• Journal of Powder Materials
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• v.22 no.2
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• pp.87-92
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• 2015

Metallic porous materials have many interesting combinations of physical and geometrical properties with very low specific weight or high gas permeability. In this study, highly porous Cu foam is successfully fabricated by a slurry coating process. The Cu foam is fabricated specifically by changing the coating amount and the type of polyurethane foam used as a template. The processing parameters and pore characteristics are observed to identify the key parameters of the slurry coating process and the optimized morphological properties of the Cu foam. The pore characteristics of Cu foam are investigated by scanning electron micrographs and micro-CT analyzer, and air permeability of the Cu foam is measured by capillary flow porometer. We confirmed that the characteristics of Cu foam can be easily controlled in the slurry coating process by changing the microstructure, porosity, pore size, strut thickness, and the cell size. It can be considered that the fabricated Cu foams show tremendous promise for industrial application.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.24 no.12
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• pp.3018-3025
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• 2000

It is possible to shorten developing process by making model using polyurethane foam in the area of automobile development process, etc. However, this skill is too difficult to be of practical use because machining is not easy due to characteristic of polyurethane foam. Domestic and foreign automobile company use clay, polyurethane foam. etc,, those are easy to handle and to make model after completing design sketch. But these materials is difficult to the machined and be worked by humans hand, There are so many difficult problem for machining by making model using polyurethane foam since cutting of elastic body like polyurethan foam has never been studied. Therefore, in this study, it is investigated to measured cutting force that is generated in case of polyurethane foam machining, and to make systematize tool compensation of polyurethane foam cutting work on automobile model by modification of tool offset method on existing steel.

• Journal of Life Science
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• v.8 no.5
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• pp.504-508
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• 1998

A study was conducted to evaluate a protein removal characteristics by foam separation. The foam separator was operated in well-mixed tank which would be considered as a completely mixed condition. The feasibility of foam separation to remove protein from fresh and sea water was investigated. Protein removal characteristics of the foam separator were obtained by batch reactor operations. To find the effect of the operating parameter to protein removal rate, the foam separation was carried with variation of initial protein concentration and foam height. The results indicated that the protein removal efficiency was increased with increasing protein concentration and decreased with increasing foam height. The relationship between protein concentration and protein removal rate was evaluated by linear regression.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.37 no.6
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• pp.498-504
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• 2004

Removal of waste generated by Paralichthys olivaceus in the seawater aquarium using a foam separator was investigated. Protein concentration without a foam separator continuously increased until 3 days after stocking and reached at 25 mg/L after 5 days stocking, but protein concentration became lower than the initial protein concentration (2.5 mg/L) with a foam separator. The trends of other fish wastes such as ammonia, total suspended solids (TSS) and chemical oxygen demand (COD) were similar to protein. Dissolved oxygen (DO) in the aquarium decreased below 6.0 mg/L without a foam separator, but with a foam separator the average DO in the aquarium was 7.3 mg/L. Foam separation with the increase of superficial air velocity (SAV) was more effective than that with the fixed SAV. This study showed that wastewater. treatment of seawater aquarium using a foam separator is effective method for a fish waste removal and oxygen supply.

• KSBB Journal
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• v.7 no.3
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• pp.172-178
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• 1992

A simple and effective method has been developed for the immobilization of lipase producing Rhizopus chinensis on polyurethane foam. In this method, the fungal cells with 1, 3 specific lipase in there inside are immobilized within the foam matrix. Four types of commercially available polyurethane foam were tested. The ultimate purpose of the process is to produce low-cost biocatalysts for lipase-catalyzed reactions, which are being increasingly used for industrial applications. Effects of several parameters were studied on the cell loading and the hydrolytic activity of intracellular lipase after acetone drying. These parameters were the type, size, and amount of polyurethane foam. In all the cases, the intracellular lipase activity obtained with the foam was approximately twice greater than that obtained in the absence of the foam.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.37 no.3
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• pp.179-185
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• 2004

The characteristics of foam generation were assessed for freshwater and seawater using a foam generator. Both in freshwater and seawater, the height of the foam layer increased with initial protein concentrations. The height of the foam layer also increased with pore size of the air distributor. The optimum superficial air velocities (SAV) in freshwater and seawater were 0.84 cm/sec and 0.6 cm/sec, respectively. The height of the foam layer was the highest in pH 3 in freshwater and in the region of pH 5-7 in seawater. The height of the foam layer increased with $NaHCO_3$ concentration in freshwater, and $NaHCO_3$ concentration had little effect in seawater. Removal efficiencies of total suspended solid (TSS) and turbidity decreased with an increase of initial protein concentrations in a batch foam separator both in freshwater and seawater.

