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991.
P. Kurpas A. Oster M. Weyers A. Rumberg K. Knorr W. Richter 《Journal of Electronic Materials》1997,26(10):1159-1163
Reflectance anisotropy spectroscopy (RAS) has been used to study As-by-P exchange during metalorganic vapor phase epitaxy.
The study focuses on the processes occurring during switching from GaAs to GaInP, especially the effect of purging PH3 over a GaAs surface. GaAsP/GaAs superlattices of different periodicity were grown and the P-content was determined by high-resolution
x-ray diffraction and correlated to the RAS spectra. From the temperature dependence of the P-content, an activation energy
of 0.56 eV was estimated for the incorporation mechanism. In addition to the insights into the processes at mixed group-V
heterointerfaces, our study demonstrates the reproducibility of RAS transients that thus can be used for process monitoring. 相似文献
992.
A simple model based on the Orowan equation and the dynamic evolution of the dislocation structure by generation and merging
of slipped areas is used to see which experimental results on creep of pure and solute-hardened crystalline materials can
or cannot be explained with regard to creep with refinement or coarsening of the dislocation structure and steady-state creep.
Quantitative deficiencies of the model for pure materials are discussed; most of them are related to neglection of subgrain
formation.
This article is based on a presentation made in the workshop entitled “Mechanisms of Elevated Temperature Plasticity and Fracture,”
which was held June 27–29, 2001, in San Diego, CA, concurrent with the 2001 Joint Applied Mechanics and Materials Summer Conference.
The workshop was sponsored by Basic Energy Sciences of the United States Department of Energy. 相似文献
993.
994.
The simultaneous grinding/agglormeration process has been used to beneficiate Minto coal. Experiments with the Szego Mill, a planetary ring-roller mill with grooved rollers, have given good results. Different roller ridge/groove sizes have been tested and favourable oil-coal-water ratios established. Ash removal is closely related to grinding performance. Very short mill residence times, of the order of 10 seconds, are sufficient for microagglomerate formation. Considerable equipment and operating cost savings are possible with the modified process. 相似文献
995.
Xiaoling He Hodgson J.W. 《Intelligent Transportation Systems, IEEE Transactions on》2002,3(4):244-251
For pt.I see ibid., vol.3, no.4, p.235-43 (2002). Hybrid electric vehicle (HEV) simulation is conducted based on the model developed for a parallel HEV built in the University of Tennessee, Knoxville (UT-HEV). The HEV simulation is a parametric analysis of the power control schemes and vehicle performance. Major parameters are evaluated for the vehicle driven under the standard urban and highway driving schedules. The results indicate that current configuration of the UT-HEV NEON has superb capability for battery state of charge (SOC) recovery while meeting the velocity request of the given driving schedules. Recommendations are given from the simulation for optimal performance in light of the HEV power control, capability for SOC recovery through regeneration and regenerative braking, as well as velocity, acceleration and range performance. 相似文献
996.
A method of determination for solasodine glycosides by using thin-layer chromatography (TLC) immunostaining was investigated. Solasodine glycosides separated by silica gel TLC were transferred to a polyvinylidene difluoride membrane. The membrane was treated with sodium periodate solution followed by bovine serum albumin (BSA), resulting in a solasodine glycoside-BSA conjugate. Conjugation was confirmed by matrix-assisted laser desorption/ionization mass spectrometry. Individual spots were stained by monoclonal antibody against solamargine. Immunostaining of solasodine glycosides was more sensitive compared to other stainings. The newly established immunostaining method can be extended to analysis of the distribution of solasodine glycoside in the plant body. 相似文献
997.
Park Y.C. Lee K.Y. Youn D.H. Kim N.H. Kim W.K. Park S.H. 《IEEE transactions on bio-medical engineering》1992,39(8):868-871
An efficient algorithm detecting the presence of a fetal QRS complex is presented. The proposed fetal QRS detection method computes the averaged magnitude of the difference between the fetal ECG signal and the reference signal to detect the fetal QRS event. The detected fetal QRS complexes are exponentially averaged to generate the template signal which can track the slowly varying shape of the fetal ECG signal. As an effort to obtain improved detection performances, two approaches of normalizing the fetal ECG signal and the template are considered. 相似文献
998.
The authors demonstrate the application of a commercially available SiGe heterojunction bipolar transistor monolithic microwave integrated circuit technology to active mixers in future communication systems at 5.7 GHz and above. This technology can be used to realise circuits with less than 50 mW power consumption, conversion gains above 15 dB and small double sideband noise figures of 3.6 and 9.4 dB for 5.7 and 11.2 GHz Gilbert cell mixer circuits, respectively 相似文献
999.
Modeling of stress and electromigration at the microscopic level, in confined interconnect metallic lines with tungsten studs, can very well account for the resistance behaviour in time. The resistance change at saturation for a metallic line with blocking boundaries at both ends can be related, according to the model, to threshold product (jL)c found by Blech [1]. 相似文献
1000.