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Abstract  

Partitioning of minor alpha-emitting actinides, especially U, Pu and Am from medium active alkaline waste is possible from intermediate level liquid wastes (ILLW) produced during spent fuel reprocessing following Purex process. This paper deals with the efficient removal of alpha-activity from ILLW by solvent extraction process. Counter current batch extraction with O/A ratio 2:1 as well as multistage mixer settler has demonstrated that most of the alpha-activity was removed from the alkaline effluents using 20% Versatic-10 (V-10) in dodecane after giving 3 to 4 contacts, thus converting alkaline waste as non-alpha waste. Under the optimum conditions (pH 9.0-9.5 and VA-10), both Pu(IV) and Am(III) are highly extractable whereas U(VI) is relatively poorly extracted. To assess the applicability of this process for regular treatment of the waste, a feasibility study on pilot plant scale using six stage mixer settler was operated to treat the ILLW. The results indicated that almost >99.90% alpha-emitting actinides are removed. Dilute nitric acid (0.5M HNO3) served as the most efficient strippant for all these actinides. This facilitate an easy regeneration of the extractant which can be recycled. This method is useful in obtaining alpha-free wastes and had positive impact on ease and safety aspects during subsequent waste treatment and long term storage.

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Summary  

Twenty bhasmas based on Ca, Fe, Zn, Hg, Ag, K, As, Cu, Sn and gemstones have been analyzed for main constituent elements along with minor (Na, K, Mg, Ca, P), trace (Cr, Mn, Fe, Co, Cu, Zn, Hg) and toxic elements by instrumental neutron activation analysis (INAA) including their C, H, N and S contents. Siddhamakaradhwaja, an Hg preparation and Swet parpati of K were found to be stoichiometrically HgS and KNO3

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One thousand four hundred and eighty three spring wheat germplasm (Triticum aestivum L.) lines comprising Indian as well as exotic lines were screened for resistance to spot blotch disease during winter 2014-15 at hot spot locations i.e., Banaras Hindu University, Varanasi and Uttar Banga Krishi Vishwavidyalaya, Cooch Behar. Severity of the disease at different stages beginning from tillering to dough stage was recorded. Location Severity Index (LSI) of Varanasi was higher than Cooch Behar. Twenty eight accessions were resistant or highly resistant at both locations. These 28 accessions were validated during the winter season (2015–2016). These germplasm were also evaluated at four environments for agronomic traits. Out of 28 accessions, seven (IC564121, IC529684, IC443669, IC443652, IC529962, IC548325 and EC178071-331) were highly resistant across the locations and over the years of study. These accessions comprised one exotic and six indigenous accessions belonging to Uttarakhand and Haryana. Two lines (IC529962 and IC443652) had higher yield than the best check at all the locations. These lines showing highly resistant reaction alongwith wider adaptability can be expedited for direct cultivation or for the development of high yielding and disease resistant cultivars. These lines can also be used for identification of novel resistance gene using allele mining tools and their deployment for the development of spot blotch resistant cultivars.

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Abstract

The solid–liquid phase equilibrium data of two binary organic systems, namely, urea (U)–3-aminophenol (AP) and 3-hydroxybenzaldehyde (HB)–β-napthaol (BN) show formation of a eutectic in each case. The enthalpies of fusion of the pure components and binary eutectics have been determined using differential scanning calorimeter (Mettler DSC-4000) system. The thermal properties of the materials such as heat of mixing, entropy of fusion, roughness parameter, interfacial energy and excess thermodynamic functions were computed using the enthalpy of fusion values. The microstructures of eutectics were developed using unidirectional thermal gradient and interested region were photographed.

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Journal of Radioanalytical and Nuclear Chemistry
Authors: Pritty Rao, G. Reddy, S. Vikram Kumar, J. Ramana, N. Chattopadhyay, A. Basu, Seema Srivastava, R. Sarin, V. Raju, and Sanjiv Kumar

Abstract  

The paper describes the simultaneous determination of 14N and 15N isotopes in opium by proton induced γ-ray emission (PIGE) technique. The isotopic ratio of 14N and 15N is a useful parameter for assigning provenance of (seized) illicit drugs. The measurement, non-destructive in nature, is performed on pellets made up of opium powders and is based on the prompt detection of 2.313 and 4.4 MeV γ-rays emanating from 14N(p,p′γ)14N and 15N(p,αγ)12C nuclear reactions respectively, induced simultaneously by 3.6–3.8 MeV proton beam. Positive as well as negative deviations from the natural isotopic abundance (99.63:0.37) were observed in the samples. The precision of the measurements is about 4%. The methodology provides an easy and rapid approach to determine the isotopic ratio of 14N and 15N and has been used for the first time in the analysis of opium.

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Abstract

Background

Pulmonary Arterial Hypertension (PAH) carries a poor prognosis in both adult and pediatric patients. It is a life-threatening condition in newborns. Current recommendations advocate the use of targeted monotherapy as a first-line approach for the treatment of Persistent Pulmonary Hypertension of the Newborn (PPHN). In case of an inadequate clinical response to treatment, an addition of a second or third agent is considered. PAH is usually managed with a phosphodiesterase 5 inhibitor or an endothelin receptor blocker. There are limited pediatric studies that address questions like which class of therapy should be initiated first or if a combination should be initiated together. With this background, the present study was initiated to compare the efficacy, safety, and tolerability of bosentan as an adjuvant to sildenafil and sildenafil alone in PPHN.

Results

A total of 40 patients were enrolled in the study. Out of them, 26 were males (65%) and 14 were females (35%). PPHN was most commonly seen in the 29 (72.5%) of participants with a history of first order birth. Mean duration of symptoms was 14.05 ± 2.06 days. The participants were randomized to two groups. Group A consisted of total 25 participants that received both bosentan and sildenafil and group B had 15 participants that received sildenafil alone. Both groups were comparable in terms of birth weight and present weight, consanguinity, and mode of delivery. Efficacy was determined by the reduction in mean baseline Pulmonary Artery Systolic Pressure (PASP). PASP in group A was 75.56 ± 10.62 mm Hg and in group B was 64.86 ± 12.25 mm Hg which was not statistically significant (P > 0.05). PASP on the third and seventh day in group A were 43.72 ± 8.63 and 24.47 ± 3.52 mm Hg compared to 42.28 ± 9.43 and 27.276 ± 8.38 respectively in group B which was statistically significant (P < 0.05).There were two deaths each in both groups. Two participants in Group A developed liver function abnormalities. None of the participants in Group B had adverse effects.

Conclusion

Most common clinical manifestations were nonspecific. Cardiovocal syndrome was common in PPHN. We conclude that oral sildenafil treatment is a safe, simple and effective treatment for persistent pulmonary hypertension in newborn. Combination of bosentan with sildenafil is more effective and safe in reducing pulmonary artery (PA) pressures in high-risk patients with PPHN.

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