• 한국식품조리과학회지
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• 제10권4호
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• pp.381-385
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• 1994

The dietary fiber contents of soybean sprout and spinach were changed by heat treatment. Before heat treatment, soybean sprout and spinach had larger amount of insoluble dietary fiber than soluble, and similar proportions of insoluble v/s soluble dietary fibers. After heat treatment, the value of insoluble dietary fiber of soybean sprout and spinach was increased significantly, except for microwave heating short time treatment. It is believed that the increment of insoluble dietary fiber is due to Maillard reaction products and resistant starch after heat treatment. The change of soluble dietary fiber contents of soybean sprout and spinach were not consistent in heat treatment. It is supposed that some soluble dietary fiber was destroyed by heat treatment, and some insoluble dietary fiber was hydrolysed or destroyed to be soluble. Total dietary fiber of soybean sprout and spinach was significantly incereased by all heat treatment, except for microwave heating short time of spinach.

• 한국결정성장학회지
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• 제10권1호
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• pp.66-72
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• 2000

재래식 및 마이크로파 가열법으로 열처리된 $Li_2O_3-SiO_2$계 글라스의 핵 생성 및 결정화 거동을 열분석법(DTA), X-선 회절(XRD), 광학 현미경(OM) 및 전기 전도도의 측정으로 비교 조사하였다. 재래식 및 마이크로피로 열처리된 시료들의 조핵 온도와 최대 핵 생성 온도는 동일하게 각각 460~$500^{\circ}C$와 $580^{\circ}C$이었다. 한편, 재래식에 비하여 마이크로파로 열처리된 시료에서는 부피 핵 생성이 일어나려는 경향이 컸다. 재래식 및 마이크로파로 열처리된 시편들에서 결정의 성장 속도는 결정화 열처리 온도에 비례하여 증가하였지만, 마이크로파 열처리의 경우는 부피 핵 생성 경향 및 물질 확산 효과의 증대에 기인하여 결정 성장을 재래식 보다 빠르게 진행되었다. 재래식 및 마이크로파로 열처리된 시편들의 전기 전도도 값은 각각 1.337~2.299와 0.281~$0.911{\times}10^{-7}\Omega {\textrm}{cm}^{-1}$이었다.

• 한국세라믹학회지
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• 제54권6호
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• pp.499-505
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• 2017

Flexible silicon carbide fibrous mats were fabricated by a combination of electrospinning and a polymer-derived ceramics route. Polycarbosilane was used as a solute with various solvent mixtures, such as toluene and dimethylformamide. The electrospun PCS fibrous mats were cured under a halogen vapor atmosphere and heat treated at $1300^{\circ}C$. The structure, fiber morphology, thermal behavior, and crystallization of the fabricated SiC fibrous mats were analyzed via scanning electron microscopy (SEM), X-ray diffraction (XRD), and thermal imaging. The prepared SiC fibrous mats were composed of randomly distributed fibers approximately $3{\mu}m$ in diameter. The heat radiation of the SiC fiber mats reached $1600^{\circ}C$ under microwave radiation at a frequency of 2.45 GHz.

• 대한치과보철학회지
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• 제34권4호
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• pp.816-822
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• 1996

The purpose of this study was to determine whether there was any difference in the mean porosity of denture base resin cured by microwave energy, when the liquid monomers of denture resin(K-33 : methyl methacrylate for conventional water bath curing or Acron MC : special monomer for microwave curing) and/or the thicknesses of denture base($5{\times}10{\times}60mm\;or\;10{\times}10{\times}60mm$) were varied. The mean porosities of k-33 specimens cured in water bath with two different thicknesses were used as control. The results were as follows : 1. Regardless of specimen thickness, Acron MC cured by microwave energy showed the least mean porosity, followed by K-33 cured by water bath heat, and K-33 cured by microwave energy showed the highest level of mean porosity(P<0.05). 2. In both K-33 and Acron MC cured by microwave energy the mean porosities of 5mm thickness groups were lower than those of 10mm thickness groups(P<0.05). But no significant difference was found in mean porosity between 5mm thickness and 10mm thickness of water bath heat cured groups made of K-33(P>0.05).

• 한국고분자학회:학술대회논문집
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• 한국고분자학회 2006년도 IUPAC International Symposium on Advanced Polymers for Emerging Technologies
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• pp.199-199
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• 2006

Microwave-irradiation has become a common heat source in organic chemistry in the last decade. In recent years, polymer chemists also discovered the advances of microwave heating that include fast and efficient heating as well as the homogeneous heat profile and the easy access to pressurized reaction conditions. In this contribution, we report our investigations on the cationic ring-opening polymerization of 2-oxazolines that lead to a tremendous acceleration from several days to several minutes polymerization time. In addition, the optimized microwave-assisted polymerization procedure was applied for the preparation of libraries of diblock and triblock copolymers that were used for the determination of structure-property relationships in poly(2-oxazoline)s.

