• 대한의생명과학회지
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• 제25권2호
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• pp.170-176
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• 2019

The objective of this study was to evaluate the characteristics of the mixtures of choline alphoscerate (alpha-glycerylphosphorylcholine, alpha-GPC), in the liquid form, and sucrose ester, which formed a solid composite. The choline alphoscerate solid composites were prepared using different ratios of sucrose ester, and different preparation methods, such as air drying and rotary evaporation, were compared for their preparation efficacy. We examined the characteristics of the solid composites by using scanning electron microscopy (SEM), angle of repose, and moisture content. The ideal mixing ratio of choline alphoscerate and sucrose ester was determined as 1:3 and air drying was found to be more suitable for the preparation of solid composites than rotary evaporation. SEM measurements of the degree of dispersion and the size of particles indicated that a high-temperature air method was more suitable. These results demonstrated the successful preparation of choline alphoscerate solid composites that have potential for industrial use.

• 한국해양환경ㆍ에너지학회지
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• 제15권3호
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• pp.238-246
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• 2012

해양으로 유출된 유류는 다양한 풍화과정을 통해 환경에서 제거되며, 증발이 유출사고 초기에 가장 우세한 풍화과정이다. 본 연구에서는 허베이스피리트호 사고유 중 이란산 원유를 대상으로 실험실에서 표준화된 증발실험을 실시하여 시간에 따른 물리화학적 변화를 관찰하였다. 증발과정에 영향을 미치는 유막두께, 풍속 등의 변수를 제어하여 48시간까지 노출한 결과 $29.3{\pm}0.4%$의 재현성 있는 결과를 산출하였다(n=40, p<0.001). 미국해양대기청의 풍화모델인 ADIOS2를 이용하여 환경조건에서 증발을 시뮬레이션한 결과 29%의 증발율을 구할 수 있었으며, 본 실험과 일치하는 결과를 확인하였다. 증발율에 따른 원유의 조성변화를 분석한 결과 저분자량의 알칸과 PAHs가 제거되었으나, 바이오마커 화합물은 증발에 의한 영향을 받지 않는 보전적인 특성을 나타냈다. 바이오마커 중 $17{\alpha}(H)$, $21{\beta}(H)$-hopane을 이용한 풍화율 계산값은 48시간 최종 값이 24.4%로 물리적인 증발에 따른 양적변화와 유사한 결과를 보였다. 호판을 이용한 풍화율 계산값 비교결과 사고 초기 현장 표착유(1단계 풍화 28.9%)와 메소코즘 풍화 실험 5일차(26.5%)까지는 풍화과정이 주로 증발에 의한 것으로 확인되었다.

• 한국연소학회지
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• 제20권2호
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• pp.1-13
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• 2015

Drying, which is the oldest and most energy-intensive process, is an essential process for treatment of solid product. The specific procedure to design and evaluate the dryers, which are a rotary kiln dryer and a flash dryer, in case of drying the high-moisture coal was described. From determination of size to the heat and mass balance in one-dimensional model were conducted to evaluate the performance of dryers. Heat consumption, inlet gas temperature and size of the dryers were compared between a rotary kiln dryer and a flash dryer. Further considerations to evaluate the reactor elaborately were also discussed. Performance simulation of dryers along with the design procedure described here will provide helpful basis for understanding the concept of reactor design.

• Macromolecular Research
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• 제11권3호
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• pp.183-188
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• 2003

The controlled delivery of anticancer agents using biodegradable polymeric implant has been developed to solve the problem of penetration of blood brain barrier and severe systemic toxicity. This study was performed to prepare 5-FU-loaded poly (L-lactide-co-glycolide) (PLGA) wafer fabricated microparticles prepared by two different method and to evaluate their release profile for the application of the treatment of brain tumor. 5-FU-loaded PLGA microparticles were characterized by scanning electron microscopy (SEM), powder X-ray diffraction (XRD), and differential scanning calorimetry (DSC). SEM observation of the 5-FU-loaded PLGA microparticles prepared by rotary solvent evaporation method showed that 5-FU was almost surrounded by PLGA and significant reduction of crystallinity of 5-FU was confirmed by XRD. In case of release profile of 5-FU from 5-FU-loaded PLGA wafer fabricated microparticles prepared by mechanical mixing, the release profile of 5-FU followed near first order release kinetics. In contrast to the above result, release profile of 5-FU from 5-FU-loaded PLGA wafer fabricated microparticles prepared by rotary solvent evaporation method followed near zero order release kinetics. These results indicate that preparation method of the 5-FU-loaded PLGA microparticles to fabricate into wafers was contributed to drug release profile.

• Korean Chemical Engineering Research
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• 제60권2호
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• pp.237-242
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• 2022

본 연구에서는 정제된(+)-dihydromyricetin로부터 잔류 용매를 효과적으로 제거할 수 있는 건조 방법을 개발하였다. 에탄올 전 처리를 통한 회전 증발(rotary evaporation)에 의해 잔류 아세톤 농도를 ICH 규정치(5,000 ppm) 이하로 효율적으로 제거하였다. 또한 잔류 에탄올 역시 물 첨가를 통한 회전 증발로 ICH 규정치(5,000 ppm)를 충족시켰으며 잔류 수분 함량은 4% 이내였다. 모든 건조 온도(35, 45, 55 ℃)에서 잔류 용매는 건조 초기에 급격히 제거되었으며 건조 효율은 건조 온도가 높을수록 증가하였다. 건조 메커니즘 조사 결과, 에탄올 전 처리에 의한 잔류 용매 제거는 아세톤-에탄올 혼합물의 높은 증기압과 아세톤-에탄올 간의 수소 결합과 연관됨을 알 수 있었다.

