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  • Author or Editor: S. K. Sharma x
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A field study conducted for two years (1995-96 and 1996-97) at the Indian Agricultural Research Institute, New Delhi on a sandy clay loam soil showed that the application of NP increased the total grain production of a rice-wheat-mungbean cropping system by 0.5-0.6 t ha -1 , NK by 0.3-0.5 t ha -1 and NPK by 0.8-0.9 t ha -1 compared to N alone, indicating that the balanced use of primary nutrients was more advantageous than their imbalanced application. The application of farmyard manure (FYM) along with NPK further increased the total productivity of the rice-wheat-mungbean cropping system by 0.3-0.6 t ha -1 , the organic C by 0.13%, the available N by 10.7 kg ha -1 , the available P by 4.7 kg ha -1 and the available K by 15 kg ha -1 compared to NPK after two crop cycles of the system. The results of the present study thus indicate that integrated nutrient management involving FYM and NPK fertilizers is a must for the sustainability of a cropping system.

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Strawberry fruits of three cultivars viz. Camarosa, Chandler and Doughlas were used to prepare wine by four different methods (control, thermovinification, fermented on the skin and carbonic maceration). Physico-chemical characteristics of the cultivar Camarosa were rated superior to Chandler and Doughlas. The must from the fruits fermented on the skin gave the highest rate of fermentation and ethanol content. The application of various treatments improved the fermentation behaviour of treated strawberry musts compared to the control as revealed by their physico-chemical characteristics. Thermovinified wines had many desirable characteristics such as more total phenols, esters and colour with comparable amount of higher alcohols, volatile acids, ethyl alcohol, sugars and anthocyanin. The carbonic maceration resulted in wines with more alcohol, higher pH, lower acidity, lesser higher alcohol and volatile acids than other wines. Fermented on the skin treated wines were typical for higher amount of anthocyanin, lower reducing sugar and total sugar than the control wines. Thermovinified wines, irrespective of cultivars, scored the highest with respect to most of the sensory quality characteristics. Wines from Camarosa cultivar registered many desirable characteristics such as esters, optimum acidity, more red colour units with comparable contents of alcohol and total phenols, while Chandler cultivar had higher amount of ethyl alcohol, more phenols, anthocyanin than other cultivars. Some of these differences are correlated with their initial characteristics, while others have been influenced by method of vinification. Based on the physico-chemical and sensory qualities, the wines from cv. Camarosa was rated the best, though the wines of all the cultivars were acceptable.

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A greenhouse experiment was conducted to study the impact of premethanation (PREME) and postmethanation (POME) distillery effluent applied as pre-sowing irrigation (PSI) along with graded levels of inorganic fertilizers on the grain and straw yield and nutrient content of a rice crop (var. PR 116). Maximum grain yield (29.4 g pot −1 ) was recorded with the application of 100% recommended NPK along with one pre-sowing irrigation (PSI) through POME and the lowest yield (7.4 g pot −1 ) was obtained with 2 PSI applied through PREME without any inorganic fertilizers. The application of POME equivalent to 1 PSI was more effective in increasing the grain and straw yield of rice than no POME application or POME application equivalent to 2 PSI. A significant decrease in yield occurred with the application of 2 PSI of either effluent, and beyond 2 PSI the rice seedlings did not grow.In comparison to POME, the application of PREME increased the content of K (5%), Cu (10%), Fe (17%) and Mo (21%), but decreased that of P (12%), S (5%) and Mg (11%) in rice grain. In rice straw an increase was only observed in K (9%) and Mo (14%), while the contents of other nutrients (P, S, Zn, Cu, Mn) decreased by 8 to 21%. An increase in the level of effluent from 0 to 2 PSI significantly increased the content of N (by 21%), K (11%), S (10%), Zn (9%), Cu (21%) and Mo (8%), but decreased that of P (16%) and Mg (19%) in rice grain. In the case of rice straw, an increase in K (28%), S (32%), Cu (65%) and Mo (45%) content was recorded. Effluent application, inorganic fertilizers and their interactions had a significant effect on both the grain and straw yields and on the nutrient concentration in the plants.

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Abstract  

Effect of various doses of gamma radiation on the ion-exchange capacity, distribution coefficient values, elution behaviour, pH titration and infrared spectra of some thermally stable inorganic ion exchangers has been studied systematically. No change has been observed in the ion-exchange capacity, elution behaviour and the infrared spectra of the materials irradiated up to a total dose of 3·108 rad, while, a change has been observed in their pH-titration and distribution behaviour.

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Every geophysical exploration method has non-uniqueness/ambiguity due to which interpretation is often misleading. If two or more data sets that deal with different physical properties are interpreted jointly then the combined study reduces the ambiguities in either method significantly. For layered structures magnetotelluric and seismic method provide information about the conductivities, velocities and thicknesses of the layers, where the thicknesses are the common parameters of seismic and magnetotelluric models. Assuming that the conductivity and velocity discontinuities are identical, the joint inversion of the two methods can improve the reliability of the estimation of thicknesses. In this paper on synthetic data will be shown, that the joint inversion yields better layer parameters, than the individual magnetotelluric or seismic inversions. The joint inversion decrease the effect of the equivalence, which at the magnetotelluric inversion often leads to misconclusion.  As inversion technique the simulated annealing and the linearized inversion will be used. In the present work, attempt is made to study the seismic refraction and magnetotelluric data to delineate reliable subsurface information.

