• Proceedings of the Korean Institute of Building Construction Conference
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• 2009.11a
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• pp.69-72
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• 2009

This research is focused on the applying of the foaming agent which can make the independent pore in the concrete structure in order to make a lightweight concrete structure. This lightweight foamed concrete can satisfy both the required strength and the mechanical properties as structural members. In addition, anti freezing-thawing properties also required. As a result of the unit volume-weight measurement, when the foaming agent mixed at 0.5% to 1%, the lightweight foamed concrete can be applied for the structural member. Also the density and compressive strength measurement results reveals that it will be suitable as structural member with 21MPa strength, when the density is betweenity8 to 1.9 and foaming agent quantities are 0.5% to 1%. Finally the result of freezing-thawing experiment, the effect freezing-thawing damage reduced according to adding foaming agent because those foaming agent make micro-pores in the structure which are not seen in the ordinary concrete structure.

• Journal of the Korea Institute of Building Construction
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• v.12 no.1
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• pp.22-30
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• 2012

Four types of foaming agents, including Alcohol Ethoxy Sulfate (AES), Alpha Olefin Sulfonate (AOS), Vegetable Soap (VS), and Fe-Protein (FP), are widely used in the construction field. These have different surface tensions and viscosities in water of the same concentration, affecting the flow speed of liquid, size and distribution of foam, and foam stability. However, there is a lack of data regarding the properties of foam concrete using various foam agents. The purpose of this study is to investigate influence of foaming agents on the properties of foamed concretes with various densities. We find that the foaming agent type has little effect on the density, compressive strength, and thermal conductivity of foam concrete, but considerably affects the unit weight of foam, flow and flexural strength of foamed concrete. While almost all properties of foam concrete are affected by density in fresh or hardened state, the potential energy changed by slurry density and the viscosity of foam are dominant factors in the flowability of foam slurry.

• Journal of the Korean Society of Food Science and Nutrition
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• v.22 no.6
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• pp.743-752
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• 1993

To elucidate the effects of natural gums, i.e. carrageenan, locust bean gum and xanthan gum and synthetic gums, i.e. carboxymethyl cellulose(CMC) and methyl cellulose(MC) on the foaming properties of sodium caseinate, surface tension, absolute viscosity, turbidity, foaming ability, foam stability, and heat stability of the foams of the caseinate solutions with added gums were examined. The surface tension of sodium caseinate solution(5%) adding to gums at pH 4.0 and 5.0 were higher than those at pH 7.0 and 8.0. The viscosities of the solutions adding to gums(0.1, 0.2, 0.3 and 0.5%) ap pH 4.0, 5.0, 7.0 and 8.0 were 2.4~170.0, 2.5~190.0, 5.3~180.0 and 6.3~99.0 cps, respectively. Especially xanthan gums predominantly increased the viscosity. Turbidities were 97.3~98.2 at pH 4.0 and 5.0 and 93.0~95.8 at pH 7.0 and 8.0. Foaming abilities of the solution adding to xanthan gum, carrageenan and locust bean gum were increased, while those of CMC and MC were decreased. Additions of xantham gum, CMC and MC increased the foam stability, especially xanthan gum did predominantly. Xanthan gum, MC and locust bean gum were more effective than CMC and carrageenan for heat stability. For improving the foaming properties of sodium caseinate xanthan gum were best of five kinds of gums. Surface tensions and turbidities of the solution were related to foaming ability, and the viscosities were related to foam stability and heat stability.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2011.05a
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• pp.123-125
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• 2011

Pre-foaming that has been used in this study is using to control and guarantee quality, but the optimum mix proportion and regulation are not definite. Therefore, this study investigated properties of foamed concrete according to concentrations of foaming agent to improve usability of foamed concrete. Synthetic foaming agent such as AES(Alkyl Ether Sulfate) and AOS(Alpha Olefin Sulfonate) are used to make foam with 1, 3, and 5% concentrations. We found that the flow of foam concrete increases when foam concentration is high and AES is more flowable than AOS. Density and compressive strength increase when foam concentration is low.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2019.11a
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• pp.77-78
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• 2019

Organic insulating materials can cause fatal toxic gases when burned, which can lead to human injury. As a combustible material, the risk of fire spreading is great. Therefore, there is a need for a study on the lightweight cured body for the non-combustible inorganic insulation to replace the flammable organic insulation. This study aims to examine the properties of lightweight foamed concrete according to the dilution concentration of animal foaming agent which forms a closed void when foaming as a part of the experiment to examine the utility of the lightweight foamed concrete as an insulating material. Bubbles occupy a large volume of lightweight foam concrete and have a great influence on the properties. Therefore, the stability of the bubble is very important, and as a result of the experiment, it is determined that 3% of the smallest vesicles are prepared at the proper dilution concentration.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2004.10a
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• pp.491-495
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• 2004

