• 한국진공학회:학술대회논문집
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• 한국진공학회 2012년도 제43회 하계 정기 학술대회 초록집
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• pp.268-268
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• 2012

Atmospheric pressure microwave induced plasmas are used to excite and ionize chemical species for elemental analysis, for plasma reforming, and for plasma surface treatment. Microwave plasma differs significantly from other plasmas and has several interesting properties. For example, the electron density is higher in microwave plasma than in radio-frequency (RF) or direct current (DC) plasma. Several types of radical species with high density are generated under high electron density, so the reactivity of microwave plasma is expected to be very high [1]. Therefore, useful applications of atmospheric pressure microwave plasmas are expected. The surface characteristics of SUS304 stainless steel are investigated before and after surface modification by microwave plasma under atmospheric pressure conditions. The plasma device was operated by power sources with microwave frequency. We used a device based on a coaxial transmission line resonator (CTLR). The atmospheric pressure plasma jet (APPJ) in the case of microwave frequency (880 MHz) used Ar as plasma gas [2]. Typical microwave Pw was 3-10 W. To determine the optimal processing conditions, the surface treatment experiments were performed using various values of Pw (3-10 W), treatment time (5-120 s), and ratios of mixture gas (hydrogen peroxide). Torch-to-sample distance was fixed at the plasma edge point. Plasma treatment of a stainless steel plate significantly affected the wettability, contact angle (CA), and free energy (mJ/$m^2$) of the SUS304 surface. CA and ${\gamma}$ were analyzed. The optimal surface modification parameters to modify were a power of 10 W, a treatment time of 45 s, and a hydrogen peroxide content of 0.6 wt% [3]. Under these processing conditions, a CA of just $9.8^{\circ}$ was obtained. As CA decreased, wettability increased; i.e. the surface changed from hydrophobic to hydrophilic. From these results, 10 W power and 45 s treatment time are the best values to minimize CA and maximize ${\gamma}$.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 1999년도 추계학술대회 논문집
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• pp.221-223
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• 1999

In this work, samples were manufactured variously by changing conventional calcining and sintering conditions and we tried the utilization by making the heat treatment time, which is demanded to high-Tc phase formation, much shorter. We found out optimal heat treatment conditions with the analysis on formation process at superconducting phase in term of the change of calcining and sintering time and then, examined X-ray diffraction(XRD) patterns, scanning electron microscope(SEM) measurement and energy dispersive X-ray spectrometer(EDX) of the samples manufactured under heat treatment conditions which we suggest here. As a result, 2223 high-$T_c$, phase of (Bi,Pb)SrCaCuO superconductor starting with ($Bi_l$ xPbx,)$_2$$Sr_2$$Ca_2$$Cu_3$$O_y$, composition was formed from 1 hr sintering sample at temperature nearby melting point and also the completed sample with calcining and sintering time of 9 hr was formed high-$T_c$.low-$T_c$ phase appearing in sight above the critical temperature of liquid $N_2$.

• 한국축산식품학회지
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• 제18권3호
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• pp.224-231
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• 1998

In order to prepare low cholesterol cream by treatment with saponin, the optimal conditions of saponin conc., pH of saponin solution, temperature and amount of celite addition were investigated. The results revealed that the optimal conc. and pH of saponin solution were 5% and 5.5 removing 71.67% and 73.40% of cholesterol, respectively. The temperature of reaction with saponin was best at 60$^{\circ}C$, removing 74.34% of cholesterol in this condition. The addition of celite was more effective than non-addition in the removal of cholesterol from cream. The results of this study indicate that saponin is effective on cholesterol removal from cream.

• 한국의류학회지
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• 제29권9_10호
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• pp.1295-1305
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• 2005

The study was based on a three-stage, non-repetitive factorial experiment in which chemical-rotted kenaf fibers were treated separately with hydrogen peroxide concentrations of $0.5\%,\;1\%\;and\;2\%$, with pH solutions of 7, 9 and 11, and treatment times of 30, 60 and 90 minutes. Under optimal conditions, the study was conducted to determine the bleaching efficiency by the addition of chelators, penetrants and surfactants. The bleaching effects on the kenaf fibers were high in high hydrogen peroxide concentration, high in alkali solution pH, low in long treatment time. The optimal level of hydrogen peroxide on bleaching effects were at $2\%$ hydrogen peroxide concentration, with pH of 11 and treatment time of 60 minutes. Under the conditions of $2\%$ hydrogen peroxide concentration, pH 11 and treatment time of 60 minutes, the addition of chelator: Sodim Pyrophosphate(SP), Citric Acid(CA) made the bleaching effects of the kenaf fibers high.

• 한국식품영양학회지
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• 제36권2호
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• pp.129-136
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• 2023

In order to investigate the optimal UVB (ultraviolet B) treatment conditions for vitamin D₂ enhancement of freeze-dried ear mushroom, sample size (below 300 ㎛~whole), UV treatment temperature (30~60℃), treatment density (6.25~50.0 mg/cm²) and the samples mixing frequency (1~32 times) were treated differently. After that, chromaticity, vitamin D₂ and ergosterol (vitamin D₂ precursor) contents were investigated. As a result of the investigating, effective UVB treatment conditions for vitamin D₂ enhancement are as follows. The sample sizes were 2~4 mm and finely crushed pieces. The treatment temperatures were 50℃ and 60℃. The treatment density was 12.5 to 25.0 mg/cm², and the number of sample mixing was 8 times or more. As the amount of vitamin D₂ increased by UVB treatment, the ergosterol content generally tended to decrease. However, under some UVB treatment conditions, the vitamin D₂ content was not high despite the decrease of ergosterol content. Under the conditions set in this experiment, it was possible to obtain ear mushrooms with enhanced vitamin D₂ up to 26,968.7 ㎍/100 g. Therefore, it is thought that the ear mushroom is highly likely to be used as a vitamin D source and nutritionally fortified food ingredient.

