The weight-effectiveness index of two-component materials used for shielding against neutrons and ?-rays

For this study, three-dimensional models of the soles of work shoes of different thicknesses and consisting of different materials were created. These models were analyzed to obtain the distribution of stress and strain on their surfaces. To build the model, we used experimental data on the shape and size of the sole, as well as the properties of specific materials used in the manufacture of soles for work shoes used in agriculture. The goal was to determine the most suitable material, that is, which of the materials has the most suitable characteristics for the sole, has the best wear resistance when used in agriculture. We noticed a significant reduction in deformations on the surface of the sole with an increase in the thickness of the sole, as well as when using two-component casting of the sole from a combination of materials: low-density EVA and flexible PU, medium-density EVA and soft PVC. This indicates their advantages and maximum suitability.

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An Experimental Study to Evaluate the Performance of Competing Filler Materials Used With Type B and Stand-Off Steel Sleeves

Volume 3: Operations, Monitoring and Maintenance; Materials and Joining ◽

10.1115/ipc2016-64104 ◽

2016 ◽

Author(s):

Chris Alexander ◽

Alan Beckett

Keyword(s):

Experimental Study ◽

Filler Material ◽

Filler Materials ◽

Type B ◽

Systematic Method ◽

Two Component ◽

Concentration Factors ◽

Materials Used ◽

Stress Concentration Factors ◽

Steel Sleeve

An experimental study was conducted to evaluate the performance of various filler materials used in Type B tight-fit and stand-off steel sleeve designs. Full-scale testing was performed to examine the performance of three filler materials and two sleeve types reinforcing four separate dents subjected to cyclic internal pressure. All filler materials were installed with the test pipe at 55°F and allowed to cure for 7 days. The metric for comparing filler material performance was stress concentration factors (SCFs) measured in the dents in the unrepaired and repaired configurations. The filler materials included a two-component epoxy, an epoxy-based grout, and a cement-based grout. The average SCF for the unreinforced dents was 5.64, while after reinforcement the average SCF was 1.2 (an average reduction of 79%). The results of this study generated two important findings. First, the stand-off sleeve design was able to provide reinforcement similar to what was measured for the tight-fit sleeve. Second, the study determined that the cement-based grout actually slightly outperformed the epoxy-based grout, the latter being the filler material of choice prior to this study. This paper provides readers with practical information and data on the performance of competing filler material types, while also presenting a systematic method for evaluating different methods of reinforcement.

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Spectroscopic Observations of Visual Double Stars

International Astronomical Union Colloquium ◽

10.1017/s0252921100027536 ◽

1965 ◽

Vol 5 ◽

pp. 109-111

Author(s):

Frederick R. West

Keyword(s):

Radial Velocity ◽

High Dispersion ◽

Velocity Difference ◽

Spectrograph Slit ◽

Spectroscopic Observations ◽

Double Stars ◽

Visual Double Stars ◽

Relative Orbit ◽

Two Component ◽

Star Images

There are certain visual double stars which, when close to a node of their relative orbit, should have enough radial velocity difference (10-20 km/s) that the spectra of the two component stars will appear resolved on high-dispersion spectrograms (5 Å/mm or less) obtainable by use of modern coudé and solar spectrographs on bright stars. Both star images are then recorded simultaneously on the spectrograph slit, so that two stellar components will appear on each spectrogram.

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Deformation Replication

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100068394 ◽

1970 ◽

Vol 28 ◽

pp. 280-281

Author(s):

J. Temple Black

Keyword(s):

Cutting Speed ◽

Machining Process ◽

Depth Of Cut ◽

Rake Face ◽

Orthogonal Machining ◽

Aluminum Chips ◽

Before And After ◽

Materials Used ◽

Glass Knife ◽

Very High

Tool materials used in ultramicrotomy are glass, developed by Latta and Hartmann (1) and diamond, introduced by Fernandez-Moran (2). While diamonds produce more good sections per knife edge than glass, they are expensive; require careful mounting and handling; and are time consuming to clean before and after usage, purchase from vendors (3-6 months waiting time), and regrind. Glass offers an easily accessible, inexpensive material ($0.04 per knife) with very high compressive strength (3) that can be employed in microtomy of metals (4) as well as biological materials. When the orthogonal machining process is being studied, glass offers additional advantages. Sections of metal or plastic can be dried down on the rake face, coated with Au-Pd, and examined directly in the SEM with no additional handling (5). Figure 1 shows aluminum chips microtomed with a 75° glass knife at a cutting speed of 1 mm/sec with a depth of cut of 1000 Å lying on the rake face of the knife.

