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Adams Edwin P. 《Journal of The Franklin Institute》1927,204(4):469-486
(I) Evidence has been given that the so-called permanent electrets of Eguchi are not permanent, but that their polarization decays with the time. At room temperatures this decay is too slow to be observed directly; but it is the decay of the polarization that, at least in part, accounts for the presence of the free charges that are always observed. At higher temperatures the results that have been obtained are consistent with the view that the rate of decay of the polarization increases very rapidly with the temperature; so much so that the polarization may be almost completely destroyed at a temperature which is not high enough to cause any appreciable softening of the waxes that form the substance of the electrets.(2) As is to be expected from Lord Kelvin's hypothesis as to the cause of pyro-electricity, these electrets have been shown to possess the pyro-electric property.(3) The piezo-electric effect, which always accompanies the pyro-electric property, has been shown to be exhibited by these electrets. 相似文献
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Prediction of maximal oxygen uptake in sedentary males from a perceptually regulated, sub-maximal graded exercise test 总被引:2,自引:0,他引:2
The purpose of this study was to assess the validity of predicting the maximal oxygen uptake (VO2(max)) of sedentary men from sub-maximal VO2 values obtained during a perceptually regulated exercise test. Thirteen healthy, sedentary males aged 29-52 years completed five graded exercise tests on a cycle ergometer. The first and fifth test involved a graded exercise test to determine VO2(max). The two maximal graded exercise tests were separated by three sub-maximal graded exercise tests, perceptually regulated at 3-min RPE intensities of 9, 11, 13, 15, and 17 on the Borg ratings of perceived exertion (RPE) scale, in that order. After confirmation that individual linear regression models provided the most appropriate fit to the data, the regression lines for the perceptual ranges 9-17, 9-15, and 11-17 were extrapolated to RPE 20 to predict VO2(max). There were no significant differences between VO2(max) values from the graded exercise tests (mean 43.9 ml x kg(-1) x min(-1), s = 6.3) and predicted VO2(max) values for the perceptual ranges 9-17 (40.7 ml x kg(-1) x min(-1), s = 2.2) and RPE 11-17 (42.5 ml x kg(-1) x min(-1), s = 2.3) across the three trials. The predicted VO2(max) from the perceptual range 9-15 was significantly lower (P < 0.05) (37.7 ml x kg(-1) x min(-1), s = 2.3). The intra-class correlation coefficients between actual and predicted VO2(max) for RPE 9-17 and RPE 11-17 across trials ranged from 0.80 to 0.87. Limits of agreement analysis on actual and predicted VO2 values (bias +/- 1.96 x S(diff)) were 3.4 ml x kg(-1) x min(-1) (+/- 10.7), 2.4 ml x kg(-1) x min(-1) (+/- 9.9), and 3.7 ml x kg(-1) x min(-1) (+/- 12.8) (trials 1, 2, and 3, respectively) of RPE range 9-17. Results suggest that a sub-maximal, perceptually guided graded exercise test provides acceptable estimates of VO2(max) in young to middle-aged sedentary males. 相似文献
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Dennis Adams 《Educational Media International》2013,50(3):158-163
Abstract The article discusses how sections of a video can best be used in the instructional process by activating the minds of students and using their reactions to viewing to produce intellectual action. It gives some suggested schemes for this activity and shows how technological forces can become energies of change. 相似文献
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Your Energy World Published by U.S. Department of Energy Blue Wings Flying by Elizabeth DeHuff Pictures by Dorothea Sierra Addison‐Wesley Publishing Co. Readding, Mass. 01867 Early Childhood Filmstrips Series Part I: About Myself Myself and Other People — Alike and Different My Family and Other Families—Alike and Different Everyone Needs Many Things by Ruth Jaynes, Beatrice Woodbrldge & Nancy Curry Bowmar/Noble Publishers, Inc. 4563 Colorado Los Angeles, CA 90039 “Man and His Gods: An Inquiry Into The Nature of Religions” Published by The Center for Humanities, Inc. 2 Holland Ave. White Plains, NY 10603 Alcohol: Facts, Myths and Decisions Published by Science and Mankind, Inc. Communications Park, Box 200 White Plains, New York 10601 相似文献
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