• Korean Journal of Materials Research
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• v.2 no.5
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• pp.375-382
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• 1992

Molybdenum silicide films have been prepared by sputtering from a single composite MoS$i_2$ source on both P, B$F_2$respectively implanted (5${\times}10^{15}ions/cm^2$ single crystal and P implanted (5${\times}10^{15}ions/cm^2$) polycrystalline silicon substrates followed by rapid thermal annealing in the ambient of argon. The heat treatment temperatures have been varied in the range of 600-l20$0^{\circ}C$ for 20 seconds. The properties of Mo-silicide and the diffusion behaviors of dopant after the heat treatment are investigated using X-ray diffraction, scanning electron microscopy(SEM) , secondary ions mass spectrometry(SIMS), four-point probe and $\alpha-step.$ Annealing at 80$0^{\circ}C$ or higher resulted in conversion of the amorphous phase into predominantly MoS$i_2$and a lower sheet resistance. There was no significant out-diffusion of dopants from both single crystal and polycrystalline silicon substrate into molybdenum silicide layers during annealing.

• Food Engineering Progress
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• v.21 no.1
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• pp.22-28
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• 2017

Ginger was steamed at $121^{\circ}C$ and $1.5lb/in^2$ for 30 min, dried at $60^{\circ}C$ for 12 h, and each step was repeated nine times. During processing, the lightness ($L^*$ value) and yellowness ($b^*$ value) decreased from $85.65{\pm}0.33$ and $26.99{\pm}0.20$ in the non-treated ginger to $56.91{\pm}0.25$ and $16.69{\pm}0.06$ in ginger treated for the ninth treatment. On the other hand, redness ($a^*$ value) increased from $-1.51{\pm}0.03$ to $7.34{\pm}0.08$ on the eight treatment and then decreased to $7.21{\pm}0.04$ on the ninth theatment. The contents of 6-gingerol decreased from $3.257{\pm}0.067mg/g$ in the non-treated ginger to $0.567{\pm}0.036mg/g$ on the theatment, whereas the contents of 6-shogaol increased from $1.299{\pm}0.050mg/g$ to $2.999{\pm}0.089mg/g$ on the sixth treatment and decreased to $2.099{\pm}0.039$ on the ninth treatment. The contents of 10-gingerol decreased slightly from $1.106{\pm}0.125mg/g$ to $0.806{\pm}0.026mg/g$. Unlike the 6- and 10-gingerol, the contents of 8-gingerol did not change greatly, with values between $0.916{\pm}0.005mg/g$ and $1.106{\pm}0.005mg/g$ being observed during processing. The tyrosinase inhibitory activities were increased from $43.42{\pm}11.45%$ in the non-treated ginger to 100% on the sixth treatment and then decreased to $51.98{\pm}7.36%$ on the theatment. The antioxidative activity was retained during processing.

• Korean Journal of Materials Research
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• v.4 no.3
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• pp.357-363
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• 1994

The irradiation growth of the Zircaloy-4 cladding in the KOFA fuel loaded in the Kori-2 nuclear plant was measured to evaluate the irradiation growth behavior and to be compared with that of the Siemens cladding having different manufacturing process. Due to the partial recrystallization by final heat treatment, the KOFA Zircaloy-4 cladding showed a two step irradiation growth behavior such as the growth saturation and the accerlation which is typical of the fully annealed Zircaloy cladding. The difference in the measured irradiation growth rate between the KOFA and the Siemens cladding could be explained by the difference in the cladding texture which depends on the manufacturing process. From the measured irradiation growth data of Kori-2 KOFA fuel, a two-step irradiation growth model of the KOFA Zircaloy-4 cladding was derived, the accuracy of which can be more clearly verified as the measured data of the irradiation growth are accumulated in the future.

• Journal of the Korean Society of Manufacturing Process Engineers
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• v.7 no.3
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• pp.75-80
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• 2008

The progressive die performs a work of sheet metal processes with a piercing, notching, embossing, bending, drawing, cut-off etc. in many kinds of pressing. Now a days, these processes have been evaluated as a advanced tooling method to increase the productivity and high quality assurance. The first step analyzing of die design is production part review, then the arrangement drawing of product design and strip process layout design should be done as a next steps with a FEM simulation for its problem solution. After upper procedure were peformed, it was started to make the die, then tryout and its revision of the die and product quality, safety, productivity etc. were done continually. For the all of these process, we mobilized the theory and practice of sheet metal forming, die structure, the function and activity of die components, and the others of die machining, die material, heat treatment and know‐how so on. In this study the features of representative are production part analyzing through the FEM simulation of bending area with a considering spring back problem by DEFORM.

• Journal of Applied Biological Chemistry
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• v.51 no.3
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• pp.95-101
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• 2008

The gene encoding a putative esterase of Xanthomonas oryzae pv. oryzae was cloned using PCR technique. The gene was expressed with His6 tag in E. coli. One-step purification of the recombinant esterase with Ni-NTA resin resulted in one band by SDS-PAGE analysis. The purified enzyme showed a molecular weight of 30 kDa, as expected, therefore the enzyme was a mononer. The enzyme was the most active toward p-nitrophenyl (p-NP) acetate and p-NP-butyrate to a lesser extent. However, the enzyme could not hydrolyze p-NP-myristate, palmitate, and stearate. Therefore, the enzyme is considered as an esterase, very different from lipase. The purified esterase had optimal pH at around 8.0 and was stable in a broad range of pH values. The optimal temperature ranged from 30 to $40^{\circ}C$, and the residual activity observed after heat treatment at $55^{\circ}C$ for 20 min was 72 % of the initial activity. The activity was inhibited by the presence of copper and cobalt ions.

