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91.
A low-abundance form of water, H(2)(17)O, was enriched from 0.04% to ~90% by slow evaporation and fractional distillation of tap water. The density and refractive index for H(2)(17)O are reported. Gas chromatography-mass spectrometry (GC-MS) of (16)O- and (17)O-1-hexanols and their trimethyl silyl ethers and of (16)O- and (17)O-hexamethyl disiloxanes was used to determine the percentage of (17)O enrichment in the H(2)(17)O. Furthermore, the chemical shifts of labeled and nonlabeled water dissolved in CDCl(3) differed sufficiently that we could verify the enrichment of H(2)(17)O. (17)O hexanol was synthesized by the reaction of iodohexane with Na(17)OH. (17)O-Labeled trimethylsilanol and (17)O-labeled hexamethyldisiloxane were prepared by the reaction of H(2)(17)O with bis(trimethylsilyl)trifluoroacetamide (BSTFA). To generate standards for (17)O NMR, H(2)(17)O(2), and (17)O camphor were prepared. H(2)(17)O was electrolyzed to form (17)O-labeled hydrogen peroxide which was quantified using two colorimetric assays. (17)O-Labeled camphor was prepared by exchanging the ketone oxygen of camphor using H(2)(17)O. The (17)O-labeled compounds were characterized using (17)O, (1)H, and (13)C NMR and GC-MS. While we were characterizing the labeled camphor, we also detected an unexpected oxygen exchange reaction of primary alcohols, catalyzed by electrophilic ketones such as camphor. The reaction is a displacement of the alcohol OH group by water. This is an example of the usefulness of (17)O NMR in the study of a reaction mechanism that has not been noticed previously. 相似文献
92.
Caitlyn C. Cook Erika J. Fong Johanna J. Schwartz Dominique H. Porcincula Allison C. Kaczmarek James S. Oakdale Bryan D. Moran Kyle M. Champley Charles M. Rackson Archish Muralidharan Robert R. McLeod Maxim Shusteff 《Advanced materials (Deerfield Beach, Fla.)》2020,32(47):2003376
Volumetric additive manufacturing (VAM) forms complete 3D objects in a single photocuring operation without layering defects, enabling 3D printed polymer parts with mechanical properties similar to their bulk material counterparts. This study presents the first report of VAM-printed thiol-ene resins. With well-ordered molecular networks, thiol-ene chemistry accesses polymer materials with a wide range of mechanical properties, moving VAM beyond the limitations of commonly used acrylate formulations. Since free-radical thiol-ene polymerization is not inhibited by oxygen, the nonlinear threshold response required in VAM is introduced by incorporating 2,2,6,6-tetramethyl-1-piperidinyloxy (TEMPO) as a radical scavenger. Tuning of the reaction kinetics is accomplished by balancing inhibitor and initiator content. Coupling this with quantitative measurements of the absorbed volumetric optical dose allows control of polymer conversion and gelation during printing. Importantly, this work thereby establishes the first comprehensive framework for spatial–temporal control over volumetric energy distribution, demonstrating structures 3D printed in thiol-ene resin by means of tomographic volumetric VAM. Mechanical characterization of this thiol-ene system, with varied ratios of isocyanurate and triethylene glycol monomers, reveals highly tunable mechanical response far more versatile than identical acrylate-based resins. This broadens the range of materials and properties available for VAM, taking another step toward high-performance printed polymers. 相似文献
93.
It has been an extremely interesting, although occasionally hectic, experience working together on what became a truly collaborative, three-way communication effort among authors, reviewers, and editors. This collection of papers, thematically arranged, will be seconded by a group of papers dealing with roots and precursors of social psychology and its development, in applied contexts, to appear later in 1992 in a special issue of the French sociological journal Sociétés Contemporaines. The original papers at the conference were generally limited to 7 pages. Our international group of authors (including a large Canadian delegation) prepared them for publication, received feedback from the reviewers and editors and continued reworking their papers. Together, we pondered what positive, concrete steps could be suggested to improve the papers as to their scholarly accuracy, clarity of argument, rigour of interpretation, and communicability to the journal's readers--for the most part non-specialists in the area of the history of social psychology. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
94.
Explores several questions relating to historical inquiry in the field of social psychology. During its Golden Age, 1945–1970, social psychology was busy defining different fields and paradigms, building theories, and verifying hypotheses; there was little time and need for reflection. The 1970s saw an era of doubts, critique and crisis, during which the constituted knowledge bases were undermined on a number of fronts: methodological, ethical, and theoretical. Examples of how critical history may serve a heuristic function for social psychology are given. The question of how to conduct historical inquiry is addressed, even for as problematic an object as social psychology's development in France. (French abstract) (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
95.
