• Korean Journal of Poultry Science
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• v.15 no.1
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• pp.39-44
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• 1988

This study was undertaken to find out the effect of heating time and temperature, pH and NaCl concentration on heat sensitivity of egg albumen during heat treatment. Sharp increase of the turbidity and rapid decrease of the foaming power were observed when egg albumen was heated at above $60^{\circ}C$. Egg albumen became opaque when it was heated at $60^{\circ}C$ for above 13 minutes or at $65^{\circ}C$ for above 5 minutes. The turbidity was markedly increased at below pH 7 and the foaming power was largely decreased at around pH 4.0 by the heat treatment ($60^{\circ}C$, 5 min). The foam stability was slightly decreased at alkaline pH range by the heat treatment (60t, 5 min). The addition of NaCl up to 0.3M decreased the turbidity. There was no effect of NaCl addition on the foaming power, but the foam stability was decreased by the addition of NaCl at above 0.2M before and after the heat treatment ($60^{\circ}C$, 5 min).

• Polymer(Korea)
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• v.36 no.1
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• pp.34-40
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• 2012

The foaming of poly(butylene succinate) (PBS) using supercritical $CO_2(scCO_2)$ was studied. In order to improve the melt strength, PBS was modified using the reactive compounding technique. Rapid decompression of $scCO_2$-saturated PBS at a temperature above the depressed $T_m$ yielded expanded microcellular foams. The resulting foam structure could be controlled by manipulating process conditions. Experiments varying the foaming temperature while holding other variables constant showed that higher temperatures produced larger cells and reduced cell densities. Higher saturated pressures led to higher nucleation densities and smaller cell sizes. Decreasing the rate of depressurization permitted a longer period of cell growth and therefore larger cells were obtained.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.6 no.1
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• pp.94-103
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• 2005

The low foamed high strengthen styrofoam samples made by dielectric heating are discussed. We used the oscillator which have the frequency of 13.6 MHz and the power of 7 kW. 3 times expanded beads by steaming method were used in our foam-molding test. Internal fusion properties and density of internal structure were improved by dielectric foaming process. At the temperature of $105-110^{\circ}C$, the internal fusion property was maximally improved.

• Transactions of Materials Processing
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• v.12 no.5
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• pp.457-464
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• 2003

In the powder compact melting technique, proper precursor fabrication is very important because density distribution after foaming and foamability are determined during precursor fabrication process. The fabrication of the precursor has to be performed very carefully because any residual porosity or other defects will lead to poor results in further processing. In order to evaluate the effect of the compaction parameters on the kinetics of the foaming process, a series of experiments were performed. In this study, aluminium foams with a closed cell structure were fabricated by using both the powder compact method and the induction heating process. A proper induction coil was designed to obtain a uniform temperature distribution over the entire cross sectional area of precursor. To establish the foamable precursor fabrication conditions, effects of process parameters such as the titanium hydride content (0.3∼1.5 wt.%), pressing pressure of the foamable precursor (50∼150kN) on the pore morphology were investigated.

• Proceedings of the IEEK Conference
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• 2001.10a
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• pp.427-431
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• 2001

In this research, porous materials were made from mine's waste slime. As a temperature changes, a phase changes, a porosity, and a mechanical strength of porous materials were observed and measured. The process of pore-formation was observed by SEM according to the change of heat-treatment temperature and time. It fumed out that the foaming reaction of mine's waste slime was resulted from liquid phase by decomposition of the sanidine and the muscovite-3T. When heat- treated at over 120$0^{\circ}C$, it appeared high porosity. And, to activate the foaming reaction, an alkaline oxide concerned with liquid formation was added and its effects were examined.

