• Journal of the Korean Ceramic Society
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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.

• Carbon letters
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• 제15권1호
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• pp.15-24
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• 2014

As a part of the electromagnetic spectrum, microwaves heat materials fast and efficiently via direct energy transfer, while conventional heating methods rely on conduction and convection. To date, the use of microwave heating in the research of carbon-based materials has been mainly limited to liquid solutions. However, more rapid and efficient heating is possible in electron-rich solid materials, because the target materials absorb the energy of microwaves effectively and exclusively. Carbon-based solid materials are suitable for microwave-heating due to the delocalized pi electrons from sp2-hybridized carbon networks. In this perspective review, research on the microwave heating of carbon-based solid materials is extensively investigated. This review includes basic theories of microwave heating, and applications in carbon nanotubes, graphite and other carbon-based materials. Finally, priority issues are discussed for the advanced use of microwave heating, which have been poorly understood so far: heating mechanism, temperature control, and penetration depth.

• New & Renewable Energy
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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.

• Food Science of Animal Resources
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• 제28권3호
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• pp.295-300
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• 2008

This study was carried out to elucidate the relationship between different fat levels (0%, 5%, 10%, 15%, 20%, and 25%) and the quality of ground pork patties cooked to reach an internal temperature of $75^{\circ}C$ in a microwave oven. The relationship between fat level and cooking rate of pork patties cooked by microwave energy was highly significant ($R^2=0.72$), and had a low determination coefficient ($R^2=0.55$). The relationship between fat level and total cooking loss of pork patties cooked by microwave energy was also very significant, with a high correlation coefficient of $R^2=0.89$. The correlation coefficient between fat level and cooking drip loss of patties cooked by microwave energy was 0.92, which was highly significant. Although the correlation coefficient between fat level and evaporation loss had a negative value ($R^2=-0.63$), there was a highly significant relationship between fat level and shear force of pork patties cooked by microwave energy.

• Applied Chemistry for Engineering
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• 제7권6호
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• pp.1027-1033
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• 1996

Under the Irradiation of the radiofrequency wave, the dipole materials vibrate as microwavic phase change. This causes friction between adjacent molecules and enables an unique charateristics of interior heating of the materials. When dipole gases are adsorbed inside of a solid radiofrequency wave absorber, the gases can be decomposed easily by the microwave energy. The decomposition of sour gases was successfully tested in this manner to develop a sour gas removal process from the combustion flue gas. The standard gas bearing NO and $SO_2$ was passed through and microwave was applied on the calcined char bed as the wave absorber and the gas adsorbent. It was found that more then 95% of NO and 70 % of $SO_2$ was decomposed to the environmentally clean elements during the passage through the 20 gram char bed under the microwave impingement. The surface area and the porosity of char increased because the oxygen radicals produced from decomposed gas attacked carbon in the char capillaries and formed $CO_2$. For a lower concentration of sour gas, general cases in the commercial combustion processes, almost complete decomposion is believed possible and this method is surely expected to be useful for the prevention of air pollutions.

• The International Journal of Costume Culture
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• 제13권1호
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• pp.62-66
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• 2010

Of all the ways that energy is consumed within textile industry, few are as high energy-expending as dyeing process. The energy consumption in dyeing process amounts to 77% of total fuel consumption, 54% of total electricity use. A technical development in terms of efficient saving energy and time as well is required in the process of dyeing textiles. Recently, dyeing experts are investigating new technologies can conserve energy grafting into microwaves, radio waves, infrared lights, etc. Dyeing industry in Korea, however, the research related to energy conservation has been rarely conducted. Accordingly, this study aims to examine the possibility where especially microwaves could be applied to reduce the energy use and enhance dyeing process skill. This study performs the experiment in which microwave is employed as heating condition in dyeing and figures out as color yield being promoted, bathochromic effect would be achieved. Applying microwaves in dyeing process is expected to lower the carbon emission, energy and time wasted, ultimately exalt economic efficiency.

• Journal of Soil and Groundwater Environment
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• 제16권3호
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• pp.28-37
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• 2011

A preliminary study for energy efficient soil heating and contaminant removal using microwave was conducted. Soils sampled from floodplain were heated with microwave oven, and soil heating property and energy efficiency were compared to those heated with electrical furnace. In addition the effects of water, soil organic matter, and contaminated diesel on soil heating with microwave were investigated. Even though the electrical power consumption of electrical furnace and microwave oven were similar, temperature of soil heated with microwave oven was significantly higher than that of soil heated with electrical furnace. The increase of soil moisture content delays the raise of soil temperature during heating it with microwave oven. However, the effects of total petroleum hydrocarbon (TPH) (<10%) in contaminated soil matrix and small amount of soil organic matter (<5%) on the increase of soil temperature by microwave were not significant. Further studies for contaminated soils with different texture using pilot scale microwave reactor are required for application of this technique in the field.

• Current Research on Agriculture and Life Sciences
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• 제32권3호
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• pp.131-134
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• 2014

The thermal death kinetics of the Black timber bark beetle, Xylosandrus germanus, was investigated to develop a heat treatment for control of infested wood packing materials used to export goods. To determine the feasibility of microwave irradiation as an alternative control method, laboratory experiments irradiating wooden blocks of Douglas fir ($200{\times}200{\times}250mm$), which were artificially infested with adults, with 2.45 GHz of microwave energy. All (100%) Ambrosia beetle adults were killed by both hot water treatments and microwave irradiation at $52^{\circ}C$ and $58^{\circ}C$, respectively. Probit analyses estimated the internal wood temperature required to produce Probit (0.99) efficacy to be $64.7^{\circ}C$ (95% CI $62.4-69.9^{\circ}C$) at one minute after microwave treatment.

• KOREAN JOURNAL OF PACKAGING SCIENCE & TECHNOLOGY
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• 제26권3호
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• pp.133-138
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• 2020

As HMR (home meal replacement) food market grows rapidly, a new packaging with more HMR specialized functions is highly required to promote consumers' convenience. A susceptor is defined as a material generating heat by absorbing electromagnetic energy such typically as radiofrequency or microwave radiation. In microwave cooking, susceptors are made of conductive metal thin film deposited on paper or plastic sheet and have generally been used to help crispen or brown foods by converting microwave energy into heat. This mini review article deals with current status of microwave susceptor packaging including commercial products, technical theory, types of susceptor and a test method for heating performance.

• Transactions of the Korean hydrogen and new energy society
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• 제30권1호
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• pp.35-42
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• 2019

Recently, the gradual increase in energy acceptance is mostly satisfied by fossil fuels, but research and development of renewable energy sources are attracting attention due to fossil fuel supply and greenhouse gas problem. The disadvantage is that renewable energy can not be produced continuously. This being so, energy storage is an important technology in renewable energy. In this study, microwave was used to convert carbon receptor-carbon dioxide to gas fuel.