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991.
The behavior of hydrogen in solids under the action of intense ionizing radiation is of importance in solving numerous problems of materials science for the nuclear and thermonuclear power industry, spacecraft engineering, hydrogen energetics, and microelectronics. Experimental results are presented that provide evidence of the radiation-induced yield of hydrogen from single crystal silicon bombarded with 710-MeV bismuth ions. 相似文献
992.
The methods of X-ray photoelectron spectroscopy and Auger spectroscopy are used to study surface films formed on zinc and zinc-plated steel in the process of holding in aqueous extracts of mixtures of phosphate and calcium-containing pigments. It is shown that protective films formed mainly of zinc and calcium phosphates of different chemical structure are deposited in inhibited solutions on specimens of pure zinc and zinc-plated steel. The protective properties of these films are much better than the protective properties of the surface layers formed on the metal in the extracts of a single phosphate (or calcium-containing) pigment. The mixture of these pigments may serve as a promising substitution of chromate inhibitors in anticorrosive organic coatings. 相似文献
993.
994.
A second-order cross-coupled combline filter which has three finite transmission zeros is presented. The problem of the frequency-invariant coupling in a real circuit is introduced. To make extra transmission zeros, a top metalized dielectric block is used. 相似文献
995.
Sokolovsky V. Meerovich V. Vajda I. Beilin V. 《Applied Superconductivity, IEEE Transactions on》2004,14(3):1990-2000
Design, parameters, and application areas of a superconducting fault current limiter (FCL) are analyzed on the basis of the requirements of power systems. The comparison of resistive and inductive designs is carried out. An example of the effective application of FCLs in distribution substations is considered and the gain from the FCL installation is discussed. It is shown that an FCL not only limits a fault current but also increases the dynamic stability of the synchronous operation of electric machines. The calculation procedure of the parameters of an inductive FCL for a specific application case is described. 相似文献
996.
The sequence of reactions in the reduction of manganese metaniobate with Nb, NbO, and Ta is studied. The reduction of MnNb2O6 by Nb or NbO differs in some respects from that by Ta. No Mn(Nb2 – x
Ta
x
)O4.33 or Mn(Nb2 – x
Ta
x
)O3.67 solid solutions were detected in the reduction products. Tantalum converts directly into manganese metatantalate, without oxidation according to the scheme Ta–TaO–TaO2–Ta2O5. A reaction scheme is suggested for the reduction of MnNb2O6 by niobium and tantalum. The unit-cell parameters of the orthorhombic phase MnNb2O4.33 resulting from the reduction of MnNb2O6 with Nb or Ta are determined. 相似文献
997.
A weighting algorithm to determine the coordinates of the center of a Gaussian laser beam projected onto a matrix photodetector is considered. The influence of the internal noise of the photodetector, the maximum brightness of the signal at the beam maximum, and the beam radius on the precision of the algorithm is investigated. Recommendations on image processing are presented. 相似文献
998.
The interaction of NbVNi with hydrogen is studied over wide pressure and temperature ranges. Hydrogen absorption–desorption isotherms are measured, and the compositions of the resulting hydride phases are determined. X-ray diffraction analysis demonstrates that the incorporation of hydrogen into NbVNi leads to an isotropic expansion of its crystal lattice. 相似文献
999.
Syed M. Alam Donald E. Troxel Carl V. Thompson 《Analog Integrated Circuits and Signal Processing》2003,35(2-3):199-206
In this paper, we describe a comprehensive layout methodology for bonded three-dimensional integrated circuits (3D ICs). In bonded 3D integration technology, parts of a circuit are fabricated on different wafers, and then, the wafers are bonded with a glue layer of Cu or polymer based adhesive. Using our layout methodology, designers can layout such 3D circuits with necessary information on inter-wafer via/contact and orientation of each wafer embedded in the layout. We have implemented the layout methodology in 3DMagic. Availability of 3DMagic has led to interesting research with a wide range of layout-specific circuit evaluation, from performance comparison of 2D and 3D circuits to layout-specific reliability analyses in 3D circuits. Using 3DMagic, researchers have designed and simulated an 8-bit encryption processor mapped into 2D and 3D FPGA layouts. Moreover, the layout methodology is an essential element of our ongoing research for the framework of a novel Reliability Computer Aided Design tool, ERNI-3D. 相似文献
1000.
Lomakin V. Nan-Wei Chen Shuqing Li Michielssen E. 《Microwave and Wireless Components Letters, IEEE》2004,14(7):355-357
A two-period array of subwavelength holes in a perfect electrically conducting plate permits enhanced transmission of incident plane waves with wavenumbers near those of leaky waves supported by the array. A simple periodic impedance sheet model explains this phenomenon and provides an approximate expression for the transmission peak location. Transmission through thin perforated plates is studied using a full-wave solver to verify model-theoretic observations. Transmission coefficient peak splitting and narrowing phenomena, associated with thick perforated plates, are explored. 相似文献