Problems of Plane Elasticity for Reinforced Boundaries

1955 ◽  
Vol 22 (2) ◽  
pp. 249-254
Author(s):  
J. R. M. Radok
Keyword(s):  
Plane Elasticity ◽  
Conformal Transformations ◽  
Thin Sheets ◽  
General Method

Abstract Based on N. I. Muskhelishvili’s approach to problems of plane elasticity, a general method has been deduced for the solution of problems of reinforced cutouts in infinitely thin sheets. As an illustration, the circular reinforced hole has been treated in detail and the results have been related to those obtained experimentally and theoretically by other authors. The solution for other shapes of cutouts will be greatly simplified, since full use may be made of the theory of conformal transformations.

scholarly journals A numerical method for the solution of plane crack problems in finite media

1980 ◽  
Vol 3 (4) ◽  
pp. 739-760 ◽  
Author(s):  
P. S. Theocaris ◽  
N. Ioakimidis
Keyword(s):  
Arbitrary Shape ◽  
Plane Elasticity ◽  
The Other ◽  
Straight Crack ◽  
Crack Problems ◽  
Isotropic Elasticity ◽  
Elasticity Problems ◽  
Crack Tips ◽  
Finite Medium ◽  
General Method

A general method for the solution of plane isotropic elasticity crack problems inside a finite medium of arbitrary shape or an infinite medium with holes of arbitrary shape is presented. This method is based on the complex potential approach of plane elasticity problems due to Kolosov and Muskhelishvili [1] and makes no assumption on the way of loading of the cracks and of the other boundaries of the medium.The whole problem is reduced to a complex singular integral equation along the cracks and the other boundaries and the values of the stress intensity factors at the crack tips may be evaluated directly and accurately from the numerical solution of this equation. An application of the method to a circular medium with a straight crack is also made.

Comparison of Acrylamide and Agar Gels by Freeze-Etching

1977 ◽  
Vol 35 ◽  
pp. 606-607
Author(s):  
Russell L. Steere ◽  
Eric F. Erbe
Keyword(s):  
Electron Microscope ◽  
Sodium Hydroxide ◽  
Sodium Hypochlorite ◽  
Chromic Acid ◽  
Distilled Water ◽  
Thin Sheets ◽  
Acid Cleaning ◽  
Agar Gels ◽  
Freeze Etching ◽  
Water Cut

Thin sheets of acrylamide and agar gels of different concentrations were prepared and washed in distilled water, cut into pieces of appropriate size to fit into complementary freeze-etch specimen holders (1) and rapidly frozen. Freeze-etching was accomplished in a modified Denton DFE-2 freeze-etch unit on a DV-503 vacuum evaporator.* All samples were etched for 10 min. at -98°C then re-cooled to -150°C for deposition of Pt-C shadow- and C replica-films. Acrylamide gels were dissolved in Chlorox (5.251 sodium hypochlorite) containing 101 sodium hydroxide, whereas agar gels dissolved rapidly in the commonly used chromic acid cleaning solutions. Replicas were picked up on grids with thin Foimvar support films and stereo electron micrographs were obtained with a JEM-100 B electron microscope equipped with a 60° goniometer stage.Characteristic differences between gels of different concentrations (Figs. 1 and 2) were sufficiently pronounced to convince us that the structures observed are real and not the result of freezing artifacts.

