. Bartlett, D. Murali, R. Jeraj, T. R. Oakes, R. J. Nickles, and C. J. Jaskowiak

Summary  

Exposure to several environmental chemicals in utero is associated with subtle deleterious effects in cognitive, motor and behavioral functions. In order to assess in utero exposure to possible neurotoxins, fetal brain uptake of an exogenous compound given to a pregnant rhesus macaque was investigated using PET/CT imaging. CT clearly delineated the fetus which allowed the time course of the PET tracer in the fetal brain and other organs to be monitored. This study demonstrates the feasibility of quantifying the absolute fetal uptake of chemicals given systemically to the mother.

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