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51.
The Nuclear Waste Management Organization is evaluating the safety and feasibility of the permanent disposal of used nuclear fuel in a deep geological repository. Their current design concept utilises copper-coated steel used fuel containers to isolate the waste from the environment. Immediately following repository closure, a finite quantity of O2 will be trapped inside the repository and could cause some amount of oxic corrosion to the outer copper layer of the containers. On a per container basis, 13?mol of O2 will be trapped in the repository rooms at the time of closure, based on reference design dimensions. This corresponds to a maximum depth of copper corrosion of 81?μm, assuming a uniform distribution. This work also considers the sensitivity of this oxic corrosion allowance to various hypothetical design changes to the repository that may occur before or during construction. 相似文献
52.
A study was conducted to identity factors contributing to the difficult removal of used motor oil from textile materials by
detergency. Infrared spectroscopy and gel permeation chromatography of used motor oil showed that the oil was a saturated
aliphatic hydrocarbon with molecular weight around 950. X-ray analysis revealed that particulates present in the used motor
oil contained S, Mg, Al, Si, K, Ca, Fe, Ni, Cu, and Zn. Used motor oil was distributed throughout the cotton fibers with similar
concentration of oil in the lumen, secondary wall, and surface crenulation. Higher relative concentrations of used motor oil
were observed in the secondary wall of the fiber than has been reported for human sebum. No oil was found in the interior
of polyester fibers although high concentrations of oil were detected in the interfiber spaces and on the fiber surfaces of
polyester fibers. Dispersant additives of motor oil are though to enhance penetration into the cotton structure and wicking
over the polyester fibers, making the nonpolar used motor oil very difficult to remove by detergency. 相似文献
53.
54.
In the paper the main goals and progress of the surveillance specimen programme for the RPVs WWER-440/213 in Jaslovské Bohunice V-2 and Mochovce NPPs are presented. At Jaslovské Bohunice V-2, the standard surveillance specimen programme (SSSP) was finished and so-called ‘Extended Surveillance Specimen Programme’ (ESSP) was prepared on the base of its critical analysis. For first two units of the Mochovce NPP completely new programmes of irradiation embrittlement monitoring called ‘Modern Surveillance Specimen Programme’ is prepared. It is based on the experience with SSSP and ESSP as well as the recommendations of IAEA experts. This programme will serve for Mochovce NPP during all planned service life. The experience of ESSP application on the 3rd and 4th units in Jaslovské Bohunice V-2 NPP are presented in the paper too. 相似文献
55.
酯硬化水玻璃砂工艺及其旧砂再生 总被引:1,自引:0,他引:1
介绍了酯硬化水玻璃砂工艺及其旧砂的特点,对影响酯硬化水玻璃砂工艺推广应用的旧砂再生问题作了较详细的论述. 相似文献
56.
作者在掌握了大量现场资料和文献资料的基础上,全面系统地论述了国内外汽车工业用铝材的发展现状与趋势,汽车用铝合金及主要零部件的铝化程度、汽车用铝合金的新开发,我国汽车用铝材的研发与应用状况等问题。指出汽车材料铝化是现代汽车轻量化的主要途径。对加速我国汽车工业用材的国产化和铝化提出了建议。 相似文献
57.
Analysis of time-series MODIS 250 m vegetation index data for crop classification in the U.S. Central Great Plains 总被引:11,自引:0,他引:11
Brian D. Wardlow Stephen L. Egbert Jude H. Kastens 《Remote sensing of environment》2007,108(3):290-310
The global environmental change research community requires improved and up-to-date land use/land cover (LULC) datasets at regional to global scales to support a variety of science and policy applications. Considerable strides have been made to improve large-area LULC datasets, but little emphasis has been placed on thematically detailed crop mapping, despite the considerable influence of management activities in the cropland sector on various environmental processes and the economy. Time-series MODIS 250 m Vegetation Index (VI) datasets hold considerable promise for large-area crop mapping in an agriculturally intensive region such as the U.S. Central Great Plains, given their global coverage, intermediate spatial resolution, high temporal resolution (16-day composite period), and cost-free status. However, the specific spectral-temporal information contained in these data has yet to be thoroughly explored and their applicability for large-area crop-related LULC classification is relatively unknown. The objective of this research was to investigate the general applicability of the time-series MODIS 250 m Enhanced Vegetation Index (EVI) and Normalized Difference Vegetation Index (NDVI) datasets for crop-related LULC classification in this region. A combination of graphical and statistical analyses were performed on a 12-month time-series of MODIS EVI and NDVI data from more than 2000 cropped field sites across the U.S. state of Kansas. Both MODIS VI datasets were found to have sufficient spatial, spectral, and temporal resolutions to detect unique multi-temporal signatures for each of the region's major crop types (alfalfa, corn, sorghum, soybeans, and winter wheat) and management practices (double crop, fallow, and irrigation). Each crop's multi-temporal VI signature was consistent with its general phenological characteristics and most crop classes were spectrally separable at some point during the growing season. Regional intra-class VI signature variations were found for some crops across Kansas that reflected the state's climate and planting time differences. The multi-temporal EVI and NDVI data tracked similar seasonal responses for all crops and were highly correlated across the growing season. However, differences between EVI and NDVI responses were most pronounced during the senescence phase of the growing season. 相似文献
58.
A kinetic model of the rigid and flexible coupling system for terminally sensitive submunition is set up with Kane's method. The parachute is considered as a flexible body, the flexible displacement is expressed with modal spread method, the position of the parachute is expressed with a hybrid coordinate method, and the kinematics of the terminally sensitive submunition is analyzed. Ten generalized coordinates relative to the attitude of the terminally sensitive submunition are chosen, and the correlative generalized active forces, the generalized inertial forces, the generalized internal forces are calculated in turn. On the base of the Kane's method, the ten degrees of freedom dynamic equations for the coupled terminally sensitive submunition are finally set up. This model can be used to expediently simulate and analyze accurately the exterior ballistic trajectory of terminally sensitive submunition, and provide the overall design of the terminally sensitive submunition with some helpful references. 相似文献
59.
介绍了一种新型双线制医用呼叫系统的实现原理。该系统采用电源载波技术,利用系统的两芯电源线,实现语音信息和呼叫信息的交换。系统主机由MCS51系列单片机实现,呼叫分机由PIC单片机实现。系统具有可靠性高、成本低、功能强大、安装方便等优点,具有较强的实用价值。 相似文献
60.