• Progress in Medical Physics
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• v.32 no.4
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• pp.159-164
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• 2021

Purpose: We investigated the properties of CLEANBOLUS based on silicone with suitable characteristics for clinical use. Methods: We evaluated the characteristics of CLEANBOLUS and compared the results with the commercial product (Super-Flex bolus). Also, we conducted physical evaluations, including shore hardness, element composition, and elongation break. Transparency was investigated through the measured absorbance within the visible region (400-700 nm). Also, dosimetric characteristics were investigated with surface dose and beam quality. Finally, the volume of unwanted air gap was investigated based on computed tomography images for breast, chin, and nose using Super-Flex bolus and CELANBOLUS. Results: CLEANBOLUS showed excellent physical properties for a low shore hardness (000-35) and elongation break (>1,000%). Additionally, it was shown that CLEANBOLUS is more transparent than Super-Flex bolus. Dosimetric results obtained through measurement and calculation have an electron density similar to water in CLEANBOLUS. Finally, CLEANBOLUS showed that the volume of unwanted air gap between the phantom and each bolus is smaller than Super-Flex bolus for breast, chin, and nose. Conclusions: The physical properties of CLEANBOLUS, including excellent adhesive strength and lower shore hardness, reduce unwanted air gaps and ensure accurate dose distribution. Therefore, it would be an alternative to other boluses, thus improving clinical use efficiency.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2013.11a
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• pp.173-174
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• 2013

In this study, the tensile properties of sealants by heat deterioration were measured and analysed to gather the basic data of sealant because these studies do not have been investigated in Korea. Most general one-component silicone sealants were used and test specimen was I-type. The test parameters are sealant types which have different density and heat deterioration time in 80℃. As a result, the rat of reduction in area by heat deterioration was considerable increased at SR-A compared with SR-B. The tensile properties by heat deterioration decreased at SR-A because the specimen by deterioration occurred adhesive failure before tensile test. However, SR-B specimen was increased at maximum tensile stress but decreased at elongation in maximum tensile stress. Also, Maximum principal stress was measured at the edge of specimen by FEM simulation in order to find out failure points.

• Journal of the Korean Society of Safety
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• v.16 no.1
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• pp.43-47
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• 2001

Effect of coupling agent on the mechanical properties of PP/GF blend was investigated. The flexural modulus, Izod impact strength, elongation at yield and tensile strength were improved with using coupling agent. Mopological studies revealed that PP and GF were incompatible and addition of coupling agent was very effective to enhance the compatibility, result in mechanical properties.

• Journal of the Korean Society for Precision Engineering
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• v.6 no.4
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• pp.103-107
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• 1989

The effects of annealing temperature on the magnetic properties (maximum permeability, coercive force and remanence) and mechanical properties (hardness, tensile strength and elongation at rupture) were analyzed using the nondestructive impulsive magnetic analyzer in a medium carbon cold rolled steel sheet. This nondestructive method was very useful for the analysis of magnetic and mechanical properties of materials. As it was known in the literature, the three distinct processes that indicate the recovery, recrystallization, and grain growth of a metal were measured with the non-destructive analyzer.

• Proceedings of the Korea Concrete Institute Conference
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• 1997.10a
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• pp.659-664
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• 1997

RC structures can deteriorate for many defective factors. In the repair and retrofit works of concrete, epoxy resins are widely used as repair materials. The object of this study is to investigate the material properties and durabilities of epoxy resins which are commonly used in repairing concrete. The material properties such as line-expansion modulus, viscosity, microstructure and physical parameter as well as the durabilities such as gravity change, tensile strength, elongation change were carried out.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 1999.11a
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• pp.498-500
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• 1999

Polyacetals with melamine were investigated in terms of mechanical properties. It was found that tensile strength, impact strength and elongation were decreased with the increase of melamine content up to 30 par, flexural strength had no remarkable changes. For master-batch using polyurethane as carrier resin, in which the ratio of polyurethane to melamine was 2:1, tensile strength and flexural strength were decreased and impact strength remained unchanged with melamine me content.