• 한국건축시공학회:학술대회논문집
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• 한국건축시공학회 2016년도 추계 학술논문 발표대회
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• pp.81-82
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• 2016

The present study aims to derive optimal interface treatment conditions for emulating a monolithic construction. The joints in this construction are formed through the bonding shear evaluation method during the placement of ultra-high-performance concrete (UHPC) and normal strength concrete (NSC). The evaluation items include push-off tests for homogeneous UHPC + UHPC and heterogeneous NSC + UHPC. The experimental samples comprised a monolithic placement as the baseline, two levels for the separated placement according to the compression strength of concrete, and five levels for the interface treatment. The increase in the number of grooves and their cross-sectional areas only slightly influenced the bonding shear performance. The optimal interface treatment method for the homogeneous UHPC + UHPC construction grooves was at least 30mm. The heterogeneous NSC + UHPC construction should utilize waterjet roughening to expose the aggregate for the increased roughness.

• Applied Biological Chemistry
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• 제46권2호
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• pp.107-112
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• 2003

천마를 채취한 그대로 이용하는 데에는 생체보존에 따른 불편, 독성 그리고 자극성 등의 부작용으로 간단한 전처리 과정이 필요하다. 본 연구에서는 천마를 이용한 가공제품의 개발을 위한 전처리 과정 중 증자 조건별로 천마의 항산화적 특성을 반응 표면 분석법으로 모니터링하여 최적 증자 조건을 설정하였다. 총페놀성 화합물의 함량은 증자온도 $94.43^{\circ}C$, 증자시간 42.38min에서 최적이었고 전자 공여능은 증자온도 $101.67^{\circ}C$, 증자시간 41.09min에서 최적조건이었다. 항산화능 및 아질산염 소거능은 $100^{\circ}C$, 40min의 동일조건에서 최적으로 나타났다. 위 항산화적 특성의 증자조건을 종합하여 superimposed contour map으로 최적조건을 예측한 결과, 증자온도 96{\sim}107{\circ}C$, 증자시간 $28{\sim}46min$으로 나타났다. 예측된 임의의 증자조건 $100^{\circ}C$, 40min으로 실제 항산화 관련값을 측정한 결과 예측값의 $95.9%{\sim}115.6%$으로 유효성이 높게 나타났다.

• Clinical and Experimental Pediatrics
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• 제51권11호
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• pp.1147-1151
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• 2008

Functional urinary incontinence, the absence of any neurologic or structural abnormality as a cause of urinary incontinence in children, is one of the most common clinical problems encountered in pediatric and urologic departments, and it can be socially and emotionally distressing for the affected children. The prevalence rates of functional urinary incontinence in school-aged children are not very high and differ between boys and girls. The underlying mechanisms of functional urinary incontinence are heterogenous and can be associated with the following dysfunctions of both the storage and voiding patterns of the bladder: overactive bladder, dysfunctional voiding, lazy bladder syndrome, HinmanAllen syndrome, giggle incontinence, and vaginal voiding. Treatment methods for urinary incontinence in children should be chosen according to these clinical conditions. Treatment modalities generally consist of the treatment of comorbid conditions such as urinary infection and constipation, behavior therapy to modify learned voiding patterns, and pharmacotherapy primarily with anticholinergics and ${\alpha}$-adrenergic blockers. This review discusses the optimal treatment modalities, including treatment of the underlying voiding disorders, and diagnostic approaches related to functional urinary incontinence in children.

• 한국약용작물학회지
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• 제3권3호
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• pp.240-245
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• 1995

기내에서 직접 대량 생산하여 생산된 반하 소괴경을 인공재배할 수 있는 온도, 일장 및 생장조절제 반응 등을 검토한 결과는 다음과 같다. 1. 반하 생육에 알맞은 온도 조건은 항온보다는 변온에서 좋았다. 2. 일장 조건은 6시간/일 단일 조건에서 괴경, 물질생산 및 자구생산에 유리하였다. 3. 반하괴경의 수량은 2.4-D 0. 1ppm, Kinetin 10ppm 및 gibberellin 50ppm에서 양호 하였다. 4. 반하의 자구 형성은 2. 4-D 10ppm 과 gibberellin 10ppm에서 좋았다. 5. 콜히친 침지처리는 반하의 생육억제 효과를 나타냈으나 자구의 형성에는 콜히친 0. 05%에서 48시간 침지처리 하였을 때 가장 좋았다. 6. 콜히친 적하처리에서는 콜히친 0. 1%에서 1일 1회 적하처리할 때 괴경건물 생산량이 가장 높았고 자구형성은 콜히친 0.05%에서 매일 1회씩 5일간 적하처리할 때 가장 좋았다.

• 상하수도학회지
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• 제14권1호
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• pp.76-83
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• 2000

This research is about wastewater containing non-biodegradable TDI(Toluene Diisocyanate) that is treated by the activated carbon adsorption method. In the case of the Fenton oxidation process being applied to the existing process, optimal pH, reaction time, chemical dosing amount, removal rate, and cost were investigated. A pilot plant test was applied after finding optimal conditions with lab experiments. The optimal conditions were pH 3~5(COD removal rate 84~88%) and reaction time 30min~1hr. In higher $H_2O_2$ dosing amount, COD removal rate was a little higher. But there was little difference in the removal rate according to $FeSO_4{\cdot}7H_2O$ dosing amount. Treatment cost was economical in the case of the Fenton oxidation process being operated earlier than activated carbon adsorption system. But chemical dosing point, chemical mixing effect, chemical dosing amount, removal rate, and the cost of facility and others must be considered in practical process.