51,178 research outputs found

    Lightweight reflector assembly

    Get PDF
    An inexpensive, lightweight reflective assembly member having good optical quality and particularly adaptable to accommodating temperature variations without providing destructive thermal stresses and reflective slope errors is described. The reflective assembly consists of a thin sheet of glass with appropriate reflective coating and a cellular glass block substrate bonded together. The method of fabrication includes abrading the cellular substrate with an abrasive master die to form an appropriate concave surface. An adhesive is applied to the abraded surface and a lamina reflective surface is placed under a uniform pressure to conform the reflective surface onto the desired abraded surface of the substrate

    Dietary Uncoupling of Gut Microbiota and Energy Harvesting from Obesity and Glucose Tolerance in Mice

    Get PDF
    The authors gratefully acknowledge Doctoral Training Partnership funding from the BBSRC (M.J.D.) and funding from the Scottish Government (P.J.M., A.W.R., and A.W.W.). We also thank the Centre for Genome-Enabled Biology and Medicine for help with next-generation sequencing and Karen Garden and the Rowett’s Analytical Services for SCFA analysis. SUPPLEMENTAL INFORMATION Supplemental Information includes four figures and two tables and can be found with this article online at https://doi.org/10.1016/j.celrep.2017.10.056.Peer reviewedPublisher PD

    Thermal protection of reentry vehicles by actively cooled nosetips

    Get PDF
    Analytical modeling efforts and clear-air ground test results of a transportation-cooled nosetips (TCNT) design are presented. The discrete water injection platelet TCNT described was conceived and created to achieve the performance requirements for severe reentry vehicle trajectories. Thermal performance computer modeling techniques, combing both local heat blockage and boundary layer recovery enthalpy reduction are outlined

    Ground effects on Loran-C signals

    Get PDF
    In conjunction with the test and evaluation of the position fixing capabilities of the Army Manpack Loran Receiver AN/PSN-6, an extensive series of time difference and signal amplitude measurements were made within a 100 km map grid square encompassing Fort Monmouth, New Jersey. The test location is within the coverage area of the East Coast Loran-C Chain. The data were used to develop a simple smooth-earth model for the test area as well as to estimate the magnitude and distributions of deviations from this model. Local propagation processes associated with topographic features and the grid of overhead wires in the test area are shown to contribute to the deviations from the model

    Protective telescoping shield for solar concentrator

    Get PDF
    An apparatus is described for use with a solar concentrator such as a parabolic dish which concentrates sunlight onto a small opening of a solar receiver, for protecting the receiver in the event of a system failure that could cause concentrated sunlight to damage the receiver. The protective apparatus includes a structure which can be moved to a stowed position where it does not block sunlight, to a deployed position. In this position, the structure forms a tube which substantially completely surrounds an axis connecting the receiver opening to the center of the concentrator at locations between the receiver and the concentrator

    Investigation of waste products from Esparto paper mills: with a view to their economic utilisation

    Get PDF
    Papermaking is an art which has descended to us from the ancient civilisations, assuming greater importance with the passing years, until today, although materials and methods are entirely different, it ranks as one of our most important industries. Cellulosic fibre or "pulp" forms the basic material in the manufacture of paper and huge quantities are required annually. This fibrous pulp can be obtained from a great variety of raw materials, derived from the vegetable kingdom, but,from economic and other reasons, the commercial selection is restricted to certain species of wood, straw, esparto grass and linen and cotton rags. Except in the purely mechanical process of grinding down wood to prepare an inferior pulp for common newsprint papers, etc., the fibrous constituents of the various raw materials are separated from the organic encrustants by boiling out the latter, under regulated conditions of heat and pressure, with some suitable chemical. In America and on the continent, where wood is the chief raw material employed for the manufacture of pulp, various processes are in vogue, the choice of process being subservient to the class of wood being treated by the mill, and, of course, the grasses of paper for which the pulp is intended.In this country, however, where there is no wood pulp industry, and little, if any, preparation of fibre from straw, the soda boiling process is the only one in operation, the raw materials being esparto grass, rags, textile and rope wastes.In all of the processes for the preparation of pulp, and in many for its subsequent manufacture into paper, tremendous quantities of waste materials are produced, and the desire to find some commercial use for them, or obtain valuable substances from them, has engaged the attention of numerous investigators for years. A vast amount of work has been accomplished and although the greater part has never passed beyond the experimental stage, manufacturers have been able to avail themselves of some of the uses proposed, and several of the large continental concerns are profitably doing so.Unfortunately, the bulk of this research work has been carried out abroad and relates principally to the problems in the processes employing the sulphite, soda, and soda-sulphate methods of preparing fibre from wood and straw.Certainly, several papers have been published and numerous patents taken out in this country, dealing with problems found in the esparto paper mills, but they have had little or no success, or even attention, partly because they have failed to pass a commercial test, partly because many of them have only dealt with some particular waste material in view of local conditions, but principally because it is the general belief that such subsidiary processes would be of little value, the units being so small when compared with the continental concerns.While there is a certain amount of truth in this, it is also true that the problem has not had the attention that might have been given to it, and certainly, no paper dealing with all of the waste products in detail has yet appeared. The present work, therefore, was commenced with the object of making a detailed investigation of the various wastes produced and to discover, if possible, some application, or applications, which would have more hope of success than these previously suggested.It should be borne in mind, that in work of this nature, while purely chemical research often leads to improvements, and even, from time to time, creates new side lines, advances may also be effected by the application of knowledge which has already been placed on record. Many previously waste products have been utilised, and a number of originally crude processes have been developed, by the application of chemical knowledge which has been gained before. The solution of a problem, therefore, may not depend upon the prosecution of entirely new investigations.It should be added, that in keeping with the general character of the present work and the variety of wastes to be examined, any particular line of investigation has mot been prolonged to the detriment of others, but discontinued at a point from where it could be observed, whether or not, future work might be profitable.The work has been divided into sections, each section being occupied with the examination and utilisation of a waste material, and placed in the order in which the wastes appear in the process of manufacturing the paper. While it is not proposed to utilise much space in describing the actual manufacture of the paper, sufficient details are given to enable one to understand the nature and occurrence of the various wastes.The samples of material analysed and process data, except when otherwise stated, were obtained for the present work from mills situated in the near vicinity of Edinburgh. For private reasons these mills have been given letters instead of their original names

    Tuning grid storage resources for LHC data analysis

    Get PDF
    Grid Storage Resource Management (SRM) and local file-system solutions are facing significant challenges to support efficient analysis of the data now being produced at the Large Hadron Collider (LHC). We compare the performance of different storage technologies at UK grid sites examining the effects of tuning and recent improvements in the I/O patterns of experiment software. Results are presented for both live production systems and technologies not currently in widespread use. Performance is studied using tests, including real LHC data analysis, which can be used to aid sites in deploying or optimising their storage configuration
    corecore