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61.
R. Gran Olsson 《Archive of Applied Mechanics (Ingenieur Archiv)》1937,8(6):449-452
Zusammenfassung Mit Hilfe der Differentialgleichung für die Durchbiegung einer Kreisplatte unter gleichmäßigem, radialem Druck und ihrer bekannten Lösung wird die Knickspannung für den Fall eines unverschieblich eingespannten Außenbzw. Innenrandes und eines frei verschieblich eingespannten Innen- bzw. Außenrandes angegeben. Diese Fälle werden mit der Knickung eines rechteckigen Plattenstreifens im Eulerschen Fall verglichen, wobei die Breite des Plattenstreifens gleich dem Unterschied des Platten- und des Bohrungshalbmessers gesetzt wird. An Hand der Tabelle 2 ergibt sich daraus eine sehr einfache Regel für die Berechnung der Knickspannung einer in der angegebenen Weise gestützten und belasteten, dünnen Kreisringplatte. 相似文献
62.
R. Gran Olsson 《Archive of Applied Mechanics (Ingenieur Archiv)》1941,12(2):123-132
Zusammenfassung Die Grundgleichung vonK. Federhofer für die Ausbiegung einer nur am Au\enrand gedrückten Kreisringplatte bei kräftefreiem Innenrand wird darauf hin untersucht, für welche Exponentenn des Plattenprofilsh=c r
n
eine Integration mit Hilfe der Whittakerschen Funktion möglich ist. Au\er den durch Zylinderfunktionen bereits behandelten Fällenn=0 undn=(5–)/6, ergibt sich je eine Schar von hyperbolischen und parabolischen Profilen, wobei der Exponentn von der Querdehnungszahl des Plattenwerkstoffs abhängt. Es werden die Lösungen der Federhoferschen Grundgleichung mit Hilfe der Whittakerschen Funktion explizit hingeschrieben, und in den Fällenn=0 undn=(5–)/6 die Zurückführung auf Zylinderfunktionen gezeigt. Die Knickbedingungen für die drei möglichen Auflagerungen bei querkraftfreiem Innenrand werden aufgestellt. Die numerische Auswertung soll später mitgeteilt werden. 相似文献
63.
A.L. Vasiliev E.A. Stepantsov Z.G. Ivanov E. Olsson K. Verbist G. Van Tendeloo 《Interface Science》1997,5(4):223-230
The structure of the artificial grain boundaries in Al2O3 bicrystals withY3Al5O12 and Y-stabilizedZrO2 (Y-ZrO2) intermediate layers was studiedwith high resolution electron microscopy, electron diffraction and energydispersive X-ray analysis. TheY3Al5O12 intermediate layer wasfound to be polycrystalline with three different orientation relationshipsbetween the 2O3 and theY3Al5O12. The structure of theY3Al5O12/2O3 interfaces is described.Also2O3 bicrystals with an Y-ZrO2/2O3/Y-ZrO2/2O3/Y-ZrO2intermediate layer, prepared at two different temperatures, werestudied.Recry stallization of the intermediate layers occurred during thesolid phase intergrowth of the 2O3 bicrystalsparts and only an Y-ZrO2 layer was found as intermediatelayer. The misorientation between the consecutive Y-ZrO2grains was less than 1.5°. Misfit dislocations and atomic height stepsdecorate the Y-ZrO2/2O3interface. 相似文献
64.
Per Martin Björemark Dr. Susanne Olsson Dr. Theonitsa Kokoli Prof. Mikael Håkansson 《Chemistry (Weinheim an der Bergstrasse, Germany)》2015,21(24):8750-8753
Even though the isolation of tetrahedral stereoisomers usually presents a synthetic challenge, a highly enantioenriched tetrahedral silver complex could be easily accessed by either crystallization or Viedma ripening. The overall preparation may be regarded as an example of absolute asymmetric synthesis. Experimental results indicate that both crystallization and Viedma ripening follow a similar cluster‐controlled mechanism. 相似文献
65.
Peter Olsson 《Wave Motion》1985,7(5):421-445
The problem of a single rigid movable inclusion is solved both for elastostatics and elastodynamic, using the null field approach. It is also shown how the solution can be obtained as the limit of the solution for an elastic inclusion. Numerical results for scattering by a superspheroidal inclusion are given. 相似文献
66.
Nils Carlsson Hanna Gustafsson Christian Thörn Lisbeth Olsson Krister Holmberg Björn Åkerman 《Advances in colloid and interface science》2014
Mesoporous materials as support for immobilized enzymes have been explored extensively during the last two decades, primarily not only for biocatalysis applications, but also for biosensing, biofuels and enzyme-controlled drug delivery. The activity of the immobilized enzymes inside the pores is often different compared to that of the free enzymes, and an important challenge is to understand how the immobilization affects the enzymes in order to design immobilization conditions that lead to optimal enzyme activity. This review summarizes methods that can be used to understand how material properties can be linked to changes in enzyme activity. Real-time monitoring of the immobilization process and techniques that demonstrate that the enzymes are located inside the pores is discussed by contrasting them to the common practice of indirectly measuring the depletion of the protein concentration or enzyme activity in the surrounding bulk phase. We propose that pore filling (pore volume fraction occupied by proteins) is the best standard for comparing the amount of immobilized enzymes at the molecular level, and present equations to calculate pore filling from the more commonly reported immobilized mass. Methods to detect changes in enzyme structure upon immobilization and to study the microenvironment inside the pores are discussed in detail. Combining the knowledge generated from these methodologies should aid in rationally designing biocatalyst based on enzymes immobilized in mesoporous materials. 相似文献
67.
A voltammetric electronic tongue is described that was used for multicomponent analysis of drinking water. Measurements were performed on drinking water from a tap and injections of the compounds NaCl, NaN3, NaHSO3, ascorbic acid, NaOCl and yeast suspensions could be identified by use of principal component analysis (PCA). A model based on partial least square (PLS) was developed for the simultaneously prediction of identification and concentration of the compounds NaCl, NaHSO3 and NaOCl. By utilizing this type of non-selective sensor technique for water quality surveillance, it will be feasible to detect a plurality of events without the need of a specific sensor for each type of event. 相似文献
68.
Peter Olsson 《Wave Motion》2011,48(6):539-549
Recently, some explicit results were obtained regarding non-uniqueness for the traction to displacement maps of bounded elastic bodies in 2D and 3D, under the assumption of an internal kinematic constraint. The approach utilized is that of transformation optics. As the approach could, under the usual continuum assumptions, handle all frequencies without resorting to active materials, it could potentially be directly applied also to time domain problems. In the present paper we cover the extension to the time domain of these recent results in the case of reflection from a composite slab of rather general anisotropy, and derive the required material properties of different slabs with identical reflection properties. In particular we describe how homogeneous and inhomogeneous slabs of very different thicknesses may be indistinguishable with respect to elastic wave reflection properties. It should be noted that the approach retains both the minor and major symmetries of the stiffness tensor, and does not require an anisotropic mass density tensor to be used. 相似文献
69.
70.