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101.
The thermionic emission behavior of randomly oriented polycrystalline osmium was investigated. Osmium exhibited a low thermionic
work function of 4.68 eV at 1800 K which increased rapidly to 5.21 eV at 2600 K. The high temperatures and low pressures of
these tests were designed to minimize any residual gas interactions with the sample surface. Still, the possibility that residual
gases had some effect on the measured work function was not altogether ruled out. An allotropic phase transformation was considered
as a possible explanation for the varying work function; however, X-ray diffraction experiments could not substantiate a new
high-temperature phase. 相似文献
102.
Alexander Ralph A.; Scozzaro Michael J.; Borodkin Lawrence J. 《Canadian Metallurgical Quarterly》1989,106(2):329
This article statistically and empirically examines the chi-square test of homogeneity of effect sizes when that test is applied to correlation coefficients and to their Fisher's r-to-z transformation equivalents. Shows that the test on untransformed rs has excessively high Type I error rates as a result of distribution characteristics of r but that the test performs nominally for Fisher's r-to-z transformation values. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
103.
Kirisci Levent; Vanyukov Michael; Dunn Marija; Tarter Ralph 《Canadian Metallurgical Quarterly》2002,16(4):290
This study examined the psychometric characteristics of an index of substance use involvement using item response theory. The sample consisted of 292 men and 140 women who qualified for a Diagnostic and Statistical Manual of Mental Disorders (3rd ed., rev.; American Psychiatric Association, 1987) substance use disorder (SUD) diagnosis and 293 men and 445 women who did not qualify for a SUD diagnosis. The results indicated that men ha4 a higher probability of endorsing substance use compared with women. The index significantly predicted health, psychiatric, and psychosocial disturbances as well as level of substance use behavior and severity of SUD after a 2-year follow-up. Finally, this index is a reliable and useful prognostic indicator of the risk for SUD and the medical and psychosocial sequelae of drug consumption. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
104.
Whalen Carol K.; Jamner Larry D.; Henker Barbara; Delfino Ralph J. 《Canadian Metallurgical Quarterly》2001,20(2):99
Surveys and electronic diaries were used to examine depressive and externalizing dispositions as they relate to smoking and moods in 170 early adolescents. Negative moods were prevalent, with anger and anxiety reported on 26%–60% and sadness on 16%–40% of occasions. The risk of smoking, urges to smoke, and alcohol intake were elevated in teens with aggressive and depressive dispositions, as were diary reports of feeling hassled, angry, and sad. Girls high in depression and aggression also reported more anxiety, stress, and fatigue and less happiness and well-being than did their peers. For boys, depression seemed to dampen the elevated smoking risks associated with externalizing behaviors. Discussion focuses on gender differences in personality–smoking linkages, adolescent negative affectivity, the unique contributions of survey and diary methods, and the promise of targeted preventive interventions such as affect regulation training. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
105.
Uniqueness and convergence of solutions to average run length integral equations for cumulative sum and other control charts 总被引:2,自引:0,他引:2
The Average Run Length (ARL) is the most frequently used performance measure for selecting and designing Cumulative SUM (CUSUM) as well as other control charts. The derivation of a closed form expression for the ARL of a CUSUM chart, in terms of its design parameters, is intractable. The ARL is often computed as a numerical solution to an integral equation. In this paper, we establish that the ARL is the unique solution to the integral equation under some weak regularity conditions. We prove that numerical algorithms based on Gauss-Legend re and Simpson quadratures provide accurate approximations to the ARL. We develop the proof by establishing the convergence of numerical approximations to the unique solution of the integral equation. Finally, we demonstrate that the integral equation approach and the theory established in this paper easily extend to other control schemes. In particular, we consider an example with a Shewhart chart with correlated observations from an AR(I) process. 相似文献
106.
The anteromedial temporal lobe has been found to participate in processing emotion, but there are unresolved discrepancies in the literature. To address this issue, the authors investigated recognition of emotion from faces and from prosody in 26 participants with unilateral temporal lobectomy (15 left, 11 right) and in 50 brain-damaged controls. Participants with right, but not left, temporal lobectomy did significantly worse in recognizing fear from facial expressions. There were no group differences in recognizing emotional prosody. Neither IQ nor basic perceptual function accounted for task performance; however, there was a moderate negative correlation between extent of amygdala damage and overall performance. Consistent with some prior studies, these findings support a role for the right anteromedial temporal lobe (including amygdala) in recognizing emotion from faces but caution in drawing conclusions from small group samples. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
107.
J. M. Florence F. W. Glaze C. H. Hahner Ralph Stair 《Journal of the American Ceramic Society》1948,31(12):328-331
A study has been made of the transmittance of near-infrared energy by a number of binary glasses. Of the systems studied, the lithia-silica and lead oxide-silica glasses were found to have the highest transmittance of energy in the range of wave lengths from 3.0 to 5.0 microns. The transmittance of lithia-silica glass is compared with that of the other alkali-silica glasses. Values of transmittance are given for lead silicate glasses of higher lead content than previously reported in the literature. 相似文献
108.
109.
Laura K. Palmer Beverly A. Baptiste John C. Fester Justin C. Perkins Ralph L. Keil 《Yeast (Chichester, England)》2009,26(12):655-661
The molecular mechanisms of action of volatile anaesthetics remain unknown despite clinical use for over 150 years. While many effects of these agents have been characterized, clear insight into how these effects relate to the physiological state of anaesthesia has not been established. Volatile anaesthetics arrest cell division in Saccharomyces cerevisiae in a manner that parallels the anaesthetic actions of these drugs in mammals. To gain additional insight into the cellular activities of these drugs, we isolated genes that, when present on multi‐copy plasmids, render S. cerevisiae resistant to the volatile anaesthetic isoflurane. One of these genes, RRD1, encodes a subunit of the Tap42p–Sit4p–Rrd1p phosphatase complex that functions in the target of rapamycin complex 1 (TORC1) signalling pathway. In addition, we show that mutations in two other genes encoding components of the TORC1 pathway, GLN3 and URE2, also affect yeast anaesthetic response. These findings suggest that TORC1‐mediated signalling is involved in cellular response to volatile anaesthetics in S. cerevisiae. Copyright © 2009 John Wiley & Sons, Ltd. 相似文献
110.