The mechanics of the delamination and spelling of compressed films or coatings has been analyzed using a combination of fracture mechanics and post-buckling theory. It is demonstrated that the delamination of pre-compressed films only occurs if the film buckles, whereupon a stress intensification develops at the buckle perimeter. The associated stress intensity depends on the magnitude of the prestress and the film thickness. Conversely, the delamination of indented coatings occurs without buckling and the stress intensity in this instance depends on the indentation volume, the film thickness and the radius of the delamination. Preliminary attempts have also been made to predict critical spall conditions, following the incidence of buckling.
Abstract : A state-of-the-art, metal-organic chemical vapor deposition (MOCVD) system was acquired and successfully installed. The instrumentation is capable of growth of group-III nitride alloys with control down to the atomic level. The new system has been used to grow novel gallium nitride nanowires, including gallium nitride/indium-gallium nitride/p-type gallium nitride core/shell/shell heterostructures. Structural measurements demonstrate the successful growth of these new nanomaterials, and moreover, physical measurements demonstrate that these new nanowire heterostructures enable high-efficiency blue nanoscale light-emitting diodes.
Empirical evaluation has for many years been utilised to validate theories in other science disciplines. One of the first well-known reported examples of empirical evaluation occurred when Galileo wanted to prove that the rate of descent of objects was independent of their mass. This would disprove a theory put forward by Aristotle that the rate of descent is directly proportional to their weight. To prove his theory Galileo dropped two balls made from the same material but different masses from the top of the Tower of Pisa. When the experiment was performed Galileo's theory was proved correct through the empirical evidence collected. What this story demonstrates is the importance of empirical validation to verify or disprove theories and hypotheses. The purpose of this chapter is to emphasise the importance and difficulties of empirical evaluation in the domain of SPLE.
ADVERTISEMENT RETURN TO ISSUEPREVArticleNEXTLarge-scale ATP-requiring enzymic phosphorylation of creatine can be driven by enzymic ATP regenerationYen-Shiang Shih and George M. WhitesidesCite this: J. Org. Chem. 1977, 42, 25, 4165–4166Publication Date (Print):December 1, 1977Publication History Published online1 May 2002Published inissue 1 December 1977https://pubs.acs.org/doi/10.1021/jo00445a046https://doi.org/10.1021/jo00445a046research-articleACS PublicationsRequest reuse permissionsArticle Views328Altmetric-Citations32LEARN ABOUT THESE METRICSArticle Views are the COUNTER-compliant sum of full text article downloads since November 2008 (both PDF and HTML) across all institutions and individuals. These metrics are regularly updated to reflect usage leading up to the last few days.Citations are the number of other articles citing this article, calculated by Crossref and updated daily. Find more information about Crossref citation counts.The Altmetric Attention Score is a quantitative measure of the attention that a research article has received online. Clicking on the donut icon will load a page at altmetric.com with additional details about the score and the social media presence for the given article. Find more information on the Altmetric Attention Score and how the score is calculated. Share Add toView InAdd Full Text with ReferenceAdd Description ExportRISCitationCitation and abstractCitation and referencesMore Options Share onFacebookTwitterWechatLinked InRedditEmail Other access optionsGet e-Alertsclose Get e-Alerts