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91.
A. Ortiz S. Lopez C. Falcony M. Farias L. Cota-Araiza G. Soto 《Journal of Electronic Materials》1990,19(12):1411-1415
Silicon dioxide films have been deposited by Plasma-Enhanced Chemical Vapor Deposition (PECVD) technique using SiCl4 and O2 as reactive materials. Infra-red transmittance, Auger electron spectroscopy analysis, ellipsometry, electrical, and chemical
etch measurements have been used to characterize these films. It is possible to obtain good quality oxides at a substrate
temperature of 200° C using a low flow of reactant gases. High flow of reactant gases results in highly non-homogeneous porous
films. The best oxide films obtained show destructive breakdown at electrical fields above 4 MV/cm and a fixed charge density
of the order of 2.6 × 1011 charges/cm2. 相似文献
92.
In a sample of 247 college students, the contributions of adult attachment orientations and several other boundary regulation variables to measures of self-splitting (i.e., the tendency to report diffuse and chaotic self-experiences) and other-splitting (i.e., the tendency to acknowledge unstable perceptions of and feelings toward one's friends) were explored. Adult attachment orientations and self-other boundary regulation variables, respectively, explained unique variance in each criterion measure. High levels of attachment anxiety and self-concealment and low levels of self-other differentiation contributed most prominently to self-splitting, whereas high attachment anxiety, low emotional reactivity, and high needs for social approval best predicted other-splitting. Implications of these findings for advancing a more delineated understanding of splitting tendencies are discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
93.
For nine short weeks in 1888, Vincent Van Gogh and Paul Gauguin lived and worked together in the city of Arles. Using computer graphics enhancement analyses, some of the paintings they did during this period revealed hidden facial images. One full hidden figure in a painting by Van Gogh and five camouflaged facial images in the works of Paul Gauguin were uncovered using computer graphics techniques. With the exception of one painting by Gauguin, these concealed images have not been previously reported. 相似文献
94.
Jimy Unfried Silgado Edwar Torres Lopez Antonio Jose Ramirez Jorge Giraldo Barrada 《Welding International》2013,27(1):8-14
Susceptibility to hydrogen-induced cracking (HIC) was evaluated in steel welds for quenched and tempered armouring steel of 4.5 mm thickness. The welds were produced using the shielded metal arc welding process with low heat support and AWS E11018M 2.4 mm consumable. The susceptibility to HIC was evaluated by means of an implant test with modified geometry in welded joints with and without preheating being applied, using consumables in ideal stock conditions and exposed to the atmosphere. It was found that the consumable stock conditions were more relevant than preheating in regard to susceptibility to HIC. 相似文献
95.
JS Kim I Lopez PL DiPatre F Liu A Ishiyama RW Baloh 《Canadian Metallurgical Quarterly》1999,52(1):40-44
Immunocytochemical examination for mitochondrial protein and cytochrome oxidase was performed to demonstrate oncocytes in normal adenohypophysis obtained from 28 patients of various age. A small number of solitary large epithelial cells showed intense cytoplasmic granular immunoreactivities for mitochondrial protein and cytochrome oxidase. The proportions of the cells positive for the former and the latter ranged from 0% to 5.9% (mean+/-SD; 1.5+/-1.7%) and from 0% to 4.9% (1.4+/-1.6%), respectively. These cells were either absent or extremely rare in young patients (under 10 years) but tended to increase in number with age (P < 0.0001). On the other hand, the mirror section technique showed that most of these cells were negative for adenohypophysial hormones, but a few of them were faintly positive for: alpha-subunit (8.0%), beta-subunits of follicle-stimulating hormone (4.8%), luteinizing hormone (2.5%), thyroid-stimulating hormone (1.0%), and growth hormone (0.5%), and were negative for prolactin and adrenocorticotropic hormone. We considered that these cells represent oncocytes that exist in varying numbers in normal adenohypophysis. It was suggested that oncocytes in normal adenohypophysis share various common features with tumorous oncocytes of pituitary oncocytomas. 相似文献
96.
Hall Gordon C. Nagayama; Bansal Anita; Lopez Irene R. 《Canadian Metallurgical Quarterly》1999,11(2):186
Meta-analyses were performed on 25 comparative Minnesota Multiphasic Personality Inventory (MMPI) and MMPI-2 studies of 1,428 male African Americans versus 2,837 male European Americans, 12 studies of 1,053 female African Americans versus 1,470 female European Americans, and 13 studies of 500 male Latino Americans and 1,345 male European Americans. Aggregate effect sizes suggest higher scores for ethnic minority groups than for European Americans on some MMPI/MMPI-2 scales and lower scores on others. However, none of the aggregate effect sizes suggest substantive differences from either a statistical or clinical perspective. The MMPI and MMPI-2 apparently do not unfairly portray African Americans and Latinos as pathological. Effect sizes across studies generally did not vary as a function of sociodemographic variables, research setting, or use of the MMPI versus MMPI-2. It is recommended that additional between- and within-ethnic groups psychopathology research continue. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
97.
Calleja A.J. Alonso J.M. Lopez E. Ribas J. Martinez J.A. Rico-Secades M. 《Power Electronics, IEEE Transactions on》1999,14(6):998-1006
A new single-stage high-power-factor electronic ballast based on a flyback converter is presented in this paper. The ballast is able to supply a fluorescent lamp assuring a high-input power factor for the utility line. Other features are lamp power regulation against line voltage variations and low lamp current crest factor, both assuring long lamp life. The ballast is analyzed at steady-state operation, and design equations and characteristics are obtained. Also, a procedure for the ballast design is presented. Finally, simulation and experimental results from a laboratory prototype are shown 相似文献
98.
99.
100.
Contemporary attachment theory is inspiring a burgeoning literature on adult attachment. This literature offers counseling psychology a compelling framework for understanding the healthy and effective self. In this article, the authors review studies probing the cognitive processes, affect self-regulatory dynamics, and relationship behaviors associated with secure (primary) and insecure (secondary) adult attachment strategies. They then offer a portrait of the healthy, effective personality that is consistent with theory and research on adult attachment. Finally, in an effort to understand key characteristics of successful movement toward the healthy and effective self, the authors review empirical extensions of attachment theory to the therapeutic context. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献