6,156 research outputs found

    Process for purification of silicon

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    The purification of metallurgically pure silicon having a silicon content of more than 95% by weight is accomplished by leaching with an acidic solution which substantially does not attack silicon. A mechanical treatment leading to continuous particle size reduction of the granulated silicon to be purified is combined with the chemical purification step

    Si3N4 single-crystal nanowires grown from silicon micro and nanoparticles near the threshold of passive oxidation

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    A simple and most promising oxide-assisted catalyst-free method is used to prepare silicon nitride nanowires that give rise to high yield in a short time. After a brief analysis of the state of the art, we reveal the crucial role played by the oxygen partial pressure: when oxygen partial pressure is slightly below the threshold of passive oxidation, a high yield inhibiting the formation of any silica layer covering the nanowires occurs and thanks to the synthesis temperature one can control nanowire dimensions

    Digital Resources on the Web

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    Management innovation through industrial management research in the individual firm and its specific application to market opportunity assessment studies

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    In this Thesis the Researcher describes the work done in the course of an Industrial PhD. program with the University of Technology, Loughborough, Upon completion of a period of training, the Researcher joined an industrial firm with the view of investigating ways of Management Innovation in the practical environment. The Industrial PhD. scheme being a new concept, based on investigation of practical problems within industrial enterprises and this study being the first of its kind, greater emphasis has been laid on the description of the Research Environment, and the actions and reactions of the Researcher and the Medium. The study was carried out over a period of four years, one academic year of post-graduate, post-experience training at the University, followed by three years of industrial investigation. During the period of industrial investigation the Researcher was a full time employee of the "Co-operating Firm". The Research Environment is described in Part I of the Thesis. In his initial capacity with the Co-operating Firm, the Researcher could not put forth his plans on the strength of his own functional responsibilities, but merely as proposals from an employee of the Company. The organisational pattern of the Company did not cater for a central planning function. The Researcher studied the firm's requirements and devised a proposed program of work to provide an input to a Corporate Plan which was to follow. The Market Plan to be developed was intended to provide a focal point for the firm's Corporate Plan. Subsequent organisational changes within the firm, allowed the Researcher to reach a position where first he was given advisory responsibility for Market Planning, and finally direct functional responsibility for implementation. From the outset, the Researcher provided Management with specific surveys and investigations in defined areas of imminent interest to the Organisation, which were acknowledged as being useful although seldom implemented. The Researcher succeeded in demonstrating the need and the feasibility of greater use of Scientific Management in the firm, and his own capability in contributing in its implementation. The organisational changes which occurred, took cognizance of this development and gradually the Researcher's programme was incorporated in the Company's Corporate plan. The Researcher's work embraced, (a) The formulation of an overall Market Plan and (b) A specific topic of research within the overall Plan. Market Opportunity Assessment studies constituted the specific topic of research. The method developed provided a working tool needed in the implementation of the Market Plan. The Market Plan required applied research in two additional specific areas, (a) The development of a Linear Programme for Product Mix Optimisation and (b) An Input Output Matrix disaggregation for the Company's product lines, for Long Term forecasting purposes. (Continues...)

    Practical scheme for a light-induced gauge field in an atomic Bose gas

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    We propose a scheme to generate an Abelian gauge field in an atomic gas using two crossed laser beams. If the internal atomic state follows adiabatically the eigenstates of the atom-laser interaction, Berry's phase gives rise to a vector potential that can nucleate vortices in a Bose gas. The present scheme operates even for a large detuning with respect to the atomic resonance, making it applicable to alkali-metal atoms without significant heating due to spontaneous emission. We test the validity of the adiabatic approximation by integrating the set of coupled Gross-Pitaevskii equations associated with the various internal atomic states, and we show that the steady state of the interacting gas indeed exhibits a vortex lattice, as expected from the adiabatic gauge field.Comment: 4 pages, 3 figure