Zuroff David C.; Fournier Marc A.; Patall Erika A.; Leybman Michelle J. 《Canadian Metallurgical Quarterly》2010,51(1):58
A comprehensive evolutionary personality psychology can be developed by identifying individual differences within each of the evolved systems that regulate social behaviour. We developed a questionnaire measure of social rank style, defined as individual differences in preferred strategies for pursuing, defending, and, when necessary, relinquishing social rank. The 17-item Rank Style with Peers Questionnaire (RSPQ) comprises three nearly independent scales: dominant leadership, coalition-building, and ruthless self-advancement. A series of studies demonstrated that: (a) the RSPQ’s, factor structure is robust; (b) the three rank style variables are not redundant with the five-factor traits or adult attachment styles; (c) they are related in theoretically expected ways to adjustment outcomes, to agentic and communal interpersonal behaviours, and to social reputations; (d) they predict group and individual performance outcomes relevant to organisational psychology; and (e) they are related in theoretically expected ways to psychopathology, including social anxiety disorder and depressive symptoms. Future directions for research on social rank styles and prospects for an evolutionary personality psychology are discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
96.
Burns John W.; Quartana Phillip J.; Elfant Erin; Matsuura Justin; Gilliam Wesley; Nappi Carla; Wolff Brandy; Gray Erika 《Canadian Metallurgical Quarterly》2010,10(6):755
Unlike most people, those who are characterized by a repressive coping style report high levels of physical (sensory) pain but low levels of emotional distress (affective pain), which is a discrepancy that may suggest a “conversion” process. In two studies, we tested an attention allocation model, proposing that repressors direct attention away from threatening negative affective information and toward nonthreatening physical pain information during emotionally arousing (painful) situations. In Study 1, 84 participants underwent a cold pressor and then recovered. Repressors reported greater pain during recovery than low- and high-anxious participants, but they reported lower distress than high-anxious participants. Repressors reported significant and large discrepancies between high pain and low distress, whereas these differences were less pronounced for other groups. In Study 2, 77 participants underwent an ischemic pain task while performing a modified dot-probe task with sensory and negative affective pain words as stimuli. Repressors showed increasing biases away from affective pain words and toward sensory pain words as the pain task continued, whereas low- and high-anxious participants did not show these shifts in attention. The results support the notion that conversion among repressors may involve a process by which attention is directed away from emotional distress during noxious stimulation and is focused instead on sensory information from pain. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
97.
Responds to the comments by L. R. Jewett, E. G. Newton, S. Smith, and B. D. Thombs (see record 2010-14873-001) on the current authors' original article, "Avoidant coping as predictor of mortality in veterans with end-stage renal disease" (see record 2009-06704-009). In their commentary, Jewett et al note that oddities often encountered in very small datasets—such as the one used by Wolf and Mori—and, as a result, stronger evidence must be accrued from larger, more robust samples. In this response, Jewett et al acknowledge that theirs is a preliminary study of a small and highly select sample and recognize the limited generalizability of our results. Jewett et al maintain that they do not assert that there should be radical changes in clinical or research programs based on their study results, but instead, suggest that further follow-up would be valuable and that readily available and commonly used assessment and intervention procedures may be appropriate in ameliorating avoidant coping in the endstage renal disease (ESRD) population. At the same time, given the focus on mortality, the risk of doing nothing because the evidence is preliminary far outweighs the minimal costs associated with assessing and addressing avoidant coping, particularly since psychological assessment, including of coping behavior, is part of the standard of practice in this population. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
98.
Nicholls Adam R.; Polman Remco C. J.; Levy Andrew R.; Borkoles Erika 《Canadian Metallurgical Quarterly》2010,17(3):181
This study examines the relationship among global coping self-efficacy, coping, and coping effectiveness within athletes. We hypothesized that there would be a positive association between coping self-efficacy and coping effectiveness, which would be mediated by coping. It was also predicted that coping strategies within the task-oriented coping dimension would be positively associated with coping effectiveness, whereas strategies from the disengagement- and distraction-oriented coping dimensions would be negatively associated with coping effectiveness. Participants were 353 athletes between the ages of 18 and 29 years, who completed a measure of coping self-efficacy the night before they competed, in addition to a measure of the athletes' use of coping strategies and their perceived coping effectiveness, which was completed immediately after the competitive event. Results revealed that higher global coping self-efficacy scores were significantly (r = .33, p 相似文献
99.
100.
Lunkenheimer Erika S.; Dishion Thomas J.; Shaw Daniel S.; Connell Arin M.; Gardner Frances; Wilson Melvin N.; Skuban Emily M. 《Canadian Metallurgical Quarterly》2008,44(6):1737
The authors examined the longitudinal effects of the Family Check-Up (FCU) on parents' positive behavior support and children's school readiness competencies in early childhood. It was hypothesized that the FCU would promote language skills and inhibitory control in children at risk for behavior problems as an indirect outcome associated with targeted improvements in parents' positive behavior support. High-risk families in the Women, Infants, and Children Nutrition Program participated in a multisite preventive intervention study (N = 731) with 3 yearly assessments beginning at child age 2 years. Positive behavior support was measured using 4 indicators derived from at-home observations of parent-child interaction during semistructured tasks. Longitudinal structural equation models revealed that parents in families randomly assigned to the FCU showed improvements in positive behavior support from child age 2 to 3, which in turn promoted children's inhibitory control and language development from age 3 to 4, accounting for child gender, ethnicity, and parental education. Findings suggest that a brief, ecological preventive intervention supporting positive parenting practices can indirectly foster key facets of school readiness in children at risk. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献