• 한국재료학회:학술대회논문집
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• 한국재료학회 2009년도 춘계학술발표대회
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• pp.44.2-44.2
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• 2009

BCP powder was synthesized using microwave hydrothermal process with mixed calcium hydroxide and phosphoric acid. After using replica method, porous BCP scaffold was fabricated. PU (Poly Urethane) was used as the fugitive skeleton to fabricate the porous scaffold. BCP powder was mixed in PVB (Polyvinyl butyral) and ethanol solution and then applied to the PU foam by dip coating. After several times of coating and the subsequent oven drying the coated PU foam was burnt out at $750^{\circ}C$ at air to remove the PU. The resulting networked porous composites were sintered at $1250^{\circ}C$, $1300^{\circ}C$ and $1350^{\circ}C$ in microwave furnace for 30 minutes. Material properties of the porous bodies like compressive strength and porosity were investigated. Detailed microstructure of the BCP porous body was characterized by SEM and XRD and TEM techniques. In our experiments, the relationship between mechanical property and viscosity of powder, sintering temperature was investigated.

• 대한금속재료학회지
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• 제47권8호
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• pp.516-521
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• 2009

In this study we report a rapid synthesis of nanoporous organo-functional silica (OFS) with unimodal and bimodal pore structures encompassing pores ranging from meso-to macroscale. The problems of tediousness and high production cost in the conventional syntheses are overcome by co-condensation of an inexpensive inorganic precursor, sodium silicate with an organosilane containing trimethyl groups. The insitu covalent anchoring of the non-polar trimethyl groups to the inner pore walls prohibits irreversible shrinkage of the wet-gel during microwave drying at ambient pressure and thus larger size pores (from ca. 20 to ca. 100 nm) can be retained in the dried silica. The drying process of the silylated wet-gels at an ambient pressure can be greatly accelerated upon microwave exposure instead of drying in an oven or furnace. Using this approach, anoporous and superhydrophobic silicas showing a wide variation in texture and morphology can be readily synthesized in roughly two hours. The effects of various sol-gel parameters solely on the textural properties of the organo-functional silica (OFS) have been investigated and discussed.

• 한국생활과학회지
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• 제19권1호
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• pp.167-177
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• 2010

This study examined consumer perception and use on labeling of cooking utensils made of plastic and glass to get information about improving the labeling. The data were collected from 505 adults in Seoul, Busan, Daegu, Daejeon, Incheon, and Gwangju. The data were analyzed by SPSS Windows V.14.0. Frequencies, t tests, one-way analysis of variance, and Duncan's multiple range tests were carried out. Many respondents checked off 'precautions in use' more than any other notice when they purchased the cooking utensils made of plastic and glass. Respondents were dissatisfied with the letter size and intelligibility of foreign language on the labeling. Most respondents preferred 'tag' for most cooking utensils made of plastic and glass. In addition, on necessity of precautions for each category of plastic cooking utensils, frying pans, plastic baskets, plastic water buckets, plastic seasoning bottles, the frying pan showed the highest need for 'do not place close to the fire'. Plastic cups and plastic containers showed the highest in 'whether utensils could be used in the microwave oven and accompanying precautions', and plastic cutting board showed the highest in 'matters relating to washing before use.' In the case of cooking utensils made of glass, 'precaution on shock' was the highest for glass cups and mugs and 'whether utensils could be used in the microwave oven and accompanying precautions' was the highest for glass pans, dishes and containers.

• 분석과학
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• 제11권4호
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• pp.281-291
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• 1998

혈액과 소변중의 미량 Cu, Sn 및 Bi를 유도결합 플라스마 질량분석법으로 동시 분석하였다. 혈액시료 1 mL를 closed-vessel digestion system에 넣고 질산과 과산화수소수를 가한 후 microwave oven에서 8분 동안 전처리하였다. Amberlite IRC-718 수지를 정지상으로 사용한, 고체-액체추출법으로 Na, S, P 및 polyatomic species에 의한 매트릭스 방해를 제거하였다. 위 방법에 대한 검출한계를 구한 결과 Cu는 0.000375 ng/mL, Sn 은 0.000297 ng/mL, Bi는 0.000174 ng/mL 이었다. NIST SRM 955a 혈액시료에 표준용액을 첨가하여 구한 회수율은 Cu의 경우 99.1%, Sn은 102.5%, Bi는 98.4%이었다. 아울러 본 연구에서 조사한 최적기기 및 분석조건에서 실제 혈액과 소변시료의 분석을 시도하였다.