    Accuracy of predicting milk yield from alternative milk recording schemes

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    peer-reviewedThe effect of reducing the frequency of official milk recording and the number of recorded samples per test-day on the accuracy of predicting daily yield and cumulative 305-day yield was investigated. A control data set consisting of 58 210 primiparous cows with milk test-day records every 4 weeks was used to investigate the influence of reduced milk recording frequencies. The accuracy of prediction of daily yield with one milk sample per test-day was investigated using 41 874 testday records from 683 cows. Results show that five or more test-day records taken at 8-weekly intervals (A8) predicted 305-day yield with a high level of accuracy. Correlations between 305-day yield predicted from 4-weekly recording intervals (A4) and from 8-weekly intervals were 0.99, 0.98 and 0.98 for milk, fat and protein, respectively. The mean error in estimating 305-day yield from the A8 scheme was 6.8 kg (s.d. 191 kg) for milk yield, 0.3 kg (s.d. 10 kg) for fat yield, and −0.3 kg (s.d. 7 kg) for protein yield, compared with the A4 scheme. Milk yield and composition taken during either morning (AM) or evening (PM) milking predicted 24-h yield with a high degree of accuracy. Alternating between AM and PM sampling every 4 weeks predicted 305-day yield with a higher degree of accuracy than either all AM or all PM sampling. Alternate AM-PM recording every 4 weeks and AM + PM recording every 8 weeks produced very similar accuracies in predicting 305-day yield compared with the official AM + PM recording every 4 weeks

    How to improve drug dosing for patients with renal impairment in primary care - a cluster-randomized controlled trial

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    Background: Patients with chronic kidney disease (CKD) are at increased risk for inappropriate or potentially harmful prescribing. The aim of this study was to examine whether a multifaceted intervention including the use of a software programme for the estimation of creatinine clearance and recommendation of individual dosage requirements may improve correct dosage adjustment of relevant medications for patients with CKD in primary care. Methods: A cluster-randomized controlled trial was conducted between January and December 2007 in small primary care practices in Germany. Practices were randomly allocated to intervention or control groups. In each practice, we included patients with known CKD and elderly patients (>=70 years) suffering from hypertension. The practices in the intervention group received interactive training and were provided a software programme to assist with individual dose adjustment. The control group performed usual care. Data were collected at baseline and at 6 months. The outcome measures, analyzed across individual patients, included prescriptions exceeding recommended maximum daily doses, with the primary outcome being prescriptions exceeding recommended standard daily doses by 30% or more. Results: Data from 44 general practitioners and 404 patients are included. The intervention was effective in reducing prescriptions exceeding the maximum daily dose per patients, with a trend in reducing prescriptions exceeding the standard daily dose by more than 30%. Conclusions: A multifaceted intervention including the use of a software program effectively reduced inappropriately high doses of renally excreted medications in patients with CKD in the setting of small primary care practices

    Basic vision training manual

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    Basic vision training manua

    Nutritional Immunomodulation as an Approach to Decreasing the Negative Effects of Stress in Poultry Production

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    Stress can lead to changes in the immune response resulting in both increased and decreased resistance to opportunistic bacterial pathogens. Growth-promoting antibiotics have been a major tool in modulating hostpathogen interactions and limiting clinical and subclinical bacterial infection in confined animal production. Regulatory pressures to limit antibiotic use in poultry production and recent international marketing agreements that prohibit treating poultry with antibiotics have limited the disease-fighting tools available to poultry and livestock producers, particularly in Europe. There is a need to evaluate potential antibiotic alternatives to improve both production and disease resistance in high-intensity food animal production. Nutritional approaches to counteract the debilitating effects of stress and infection may provide producers with useful alternatives to antibiotics. Improving disease resistance in food animals, particularly in the absence of antibiotic treatment, is a key strategy in the effort to increase food safety. ARS research has demonstrated the efficacy of several nutritional immunomodulators, including vitamin D3 and yeast cell wall products, to protect against bacterial infection due to stress and challenge with opportunistic pathogens. These studies also provide an animal model for testing the efficacy of nutritional strategies that may affect the response to stress and related infection in humans
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