• Proceedings of the Materials Research Society of Korea Conference
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• 2003.03a
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• pp.53-53
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• 2003

There has been increasing interest in the fabrication of nano-sized structures because of their various advantages and applications. Anodic Aluminum Oxide (AAO) is one of the most successful methods to obtain highly ordered nano pores and channels. Also It can be obtained diverse pore diameter, density and depth through the control of anodization condition. The three types of substrates were used for anodization; sheets of Aluminum on Si wafer and Aluminum on Mo-coated Si wafer. In Aluminum sheet, a highly ordered array of nanoholes was formed by the two step anodization in 0.3M oxalic acid solutions at 10$^{\circ}C$ After the anodization, the remained aluminum was removed in a saturated HgCl$_2$ solution. Subsequently, the barrier layer at the pore bottom was opened by chemical etching in phosphoric acid. Finally, we can obtain the through-channel membrane. In these processes, the effect of various parameters such as anodizing voltage, anodizing time, pore widening time and pre-heat treatment are characterized by FE-SEM (HITACH-4700). The pore size. density and growth rate of membrane are depended on the anodizing voltage and temperature respectively. The pore size is proportional to applied voltage and pore widening time The pore density can be controlled by anodizing temperature and voltage.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 1995.11a
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• pp.340-342
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• 1995

We prepared $LiCo_{1-x}Ni_{x}O_2$ by reacting stoichiometric mixture of LiOH.$H_2O$, $CoCO_3$.$xH_2O$ and $Ni(OH)_2$(mole ratio respectively) and heating at $850^{\circ}C$ for 5n. In the result of X-ray diffraction analysis, along fluctuation of the function of x in $LiCo_{1-x}Ni_{x}O_2$(003) peak and (104) peak indensities and ratio were varied. We awared through XRD that from 0 to 0.5 at x in $LiCo_{1-x}Ni_{x}O_2$ is well formed for hexagonal structure at one step heat treatment($850^{\circ}C$), but if Ni involve at $LiCo_{1-x}Ni_{x}O_2$ hexagonal structure is not well formed. In the result of charge/discharge tests charge/discharge capacity and effiency is different about various cathode. Therefore, the appropriate charge/discharge method must be selected for good characteristics.

• Journal of the Korean Ceramic Society
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• v.33 no.8
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• pp.855-862
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• 1996

The nucleation and the crystal growth rates of Ge-Se-Te chalcogenide glass by two step heat-treatment and its effect on the mechanical optical properties and water-resistance were determined. The maximum nuclea-tion and crystal growth rate were 2.1$\times$103/mm3 .min at 28$0^{\circ}C$ and 0.4${\mu}{\textrm}{m}$/min at 33$0^{\circ}C$ respectively. When the crystal volume fraction with crystal size $1.5mutextrm{m}$ was about 4% the (hardness and fracture toughness were about 117kg/mm2 and 6.0 MPa.mm1/2)respectively. The weight loss of crystallized glass in water was lower than parent glass($25^{\circ}C$ for 32 hrs : 0.03% 8$0^{\circ}C$ for 16 hrs : 0.1%) as 0.01% at $25^{\circ}C$, 0.03% at 8$0^{\circ}C$ for 16 hrs : 0.1%) at $25^{\circ}C$ 0.03% at 8$0^{\circ}C$ respectively. The IR-transmittance decreased with increasing crystal size and crystal volume fraction. The IR-transmittance of crystallized glass with the crystal size of $1.5mutextrm{m}$ (crystal volume fraction : 4%) presented 56% which was about 4% lower than that of parent glass.

• Resources Recycling
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• v.9 no.2
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• pp.3-10
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• 2000

Used aluminum beverage can(UBC) is an important secondary resource. Domestic recycling rate of UBC should be increased from the standpoint of resource savings and environmental protection. Aluminum can to can recycling is divided into two steps. The first step was composed of the processes such as collection of used beverage cans, shredding, magnetic separation, de-lacquring, melting and casting. The second is remelting and casting, heat treatment, hot and cold rolling, annealing, and can making. With brief discussion about this recycling technology, this article covers aluminum can consumption, the present state of aluminum can recycling in Korea, Japan, USA, and Europe.

• Journal of the Korean Chemical Society
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• v.65 no.2
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• pp.125-132
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• 2021

An electrochromic nickel oxide thin film was fabricated on a flexible PET/ITO substrate using a nanocrystallite- dispersed coating sol and bar coater. Nanocrystalline NiOx of 3-4 nm crystallite size was first synthesized by base precipitation and thermal conversion. This NiOx nanocrystallite powder was mechanically dispersed in an alcoholic solvent mixed with a silane binder to prepare a coating sol for thin film. This sol method is different from the normal sol-gel method in that it does not require the conversion of precursor by heat treatment. Therefore, this method provides a very facile method to prepare NiOx thin films on any kind of substrate and it can be easily applied to mass production. The electrochromic performance of this NiOx thin film on PET/ITO electrode with a thickness of about 400 nm was investigated in a nonaqueous LiClO4 electrolyte solution by cyclic voltammetric and repeated chronoamperometric measurements in conjunction with spectrophotometry. The visible light modulation of 44% and the colorization efficiency of 41 ㎠/C at 550 nm were obtained at the step potentials of -0.8/+1.2 V vs Ag and a duration of 30 s.