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High Voltage Transmission Microscopy of Surveyor III Camera Shrouds

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100064748 ◽

1971 ◽

Vol 29 ◽

pp. 138-139

Author(s):

W. R. Duff ◽

L. E. Thomas ◽

R. M. Fisher ◽

S. V. Radcliffe

Keyword(s):

Alloy Sheet ◽

Transmission Microscopy ◽

Television Camera ◽

Window Method ◽

Transmission Electron ◽

Microstructural Effects ◽

Lunar Environment ◽

Successful Retrieval ◽

Materials Used ◽

Abrasive Paper

Successful retrieval of the television camera and other components from the Surveyor III spacecraft by the Apollo 12 astronauts has provided a unique opportunity to study the effects of a known and relatively extensive exposure to the lunar environment. Microstructural effects including those produced by micro-meteorite impact, radiation damage (by both the solar wind and cosmic rays) and solar heating might be expected in the materials used to fabricate the spacecraft. Samples received were in the form of 1 cm2 of painted unpainted aluminum alloy sheet from the top of the camera visor (JPL Code 933) and the sides (935,936) and bottom (934) of the lower camera shroud. They were prepared for transmission electron microscopy by first hand-grinding with abrasive paper to a thickness of 0.006". The edges were lacquered and the sample electropolished in 10% perchloric methanol using the “window” method, to a thickness of ~0.001". Final thinning was accomplished by polishing 3 mm punched disks in an acetic-phosphoric-nitric acid solution.

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Structure-property relationships of PE/PP sandwiched films

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100126998 ◽

1987 ◽

Vol 45 ◽

pp. 454-455

Author(s):

J. Petermann ◽

G. Broza ◽

U. Rieck ◽

A. Jaballah ◽

A. Kawaguchi

Keyword(s):

Mechanical Tests ◽

Polymer Materials ◽

Ionic Crystals ◽

Structure Property ◽

Polymer Systems ◽

Structure Property Relationships ◽

Oriented Films ◽

Materials Used ◽

Polymer Laminates ◽

Heated Glass

Oriented overgrowth of polymer materials onto ionic crystals is well known and recently it was demonstrated that this epitaxial crystallisation can also occur in polymer/polymer systems, under certain conditions. The morphologies and the resulting physical properties of such systems will be presented, especially the influence of epitaxial interfaces on the adhesion of polymer laminates and the mechanical properties of epitaxially crystallized sandwiched layers.Materials used were polyethylene, PE, Lupolen 6021 DX (HDPE) and 1810 D (LDPE) from BASF AG; polypropylene, PP, (PPN) provided by Höchst AG and polybutene-1, PB-1, Vestolen BT from Chemische Werke Hüls. Thin oriented films were prepared according to the method of Petermann and Gohil, by winding up two different polymer films from two separately heated glass-plates simultaneously with the help of a motor driven cylinder. One double layer was used for TEM investigations, while about 1000 sandwiched layers were taken for mechanical tests.

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A technique for protecting delicate specimens during processing

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100156894 ◽

1989 ◽

Vol 47 ◽

pp. 982-983

Author(s):

R.J. Mount ◽

R.V. Harrison

Keyword(s):

Basilar Membrane ◽

Low Cost ◽

Organ Of Corti ◽

Region Of Interest ◽

Sensory Epithelium ◽

Physical Damage ◽

Air Drying ◽

Specimen Handling ◽

Two Component

The sensory end organ of the ear, the organ of Corti, rests on a thin basilar membrane which lies between the bone of the central modiolus and the bony wall of the cochlea. In vivo, the organ of Corti is protected by the bony wall which totally surrounds it. In order to examine the sensory epithelium by scanning electron microscopy it is necessary to dissect away the protective bone and expose the region of interest (Fig. 1). This leaves the fragile organ of Corti susceptible to physical damage during subsequent handling. In our laboratory cochlear specimens, after dissection, are routinely prepared by the O-T- O-T-O technique, critical point dried and then lightly sputter coated with gold. This processing involves considerable specimen handling including several hours on a rotator during which the organ of Corti is at risk of being physically damaged. The following procedure uses low cost, readily available materials to hold the specimen during processing ,preventing physical damage while allowing an unhindered exchange of fluids.Following fixation, the cochlea is dehydrated to 70% ethanol then dissected under ethanol to prevent air drying. The holder is prepared by punching a hole in the flexible snap cap of a Wheaton vial with a paper hole punch. A small amount of two component epoxy putty is well mixed then pushed through the hole in the cap. The putty on the inner cap is formed into a “cup” to hold the specimen (Fig. 2), the putty on the outside is smoothed into a “button” to give good attachment even when the cap is flexed during handling (Fig. 3). The cap is submerged in the 70% ethanol, the bone at the base of the cochlea is seated into the cup and the sides of the cup squeezed with forceps to grip it (Fig.4). Several types of epoxy putty have been tried, most are either soluble in ethanol to some degree or do not set in ethanol. The only putty we find successful is “DUROtm MASTERMENDtm Epoxy Extra Strength Ribbon” (Loctite Corp., Cleveland, Ohio), this is a blue and yellow ribbon which is kneaded to form a green putty, it is available at many hardware stores.

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