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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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Journal of Radioanalytical and Nuclear Chemistry
Authors:
Pankaj Kumar
,
J. Pattanaik
,
S. Ojha
,
S. Gargari
,
R. Joshi
,
G. Roonwal
,
S. Balakrishnan
,
S. Chopra
, and
D. Kanjilal

Abstract  

An accelerator mass spectrometry (AMS) facility for measurements of 10Be has been developed by upgrading the 15UD Pelletron accelerator at Inter-University Accelerator Centre (IUAC), New Delhi. Details of the up gradation of the facilities and the measurement procedure are described briefly. Chemical processing for the separation of 10Be from manganese nodules and results of recent experiments on 10Be are presented.

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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  

The paper describes the determination and depth profiling of oxygen in thin oxide films using 18O(p,α)15N nuclear reaction. The excitation function of 18O(p,α)15N nuclear reaction exhibits a resonance at 629 keV and a plateau at 730 keV with uniform cross-section. The resonance is used to determine the depth profile of oxygen in films while the plateau, to estimate its overall concentration. The resonance, characterized by a width of 2.1 keV enables high-depth resolution (~20 nm) measurements and has a probing depth of more than a micron. The paper presents depth profile measurements of oxygen in several metal oxide films (SiO2, TiO2 and HfO2) using this resonance. Possible interferences arising from 15N(p,α)12C, 19F(p,α)16O and 11B(p,α)2α nuclear reactions are also discussed. It has been shown that it can serve as a suitable alternative to 3.05 MeV 16O(α,α)16O resonant scattering which is generally used for depth profiling oxygen. It is, in fact, more reliable and precise in materials that witness significant large angle multiple scattering. It can also be advantageously used to monitor 18O, when used as a tracer.

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A new molybdenum(VI) complex Cs2(NH4)2[Mo3O8(C2O4)3] (CAMO) has been prepared and characterized by chemical analysis and IR spectral studies. Thermal decomposition studies have been made using TG, DTA and DTG techniques. The compound is anhydrous and stable up to 160°C. Thereafter it decomposes in three stages. The first and the second stages occur in the temperature ranges 160–220°C and 220–280°C to give the intermediate compounds having the tentative compositions Cs4(NH4)2[Mo6O16(C2O4)3(CO3)2] and Cs4[Mo6O16(C2O4)2(CO3)2] respectively, the later then decomposing to give the end product Cs2Mo3O10 at 370°C. The end product was characterized by chemical analysis, IR spectral and X-ray studies.

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Abstract  

Diffusion of sodium in Mn and Ti bearing sodium borosilicate glass used for the immobilization of the high level waste at the Waste Immobilization Plant, Tarapur has been studied by heterogeneous isotopic exchange using 24Na as the radiotracer for sodium. The temperature dependence of the self-diffusion coefficient of sodium in the glass was found to follow Arrhenius equation below the glass transition temperature.

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Abstract  

Radiation induced grafting of acrylonitrile (ACN) on ethylene-propene diene terpolymer (EPDM) rubber film was investigated by mutual radiation grafting technique. Effect of experimental variables viz. radiation dose, dose rate, type of solvent and monomer content on extent of grafting was studied. From the kinetic studies a mathematical relation R g α[M]0.7 D 0.68 showing non-linear relationship for rate of grafting with monomer concentration and dose was deduced. The grafted samples showed increased hardness and oil resistance.

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Summary  

A recent study has indicated the feasibility of recycling of chemicals from alkaline waste generated in the preparation of UO3 microspheres by the internal gelation process. Present paper investigates the recycle process, the volume of the secondary uranium waste. Result shows that prior to start the recycle process, the waste solution should be freed from uranium by ion-exchange. Optimized experimental condition to achieve maximum reduction in the volume of uranium based waste is discussed.

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Abstract  

A composite mixture of zirconium molybdate and zirconium tungstate was prepared and studied for the sorption of cesium and strontium as a function of nitric acid, metal ion concentration, time and temperature. The distribution coefficient (Kd) of 7000 ml/g (~90% sorption) and 70 ml/g (~20% sorption) was obtained for the sorption of cesium and strontium in 0.1M nitric acid, respectively. Experimental sorption capacity, b for cesium was found to be 50 mg/g from 0.1M HNO3 and 30 mg/g for strontium from 0.001M nitric acid. The sorption of strontium on the sorbent was accompanied by the absorption of heat but the sorption of Cs+ results in the liberation of heat. Column studies were conducted by following a breakthrough (BT) curve of cesium and strontium up to C/C0=1 and the results are reported.

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Abstract  

An extraction chromatographic procedure for the recovery of fission product palladium has been developed. The method utilizes Cyanex 471X (tri isobutyl phosphine sulfide, TIPS) impregnated on an inert support, Chromosorb-102. Using this method, quantitative uptake of the metal ion is achieved from nitric acid medium. Thiourea as a suitable stripping agent is suggested. Palladium was estimated spectrophotometrically using Arsenazo III as the chromogenic agent and incorporating a modification in the procedure when the aqueous medium contained thiourea.

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