• Proceedings of the Korean Powder Metallurgy Institute Conference
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• 2006.09a
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• pp.142-143
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• 2006

Recently, automotive engines have changed to the silent chain system in order to reduce noise and to improve reliability. High contact fatigue strength is needed for the sprockets of silent chain system. As a result, a high-contact-fatigue-strength P/M material was developed using the technology of surface rolling, which densifies the surface layer of sintered parts. It was established that the contact fatigue strength of the developed material was a great improvement over that of the conventionally used sintered material.

• Journal of The Korean Society of Agricultural Engineers
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• v.53 no.6
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• pp.59-65
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• 2011

This study was performed to evaluate the compressive and flexural strength, void ratio and permeability coefficient used powdered waste glass, $CaCO_3$, recycled coarse aggregate and unsaturated polyester resin to find optimum mix design of permeable polymer concrete for pavement. The compressive and flexural strength of permeable polymer concrete for pavement using powdered waste glass were in the range of 16.8~19.7 MPa and 4.7~6.1 MPa, respectively. it was satisfied the regulation of permeable concrete for pavement (18 MPa and 4.5 MPa). The void ratio and permeability coefficient were decreased with increasing the powdered waste glass, respectively. The void ratio and permeability coefficient were satisfied national regulation of permeable concrete for pavement (8 % and $1{\times}10^{-2}$ cm/s). In addition, this study found out that required amount of binder was decreased with increasing the powdered waste glass. This fact is expected to have economical effects during the use of powdered waste glass in the manufacture of permeable polymer concrete for pavement. Accodingly, the powdered waste glass can be used for permeable concrete material.

• Journal of the Korea Safety Management & Science
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• v.21 no.4
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• pp.45-49
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• 2019

The basalt fiber is expected to become a trend for industrial fibers as they have better properties of heat-resistant, non-combustion, absorbent, soundproof, moistureproof, lightweight, corrosion resistant, and high strength properties. Also, the fiber is found to be non-toxic and harmless to the human body. Therefore, in this study, we analyzed the chemical and mineral compositions of powdered sludge of basalt produced at seven sites on Jeju Island for the development of fire resistance insulating material for a building. The results showed that the basalt stone sludge is made from only sodium calcium aluminum silicate and ferridioside components unlike the basalt rock.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2019.11a
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• pp.172-173
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• 2019

As the damage to fine dust increased, the Republic of Korea designated fine dust as a social disaster. The composition of the fine dust is composed of carbon, sulfate, nitrate, ammonium and minerals. The cause of fine dust is naturally generated by dirt, pollen, etc. In addition, there are artificial causes such as gaseous vehicle exhaust gas emitted from the use of fossil fuel. When fine dust enters the human body through breathing, it causes various respiratory diseases and skin diseases. In IARC, fine dust was designated as a carcinogen group 1. In this research, we tried to adsorb fine dust by physical adsorption using powdered activate carbon. Powdered activate carbon is a powdered activated carbon activated in a carbonized state. Porous material with high specific surface area and low density. Experimental items were tested for density, water absorption, and fine dust concentration according to the PAC addition ratio. Basic experiments were carried out to fabricate the fine dust adsorption matrix.

• Journal of Korea Technical Association of The Pulp and Paper Industry
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• v.43 no.4
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• pp.40-48
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• 2011

In this study, we investigated the usability of new powdered additives in the paperboard industry. We manufactured the powdered additives from peanut husks and garlic stems by grinding. The chemical composition, particle size, particle size distribution, and particle shape were investigated to identify the basic properties of the powdered raw materials. To determine the effect of the powdered additives on paper properties, handsheets were prepared by adding the powdered additives to the pulp slurry. The chemical composition, such as the contents of holocellulose, lignin, and ash, showed similar values to those of other biomass materials. The particles of peanut husk powder were irregularly shaped, smaller, and had a broader particle size distribution than those of the garlic stem powder, which had the fibril form. The particles of the two powdered raw materials showed a positioning of expansion in the fiber network, resulting in increased bulk and a loss of strength. Handsheets containing garlic stem particles were stronger than handsheets containing peanut husk particles. Finally, the new powdered additives are beneficial to the bulk of paperboard.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2001.11a
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• pp.58-63
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• 2001

Recently, it has been often reported that recycling of wasted glasses should be a great topic in related business circles. For the environmental reasons, a public institution are looking fur the ways of recycling these waste glasses. Consequently, the purpose of this research is to recycle crushed and powdered waste glasses by substituting for the cement in mortar and concrete. First of all, the optimum replacement ratio of Powdered Waste Glasses(PWG) can be obtained from the pilot test results. Secondary, we make advances in recycling of waste glasses as recycled to make secondary concrete products. So, we manufactured concrete brick and block contained powdered waste glasses by through mortar pilot test.

