1,701,273 research outputs found

    Concept for passive system to control gas flow independently of temperature

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    Volumetric flow rate of gas is maintained at a constant value independent of temperature by passing the gas through a parallel or series combination of turbulent flow and laminar flow restrictors. By proper combination of restrictors, the flow rate may be automatically made to vary as an increasing or decreasing function of temperature

    c(2x2) Interface Alloys in Co/Cu Multilayers - Influence on Interlayer Exchange Coupling and GMR

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    The influence of a c(2x2) ordered interface alloy of 3d transition metals at the ferromagnet/nonmagnet interface on interlayer exchange coupling (IXC), the formation of quantum well states (QWS) and the phenomenon of Giant MagnetoResistance is investigated. We obtained a strong dependence of IXC on interface alloy formation. The GMR ratio is also strongly influenced. We found that Fe, Ni and Cu alloys at the interface enhance the GMR ratio for in-plane geometry by nearly a factor of 2.Comment: 14 pages, 5 figures, 1 table, subm. to PR

    Computer Simulation of Chute Flows of Granular Materials

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    The purpose of the present paper is to present results from computer simulations of the flow of granular materials down inclined chutes or channels and to compare the results of these calculations with existing experimental measurements of velocity, solid fraction and mass flow rate profiles

    Trade Openness and Economic Performance of ECOWAS Members - Reflections From Ghana And Nigeria.

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    Trade openness is believed to stimulate economic growth due to its influence in integrating world economies and generating better markets. The study examined the impact of trade openness on economic performance of ECOWASMembers focusing on Ghana and Nigeria (1975-2004).Data sourced from IFS and others, were analyzed employing ADF/PP stationarity, cointegration and vector error correction techniques. A unique long-run relationship between economic performance, trade openness, real government expenditure, labour force and real capital stock for both Ghana and Nigeria was established, while about 88.9"10 and 83.1"10 errors made in the previous period were found to be corrected in the current period for the respective countries. In addition, trade openness and real government expenditure impact positively the economies of Ghana and Nigeria. However, the effectswere higher in the former than the latter

    ICT AND NIGERIAN BANKS REFORMS: ANALYSIS OF ANTICIPATED IMPACTS IN SELECTED BANKS

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    Banking has become highly ICT based and due to its inter-sectoral link, it is reaping the benefits of technological revolution as evidenced by its application in most of its operations. The study carried out empirical analysis of the anticipated role ICT has in enhancing the operations of selected Nigerian banks in the light of current reforms. Primary data was employed, which was analyzed using cross-tabulations and regression technique built on the framework of technical progress. Factors such as bankers’ age, educational qualification, computer literacy and type of ICT gadgets, were found to influence banks’ degree of ICT usage, while ICT impacts significantly the speed of banking operations, productivity and profitability. The need for the banks to regularly train their workers, and procure quality ICT gadgets, which will enhance efficiency, etc, was stressed. This is crucial in the sector’s current reforms where attention is focused on the ability of banks to attract and retain customers, which is mainly feasible through efficient service delivery that depend, to a large extent, on the use of ICT

    FOREIGN CAPITAL AND AFRICA’S ECONOMIC PROGRESS: FACTS FROM NIGERIA AND SOUTH AFRICA

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    Foreign capital inflow is usually believed as a means of supplementing domestic capital. The paper examined the influence of foreign capital on Africa’s economic progress focusing on Nigeria and South Africa (1970-2004). Data sourced from IFS, CBN and others were analyzed with econometric techniques. Empirical facts from cointegration and Granger casualty tests are as follows: There is a long-run relationship between foreign capital and economic progress in South Africa but in Nigeria it is short-run oriented; Foreign capital Granger-causes economic progress in South Africa, while in Nigeria casualty runs on the reverse; a bi-directional causality exists between economic progress and domestic capital in South Africa, for Nigeria it is uni-directional running from domestic capital to economic progress; Labour force in both countries Granger-causes their economic progress. In the light of the above, foreign capital should be promoted in South Africa to enhance her economic progress while in Nigeria polices that can reduce the level of capital flight (e.g. dependable institutional framework etc) are essential for foreign capital to have long-run influence on her economic progress. The need for the countries to rely more on domestic capital is equally suggested as viable factors for their economic progress

    Reformulation of the LDA+U method for a local orbital basis

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    We present a new approach to the evaluation of the on-site repulsion energy U for use in the LDA+U method of Anisimov and collaborators. Our objectives are to make the method more firmly based, to concentrate primarily on ground state properties rather than spectra, and to test the method in cases where only modest changes in orbital occupations are expected, as well as for highly correlated materials. Because of these objectives, we employ a differential definition of U. We also define a matrix U, which we find is very dependent on the environment of the atom in question. The formulation is applied to evaluate U for transition metal monoxides from VO to NiO using a local orbital basis set. The resulting values of U are typically only 40-65% as large as values currently in use. We evaluate the U matrix for the e_g and t_{2g} subshells in paramagnetic FeO, and illustrate the very different charge response of the e_g and t_{2g} states. The sensitivity of the method to the choice of the d orbitals, and to the basis set in general, is discussed.Comment: 6 figure

    Globalisation, Governance and Economic Growth in West Africa: The Case of Cote D' Ivoire and Nigeria

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    Globalization conveys varying messages to its audience due to its trans-disciplinary nature, and the pattern of governance and socio-political atmosphere in a given economy can influence the e),.1entto which globalization is harnessed. The study examined the influence of globalization and governance on economic growth in West Africa, drawing empirical facts from Cote d'Ivoire and Nigeria. Data sourced from IFS and Polity IV for the period 1960-2004 were analyzed using parsimonious error correction model after Carrying out stationarity and cointegration tests. Whereas the measure of globalization was found to influence positively the economic growth of Cote d'Ivoire and Nigeria, the nature of governance and socio-political situations had negative effect. The study recommends that efforts are to be made by these countries to adapt technologies that suit local peculiarities via appropriate policies, in order to significantly partake of the opportunities that are in the globalizing world. The need for the nature of governance and socio-political ambiance to be investment friendly was also advocate

    Highly fluorinated polyurethanes

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    The reaction perfluorinated hydroxyl terminated polyether with diisocyanate to form polyurethane is discussed. Data are given on the resin's oxidation stability, chemical resistance, and low temperature flexibility

    Preparation of highly fluorinated polyurethanes

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    New polyurethanes, formed from a reaction of a prepolymer diol and a perfluorinated diisocyanate, are nonflammable and possess high corrosion resistance and good low temperature flexibility. Polymer hardness increases rapidly with increasing ratio of diisocaynate to diol, but its glass transition temperature is not adversely affected
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