• 한국식품저장유통학회지
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• 제9권3호
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• pp.332-337
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• 2002

마이크로웨이브 추출방법과 환류 냉각 추출방법을 비교한 결과, 물과 에탄올의 혼합용매로 추출한 경우 마이크로웨이브 추출 방법에 의하여 추출시간을 단축시키면서 환류 냉각 추출 방법에서와 같은 수준의 가용성 고형분 및 총 폴리페놀 함량을 갖는 곰취 추출물을 얻을 수 있었다. 마이크로웨이브 추출시 최적 마이크로웨이브 에너지는 120∼150 W 였고 추출시간은 4∼8분이 적당하였다. 추출에 사용한 용매들 가운데 에탄올, 메탄올 보다 물 그리고 물과 에탄올 또는 메탄올 혼합용매를 사용한 추출물의 가용성 고형분, 총 폴리페놀 함량 및 항산화 효과가 높은 것으로 나타났다.

• 한국재료학회지
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• 제11권11호
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• pp.941-946
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• 2001

Conductive microspheres with a density of 0.2 g/cc were fabricated by electroless silver plating for application to the light-weighted microwave absorbers. The silver plating was conducted with the variation of plating conditions (sensitizing condition, $AgNO_3$, concentration, amount of reducing agent). Specimens have very low electro-resistivity. Under an optimum processing condition, conductive microspheres with uniform silver plating layer can be produced. Rubber-sphere composites were fabricated and their microwave absorbing properties were measured by HP8722D Network Analyzer. It was found that the lower the electrical resistance of microsphere, the better the microwave absorbing properties. Feasibility of microwave absorbers using this microspheres can be demonstrated with the result of microwave reflection loss of -15 dB and thickness of 1.44 mm.

• Bulletin of the Korean Chemical Society
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• 제32권6호
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• pp.1957-1964
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• 2011

Various reaction conditions uding temperature, time and type and concentration of templates have been changed in order to facilely synthesize, especially with microwave (MW) heating, SAPO-34 molecular sieves. SAPO-34 molecular sieve can be synthesized rapidly with microwave irradiation from a gel containing tetraethylammonium hydroxide (TEAOH) as a template. However, other several templating molecules lead to SAPO-5 molecular sieve under microwave irradiation even though SAPO-34 is obtained by conventional electric synthesis from the same reactant gels. Moreover, SAPO-34 can be obtained more easily by increasing the TEAOH or silica concentration or by increasing the reaction temperature. SAPO-34 can be obtained within 5 min in a selected condition (high temperature of 210 $^{\circ}C$) with microwave heating, which may lead to a continuous production of the important material. SAPO-34 synthesized by microwave irradiation is homogeneous and small in size and shows acidity and a stable performance in the dehydration of methanol and 2-butanol to olefins, suggesting potential applications in acid catalysis.

• 한국환경과학회지
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• 제22권1호
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• pp.83-89
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• 2013

Silicon carbide with aluminium oxide was used to remove the sulphur hexafluoride ($SF_6$) gas using microwave irradiation. The destruction and removal efficiencies (DREs) of $SF_6$ were studies as a function of various decomposition temperatures and microwave powers. The decomposition of $SF_6$ gas was analyzed using GC-TCD. XRD (X-ray powder diffraction) and XRF (X-ray Fluorescence Spectrometer) were used to characterize the properties of aluminum oxide. DREs of $SF_6$ were increased as the microwave powers were increased. Additive aluminium oxide on SiC increased the removal efficiencies and decreased the decomposition temperature. The XRD results show that the ${\gamma}-Al_2O_3$ was transformed to ${\alpha}-Al_2O_3$ during $SF_6$ decomposition by microwave irradiation. It was found that the best material to control $SF_6$ was SiC with $Al_2O_3$ 30 wt% in consideration of microwave energy consumption and $SF_6$ decomposition rate.

• 한국안전학회지
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• 제22권5호
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• pp.27-32
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• 2007

We investigated the damage of the TTL ICs which manufactured five different technologies by artificial microwave. The artificial microwave was rated at a microwave output from 0 to 1000W, at a frequency of 2.45GHz. The microwave power was extracted into a standard rectangular waveguide(WR-340) and TTL ICs were located into the waveguide. TTL ICs were damaged two types. One is breakdown which means no physical damage is done to the system and after a reset the system is going back into function. The other is destruction which means a physical damage of the system so that the system will not recover without a hardware repair. TTL SN74S08N and SN74ALS08N devices get a breakdown and destruction occurred but TTL SN74LS08N, SN74AS08N and 74F08N devices get a destruction occurred. Also destructed TTL ICs were removed their surface and a chip conditions were analyzed by SEM. The SEM analysis of the damaged devices showed onchipwire and bondwire destruction like melting due to thermal effect. The tested results expect to be applied to the fundamental data which interprets the combination mechanism of the semiconductors from artificial microwave environment.

