• Proceedings of the Korean Institute of Surface Engineering Conference
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• 2012.05a
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• pp.218-219
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• 2012

Carbon coils could be synthesized using $C_2H_2/H_2$ as source gases and $SF_6$ as an incorporated additive gas under thermal chemical vapor deposition system. Prior to the carbon coils deposition reaction, two kinds of samples having different combination of Ni catalyst and substrate were employed, namely a commercially-made $Al_2O_3$ ceramic boat with Ni powders and a commercially-made $Al_2O_3$ substrate with Ni layer. By using a commercially-made $Al_2O_3$ ceramic boat, the production yield of carbon coils could be enhanced as much as 10 times higher than that of $Al_2O_3$ substrate. Furthermore, the dominant formation of the microsized carbon coils could be obtained by using $Al_2O_3$ ceramic boat.

• Journal of Korea Foundry Society
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• v.12 no.4
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• pp.305-316
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• 1992

Steel and iron castings made with expandable polystylene (referred to hereafter as EPS) patterns are often affected by distinctive defects associated with incomplete decomposition of the EPS as the molds are filled with metal. The effects of practical factors on carbon pick-up were investigated on the specimens, by taking successive layers of swarf and analysis, whereas the lustrous carbon is determined by using combustion analysis. The quality of the castings, with particular reference to carbon pick-up in low carbon steel and lustrous carbon on gray iron, is further influenced to a significant extent by such practical factors as reduced pressure, the pouring temperature, the density of EPS pattern, the additive in coating and in pattern and the casting thickness. The rate at which carbon pick-up and lustrous carbon deposites are formed can be reduced by reducing the density of the pattern and also reducing pressure, especially by adding $Na_2CO_3$ in coating and in pattern to promote $CO_2$ evolution. The upper parts of castings obtained using EPS patterns are slightly higher in carbon pick-up and in lustrous carbon than other parts.

• Journal of Integrative Natural Science
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• v.12 no.4
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• pp.116-121
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• 2019

This experiment is to evaluate the physical properties of the hydrogel lens with the addition of carbon-based nanomaterials, Graphene oxide and Carbon nanotube, and to confirm the improvement of strength. Hyaluronic acid, a hydrophilic substance, was used as an additive by using HEMA (2-hydroxyethyl methacrylate) and ethylene glycol dimethacrylate (EGDMA) as a base monomers. Graphene oxide and two types of Carbon nanotubes(Amide functionalized and Carboxilic acid functionalized) were added 0.1%, 0.3%, 0.5%, respectively, and the physical properties were analyzed by measuring water content, refractive index, breaking strength and SEM image. In the case of the sample added with each carbon nano material, the water content tended to increase for all three materials. The breaking strength tended to increase in Graphene oxide and Carbon nanotube; Carboxilic acid functionalized, but in the case of Carbon nanotube; amide fuctionalized, the breaking strength tended to decrease. However, Carbon nanotube; amide fuctionalized had the highest breaking strength among the three nano materials. Thus, the addition of certain carbon nanomaterials seems to be appropriate for improving the strength of hydrogel lenses.

• 한국신재생에너지학회:학술대회논문집
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• 2010.11a
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• pp.165.1-165.1
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• 2010

In the past, drivers bought a fuel additives to treat a combustion chambers or injector nozzles for carbon or gum deposit at market. But, nowadays, as raised cost of fuel for a vehicle the consumers also start focusing on a function of fuel additives that increases fuel economy of one. Some fuel additive manufacturers and agents advertise that their goods make a car it's initial state. This paper shows data for 3 years that were acquired during test for registration of an additive in domestic. The data were sorted according to kind of vehicle, kind of fuel, test mode, CO, HC, NOx, PM, total emission, fuel economy and accumulated mileage. And than by using simple linear regression analysis changes according to accumulated mileage was displayed. Normal distribution and histogram of rate of increase and decrease were displayed. the analyzed data indicated that a fuel additive maintain and make a car the first state of one but can't make a car be batter than initial the one.

• Journal of the Korean Ceramic Society
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• v.25 no.5
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• pp.561-569
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• 1988

Mixtures of very small amounts of additive, carbon and silica(about 0.46${\mu}{\textrm}{m}$) which synthesized by the hydrolysis of ethyl silicate, the molar ratio of SiO2/C was fixed to 1/10, was nitrided at 145$0^{\circ}C$. It was considered that the optimum amount of additive to promote the nitridation reaction was below 2.0wt%. By the addition of additive, the nitridation reaction was promoted and formation of $\beta$-Si3N4 was promoted at 145$0^{\circ}C$ for 1hour, but, the nitridation reaction was decreased and the ratio of $\alpha$/$\beta$ of Si3N4, was increased at 145$0^{\circ}C$ for 5 hours. The crystal phase was $\alpha$ phase and the nitridation reaction was promoted and the particle size of silicon nitride was become smaller by the addition of $\alpha$-Si3N4, but silicon nitride of whisker-like form was produced by the addition of transition elements. There was a difference in the lattice constants of $\alpha$-Si3N4, but no difference in its of $\beta$-Si3N4 according to kinds of added substance and reaction time.

