• Journal of the Korean Wood Science and Technology
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• 제35권1호
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• pp.11-16
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• 2007

본 연구는 통죽의 송풍오븐 건조중 수증기댐 처리가 건조속도 및 할렬과 외주할 예방에 미치는 영향을 조사하였다. 생재에서 함수율 약 7~8%까지 건조되는데 소요되는 시간은 건조스케줄이 과격할수록 적었으며, 건조소요시간은 건조초기의 건조속도에 의해서 크게 좌우되는 것으로 나타났다. 건조중 횡단면적 수축율과 통피층의 두께수축율은 모두 비정상적일 정도로 매우 크게 나타났다. 무처리재의 경우 건조개시 직후 할렬과 외주할이 발생하였으며, 수증기댐 처리재에서는 약 67% 정도의 건조수율을 기대할 수 있었다. 수증기댐 처리재의 외주할은 건조조건 보다는 수증기댐 처리에 의한 횡단면을 통과하는 수분의 증발 차폐정도와 밀접한 관련이 있는 것으로 평가되었다.

• 한국정밀공학회지
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• 제18권4호
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• pp.78-84
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• 2001

This study deals with the heat-treatment technique of SM45C steel with respect to less of deformation in control. The whole process for the production of landing gear must go through with uniformally controlled heat treatment, where as most deformation usually occur in nonuniform cooling environment. When a heated metal is submerged into a certain quenchant, the rate of cooling rapidity can be measured rather slow during the early stage of the procedure due to an Occurrence of a vapor blanked. As the additional course of cooling action is applied and the vapor from a vapor blanked is destroyed simultaneously, the speed of cooling promptness can be considered rather swift. The object of this study is to control the certain deformations as in the procedure of a heat treatment for landing gear by analyzing and improving the conditions of different substance of quenching liquids. Several noticeable curves indicating the temperature variation on the ap-plied metals during the cooling procedures, along with detectable rates of water verses oil and that of different polymer solutions are illustrated.

• 열처리공학회지
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• 제34권5호
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• pp.239-244
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• 2021

Following Silicon Carbide, single crystal diamond continues to attract attention as a next-generation semiconductor substrate material. In addition to excellent physical properties, large area and productivity are very important for semiconductor substrate materials. Research on the increase in area and productivity of single crystal diamonds has been carried out using various devices such as HPHT (High Pressure High Temperature) and MPECVD (Microwave Plasma Enhanced Chemical Vapor Deposition). We hit the limits of growth rate and internal defects. However, HFCVD (Hot Filament Chemical Vapor Deposition) can be replaced due to the previous problem. In this study, HFCVD confirmed the distance between the substrate and the filament, the accompanying growth rate, the surface shape, and the Raman shift of the substrate after vapor deposition according to the vapor deposition temperature change. As a result, it was confirmed that the difference in the growth rate of the single crystal substrate due to the change in the vapor deposition temperature was gained up to 5 times, and that as the vapor deposition temperature increased, a large amount of polycrystalline diamond tended to be generated on the surface.

• Journal of the Korean Wood Science and Technology
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• 제40권2호
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• pp.61-70
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• 2012

In this study the effect of heartwood-coating (HCO), vapor-dam (VD), bark-remaing (BR) and bark-remaining- coating (BRC) treatments were evaluated during air circulating oven-drying of hollowed round-post of Korean red pine. Hollowed round-post could be dried from the green condition to approximately 6% MC within 84 to 156 hours for the UC, HCO and VD specimens and it took 72 to 240 hours to about 8% MC, which is recommended as the indoor in-use MC. The temperatures in the hole of the Control (UC) and HCO specimens constantly showed a higher-leveled distribution pattern than those inside wood. The vapor pressure in the hole of the UC, HCO and BR specimens was higher than that inside wood and showed difference as highest value of about 20 mbar. The surface checks of all specimens were mild and were observed in increasing order of BRC, BR, UC, VD and HCO specimens.

