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151.
Daniel Röhnert Fritz Phillipp Helfried Reuther Till Weber Egbert Wessel Michael Schütze 《Oxidation of Metals》2007,68(5-6):271-293
The initial stages of the metal-dusting process on Alloy 800 at 620 °C were investigated by light optical microscopy, RAMAN
spectroscopy, atomic-force microscopy, Auger electron spectroscopy, transmission-electron microscopy and electron back-scatter
diffraction. As it turned out the incubation period for metal-dusting is characterized by simultaneous formation of a heterogeneously
growing oxide scale and deposition of carbon. The material surface shows different tarnish colors depending on the substrate-grain
orientation with different susceptibility to the beginning of metal-dusting attack. “Low-index” grains were not attacked within
the times investigated while the other grain orientations showed pitting. Carbon is evidently incorporated into the oxide
scale from the very beginning of exposure with different intensities depending on the underlying substrate-grain orientation
leading to differences in the tarnish colors. As a consequence carbides are formed even underneath “dense” oxide layers. Evidently
metal-dusting attack starts at positions of the oxide scale where “higher carbon concentrations” are present. 相似文献
152.
Douglas H. Taylor Kirk E. Lagory Daniel J. Zaccaro Ronald J. Pfohl R.Dana Laurie 《The Science of the total environment》1985
Trichloroethylene (TCE) is a common contaminant of underground water supplies. To examine the effect of TCE on the developing central nervous system, rats were exposed to TCE throughout gestation until 21 days postpartum via their dams' drinking water. TCE concentrations of 312 mg/l, 625 mg/l and 1250 mg/l were tested. Exploratory behavior was higher in 60- and 90-day old male rats which were exposed to any level of TCE. The effect of TCE-exposure on locomotor activity (running wheel) was also examined in 60-day old males (625 and 1250 ppm exposure groups). Locomotor activity was significantly higher in rats exposed to 1250 ppm TCE. These data suggest that TCE has long-term effects on behaviour. 相似文献
153.
Examined the judgments made by 384 undergraduates and 384 50–74 yr olds of assailant and victim responsibility for a sexual assault. Ss were assigned to 1 of 3 conditions: they viewed slides of an assault, read a passage about the crime, or read the passage and saw photographs of both the assailant and the victim. The rapist was presented as either a well-dressed or poorly dressed young man, and the victim appeared either as a provocative or demure young woman. Ss also learned that the victim either physically resisted or failed to resist the assailant. Young Ss attributed more responsibility to the assailant than did older Ss, and the provocative woman was perceived as more responsible for the victimization than the demure woman. Young Ss attributed greater responsibility to the victim when she resisted the assault of a well-dressed assailant than when she resisted a poorly dressed assailant. Females attributed less responsibility to the demure woman when she was assaulted by a poorly dressed assailant than a well dressed assailant. In contrast to older Ss, young Ss who visually observed the crime held the victim more responsible for her victimization. Results are interpreted in terms of the defensive attribution hypothesis of E. Walster (see record 1966-02829-001) and the discounting principle of attribution presented by H. H. Kelley (see record 1973-24800-001). (French abstract) (31 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
154.
Memorializes E. E. Jones, whose early development of attribution theory, the actor–observer effect, and the correspondence bias as well as later work on self-handicapping, social stigma, and strategic self-presentation are central to modern social psychology. He built graduate programs at Duke and Princeton, trained many influential social psychologists, and received virtually every award in his field. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
155.
The estimate of the population correlation used in the formula for sampling error variance of a correlation is typically the observed correlation, but in meta-analysis the average of the observed correlations can be used. For the case in which there is no variation in the study population correlations or sample sizes and the number of studies is very large, the authors found that use of the average correlation estimator is more accurate than use of the traditional, individual correlation estimator, except in those rare cases in which the uncorrected population correlation is greater than .60. For typical sample sizes, when the uncorrected population correlation is between -.40 and .40, there is virtually no error in the meta-analysis credibility interval based on the average correlation estimator. On the other hand, the amount of the error in the individual correlation estimator is qualitatively important if the sample is 25 or less and the population correlation is less than .40. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
156.
