Showing papers by "Banaras Hindu University published in 1985"
TL;DR: In this article, a review of the progress made in the last several years in understanding the properties of disordered electronic systems is presented, focusing on the metal-to-insulator transition and problems associated with the insulator.
Abstract: This paper reviews the progress made in the last several years in understanding the properties of disordered electronic systems. Even in the metallic limit, serious deviations from the Boltzmann transport theory and Fermi-liquid theory have been predicted and observed experimentally. There are two important ingredients in this new understanding: the concept of Anderson localization and the effects of interaction between electrons in a disordered medium. This paper emphasizes the theoretical aspect, even though some of the relevant experiments are also examined. The bulk of the paper focuses on the metallic side, but the authors also discuss the metal-to-insulator transition and comment on problems associated with the insulator.
4,095 citations
TL;DR: In this article, the removal of Cu(II) by adsorption on fly ash has been found to be concentration, pH and temperature dependent, indicating the process to be diffusion controlled.
513 citations
TL;DR: The current staus of research of free and glycosylated alkaloids occuring in members of the genus Crinum is reviewed in this paper, where the distribution, isolation, spectral properties, structural properties, inter conventions and biological acitivities of these alkaloid are presented.
159 citations
TL;DR: In this article, it was shown that quasicrystals with icosahedral point group symmetry occur in a rapidly solidified Mg32 (Al, Zn)49 alloy chosen on the basis of its equilibrium crystal structure.
Abstract: It has been established that quasicrystals with icosahedral point group symmetry occur in a rapidly solidified Mg32 (Al, Zn)49 alloy chosen on the basis of its equilibrium crystal structure. This alloy has a natural tendency to form icosahedral atomic clusters stabilised by size difference amongst constituent atoms. Results highlight the relationship between equilibrium crystal structure and the tendency to form quasicrystals.
112 citations
TL;DR: In this article, the structures of cleomiscosins A, B and C, three new coumarino-lignoids isolated from the seeds of Cleome viscosa Linne, were established as 1a, 2a and 1f irrespectively, on the basis of spectral and chemical evidence.
98 citations
TL;DR: This study suggests that calcium plays an imporatnt role in nitrogen fixation, nickel seems to have some role in regulating nitrogenase activity, and carbon fixation is a more sensitive parameter than growth and nitrogensase in evaluating metal toxicity.
Abstract: The effects of different concentrations of nickel (2.1, 4.2, 5.04μM) and silver (0.013, 0.026, 0.052μM) on survival, growth, carbon fixation and acetylene reduction of Nostoc muscorum has been studied. All concentrations of the heavy metals except 2.1μM Ni were inhibitory. At 2.1μM, nickel chloride stimulated carbon fixation and nitrogenase activity. Silver seems to be much more toxic than nickel because concentrations as low as 0.026μM silver chloride inhibited approximately 90% of the carbon fixation. EDTA protected carbon fixation and calcium ameliorated the nitrogenase activity in the test alga. However, none of these ameliorative agents were so effective against silver toxicity. This study suggests that (i) calcium plays an imporatnt role in nitrogen fixation, (ii) like hydrogen production and uptake hydrogenase, nickel seems to have some role in regulating nitrogenase activity, and (iii) carbon fixation is a more sensitive parameter than growth and nitrogensase in evaluating metal toxicity.
91 citations
TL;DR: The phenology of tree components of natural forests occurring between 350 and 2150 m in Kumaun Himalaya is descibed and for most species concentrated leafdrop and simultaneous leafing occurred during the warm-dry period of the year.
Abstract: The phenology of tree components of natural forests occurring between 350 and 2150 m in Kumaun Himalaya is descibed. All forests had more evergreen than deciduous taxa. The degree of evergreenness increased with increasing elevation and decreasing summer dryness. For most species (including all dominants) concentrated leafdrop and simultaneous leafing occurred during the warm-dry period of the year. About half of the species showed multiple leafing. All species had a sharp flowering peak in April. Wet-season flowering was rare. Most of the species flowered synchronously. In the sal- (Shorea robusta) and pine (Pinus roxburghii) forests a single peak of fruit maturation occurred in summer, while in other forests there also was a secondary peak in autumn.