• Journal of Korea Foundry Society
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• v.31 no.3
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• pp.145-151
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• 2011

Metallic foam has been known as a functional material which can be used for absorption properties of energy and sound. The unique characteristics of Al foam of mechanical, acoustic, thermal properties depend on density, cell size distribution and cell size, and these characteristics expected to apply industry field. Al-Zn-Mg-Cu alloy foams was fabricated by following process; firstly melting the Al alloy, thickening process of addition of Ca granule to increased of viscosity, foaming process of addition of titanium hydride powder to make the pores, holding in the furnace to form of cooling down to the room temperature. Metal foams with various porosity level were manufactured by change the foaming temperature. Compressive strength of the Al alloy foams was 2 times higher at 88% porosity and 1.2 times higher at 92% porosity than pure Al foams. It's sound and vibration absorption coefficient were higher than pure Al foams and with increasing porosity.

• Korean Journal of Materials Research
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• v.12 no.9
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• pp.729-734
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• 2002

Porous Al metal was produced by batch type casting process. In this foaming process, the viscosity and surface tension of molten Al as two most important factors have been investigated in the temperature range of 680-95$0^{\circ}C$ by the ring method and rotational method respectively. The experimental results showed that both the surface tension and viscosity of the melt decreased linearly with increasing temperature. Addition of Ca decreased surface tension, but increased viscosity significantly.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2018.05a
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• pp.58-59
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• 2018

In this study, firing experiments were carried out to confirm the foamability of the expansive shale collected from the local area. When expansive shales are subjected to high temperature heat, gas is generated inside and voids are formed. Due to this phenomenon, shale is used as a raw material for lightweight aggregate. Experiments were carried out with different plastic temperature and residence time to find the appropriate plastic temperature for this expansive shale. As a result, the higher the plastic temperature, the more the surface viscosity increased and the gas generated inside were retained. Resulting in a number of internal voids. However, even if the plastic temperature or the medium temperature is high, it is confirmed that sufficient gas is not generated when the residence time is shortened.

• Korean Journal of Food Science and Technology
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• v.31 no.3
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• pp.658-664
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• 1999

Broiler and porcine blood plasma were desugarized by GOD (glucose oxidase 10 units/g) or baker's yeast (0.3% w/w) and dried. The color, biuret protein content, solubility, foaming capacity and pH of desugarized blood plasma powder during storage at room temperature were investigated. Desugarized plasma powder was lighter and less red and yellow than the control group (P<0.05). Biuret protein content and solubility of deglucosed plasma powder were higher than the control. Biuret protein content and solubility of all samples decreased during storage (P<0.05). Generally, deglucosed samples showed better foaming capacity than the controls (P<0.05). The pH of deglucosed broiler samples by yeast and porcine samples were decreased just after initial increasing, while the pH of other broiler powder was continuously decreased during storage. Deglucosed porcine powder always showed higher pH values than the control (P<0.05). Overall, desugatization of broiler or porcine blood plasma before drying improved color, biuet protein content, solubility and foaming capacity.

• Polymer(Korea)
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• v.37 no.4
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• pp.494-499
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• 2013

Modified polypropylene (m-PP) was fabricated by furfuryl sulphide (FS) as branching agent and m-PP/nano-filler composites were prepared with silicate and multi-walled carbon nanotube (MWCNT), using a twin screw extruder. The chemical structures and thermal properties of the m-PP were investigated by FTIR and DSC. The chemical structure of the m-PP was confirmed by the existence of =C-H stretching peak of the branching agent at 3100 $cm^{-1}$. There was no district change in melting temperature in case of m-PP, but a certain increase in crystallization temperature was notified and the increase was in the range of $10-20^{\circ}C$. The rheological properties, filler dispersion and foaming behaviors of the m-PP/nano-filler composites were investigated by dynamic rheometer, X-ray diffractometer (XRD) and scanning/transmission electron microscope (SEM/TEM). m-PP/nano-filler composites showed a high complex viscosity at a low frequency, an increase in melt elasticity, and a high shear thinning effect. Compared to pure PP, m-PP and m-PP/nano-filler composites were sufficient to enhance the foaming behavior.