• Resources Recycling
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• v.20 no.3
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• pp.62-67
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• 2011

This study has been investigated for characteristic of removal on the effect of changes in soil moisture, microwave power, and temperature through the decomposition of oil-contaminated soil under high temperature conditions with high temperature heating elements and microwave. A lubricating oil having long carbocyclic(C18-C50) commonly known as a non-resolvable material was treated and the efficient for removal of TPH(Total Petroleum Hydrocarbon) obtained 85.2% at 6 kW and $700^{\circ}C$ and thus the contaminant was found to be removed to 1788 mg/kg for 40 minutes. In case of contaminated soil by light oil and gasoline, the amount of removal was achieved with 567 mg/kg at 6 kW, 500 for 20 minutes that corresponds to reach 98.4% of treatment efficient. In addition, non-resolvable materials contaminated by oil reached TPH concentration on 2,000 mg/kg of worrisome level of soil contamination in the 3-zone at 6kW, $700^{\circ}C$, and 30 minutes, and processing cost at this time was about 8,173 won per ton.

• Journal of the Korean Geotechnical Society
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• v.32 no.11
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• pp.21-29
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• 2016

In this study, recycled aggregates crushed from waste concrete were sorted into three groups, 10-13 mm, 13-20 mm, and 20-25 mm. They were treated in different ways and then their crushability was evaluated for each treatment. Coffee waste was used for reducing their pH level. The pH of recycled aggregate was almost 11, regardless of aggregate sizes. The pH of coffee waste was nearly 5 and 10, 30, or 50 g of coffee waste was mixed with 1000 ml of distilled water and recycled aggregates. The lowest pH was about 6.2 when 50 g of coffee waste was mixed. Aggregates were treated with microwave or soaked for 1 day in vinegar (pH = 2) for neutralization reaction. Microwave treated and neutralized aggregates showed 3.3% and 6.2% higher crushing values compared to non-treated one, respectively. Neutralized treatment was more effective for crushing. In crushing tests, a sample height of 120 mm was tried, which gave 6.3% higher crushing value. A four stepped loading with each 100 kN gave 7.1% higher crushing value, compared to standard 100 mm height and 400 kN continuous loading.

• Journal of Environmental Science International
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• v.19 no.3
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• pp.379-387
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• 2010

Sediments of Little Scioto (LS) River in Ohio was contaminated by poor disposal of creosote from Baker Wood Creosoting Facility. Among the primary compounds of creosote, Polycyclic Aromatic Hydrocarbons (PAHs) are the most common ingredient PAHs are known for toxic, carcinogenic and mutagenic compounds. There are many difficulties to remove the PAHs in nature environment because their characteristics are having a less water-solubility, volatile and low mobility properties as increasing the molecular weight. The generation of hydroxyl radicals (${\cdot}OH$) and hydrogen peroxide ($H_2O_2$) forms as well as high temperature (5000 K) and pressure (1000 atm) by a physico-chemical effects of ultrasound during a cavitation collapse can promote the degradation and desorption of PAHs in sediment And it can also produces shock wave and microjets which are able to change the size and surface of particle in solid-liquid system as one of physical effects. Therefore, we explored to understand the role of particle size, the effect of elimination for PAHs concentration by ultrasound and optimize the conditions for ultrasonic treatment. The condition of various size of particles (> $150{\mu}m$, < $150{\mu}m$) and solid-liquid ratio (12.5g/L, 25g/L) for the treatment was considered and ultrasonic power (430 W/L) with liquid - hexane extraction and microwave extraction method were applied after ultrasound treatment.

• Journal of the Korean Society of Food Science and Nutrition
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• v.35 no.5
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• pp.649-654
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• 2006

It was investigated the effects of pre-treatment method on the microbes on the surface of radish (Raphanus sativus L.) leaves. Independent variables put in water washing ($X_1$), microwave treatment ($X_2$) and steam treatment ($X_3$) using central composite design and response surface analysis. It was not detected in the pathogenic microbes, Samonella spp., Camphylobacter spp., Vibrio spp., Shigella spp., Staphyloccocus spp., on the surface of collected radish leaves without pre-treatment. But general microbes showed $3.90{\times}10^5{\sim}1.20{\times}10^7CFU/g$ of total microbes, $1.10{\times}10^2{\sim}2.00{\times}10^5CFU/g$ of E. coli, $2.40{\times}10^3{\sim}3.55{\times}10^6CFU/g$ of yeast/mold on the surface of various radish leaves and lactic acid bacteria was detected or not according to collected samples. The best method of pre-treatment was steam treatment on the microbe reduction effect of samples surface. Also, the multiplex regression coefficients analysis was calculated three independent variables ($X_1,\;X_2,\;X_3$) and dependent variables (total microbes, lactic acid bacteria and yeast/molds). It showed high correlation $R^2$, 0.89, 0.87, 0.85, respectively. For effective reduction of surface microbes, the best method was water washing with microwave or steam treatment at the same time.