• Applied Chemistry for Engineering
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• v.25 no.2
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• pp.198-203
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• 2014

In this study, steam reforming reaction and surface characteristics of Ni metal foam plate were investigated. Valence state of Ni could be changed by pretreatment, and metallic Ni species exposed on surface as a active site play important role in steam reforming reaction. Porous catalytic membrane also was prepared by mixing of Ni metal foam plate and Ni-YSZ catalyst to control the pore size and assign the catalytic function in Ni metal foam plate. In SEM analysis results, Pore size of Ni metal foam plate could be controlled and Ni-YSZ catalyst well dispersed on surface. Ni based porous catalytic membrane had a similar steam reforming activity regardless of space velocity.

• Journal of Surface Science and Engineering
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• v.51 no.1
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• pp.47-53
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• 2018

Sn-based lithium-ion batteries have low cost and high theoretical specific capacity. However, one of major problem is the capacity fading caused by volume expansion during lithiation/delithiation. In this study, 3-dimensional foam structure of Cu-Sn alloy is prepared by co-electrodeposition including large free space to accommodate the volume expansion of Sn. The Cu-Sn foam structure exhibits highly porous and numerous small grains. The result of EDX mapping and XPS spectrum analysis confirm that Cu-Sn foam consists of $SnO_2$ with a small quantity of CuO. The Cu-Sn foam structure electrode shows high reversible redox peaks in cyclic voltammograms. The galvanostatic cell cycling performances show that Cu-Sn foam electrode has high specific capacity of 687 mAh/g at a current rate of 50 mA/g. Through SEM observation after the charge/discharge processes, the morphology of Cu-Sn foam structure is mostly maintained despite large volume expansion during the repeated lithiation/delithiation reactions.

• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.11 no.2
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• pp.185-192
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• 1999

Effective thermal conductivities and pressure-drop-related properties of aluminum foam metals have been measured. The effects of porosity and cell size in the aluminum foam metal are investigated in detail. The porosity of the foam metal, considered in the present study, varies from 0.89 to 0.96 and the cell size from 0.65㎜ to 2.5㎜. The effective thermal conductivity is evaluated by comparing the temperature gradient of the foam metal with that of the thermal conductivity-known material. The pressure drop in the foam metal is measured by a highly precise electric manometer while air is flowing through the aluminum foam metal in the channel. The results obtained indicate that the effective thermal conductivities are found to be increased with a decrease in the porosity while the effective thermal conductivities ire little affected by the cell size at a fixed porosity. However, the pressure drop is strongly affected by the cell size as well as the porosity. It is seen that the pressure drop is increased as the cell size becomes smaller, as expected. The minimum pressure drop is obtained in the porosity 0.94 at a fixed cell size. A new correlation of the pressure drop is proposed based on the permeability and Ergun's coefficient for the aluminum foam metal.

• Journal of Climate Change Research
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• v.9 no.4
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• pp.399-406
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• 2018

The purpose of this study is to propose a methodology for estimating greenhouse gas emission reduction through HFCs used in the foam industry. This study investigated characteristics of HFCs and greenhouse gas emissions from production processes in the foam industry, which uses HFCs as a blowing agent. Also, we investigated fluorinated gas removal technology to determine a proper technology for the foam industry. And we confirmed the criteria and characteristics of External Project for methodology development. According to criteria of External Project and foam industrial process emission, a methodology for calculating the amount of greenhouse gas emission reduction in foam industry was developed. Lastly, we analyzed the amount of greenhouse gas emission reduction and KOC (Korea Of Offset) in the foam industry based on the domestic government's plan to reduce HCFCs and imported amount of HFCs used as a blowing agent. The results of this study demonstrate that linking greenhouse gas reduction in the foam industry and the domestic greenhouse gas reduction system can contribute to achieve the domestic greenhouse gas reduction goal.