• Journal of Electrochemical Science and Technology
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• 제13권3호
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• pp.390-397
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• 2022

The use of microwaves as the energy source for synthesis and sintering of ceramics offers substantial advantages compared to conventional gas-fired and electric resistance furnaces. Benefits include much shorter processing times and reaching the sintering temperature more quickly, resulting in superior final product quality. Most oxide ceramics poorly interact with microwave irradiation at low temperatures; thus, a more complex setup including a susceptor is needed, which makes the whole process very complicated. This investigation pursued a new approach, which enabled us to use microwave irradiation directly in poorly coupled oxides. In many solid-state electrochemical devices, the support is either metal or can be reduced to metal. Metal powders in the support can act as an internal susceptor and heat the entire cell. Then sufficient interaction of microwave irradiation and ceramic material can occur as the sample temperature increases. This microwave heating and exothermic reaction of oxidation of the support can sinter the ceramic very efficiently without any external susceptor. In this study, yttria stabilized zirconia (YSZ) and a Ni-YSZ cermet support were used as an example. The cermet was used as the support, and a YSZ electrolyte was coated and sintered directly using microwave irradiation without the use of any susceptor. The results were compared to a similar cell prepared using a conventional electric furnace. The leakage test and full cell power measurement results revealed a fully leak-free electrolyte. Scanning electron microscopy and density measurements show that microwave sintered samples have lower open porosity in the electrode support than conventional heat treatment. This technique offers an efficient way to directly use microwave irradiation to sinter thin film ceramics without a susceptor.

• 한국식품영양학회지
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• 제17권2호
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• pp.186-192
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• 2004

본 연구는 다시마 가공식품과 증간소재를 개발하기 위하여 다시마의 연화방법을 검토하였다. 그 결과 가열하면서 sodium triphospto를 0.3％첨가한 것이 연화에 가장 좋은 효과를 나타내었으며 이 때 다시마의 유연성과 퍼짐성도 좋은 것으로 나타났다. 다시마의 블랜칭은 microwave를 사용하는 것이 연화에 좋았으며, 그 정도는 microwave>스팀>끓는 물 순이었다. 또한 블랜칭할 경우 sodium triphosphate를 0.3％ 첨가하면 연화에 시너지효과가 나타났다. 색깔의 변화는 p<0.05 수준에서 블랜칭 방법과 연화제 첨가량에 대한 유의성은 확인되었다.

• 한국결정성장학회지
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• 제8권2호
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• pp.255-262
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• 1998

재래식 열원과 마이크로파 열원에 의해 열처리된 봉착용 무정형재료의 결정화 거동을 비교 검토하였다. X-선 회절분석과 SEM 분석의 결과로부터 마이크로파 열원에 의해 열처리된 시편은 짧은 열처리 시간과 낮은 열처리 온도에도 불구하고 재래식 열원에 의해 열처리된 시편에 비하여 $PbTiO_3$ 결정이 잘 성장하였고 높은 결정화도를 보여주었다. 마이크로파가 $PbTiO_3$ 결정의 핵 생성 단계에서는 핵 생성을 억제하지만,$PbTiO_3$결정의 핵 생성이 활발하여 임계 크기 이상으로 $PbTiO_3$결정이 성장하면 시편내의 이온들에게 향상된 확산 효과를 제공하여 $PbTiO_3$ 결정의 성장을 돕는다고 사료된다.

• 대한의용생체공학회:의공학회지
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• 제27권6호
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• pp.357-364
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• 2006

Microwave Radiometry is the spectral measurement of eleclromagnetic radiation at frequency bands in the microwave region. One particular application of Microwave Radiometry is for analyzing temperature difffrentials of inside of human body to detect and diagnose pathologic conditions in which the temperature differentials are related with the symptoms of certain diseases. To accomplish this aim, we propose a new calibration method for estimating subcutaneous temperature by Microwave Radiometer and we also suggest a tumor-imitator phantom structure for simulating heat diffusion propagated by tissues around tumors to evaluate the discernment of brighuless temperature difffrentials.

• 한국세라믹학회지
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• 제48권6호
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• pp.577-583
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• 2011

Stabilized biocompatible superparamagnetic iron oxide nanoparticles (SPIONs) were prepared by controlled coprecipitation method for hyperthermia application. ESR measurements determined that all of the interactions in the individual SPIONs (1 nm and 11 nm) were antiferromagnetic in nature because the ions contributed to the magnetization with a range of magnetic moments. In-situ monitoring of the temperature increment was performed, showing that the microwave absorption rate of the SPIONs was dispersed in an appropriate host media (polar or non-polar solvents) during microwave irradiation. Microwave absorption energy rates and heat loss of SPIONs in solvent were calculated by non-linear data fitting with an energy balance equation. The microwave absorption rates of SPIONs dispersed in solvent linearly increases when the concentration of SPIONs increases, implying that the microwave absorption rate can be tunable by changing the concentration of SPIONs.