87 citations
TL;DR: Comparisons of responses of 25 patients diagnosed as having anxiety neuroses showed differences in responses from the depressed patients and normal persons.
Abstract: 25 depressed patients recognized a sad face with more errors than 25 normal persons and labeled other expressions as sadness when affective content was not recognized. Correct recognitions for 6 affects were related to the portion of the face depicted. Comparisons of responses of 25 patients diagnosed as having anxiety neuroses showed differences in responses from the depressed patients and normal persons.
75 citations
TL;DR: In a controlled growth chamber experiment, the authors examined the aboveground-belowground, labile to structural tissue, and plant to soil dynamics of carbon to formulate a 14C dilution technique for potential successful application in the field and to quantify sources of error in production estimates.
Abstract: Estimates of belowground net primary production (BNP) obtained by using traditional soil core harvest data are subject to a variety of potentially serious errors. In a controlled growth chamber experiment, we examined the aboveground-belowground, labile to structural tissue, and plant to soil dynamics of carbon to formulate a14C dilution technique for potential successful application in the field and to quantify sources of error in production estimates. Despite the fact that the majority of net14C movement between above- and belowground plant parts occurred between the initial labeling and day 5, significant quantities of14C were incorporated into cell-wall tissue throughout the growing period. The rate of this increase at late sampling dates was greater for roots than for shoots. Total loss of assimilated14C was 47% in wheat and 28% in blue grama. Exudation and sloughing in wheat and blue grama, respectively, was 15 and 6% of total uptake and 22 and 8% of total plant production. When root production estimates by14C dilution were corrected for the quantities of labile14C incorporated into structural carbon between two sampling dates, good agreement with actual production was found. The error associated with these estimates was ±2% compared with a range of −119 to −57% for the uncorrected estimates. Our results suggest that this technique has potential field application if sampling is performed the year after labelling. Sources of errors in harvest versus14C dilution estimates of BNP are discussed.
73 citations
TL;DR: The roots of Haemanthus kalbreyeri contain a new phenanthridone alkaloid, k albretorine, and a new glucosyloxy alkaloids, kalbreclasine, which caused significant mitogenic activation of splenic lymphocytes characteristic of immuno stimulants.
64 citations
TL;DR: In this paper, two new acyl steryl glycosides, sitoindoside-III and sitoenide-IV, have been isolated from peeled fruits of Musa paradisiaca (banana, vegetable variety).
TL;DR: In this article, a numerical solution to the problem of thermal elastohydrodynamic lubrication of line contacts was obtained by using a finite difference formulation, which consists of simultaneous solution of the thermal Reynolds equation, the elasticity equation, and the energy equation subject to appropriate boundary conditions.
Abstract: A numerical solution to the problem of thermal elastohydrodynamic lubrication of line contacts was obtained by using a finite difference formulation. The solution procedure consists of simultaneous solution of the thermal Reynolds equation, the elasticity equation, and the energy equation subject to appropriate boundary conditions. Pressure distribution, film shape, and temperature distribution were obtained for fully flooded conjunctions, a paraffinic lubricant, and various dimensionless speed parameters while the dimensionless load and materials parameters were held constant. Reduction in the minimum film thickness due to thermal effects (as a ratio of thermal to isothermal minimum film thickness) is given by a simple formula as a function of the thermal loading parameter Q: H(min)/H(min,I) = 10/10+ Q(0.4). Plots of pressure distribution, film shape, temperature distribution, and flow are shown for some representative cases.
TL;DR: Cd2+ uptake rates in the cyanobacterium Anacystis nidulans IU 625 (ATCC 27144) were found to be concentration-dependent, and among the sythetic complexans, EDTA inhibited metal uptake, while citrate favored the process.
