18 resultados para Rothschild, Nathan Mayer vonRothschild, Nathan Mayer vonNathan MayerRothschildvon
em Indian Institute of Science - Bangalore - Índia
Resumo:
We present an analysis of the breakdown of the most probable approximation to the Mayer cluster size distribution for clusters of size comparable to the size of the system. This failure is illustrated by considering an ideal Bose gas for which exact volume dependent reducible cluster integrals are available.
Resumo:
The sputter deposition of YBa2Cu3O7-x in a de-diode was performed in pure oxygen medium and an optical spectroscopic study of the resultant discharge revealed strong emissions from both metal atoms and oxygen ions. Emission intensities were studied in pressure range from 0.5 to 3 mbar, with substrate temperatures from 150 to 850 degrees C. Raising the substrate temperature to 850 degrees C increased the number of positive ions and excited neutral atoms. Raising the pressure decreased the emission intensities of excited neutral and ionic species. The results have been compared with those obtained from Langmuir probe measurements. The rise in emission intensities of excited neutrals and ions with temperature suggested the possibility of chemically enhanced physical sputtering of YBa2Cu3O7-x. The effect of process conditions on film composition and quality is also discussed.
Resumo:
The ultimate flexural strength behavior of isolated square tapered and beam-slab reinforced footings are presented. Yield line solutions are developed for generalized contact pressure distributions and the influence of taper, beam size, fillet size, negative moment capacity, and contact pressure distribution on the collapse load is brought out. In beam-slab footings the optimum relative beam capacity required to make the beam rigid is indicated. Results of experimental investigations on footings resting on sand reveal that tapered (with isotropic as well as with alternative reinforcement patterns) and beam-slab footings exhibit superior structural behavior in terms of normalized first crack load, collapse load, relative rigidity, relative efficiency, and failure mechanism.
Resumo:
Isothermal titration calorimetry measurements of the binding of 2′-fucosyllactose, lactose, N-acetyllactosamine, galactopyranose, 2-acetamido-2-deoxygalactopyranoside, methyl α-N-dansylgalactosaminide (Me-α-DNS-GalN), methyl α-D-galactopyranoside, methyl β-D-galactopyranoside, and fucose to Erythrina corallodendron lectin (ECorL), a dimer with one binding site per subunit, were performed at 283-286 and 297-299 K. The site binding enthalpies, ΔHb, with the exception of Me-α-DNS-GalN, are the same at both temperatures and range from −47.1 ± 1.0 kJ mol−1 for N-acetyllactosamine to −4.4 ± 0.3 kJ mol−1 for fucose, and the site binding constants range from 3.82 ± 0.9 × 105 M−1 for Me-α-DNS-GalN at 283.2 K to 0.46 ± 0.05 × 103 M−1 for fucose at 297.2 K. The binding reactions are mainly enthalpically driven except for fucose and exhibit enthalpy-entropy compensation. The binding enthalpies of the disaccharides are about twice the binding enthalpies of the monosaccharides in contrast to concanavalin A where the binding enthalpies do not double for the disaccharides. Differential scanning calorimetry measurements show that denaturation of the ECorL dimer results in dissociation into its monomer subunits. The binding constants from the increase in denaturation temperature of ECorL in the presence of saccharides are in agreement with values from isothermal titration calorimetry results. The thermal denaturation of ECorL occurs around 333 K, well below the 344-360 K denaturation temperature of other legume lectins of similar size and tertiary structure, undoubtedly due to the difference in its quaternary structure relative to other legume lectins. This is also apparent from the independent unfolding of its two domains.
Resumo:
Provision of modern energy services for cooking (with gaseous fuels)and lighting (with electricity) is an essential component of any policy aiming to address health, education or welfare issues; yet it gets little attention from policy-makers. Secure, adequate, low-cost energy of quality and convenience is core to the delivery of these services. The present study analyses the energy consumption pattern of Indian domestic sector and examines the urban-rural divide and income energy linkage. A comprehensive analysis is done to estimate the cost for providing modern energy services to everyone by 2030. A public-private partnership-driven business model, with entrepreneurship at the core, is developed with institutional, financing and pricing mechanisms for diffusion of energy services. This approach, termed as EMPOWERS (entrepreneurship model for provision of wholesome energy-related basic services), if adopted, can facilitate large-scale dissemination of energy-efficient and renewable technologies like small-scale biogas/biofuel plants, and distributed power generation technologies to provide clean, safe, reliable and sustainable energy to rural households and urban poor. It is expected to integrate the processes of market transformation and entrepreneurship development involving government, NGOs, financial institutions and community groups as stakeholders. (C) 2009 Elsevier Ltd. All rights reserved.
Resumo:
Individuals in distress emit audible vocalizations to either warn or inform conspecifics. The Indian short-nosed fruit bat, Cynopterus sphinx, emits distress calls soon after becoming entangled in mist nets, which appear to attract conspecifics. Phase I of these distress calls is longer and louder, and includes a secondary peak, compared to phase II. Activity-dependent expression of egr-1 was examined in free-ranging C. sphinx following the emissions and responses to a distress call. We found that the level of expression of egr-1 was higher in bats that emitted a distress call, in adults that responded, and in pups than in silent bats. Up-regulated cDNA was amplified to identify the target gene (TOE1) of the protein Egr-1. The observed expression pattern Toe1 was similar to that of egr-1. These findings suggest that the neuronal activity related to recognition of a distress call and an auditory feedback mechanism induces the expression of Egr-1. Co-expression of egr-1 with Toe1 may play a role in initial triggering of the genetic mechanism that could be involved in the consolidation or stabilization of distress call memories.