• Journal of Food Hygiene and Safety
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• v.3 no.4
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• pp.217-223
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• 1988

For the Effective utilization of the fish resources in coastal regions, investigations on preparation of powdered dried arkshell instant soup., quality stability of the products during storage and utilization as a food material were carried out with arkshell, Anadara broughtonii. Three kinds of powdered instant soup were prespared as 0% table salt(A), 5% table salt (B), 15% table salt(C) and packed with vacuum in laminated film bag. (polyester/nylon: 85${mu}ell$/15${mu}ell$, 18$\times$27cm) Their processing conditions and quality stability during storage at room temperature for 90 days were examined. Powdered instant soup was made by washing raw arkshell to remove visceral, clay, sand and blood, hot air drying(60$\pm$1$^{\circ}C$, 20 hrs) after draining and pulverizing dried arkshell to 35 mesh. Powdered instant soup was made by adding 2% sugar 0% table salt (5% and 15% table salt), 10.5% monosodium glutamate, 0.3% black pepper and 0.3% garlic powder to the pulverized dried arkshell. The condition of moisture and water activity of the products were 5.9-6.9% and 0.42-0.43, respectively. The moisture content s , water activity and pH of the products were showed little change and volatile basic nitrogen of them increased slightly during storage. Thiobarbituric acid value increased up to 60 days of storage and then decreased slightly. In solubility, powdered instant soup were showed no remarkable difference comparing with goods on the market. The color value of th products were showed little change during storage, In sensory evaluation, product B were scored slightly higher, in most cased, in flaver, color. taste and overall acceptability comparing with product A or product C during storage. Judiging form the sensory evaluation, powdered instant soup of 5% table salt (B) were the most desirable, and the quality of the products was stable for 90 days at 20$\pm$3$^{\circ}C$.

• Journal of the Korean Society of Manufacturing Process Engineers
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• v.17 no.5
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• pp.155-160
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• 2018

The materials used for 3D printing are mainly plastic and metal. These materials are usually used in the powdered form. In order to improve the surface roughness of a manufactured product, these powders should consist of small uniform spherical particles. However, the powdered forms are sold at a considerably higher price than bulk or wired materials. When a wire-type material is used instead of a powder, we can supply a relatively large amount of the material at one time as well as reduce the cost. Moreover, the use of this form of the material will increase the process efficiency. This paper deals with the technology required to feed a wire material in front of the tool movement and discusses the examples used for the verification.

• Advances in environmental research
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• v.6 no.1
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• pp.15-23
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• 2017

Powdered marble wastes (PMW) generated by Utique marble cutting industries (North of Tunisia) with abundant amounts were used in this study as low-cost materials to investigate the stabilization of heavy metals (Pb, Zn, Fe) in sludge generated from a local Zn-Electroplating factory. Powdered marble wastes were evaluated by means of chemical fractions of heavy metals in sludge and concentrations of heavy metals in leachate from columns to determine their ability to stabilize heavy metals in contaminated sludge. Results indicated that chemical fractions of heavy metals in sludge were affected by application of the PMW mineral materials and pH, however, the effects varied with heavy metals. Application of the powdered marble wastes mineral materials reduced exchangeable metals in the sequence of Pb (60.5%)>Fe (40.5%)>Zn (30.1%). X-ray diffraction and hydro-geochemical transport code PHREEQC analysis were successfully carried out to get a better understanding of the mechanisms of reactive mineral phases involved in reduced exchangeable heavy metals in sludge after PMW material amendments. Therefore, metal immobilization using powdered marble wastes materials is an effective stabilization technique for industrial metallic hydroxide sludge.

• Analytical Science and Technology
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• v.18 no.5
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• pp.436-443
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• 2005

A study of physical properties and their application using K-powdered activated carbon system followed powdered carbon dispersion was carried out at laboratory. scale. Two types of K-powdered activated carbon for the dispersion have been used in this study to investigate the catalytic removal efficiency of pollutants from the wastewater. From the surface properties obtained for carbon samples treated with aqueous solutions containing potassium salts, main investigations were subjected to isotherm shape, SEM, EDX and surface functional groups. K-powdered activated carbons were dispersed to wastewater with pH variation to investigate the removal efficiency for the color, COD, T-N and T-P. From these removal results of the piggery waste using K-powdered activated carbon, satisfactory removal performance in the region of pH 6~8 was achieved. The excellent effects for the dispersion of the K-powdered activated carbon were proved by the above mentioned properties of the material for adsorption and trapping of organics, and catalytic effects.