Abstract: Cd2+ uptake rates in the cyanobacterium Anacystis nidulans IU 625 (ATCC 27144) were found to be concentration-dependent. While Ca2+ and Zn2+ showed competitive inhibition, Hg2+ enhanced Cd2+ uptake. The pH values optimal for growth of the organism (pH 8.5) resulted in more Cd2+ uptake than low (pH 6.5) or high pH (10.0) conditions. Dithiol (dithiothreitol) proved more effective in lessening Cd2+ uptake than monothiol (mercaptoethanol). The test organism suspended in spent medium showed negligible Cd2+ uptake. Among the sythetic complexans, EDTA inhibited metal uptake, while citrate favored the process. There was more Cd2+ uptake by dense cultures, but the specific rate expressed per unit protein was less.
TL;DR: In this article, the synthesis, structural characteristics, hydrogen absorption behavior and electrical resistivity variation with hydrogenation in thin films of rare earth metal pentanickelides was investigated. But the results of the experiments were limited to the case where the synthesis of the rare earth intermetallics were done by suitable solid state interdiffusion and homogenization.
TL;DR: In this article, scale-dependent effects on the conductivity of disordered metallic systems are discussed to lowest order in the inverse diffusion tensor and in the interaction, showing that the scaling function and critical behavior near the localization transition are unaffected by anisotropy.
Abstract: Scale-dependent effects on the conductivity of anisotropic disordered metallic systems are discussed to lowest order in the inverse diffusion tensor ${D}_{\ensuremath{\mu}\ensuremath{
u}}^{\mathrm{\ensuremath{-}}1}$ and in the interaction. An eigenfunction expansion for anisotropic scattering and many-body perturbation theory are used to show that, in two dimensions, the fractional-scale-dependent conductivity is independent of direction. One consequence is that the scaling function and critical behavior near the localization transition are unaffected by anisotropy. Comparison with experimental results, and mapping onto a field theory, are briefly discussed.
TL;DR: In this article, metal(II) complexes of N-(thiophene-2-carboxamido)salicylaldimine (H2TCS) of types M(HTCS)-2Cl2 [M = Ni, Cu, Zn, Co, Ni and Zn] have been prepared and different modes of chelation of the ligand and the stereochemistry of the complexes are discussed.
TL;DR: In this paper, the effect of silicon in solid solution and in the form of suicides has been studied on the tensile properties and fracture behavior of alloy Ti-6Al-5Zr-0.25Si (alloy 685).
Abstract: The effect of silicon in solid solution and in the form of suicides has been studied on the tensile properties and fracture behavior of alloy Ti-6Al-5Zr-0.5Mo-0.25Si (alloy 685). The heat treatment to hold silicon in solid solution consists of solutionizing at 1323 K for 0.5 hour under vacuum (∼10-5 MPa), followed by water quenching, and the treatment to precipitate suicides involves subsequent aging of the solutionized and water quenched specimens at 1073 K for 24 hours. There is only marginal effect of the aging treatment on strength values; however, the ductility parameters are found to be drastically reduced. There are marked differences in the fracture behavior of the alloy in the as-quenched and the quenched and aged conditions. While the fracture surface of the unaged specimen shows characteristic dimples, there is a large number of facets on the fracture surface of the aged specimen. The facets in the central region are relatively smaller in size than those in the peripheral zone. The central facets show fluted features at higher magnifications; however, the peripheral facets are usually featureless. The faceted fracture in the aged condition is attributed to enhanced tendency for heterogeneous planar slip. The fracture characteristics correlate with the observed differences in the ductility in the two conditions.
TL;DR: Stem segments of adult plants of Ficus religiosa L. cultured on MS medium containing 1.0 mg/l 2,4-D produced callus and shoots regenerated when the induced calli were transferred to medium supplemented with 0.05 to 2.0mg/l BAP.
Abstract: Stem segments of adult plants of Ficus religiosa L. cultured on MS medium containing 1.0 mg/l 2,4-D produced callus. Shoots were regenerated when the induced calli were transferred to medium supplemented with 0.05 to 2.0 mg/l BAP. Callus derived shoots produced roots and developed into plantlets when transferred to medium supplemented with 1.0 mg/l NAA.