• 한국전자파학회논문지
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• 제16권12호
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• pp.1222-1228
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• 2005

본 논문은 MWO(Microwave Oven)의 동작 주파수로 사용되는 2.45 GHz 대역에서, 전자파 잔향실 내의 전기장특성 향상 및 시험 공간 확장에 관한 연구이다. 잔향실 내부에서의 전자기장 균일성을 확보하기 위하여, Sch-roeder 방식의 Quadratic Residue 확산기(diffuser)를 사용하였고, 전자기장 분포 해석을 위해 FDTD(Finite Difference Time Domain) 수치 해석 방식을 이용하였다. 잔향실 내부의 확산기는 도체로만 설계된 것(Type 1)과 유전체 및 도체를 같이 사용한 것(Type 2, 3)으로 설계하였다. 해석 결과 유전체를 사용한 확산기는, 유전체 없는 확산기의 전기장 특성을 유지하면서 확산기의 물리적 크기를 줄일 수 있었고, 특히 Type 3 확산기에서는 동일한 물리적 공간에 더 많은 주기의 확산기를 설계할 수 있어, 시험 공간 확장, 잔향실의 편파 특성, 편차 및 공차등의 성능이 가장 좋은 것을 확인하였다.

• 한국식품과학회지
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• 제18권4호
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• pp.319-324
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• 1986

가수량율 1.3배 1.5배 1.7배로 하여 취반후 실온에서 1시간 식혀서 관능검사를 실시한 경우 부착성을 제외한 모든 특성에서 유의적인 차이를 나타내었다. 효소소화법에 의한 호화도의 측정시 압력솥 취반미가 전기솥 취만미보다 높은 호화도를 나타내었다. 하루동안냉장보관하였다가 전자오븐으로 재가열한 시료와 신선시료에 대한 관능적인 특성은 견고성을 제외한 모든 특성에서 유의적인 차이를 나타내었으며, 동일기구 내에서의 차이는 적었으나 두 취반기구 간의 차이는 현저하였다. 위와 같은 결과에서 본 연구의 조건 하에서는 동일한 쌀이라도 취반미의 특성이 현저히 달라진다고 할수 있다. 또한 냉장시료를 전자오븐으로 재가열한 시료는 신선시료에 비해 차이가 크지 않아서 복원럭이 크다는 것을 알 수 있다.

• 한국축산식품학회지
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• 제36권1호
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• pp.23-28
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• 2016

This study investigates the effect of cooking, storage, and reheating conditions on the formation of cholesterol oxidation products (COPs) in pork loin. Samples of pork loin procured 24 h postmortem were initially processed and assessed for total fat and cholesterol content. The cooking methods evaluated were pan roasting, steaming, oven grilling, and microwaving. Cooked pork loin samples were stored at 4℃ and reheated after 3 and 6 d of storage using the original method of preparation or alternately, microwaving. Fat content increased significantly with cooking as a result of the loss in moisture but cholesterol content remained unchanged. Pan roasting and microwave cooking caused a significantly higher production of COPs, as with the process of reheating using microwave, pan roasting, and oven grilling methods. The major COPs found in pork loin were cholestanetriol, 20-hydroxycholesterol, and 25-hydroxycholesterol, whose concentrations varied according to the different cooking and reheating methods used. Moreover, the aerobic storage of cooked pork loin under a refrigerated condition also increased the formation of cholesterol oxides on reheating.

