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Synthesis and structural studies of some first row transition metal complexes of salicylaldehyde hydrazone
(1979) R.C. Aggarwal; N.K. Singh; R.P. Singh
[No abstract available]
Magnetospheric electron temperatures inferred from whistler observations at low latitudes
(2008) Krishna K. Singh; A.K. Singh; M. Altaf; M.M. Ahmad; B.L. Koul; Lalmani; R.P. Singh; Jaipal Singh; Balraj Kumar
Whistler observations during night times made at low latitude Indian ground stations Jammu (geomag.lat.22° 26'N; L= 1.17), Nainital(geomag.lat., 19° 1' N; L= 1.16) and Varanasi (geomag.lat., 14°55'N; L = 1.11) are used to deduced electron temperatures in the vicinity of the magnetospheric equator. The accurate curve fitting and parameter estimation technique are used to compute nose frequency and equatorial electron densities from the dispersion measurements of short whistlers recorded at Jammu, Nainital and Varanasi. These computed parameters are further used to estimate the magnetospheric electron temperatures from the dispersion analysis of short whistlers observed at low latitudes which are in good agreement with the results reported by other workers. © 2008 IACS.
Grain yield, adaptation and progress in breeding for early-maturing and heat-tolerant wheat lines in South Asia
(Elsevier B.V., 2016) S. Mondal; R.P. Singh; E.R. Mason; J. Huerta-Espino; E. Autrique; A.K. Joshi
Maintaining wheat productivity under the increasing temperatures in South Asia is a challenge. We focused on developing early maturing wheat lines as an adaptive mechanism in regions suffering from terminal heat stress and those areas that require wheat adapted to shorter cycles under continual high temperature stress. We evaluated the grain yield performance of early-maturing heat-tolerant germplasm developed by CIMMYT, Mexico at diverse locations in South Asia from 2009 to 2014 and estimated the breeding progress for high-yielding and early-maturing heat-tolerant germplasm in South Asia. Each year the trial comprised of 28 new entries, one CIMMYT check (Baj) and a local check variety. Locations were classified by mega environment (ME); ME1 being the temperate irrigated locations with terminal high temperature stress, and ME5 as hot, sub-tropical, irrigated locations. Grain yield (GY), days to heading (DTH) and plant height (PH) were recorded at each location. Effect of temperature on GY was observed in both ME1 and ME5. Across years, mean minimum temperatures in ME1 and mean maximum temperatures in ME5 during grain filling had significant negative association with GY. The ME1 locations were cooler that those in ME5 in the 5 years of evaluations and had a 1-2 t/ha higher GY. A mean reduction of 20 days for DTH and 20 cm in PH was observed in ME5. Negative genetic correlations of -0.43 to -0.79 were observed between GY and DTH in South Asia during 2009-2014. Each year, we identified early-maturing germplasm with higher grain yield than the local checks. A positive trend was observed while estimating the breeding progress across five years for high-yielding early-maturing heat tolerant wheat compared to the local checks in South Asia. The results suggests the potential of the high-yielding early-maturing wheat lines developed at CIMMYT in improving wheat production and maintaining genetic gains in South Asia. © 2016 The Authors.
Electrodeposited semiconducting CuInSe2 films. I. Preparation, structural and electrical characterisation
(1986) R.P. Singh; S.L. Singh; S. Chandra
Ternary compound semiconductor CuInSe2 film has been deposited cathodically under galvanostatic conditions from an aqueous solution containing CuCl2, InCl3 and SeO2. The deposition parameters have been optimised for electrodeposition of CuInSe2. Structural characterisation of the deposited film has been carried out using EDAX and EM studies. Optical absorption study shows that the band gap of the deposited material is 1.08 eV. The resistivity and trap density of the electrodeposited film are respectively approximately 103 ohm cm and approximately 1014 cm-3 as determined by I-V characteristics.
Rotational bands in 113Sb
(American Physical Society, 2013) P. Banerjee; S. Ganguly; M.K. Pradhan; H.P. Sharma; S. Muralithar; R.P. Singh; R.K. Bhowmik
Rotational bands in 113Sb, populated in the reaction 100Mo(19F,6n) at a beam energy of 105 MeV, have been studied. Two previously reported strongly coupled high-K bands have been extended and a new sequence of five states, linked to the positive-parity high-K band through interband transitions, is proposed. A comparison of the experimental B(M1)/B(E2) ratios for the latter band with the predictions of the geometrical model of Dönau-Frauendorf suggests that the states are axially symmetric with a moderate quadrupole deformation of β2=0.20. Present directional correlation orientation and γ-ray polarization studies indicate that the negative-parity states built upon the 3045 keV isomeric level involve a high-Ω πh11/2 orbital and have an oblate shape. Mean lifetimes for eight states belonging to the prolate-deformed πh 11/2 band have been measured from Doppler shift attenuation data. The results suggest a large average quadrupole deformation of β2=0. 32±0.03 for states up to 10217 keV. The decrease of the B(E2) rates for the 9063- and 10217 keV states may be interpreted as a signature of band termination at high spin. © 2013 American Physical Society.
