세 개의 히드록실기를 가진 양이온 계면활성제 합성 및 계면 특성에 관한 연구

이병민 ( Byung Min Lee ),김지현 ( Ji Hyun Kim ),김승수 ( Sung Soo Kim ),임종주 ( Jong Choo Lim ) 한국공업화학회 2012 공업화학 Vol.23 No.5

본 연구에서는 도데실 글리시딜 에테르와 아미노에탄올을 반응시킨 후 디메틸 설페이트로 4급화시켜 분자 내에 2개의 라우릴기, 3개의 히드록실기를 가진 양이온 계면활성제 BHMAS (N, N-bis-(3`-n-dodecyloxy-2`-hydroxypropyl)-N-methyl- 2-hydroxyethylammonium methyl sulfate)를 합성하였고, 생성물의 분자구조는 1 H-NMR, FT-IR 등의 기기분석을 통하여 확인하였다. 합성한 계면활성제의 CMC (critical micelle concentration)는 9.12 × 10 -4 mol/L이며, CMC에서의 표면장력은 28.71mN/m이었다. Maximum bubble pressure tensiometer를 사용하여 동적 표면장력을 측정한 결과, 공기와 수용액의 계면이 계면활성제 단분자에 의하여 포화되는 데 비교적 오랜 시간이 소요되었다. 1 wt% 계면활성제 수용액과 n-decane 사이의 계면장력은 0.045mN/m이며, 평형에 도달하는 데 약 5 min의 시간이 소요되었다. 합성된 계면활성제의 흡착 특성이 매우 우수하였으며, 합성한 양이온 계면활성제가 섬유표면에 효과적으로 흡착되어 유연효과를 나타낼 수 있음을 확인하였다. In this study, a cationic surfactant BHMAS (N,N-bis-(3`-n-dodecyloxy-2`-hydroxypropyl)-N-methyl-2-hydroxyethylammonium methyl sulfate) having two lauryl and three hydroxyl groups was synthesized by the reaction of n-dodecyl glycidyl ether and 2-aminoethanol followed by the quarternization with dimethyl sulfate. The structure of the product was elucidated by 1 H-NMR and FT-IR. The CMC (critical micelle concentration) and surface tension of BHMAS at CMC condition were found to be 9.12 × 10 -4mol/L and 28.71mN/m respectively. Dynamic surface tension measurements using a maximum bubble pressure tensiometer indicated that a relatively long time was required to saturate the interface between air and aqueous surfactant solution. The interfacial tension measured between 1 wt% surfactant solution and n-decane reached an equilibrium value of 0.045mN/m in 5 min. The adsorption capacity of the synthesized surfactant was observed to be excellent, which suggests that the surfactant can be used as a softening agent during a laundry process.

친환경 세척제의 처리 방법을 달리하여 착즙한 당근 주스의 미생물 안전성 및 품질

임상욱(Sang-Wook Lim),최다정(Da-Jeong Choe),강민정(Min-Jung Kang),김종현(Jong-Hyun Kim),김묘정(Myo-Jeong Kim),김민주(Min-Ju Kim) 한국식품영양과학회 2017 한국식품영양과학회지 Vol.46 No.10