• Korean Chemical Engineering Research
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• 제55권6호
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• pp.807-815
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• 2017

본 연구에서는 회전증발에서 건조 온도에 따른 파클리탁셀의 잔류 펜탄 제거 효율에 대해 조사하였으며 건조 공정에 대한 동역학 및 열역학적 해석을 수행하였다. 모든 온도(25, 30, 35, 40, $45^{\circ}C$)에서 건조 초기에 많은 양의 잔류용매가 제거되었으며 건조 온도가 증가할수록 건조 효율은 증가하였다. 동역학적 해석을 위해 실험데이터 값을 다섯 종류의 건조 모델식(Newton, Page, Modified Page, Henderson and Pabis, Geometric)에 적용하였으며, 이 중 Henderson and Pabis 모델이 큰 결정계수 값과 작은 평균평방근편차 RMSD 값을 가져 가장 적합함을 확인하였다. 또한 열역학적 해석을 수행한 결과, 회전증발에서의 활성화 에너지 $E_a$는 4.9815 kJ/mol이었으며, 표준 Gibbs 자유에너지 변화(${\Delta}G^0$)는 음수 값인 반면 표준 엔탈피 변화(${\Delta}H^0$)와 표준 엔트로피 변화(${\Delta}S^0$)는 양수 값을 나타내어 건조 공정이 자발적 흡열반응이며 비가역적으로 수행됨을 알 수 있었다.

• 국제초고층학회논문집
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• 제12권4호
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• pp.335-341
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• 2023

This study proposes a novel rotary direct evaporative cooler and investigates the potential of a moisture-wicking fabric as a cooling pad for the proposed evaporative cooler. The rotary direct evaporative cooler rotates the cooling pad to reduce the water and energy consumption of the pump compared to those of existing direct evaporative coolers. A moisture-wicking fabric is considered as the material of the cooling pad, because of its high moisture-wicking property, enhancing water evaporation. Experiments are performed under various inlet air conditions while measuring the air temperature, relative humidity, air velocity, and differential pressure. The evaporative cooling efficiency and impacts of the inlet air temperature and air velocity on the cooling performance are also evaluated. The results demonstrate the potential of the moisture-wicking fabric as cooling pad of direct evaporative cooler.

• 한국정밀공학회지
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• 제16권3호통권96호
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• pp.62-71
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• 1999

Integrating micro-machined sensors and actuators on the conventional devices with the copper power lines was incompatible to fabricate the mass produced micro electromechanical system (MEMS) devices. To achieve the compatibility of the wiring method between MEMS parts and devices, we developed the three-dimensional sputter-evaporation system that coats micropatterned thin copper films on the surface of the MEMS element. The system consists of a process chamber, two branch chambers, the substrate holder, and a linear-rotary motion feedthrough. Thin copper film was sputtered and evaporated on the biocompatible polymer, Pellethane$^{circed{R}}$ and silicone, catheter that is 2 mm in diameter and 700 mm in length. The metal film coating technique with three-dimensional thin film sputter-evaporation system was developed to apply the power and signal lines on the micro active endoscope. In this paper, we developed the three-dimensional metal film sputter-evaporation system operated on the low temperature for the biopolymeric substrates used in the medical MEMS devices.

• Preventive Nutrition and Food Science
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• 제8권3호
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• pp.225-229
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• 2003

Clarified apple, carrot and orange juices were prepared using ultrafiltration and their single and blend juices were further concentrated using ultrafiltration, freeze-drying, and rotary evaporation. Effect of concentration methods on the quality of concentrated single juices and juice blends was investigated. Turbidity values of samples concentrated by evaporation were significantly higher than those prepared by ultrafiltration and vacuum freezing regardless of juice source (i.e., apple, orange or carrot) or blending (p<0.05). The highest soluble solids contents were obtained for the samples concentrated by evaporation process. Concentrated apple juice contained significantly higher amount of vitamin C and soluble solids than concentrated orange and carrot juices regardless of concentration methods (p<0.05). For blended samples, no direct relationships between blend ratio and total amount of vitamin C were found; however, samples contained more apple juice showed the highest value of soluble solids regardless of concentration methods.

• 한국정밀공학회:학술대회논문집
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• 한국정밀공학회 1997년도 춘계학술대회 논문집
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• pp.362-365
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• 1997

In the field of Micro-Mechanics, it has been known diffcult to integrate the micro-machine with sensor and source line for the conventional copper line cnanot be used in compact and small size. We developed a system to make thethin copper film as a connect line on the poyurethane pipe (2mm in diameter) by the evaporation technique. This system consists of an evaporation chamber two long branches, substrate hoider and a Linear-Rotary motion feed feedthrough. The results showed that thin copper film coated polyurethanc pipe could be applied th the small medical devices such as the micro active endoscope.