Potential benefits and risks of land application of sewage sludge
(2008) R.P. Singh; M. Agrawal
Sewage sludge, also referred as biosolids, is a byproduct of sewage treatment processes. Land application of sewage sludge is one of the important disposal alternatives. Characteristics of sewage sludge depend upon the quality of sewage and type of treatment processes followed. Being rich in organic and inorganic plant nutrients, sewage sludge may substitute for fertilizer, but availability of potential toxic metals often restricts its uses. Sludge amendment to the soil modifies its physico-chemical and biological properties. Crop yield in adequately sludge-amended soil is generally more than that of well-fertilized controls. Bioavailability of metals increases in sludge amended soil at excessive rates of application for many years. Plants differ in their abilities to absorb sludge-derived metals from the soil. The purpose of this paper is to review the available information on various aspects of sewage sludge application on soil fertility and consequent effects on plant production to explore the possibility of exploiting this byproduct for agronomy and horticulture. © 2007 Elsevier Ltd. All rights reserved.
New method for the spectrophotometric determination of phosphate as molybdenum blue using ferrous ammonium sulphate as reducing agent
(Springer-Verlag, 1970) T.S.B. Narasaraju; R.P. Singh; V.L.N. Rao
[No abstract available]
Variation of quantum well infrared photodetectors parameter with an applied electric field
(2011) R.P. Singh; D.P. Singh
A model is presented for the performance of quantum well infrared photodetectors (QWIPs) utilizing intersubband electron transitions and tunneling injection electrons. The dark current and the responsivity are derived as functions of the QWIP parameters, including the number of the QWs and electric field dependent capture probability in an analytical form. © 2011 SumDU.
Lightning produced nitrogen oxides in the lower atmosphere - An overview
(2005) R.P. Singh; R.P. Patel; Rajesh Singh; R.N. Singh
Nitrogen oxides are dominant constituents of the atmospheric lower regions namely, troposphere and stratosphere. Lightning phenomenon plays an important role in governing the odd nitrogen oxides in the lower atmosphere and hence in global change process. In this paper, studies made by different workers on the lightning produced nitrogen oxides and other related phenomena have been reviewed. Studies in this direction are'very sparse in India. Besides the ground based, balloon-borne and satellite-borne measurements, aircraft measurements in India and elsewhere are essential for providing global information. In order to make reliable measurements the experimental site should be in remote areas free from heavy industrial pollution, so that the contaminations due to direct influence of anthropogenic activities are avoided.
Ug99 race of stem rust pathogen: Challenges and current status of research to sustain wheat production in India
(2008) A.K. Joshi; B. Mishra; M. Prashar; S.M.S. Tomar; R.P. Singh
A highly virulent race of stem rust of wheat caused by Puccinia graminis Pers. f.sp. tritici Errikss. & Henn. was detected in 1999 in Uganda and may pose a major threat to wheat crop in many countries including India in coming years. This race is commonly known as Ug99 and designated as TTKSK based on North American system of nomenclature. The race Ug99 carries virulence to several genes commonly present in global wheat germplasm including Sr31, known to be present in several leading spring and winter wheat cultivars and germplasm. Emergence of a new variant TTKST that overcame resistance of Sr24 gene causing severe stem rust epidemic in Kenya has further aggravated the threat. The occurrence of Ug99 is now widespread in wheat growing areas of Kenya and Ethiopia and has rendered many popular cultivars susceptible. It crossed the red sea to Yemen and migrated to Sudan in 2006, and its presence was confirmed in Iran in 2007. Therefore, development and dissemination of suitable resistant cultivars in a relatively short time before rust migrates to South Asia is of utmost importance for food security. Indian wheat programme in collaboration with CIMMYT and Kenya has identified some wheat cultivars and genetic stocks that are resistant to Ug99. However, area coverage to these resistant cultivars must increase to occupy about 3-5% of the total area for enough seed procurement to replace the current popular susceptible cultivars, when Ug99 reaches Indian Subcontinent. Although, several alien genes can provide resistance, the long-term strategy should focus on achieving durable resistance by rebuilding the Sr2 complex.

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