• Journal of Advanced Marine Engineering and Technology
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• 제39권6호
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• pp.662-669
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• 2015

해저 석유생산시스템에서 빈번히 발생하는 왁스집적 문제는 안정적인 석유 생산을 방해하고 높은 비용을 발생시키므로 왁스집적 제어에 대한 관심이 증가하고 있다. 왁스집적 제어를 통한 석유의 유동안정성 확보를 위해서는 왁스집적거동을 신뢰성 있게 예측해야 한다. 이 연구에서는 왁스집적 거동에 큰 영향을 미치는 분자확산, 전단응력효과, 왁스경화 메커니즘을 시뮬레이션 기술에 적용하여 불확실도가 높은 변수인 전단응력계수, 왁스고형물의 공극률, 왁스 열전도도, 분자확산계수와 물과 가스 양이 왁스집적 거동에 미치는 영향에 대한 분석을 단상과 다상 유동 시 층류 유동 조건에서 수행하였다. 그 결과 왁스고형물의 공극률과 분자확산계수가 높아질수록, 전단응력계수가 낮아질수록 왁스집적 두께가 두꺼워지는 것을 확인할 수 있었고 석유의 온도가 왁스집적 위치에 주요하게 영향을 미치는 것으로 판단된다. 물의 양에 따른 왁스집적 시뮬레이션 결과 기존 연구에서 다소 다른 결과들이 존재하나 이 연구 조건에서는 물의 양 40%까지 왁스집적량이 증가하다 감소하는 것을 확인하였고 가스 양이 많아질수록 유체의 액상 내 가벼운 탄화수소 농도 감소로 인해 왁스집적량이 증가하는 것을 파악하였다. 이 연구결과는 향후 현장 또는 현장을 모사한 실험시스템에서의 결과와 시뮬레이션 결과를 매칭하여 해저 유동관에서 왁스집적 거동을 예측하는데 효과적으로 적용될 수 있을 것으로 사료된다.

• 대한화장품학회지
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• 제36권2호
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• pp.99-103
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• 2010

왁스 또는 긴사슬을 가지는 탄화수소는 동물, 식물, 광물 또는 합성에 의해 만들어 진다. 오일-왁스 겔은 립스틱과 같은 다양한 화장품 분야에 사용되어지고 있다. 예를 들면, 립스틱의 사용감촉은 오일-왁스 겔의 광택 정도에 크게 영향을 받는다. 여러 논문에서 단일 용매 또는 혼합된 용매에서의 왁스 구조에 대해서 연구가 진행되었다. 그러나 왁스 구조에 대한 연구 논문은 극히 소수에 불과하다. 이 논문의 목적은 세레신 왁스와 또 다른 왁스를 사용하여 오일-왁스 겔에서의 광택과 왁스 구조에 대한 관계를 연구하였다. 최근 들어 입술피부에서의 광택 효과는 아름다움의 척도로 알려지고 있다. 광택효과는 오일-왁스 메트릭스가 형성될 때 메트릭스 구조의 변화와 오일의 성질에 의해 좌우된다. 최근 연구에서는 세레신 왁스와 마이크로크리스탈린 왁스로부터 얻어진 오일-왁스 겔에서의 왁스 구조변화와 그에 따른 광택에 대한 영향을 보고하고 있다.

• BMB Reports
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• 제42권6호
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• pp.367-372
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• 2009

In this study, we showed that WAX9D, a nonspecific lipid-transfer protein found in broccoli, binds palmitate (C16) and stearate (C18) with dissociation constants of 0.56 ${\mu}M$ and 0.52 ${\mu}M$, respectively. WAX9D was fused to thioredoxin protein by genetic manipulation to enhance its solubility. The data revealed strong interaction of Trx-WAX9D with palmitate and stearate. The dissociation constants of Trx-WAX9D for palmitate and stearate were 1.1 ${\mu}M$ and 6.4 ${\mu}M$, respectively. The calculated number of binding sites for palmitate and stearate was 2.5 to 2.7, indicating that Trx-WAX9D can bind three molecules of fatty acids. Additionally, Trx-WAX9D was shown to inhibit the apoptotic effect of palmitate in endothelial cells. Our data using Trx-WAX9D provide insight into the broad spectrum of its biological applications with specific palmitate binding.

