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991.
Ultrathin dielectric materials that provide high capacitance values are needed for 64- and 256-Mb stacked DRAMs. It is shown that capacitance values as high as 12.3 fF/μm2 can be obtained with ultrathin nitride-based layers deposited on rugged polysilicon storage electrodes. These films present the reliability and low leakage current levels required for 3.3-V applications. The nitride thickness, however, cannot be scaled much below 6 nm to avoid the oxidation-punchthrough mechanisms that appear when too-thin films are unable to withstand the reoxidation step  相似文献   
992.
In order to produce mAbs directed specifically against HLA-DR10 molecule, transfected mouse L cells, expressing the DRB1*1001 allele, were used to immunize C3H mice over a period of 4 weeks. Two mAbs, 2C12 and 4B6, derived from this fusion were found to recognize, with different affinity, polymorphic epitopes of DR10 that are shared with DR1, 3, 7, and 9. These mAbs were screened on a large panel of homozygous B lymphoblastoid cell lines using microlymphocytotoxicity and the results were confirmed by flow cytometry. The reactive pattern of 2C12 and 4B6 was compared to that of MP10 human mAb also recognizing the DR10 specificity in addition to DR1, 2 and 9. Based on serologic specificity and cellular absorption experiments, we conclude that the epitopes the murine and human mAbs respectively recognize on the DR10 molecule, are probably different.  相似文献   
993.
994.
The uniaxial bianisotropic medium is a generalisation of the bi-isotropic and chiral media which recently have been subject to intensive research. Such a medium results, for example, when microscopic helices with parallel axes are positioned in a host dielectric in random locations. Plane wave propagation in such a medium is studied and a simple solution for the dispersion equation is found. Numerical examples for the wave number surfaces of the medium are given.<>  相似文献   
995.
996.
997.
The results are presented of experimental examination of the effect of the grain size on the spoliation of copper. Levels of the loading pressure, corresponding to various stages of spollation, were determined for two initial states characterized by a mean grain size of 0.29 and 1.62 mm. The results show that for the material with the smaller grain these levels are approximately 0.2 GPa higher than for the material with the larger grain size.Translated from Problemy Prochnosti, No. 2, pp. 73–75, February, 1996.  相似文献   
998.
A statistically admissible solution has been constructed for a pipe with an axial through crack. The boundaries of the limit region have been obtained and the strength conditions on its boundary have been formulated. The extension of the distribution of forces and moments beyond the limit region boundary has been substantiated. The results obtained for a pipe with closed ends are in fair agreement with the experimental data. The influence of the axial force and the property anisotropy upon the fracture stress has been studied. The possibility of considering several cracks is analysed.  相似文献   
999.
A method of calculating the response of sensitive elements based on wave delay devices is described using as an example a gauge for measuring the diameter of holes in metal objects. The efficiency of a sensitive element consisting a cylindrical helix with a longitudinally conducting shield is demonstrated. Translated from Izmeritel'naya Tekhnika, No. 9, pp. 46–50, September, 1996.  相似文献   
1000.
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