• Food Science of Animal Resources
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• v.29 no.6
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• pp.709-718
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• 2009

The purpose of this study was to search for physical treatments to reduce allergenicity of pork. Physical treatments such as heating, autoclave, microwave, sonication, and irradiation have been used for food processing or reduction of allergenicity. The porcine serum albumin (PSA), known as a major allergen in pork, was extracted after physical treatments. The antigenicity of pork extracts by heating (80 and $100^{\circ}C$ for 20 min), autoclave ($121^{\circ}C$ for 5, 10, and 30 min), and microwave (for 5 and 10 min) was significantly decreased. Especially, the binding ability of p-IgG to pork extracts by autoclave for 30 min showed the greatest decrease (about 3%) in physical treatments. However, the antigenicity of pork was unaffected by sonication and irradiation treatment. These results indicated that the autoclave treatment was the most effective method to reduce the antigenicity of pork.

• Environmental Engineering Research
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• v.22 no.1
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• pp.12-18
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• 2017

Struvite precipitation has been proven to be an effective method in removing and recovering ammonia nitrogen (N) and phosphate phosphorus (P) from wastewater. In this study, effects of pH, molar ratios and pre-treatment of effluent of anaerobically digested swine wastewater were investigated to improve struvite crystallization. The magnesium : ammonium : phosphate ratio of 1.2 : 1.0 : 1.0 was found to be optimal, yet the molar ratio in the wastewater was 1 : 74.9 : 1.8. From the analysis, the optimum pH was between 8.0 and 9.0 for maximal phosphate P release and from 8.0 to 10.0 for maximal ammonia N and phosphate P removal from real wastewater. Analysis from Visual MINTEQ predicted the pH range of 7-11 for ammonia N and phosphate P removal and recovery as struvite. For pre-treatment, microwave pre-treatment was ineffective for phosphate P release but ultrasound pre-treatment showed up to 77.4% phosphate P release at 1,000 kJ/L of energy dose. Precipitates analysis showed that phosphorus and magnesium in the collected precipitate had almost same values as theoretical values, but the ammonia content was less than the theoretical value.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.58 no.1
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• pp.67-70
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• 2013

This research study was to develop methods for inhibiting the germination of cotton seeds. Germination rates after heating treatment at $80^{\circ}C$ with 10, 20, 30, 40 min. were 9.3, 9.3, 5.3 and 1.3 percentage, respectively. Heat treatment over $85^{\circ}C$ with 10 min. caused no germination of cotton seeds. Germination was significantly reduced with gamma rays treatment more than 10,000 gy, while the treatment within 2,000-8,000 gy induced less effects. Microwave processing for 30 seconds and 60 seconds inhibit the germination of cotton seed under 8 and 0%, respectively. As a physical treatment, rollmill milling with 1.5, 2, 2.5 mm gap inhibited any germination of cotton seeds. The optimum gap of roll-mill for processing physical cracking was below 51% of the thickness of seed.

• Proceedings of the Korea Association of Crystal Growth Conference
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• 1999.06a
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• pp.337-350
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• 1999

Thick diamond film having ~700${\mu}{\textrm}{m}$ thickness was deposited on polycrystalline molybdenum (Mo) substrate using high power (4kW) microwave plasma enhanced chemical vapor deposition (MPECVD) system. We could achieve free-standing diamond film via detaching as-deposited diamond film from the substrate by rapid cooling them under vacuum. We investigated the variation of photoconductivity after exposing the film surface to either oxygen or hydrogen plasma. At as-grown state, the growth side (the as-grown surface of the film) showed noticeable photoconductivity. The oxygen plasma treatment of this side led to the insulator. After exposing the film surface to hydrogen plasma, on the other hand, we could observe the reappearing of photoconductivity at the growth side. Based on these results, we suggest that the hydrogen plasma treatment may enhance the photoconductivity of free-standing diamond film.

• Journal of the Korean Crystal Growth and Crystal Technology
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• v.9 no.4
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• pp.441-445
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• 1999

Thick diamond film having $~700\mu\textrm{m}$ thickness was deposited on polycrystalline molybdenum(Mo) substrate using high power (4 kW) microwave plasma-enhanced chemical vapor depostion (MPECVD) system. We could achieve free-standing diamond film via detaching as-deposited diamond film from the substrate by rapid cooling them under vacuum. We investigated the variation of photoconductivity after exposing the film surface to either oxygen or hydrogen plasma. At as-grown state, the growth side (the as-grown surface of the film) showed noticeable photoconcuctivity. The oxygen plasma treatment of this side led to the insulator. After exposing the film surface to hydrogen plasma, on the other hand, we could observe the reappearing of photoconductivity at the growth side. Based on these results, we suggest that the hydrogen plasma treatment may enhance the photoconductivity of free-standing diamond film.

• Nuclear Engineering and Technology
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• v.50 no.3
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• pp.526-530
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• 2018

Human fingernails were used to estimate the radiation dose via electron paramagnetic resonance measurements of radiation-induced radicals. The limiting factors in this research were mechanically induced electron paramagnetic resonance signals due to the mechanical stress during the preparation of the samples. Therefore, different treatment methods of fingernails were used to reduce the mechanically induced signals. The results demonstrate that the mechanically induced and radiation-induced signals have apparently different microwave power saturation behaviors. In addition, the mechanically induced signal shows a fading evolution over time and reaches a constant value. Chemical treatment using the different reagents showed that the minimum mechanically induced signal was obtained using the dithiothreitol reagent. The dose-response curves of the samples treated with dithiothreitol for 30 minutes demonstrated a greater linearity than those of samples treated for 5 minutes. Therefore, to find an unknown absorbed dose in a fingernail sample using a calibration curve, we recommend adopting the mentioned chemical treatment procedure to reduce the uncertainty.