• 한국식품조리과학회지
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• 제2권2호
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• pp.21-31
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• 1986

Here is a research on hospital foodservice system, when korea traditional food of pyeon yuk and bin dae deok were used by ready-prepared foodservice system, it was estimated the preservations of microbiological quality and sensory quality. All data collection was replicated three times. The results were as following; 1. In time and temperature data, two menu items were needed internal temperature below $7^{\circ}C$ in a cooling stage, and in the case of cook/chill storage, the days were shortened within weeks, and the holding time must be possiblely minimized. Finally foods were served sanitary. 2. In view of microbiological safety, in the case of cook/chill storage as $0{\sim}4^{\circ}C$ the days must be shortened within 2 weeks and its was possible to store until 6 weeks in $-20{\sim}-23.3^{\circ}C$. So to preserve pre-cooked food longly, it was effective to freeze them quickly by using vacuum package and to reheat them by a microwave oven before serving and to serve lastly in microbiological quality. 3. Hospital ready-prepared foodservice system with food storage in plastic bags, biochemical test of C. Perfingens C. botulinum and Salmonella were not detected. 4. By using of a microwave oven, it had effects of thawing, reheating and sterilizing of chilled and frozen foods in a short time. 5. Sensory evaluations were made by a 10-member panel using five scoring tests. Because sensory of quality was lowered in the case of chilled storage, it was possible to serve foods within 2 weeks. Texture and aroma were preserved by cook/frozen system and usually there was no significance from 4 weeks until 6 weeks, but considering of the objects, it was good to store until 4 weeks in sensory quality.

• 한국식품과학회지
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• 제32권2호
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• pp.335-340
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• 2000

연시 및 puree의 냉동저장중 품질변화와 puree의 갈변방지를 위한 ascorbic acid첨가 및 데치기 처리효과에 관한 결과는 다음과 같았다. 총 carotenoid, 환원당 및 가용성 고형분 함량은 저장 중 별다른 변화를 보이지 않았으나, ascorbic acid함량은 저장기간이 경과함에 따라 지속적으로 감소하였다. 청도반시의 경우 저장 중 저온 및 microwave oven을 사용해 해동할 경우, 해동 방법에 따른 품질 특성의 차이를 보이지 않았다. 한편, puree의 점도는 해동 후 급격히 저하되는 경향을 보였으며, Hunter L, a, b값은 지속적으로 감소하여 모든 시료에서 갈변되는 경향을 보였으나, ascorbic acid를 첨가함으로써 갈변현상이 지연되었다. 반면, puree를 데치기 하였을 때 변색과 gel화에 따른 급격한 점도의 증가를 유발함에 따라 갈변 억제 수단으로써 실용성이 없는 것으로 판단된다.

• 한국식품과학회지
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• 제31권6호
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• pp.1583-1588
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• 1999

마늘의 향미를 조절하기 위하여 박피하지 않은 마늘쪽을 $60^{\circ}C{\sim}90^{\circ}C$의 범위에서 30분간 예열처리한 경우와 전자레인지로 10초간 가열한 경우에 마늘의 향미성분변화를 조사한 결과는 다음과 같다. 마늘의 향기성분은 예열처리 온도가 상승함에 따라 감소하였고, $70^{\circ}C,\;80^{\circ}C$ 및 $90^{\circ}C$에서 30분간 예열처리하면 대조구에 비하여 각각 20%, 31% 및 49% 감소하였다. 전자레인지로 10초간 가열한 경우에는 열풍건조기에서 $70^{\circ}C{\sim}80^{\circ}C$에서 가열한 것과 유사한 경향을 보였다. 열풍건조기로 예열처리하면 glucose, fructose 및 fructooligosaccharide가 감소하였으며, 이런 감소는 온도가 높을수록 컸으며 fructooligosaccharide 보다는 단당류인 glucose와 fructose에서 더욱 컸다. 전자레인지로 가열처리한 경우에는 열풍건조기로 예열처리한 경우에 비하여 유리당의 변화가 현저히 적었다. Alliin의 분해산물로 알려진 pyruvic acid는 예열처리 온도가 증가할수록 감소하는 경향을 나타내었고, 그 밖의 유기산은 유의적 변화가 없었다. 마늘의 주요 아미노산인 arginine은 열풍에 의한 예열처리시 감소하였으나 전자레인지로 가열한 경우에는 감소하지 않았고, glutamic acid와 tyrosine은 모든 처리구에서 감소하였다.