AD Sandler C Schmidt K Richardson J Murray JW Maher 《Canadian Metallurgical Quarterly》1993,114(2):285-93; discussion 293-4
BACKGROUND: An increase in esophageal mucosal blood flow (MBF) may be an important protective mechanism against mucosal injury from noxious agents that are ingested or refluxed. This study investigated the changes in MBF and the regulation thereof after intraluminal application of noxious chemical stimuli. The role, if any, of substance P (SP) and nitric oxide (NO), two potent vasodilatory substances, and the vascular distribution of SP in the distal esophagus were evaluated. METHODS: Esophageal MBF was measured in anesthetized dogs with a laser Doppler flow probe attached to manometry and pH probes. MBF was measured before and after topical application of HCl (2 ml; 1N) or capsaicin (2 ml; 0.5%) in the distal esophagus. The effects on MBF of intraarterial SP and bradykinin were also determined. Pharmacologic antagonists and denervation procedures were used to delineate the mechanisms that regulate MBF. RESULTS: Sequential luminal applications of hydrochloric acid (HCl) or a single application of capsaicin increased MBF (p < 0.01). Topical intraluminal lidocaine blocked the response to capsaicin (p > 0.2) but not to HCl (p < 0.05). Abrupt increases in MBF occurred with intraarterial SP or bradykinin (p < 0.01). Neither atropine nor truncal vagotomy blocked the increase in MBF from these peptides or noxious stimuli. The NO synthesis antagonist NG-nitro-L-arginine methyl ester (L-NAME) blocked the response to bradykinin and attenuated the response to HCl (p < 0.05). NG-nitro-L-arginine methyl ester did not affect the response to SP or capsaicin. A substance P antagonist blocked the effects of both capsaicin (p > 0.6) and SP (p > 0.1) but not that of HCl (p < 0.01) or bradykinin (p > 0.01). CONCLUSIONS: Intraluminal applications of HCl or capsaicin appear to stimulate increases in esophageal MBF by different mechanisms. HCl produces an adaptive response that appears dependent on the paracrine effect of NO. Capsaicin-sensitive neurons mediate vasodilation through SP neurotransmission, independent of extrinsic vagal or cholinergic innervation. 相似文献
157.
Robin Daniel J.; Berthier Neil E.; Clifton Rachel K. 《Canadian Metallurgical Quarterly》1996,32(5):824
Infants were presented with a moving object under 2 lighting conditions to investigate the role of vision in early reaching. The motion of the target object also allowed for an analysis of the infants' ability to use a predictive style of reaching. Infants were tested twice, at 5 and 7.5 months of age, with a moving object in the light and the same object painted with luminescent paint in the dark. Infants successfully contacted the glowing object on about half of their attempts at both ages, although 7.5 month-olds reached more often. Infants also took into account the motion of the target object by aiming their reaches ahead of the object and by reaching with their contralateral hand. These results suggest that proprioceptive feedback and sight of the target allow for successful reaching with limited visual information, even in relatively complex reaching tasks. The infants' success also demonstrates their ability to adapt their movements and reaching strategy to the speed and trajectory of the target object in order to reach predictively. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
158.
The dislocation structures of bulk textured and epitaxial thin film YBa2Cu3O7 superconductors are examined. Correlations between increases in flux pinning and dislocation densities are noted. A model
for flux pinning by individual dislocations is presented. This gives a treatment of strain induced effects and effects of
normal state region interactions. It is shown that the values of pinning predicted are in line with experimental observations. 相似文献
159.
Christian Jennifer L.; O'Leary K. Daniel; Vivian Dina 《Canadian Metallurgical Quarterly》1994,8(1):32
Marital discord and depressive symptomatology have repeatedly been found to be associated, but little is known about variables that influence this relationship. Data were collected from 139 couples seeking marital therapy, and analyses were conducted separately by gender. For wives, lower problem-solving ability, physical aggression by the partner, and 1 relationship belief predicted depressive symptomatology after the variance due to marital discord was removed in regression analyses. In addition to these predictors, less spouse-specific assertiveness, unemployment, and 1 other relationship belief were associated with depressive symptomatology for women after the variance due to marital discord was removed in partial correlation analyses. For men, only lower problem-solving ability added to the prediction of depressive symptomatology. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
160.
D Schmidt KJ Langen H Herzog J Wirths M Holschbach JC Kiwit K Ziemons HH Coenen H Müller-G?rtner 《Canadian Metallurgical Quarterly》1997,24(9):1162-1166
BACKGROUND: Desflurane anesthesia can produce cerebral metabolic depression and increase cerebral blood flow. We evaluated the effect of desflurane on brain tissue oxygen pressure (PO2), carbon dioxide pressure (PCO2) and pH during neurosurgery. METHODS: Following a craniotomy, the dura was opened and a Paratrend 7 sensor, which measures PO2, PCO2, pH and temperature, was inserted into brain tissue. In 6 control patients in group 1, anesthesia was maintained constant with 3% end-tidal desflurane over 60 min, including a 30-min stabilization period. In group 2, 9 patients were ventilated with 3% desflurane under baseline conditions. After a 30-min stabilization period, baseline tissue gases and pH were measured and end-tidal desflurane was increased to 6% and then 9% for 15-min intervals. Mean arterial pressure (MAP) was maintained with intravenous phenylephrine. RESULTS: Under baseline conditions, cardiovascular and brain tissue measures were similar between the 2 groups. Increasing end-tidal desflurane from 3% to 9% produced burst-suppression EEG in all patients and significantly increased tissue PO2 and pH and decreased PCO2. No parameters changed significantly in the control group during steady-state anesthesia. CONCLUSION: These results show that 9% desflurane can improve brain tissue metabolic status before temporary brain artery occlusion if cerebral perfusion pressure is maintained. This may be particularly important in patients with symptoms of ischemia before surgery. 相似文献