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Highly c-axis oriented ZnO films have been deposited onto Si (100) substrates at room temperature (RT) and 750 degrees C using radio-frequency reactive magnetron sputtering. The films have been characterized with X-ray diffraction, atomic force microscopy, and transmission electron microscopy (TEM). It is found that the film deposited at RT has grains with a regular shape while the grains show an irregular shape at 750 degrees C. Both of the films deposited at RT and 750 degrees C have a crystallographic orientation relationship with the Si substrate, [110](Si)//[100](ZnO) and (001)(Si)// (001)(ZnO) with a deviation angle below 3 degrees. Cross-sectional TEM images reveal that both of the ZnO films deposited at RT and 750 degrees C are composed of two layers. The first layer is a ZnO transition layer on the Si substrate and the second is a high c-axis oriented layer above the transition layer. The effects of substrate temperature on the growth behavior of ZnO films are discussed. (C) 2006 Elsevier B.V. All rights reserved.

The purpose of this experiment was to compare S-cone mediated human psychophysical thresholds with in vivo recordings from S-cone excited macaque retinal ganglion cells [1S 2 (L 1 M)] in the presence of luminancemodulated and chromaticity-modulated long-wavelength backgrounds. For psychophysics, increment thresholds were measured for 2°, 3 ms test pulses on a 12°, 2 Hz sine wave background. Test pulse chromaticity was 460 nm. The background was formed by 561 and 645 nm LEDs, either modulated in phase or in counterphase. The time-averaged retinal illuminance was 2500 td, with chromaticity metameric to 588 nm. For electrophysiology, response amplitude to a 9.76 Hz test sine wave was measured on a 0.61 Hz sine wave background, using a 4.7° field. The test was an S-cone isolating (tritan) stimulus. The background was formed by 553 and 636 nm equiluminant LEDs, either modulated in phase or in counterphase. The time-averaged retinal illuminance and chromaticity were 2000 td and 595 nm (for a human observer). The psychophysical data revealed that both chromatic and luminance background modulation resulted in threshold elevations. The electrophysiology revealed that the S 2 (L 1 M) ganglion cells were modulated by the luminance-modulated background, but not by the chromatic-modulated background. © 2000 John Wiley & Sons, Inc. Col Res Appl, 26, S150–S156, 2001

The design and experimental studies of a two-staged explosive magnetic flux compression generator (MFCG) with high inductance load are described in this paper. The first stage of the generator consists of a cylindrical helix and amplifies the current and energy, the second stage carries out impedance transformation to an inductive load of 5-6 pH where an output current of 50-70 kA and an electromagnetic energy of 10-15 kJ is obtained. The pulsed voltage across the load could reach 40-60 kV.

Using reactive radio-frequency magnetron sputtering, epitaxial growth of ZnO film was observed on Si (001) substrate at different temperatures ranging from room temperature to 750°C. The epitaxial relationship was determined to be ZnO(001)‖Si(001) in the direction normal to the surface of the films with a deviated angle less than 3° and ZnO[100]‖Si[110] or ZnO[310]‖Si[110] in the plan view. Based on (2×1) reconstruction of Si (001), a heteroepitaxial model was suggested to discuss the influence of Si (001) substrate on the growth and morphology of ZnO films at different temperatures.

It has been demonstrated that resting coronary vascular resistance is elevated with chronic hypertension and concomitant cardiac hypertrophy. The present study employed a model of 6-week, one-kidney, one wrapped Page hypertension to determine if the ability of the heart to match an increase in oxygen demand with an increase in oxygen supply (coronary blood flow) is impaired, and to determine if these vasoregulatory abnormalities are attributable to inadequate adenosine release. Studies were performed in a pentobarbital anesthetized, open-chest canine preparation using a pericardial infusate method to determine adenosine release. Results showed that dobutamine (a beta-receptor agonist) induced increases in myocardial oxygen consumption (MVO2) over a physiological range (8-30 ml O2 X min-1 X 100 g-1) that were accompanied by an increase in coronary blood flow (CBF) with no change in oxygen extraction. The relationship between MVO2 and CBF was not different between the normotensive (NTC) and hypertensive (RHT) animals. Pericardial infusate adenosine (PI ADO) concentrations were not different for the same MVO2 and CBF, and the relationships for MVO2 vs PI ADO as well as PI ADO vs CBF were unaltered by hypertension. However, the relationship between PI ADO and coronary vascular resistance (CVR) was altered in the RHT group such that a given PI ADO concentration was associated with a significantly higher CVR. These data suggest that, over the range of MVO2 studied, there are no limitations in metabolic regulation of the coronary circulation of RHT animals, and that the higher CVR encountered in the RHT group is not the result of a reduced release of the endogenous vasodilator, adenosine.