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151.
152.
N Ferrara G Longobardi N Guerra A Nicolino D Acanfora G Furgi L Odierna R Rosiello F Rengo 《Canadian Metallurgical Quarterly》1996,34(1-2):37-41
We prospectively studied 10 patients with stable exertional ischaemia, selected from a larger group of patients referred for suspected coronary artery disease or to detect residual ischaemia after myocardial infarction, to evaluate pharmacokinetic changes during chronic treatment with gallopamil and its correlation with clinical efficacy in patients with coronary artery disease. Our study consisted of a 1-week run-in single-blind placebo treatment and a 4-week single-blind gallopamil treatment. At the end of the run-in period patients underwent two different exercise tests, the first 2 hours and the second 7 hours after placebo administration. During active treatment all patients underwent two different exercise tests, the first 2 hours and the second 7 hours after gallopamil (50 mg) administration on the 1st and 28th days of gallopamil therapy. On the same days in eight of the patients we evaluated gallopamil pharmacokinetic changes. Our data revealed a rapid increase of unchanged gallopamil and its metabolite (norgallopamil) in the plasma, and a peak concentration of these substances about 2 hour after oral administration on both the 1st and 28th day of observation. Moreover, our results demonstrated an increase between the first and 28th day of treatment in peak concentration of unchanged gallopamil in the plasma, and of AUC 0-infinity and AUC o-c values during chronic treatment with gallopamil. Our clinical data showed an improvement in exercise results during gallopamil therapy related to increased concentration of the drug. 相似文献
153.
154.
155.
Silicon forms the backbone of the microelectronics industry, and possibly, of the optoelectronics industry, hitherto dominated by III/V materials. One of the remaining goals is to build an optical source in silicon. Erbium exhibits luminescent 1.54 μm intra-4f transitions in both silicon and porous silicon. This paper reviews the work which has been carried out in this field and discusses some possible additional applications of erbium-doped silicon in optoelectronics, such as a novel on-chip temperature sensor. 相似文献
156.
Vernotte F. Zalamansky G. McHugh M. Lantz E. 《IEEE transactions on ultrasonics, ferroelectrics, and frequency control》1996,43(3):403-409
The concept of structure functions, which is an extension of the variance approach, is useful to determine the variance (the structure function) which is optimized for a type of noise and for an order of drift. The multivariance method was developed to use different variances over the same signal. It is then possible to select a set of variances in which each variance is optimized to the determination of one parameter (of one noise level, drift, or cutoff frequency). Recently, we adapted this method to irregularly spaced timing data. In this connection, we replaced the structure functions by another method of spectral density estimation: the lowest-mode estimator, introduced by J.E. Deeter and P.E. Boynton (1982, 1984) for the analysis of pulsar timing data. Different lowest-mode estimators can be constructed according to two priorities: the order of drifts that must be removed and the type of noise for which the sensitivity must be maximum. Thus, a multivariance system is developed using a set of different estimators. The details of this method are described, and the results for different signals are discussed in this paper 相似文献
157.
NIKIÉT. Translated from Atomnaya Énergiya, Vol. 75, No. 4, pp. 265-269, October, 1993. 相似文献
158.
Z. -G. Fan Y. -X. Zhuang G. Yang R. Shao G. -F. Zhang 《Journal of Alloys and Compounds》1993,200(1-2):33-36
The oxygen absorption process in highly aligned YBa2Cu3Ox samples in air and in pure oxygen was studied at several constant temperatures. The process can be expressed in two steps, a chemical reaction controlled step and a diffusion controlled step. The kinetic equations are as follows respectively:
(1 − at) ln(1 − at) + at = kDt
The activation energy was calculated using an Arrhenius equation. The technical conditions of heat treatment for oxygen absorption of highly aligned YBa2Cu3Ox crystals are discussed. 相似文献
159.
A novel vector algorithm for Reed-Muller (RM) expansions is proposed which can save as many as a factor of 2n-1 memory elements compared with previous matrix algorithms 相似文献
160.
I. P. Borovinskaya T. P. Ivleva V. E. Loryan K. G. Shkadinskii 《Journal of Engineering Physics and Thermophysics》1993,65(4):988-990
A mathematical model of dissolution of gas in a metal is suggested with account of phase formation in accordance with the phase constitution diagram (PCD). The stage-by-stage saturation process to the final product formation is shown for an individual particle, through which a reaction wave passes, depending on the diffusion permeability of the metal and solubility conditions that obey Sieverts's law. The effect of the filtration supply of the oxidant to the reaction zone and the process exothermicity on the course of the process is shown.Institute of Structural Macrokinetics, Russian Academy of Sciences, Chernogolovka, Russia. Translated from Inzhenerno-Fizicheskii Zhurnal, Vol. 65, No. 4, pp. 447–450, October, 1993. 相似文献