• Journal of the Korean Crystal Growth and Crystal Technology
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• v.23 no.6
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• pp.296-301
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• 2013

Carbon coils could be synthesized using $C_2H_2/H_2$ as source gases and $SF_6$ as an incorporated additive gas under the thermal chemical vapor deposition system. A 304-type stainless steel was used as a substrate with nickel powders as the catalyst. The surface of the substrate was pretreated using a sand paper or a mechanical drill to enhance the production yield of the carbon coils. The characteristics of the deposited carbon nanomaterials on the substrates were investigated according to the surface state on the stainless steel substrate. The protrusion induced by the grooves on the substrate surface could enhance the formation of the carbon nanomaterials having the coils geometries. The cause for the enhancement of the carbon coils formation by the grooves was suggested and discussed with the surface energies for the interaction between as-growing carbon elements. Finally, we could obtain the massive production yield of the carbon coils by the surface pretreatment using SiC sand papers on the several tens grooved stainless steel substrate.

• Journal of Mechanical Science and Technology
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• v.15 no.6
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• pp.804-812
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• 2001

A triboelectrostatic separation system for removing unburned carbon from coal fly ash is designed and evaluated. Fly ash from a coal-fired power plant is used as an accepted additive in concrete where it adds strength, sulfate resistance and reduced cost, provided acceptable levels of unburned carbon are maintained. Unfortunately, unburned carbon in coal fly ash absorbs some of other additives and reduces the concrete strength. This paper describes to investigate dry triboelectrostatic process to separate unburned carbon from coal fly ash and utilize it into economically valuable products. The laboratory-scale triboelectrostatic separation system consists of a particle feeding system, a tribocharger, a separation chamber, and collection systems. Particles of unburned carbon and fly ash can be imparted positive and negative surface charges, respectively, with a copper tribocharger due to differences in the work function values of the particles and the tribocharger, and can be separated by passing them through an external electric field. Results showed that fly ash recovery was strongly dependent on the electric field strength and the particle size. 70wt% of fly ash containing 6.5wt% of carbon contents could be recovered at carbon contents below 3%. The triboelectrostatic separation system showed a potential to be an effective method for removing unburned carbon from coal fly ash.

• Journal of the Korean Applied Science and Technology
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• v.30 no.3
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• pp.423-430
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• 2013

Carbon coils could be synthesized using $C_2H_2/H_2$ as source gases and $SF_6$ as an incorporated additive gas under thermal chemical vapor deposition (CVD) system. Prior to the carbon coils deposition reaction, two kinds of samples having different combination of Ni catalyst and substrate were employed, namely, a commercially-made $Al_2O_3$ ceramic boat with Ni powders and a commercially-made $Al_2O_3$ substrate with Ni layer. By using a commercially-made $Al_2O_3$ ceramic boat, the synthesis of carbon coils could be enhanced as much as 10 times higher than that of $Al_2O_3$ substrate. Furthermore, the dominant formation of the microsized carbon coils could be obtained by using $Al_2O_3$ ceramic boat. The surface roughness of the supporting substrate of $Al_2O_3$ ceramic boat was understood to be associated with the large scale synthesis of carbon coils as well as the dominant formation of the larger-sized, namely the microsized carbon coils.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 1995.11a
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• pp.198-201
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• 1995

Carbons are the materials which are known to be usable at highest temperature in existing materials and are being increased their mechanical Properties to 2000$^{\circ}C$. They have many advantageous characteristics such as electrical and thereat conductivity. But, inspire of their properties, this materials have covalant bonding that strong1y link their atoms. the covalant bondings are too strong to occur atomic diffusions or shirinkages during the sintering. because of this sintering mechanism, carbon materials must be produced by using some binders. To obtain a good carton material, it is important that the function of binders. And to obtain a good binder, it reqired the additive which can improve the properties of the binder, so called curing agent. In this study, we make a curing agent that can improve the properties of binders to evaluate the yield of carbon from binders and to shirink the substrate. and compared the carbon materials treated with the binder containing the curing agent to that treated with common binder.

• ETRI Journal
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• v.38 no.2
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• pp.252-259
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• 2016

Di(1-aminopyrene)quinone (DAQ) as a quinone-containing conducting additive is synthesized from a solution reaction of 1-aminopyrene and hydroquinone. To utilize the conductive property of DAQ and its compatibility with activated carbon, a composite electrode for a supercapacitor is also prepared by blending activated carbon and DAQ (3:1 w/w), and its supercapacitive properties are characterized based on the cyclic voltammetry and galvanostatic charge/discharge. As a result, the composite electrode adopting DAQ exhibits superior electrochemical properties, such as a higher specific capacitance of up to $160F{\cdot}g^{-1}$ at $100mV{\cdot}s^{-1}$, an excellent high-rate capability of up to $1,000mV{\cdot}s^{-1}$, and a higher cycling stability with a capacitance retention ratio of 82% for the 1,000th cycle.