A General Method for Spectrometer Design in the Scoff Approximation

1976 ◽  
Vol 34 ◽  
pp. 538-539
Author(s):  
J. R. Fields
Keyword(s):  
Electron Microscope ◽  
Transmission Electron Microscope ◽  
Energy Analysis ◽  
Incident Beam ◽  
Scanning Transmission Electron Microscope ◽  
Chemical Identification ◽  
Scanning Transmission Electron ◽  
Transmission Electron ◽  
Scanning Transmission ◽  
General Method

The energy analysis of electrons scattered by a specimen in a scanning transmission electron microscope can improve contrast as well as aid in chemical identification. In so far as energy analysis is useful, one would like to be able to design a spectrometer which is tailored to his particular needs. In our own case, we require a spectrometer which will accept a parallel incident beam and which will focus the electrons in both the median and perpendicular planes. In addition, since we intend to follow the spectrometer by a detector array rather than a single energy selecting slit, we need as great a dispersion as possible. Therefore, we would like to follow our spectrometer by a magnifying lens. Consequently, the line along which electrons of varying energy are dispersed must be normal to the direction of the central ray at the spectrometer exit.

Phase behavior of cationic and anionic surfactants at low concentrations

1992 ◽  
Vol 50 (1) ◽  
pp. 694-695
Author(s):  
E. Naranjo
Keyword(s):  
Phase Behavior ◽  
Structural Characterization ◽  
Dynamic Systems ◽  
Anionic Surfactants ◽  
Intermolecular Forces ◽  
Stable Form ◽  
Surfactant Mixtures ◽  
Low Concentrations ◽  
Cationic And Anionic Surfactants ◽  
General Method

Equilibrium vesicles, those which are the stable form of aggregation and form spontaneously on mixing surfactant with water, have never been demonstrated in single component bilayers and only rarely in lipid or surfactant mixtures. Designing a simple and general method for producing spontaneous and stable vesicles depends on a better understanding of the thermodynamics of aggregation, the interplay of intermolecular forces in surfactants, and an efficient way of doing structural characterization in dynamic systems.

Caricaturing as a general method to improve poor face recognition: Evidence from low-resolution images, other-race faces, and older adults.

2019 ◽  
Vol 25 (2) ◽  
pp. 256-279 ◽  
Author(s):  
Amy Dawel ◽  
Tsz Ying Wong ◽  
Jodie McMorrow ◽  
Callin Ivanovici ◽  
Xuming He ◽  
...  
Keyword(s):  
Older Adults ◽  
Face Recognition ◽  
Low Resolution ◽  
General Method ◽  
Low Resolution Images

Morphosemantic Analysis and Translation of Medical Compound Terms

1991 ◽  
Vol 30 (01) ◽  
pp. 30-35 ◽  
Author(s):  
P. Dujols ◽  
P. Aubas ◽  
C. Baylon ◽  
F. Grémy
Keyword(s):  
Medical Terms ◽  
General Method

This paper describes an automatic procedure for morphosemantic analysis and translation of compound medical terms. This analysis is of interest for the automatic indexation of medical discharge reports and summaries. Since words with the suffix -osis may have many different semantic interpretations, such -osis forms are taken as examples for a general method that avoids the difficulties in interpreting medical terms as reported in other studies.

Gold Catalyzed Hydroamination of Propargylic Alcohols: Controlling Divergent Reaction Pathways to Access 1,3-Aminoalcohols, 3-Hydroxyketones or 3-Aminoketones

2018 ◽  
Author(s):  
Victor Laserna ◽  
Tom Sheppard
Keyword(s):  
Gold Catalysis ◽  
Reaction Pathways ◽  
High Yield ◽  
Reaction Conditions ◽  
Propargylic Alcohols ◽  
Catalytic Quantity ◽  
Selective Formation ◽  
General Method

A versatile approach to the valorization of propargylic alcohols is reported, enabling controlled access to three different products from the same starting materials. Firstly, a general method for the hydroamination of propargylic alcohols with anilines is described using gold catalysis to give 3-hydroxy imines with complete regioselectivity. These 3-hydroxyimines can be reduced to give 1,3-aminoalcohols with high syn seletivity. Alternatively, by using a catalytic quantity of aniline, 3-hydroxyketones can be obtained in high yield directly from propargylic alcohols. Further manipulation of the reaction conditions enables the selective formation of 3-aminoketones via a rearrangement/hydroamination pathway.<br>

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