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991.
Changes in the phase compositions and microstructures of magnesia-partially-stabilized zirconia (Mg-PSZ) were studied in water at 80–300 °C, 1 m HCl solutions at 80–140 °C and 1 m CH3COOH-CH3COONa buffer solutions at pH 3 and 80–140 °C for 10–40 days. The tetragonal to monoclinic phase transformation and the degradation of the fracture strength occurred in water above 200 °C. On the other hand, although no noticeable tetragonal to monoclinic phase transformation proceeded in 1 m HCl solutions and 1 m CH3COOH-CH3-COONa buffer solutions at pH 3 below 140 °C, the fracture strength of Mg-PSZ greatly degraded. The dissolution of Mg2+ ion was observed in water above 200 °C and in 1 m HCl solutions above 80 °C. 相似文献
992.
993.
N. V. Vostokov Yu. N. Drozdov Z. F. Krasil’nik O. A. Kuznetsov A. V. Novikov V. A. Perevoshchikov M. V. Shaleev 《Russian Microelectronics》2005,34(4):203-209
The results are presented of the fabrication of strain-relaxed graded Si1 − x
Gex/Si(001) buffer layers with a maximum Ge fraction of about 0.25 that have a low density of threading dislocations (<106 cm−2) and low surface roughness. The buffer layers are grown by atmospheric-pressure hydride CVD. It is found that chemical mechanical polishing can reduce their surface roughness to a level comparable with that of the original Si(001) substrates. It is shown that the polished buffer layers can serve as substrates for MBE-grown SiGe/Si heterostructures.__________Translated from Mikroelektronika, Vol. 34, No. 4, 2005, pp. 243–250.Original Russian Text Copyright © 2005 by Vostokov, Drozdov, Krasil’nik, Kuznetsov, Novikov, Perevoshchikov, Shaleev. 相似文献
994.
Autoscan: a scan design without external scan inputs or outputs 总被引:1,自引:0,他引:1
Pomeranz I. Reddy S.M. 《Very Large Scale Integration (VLSI) Systems, IEEE Transactions on》2005,13(9):1087-1095
We propose a design-for-testability technique for synchronous sequential circuits called autoscan. Autoscan uses scan chains similar to conventional scan. However, it gives up the external scan inputs and outputs in order to eliminate the test data volume associated with them. Scan operations under autoscan improve the circuit testability by allowing the circuit state to be modified through shifting. Due to the removal of the scan inputs and outputs, synthesis of scan chains under autoscan does not have to satisfy all the constraints imposed on conventional scan chains. We describe a synthesis procedure for autoscan chains, and demonstrate that autoscan allows us to detect almost all the faults that are detectable using conventional scan. We use random sequences in order to show that sequential test generation is not necessary under autoscan. We also describe a test generation procedure, and discuss the effect of autoscan on fault diagnosis. 相似文献
995.
M. M. Stadnyk 《Materials Science》2007,43(6):764-768
We deduce the theoretical formula taking into account the influence of biaxial loading of a plate weakened by a crack on the
stress intensity factor K
I. This enables us to compute the characteristic of crack resistance K
c according to the known boundary forces.
__________
Translated from Fizyko-Khimichna Mekhanika Materialiv, Vol. 43, No. 6, pp. 14–16, November–December, 2007. 相似文献
996.
The paper describes an experimental investigation of the diamond-like carbon deposition process from methane precursor with an innovative high-density inductively coupled plasma source. It appears that a high plasma density allows a fast growth of diamond-like carbon coatings exhibiting a high hardness. In contrast to what is usually found in the literature, it seems that the ion species participate significantly to the growth of the carbon film when exposed to a high ion flux. 相似文献
997.
Ya. O. Shablovskii 《Inorganic Materials》2007,43(12):1345-1349
The pyroelectric properties of lithium sulfate have been studied theoretically on the hypothesis of a pseudosymmetry of the structure of its polar phase. Analytical expressions are proposed for the temperature dependences of its pyroelectric polarization and pyroelectric coefficient at low temperatures and near the polymorphic transformation. The pyroelectric and piezoelectric coefficients of a polar crystal are shown to be in direct proportion. 相似文献
998.
M. V. Zagidullin V. D. Nikolaev M. I. Svistun N. A. Khvatov 《Journal of Engineering Physics and Thermophysics》2007,80(3):555-562
The results of parametric tests of a centrifugal bubble singlet-oxygen generator based on the reaction of chlorine with an
alkaline hydrogen peroxide solution have been given. The utilization of chlorine grows with bubble-layer height, whereas the
relative content of O2(1Δ) remains constant. Growth in centrifugal acceleration leads to a more efficient utilization of chlorine. A specific oxygen
output of more than 1 mmole·cm−2·sec−1 from the bubble layer for a degree of chlorine utilization of ∼95% and a singlet-oxygen yield of more than 50% has been attained.
It has been shown that a centrifugal bubble singlet-oxygen generator is an efficient energy source for an oxygen-iodine laser.
__________
Translated from Inzhenerno-Fizicheskii Zhurnal, Vol. 80, No. 3, pp. 121–128, May–June, 2007. 相似文献
999.
Split ring-rod combination metamaterial is used as a substrate material in a microstrip guided wave structure to determine what the effect is of a material with potentially excessive dispersion or loss or both. A Green's function method readily incorporates the metamaterial permittivity and permeability tensor characteristics. Ab initio calculations are performed to obtain the dispersion diagrams of several complex propagation constant modes of the structure. Analytical analysis is done for the design and interpretation of the results, which demonstrate remarkable potential for realistic use in high frequency electronics, while showing modes with extremely low loss bands. 相似文献
1000.
Holly Rushmeier Jason Dykes John Dill Peter Yoon 《Computer Graphics and Applications, IEEE》2007,27(6):12-16
Defining visualization education is still a work in progress. Visualization education is not just a subject within computer science. Computer scientists are not always the appropriate choice to teach visualization courses on their own. Visualization is not just mastering a set of concepts but acquiring skills. Student should learn by doing, either using one tool or a variety of tools, depending on the course's focus. 相似文献