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81.
A. L. Hodge C. S. Arnold 《JOM Journal of the Minerals, Metals and Materials Society》1960,12(4):325-330
“How fast and at what cost can open-hearth steel be made?” This paper provides a partial answer by discussing the chemical and thermal effects of using high oxygen input rates from the time hot metal has been added until the furnace is ready to tap. 相似文献
82.
Self-esteem of 350 7th graders from open and traditional elementary schools was measured according to the Coopersmith Self-Esteem Inventory and corresponding Coopersmith Behavior Rating Form. The 7 open and 8 traditional classes used in the study were rated according to the Walberg-Thomas Scales (a teacher questionnaire and classroom observation scale) and were found to be significantly different treatment groups. No differences in self-esteem were found between the groups, however, nor were main effects found for socioeconomic status, IQ, or sibling position. The sex factor did show significant difference. Findings indicate that skepticism is necessary regarding claims that the open school format fosters self-esteem. Additional data that use consistent measuring instruments and vary S populations are needed. (22 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
83.
Oliver Franke Mathias Göken Andrea M. Hodge 《JOM Journal of the Minerals, Metals and Materials Society》2008,60(6):49-53
Mechanical testing of biological materials is a continuously developing field that requires the testing of hierarchical structures.
This article discusses the use of nanoindentation as a valuable tool for assessing multiple length scales as well as parts
of complex biological systems. The multiple issues that must be accounted for while testing biological materials are also
presented. In addition, dynamic nanoindentation is introduced as a method for testing soft tissues under optimized loading
frequencies encountered in everyday movements. 相似文献
84.
85.
Examined the effects of training method (programmed vs individual supervision) and supervisor experience (peer vs professional) on the learning of empathy. Eight supervisors (4 professional and 4 peer) were assigned 3 Ss in each of 3 groups: individually supervised, programmed, and control. Ss listened to 3 sets of recorded client statements and responded as counselors. The 2 experimental groups received training after the 1st and 2nd sets. The control group received no training. An analysis of recorded responses indicated that the individually supervised Ss achieved a significantly higher level of empathy than the controls. Ss receiving programmed training were intermediate in learning between individually supervised and control Ss. Supervisor experience was not found to be a significant factor as no posttraining differences were noted between professional and peer-trained groups. This result supports the use of peers in such interpersonal skills training. (22 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
86.
R. Collé Zhichao Lin F. J. Schima P. A. Hodge J. W. L. Thomas J. M. R. Hutchinson B. M. Coursey 《Journal of research of the National Institute of Standards and Technology》1995,100(1):1-36
Carrier-free 209Po solution standards have been prepared and calibrated. The standards, which will be disseminated by the National Institute of Standards and Technology as Standard Reference Material SRM 4326, consist of (5.1597 ±0.0024) g of a solution of polonium in nominal 2 mol · L−1 hydrochloric acid (having a solution density of (1.031±0.004) g · mL−1 at 22 °C) that is contained in 5 mL flame-sealed borosilicate glass ampoules, and are certified to contain a 209Po alpha-particle emission rate concentration of (85.42±0.29) s−1 · g−1 (corresponding to a 209Po activity concentration of (85.83 ±0.30) Bq · g−1) as of the reference time of 1200 EST 15 March 1994. The calibration was based on 4πα liquid scintillation (LS) measurements with two different LS counting systems and under wide variations in measurement and sample conditions. Confirmatory measurements by 2πα gas-flow proportional counting were also performed. The only known radionuclidic impurity, based on α- and photon-emission spectrometry, is a trace quantity of 208Po. The 208Po to 209Po impurity ratio as of the reference time was 0.00124 ±0.00020. All of the above cited uncertainty intervals correspond to a combined standard uncertainty multiplied by a coverage factor of k = 2. Although 209Po is nearly a pure α emitter with only a weak electron capture branch to 209Bi, LS measurements of the 209Po a decay are confounded by an a transition to a 2.3 keV (Jπ= 1/2−) level in 205Pb which was previously unknown to be a delayed isomeric state. 相似文献
87.
Candidate mitigative strategies for the management of in-vessel events during the late phase (after-core degradation has occurred) of postulated boiling water reactor (BWR) severe accidents were considered at Oak Ridge National Laboratory (ORNL) during 1990. The identification of new strategies was subject to the constraint that they should, to the maximum extent possible, make use of the existing equipment and water resources of the BWR facilities, and not require major equipment modifications or additions. As a result of this effort, two of these candidate strategies were recommended for further assessment. The first was a strategy for containment flooding to maintain the core and structural debris within the reactor vessel in the event that vessel injection cannot be restored to terminate a severe accident sequence. The second strategy pertained to the opposite case, for which vessel injection would be restored after control blade melting had begun; its purpose was to provide an injection source of borated water at the concentration necessary to preclude criticality upon recovering a damaged BWR core. Assessments of these two strategies were performed during 1991 and this paper provides a discussion of the motivation for and purpose of these strategies, and the potential for their success. 相似文献
88.
CJ Hodge SC Huckins NM Szeverenyi MM Fonte JG Dubroff K Davuluri 《Canadian Metallurgical Quarterly》1998,89(5):769-779
OBJECT: Functional magnetic resonance (fMR) imaging was performed in human volunteers to determine the lateral perisylvian cortical areas activated by innocuous cutaneous stimulation. METHODS: Eight volunteers who underwent 53 separate experiments form the basis of this report. Eight contiguous coronal slices were obtained using echoplanar fMR imaging techniques while participants were at rest and while somatosensory activation stimuli consisting of vibration or air puffs were delivered to various body areas. The data were analyzed using Student's t-test and cluster analysis to determine significant differences between the resting and activated states. The findings were as follows: the areas in the lateral cortex activated by the stimuli were the primary sensory cortex (SI), the second somatosensory area (SII), the insula, the superior parietal lobule, and the retroinsular parietal operculum (RIPO). Somatotopy was demonstrable in SI but not in the other areas identified. There was a surprisingly low correlation between the amount of cortex activated in the various areas, which could mean separate inputs and functions for the areas identified. The highest correlation was found between activity in SII and RIPO (0.69). CONCLUSIONS: The authors maintain that fMR imaging can be used to identify multiple lateral somatosensory areas in humans. Somatotopy is demonstrated in SI but not in the other lateral cortical sensory areas. The correlations between the amounts of cortex activated in the different lateral sensory areas are low. Recognition of the multiple lateral sensory areas is important both for understanding sensory cortical function and for safe interpretation of studies designed to identify the central sulcus by activating SI. 相似文献
89.
Acenaphthylene was homopolymerized, was copolymerized with divinylbenzene, and was copolymerized with both styrene and divinylbenzene using free radical initiated suspension polymerizations. The acenaphthyl residues in these polymers were more reactive to electrophiles than the phenyl residues in polystyrenes. Thus, bromo, chloro, and iodo groups were introduced using reaction conditions under which polystyrenes did not react. Other groups introduced were sulphonic acid, nitro, 2-chlorobenzoyl, carboxylic acid via cleavage of 2-chlorobenzoyl or via direct metalation then reaction with carbon dioxide, chloromethyl, and formyl. 相似文献
90.