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发布日期:2019

发布机构:[International Atomic...

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This Safety Guide is applicable to the predisposal management of radioactive waste derived from the use of radioactive materials in medicine, industry, agriculture, research and education, including disused sealed radioactive sources. It focuses on waste generated at facilities such as hospitals and research centres, where radioactive waste is not usually generated in bulk quantities. It covers the managerial, administrative and technical issues associated with the safe management of radioactive waste, from its generation to its acceptance at a disposal facility or its release from regulatory control.

作者:Valder, Joshua F.;Haj, Adel E.;Bristow, Emilia L.;等

发布日期:2019

发布机构:[U.S. Geological Surv...

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The U.S. Geological Survey, in cooperation with the City of Cedar Rapids, began a study in 2013 to better understand the effects of drought stress on the Cedar River alluvial aquifer. After an evaluation of the existing groundwater-flow models for the alluvial aquifer, a plan was begun to construct an updated groundwater-flow model capable of evaluating the effect of prolonged drought and increased demand. As part of the effort to update the existing groundwater-flow model, data were collected during an airborne electromagnetic (AEM) survey in May 2017. The study area for the AEM survey encompasses about 53 square kilometers of the Cedar River Basin, west of Cedar Rapids, Iowa, and includes a 19-kilometer reach of the Cedar River. The AEM survey of the Cedar River alluvial aquifer and adjacent areas was completed to characterize the subsurface geology of the area to refine a lithologic framework. The collected AEM data were postprocessed by numerical inversion using the program EM1DFM to produce subsurface apparent resistivity cross sections. Changes observed in resistivity profile values with depth were used to infer lithologic changes and delineate three of the four lithologic units designated in the lithologic framework for this area: alluvial deposits, glacial till, and bedrock; hereafter referred to as the “lithologic framework.” The fourth unit, composed of surficial eolian sediments, was not delineated in these profiles because these units are thin and discontinuous and are not reliably distinguishable from flood plain alluvial deposits. For the purposes of delineating lithologic units using the AEM data, bedrock was assumed to be the lowest unit in a profile, glacial till was deposited on a bedrock surface, and alluvium was deposited on erosional till or bedrock surfaces.

A three-dimensional fence diagram was created as part of the lithologic framework to further define the extent and thickness of the lithologic units near the Cedar River alluvial aquifer. The fence diagram shows a three-dimensional perspective of unit thickness, extent, and orientation of the delineated lithologic framework. A lithologic framework, by design, is intended to represent a simplification of a more complex natural system through data interpolation between known points, which usually are lithologic logs. The resistivity profiles produced from the AEM survey allow for continuous mapping and accurate interpolation of lithology between lithologic logs; however, the apparent resistivity value may reflect several characteristics of subsurface materials including variations in lithology, porosity, water quality, grain sorting, and degree of saturation. In this study, the only variables considered were those related to changes in the subsurface material.

作者:Schenk, Christopher J.;Brownfield, Michael E.;Mercier, Tracey J.;等

发布日期:2019

发布机构:[U.S. Geological Surv...

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Using a geology-based assessment methodology, the U.S. Geological Survey estimated undiscovered, technically recoverable mean resources of 1.3 billion barrels of oil and 63 trillion cubic feet of gas in the Reggane Basin Province of Algeria.

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发布日期:2019

发布机构:[Publications office ...

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This report details a recommendation for a much-needed Blue Economy Investment Platform (BEIP) to address major market failures to supply capital to high potential innovative young businesses. It recommends establishing an umbrella fund to channel additional funds into fund managers wholly or pa...

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发布日期:2019

发布机构:[Publications office ...

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Analysis of the local elections held in Syria on the 16th of September 2018 reveals a significant gap between the high level of regime mobilization to bring them about and the low level of civilian expectations regarding their process and results. Voter participation was low, due to a significan...

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发布日期:2019

发布机构:[Publications office ...

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Since 2012 the JRC has been working on the development of a water module in the CAPRI model to allow expanding the analysis of agricultural policy to cover water related issues. This report describes the latest improvements to the module including the change to 2012 base year, the update of the ...