Resumo:
The sympatrically occurring Indian short-nosed fruit bat Cynopterus sphinx and Indian flying fox Pteropus giganteus visit Madhuca latifolia (Sapotaceae), which offers fleshy corollas (approximate to 300 mg) to pollinating bats. The flowers are white, tiny and in dense fascicles The foraging activities of the two bat species were segregated in space and time. Cynopterus sphinx fed on resources at lower heights in the trees than P giganteus and its peak foraging activity occurred at 19 30 h, before that of P giganteus Foraging activities involved short searching flights followed by landing and removal of the corolla by mouth Cynopterus sphinx detached single corollas from fascicles and carried them to nearby feeding roosts, where it sucked the juice and spat out the Fibrous remains Pteropus giganteus landed on top of the trees and fed on the corollas in situ, its peak activity occurred at 20 30 11 This species glided and crawled between the branches and held the branches with claws and forearms when removing fleshy corollas with Its Mouth Both C sphinx and P giganteus consumed fleshy corollas with attached stamens and left the gynoecium intact Bagging experiments showed that fruit-set in bat-visited flowers was significantly higher (P < 0.001) than in self-pollinated flowers.
Resumo:
Commercialization efforts to diffuse sustainable energy technologies (SETs1) have so far remained as the biggest challenge in the field of renewable energy and energy efficiency. Limited success of diffusion through government driven pathways urges the need for market based approaches. This paper reviews the existing state of commercialization of SETs in the backdrop of the basic theory of technology diffusion. The different SETs in India are positioned in the technology diffusion map to reflect their slow state of commercialization. The dynamics of SET market is analysed to identify the issues, barriers and stakeholders in the process of SET commercialization. By upgrading the ‘potential adopters’ to ‘techno-entrepreneurs’, the study presents the mechanisms for adopting a private sector driven ‘business model’ approach for successful diffusion of SETs. This is expected to integrate the processes of market transformation and entrepreneurship development with innovative regulatory, marketing, financing, incentive and delivery mechanisms leading to SET commercialization.
Resumo:
The variety of electron diffraction patterns arising from the decagonal phase has been explored using a stereographic analysis for generating the important zone axes as intersection points corresponding to important relvectors. An indexing scheme employing a set of five vectors and an orthogonal vector has been followed. A systematic tilting from the decagonal axis to one of the twofold axes has been adopted to generate a set of experimental diffraction patterns corresponding to the expected patterns from the stereographic analysis with excellent agreement.
Resumo:
The structures of a PbO.SiO2 glass and melt have been studied using molecular dynamics simulation employing Born-Mayer-Huggins pair potentials. Various pair distribution functions are presented and discussed. Pb-Pb correlations persist in the melt, in agreement with experimental observations. The calculated and experimental radial distribution functions are compared.
Resumo:
Critical exponent of the electrical conductivity in the paracoherence region (gamma) of the high temperature superconductor YBa2Cu3O7-x (YBCO) has been estimated for high quality thin film on ZrO2 substrate prepared by high pressure oxygen sputtering. High energy ion irradiation was carried out using 100 MeV O-16(7+) ions at liquid nitrogen to see the effects of disorder on the value of the exponent. The critical exponent from a value of about 2 to 1.62 upon irradiation. Studies were also carried film to see the effect of ageing and annealing.
Resumo:
The principle of the conservation of bond orders during radical-exchange reactions is examined using Mayer's definition of bond orders. This simple intuitive approximation is not valid in a quantitative sense. Ab initio results reveal that free valences (or spin densities) develop on the migrating atom during reactions. For several examples of hydrogen-transfer reactions, the sum of the reaction coordinate bond orders in the transition state was found to be 0.92 +/- 0.04 instead of the theoretical 1.00 because free valences (or spin densities) develop on the migrating atom during reactions. It is shown that free valence is almost equal to the square of the spin density on the migrating hydrogen atom and the maxima in the free valence (or spin density) profiles coincide (or nearly coincide) with the saddle points in the corresponding energy profiles.
Resumo:
The kinetics of the processes in facing targets sputtering of multicomponent oxide films is presented. The novel configuration of the process exhibits an enhanced ionization efficiency. Discharge diagnostics performed using optical emission spectroscopy revealed strong dependence of plasma parameters on process conditions. Numerical simulation based on thermalization and diffusion of sputtered atoms has been performed to estimate the transport efficiency in off-axis mode. Composition, structure and epitaxial quality of YBa2Cu3O7-x films prepared was found to be strongly dependent on atomic flux ratios (of Cu/Y and Ba/Y) arriving at the substrate, resputtering effect and phase stability of YBa2Cu3O7-x These studies have been shown to be useful in understanding the complex processes that occur in sputtering of multicomponent films. (C) 1999 Elsevier Science S.A. All rights reserved.
Resumo:
Niche differentiation has been proposed as an explanation for rarity in species assemblages. To test this hypothesis requires quantifying the ecological similarity of species. This similarity can potentially be estimated by using phylogenetic relatedness. In this study, we predicted that if niche differentiation does explain the co-occurrence of rare and common species, then rare species should contribute greatly to the overall community phylogenetic diversity (PD), abundance will have phylogenetic signal, and common and rare species will be phylogenetically dissimilar. We tested these predictions by developing a novel method that integrates species rank abundance distributions with phylogenetic trees and trend analyses, to examine the relative contribution of individual species to the overall community PD. We then supplement this approach with analyses of phylogenetic signal in abundances and measures of phylogenetic similarity within and between rare and common species groups. We applied this analytical approach to 15 long-term temperate and tropical forest dynamics plots from around the world. We show that the niche differentiation hypothesis is supported in six of the nine gap-dominated forests but is rejected in the six disturbance-dominated and three gap-dominated forests. We also show that the three metrics utilized in this study each provide unique but corroborating information regarding the phylogenetic distribution of rarity in communities.