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Reaction Kinetics, Mechanisms and Catalysis
Authors: R. Thinesh Kumar, N. Clament Sagaya Selvam, T. Adinaveen, L. John Kennedy, and J. Judith Vijaya

Abstract

Strontium added CoAl2O4 nanocatalysts with spinel structure were prepared by a modified sol–gel method using ethylene diamine followed by sintering at 900 °C. The samples were labeled as CoSA1-900, CoSA2-900, CoSA3-900, CoSA4-900, CoSA5-900, CoSA6-900, where the molar ratios of Co:Sr were 1.0:0.0, 0.9:0.1, 0.8:0.2, 0.7:0.3, 0.6:0.4 and 0.5:0.5 and the aluminum molar ratio was kept constant, 900 referring to the sintering temperature. The effect of Sr addition on the structural and morphological properties of cobalt aluminate nanocatalysts was investigated by X-ray diffraction, Fourier transform infrared spectra, high resolution scanning electron microscopy, energy dispersive X-ray analysis, nitrogen adsorption/desorption isotherms, temperature dependent conductance measurements and thermoelectric power measurements. The addition of Sr improves the performance of the nano cobalt aluminate catalyst towards the selective oxidation of alcohols and decreases the grain size. The effect of solvent, oxidant and reaction time on the Sr(II)-added cobalt aluminate nanocatalysts for the oxidation of benzyl alcohol was studied. Higher activity was obtained for the conversion of benzyl alcohol to benzaldehyde for 0.3 molar percentage Sr(II) added cobalt aluminate catalyst (CoSA4-900) which was used for the selective oxidation of other alcohols. The stability and reusability of the catalyst were also investigated.

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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 gα[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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Journal of Radioanalytical and Nuclear Chemistry
Authors: N. Khare, P. Govil, Pankaj Kumar, A. Mazumder, S. Chopra, J. Pattanaik, S. Balakrishnan, and G. Roonwal

Abstract  

The variations in the concentration of 10Be in the core (SK 200/23) from south western Indian Ocean apparently illuminate past levels of 10Be. The level in the core where lower concentration of 10Be (1.01 × 109 atoms/g) is encountered during the Late Holocene is not at tandem with the Late Holocene southern hemisphere temperature variation. The results further suggest that during last glacial maxima (LGM) the 10Be concentration is higher (2.67 × 109 atoms/g) than the Late Holocene values. The present results, though preliminary, show that local bottom topography seems to have influenced the 10Be concentration at core site. Many studies from different geographic regions need to be undertaken before we finally consider 10Be as yet another strong proxy for palaeoclimatic reconstructions.

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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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Nitrogen use efficiency, more specifically physiological nitrogen use efficiency depends primarily on management of N, one of the major essential nutrients. It is required in increased agricultural production and may possibly cause soil toxicity if fed in excess. Rate of N fertilizer application in fertile agricultural field and improved productivity in sterile soils require the improvement of NUE. A field experiment was therefore conducted to evaluate the effect of different N levels (N0, N50, N100 and N200) on rice genotypes. Vegetative plant growth was found to be reduced under N0 while improved at N200 level. Among the genotypes, highest PNUE (34.94) and correspondingly higher yield (7.15 ton ha−1) was observed for Krishna Hamsa. The other traits viz. plant height, no. of productive tillers and LAI exhibited higher values for Krishna Hamsa as well. Hence these can be utilized as physiological markers for the selection of rice genotypes efficient in N use.

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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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Journal of Radioanalytical and Nuclear Chemistry
Authors: Sharayu Kasar, Sumit Kumar, Aishwarya Kar, K. Krishnan, N. Kulkarni, and B. Tomar

Abstract  

Sorption of Eu(III), an analogue of trivalent actinides (Am, Cm), by amorphous titania as well as different crystalline phases of titania, namely anatase and rutile, have been studied as a function of pH, using 154Eu (half life = 8.8 yrs, Eγ = 123,247 keV) as a radiotracer. The objective of this study was to investigate the effect of the crystalline phase of the titania on their sorption behaviour towards the metal ion. Amorphous titania was prepared by organic route and was converted into anatase and rutile by heating at elevated temperatures based on the differential thermal analysis studies. Eu(III) sorption by all forms of titania rises sharply with the pH of the suspension, with the sorption edge shifting to higher value in the order; amorphous < anatase < rutile. However, the normalization of the sorption data to the surface area of the sorbents resulted in the overlapping of the sorption curves for amorphous and anatase phases, with the data being higher for rutle in the lower pH region, indicating the effect of the crystal phase on sorption behaviour of Eu(III).

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Adenosine diphosphate glucose pyrophosphorylase (AGPase) is the rate limiting enzyme of starch biosynthesis that directly affects the wheat productivity. AGPase and grain growth rate (GGR) discerned to be following strict temperature regimen in wheat disomic chromosome substitution (DCS) lines. The first half of grain filling period had chromosome 1B and 2D as prominent players, whereas second half was mainly controlled by chromosomes 6A and 5B. Chromosome 2D had major contribution towards yield in a specific temperature range of 23 ± 1.5 °C during initial stages of grain filling which can serve as an effective early screening tool for terminal heat tolerance in wheat. Chromosome 2D with highest amylose content can also be utilized to produce low digestibility flour. Grain yield was found to be significantly associated with spikes/plant, grains/spike, grain weight/spike and plant biomass. Further, path analysis indicated that though grains/spike had less direct effect on grain yield but its indirect impact on grain yield via AGPase-21 activity was high.

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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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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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