본 연구에서는 당근의 세척에 사용되는 친환경 세척제의 초기 미생물 제어 효과를 향상시키기 위해 탄산수소나트륨과 구연산의 단독 및 병합 처리 조건을 설정하였으며 저장 중 당근 주스의 미생물 수 및 품질 특성 변화를 분석하였다. 친환경 세척제의 단독 처리 방법으로는 0.5, 1, 2% 탄산나트륨수와 0.2, 0.5, 1% 구연산수를 적용하였고, 살균 효과를 비교하기 위해 무처리구, 수돗물 처리구, 50 ppm 차아염소산나트륨 처리구를 사용하였다. 당근의 세척을 위한 병합처리 방법으로는 단독 처리에서 우수한 살균 효과를 나타낸 1% 탄산수소나트륨수와 1% 구연산수를 이용하였고, 1% 탄산수소나트륨수 처리 후 1% 구연산수로 처리하는 단계적 병합 처리구가 가장 우수한 살균 효과를 나타내었다. 1% 탄산수소나트륨수와 1% 구연산수의 단계적 병합 처리구는 무처리구에 비해 일반 세균수 1.87 log CFU/mL, 대장균군 1.56 log CFU/mL를 감소시켰고, 50 ppm 차아염소산수에 비해서도 일반 세균수 1.07 log CFU/mL, 대장균군 0.22 log CFU/mL의 미생물 감균효과를 나타냈다. 1% 탄산수소나트륨수 처리 후 1% 구연산수의 단계적 병합 처리구를 4°C에서 7일 동안 저장한 결과 수돗물, 50 ppm 차아염소산수나 혼합 병합 처리구, 1% 구연산수 처리 후 1% 탄산수소나트륨 처리구에 비해 미생물 제어 효과가 확실하게 나타났지만, pH, 당도, 산도, 색도에는 유의적인 차이가 나타나지 않았다. 본 연구 결과 1% 탄산수소나트륨과 1% 구연산의 단계적 병합 처리는 당근 세척 시 초기 미생물 제어와 품질 유지에 있어 효과적인 살균처리 방법으로 비가열 당근 주스의 유통기간 동안 미생물 안전기준에 부합하며 주스의 품질을 유지할 수 있는 바람직한 세척방법으로 판단된다. The aim of this study was to evaluate the microbial inhibitory activity and physicochemical quality of fresh carrot juice prepared with different environmentally-friendly washing methods during low temperature storage. Individual and combined treatments with sodium bicarbonate (baking soda, NaHCO₃) and citric acid were applied to carrots for 10 min. Tap water and 50 ppm of sodium hypochlorite (NaOCl) were used as the control. Combined treatment of 1% NaHCO₃ and 1% citric acid significantly reduced total aerobic counts and coliforms. In addition, combined treatment of 1% NaHCO₃ and 1% citric acid inhibited microbial growth for 7 days at 4°C and 10°C in a shelf-life study. There were no significant differences among the sanitizers in terms of °Brix, acidity, pH, and color. Changes in physicochemical quality were not significantly different by sanitizer but were affected by storage temperature. These results indicate that washing with combined treatment of 1% NaHCO₃ and 1% citric acid is an effective method to inhibit the microbial population and maintain physicochemical quality. Therefore, combined treatment of 1% NaHCO₃ and 1% citric acid can be effectively used to sanitize and prepare carrot juice without affecting other properties.

온풍 조건에서 수분 탈락 정도에 따른 피부 분류 및 개선 방안에 대한 연구

권오선 ( Oh Sun Kwon ),강현종 ( Hyun Jong Kang ),한승민 ( Seung Min Han ),윤지선 ( Ji S Eon Yoon ),조웅희 ( Woong Hee Cho ),오주영 ( Joo Young Oh ),임준만 ( Jun Man Lim ),송영숙 ( Young Sook Song ),박선규 ( Sun Gyoo Park ) 대한화장품학회 2020 대한화장품학회지 Vol.46 No.2

피부를 탄력있고 부드럽게 하는 역할은 각질층에 존재하는 수분량에 의해 좌우된다. 피부 수분량은 냉온풍, 건조환경 등 다양한 환경 변화에 의해 영향을 받음이 알려져 있으나, 개인 피부 차이에 따른 피부수분량 변화와 회복 정도에 대해서는 많은 연구가 이루어 지지 않은 실정이다. 본 연구에서는 온풍 조건하에서 피시험자들의 피부 수분 탈락 및 회복 정도를 비교 평가하여 새로운 피부 타입을 제시하고, 온풍 조건에서 저하되는 피부 수분량을 개선 시켜주는 효능 물질을 개발하고자 하였다. 온풍 환경 조성을 위해, 건강한 피험자(남: 10 명, 여: 39 명, 25 세 - 63 세)의 전완부에 온풍(30 cm, 40 ℃, 6 m/s)을 30 min 간 피부에 노출시켜, 피부 수분량의 변화를 평가하였다. 26명(남: 4 명, 여: 22 명, 평균 연령: 42.7 ± 9.4)이 온풍 노출전에 비하여 온풍 노출 후 수분량이 유의하게 감소하며, 노출 후 30 min이 지나도 회복이 되지 않았다. 온풍노출 후 수분량이 떨어지는 피험자(여: 10 명)를 대상으로 보수력이 높은 크림을 3 주간 전완부에 적용한 이후 동일 온풍 조건하에서 피부 수분량을 측정한 결과, 노출 30 min 후 피부 수분량이 온풍 노출 전 수준으로 회복됨을 확인하였다. 본 연구를 통하여 피부는 건조 조건에서 쉽게 수분을 잃어버리는 피부(탈수형 피부)가 존재하는 것을 확인하였다. 이는 앞으로 화장품 개발을 보습 기능뿐만 아니라, 이러한 환경변화에 따른 피부수분이 쉽게 빠져나가는 피부(탈수형 피부)의 특성에 맞는 제품의 효능 개발이 필요함을 보여준다. Elasticity and softness of the skin depend on the level of moisture present in the stratum corneum, which is known to be affected by various environmental changes, such as cold and hot winds and dry environments. However, not many studies have been conducted on changes in skin moisture and the degree of recovery due to individual skin differences. In the present study, we aimed to investigate the effect of warm air heating on skin hydration levels and develop moisturizing formulas to improve lowered skin hydration levels. In order to deliver warm air heating condition, heating dryer (40 ℃, 6 m/s, 30 cm apart from forearm) was applied into inner forearm of healthy subjects (male: 10, female: 39, age: 25 - 63) Among 49 subjects, 26 subjects showed significantly lowered skin hydration levels until 30 min after warm air heating exposure (lowered group). In addition, moisturizing cream with high water holding capacity was applied to forearm of 10 subjects in lowered group for 3 weeks and skin hydration levels after warm air heating were significantly improved at the levels of before application of warm air heating. From this study, we found out that there is a skin type that skin hydration levels are significantly decreased under warm air heating condition (dehydrated skin) and this dehydrated skin can be improved by moisturizing formulas with high water holding capacity.

