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91.
The Grimsel Test Site (Felslabor Grimsel — FLG) is situated at a depth of 450 m in the Juchlistock massif of the Bernese Oberland. It is managed by the National Cooperative for the Storage of Radioactive Waste (NAGRA-Switzerland).By means of a heater test, the power output of canisters filled with high-level waste is simulated. This heater test is performed by the German Gesellschaft für Strahlen- und Umweltforschung — GSF. Two electrical heaters, with a heatable length of 6 m, a diameter of 0.3 m and an available power of 4 kW/m, are installed in two vertical boreholes. One of them is located in the granite adjacent to a strongly fractured lamprophyre vein, the other one directly within this disturbed zone. They are operating since August 1986.The thermo-mechanical reaction of the rock mass is registered by a large number of measurement devices which are installed in an array of instrument boreholes around the heaters. They record the deformation and the alteration of rock stresses, the pore water pressure and the water conductivity caused by heating. 相似文献
92.
R. Bunk U. Leske R. Krompass Z. Pretch K. Rudolf R. Herbig K. Pitch V. A. Tsykanov O. V. Skiba V. A. Makarov L. P. Bol'shakov P. T. Porodnov A. A. Maershin S. S. Keruchen'ko 《Atomic Energy》1989,67(5):802-806
Translated from Atomnaya Énergiya, Vol. 67, No. 5, pp. 320–323, November, 1989. 相似文献
93.
U. Jakubowski 《Ultramicroscopy》1985,17(4):379-382
Drift and vibration are the main factors limiting the resolution that can be attained with liquid-nitrogen (LN2)-cooled cryoholders. Tests with a Gatan holder show that resolution is usually anisotropic. We propose that the metallic heat-conducting element could be replaced by a heat pipe, because such a device can, in principle, minimize drift. The vibration problem could be combatted by using supercooled cryogens. 相似文献
94.
Herzog H.-J. Hackbarth T. Seiler U. Konig U. Luysberg M. Hollander B. Mantl S. 《Electron Device Letters, IEEE》2002,23(8):485-487
Si/SiGe n-type modulation-doped field-effect transistors grown on a very thin strain-relieved Si/sub 0.69/Ge/sub 0.31/ buffer on top of a Si(100) substrate were fabricated and characterized. This novel type of virtual substrate has been created by means of a high dose He ion implantation localized beneath a 95-nm-thick pseudomorphic SiGe layer on Si followed by a strain relaxing annealing step at 850/spl deg/C. The layers were grown by molecular beam epitaxy. Electron mobilities of 1415 cm/sup 2//Vs and 5270 cm/sup 2//Vs were measured at room temperature and 77 K, respectively, at a sheet carrier density of about 3/spl times/10/sup 12//cm/sup 2/. The fabricated transistors with Pt-Schottky gates showed good dc characteristics with a drain current of 330 mA/mm and a transconductance of 200 mS/mm. Cutoff frequencies of f/sub t/=49 GHz and f/sub max/=95 GHz at 100 nm gate length were obtained which are quite close to the figures of merit of a control sample grown on a conventional, thick Si/sub 0.7/Ge/sub 0.3/ buffer. 相似文献
95.
B Decchi A Zalaffi R Spidalieri U Arrigucci AM Di Troia A Rossi 《Canadian Metallurgical Quarterly》1997,105(6):484-489
We describe here the results of a screening program conducted to discover inhibitors of the type-I interleukin-1 receptor (IL-1RI) from samples of microbial origin. An innovative approach, based on automated, nonradioactive receptor binding assays has been employed. Specially prepared cell-free systems have allowed the use of high concentrations of microbial metabolites in the reaction mixtures with a low percentage of false positives. More than 30,000 microbial samples from different species of soil isolates have been tested and two interesting activities have been purified and characterized. One of these, isolated from Streptomyces sp. GE48009, was identified as niphimycin, an antifungal agent also known as scopafungin. Preliminary evidence suggests that this molecule and azalomycin F, a structural analogue, inhibit IL-IRI by virtue of their long-chain guanidinium moiety. The other activity, isolated from Aspergillus sp. GE49752, was identified as flavipin, a substituted o-phthalaldehyde. 相似文献
96.