• Transactions of Materials Processing
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• v.13 no.5
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• pp.449-454
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• 2004

The annealing behavior of a 5083 Al alloy deformed at cryogenic temperature was investigated, focusing on the evolution of microstructures and mechanical properties. Especially, the effects of annealing temperature, $150~300^{\circ}C$, and time, 3∼60min., on microstructures and mechanical properties of the sheets received 85% reduction at cryogenic temperature were investigated. The optimization of the annealing conditions resulted in a mixture of equiaxed grains and elongated subgrains, exhibiting a good combination of uniform elongation and high strength.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.35 no.4
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• pp.417-423
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• 2002

The edible films were prepared from the protein of alaska pollack, Theragra chalcogrmma. Effects of plasticizer, cross linker and laminated film on physical properties such as tensile strength (TS), elongation (E) and water vapor permeability (WVP) of films were investigated. In adding various kinds of plasticizers, TS of the films prepared with propylene glycol (PG) was the highest, and followed sorbitol, polyethylene glycol 200 (PEG 200) and glycerol. Elongation of the films prepared with glycerol was the highest, then sorbitol, PEG 200 and PG. WVP of films showed lower in order of PG, sorbitol, glycerol and PEG 200.75 decreased with the increment of plasticizer concentration, but elongation increased, The addition of both PG and PEG 200 effected weakly on elongation, so they were inadequate as plasticizer for the film. Mixtures of glycerol and sorbitol, which showed opposing both TS and elongation in the films, could control the physical properties of the films. With increasing relative humidity, TS decreased, while elongation and equilibrium moisture content increased. By adding the cross linkers such as ascorbic acid, citric acid and succinic acid, TS and m of films increased, while elongation decreased. Ascorbic acid, citric acid, succinic acid were most effective for TS at 0.2, 0.1 and $0.1\%, respectively. Laminated film with alaska pollack protein and corn zein improved TS above two times, reduced WVP about $20\~30\%$, as compared with the Elm from alaska pollack protein. Two films did not show the difference to oxygen permeability, but they showed about tenfold greater oxygen resistance than polyethylene film. Laminated film showed higher b and $\Delta$E value of color difference, lower a and L value than the film from alaska pollack protein.

• Journal of the Korean Society for Heat Treatment
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• v.10 no.1
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• pp.1-9
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• 1997

The variation of the mechanical properties and the formation of retained austenite with heat treatment conditions in austempered Si bearing carbon steels has been investigated. In the case of a steel containing 0.35C-1.48Si-0.95Mn, it has been found that a feather shape bainite structure of lath are obtained under a isothermal treated condition at just below the Ms temperature, and the martensite, bainitic ferrite and retained austenite of second phase particles on the ferrite matrix for a isothermal treated steels after intercritical annealing are precipitated in a linked shape. The retained austenite with $2{\mu}m$ size induced as TRIP is found to increase with increasing the formation rate of retained austenite for the intercritical annealing and high Si containing steels. The tensile strength is increased as austempering temperature increases in all isothermal treatment temperature, whereas the elongation is shown to roughly decrease as the tensile strength increases. The values of tensile strength-elongation balance have showed a marked dependence upon the elongation rather than the tensile stregth, and their values are increased for high Si containing steels and intercritical annealing condition. The most optimum result has been shown to be the tensile stregth-elongation balance of $2882.4kgf/mm^2.%$ and the elongation of 33.3% for a "B" steel in the heat treating temperature range of $780{\sim}370^{\circ}C$.

• Korea-Australia Rheology Journal
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• v.17 no.1
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• pp.1-7
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• 2005

Acrylonitrile-Butadiene-Styrene (ABS), polycarbonate (PC) and their alloys are an important class of engineering thermoplastics that are widely used for automotive industry, computer and equipment housings. For the process of recycling mixtures of ABS and PC, it is desirable to know how sensitive the blend properties are to changes in compositions. It was for this reason that blends of virgin ABS and virgin PC at five different compositions, namely, $15\%,\;30\%,\;50\%,\;70%$ and $85\%$ by weight of ABS were prepared and characterised by rheological and mechanical measurements. Rheological properties of these blends in steady, oscillatory and transient step shear and mechanical properties, namely, tensile strength, elongation-at-break and Izod impact strength are reported. The results show that PC behaves in a relatively Newtonian manner, but ABS exhibits significant shear thinning. The ABS-rich blends show a trend that is similar to that of ABS, while PC-rich blends, namely $0\%$ and $15\%$, exhibit a nearly Newtonian behaviour. However, at a fixed shear rate or frequency, the steady shear or the dynamic viscosity varied respectively in a non-mono-tonic manner with composition. Except for $15\%$ blend, the viscosities of other blends fall into a narrow band indicating a wide-operation window of varying blend ratio. The blends exhibited a lower viscosity than either of the two pure components. The other noticeable feature was that the blends at $70\%$ and $85\%$ ABS content had a higher G' than pure ABS, indicating an enhancement of elastic effect. The tensile yield strength of the blends followed the 'rule of mixtures' showing a decreasing value with the increase of ABS content in PC. However, the elongation-at-break and the impact strength did not appear to obey this 'rule of mixtures,' which suggests that morphology of the blends also plays a significant role in determining the properties. Indeed, scanning electron micrographs of the fracture surfaces of the different blends validate this hypothesis, and the $15\%$ blend is seen to have the most distinct morphology and correspondingly different behaviour and properties.