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Abstract  

In the recent paper of this journal [7], a common fixed point theorem in G-complete fuzzy metric spaces under the t-norm Min was proved. We show that this theorem actually holds in more general situations.

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Abstract  

57Fe Mössbauer spectroscopy has been employed to characterize the chemical composition of iron aerosols collected from three distinct groups of sites representing remote, urban and industrially active areas. The Mössbauer spectra clearly show this environmental difference. The fact that the spectra of the samples collected from the remote areas are quite similar to those of clay minerals corroborates the view that iron aerosols are soil derived. Similarly the predominant presence of -Fe2O3 and Fe3O4 in the close vicinity of industrial activities suggests that the Mössbauer spectroscopy can help identify the anthropogenic processes against the natural ones.

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Abstract  

Cobalt(II) complexes of tetradentate Schiff bases of the type CoL [H2L=C20H16N2O2 (H2dsp), C21H18N2O2 (H2dst), C20H15N3O4 (H2ndsp) and C16H16N2O2 (H2salen)] have been synthesized and characterized by UV-visible, IR, and magnetic studies. Various thermodynamic parameters have been calculated for the decomposition step using TG/DTA. C20H14N2O2Co complex has the minimum and C16H14N2O2Co complex has the maximum activation energy.

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Wheat is one of the staple food crops in major areas of the world providing the required carbohydrate and proteins in our diet. A decrease in the total yield of wheat has been observed worldwide due to elevation in environmental temperature. Heat stress causes pollen sterility, drying of stigmatic fluid, pseudo-seed setting, empty pockets in endosperm and shrivelled seeds in wheat. Every plant system has defence mechanisms to cope up with the different environmental challenges. The defence mechanisms of wheat consist of heat responsive miRNAs, signalling molecules, transcription factors and stress associated proteins like heat shock proteins (HSPs), antioxidant enzymes etc. Wheat is sensitive to heat stress especially in stages like pollination to milky dough kernel stages is critical for growth and development. Heat stress causes an oxidative burst inside cell system followed by increase in the expression of various proteins like protein kinases, HSPs and antioxidant enzymes. These stress proteins modulate the defence mechanisms of wheat by protecting the denaturation and aggregation of nascent proteins involved in various metabolic reactions. Genetic variation has been observed with respect to expression and accumulation of these stress proteins. Exogenous treatment of various hormones, signalling molecules and chemicals has been reported to enhance the thermotolerance level of wheat under heat stress. Tools of genetic engineering have been also used to develop wheat transgenic lines with over-expression of stress proteins under heat stress condition. There is an arduous task in front of breeders and molecular biologists to develop a climate smart wheat crop with sustainable yield under the threat of global climate change.

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Abstract  

Bioassay technique is used for the estimation of actinides present in the body based on their excretion rate through body fluids. For occupational radiation workers urine assay is the preferred method for monitoring of chronic internal exposure. Determination of low concentrations of actinides such as plutonium, americium and uranium at low level of mBq in urine by alpha spectrometry requires pre-concentration of large volumes of urine. This article deals with standardization of analytical method for the determination of 241Am isotope in urine samples using Extraction Chromatography (EC) and 243Am tracer for radiochemical recovery. The method involves oxidation of urine followed by co-precipitation of americium along with calcium phosphate. This precipitate after treatment is further subjected to calcium oxalate co-precipitation. Separation of Am was carried out by EC column prepared by PC88-A (2-ethyl hexyl phosphonic acid 2-ethyl hexyl monoester) adsorbed on microporous resin XAD-7 (PC88A-XAD7). Am-fraction was electro-deposited and activity estimated using tracer recovery by alpha spectrometer. Ten routine urine samples of radiation workers were analyzed and consistent radiochemical recovery was obtained in the range 44–60% with a mean and standard deviation of 51 and 4.7% respectively.

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Abstract  

Desorption studies of137Cs from marine sediments by artificial sea water and artificial sea water devoid of individual major cations such as Na, K, Ca, Mg and Sr indicated that only Na and K were effective in the desorption of137Cs. Studies with various ionic strengths ranginf from 0.01 to 1.6M KCl and NaCl solutions showed that KCl desorbs constantly about 45%137Cs at and above an ionic strength of 0.1. In case of NaCl, the percent desorption increases linearly with ionic strength. The difference in desorption by K and Na is attributed to the contraction of the clay mineral layers by K ion and expansion of the layers by Na ion.

