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61.
Christopher P. Nemeth 《Cognition, Technology & Work》2007,9(3):127-130
The first special issue in Large-Scale Coordination earlier this year showed the breadth of application research from air
traffic control to the military and multi-agency emergency response. This special issue shows depth of research at large scale
in healthcare. These studies of large-scale coordination examine work between and across groups, beyond earlier conceptions
of social human factors. Revealing the complexity of work domains and the subtle, yet effective, ways that workers negotiate
its challenges opens the way to develop information and communications technology support tools that are grounded in a scientific
understanding. 相似文献
62.
W. Xu K. Daub X. Zhang J.J. Noel D.W. Shoesmith J.C. Wren 《Electrochimica acta》2009,54(24):5727-5738
Surface oxide film growth and conversion processes on carbon steel were studied using a range of electrochemical techniques and ex situ surface analyses. The electrochemical study included (i) cyclic voltammetry as a function of various scan conditions and (ii) 7-day potentiostatic oxidation at a range of potentials while periodically performing Electrochemical Impedance Spectroscopy. Carbon steel surfaces at various stages of electrochemical oxidation were examined by SEM, Raman and X-ray photoelectron spectroscopy (XPS). These studies yield a consistent picture of film formation/conversion processes on carbon steel at pH 10.6, which is different to that reported for basic solutions (pH > 13). Oxide film formation/conversion mechanisms for three potential regions are proposed. In region I (≤−0.6 V vs SCE), the main oxide formed is Fe3O4 which grows via a solid-state process; in region II (−0.5 V ≤ E (vs SCE) ≤ −0.2 V), continuous growth of the Fe3O4 layer is accompanied by its anodic conversion to a more maghemite (γ-Fe2O3)-like phase near, or at, the oxide/solution interface by a similar solid-state mechanism to that described for region I; in region III (0.0 V < E (vs SCE) < 0.4 V), the anodic conversion of this Fe3O4/γ-Fe2O3 oxide to γ-FeOOH leads to a significant structural change, which can lead to film fracture and the introduction of enhanced transport pathways in the film. 相似文献
63.
Natalya V. Likhanova Octavio Olivares-Xometl Noel Nava-Entzana Hector Dorantes 《Corrosion Science》2010,52(6):2088-2097
Ionic liquids with chemical formula 1,3-dioctadecylimidazolium bromide and N-Octadecylpyridinium bromide were synthesized by conventional and microwave-assisted reactions, respectively. Ionic liquids tested as corrosion inhibitors after polarization curves displayed corrosion protection efficiency within 82-88% at 100 ppm for mild steel in a 1 M aqueous solution of sulfuric acid. Standard free energy indicated that corrosion inhibition occurred by a chemical adsorption process. Surface analysis (SEM, EDX) completed by XRD and Mössbauer spectroscopy indicated the presence of carbon species pertaining to inhibitor and corrosion products, which was rationalized in an inhibition mechanism. 相似文献
64.
The traditional psychological approach of studying aggression among schoolchildren in terms of individual differences in aggression and in victimization has been valuable in identifying prevalence rates, risk, and consequences of involvement in aggression. However, it is argued that a focus on aggressor–victim relationships is warranted based on both conceptual and empirical grounds. Such a shift in focus requires modification and integration of existing theories of aggression, and this paper integrates social-cognitive theory and interdependence theory to suggest a new, interdependent social-cognitive theory of aggression. Specifically, this paper identifies points of overlap and different foci between these theories, and it illustrates their integration through a proposed model of the emergence of aggressor–victim interactions and relationships. The paper concludes that expanding consideration to include aggressor–victim relationships among schoolchildren offers considerable theoretical, empirical, and intervention opportunities. (PsycINFO Database Record (c) 2011 APA, all rights reserved) 相似文献
65.
