The stress distribution in spherical shells with a cylindrical branch pipe

1971 ◽  
Vol 7 (9) ◽  
pp. 964-968
Author(s):  
I. S. Chernyshenko
Keyword(s):  
Stress Distribution ◽  
Branch Pipe ◽  
Spherical Shells ◽  
Cylindrical Branch

Penetrations in Shells Under External Pressure

1970 ◽  
Vol 92 (2) ◽  
pp. 269-274
Author(s):  
R. C. DeHart ◽  
L. F. Greimann
Keyword(s):  
Finite Element ◽  
Stress Distribution ◽  
Stress Condition ◽  
External Pressure ◽  
Experimental Stress ◽  
Spherical Shells ◽  
Premature Failure ◽  
Resistant Structure ◽  
Theoretical Results ◽  
Stress Analyses

Penetrations, in the pressure-resistant structure of a submersible, disturb the stress condition in the shell and may cause a premature failure. In this paper, two types of finite-element solutions are used to predict the stress distribution near view port openings in spherical shells under external pressure. Results of experimental stress analyses are also given and compared to the theoretical results.

scholarly journals THEORETICAL STUDY OF THE PROCESS OF MIXING THE VARIOUS COMPONENTS IN THE WORKING CHAMBER OF THE DISINTEGRATOR

2019 ◽  
Vol 4 (7) ◽  
pp. 102-107
Author(s):  
И.А. Семикопенко ◽  
I.A. Semikopenko ◽  
В. Воронов ◽  
Vitaliy Voronov ◽  
Д. Беляев ◽  
...  
Keyword(s):  
Theoretical Study ◽  
Functional Dependence ◽  
Branch Pipe ◽  
The Body ◽  
Initial Value ◽  
Working Chamber ◽  
Mixing Chamber ◽  
Cylindrical Branch ◽  
Component Loading ◽  
Row Space

This article analyzes the movement of particles of different components in the inter-row space and in the peripheral part of the disintegrator's working chamber. The diagram of the disintegrator with the component loading unit and the diagram of the disintegrator's working chamber are presented. The loading unit consists of two screw feeders, which supply various components to the conical loading hopper. The capacity of the screw feeders is matched with the capacity of the hopper and the vertical cylindrical branch pipe. The mass capacity of the mixing chamber and the grinding of the disintegrator is determined. Mass throughput is determined using the functional dependence of the change in the bulk density of the material during its passage in the radial direction from the radius of scattering disk Rд to the radial size of the disintegrator body. It is determined that the mass throughput depends on the geometric (Rk, Rg, H) and technological (ϑ_r ) parameters of the disintegrator. The movement of the material in the working chamber of the disintegrator and the change in the concentration of the selected components of the mixture are presented on the basis of the cell mixing model. It allows to determine the concentration of the selected component of the mixture at the outlet of the body of the disintegrator in the tangential discharge pipe. According to expression, the concentration of the selected components of the mixture when passing through the disintegrator body of the presented construction is about half (0.57) of the initial value.

The concerted use of SEM, TEM, and SCM for examination of resin-dentin interfaces

1994 ◽  
Vol 52 ◽  
pp. 476-477
Author(s):  
B. Van Meerbeek ◽  
L. J. Conn ◽  
E. S. Duke
Keyword(s):  
Surface Layer ◽  
Stress Distribution ◽  
Phosphoric Acid ◽  
Bonding Mechanism ◽  
Restorative Dentistry ◽  
Dental Adhesive ◽  
Low Viscosity ◽  
Dentin Adhesives ◽  
Acid Etch ◽  
Tooth Tissue

Restoration of decayed teeth with tooth-colored materials that can be bonded to tooth tissue has been a highly desirable property in restorative dentistry for many years. Advantages of such an adhesive restorative technique over conventional techniques using non-adhesive metal-based restoratives include improved restoration retention with minimal sacrifice of sound tooth tissue for retention purposes, superior adaptation and sealing of the restoration margins in prevention of caries recurrence, improved stress distribution across the tooth-restoration interface throughout the whole tooth, and even reinforcement of weakened tooth structures. The dental adhesive technology is rapidly changing. An efficient resin bond to enamel has already long been achieved. Its bonding mechanism has been fully elucidated and has proven to be a durable and reliable clinical treatment. However, bonding to dentin represents a greater challenge. After the failures of a dentin acid-etch technique in imitation of the enamel phosphoric-acid-etch technique and a bonding procedure based on chemical adhesion, modern dentin adhesives are currently believed to bond to dentin by a micromechanical hybridization process. This process is developed by an initial demineralization of the dentin surface layer with acid etchants exposing a collagen fibril arrangement with interfibrillar microporosities that subsequently become impregnated by low-viscosity monomers. Although the development of such a hybridization process has well been documented in the literature, questions remain with respect to parameters of-primary importance to adhesive efficacy.

Sign in / Sign up

Export Citation Format

Share Document