복식전자궁적출술 후 경막외 통증 관리시 0.1% Bupivacaine/Morphine과 0.1% Ropivacaine/Morphine의 비교

임일환,문철준,반종석,민병우 대한마취과학회 2002 Korean Journal of Anesthesiology Vol.43 No.5

Background: Local anesthetics combined with an opioid are frequently used as a postoperative epidural analgesia, to minimize individual doses and to reduce unwanted side effects. The aims of this study were to compare analgesic effectiveness, occurrence of motor block and other side effects of a 48 hr postoperative continuous epidural infusion of 0.1% bupivacaine/morphine or 0.1% repivacaine/morphine. Methods: Forty female patients scheduled for an elective total abdominal hysterectomy under general anesthesia were randomized in a double-blind fashion to receive either 0.1% bupivacaine with 0.02 mg/ml morphine or 0.1% ropivacaine with 0.02 mg/ml morphine using a continuous epidural analgesia pump at a rate of 4 ml/hr during the postoperative 48 hours. After toe operation, we assessed the blood pressure, heart rate, visual analog scale (VAS), side effects, additional analgesic requirement and time to ambulation for 48 hours in 12-hour intervals. Results: There were no significant differences in VAS on rest and cough between the groups, but VAS on deep breathing and position change were significantly lower in the bupivacaine group compared to the ropivacaine group. Side effects were similar in both groups except paresthesia. Time to ambulation was earlier in the ropivacaine troup compared to the bupivacaine group. Conclusions: Both the postoperative continuous epidural infusion of 0.1% bupivacaine with morphine and 0.1% ropivacaine with morphine provided similar pain relief and side effects. However, earlier recovery of ambulation in patients receiving ropivacaine/morphine will improve outcome after abdominal surgery. (Korean J Anesthesiol 2002; 43: 633~639)

하지수술시 Fentanyl과 병용한 0.75% 등비중 Ropivacaine을 이용한 척추마취

임일환,이상곤,반종석,민병우 대한마취과학회 2002 Korean Journal of Anesthesiology Vol.43 No.5

Background: Opioids and local anesthetics administered together intrathecally have a potent synergistic analgesic effect and less hypotention using a minidose of local anesthetic. This study was designed to investigate the safety and efficacy of two doses of intrathecal isobaric ropivacaine/fentanyl in patients undergoing an operation of the lower extremities. Methods: Thirty patients undergoing an elective orthopedic surgical operation of the lower extremities were randomly assigned to two groups for spinal anesthesia. Patients in group Ⅰ (n = 15) received 0.75% ropivacaine 14 mg/fentanyl 20㎍, and patients in group Ⅱ (n = 15) received 0.75% ropivacaine 16 mg/fentanyl 20㎍. After spinal anesthesia, we measured the time to T10, peak dermatomal level, time to peak sensory level, time to maximum motor blockade, duration of complete motor block and duration of complete sensory block using the pin prick test and Bromage motor scale. Also circulatory variables were monitored every 5 min and side effects were measured for 3 day after spinal anesthesia. Results: There were no significant differences between the groups in time to T10, peak dermatomal level, time to peak sensory level, time to maximum motor blockade and duration of complete motor block, but duration of complete sensory block was significantly longer in the 0.75% ropivacaine 16 mg/fentanyl 20㎍ group than the 0.75% ropivacaine 14 mg/fentanyl 20㎍ group. Conclusions: Intrathecal 0.75% ropivacaine 14 mg/fentanyl and 0.75% ropivacaine 16 mg/fentanyl were equally suitable for a lower extremity operation. (Korean J Anerthesiol 2002; 43: 600~605)