• 대한금속재료학회지
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• 제49권4호
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• pp.334-341
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• 2011

The mechanism behind super-filling of high-aspect-ratio features with Cu by catalyst-enhanced chemical vapor deposition (CECVD) coupled with plasma treatment is described and the metrology required to predict the filling feasibility is identified and quantified. The reaction probability of a Cu precursor was determined as a function of substrate temperature. Iodine adatoms are deactivated by the bombardment of energetic particles and also by the overdeposition of sputtered Cu atoms during the plasma treatment. The degree of deactivation of adsorbed iodine was experimentally quantified. The quantified factors, reaction probability and degree of deactivation of iodine were introduced to the simulation for the prediction of the trench filling aspect by CECVD coupled with plasma treatment. Simulated results show excellent agreement with the experimental filling aspects.

• 한국식품저장유통학회지
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• 제30권4호
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• pp.549-561
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• 2023

Recently, consumers have gained an interest in natural and minimally processed foods, inciting the food industry to consider using of natural products as preservatives. Strawberries are a widely consumed fruit but are also highly perishable. Therefore, in this study, the physicochemical properties of strawberries (Fragaria×ananassa) were evaluated after a 12-h treatment with lemon essential oil (Citrus×limon) or cinnamon essential oil (Cinnamomum cassia) vapor during storage at 22℃ for 4 days in an accelerated shelf-life study and 4℃ for 18 days in a validation study. Weight loss was blunted in fruit treated with oil vapor during the first days of storage (p<0.05). Lemon essential oil delayed fruit darkening (p<0.05) but reduced the firmness of strawberries (p<0.05). Strawberries treated with cinnamon essential oil had a higher concentration of reducing sugars (p<0.05), and a decrease of 16.7% visible decay, although the difference was insignificant. Oil vapor treatment did not alter the pH, organic acid content, or soluble solid content during storage compared to the control. Since lemon and cinnamon essential oils have well-documented antimicrobial properties, they may be suitable for the natural preservation of fruit. This study provides new information on using essential oil vapor treatment to preserve fruits, and potentially decrease fruit loss and waste.

• Bulletin of the Korean Chemical Society
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• 제33권3호
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• pp.825-827
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• 2012

In this study, the variation in surface morphology of copper phthalocyanine (CuPc) thin films treated with a flow of acetone vapor assisted by nitrogen carrier gas was investigated. The CuPc nanorods with similar dimensions were well dispersed throughout the whole film surfaces after ~20 min. of treatment. However, the electronic absorption spectra only changed slightly, which indicates that molecular stacking was not altered during treatment. This treating method is simple and more advantageous compared to other solvent treating technologies such as mixed solvent spray treatment using organic solvents and water since it requires relatively mild treating conditions and does not need the presence of water.

• 한국정밀공학회:학술대회논문집
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• 한국정밀공학회 2012년도 춘계학술대회 논문집
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• pp.499-500
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• 2012

• 열처리공학회지
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• 제28권1호
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• pp.7-16
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• 2015

The fabrication of high quality graphene using chemical vapor deposition (CVD) method for application in semiconductor, display and transparent electrodes is investigated. Temperature and pressure have major impact on the growth of graphene. Graphene doping was obtained by deposition of $MoO_3$ thin films using thermal evaporator. Bilayer graphene and the metal layer graphene were obtained. According to the behavior of graphene growth P-type doping was confirmed. Graphene obtained through experiments was analyzed using optical microscopy, Raman spectroscopy, UV-visible light spectrophotometer, 4-point probe sheet resistance meter and atomic force microscopy.

• 한국연소학회:학술대회논문집
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• 한국연소학회 2001년도 제22회 KOSCI SYMPOSIUM 논문집
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• pp.106-118
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• 2001

A rigorous study of single droplet vaporization under quiescent high pressure atmosphere is attempted adopting method of flash evaporation calculation for vapor-liquid equilibrium. Results due to flash method shows excellent agreement with measurement. Also shown is the present model fairly capable of depicting transients of droplet vaporization under high pressure environment, such as ambient gas solubility, property variation, and multicomponent transports. Systematic treatment of these effects with emphasis on vapor-liquid phase equilibrium revealed; conventional treatment for subcritical droplet vaporization, such as $d^2$-law, leads to erroneous prediction of droplet history, augmented gas solubility is significant under supercritical pressure, and vaporization rate proportionally increase with pressure.