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Abstract  

The sum peak intensity relative to its single peak was determined in various compounds of133Ba by the technique of gamma-ramma-ray sum peaks observed in a single HPGe detector. The change in intensity ratio was used to determine the time integral perturbed angular correlation coefficients for BaCl2, Ba(NO3)2, BaSO4, Ba-EDTA, Ba-MES and Ba-BSA compounds.

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Abstract  

The sum peak method based on the phenomenon of perturbed angular correlation has been applied to study the nuclear quadrupole interaction frequencies at133Cs which is followed by electron-capture decay of133Ba. These values are used to determine the z-component, which is the largest one of the electric field gradient. The electric field gradient /EFG/ is found to vary with different compounds of barium. The method is found to be useful in describing the chemical influences on the attenuation of angular correlations and hence in the study of EFG.

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The CERES-rice model (version 4.0) was calibrated and validated using the data from a field experiment carried out during the rainy season of 2004 and 2005 at Shalimar, Srinagar (35° 5′ N latitude and 74° 89′ E longitude, 1587 m above the mean sea level, India. The experiment included six rice cultivars each transplanted on 25 May, 10 June and 25 June. Data of 25 May transplanting was used for model calibration and development of the genetic coefficients of the rice cultivars. The predicted and observed dates of phenological events were in close agreement with root mean square error (RMSE), mean absolute error (MAE) and D-index of 5.0 days, 4.3 days and 0.91, respectively, for anthesis and 3.7 days, 3.1 days and 0.91, respectively, for physiological maturity of the crop. The predicted and observed grain yields were also very close with a RMSE of 0.63 Mg ha −1 , MAE of 0.58 Mg ha −1 and D-index of 0.89, respectively. Corresponding values for above ground biomass was 1.17 Mg ha −1 , 1.01 Mg ha −1 and 0.82. Sensitivity test showed that simulated yield responded to temperature and atmospheric CO 2 concentration. Nitrogen 240 kg ha −1 at 25 May transplanting, recorded highest simulated grain yield (9.71 Mg ha −1 ). Further, 3 seedlings hill −1 produced highest simulated grain yield. The results suggest that the model can be applied in the temperate Kashmir to estimate crop productivity and optimize the management practices.

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Abstract  

The thermodynamic behaviour of bulk metallic glass (BMG) forming melts have been studied by analyzing the temperature dependence of the Gibbs free energy difference (∆G), entropy difference (∆S) and enthalpy difference (∆H)between the undercooled melt and the corresponding equilibrium solid phases. The study is made by calculating∆G, ∆S and ∆H in the entire temperature range T m (melting temperature) to T g (glass transition temperature) using the expressions obtained on the basis of Taylor’s series expansion. The entire analysis is made for La-based five samples of BMGs; La55Al25Ni20, La55Al25Ni15Cu5, La55Al25Ni10Cu10, La55Al25Ni5Cu15, and La55Al25Ni5Cu10Co5 and a comparative study is also performed between present results and results obtained in the framework of expressions proposed by earlier workers. An attempt has also been made to study the glass forming ability for BMGs.

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Abstract

The glass-forming ability (GFA) of bulk metallic glasses (BMGs) has been analyzed on the basis of the thermodynamic parameters such as the specific heat difference ΔC p m between the undercooled liquid and corresponding equilibrium solid phase at the melting temperature T m, entropy of fusion ΔS m, and the residual entropy ΔS R and characteristic temperatures, such as the Kauzmann temperature T K, glass transition temperature T g, and the melting temperature T m. The entire study is performed by analyzing the variation of critical cooling rate R c with T K/T m, ΔC p mS m, (T gT K)/T m and ΔS RS m for a large number of BMGs. The variation of T K/T m and ΔS RS m with ΔC p mS m has also been studied for BMGs. It has been found that materials having large ΔC p mS m exhibit large T K/T m and such materials require low R c for the glass formation. At the same time, it has also been found that materials having large T K/T m exhibit low ΔS RS m and such materials need a low R c for the glass formation. Attempt has also been made to correlate R c with T K/T m, ΔC p mS m, (T gT K)/T m and ΔS RS m for BMGs.

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Abstract  

The - sum peak method based on the phenomenon of perturbed angular correlation has been applied to see the effect of chemical environment on the directional correlation coefficients of various cascades and to check the suitability of160Tb as a probe. No change in sum peak intensity ratios for different pH and gelatin concentration values have been seen.

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A new lichenicolous fungus Buelliella indica colonising on the thallus of Graphis longiramea is described from the state of Nagaland, a part of the Indo-Burma biodiversity hotspot region in India. It is characterised by its brown epihymenium, much smaller ascospores with dimensions of 11.5–13.8 × 4.8–6 µm and the new host Graphis.

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Maize protein quality is deficit in essential amino acids, lysine and tryptophan. These constraints of o2 (opaque2) are corrected in genetically improved, hard endosperm QPM (Quality Protein Maize). An integrated strategy of phenotypic selection for endosperm modifiers and molecular marker-assisted foreground and background selection has been used in present study. The QPM donors were, CML 161, DMRQPM 58, CML 176 and CML 141 whereas, normal maize inbreds were CM 212, V338, V361, V336, V341, V351, CM 141 and V335. The inbreds were subjected to parental polymorphism survey between non-QPM and QPM using CIMMYT based three SSR markers, viz. phi057, umc1066 and phi112. Two markers, viz. phi057 and umc1066 exhibited co-dominant reactions, while phi112 was dominant in nature. Finally, two combinations V335 × CML 141 and V351 × CML 141 were considered for conversion program. Foreground selection was exercised using o2 specific marker umc1066 in BC1 and BC2 generations, while background as well as foreground selection was exercised in BC2F3 generation to recover the genome of recurrent parent up to extent of 80 to 100% with the help of SSR markers distributed across the whole maize genome. The tryptophan concentration in endosperm protein was significantly enhanced and the converted maize lines had almost twice the amount of lysine and tryptophan than normal maize inbreds.

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A new lichenicolous fungus Melaspilea nitidochapsae colonising on the thallus of Nitidochapsa leprieurii (Mont.) Parnmen, Lücking et Lumbsch is described from India. The new species differs from other known species colonising lichen family Graphidaceae by having completely carbonised exciple, hyaline to pale brown transversely 1-septate ascospores and a different host.

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