25,601 research outputs found

    Measuring thermodynamic length

    Get PDF
    Thermodynamic length is a metric distance between equilibrium thermodynamic states. Among other interesting properties, this metric asymptotically bounds the dissipation induced by a finite time transformation of a thermodynamic system. It is also connected to the Jensen-Shannon divergence, Fisher information and Rao's entropy differential metric. Therefore, thermodynamic length is of central interest in understanding matter out-of-equilibrium. In this paper, we will consider how to define thermodynamic length for a small system described by equilibrium statistical mechanics and how to measure thermodynamic length within a computer simulation. Surprisingly, Bennett's classic acceptance ratio method for measuring free energy differences also measures thermodynamic length.Comment: 4 pages; Typos correcte

    Bringing E-Government into the Classroom: A Case of E-Commerce Education

    Get PDF
    The paper discusses a novel educational initiative in e-commerce pedagogy where students work on an e-government project. The paper describes a two-semester joint e-government project conducted by the town of Amherst, NY, and the State University of New York at Buffalo. During the first semester, students in a graduate e-commerce course in the School of Management were instructed to identify and analyze management issues valuable for small or middle size local government. In the second semester graduate students from the Department of Computer Science and Engineering designed and implemented prototypes of three e-government portals: an on-line action site for governmental procurement (E-Procurement), a portal for reservation of community recreation facilities (E-Recreation), and a portal for online dog registration (E-DogRegistration) combining a central registry of dog owners with distributed veterinarian databases. The objective of this initiative is twofold. First, it saves the local government resources by eliminating duplication of services and by using students as developers. Second, it provides students with real life hands-on experience. The paper discusses both the technical issues involved in the implementation of the project, and the management issues that need to be taken into account to enhance the e-commerce experience for the ordinary citizen and local governments

    Solid-state metathesis reactions under pressure: A rapid route to crystalline gallium nitride

    Get PDF
    High pressure chemistry has traditionally involved applying pressure and increasing temperature until conditions become thermodynamically favorable for phase transitions or reactions to occur. Here, high pressure alone is used as a starting point for carrying out rapid, self-propagating metathesis reactions. By initiating chemical reactions under pressure, crystalline phases, such as gallium nitride, can be synthesized which are inaccessible when initiated from ambient conditions. The single-phase gallium nitride made by metathesis reactions under pressure displays significant photoluminescence intensity in the blue/ultraviolet region. The absence of size or surface-state effects in the photoluminescence spectra show that the crystallites are of micron dimensions. The narrow lines of the x-ray diffraction patterns and scanning electron microscopy confirm this conclusion. Brightly luminescent thin films can be readily grown using pulsed laser deposition

    On the origin of the various types of radio emission in GRS 1915+105

    Full text link
    We investigate the association between the radio ``plateau'' states and the large superluminal flares in GRS 1915+105 and propose a qualitative scenario to explain this association. We identify several candidate superluminal flare events from available monitoring data on this source and analyze the contemporaneous RXTE pointed observations. We detect a strong correlation between the average X-ray flux during the ``plateau'' state and the total energy emitted in radio during the subsequent radio flare. We find that the sequence of events is similar for all large radio flares with a fast rise and exponential decay morphology. Based on these results, we propose a qualitative scenario in which the separating ejecta during the superluminal flares are observed due to the interaction of the matter blob ejected during the X-ray soft dips, with the steady jet already established during the ``plateau'' state. This picture can explain all types of radio emission observed from this source in terms of its X-ray emission characteristics.Comment: Corrected typo in the author names, contents unchanged, accepted in Ap

    Coulomb Interactions and Nanoscale Electronic Inhomogeneities in Manganites

    Get PDF
    We address the issue of endemic electronic inhomogeneities in manganites using extensive simulations on a new model with Coulomb interactions amongst two electronic fluids, one localized (polaronic), the other extended (band-like), and dopant ions. The long range Coulomb interactions frustrate phase separation induced by the strong on site repulsion between the fluids. A single quantum phase ensues which is intrinsically and strongly inhomogeneous at a nano-scale, but homogeneous on meso-scales, with many characteristics (including colossal responses)that agree with experiments. This, we argue, is the origin of nanoscale inhomogeneities in manganites, rather than phase competition and disorder related effects as often proposed.Comment: 4 pages, 3 figure

    New species of the parasites of the Rhodes - grass scale from the Indian union

    Get PDF
    This article does not have an abstract

    Inelastic Neutron scattering in CeSi_{2-x}Ga_x ferromagnetic Kondo lattice compounds

    Full text link
    Inelastic neutron scattering investigation on ferromagnetic Kondo lattice compounds belonging to CeSi_{2-x}Ga_{x}, x = 0.7, 1.0 and 1.3, system is reported. The thermal evolution of the quasielastic response shows that the Kondo interactions dominate over the RKKY interactions with increase in Ga concentration from 0.7 to 1.3. This is related to the increase in k-f hybridization with increasing Ga concentration. The high energy response indicates the ground state to be split by crystal field in all three compounds. Using the experimental results we have calculated the crystal field parameters in all three compounds studied here.Comment: 12 Pages Revtex, 2 eps figures

    Heterosis and heterobeltiosis in bell pepper (Capsicum annuum var. grossum) for growth and yield parameters

    Get PDF
    The magnitude of heterosis over commercial check and better parent was estimated to identify best crosses for growth and yield traits in bell pepper. Experimental material included 21 F1 hybrids developed by crossing seven diverse parents in half diallel mating design. The findings revealed that Arka Mohini X CW308 showed best heterotic cross combinations, recorded significantly higher heterosis and high per se value over commercial check with respect to number of primary branches, number of secondary branches, plant height, days to 50% flowering, days to first harvest, fruit length, fruit width, number of lobes per fruit, number of fruits per plant and average fruit weight. The cross Arka Mohini X CW308 also showed high heterobeltiosis for traits like fruit length, number of fruits per plant, average fruit weight and average yield per plant. Hence, this hybrid with high per se value and heterosis can be utilized to obtain desirable segregates for development of superior genotype for improvement of horticultural traits in bell pepper

    Relations between structural distortions and transport properties in Nd0.5_{0.5}Ca0.5_{0.5}MnO3_3 strained thin films

    Full text link
    Strained thin films of charge/orbital ordered (CO/OO) Nd0.5Ca0.5MnO3Nd_{0.5}Ca_{0.5}MnO_3 (NCMO) with various thickness have grown on (100)-SrTiO3_3 and (100)-LaAlO3_3 substrates, by using the Pulsed Laser Deposition (PLD) technique. The thickness of the films influences drastically the transport properties. As the thickness decreases, the CO transition increases while at the same time the insulator-to-metal transition temperature decreases under application of a 7T magnetic field. Clear relationships between the structural distortions and the transport properties are established. They are explained on the basis of the elongation and the compression of the Mn-O-Mn and Mn-O bond angles and distances of the \QTR{it}{Pnma} structure, which modify the bandwidth and the Jahn-Teller distortion in these materialsComment: 11 pages, 6 figures. to be published in Journal Physics: Condensed Matte
    corecore