Pepperberg Irene M.; Sandefer Robert M.; Noel Dawn A.; Ellsworth Clare P. 《Canadian Metallurgical Quarterly》2000,114(4):371
Grey parrots (Psittacus erithacus) learn referential English labels when they view and interact with 2 humans who model vocal labeling and who demonstrate referentiality and functionality of a label (I. M. Pepperberg, 1990a). To test if both trainers are necessary, the authors contrasted 2-trainer modeling with training by 1 human who presented targeted labels to a bird in concert with appropriate items, who asked questions, and who would reward attempts at the label with the item. The bird was also tutored by either 1 or 2 interactive humans in conjunction with a conspecific who already used referential labels. Referential labels were learned from multiple live tutors but not a single trainer. Presence of a conspecific enhanced learning compared with single-trainer sessions but did not affect acquisition in 2-human sessions. Specific aspects of paired tutoring seem critical for acquiring referential vocal labels. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
66.
67.
Bjørn Winther‐Jensen Noel Clark Priya Subramanian Richard Helmer Syed Ashraf Gordon Wallace Leone Spiccia Douglas MacFarlane 《应用聚合物科学杂志》2007,104(6):3938-3947
Conducting polymers such as polypyrrole may be useful in smart packaging products, provided application methods can be developed that circumvent the insolubility and infusibility of these materials. Experiments were conducted in five research areas relevant to the application of polypyrrole to nonrigid substrates. The studies reveal that application of polypyrrole from the liquid phase, either by deposition from depleted bulk solution or inkjet printing dispersions, is unlikely to give films as regular as those produced by vapor phase polymerization. Using the latter approach, two potential methods of applying patterned polypyrrole films to nonrigid substrates were developed. The first used hypochlorite to pattern a continuous film of polypyrrole, previously applied by vapor phase polymerization. The second used inkjet printing to apply an oxidant solution, whose pH had been raised with a volatile base, to nonrigid substrates. The higher pH reduced corrosion of the print head, increasing the lifetime of printers exposed to oxidative compounds. The base was subsequently evaporated by heating, and the dried oxidant used as a template for vapor phase polymerization of polypyrrole. This method gave smooth, shiny and adherent polypyrrole films on papers and polyester transparency, with high resolution. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci 104: 3938–3947, 2007 相似文献
68.
Michael G. Pravica Noel A. Guardala Jack L. Price 《Diamond and Related Materials》2009,18(5-8):846-849
Using MeV-range protons to transmute a small fraction of host nuclei into n- or p-type dopants, we have demonstrated a novel method to dope challenging wide bandgap semiconductors. In particular, we have doped isotopically-enriched 13C diamond and AlGaN films using this method focusing on the 13C + 1H → 14N + γ, radiative proton capture resonance at 1.75 MeV and 27Al + 1H → 28Si + γ proton capture resonance at 0.997 MeV. Both samples sustained primarily end-of-range damage which was annealable in AlGaN. We have performed a variety of measurements to characterize the doped samples including Raman spectroscopy, STM, and X-ray diffraction on the doped samples which suggest the viability of IBNTD as a doping method. Calculations indicate that doping layer thicknesses of the order of 10 nm are achievable. Possible doping concentrations using this technique are also estimated. 相似文献
69.
Nemeth J.G. Vargha B. Kollar I. 《IEEE transactions on instrumentation and measurement》2000,49(6):1260-1263
System identification is an inherently iterative process. Yet, limited attempts have been made so far to implement the whole identification loop in a single device. This paper discusses the difficulties of the task and presents a solution based on a Matlab toolbox and a set of virtual instruments. During the identification session, the obtained models may call for refinement or validation by new experiments. Using this integrated software-hardware tool, these subsequent experiments can be accomplished online with the identification procedure. As a demonstration, the modeling of a hairdryer is described. The universal applicability of this solution is believed to be guaranteed by the modular architecture of virtual instrumentation and the general definition of the software interface developed. The interface allows combining Matlab-based identification packages with virtual instruments or pure hardware interfaced to Matlab 相似文献
70.
Voltammetric studies and galvanostatic oxidation results for the electrochemical oxidation of octyl. hexyl, butyl, isobutyl
and benzyl alcohols on hydrated nickel-cobalt oxide electrode in alkaline media are reported. These compounds are oxidised
to their corresponding acids with high efficiency. The electrodes are not contaminated and hence their repeated use for the
oxidation of same or different compounds is possible. Oxidation of benzyl chloride leads to formation of benzyl alcohol, benzaldehyde
along with benzoic acid. 相似文献