유럽통합의 심화와 대외관계의 변화

임문영,이종광,김승민,류두하 계명대학교 국제학연구소 1996 국제학논총 Vol.1 No.-

통합 건설현장 모니터링 시스템의 적용에 관한 연구

임종철,이원민,김창성,여운광 명지대학교 산업기술연구소 2008 産業技術硏究所論文集 Vol.27 No.-

The recent heavy downpours, tsunami, and flooding in Korea have cause devastating casualties and astronomical economic losses. In addition, construction sites are exposed to the dangers of structural collapses and damages due to these natural disasters. Studies for monitoring the dangers of construction sites must focus on reducing the amount of casualties and improve prevention measures as their main purpose. The monitoring svstem developed in this study provides both vertical inclinometer and rainfall monitoring with credible accuracy. This system provides more efficient and safe construction site management and preventative measures possible.

유화중합을 이용한 4원공중합 바인더의 제조와 특성

임종민,하선희,임재길,설수덕 東亞大學校 大學院 2004 大學院論文集 Vol.29 No.-

Styrene-Acrylonitrile-Ethylacrylate-N-Methyloacryamide Prepared by emulsion polymerization has broad applications for additives such as paint binder, adhesive for wood and paper due to its low glass transition temperature which help to plasticize substrate resins. Since emulsion polymerization has disadvantage that surfactant and ionic initiator degrade properties of the product polymer, Poly(St-EA-AN-NMA) was synthesized using ammonium persulfate(APS) as catalyst and sodium lauryl sulfate(SLS) as emulsion to prevent the degradation. The copolymer binder product was internally plasticized and has enhanced colloid stability, adhesion, tensile strength and elongation. During binder emulsion polymerization, no coagulation and complete conversion occur with the reactant mixture of 3.34wt%/monomer ammonium persulfate, 2.33wt%/monomer sodium lauryl sulfate, and the balanced monomer that the weight ratio of Styrene, Ethylacrylate, Acrylonitrile are 47wt%/monomer, 32wt%/monomer, 6.4wt%/monomer. The activation energies for 37, 42, 47, 52% Styrene content were checked as 28.1~36kcal/mol by Kissinger's method. Actually, reasonable solid content could be considered as 56% because of activation energy and adhesive characteristics.

피치제어를 이용한 풍력발전시스템의 출력제어

임종환,최민호,허종철,김건훈 濟州大學校 産業技術硏究所 2000 산업기술연구소논문집 Vol.11 No.1

This paper derives a modeling of a wind turbine and generator. and presents a power control algorithm for a full pitch-controlled wind turbine system. The design of a controller. in general. is performed by linearizing the torque in the vicinity of a operating point assuming the tip speed ratio is constant. For power control. however. the tip speed ratio is no longer a constant. In this study. a reference pitch model is derived in terms of a wind speed. angular velocity. and pitch angle. which makes it possible to design a controller without linearizing the non-linear torque model of the blade. The validity of the algorithm is demonstrated with the results produced through sets of simulation.

피치제어를 이용한 풍력발전시스템의 출력제어

임종환,최민호,허종철,김건훈 제주대학교 산업기술연구소 2000 尖端技術硏究所論文集 Vol.11 No.2

This paper derives a modeling of a wind turbine and generator, and presents a power control algorithm for a full pitch-controlled wind turbine system. The design of a controller, in general, is Performed by linearizing the torque in the vicinity of a operating point assuming the tip speed ratio is constant. For power control, however, the tip speed ratio is no longer a constant. In this study, a reference pitch model is derived in terms of a wind speed, angular velocity, and pitch angle, which makes it possible to design a controller without linearizing the non-linear torque model of the blade. The validity of the algorithm is demonstrated with the results produced through sets of simulation.