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991.
992.
Caner Şimşir Münip Dalgiç Thomas Lübben Andre Irretier Michael Wolff Hans Werner Zoch 《Acta Materialia》2010,58(13):4478-4491
During the heat treatment and the welding of steel components, the interactions between the thermal and phase transformation strains result in cyclic loading of the component, which often results in plastic deformation. Although this has long been a well-known fact, the cyclic hardening behavior of supercooled austenite was not investigated up to now. In this study, tension–compression tests were performed on the supercooled austenite of SAE 52100 ball bearing steel at several temperatures using Gleeble3500® thermomechanical testing machine. The results were compared with conventional hardening models used in heat treatment and welding simulation. The results indicate that the metastable austenite exhibits a complicated cyclic hardening behavior that can only be partially reproduced by commercial simulation software. In the outlook, it is concluded that more complicated cyclic hardening models should be implemented for better prediction of distortion and residual stresses after heat treatment or welding. 相似文献
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This study examined how exaggeration in a biographical film about a political candidate affects attitudes toward the candidate, as well as how this attitudinal effect is contingent on goal‐oriented processing strategies and mediated by suspension of disbelief (SOD), a tolerant audience response to a perceived lack of realism. On the basis of a randomized 2 (portrayal of the candidate: mildly positive vs. exaggerated) by 2 (modal processing strategy: didactic vs. hedonic) factorial experiment, we found an indirect effect for exaggeration on attitude through SOD as a function of processing strategy. Implications of the study findings for narrative persuasion theory and research are discussed. 相似文献
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Ontological analyses have been used in numerous publications to compare existing modelling grammars with an ontology. However, a sound theoretical research framework is still missing. Consequently, working with the results of such ontological analyses is theoretically questionable. Therefore, the aim of this paper is threefold. Firstly, we want to contribute to such a theoretical research framework by formalising the ontological analyses approach as sets of mathematical functions between ontological and modelling grammar constructs. Secondly, on this basis, we derive four formal requirements each ontological analyses must comply with. Thirdly, we analyse whether current state of the art ontological analyses comply with our findings. While the formalisation demonstrates the strengths of the ontological analysis approach we conclude that current analyses have theoretical deficiencies, which lead to serious limitations in their application. Lastly, we demonstrate the usefulness of our formal framework by describing a new application. This application uses two different ontological analyses as input and produces mappings between the modelling grammars used in these analyses as output. 相似文献
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999.
Maged Nessim Suresh K Pandey Liliana Werner Musadiq Mohammed Vinod Kumar 《Contact lens & anterior eye》2008,31(1):47-49
Contact lens deposits have been reported previously with extended wear of soft contact lenses, with proteins, lipids, mucous, and various salts such as chloride, potassium and calcium being deposited on the lens surface [1]. We report an unusual case of precipitates on the surface of a bandage contact lens (BCL) following intensive treatment with topical preservative free artificial tears. Evaluation included microscopic and histochemical analysis of the BCL. We have also reviewed the literature for previous reports of contact lens precipitates. 相似文献
1000.
Eberhard Werner Joseph J. Donovan Elizabeth Barker 《Mine Water and the Environment》2008,27(2):109-121
A series of NaOH solution injection experiments were performed as trials for in situ remediation of an acid-producing surface-mine
spoil. Both 20 and 50% (w/w) concentrated NaOH solutions were employed. While the spoil immediately down-gradient of the injection
wells was neutralized, only about 23% of the introduced Na was recovered at the spring discharge in 3 years of post-injection
monitoring. This rate of transport was far slower than the estimated advection rates in the aquifer, indicating that substantial
retardation of both Na and the associated alkalinity occurred. This retardation is ascribed to: precipitation of alkaline-earth
carbonate hydroxide minerals, as well as metal hydroxide precipitates, consuming injected alkalinity; and reduction of hydraulic
conductivity in the peralkaline (pH > 13) “plume” region due to plugging by reaction products. It is likely that Na and alkalinity
will continue to leak from this plume region for many years, but at too slow a rate to neutralize AMD at current concentrations.
Future injection efforts of this type may be feasible but should use lower concentrations and should be focused further down-gradient,
in closer proximity to the springs, where ground water velocities are higher. 相似文献