15,368 research outputs found

    Method for retarding dye fading during archival storage of developed color photographic film

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    Dye fading during archival storage of developed color photographic film is retarded by placing the film in a sealed, opaque vault, introducing a dry, pressurized inert gas into the vault while the latter is vented, and sealing the vault after the air within the vault has been purged and replaced by the inert gas. Preferably, the gas is nitrogen; and the vault is stored at a temperature below room temperature to preserve the color photographic emulsions on the film contained within the vault. For short-term storage, sodium thiocyanate pads charged with water are placed within the vault. For long term storage, the interior of the vault is kept at a low relative humidity

    Latching mechanism Patent

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    Latch for fastening spacecraft docking ring

    NASA Contributions to Development of Special-Purpose Thermocouples. A Survey

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    The thermocouple has been used for measuring temperatures for more than a century, but new materials, probe designs, and techniques are continually being developed. Numerous contributions have been made by the National Aeronautics and Space Administration and its contractors in the aerospace program. These contributions have been collected by Midwest Research Institute and reported in this publication to enable American industrial engineers to study them and adapt them to their own problem areas. Potential applications are suggested to stimulate ideas on how these contributions can be used

    Varying Constants in Brane World Scenarios

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    Higher-dimensional theories imply that some constants, such as the gravitational constant and the strength of the gauge-couplings, are not fundamental constants. Instead they are related to the sizes of the extra--dimensional space, which are moduli fields in the four--dimensional effective theory. We study the cosmological evolution of the moduli fields appearing in brane world scenarios and discuss the implications for varying constants.Comment: 5 pages, LaTeX, 5 figures; based on a talk given by C. van de Bruck at JENAM 2002, Porto; typos correcte

    CMB Anisotropies in the Presence of Extra Dimensions

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    We discuss the effect of the time evolution of extra dimensions on CMB anisotropies and large-scale structure formation. We study the impact of scalar fields in a low-energy effective description of a general class of brane world models on the temperature anisotropy power spectrum. We show that when the coupling between these scalar fields and matter evolves over cosmological timescales, current observations of the CMB anisotropies can constrain primordial values of the fields in a manner complementary to local, late-time tests of gravity. We also present the effect of these fields on the polarization anisotropy spectra and the growth of large-scale structure, showing that future CMB observations will constrain theories of the Universe involving extra dimensions even further.Comment: 17 pages, 15 figure

    Opportunities and Constraints for Cooperation between International Organisations

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    This paper provides an examination of opportunities for and constraints on cooperation between international organisations, which is an increasingly important form of governance. Two case studies are presented which have relevance to the issues of intellectual property and climate change. These represent an established governance area (genetic resources) and an emerging area (biofuels)

    Optimum transportation systems to serve the mineral industry north of the Yukon basin in Alaska

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    In 1972 the U. S . Bureau of Mines awarded a grant (No. G 01 22096) to the Mineral Industry Research Laboratory, University of Alaska, for a research project to determine optimum transportation systems to serve the mineral industry north of the Yukon River basin in Alaska. The study was conducted during the period May 1 - November 1, 1972. The study assesses the mineral potential of the region and selects two copper deposits: a known one at Bornite, and a potential one on the upper Koyukuk River. Two possible mining sites within the extensive coal bearing region north of the Brooks Range are also selected. A computer model was developed to perform an economic analysis of technically feasible transportation modes and routes from these four sites to Alaskan ports from which minerals could be shipped to markets. Transport modes considered are highway, rail, cargo aircraft, river barge, winter haul road and air cushion vehicles (A.C.V.). The computer program calculates the present worth of tax benefits from mining and transportation and revenues based on the value of minerals at the port, as well as the auxillary benefits derived from the anticipated use of the routes by the tourist industry. Annual and fixed costs of mining and transportation of minerals are calculated, and benefit-cost ratios determined for each combination of routes and modes serving the four mineral sites. The study concludes that the best systems in terms of a high benefit-cost ratio are those utilizing a minimum of new construction of conventional highways or railroads. The optimum system as derived from this study is one linking together existing transportation systems with aircraft or A.C.V. These modes are feasible only for the shipment of a high value product, namely blister copper produced by a smelter at the mining site, Of the several alternatives considered for the shipment of coal, only a slurry pipeline to an as yet undeveloped port on the Arctic coast showed significant promise. The study recommends that: 1. More government support should be given to mineral exploration in Alaska. 2. Potential mineral industry development should be considered in transportation planning at state and federal levels. 3. Additional research pertinent to mining and processing of minerals in the North should be conducted, and the feasibility of smelting minerals within Alaska explored. 4. Alternatives for providing power to Northwestern Alaska should be investigated

    Underperforming policy networks : the biopesticides network in the United Kingdom

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    Loosely integrated and incomplete policy networks have been neglected in the literature. They are important to consider in terms of understanding network underperformance. The effective delivery and formulation of policy requires networks that are not incomplete or underperforming. The biopesticides policy network in the United Kingdom is considered and its components identified with an emphasis on the lack of integration of retailers and environmental groups. The nature of the network constrains the actions of its agents and frustrates the achievement of policy goals. A study of this relatively immature policy network also allows for a focus on network formation. The state, via an external central government department, has been a key factor in the development of the network. Therefore, it is important to incorporate such factors more systematically into understandings of network formation. Feedback efforts from policy have increased interactions between productionist actors but the sphere of consumption remains insufficiently articulated
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