The industries use polymer materials for many purposes for they have many merits. The costs of these materials take up too great a proportion of the overall cost of products that use these materials as their major material. It is advantage for polymer industries to reduce these costs. The microcellular foaming process was developed in the early 1980s to solve this problem and proved to be quite successful. Microcellular foaming process uses inert gases such as $CO_2$, $N_2$. As these gases solve into polymer matrices, many properties are changed. The microcellular foaming process makes the glass transition temperature of polymers to low, and diminish the residual stress of polymer matrices. Besides, the microcellular foaming process has several merits, impact strength elevation, thermal insulation, noise insulation, and raw material saving etc. This characteristic of microcellular foaming process has influenced by cell morphology. The cell morphology means cell size and cell density. The cell morphology has influenced by many factors. The examples of factor are pressure drop rate, foaming temperature, foaming time, saturation pressure, saturation time etc. Among their factors, pressure drop rate is the most important factor for cell morphology in microcellular foaming injection molding process. This paper describes about the cell morphology change in accordance with the pressure drop rate of microcellular foaming injection molding process.

• Elastomers and Composites
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• v.58 no.2
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• pp.65-69
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• 2023

To reduce the weight of the engineering plastic Nylon 6 resin, two high-temperature foaming agents, p-toluenesulfonyl semicarbazide (PTSS) and 5-phenyltetrazole (5-PT) (0-10 phr), were added and foamed without other additives. We investigated the effects of the foaming agent type and content on the foam density (g/cm³) and percent weight reduction rate of the Nylon 6 foam, and 5-PT exhibited better foaming performance than PTSS. In the case of 5-PT, the weight reduction rate was above 36% when the blowing agent content was 1.5 phr or higher, indicating that 5-PT is an effective blowing agent for reducing the Nylon 6 foam weight. Additionally, we studied the effect of the nucleating agent Talc content (0-0.4 phr) on Nylon 6 foaming, and the nucleating agent Talc considerably reduced foaming.

• Korean Journal of Food Science and Technology
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• v.36 no.5
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• pp.728-732
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• 2004

Convenient method for determination of egg white foaming properties was suggested. Highly reproducible results were obtained when 70g egg white was whipped at 1,200 rpm for 2 min. Using standardized testing method, foaming capacity and stability of egg white samples including fresh egg white, freeze-dried egg white and commercial egg white powder were effectively differentiated. Foaming capacity of egg white was not affected during storage of fresh egg white up to 4 weeks at $4^{\circ}C$, whereas foaming stability significantly decreased after 2 weeks of storage.

• Korean Journal of Materials Research
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• v.21 no.6
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• pp.314-319
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• 2011

Melt foaming method is one of cost-effective methods to make metal foam and it has been successfully applied to fabricate Mg foams. In this research, AZ31 Mg alloy ingot was used as a metal matrix, using AlCa granular as thickening agent and $CaCO_3$ powder as foaming agent, AZ31 Mg alloy foams were fabricated by melt-foaming method at different foaming temperatures. The porosity was above 41.2%~73.3%, pore size was between 0.38~1.52 mm, and homogenous pore structures were obtained. Microstructure and mechanical properties of the AZ31 Mg alloy foams were investigated by optical microscopy, SEM and UTM. The results showed that pore structure and pore distribution were much better than those fabricated at lower temperatures. The compression behavior of the AZ31 Mg alloy foam behaved as typical porous materials. As the foaming temperature increased from $660^{\circ}C$ to $750^{\circ}C$, the compressed strength also increased. The AZ31 Mg alloy foam with a foaming temperature of $720^{\circ}C$ had the best energy absorption. The energy absorption value of Mg foam was 15.52 $MJ/m^3$ at a densification strain of 52%. Furthermore, the high energy absorption efficiencies of the AZ31 Mg alloy foam kept at about 0.85 in the plastic plateau region, which indicates that composite foam possess a high energy absorption characteristic, and the Vickers hardness of AZ31 Mg alloy foam decreased as the foaming temperature increased.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.25 no.4
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• pp.637-644
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• 2001

Polymer materials have a lot of merits including the low cost and the easiness of forming. For these reasons they are widely using at many manufacturing industries. Microcellular foaming process appeared at MIT in 1980s to save a quantity of material and increase mechanical properties. There are many process variables in appling microcellular foaming process to the conventional injection molding process. They can be solved by using Axiomatic Design Method which is very useful design method for designing a new product. Its main character is scientific and analytical. The information about the thickness of cavity plays an important role in making an effective foam. The goal of this research is to design mold system for advance of foaming magnitude with axiomatic design method. There is a relation between the change of cavitys thickness and foaming magnitude made after inserting a gas. R/t is a conception that indicate proportion between radius and thickness of cavity in mold system. By means of SEM observation of side surface of cavity sample, foaming magnitude of polymer in microcellular foaming process is decreasing gradually as the value of R/t is increasing. In this paper, an advanced mold system was presented by mapping the relation between functional requirements and design parameters.