• Journal of Environmental Science International
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• v.15 no.4
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• pp.341-347
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• 2006

Adsorption characteristics of benzene by zeolite were investigated using irradiating microwave. Experimental apparatus was applied to a U-type fix-bed column equipped with microwave system. Zeolite, itself, seems to be inappropriated to remove benzene because of a hygroscopic property, Microwave irradiation to zeolite, however, brings about decreasing $H_{2}O$ adsorption and increasing benzene adsorption. This causes that the dipole material such as $H_{2}O$ was vibrated and heated by irradiation of microwave and desorbed from zeolite. And then, benzene starts to be absorbed by zeolite. In this study, the results showed that the selective adsorption of benzene was occurred by the microwave irradiation and the adsorption capacity of benzene was increased by increasing microwave energy. As a results, it was found that the zeolite could be used to adsorb benzene with microwave and this method make it feasible simultaneously to adsorb and desorb benzene.

• Bulletin of the Korean Chemical Society
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• v.31 no.4
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• pp.981-983
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• 2010

The condensation of several aromatic/heteroaromatic aldehydes with 2-aminothiophenol catalyzed by silica sulfuric acid under microwave irradiation afforded 2-arylbenzothiazoles in high yields and short reaction times under solvent-free conditions. The major advantages of the present method are good yields, ecofriendly, reusable catalyst, mild and solvent-free reaction conditions.

• Current Research on Agriculture and Life Sciences
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• v.32 no.3
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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.

• 한국정보디스플레이학회:학술대회논문집
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• 2008.10a
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• pp.788-791
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• 2008

ZnO nanoparticle was successfully prepared by microwave irradiation method in various oxygen/nitrogen ratio atmospheres. The product prepared in a low oxygen ratio atmosphere showed tetra pod shape with high aspect ratio, c/a. PL spectra of the products showed higher UV emission intensity than the others when it was prepared in the atmosphere oxygen/nitrogen=40/60.

• Bulletin of the Korean Chemical Society
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• v.34 no.1
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• pp.174-178
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• 2013

A highly reliable dealkylation protocol of alkyl aryl ethers, whose alkyl groups are longer than methyl group, has been developed. We report that various ethyl, n-propyl, and benzyl aryl ethers are successfully cleaved using an ionic liquid, 1-n-butyl-3-methylimidazolium bromide, [bmim][Br], under microwave irradiation. Despite many characteristics such as lower cost and less toxicity of the alkylating agents, and greater hydrophobicity of the products, longer alkyl ethers have been significantly less exploited than methyl ethers, probably due to more difficulty in the deprotection step. Since it has the same advantages as the demethylation method developed by this group including mild conditions, short reaction time, and small use of the ionic liquids, the dealkylation protocol can greatly encourage the broader use of longer alkyl groups in the protection of phenolic groups. As with our previous study of demethylation using [bmim][Br], the microwave irradiation is crucial for the deprotection of longer alkyl aryl ethers. Unlike the conventional heating, which causes either low conversion or decomposition, the microwave irradiation seems to more effectively provide energy to cleave the ether bonds and therefore suppresses the undesired reactions.

• The Journal of Korean Academy of Prosthodontics
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• v.28 no.2
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• pp.109-124
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• 1990

The purpose of this study was to investigate the physical propertise and determine whether three were any differences in the amount of porosity of the denture base resins cured by microwave irradiation and conventional water bath heating. The resins used in this study were K-33 resin and Acron MC resin. The properties selected were transverse strength, Knoop hardness, and density. A ten-power eyepiece and scanning electron microscope(Magnification of ${\times}$ 30and ${\times}$150)were used to examine the specimens for porosity. Through analyses of the data from this study, the following conclusions were obtained. 1. Microwave energy can be effectively use dtopolymerize poly(methylmethacrylate) denture base resins. 2. In the transverse strength, K-33 resin cured by microwave irradiation was the first highest, water bath cured K-33 resin the second, microwave cured Acron MC resin the third, water bath cured Acron MC resin the fourth. 3. In the Knoop hardness, K-33 resin cured by microwave irradiation was the first hardest, water bath cured K-33 resin the second, water bath cured Acron MC resin the third, microwave cured Acron MC resin the the fourth. 4. No significant difference was found between the density of resin denture bases polymerized by either method. 5. K-33 resin showed the most porosity for the microwave curing. But there was no significant difference in the Acron MC resin and other curing method.

• Journal of the Korean Crystal Growth and Crystal Technology
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• v.20 no.6
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• pp.295-300
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• 2010

Metathetic route for the $MWO_4$ (M=Zn, Co) particles is a simple method of synthesis and a viable alternative method in a short time. $MWO_4$ (M=Zn, Co) particles were synthesized using solid-state metathetic (SSM) method with microwave irradiation. The $MWO_4$ (M=Zn, Co) particles were formed completely at $600^{\circ}C$ for 3 h. The crystallization process, thermal decomposition and morphology of the $MWO_4$(M= Zn, Co) particles were evaluated. The characteristics of the SSM reaction and the formation of a high lattice energy by-product NaCl were discussed.

• Journal of Korean Society of Environmental Engineers
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• v.27 no.7
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• pp.732-738
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• 2005

The purpose of this study is the presentation of the proper microwave treatment conditions by means of the investigation of the effect of microwave irradiation on the dewaterability and dryability of sludge. For the improving of dewatering efficiency of sludge using the microwave, the proper time of microwave irradiation is very important. The dewatering efficiency of thickening sludge conditioned by microwave irradiation for proper time was considerably improved with reducing of capillary suction time from 52.3 sec to 30.8 sec, and the sludge conditioned by microwave irradiation had contained the moisture of 81.4% after that pressure filtrationed. The result of drying characteristics of dewatered sludge using the microwave irradiation and furnace heating, for drying of sludge to moisture of below 55%, microwave irradiation time was required 3 min, whereas, furnace heating was required 40 min at $105^{\circ}C$, 20 min at $170^{\circ}C$ and 9 min at $300^{\circ}C$, respectively. We certified that the drying of dewatered sludge using the microwave irradiation was effectively reduction of moisture of sludge compare to traditional heating method.

• Bulletin of the Korean Chemical Society
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• v.32 no.11
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• pp.4001-4004
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• 2011

Various 5-substituted 1H-tetrazole derivatives were synthesized in a simple and environmentally benign method from the reaction of aryl and benzyl nitriles with sodium azide in solvent-free media using montmorillonite K-10 clay as solid recyclable heterogeneous acidic catalyst and microwave irradiation in good yields and short reaction times.

• Bulletin of the Korean Chemical Society
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• v.26 no.11
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• pp.1701-1705
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• 2005

We have established an efficient method for the synthesis of the arylpiperazine derivatives in which the acylation of 2-aminopyridine, the coupling reaction of the acyl compound with piperazines, and reduction of the arylpiperazines were performed under a microwave irradiation (300 W) to afford the corresponding target compounds in quantitative yields. In all cases, the reaction times were remarkably reduced when compared with those of the conventional method.