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41.
Sylvia Paletschek 《NTM》2011,19(2):169-189
42.
The relationship between moisture content and equilibrium relative humidity (e.r.h.) measured by a dew-point method, was determined over the range 30–90% r.h. for dried peas, shelled almonds and lupins at 15, 25 and 35°C. For dried peas the e.r.h. relationship was conventional, and at 70% r.h. and 25°C the equilibrium moisture contents were 14.8% when desorbing and 14.3% when adsorbing moisture. The relationship for three varieties of almonds was unusual in that there was little hysteresis between adsorption and desorption. The mean moisture content of the two, in equilibrium with 70% r.h. at 25°C was 5.9% for Moroccan sweet, 6.4% for Moroccan bitter and 6.8% for Californian sweet almonds. With dried peas and almonds the e.r.h. increased with temperature, and the moisture contents determined before and after e.r.h. determination were similar, which has been usual with stored products previously studied. However when the moisture of lupins was raised above 11% by adding water as a liquid, the moisture content after e.r.h. determination at 35°C was apparently lower than it had been just previously following e.r.h. determination at the lower temperatures. This implied loss of moisture was not detected when water was added in the vapour phase. At 70% r.h. and 25°C the equilibrium moisture contents were 12.3% when adding liquid water and 13.0% when water was added in the vapour phase. 相似文献
43.
Fisher Dennis G.; Kuhrt-Hunstiger Teresa I.; Orr Sylvia M.; Davis Dawn C. 《Canadian Metallurgical Quarterly》1999,13(1):33
Although drug users' self-report has provided data for much of the published literature about drug use, little is known about self-report validity when participants are asked about diseases that are associated with drug abuse, such as hepatitis. Injecting drug users and crack cocaine smokers (N?=?669) were recruited in Anchorage, Alaska, and asked whether they had been diagnosed previously with hepatitis B. These self-report data were compared to various hepatitis B and C seromarkers as measures of validity of self-report expressed as sensitivity and specificity. Results indicate that although test-retest reliability for self-report is high (.905) and specificity is high (96.06% for hepatitis C virus, or HCV), sensitivity is low (23.74% for HCV). Thus, because of its low sensitivity, self-report of hepatitis should be used only as a prevalence estimate lower bound. More than half of the drug users who had contracted hepatitis had never been told that they were infected. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
44.
Orsino Oliveira Filho Jose Antonio Cardoso Darcy Ramalho de Mello Rogerio Magalhges de Azevedo Sylvia G Carvalho 《高电压技术》2011,37(11):2772-2779
Studies based on AC high voltage tests have been done at Cepel to investigate the performance of 800 kV bushar insulators under heavy wetting conditions. Insulators were tested which are now used on si... 相似文献
45.
Rosalía Poyato Sylvia A. Cruz Francisco L. Cumbrera Berta Moreno Eva Chinarro José A. Odriozola 《Journal of Materials Science》2014,49(18):6353-6362
Ce x Zr1?x O2 (x = 0.10, 0.16 and 0.33) nanocrystalline powders were obtained by a two-step synthesis technique and sintered by spark plasma sintering (SPS). As consequence of the reduction of Ce4+ to Ce3+ species by carbon in the graphite environment in SPS, phase assemblies including tetragonal, monoclinic and pyrochlore phases were generated in the ceramics during the sintering process. The electrical conductivity was highly dependent on phase assembly and atmosphere (N2, H2 and O2). A significant decrease in the activation energy was noticed in the ceramics with high pyrochlore content when measuring the conductivity in H2 atmosphere, consequence of the strong reduction promoted in these ceramics during the measurement. Equal conduction behavior with similar activation energy was observed in all the ceramics when measuring in O2 atmosphere. 相似文献
46.
Elahe Nezami Jennifer Unger Sylvia Tan Caitlin Mahaffey Anamara Ritt-Olson Steve Sussman Selena Nguyen-Michel Lourdes Baezconde-Garbanati Stan Azen C Anderson Johnson 《Nicotine & tobacco research》2005,7(2):243-248
Numerous studies have shown associations between smoking and depression, but the generalizability of the relationship across ethnic groups remains unknown. The present study assessed the association between depression and smoking intention and experimentation among adolescents from four ethnic groups in the Los Angeles area-Chinese/Chinese American, Latino/Hispanic, Persian/Iranian, and White. Over 800 7th graders in the Los Angeles area completed measures of depressive symptoms, experimentation with smoking, intention to smoke, and sociodemographic covariates. Chinese/Chinese American students had the lowest levels of depressive symptoms, whereas Latinos/Hispanics had the highest levels. Latinos/Hispanics also were the most likely to intend to smoke in the next year and were the most likely to have started experimenting with cigarette smoking. Depressive symptoms were significantly associated with intention to smoke even after controlling for language use acculturation, socioeconomic status, gender, and ethnicity. The association between depressive symptoms and intention to smoke did not vary significantly across ethnic groups. These results indicate that the association between depressive symptoms and adolescent smoking generalizes across diverse ethnic groups. 相似文献
47.
Kemenoff Sylvia; Worchel Frances; Prevatt Bruce; Willson Victor 《Canadian Metallurgical Quarterly》1995,9(4):446
The authors compared the effectiveness of video feedback to verbal feedback within the context of Milan Systemic family therapy. Ten families were randomly assigned to either the video- or verbal-feedback condition, resulting in 16 participants in each condition. Families engaged in 5 wks of family therapy, which included either verbal or video feedback on a family interaction task. Changes from pretreatment to posttreatment were analyzed for several problem-related and family variables. Results indicated significant pretreatment posttreatment (controlling for family) interactions for responsibility for the problem and family adaptability. Support was found for the therapeutic effects of video feedback within Milan Systemic therapy. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
48.
DATA AUGMENTATION AND DYNAMIC LINEAR MODELS 总被引:5,自引:0,他引:5
Abstract. We define a subclass of dynamic linear models with unknown hyperpara-meter called d -inverse-gamma models. We then approximate the marginal probability density functions of the hyperparameter and the state vector by the data augmentation algorithm of Tanner and Wong. We prove that the regularity conditions for convergence hold. For practical implementation a forward-filtering-backward-sampling algorithm is suggested, and the relation to Gibbs sampling is discussed in detail. 相似文献
49.
Michael K. Cinibulk Gareth Thomas Sylvia M. Johnson 《Journal of the American Ceramic Society》1992,75(8):2044-2049
The oxidation behavior and microstructure of the oxidized surfaces of RE2 Si2 O7 –Si3 N4 ceramics were investigated. The high oxidation resistance of these materials at 1400°C is attributed to the minimization of amorphous phases via devitrification to disilicates that are in equilibrium with SiO2 , the oxidation product of Si3 N4 . Crystals of RE2 Si2 O7 grew out of the surface silicate in prefered orientations that were dictated by crystal structure. The morphology of the microstructure of the oxidized surfaces was shown to be partially dependent on the concentration of impurities; the presence of Ca was found to coincide with the growth of Gd2 Si2 O7 and Dy2 Si2 O7 crystals with high aspect ratios. 相似文献
50.
A new training programme for US Government officials features simulations that require them to reach across normal bureaucratic boundaries to rehearse actual responses to real-life overseas emergencies. The simulations use a planning template that builds on lessons learned from recent, non-traditional, civil-military and humanitarian operations. The programme aims to help officials from many different parts of the government improve their capacity to coordinate inter-agency responses by institutionalizing advance planning among those most likely to be involved in any US action. A discussion-capture software package developed at the War Gaming and Simulation Centre that incorporates the planning template facilitates this process and supports the training goals. 相似文献