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101.
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Charles Fairhurst Ferruccio Gera Paul Gnirk Malcolm Gray Bengt Stillborg 《Tunnelling and Underground Space Technology incorporating Trenchless Technology Research》1993,8(3)
The International Stripa Project was a cooperative research and development project among several member countries of the Nuclear Energy Agency of the Organization for Economic Cooperation and Development. The scientific and technical objectives of the project were to investigate several aspects of technology concerned with the feasibility and safety of disposal of long-lived, heat-generating radioactive waste at depth in granitic rocks. In particular, the Stripa Project addressed: 1) the development of instruments and procedures to characterize candidate repository sites; 2) the understanding and modelling of groundwater flow and solute transport in fractured crystalline rock; and 3) the design of engineered barriers capable of contributing to waste isolation by restricting groundwater flow in proximity to the waste containers and in the surrounding host rock. This overview summarizes the work focussed on natural barriers and engineered barriers. 相似文献
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A theoretical-experimental study of tandem-junction, front-surface-field, and interdigitated-back-contact solar cells is presented. The approach taken in the theoretical analysis emphasizes detailed qualitative physical reasoning which leads to quantitative results. This approach enables the three-dimensional boundary-value problems describing these solar cells to be made tractable. A major result is a unifying view of the physics underlying the performance of these cells. The important physical mechanisms are identified and described, and cell design considerations and trade-offs are discussed. 相似文献
106.
B?ckman Lars; Hill Robert D.; Herlitz Agneta; Fratiglioni Laura; Winblad Bengt 《Canadian Metallurgical Quarterly》1994,9(4):520
Whether individual differences in demographic, psychometric, and biological domains can predict episodic memory in dementia was investigated. Mildly to moderately demented very old persons performed episodic memory tasks (free recall and recognition of slowly and rapidly presented random words, free and cued recall of organizable words, and recognition of dated and contemporary famous faces). A factor analysis of the memory measures yielded 2 factors, 1 indexing recall and 1 recognition. Controlling for severity of dementia, only 2 predictors contributed to performance: (a) Block Design (a marker of fluid intelligence) was positively related to recall, and (b) age was negatively related to recognition. Although these results are similar to data reported on predictors of episodic memory in normal aging, (a) the number of predictive variables appears to be reduced in dementia, and (b) age seems to affect recall and recognition differentially in normal aging and dementia. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
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The Fourier transforms of the three field components of a finite width reproducing head are derived and given in analytic forms. These formulas represent three-dimensional analogs of the familiar two-dimensional exponential spacing loss factor. The on- and off-track head response to a longitudinally magnetized track is computed from these results and compared with experimental measurements on registration loss and read crosstalk. As long as the head-to-medium separation and medium thickness are small compared to the head width, the results are in relatively simple analytic forms. 相似文献
109.
A highly sensitive and accurate reference method for determination of docosenoic acid (mainly erucic acid, 22∶1n−9) in different
rapeseed oils is described. A fixed amount of [1-14C]erucic acid methyl ester (about 1 μg) is added to a fixed amount of oil. After treatment with sodium methoxide/methanol
reagent and extraction with hexane, the amount of unlabeled erucic acid is determined from the ratio between the recordings
at m/e 320 and m/e 322 obtained after analysis with a combined gas chromatograph-mass spectrometer equipped with an MID (multiple
ion detector). The two ions used correspond to the M-32 peak in the mass spectrum of unlabeled and [1-14C]labeled erucic acid methyl ester. The relative standard deviation of the method is about 1.8%. The method was compared with
a gas chromatographic method for determination of erucic acid. 相似文献
110.
Review of translocations detected by FISH for retrospective biological dosimetry applications 总被引:2,自引:0,他引:2
Edwards AA Lindholm C Darroudi F Stephan G Romm H Barquinero J Barrios L Caballin MR Roy L Whitehouse CA Tawn EJ Moquet J Lloyd DC Voisin P 《Radiation protection dosimetry》2005,113(4):396-402
Several European laboratories have combined their research efforts to arrive at a consensus view on using fluorescence in situ hybridisation (FISH) for retrospective dosimetry. The aim of this review is to report these views and to highlight some areas where further work is needed. Translocations in the stable cells should be measured only in the cells that contain the full complement of the painted material. Two-way and one-way translocations should be combined with equal weight. The control level of translocations has a strong dependence on age, which has now been measured and the system has been calibrated. In conclusion, the technique works and a lifetime dose to the bone marrow from low-linear energy transfer radiation of 0.5 Gy above normal background levels can be measured for any individual. The main application is considered to provide an independent verification of lifetime doses to individuals who might form a part of an epidemiological study. 相似文献