• Journal of Advanced Marine Engineering and Technology
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• 제38권10호
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• pp.1333-1339
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• 2014

As the demand for petroleum resources increases, and oilfields on lands and in shallow-sea become exhausted, the areas for oil production are expanding to the deep sea and therefore technologies for flow assurance are coming into the highlight. In low temperature environment such as the deep sea, wax is accumulated and prevents stable oil production. Therefore, the development of flow assurance technologies is required. Wax is precipitated in crystalline form when the oil temperature decreases below the wax appearance temperature; it then accumulates on the inner walls of pipelines causing blockages. In particular, in subsea pipelines, which have a large surface contact area with the surrounding seawater, wax deposition problems are frequent. The internal tubular coating can effectively reduce wax deposition without pausing oil production when the coating is appropriately designed. This study carried out wax deposition tests on a number of internal tubular coatings under single flow conditions. The results were analyzed for the effects that the physical properties of the coatings had on wax deposition.

• KSBB Journal
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• 제27권5호
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• pp.319-323
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• 2012

Vitamin C or L-ascorbic acid, an essential nutrient for humans with antioxidative property, was coated with natural wax to be used as functional additives for cosmetics. Coating of vitamin C was performed using carnauba wax and olive wax in self-designed reaction chamber for 60 min. The yield of coated vitamin C with carnawuba wax and olive wax were up to $94.6{\pm}1.2%$ and $82.5{\pm}1.4%$, respectively. The stability of the carnauba wax-coated vitamin C in the lotion was improved 17.8% than that of uncoated vitamin C during 30 day storage at $25^{\circ}C$. Color and the layer separation of the lotion added with the coated vitamin C showed better property than with the uncoated vitamin C. The coated vitamin C can be applied to cosmetic ingredients as a stable additive.

• 한국자동차공학회논문집
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• 제10권6호
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• pp.142-149
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• 2002

The frictional properties of nylon can be improved by the impregnation of lubricants like wax, oil or graphite. The inclusion of these lubricants, on the other hand, decreases the mechanical properties of nylon, such as tensile strength, hardness and impact strength. As an attempt to maximize frictional properties, while minimizing a decrease in the mechanical properties, various kinds of nylon containing 3 wt% wax and varying contents of oil or graphite were prepared. It was found that the synergy effects to improve both friction and anti-wear properties is evidenced by impregnating a combination of wax/oil or wax/graphite. The wear rate of a nylon containing 3 wt% of wax and 1.5 wt% of oil turned out to be 1/4 of that of nylon impregnated with 8 wt% wax or 8 wt% oil. The latter showed the lowest wear rate among the nylons prepared with a single lubricant. In addition, the friction coefficient of the developed nylon was found to be very similar to the nylon with 8 wt% wax only.

• 한국기계가공학회지
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• 제10권6호
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• pp.146-151
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• 2011

Wax spin coating is a part of several wafer handling processes in the silicon wafer polishing station. It is important to ensure the wax layer free of contamination to achieve the high degree of planarization on wafers after wafer polishing. Three-dimensional air flow characteristics in a wax spin coater are numerically investigated using computational fluid dynamics techniques. When the bottom of the wax spin coater is closed, there exists a significant recirculation zone over the rotating ceramic block. This recirculation zone can be the source of wax layer contamination at any rotational speed and should be avoided to maintain high wafer polishing quality. Thus, four air suction ducts are installed at the bottom of the wax spin coater in order to control the air flow pattern over the ceramic block. Present computational results show that the air suction from the bottom is quite an effective method to remove or minimize the recirculation zone over the ceramic block and the wax coating layer.