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Abstract

A number of silicon-based inorganic ion exchangers were synthesized under different conditions of preparation. The original and regenerated ion exchange capacities (IECs) were determined. Thermal stability of these materials was investigated in the temperature range of 40–800 °C. The gain/loss of IEC was studied as a function of temperature. These exchangers show a higher IEC and its retention to a considerable extent at elevated temperatures when compared to that of corresponding ion exchangers which do not contain silica. The thermogravimetric curve shows greater percent mass loss in H+ form of the exchanger than in K+ form. Dehydration studies seem to throw some light on the state of water molecules present in various samples. The empirical formula and the tentative structure for stannic arseno silicate have also been proposed.

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Abstract  

Solvent extraction of U(VI) with di-isodecyl phosphoric acid (DIDPA)/dodecane from nitric acid medium has been investigated for a wide range of experimental conditions. Effect of various parameters including nitric acid concentration, DIDPA concentration, temperature, stripping agents, and other impurities like rear earths, transition metal ion, boron, aluminum ion on U(VI) extraction has been studied. The species extracted in the organic phase is found to be UO2(NO3)(HA2)·H2A2 at lower acidity (<3.0 M HNO3). Increase in temperature lead to the decrease in extraction with the enthalpy change by ∆H = −16.27 kJ/mol. Enhancement in extraction of U(VI) from nitric acid medium was observed with the mixture of DIDPA and tri butyl phosphate (TBP). The stripping of U(VI) from organic phase (DIDPA–U(VI)/dodecane) with various reagents followed the order: 4 M H2SO4 > 5% (NH4)2CO3 > 8 M HCl > 8 M HNO3 > Water. High separation factors between U(VI) and impurities suggested that the use of DIDPA for purification of uranium from multi elements bearing solution.

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Abstract

The phase diagram of 1,4-dibromobenzene (DBB) with pyrogallol (PG) shows the formation of a monotectic and a eutectic alloys at 0.12 and 0.99 mol fractions of DBB, respectively. The phase equilibrium shows the large miscibility gap region with the upper consolute temperature 159.0 °C at 0.55 mol fraction of DBB. Growth kinetics of pure compounds and their monotectic and eutectic at different undercooling (ΔT) obey Hillig–Turnbull's equation: v = uT)n. Thermodynamic parameters such as enthalpy of mixing, entropy of fusion, interfacial energy, roughness parameters and excess thermodynamic functions were computed based on enthalpy of fusion values obtained from DSC studies. The Cahn wetting condition is applicable for monotectic alloy. The optical microphotographs of binary alloys show lamellar and dendritic features.

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Abstract  

Radiotracers are extensively used in many industries for trouble shooting and optimization of process parameters leading to considerable savings in time and huge economic benefits. In chemical and petrochemical industries different gases and vapours flowing in the conversion reactors play a major role in the final production. Gaseous radiotracers are ideal to study hydrodynamics of gas phases in process vessels. 41Ar and 79Kr are the preferred gaseous radiotracers for such studies. Owing to the increase in demand from Indian industries for gas phase radiotracers, efforts have been made to produce 41Ar and 79Kr indigenously by irradiation of 40Ar and enriched 78Kr gaseous targets in research reactors. Prequalification of the containers used, safety aspects concerning accidental rupture and mandatory tests necessary for irradiation of gaseous targets in the reactors have been studied. The paper describes some of the important safety aspects involved and the results of trial irradiations on the production of 41Ar and 79Kr radiotracers. Standardization of suitable assay protocols for their regular production and supply for applications in industries is also described.

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In the present investigation, expression of genes related to Na+ exclusion such as salt overly sensitive (TaSOS1) and Na+/H+ antiporter (TaNHX1) and proline accumulation such as pyrroline-5-carboxylate reductase (P5CR) and glutamate synthase (GOGAT) was studied in seedlings of Kharchia 65 (Kh 65, salt tolerant) and HD 2009 (sensitive) under salt stress (ECe, 12 dSm–1) and controlled conditions. As compared to HD 2009, Kh 65 showed significantly lower accumulation of Na+ (p < 0.01) and higher accumulation of proline (p < 0.05) in leaf blade under salt stress. The relative expression of TaSOS1 increased significantly (p < 0.001) in roots of Kh 65 (4.31-fold) while it decreased in HD 2009. There was significantly higher (p < 0.01) relative expression of TaNHX1 (27.57-fold) in leaf and 3.07-fold in roots of Kh 65 as compared to 3.65- and 0.87-fold increase in leaf and roots of HD 2009, respectively, under salt stress. There was significantly (p < 0.05) higher accumulation of proline as compared to HD 2009 in leaf tissues. There was significantly higher (p < 0.01) expression of P5CR (5.23-fold in leaf and 8.77-fold in the root) and glutamate synthase (6.0- fold in roots) in Kh 65 as compared to HD 2009. The study demonstrated that upregulation of genes for Na+ exclusion in root and compartmentation in leaf and increased proline concentration are associated with tolerance to salinity stress in wheat. The information will be useful for improving wheat genotypes for salt tolerance.

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