• 신재생에너지
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• 제9권2호
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• pp.5-14
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• 2013

The efficiency of microwave-assisted acid hydrolysis of seaweeds for the production of ethanol was investigated and its effect on hydrolysis into reducing sugar and fermentation into ethanol evaluated as compared with those by conventional heating. A brown seaweed, Laminaria japonica (10-100g/L) was hydrolysed under dilute acidic condition (0.5N $H_2SO_4$, $100^{\circ}C$) with two sorts of heating: microwave irradiation for ${\leq}10min$ and conventional heating for 10-60min. Microwave-assisted hydrolysis was shown to be more efficient. A similar range of reducing sugar and ethanol yields as with the conventional autoclave heating procedure(${\geq}30min$) was observed, but it was obvious that production of ethanol from microwave-assisted hydrolysis had a 3 times faster reaction rate leading to very short production times, lower energy consumption/loss than from the conventional heating mode, and higher biomass loading without significant reducing ethanol yield, thus microwave-assisted acid hydrolysis is a potential alternative method for more effective hydrolysis of Laminaria japonica.

• Journal of the Korean Wood Science and Technology
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• 제23권3호
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• pp.73-82
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• 1995

Black locust trees(Robinia pseudo-acacia L.) are growing widely in Korea and have been used to get honey and animal feed, but they have seldom been used as manufacturing materials. This study was carried out to evaluate the possibility of using black locust as bent-wood furniture materials. Softening methods were steaming and micro-wave heating. The specimens of 15${\times}$15${\times}$350mm were all air-dried. For softening, specimens were steamed at 100$^{\circ}C$ for 7 min, or microwave heated for 35 seconds. It is known that microwave heating softens wood much faster than steaming. The bending processing conditions are showed in Table 7. The minimum solid-bending radii of black locust were 40mm for steaming and 150mm for micro-wave heating, respectively. In conclusion the steamed black locust, showed very good solid bending properties, but the bending properties of micro-wave heated black locust were not sufficient for bent-wood furniture.

• 자원리싸이클링
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• 제15권5호
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• pp.11-16
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• 2006

폐 폴리스티렌과 모터 오일의 혼합물로부터 마이크로웨이브 열분해를 이용하여 유용한 고분자 원료물질의 회수를 위한 연구를 수행하였다. 마이크로웨이브 반응기로 quartz tube를 사용하였으며 마이크로웨이브 흡수체로 실리콘 카바이드를 사용하였다. 공정 변수로 마이크로웨이브 입력 파워를 180에서 250 W까지 변화시켰으며, 마이크로웨이브 조사시간을 30분에서 1시간까지 변화시키며 실험하였다. 열분해를 통하여 얻어진 생성물을 GC/MS를 사용하여 분석한 결과 스티렌, 메틸 스티렌, 톨루엔, 그리고 에틸벤젠이 4개의 주요 회수 성분이었으며, 이 중 폴리스티렌으로부터 스티렌의 회수율은 약 50% 이었다. 열분해에 마이크로웨이브를 사용함으로써 일반 열분해 보다 훨씬 낮은 온도에서 열분해가 이루어졌다.

• 대한통합의학회지
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• 제5권3호
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• pp.63-70
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• 2017

Purpose : The purpose of this study was to investigate the effects of the virtual reality exercise program on ankle balance with ankle taping or microwave. Methods : This study was performed on 18 subjects. Eighteen subjects were divided into two groups; conducted virtual reality exercises with taping (n=9), and performed virtual reality exercises after microwave application (n=9). Both groups performed the exercise three times a week for four weeks. The data was analyzed by the Wilcoxon signed-rank test for comparing before and after changes of factors in each group and performed the Mann-Whitney test for comparing groups. Result : Taping and microwave groups were increased dynamic balance after virtual reality exercises (p<.05). There was no significant difference in balance after applying taping and microwave for virtual reality exercises (p<.05). Conclusion : Reducing the frequency of recurrent ankle sprain in functional ankle subjects, it is recommended to perform virtual reality exercise after applying taping and microwave.

• 한국표면공학회지
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• 제42권3호
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• pp.139-144
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• 2009

A microwave plasma torch at the atmospheric pressure by making use of magnetrons operated at the 2.45 GHz and used in a home microwave oven has been developed. This electrodeless torch can be used to various areas, including industrial, environmental and military applications. Although the microwave plasma torch has many applications, we in the present work focused on the microwave plasma torch operated in pure steam and several applications, which may be used in future and right now. For example, a high-temperature steam microwave plasma torch may have a potential application of the hydrocarbon fuel reforming at one atmospheric pressure. Moreover, the radicals including hydrogen, oxygen and hydroxide molecules are abundantly available in the steam torch, dramatically enhancing the reaction speed. Also, the microwave plasma torch can be used as a high-temperature, large-volume plasma burner by injecting hydrocarbon fuels in gas, liquid, and solid into the plasma flame. Finally, we briefly report treatment of soils contaminated with oils, volatile organic compounds, heavy metals, etc., which is an underway research in our group.