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A field study conducted for two years (2002–04) at New Delhi showed that the seed yield (1.80 t ha −1 ) of rocket salad ( Eruca sativa Mill.) obtained by applying 5 t ha −1 pressmud compost based on distillery effluent + half the recommended dose of NPKS (recommended dose: 60 kg N, 13 kg P, 25 kg K and 20 kg S ha −1 ) was on par with the seed yield (1.69 t ha −1 ) recorded with the recommended dose of NPKS. However, the seed yield recorded with the former treatment significantly exceeded that obtained with 5 t ha −1 of a 1:1 mixture of fly ash and distillery effluent + half the recommended dose of NPKS (by 30.4%) or 5 t ha −1 of dry Jatropha curcas leaves + ½ NPKS (by 24.1%). On average, distillery effluent-based pressmud compost + ½ NPKS induced a perceptible increase in the soil-available NPK, recorded after the harvest of rocket salad, compared to the initial fertility status. The uptake of NPKS in the seed and stover of rocket salad was the highest after the application of pressmud compost, closely followed by the recommended dose of NPKS, and the lowest in the control. The residual effect of treatments given to rocket salad was significant on the fodder yield of succeeding sorghum [ Sorghum bicolor (L.) Moench]. The fodder yield recorded with pressmud compost + ½ NPKS was significantly higher than the other treatments. The application of pressmud compost alone was also significantly superior to the same rate of fly ash + effluent mixture or dry Jatropha leaves with respect to the seed yield of rocket salad, residual fertility after the harvest of rocket salad and the fodder yield of succeeding sorghum.

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Journal of Thermal Analysis and Calorimetry
Authors: K. Sreekanth, M. Kondaiah, D. Sravana Kumar, and D. Krishna Rao

Abstract

Ultrasonic velocity, u density, ρ and viscosity, η of mixtures of N,N-dimethyl acetamide with equimolar mixture of ethanol + isopropyl alcohol/isobutyl alcohol/isoamyl alcohol, including those of pure liquids over the entire composition have been measured at T = 308.15, 313.15, and 318.15 K. Using this data, various thermo-acoustic parameters such as deviations in ultrasonic velocity, Δu, isentropic compressibility, Δk s, viscosity, Δη, excess molar volume, and excess Gibb's free energy of activation for viscous flow, ΔG ∗E have been calculated at different temperatures. The calculated deviation and excess functions have been fitted to the Redlich–Kister type polynomial equation. The influence of temperature on the observed negative and positive values of deviation and excess thermodynamic properties has been explained in terms of molecular interactions present in the investigated acid–base liquid mixtures. The experimental data of ultrasonic velocity have been used to check the applicability of velocity models of Nomoto, Van Dael and Vangeel and Junjie and viscosity data have also been availed to test the applicability of standard viscosity models of Grunberg-Nissan, Hind-Mc Laughlin, and Katti-Chaudhary for all the systems investigated at various temperatures.

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Global warming is rising as a serious concern affecting agricultural production worldwide. Rice is a staple food crop and the threshold temperature for its pollination is 35 °C. A rise in temperature above this value can cause pollen sterility and may severely affect fertilization. Therefore, a study emphasizing the rise in temperature with respect to pollen viability was conducted with eleven rice genotypes during kharif seasons of 2010 and 2011 in indigenous field conditions. Increasing mean temperature by 12 °C at full flowering was found to severely affect the spikelet attributes of the crop. All genotypes showed spikelet sterility above 90% during both seasons. The study indicated that increased temperature may limit rice yield by affecting spikelet fertility and grain filling. The net reduction in grain yield was 30.4% and 27.6% in 2010 and 2011, respectively. A clear reduction in pollen size under high temperature was shown by scanning electron microscopy.

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Abstract  

Miniature annular centrifugal contactors are nearly perfect for shielded hot-cell applications during flowsheet evaluation but these contactors require complex maintenance of electrical drive-motors during radioactive experiments. To reduce the number of electrical drives in the shielded cell, an indigenous design of miniature Taylor Couette (TC) mixing based countercurrent differential extraction column has been developed. In this paper, results of mass transfer experiments for an indigenously developed TC column with 30% TBP/aqueous nitric acid solutions are reported. The developed device worked perfectly in counter–current differential mode and demonstrated equivalence to multiple-extraction stages while working with a single electrical drive. The developed TC unit demonstrated operation with a reduced efficiency without flooding even in absence of rotor rotation. This observation is a vital step towards designing of robust contactors, which do not flood during temporary power failure or failure of drive mechanism.

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