• 한국식품영양학회지
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• 제15권2호
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• pp.131-136
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• 2002

동아의 단백질 가수분해효소 활성은 익은 동아 육질은 0.19 unit/0.5ml, 어린 동아 육질은 0.56unit, 익은 동아속은 24.35unit, 어린 동아속은 0.35unit이었다. 생고기에 대한 활성은 익은 동아 육질은 생쇠고기에 대해서는 13.0unit, 생돼지고기에 대해서는 7.4unit를 나타냈고, 동아속은 생쇠고기에 대해서는 30.2unit, 생돼지고기에 대해서는 24.5unit를 나타냈다. 단백질 가수 분해효소의 열 안정성은 각 온도별에서 10분간 가열한 다음 7$0^{\circ}C$까지는 안정하였고, 8$0^{\circ}C$에서는 21%의 활성만 남고, 9$0^{\circ}C$ 이상에서는 활성을 잃었다. 분광광도 스펙트럼 결과는280nm에서의 단백질 피크가 주이고, 다른 흡광성 물질은 없었다. HPLC분석 결과, 익은 동아와 어린 동아 육질과 속은 모두 단백질 가수분해효소 작용으로 casein을 작은 분자로 가수분해하였다. 1/10로 희석한 것은 카제인이 가수분해된 것과, 엉겨서 분자량이 커진 것 두 가지인데 반해 1/10희석한 익은 동아속은 분자량이 커진 것은 나타나지 않았다. 그리고, 1/10 희석한 것은 원액을 사용한 것과 모습이 다르지만 익은 동아속은 원액과 패턴이 같았다.

• Journal of Nutrition and Health
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• 제36권4호
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• pp.335-343
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• 2003

This study was designed to investigate the hypoglycemic effects of Benincasa hispida (Wax gourd) in streptozotocin (STZ)-induced diabetic rats. Diabetes was induced in the male rats by intravenous injection of STZ at a dose of 45 mg/kg dissolved in citrate buffer. The diabetic animals then had plasma glucose concentration of above 300mg/dl. The experimental groups were divided into five groups; normal, STZ-control and three Wax gourd groups (5%, 10% and 20% intake groups). Normal and STZ-control groups were fed on a AIN-93 diet and experimental groups were fed a AIN-93 diet with the Wax gourd powder (5%, 10% and 20%/kg diet) for 4 weeks. The body weight, diet intake and feed efficiency ratio (FER) were monitored. The blood glucose and cholesterol levels were determined everyweek. After 4 weeks, the rats were sacrificed and the levels of glucose, insulin, cholesterol, HDL-cholesterol, triglyceride and free fatty acids in plasma and levels of glycogen in liver and muscle were analyzed. Diabetic rats showed the lower weight gain compared to the normal rats. The weight gain and feed efficiency ratios in 15 and 20% Wax gourd groups were higher than in STZ-control group. The plasma glucose levels were significantly lower in all Wax gourd groups than in STZ-control group. The plasma insulin levels in diabetic groups were not significantly different compared to the normal group, but the level of 20% Wax gourd group was higher than other diabetic groups. The experimental diabetic groups showed the higher levels of muscle glycogen compared to STZ-control group. The lower levels of plasma cholesterol were noticed in 20% Wax gourd group throughout the experimental period. The plasma level of triglyceride was elevated in STZ-diabetic control and the levels were slightly decreased in Wax gourd groups. Rats of 10% Wax gourd group showed the lower levels of plasma free fatty acids. It is suggested, from the results, that the possibility of therapeutic or preventive use of wax gourd to the diabetes mellitus.

• 대한치과기공학회지
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• 제26권1호
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• pp.105-114
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• 2004

This study obtained the following consequences, as a result of the comparative analysis for the castability depending on an angle of the sprue and wax pattern in case of manufacturing dental prostheses, for the castability depending on direction, and for the castablility of sprue, which attached the reserve to each different 3.5mm roll wax(sprue wax) and to 2.5mm sprue wax. 1. As a result of the comparative analysis for the castability depending on an angle of the sprue and wax pattern, the best castability was shown when the angle of the sprue and wax pattern is 180$^{\circ}\Delta$(straight line), and the lowest castability was shown in 45$^{\circ}\Delta$, which was curved most, and there was no statistical significance. 2. As a result of the comparative analysis for the castability of an angle depending on direction, the best castability was shown in the farthest side from the direction of centrifugal casting, and the lowest castability was shown in the same side as the direction of centrifugal casting, and there was no statistical significance. 3. Given comparing the castability depending on the pattern of sprue, the better castability was shown in 135$^{\circ}\Delta$ and 180$^{\circ}\Delta$ when using 3.5mm roll wax(sprue wax), compared to attaching the reserve to 2.5mm sprue wax.