97.
The aim of the present study was to assess the prognostic relevance of relatives' interactive behaviour towards the patient, as covered by the Münster Family Interview (MFI), to the further course of the schizophrenic illness. The MFI is a family interview (of the whole family, including the patient) designed to record the emotional family atmosphere based on the concept of expressed emotion (EE). The ratings take place directly after the interview on five scales (criticism, hostility, overinvolvement, resignation and warmth), the resignation scale being added to the 'classic' EE scales. Ninety-nine families of outpatients diagnosed with schizophrenia according to the DSM-III were examined with the MFI during a home visit. The patients were seen 1 and 2 years after the first examination. The target criteria selected for the prognostic significance of the interaction measurements were: rehospitalisation within 2 years; extent of symptoms after 1 year, and psychosocial skills after 1 year. The significance of the interaction dimensions was verified in regression models. The control variable used in the regression models was the Strauss-Carpenter scale. Regression models were produced for the total group and for a subgroup of moderately ill patients. All target criteria yielded serviceable prediction models. The most important variable for prediction was the control variable, the Strauss-Carpenter scale. However the interaction variables made additional contributions to the prognosis, especially in the subgroup of moderately ill patients. The best MFI scale for all the outcome criteria was resignation; criticism predicted only the symptomatology, and emotional overinvolvement the level of social functioning after 1 year. In conclusion, practical work with families of schizophrenic patients should emphasise the protective function of relatives towards patients more strongly. 相似文献
98.
99.
HG Brochhagen G Benz-Bohm U Mennicken S Schickendantz A Borowski KJ Lackner 《Canadian Metallurgical Quarterly》1997,27(2):181-183
Annuloaortic ectasia due to Shprintzen-Goldberg syndrome (SGS) is reported. A 10-year-old boy was admitted to our hospital for evaluation of chest pain. On admission, he was diagnosed as SGS on the basis of his various anomalies. Two-dimensional echocardiography showed a bicuspid aortic valve and marked annular dilatation, Doppler flow studies revealed severe aortic regurgitation, and retrograde aortography showed severe aortic regurgitation with annular dilatation. Successful aortic root replacement was performed; subsequent histologic examination of the ascending aorta demonstrated cystic medial necrosis. In conclusion, SGS is a generalized connective tissue dysplasia, with clinical manifestations of cardiovascular lesions similar to those in Marfan syndrome. Aortic root replacement was successfully performed; however, recurrence of aortic aneurysms outside of the ascending aorta should be carefully observed. Surgical treatment for cardiovascular disorders may be necessary to save the life of patients with SGS. 相似文献
100.
T. MATTILA-SANDHOLM T. ALI-VEHMAS G. WIRTANEN U. RÖNNER M. SANDHOLM 《International Journal of Food Science & Technology》1991,26(3):325-336
Automated monitoring of the microbiological quality of heat-processed foods by the resazurin reduction test was applied to microtitration plate incubator-fluorimeter technology. The appearance and disappearance of the fluorescing peak of resorufin was monitored on microtitration trays. Pasteurized or ultra-high temperature-treated starch-based soup was used as the model food system. Bacillus subtilis spores (ultra-high temperature treatment) and vegetative cells of Enterococcus faecalis (pasteurization) were inoculated into the soup before the heat treatment at levels which resulted in some survival. The timing of appearance of maximum fluorescence correlated with the number of bacteria in pre-incubated samples. Automated resazurin-reduction fluorimetry was compared with conventional plating, turbidometry and microcolony count by the direct epifluorescent filter technique. The results of the resazurin test correlated well with those of all the other methods tested. Fluorimetry had the advantage that the results could be read within 1–5h and the reproducibility was superior to the other methods. 相似文献