There are some problems like aggregation and bubble formation around nuclei in process of microwave-assisted nanoparticle synthesis. To solve them, anti-solvent addition was tried in this study, and the mechanism of fine particle was considered through the results of size profiles obtained from in-situ observation tool of dynamic light scattering equipped with microwave reactor. First, when iron (III) sulphate (Fe₂(SO₄)₃) solution is heated up by microwave, larger particle and larger bubble during the irradiation, and aggregation after the irradiation were observed. Secondly, by the addition of ethylene glycol as an anti-solvent, bubble and particle sizes became smaller. This is because microwave absorbance energy is distributed to more particles in the solution with higher suspension density, which are promoted by the quick thermal response and the anti-solvent effect, the energy per one particle became lower. At the same time, the anti-solvent addition could prevent aggregation of particle due to the decrease in ionic strength of aqueous solution with anti-solvent.

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We developed a method for in situ fabrication of f unctional material s in side the fiber by microwave selective heating . Th e method has three steps First, the raw material solution is absorbed to the fiber. Second , the fiber is immersed and pressurized in immiscible liqu ids with the raw material solution. Finally, the functional materials are in situ fabricated inside of the fiber by the microwave selective heating. As a model reaction, we fabricated silver nanoparticle in duced cotton fiber. The elemental silver was distributed inside of the fiber in a cross sectional distribution as confirmed by SEM EDS. The silver induced cotton has ability of the a nti bacterial functions an d launderability W e also fabricated zeolite particles inside porous PTFE fibers as another demonstration.

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When we heat materials such as coffee beans or sesame over a fire, we usually stir them to get uniform heating. But it is not easy to do it in microwave applicator. If there is a stirring mechanism, unexpected sparks or discharges caused by microwave energy are generated around the mechanism. They are the loss of the energy and may damage both materials and applicator. This is a new microwave heating mixer without stirring mechanism, and it can heat materials uniformly and efficiently with no sparks or discharges.

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Microwave-assisted catalytic oxidation process is expected to be an alternative pollution control technology to the supported metal catalyst combustion method. Perovskite-type oxides containing transition metals as B-sites have high oxidation capabilities and excellent temperature enhancement properties by microwave heating. In this paper, we report on LaMnO₃ The effects of sample treatment conditions, such as catalyst calcination temperature, grain preparation conditions, and post-heating treatment, were investigated in detail.

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The development of a direct methane decomposition process has been studied by combining a microwave heating reactor with a catalyst. The catalyst consisted of five layers: SiC layer as a susceptor to absorb microwave, and a layer consisting of a physical mixture of Ni, HZSM-5 zeolite and Mo2C as a catalyst for methane decomposition. Under microwave irradiation, the catalyst activity was maintained for 80 hours. The key substance for catalytic activity is formed Ni-CNO; Ni-carbon nano-onion, which is generated by the interaction of carbon species during methane decomposition and Ni particles. In this paper, the functions of Ni-CNO are described from the viewpoint of catalysis and energy supply.

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Microwaves (MW) are applied to a variety of situations including daily life, industry, and medical care. In addition, the biological effects of MW are attracting more attention than ever before. Various researches of MW effects on life phenomena has been conducted. However, detailed mechanisms of such effects have been rarely investigated based on biology and chemistry. In the last two decades, it has been reported to improve cellular functions or to have negative effects on cells. Very recently, cellular researches have been conducted with the aim of applying MW to cancer treatment. Hyperthermia has already been in practical use, and other methods are now under investigation. This review summarizes some researches about effect of MW on cells and show some applied researches on cancer treatment. These studies could contribute to various applications including medical treatment.

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[in Japanese]

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[in Japanese]

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