TL;DR: In most of the unsuccessful combinations, although the pollen germinated on the receiving stigmas, the pollen tube growth was inhibited inside the stigma or in the stylar tissue.
Abstract: Crossability of two cultivars of Cajanus cajan, eight species of Atylosia and one of Rhynchosia was investigated. Of the 73 combinations attempted, success was achieved in 12 cases. C. cajan crossed successfully with A. albicans, A. cajanifolia, A. lineata, A. scarabaeoides, and A. trinervia. Within the genus Atylosia, A. lineata crossed with A. albicans and A. scarabaeoides, and A. scarabaeoides with A. sericea. Three species
University of Rhode Island1, Flinders University2, Duke University3, University of Hawaii at Hilo4, United States Geological Survey5, Open University6, Marathon Oil7, Goethe University Frankfurt8, Ocean Drilling Program9, University of Waikato10, Banaras Hindu University11, University of Kiel12, University of Toyama13
TL;DR: In this paper, the late Eocene-early Oligocene (42-35 Myr) sediments cored at two DSDP sites in the south-west Pacific contain evidence of a pronounced increase in local volcanic activity, particularly in close association with the Eocene−Oligocene boundary.
Abstract: Late Eocene-early Oligocene (42–35 Myr) sediments cored at two DSDP sites in the south-west Pacific contain evidence of a pronounced increase in local volcanic activity, particularly in close association with the Eocene–Oligocene boundary. This pulse of volcanism is coeval with that in New Zealand and resulted from the development of an Indo- Australian / Pacific Plate boundary through the region during the late Eocene. The late Eocene / earliest Oligocene was marked by widespread volcanism and tectonism throughout the Pacific and elsewhere, and by one of the most important episodes of Cenozoic climatic cooling.
TL;DR: Two new types of alkaloidal conjugates were isolated from the fruits of Crinum asiaticum and an acylglucosyloxy derivative, named lycoriside and palmilycorine, were established on the basis of chemical transformation and comprehensive spectral evidence.
TL;DR: A new optically active flavan aglucone, 7-hydroxy-3-4-methylenedioxyflavan, and its 7glucoside have been isolated from the bulbs of Zephyranthes flava, collected at flowering.
TL;DR: An estimate of verbosity derived from a 2-min.
Abstract: An estimate of verbosity derived from a 2-min. free response to photographs depicting facial affect was examined in a 2 (depressed-control) × 3 (happy-sad-fear) × 2 (red-blue) factorial design. 30 ...
TL;DR: (-)-epicatechin did not have any effect on central nervous system of rats and mice, but had shown both positive chronotropic and inotropic effects on frog hearts, the effect of which is blocked by propranolol.
Abstract: (-)-Epicatechin has been isolated from the bark of PTEROCARPUS MARSUPIUM Roxb (Leguminosae). This flavonoid compound was tested for its activity on central nervous system, isolated frog heart preparations and blood sugar levels of rats. Preliminary acute toxicity studies were also carried out. It was observed that (-)-epicatechin did not have any effect on central nervous system of rats and mice, (-)-epicatechin had shown both positive chronotropic and inotropic effects on frog hearts, the effect of which is blocked by propranolol. The compound in higher doses caused hyperglycemia in rats and this effect is also blocked by propranolol, showing adrenergic type of activity. (-)-Epicatechin was found to have no untoward effect even in higher doses.
TL;DR: In this paper, a numerical solution for the effects of free-convection currents of a viscous fluid through a porous medium bounded by a vertical moving infinite vertical plate is considered, when the flow is unsteady.
Abstract: A numerical solution for the effects of the free-convection currents of a viscous fluid through a porous medium bounded by a vertical moving infinite vertical plate is considered, when the flow is unsteady. The graphs of velocity profiles for different values of permeability parameter of the porous medium and the Grashof number are discussed.
TL;DR: The polarized Raman spectrum of p -trifluoromethyl aniline was recorded on a Jobin Yvon Ramanor HG.2S spectrometer equipped with an argon-ion laser.