• Korean journal of food and cookery science
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• v.10 no.4
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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.

• Journal of the Korean Crystal Growth and Crystal Technology
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• v.10 no.1
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• pp.66-72
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• 2000

The behavior of nucleation and crystallization in the $Li_2O_3-SiO_2$ glass heat-treated at different condition under the conventional and microwave processing was studied by differential thermal analysis (DTA), X-ray diffractometry (XRD), optical microscopy (OM), and electrical conductivity measurement. Nucleation temperature and temperature of maximum nucleation rate in both conventionally and microwave heat-treated samples were 460~$500^{\circ}C$ and $580^{\circ}C$, respectively. It was expected that the probability for bulk crystallization increased in microwave heat-treated sample, compared to conventionally heat-treated one. Degree of crystallization increased with increasing crystallization temperature in both conventionally and microwave heat-treated samples. However, pattern of crystallization growth under microwave processing appeared to be quite different from that under the conventional one due to its internal or volumetric heating. Electrical conductivity of conventionally and microwave heat-treated samples were 1.337~2.299, 0.281~~$0.911{\times}10^{-7}\Omega {\textrm}{cm}^{-1}$, respectively.

• Journal of the Korean Ceramic Society
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• v.54 no.6
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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.

• The Journal of Korean Academy of Prosthodontics
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• v.34 no.4
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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).

• Proceedings of the Polymer Society of Korea Conference
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• 2006.10a
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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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• v.13 no.3
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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.

• The Korean Journal of Food And Nutrition
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• v.17 no.2
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• pp.186-192
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• 2004

This study was performed to investigate softening methods of raw sea tangle for development of sea tangle processing products and intermediate materials. In examination of various softening agents, it was revealed that 0.3％ sodium triphosphate was best effective on softening with heat treatment. Softerness and spreadability of sea tangle treated with sodium triphosphate and heat treatment were indicated to be better than the others. In blanching studies, microwave was extremely effective on softening and the effect was as follows: microwave>steaming>boiling water in softening order. In the case of adding 0.3％ sodium triphosphate in blanching treatment, there was synergy effectiveness on softening. The color change of treated sea tangle was significantly different at p<0.05 depending on blanching method and addition amount of the agent.

• Journal of the Korean Crystal Growth and Crystal Technology
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• v.8 no.2
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• pp.255-262
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• 1998

This study investigated the crystallization behaviour of sealing amorphous material heat-treated by conventional and microwave heating source. From X-ray diffraction and SEM analyses, it was shown that microwave heat-treated sample had well-grown $PbTiO_3$crystals and the high degree of crystallinity inspite of its heat-treated condition of shorten time and lower temperature as compared with a conventionally heat-treated sample. It was assumed that microwaves inhibit the nucleation of $PbTiO_3$crystal in nucleation stage, but promote the growth of $PbTiO_3$crystal above the critical size of crystal due to enhanced diffusion effect within the sample.

• Journal of Biomedical Engineering Research
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• v.27 no.6
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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.

• Journal of the Korean Ceramic Society
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• v.48 no.6
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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.