• Journal of Sericultural and Entomological Science
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• v.40 no.2
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• pp.163-168
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• 1998

Hydrolysis rate and activation energy of Antheraea pernyi silk fiber treated with HCI were examined. Thermal decomposition temperature and surface morphology were also investigated by using differential scanning calorimeter and scanning electron microscope. As the concentration of hydrochloric acid and the treatment temperature increased, the hydrolysis occurred more rapidly. The activation energy of Antheraea pernyi, 74.0 kJ/mol, was higher than that of Bombyx mori, 58.1 kJ/mol. As the concentration of hydrochloric acid increases, the activation energy of Antheraea pernyi decreased from 74.0 kJ/mol to 62.0 kJ/mol. The shape of acid-resistance fraction of Antheraea pernyi became more distroyed and was transformed from fiber to powdered form with an increase of hydrolysis rate. The thermal decomposition temperature of Antheraea pernyi was 360.8$^{\circ}C$ until the hydrolysis rate was 81.8 wt%, but ti decreased to 347.0$^{\circ}C$ when the hydrolysis rate was 93.8 wt%.

• Korean Journal of Soil Science and Fertilizer
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• v.47 no.2
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• pp.127-132
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• 2014

The effect of thermal pretreatment conditions on hydrolysis characteristics of dairy manure and sawdust mixtures has been evaluated. Thermal pretreatment temperature varied between 35 and $120^{\circ}C$ and the period of the treatment changed between 30 and 1440min (24h). As thermal pretreatment temperature and duration increased, organic material solublization rates were improved. Maximum solubilizations of chemical oxygen demand (SCOD), carbohydrates, and volatile fatty acids(VFAs) were observed when dairy manure treated for one day at $120^{\circ}C$. Although one day treatment duration at $120^{\circ}C$ showed the highest SCOD, soluble carbohydrates, and VFAs concentration, its hydrolysis rate was only about 12%. The results reveal that the thermal pretreatment conditions tried in this study are not enough to solubilize the organic matter contained in dairy manure and sawdust mixtures. In order to maximize hydrolysis performance, the further research needs to determine the factors influences on organic material solubilization in addition to thermal pretreatment temperature and duration.

• Elastomers and Composites
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• v.52 no.1
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• pp.59-68
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• 2017

The effect on the hydrolysis resistance properties by the addition of maleic anhydride grafted EMDM (MA-g-EPDM) and PP (MA-g-PP) to a PA66/GF composite was investigated with respect to the mechanical properties, thermal properties, and morphology. The degree of hydrolysis of the PA66/GF composite was measured using py-GC/MS analysis. When compared to the PA66/GFcomposite in MEG/water solution, the composites where MA-g-EPDM and MA-g-PP were added to PA66/GF showed a higher degree of hydrolysis resistance, impact strength, and thermal properties, whereas their tensile strength, tensile modulus, flexural strength and flexural modulus decreased. As immersion time in the solution increases, the rate of tensile strength drop of the MA-g-PP added composite appeared lower than that of the PA66/MA-g-EPDM/GF and PA66/GF composites. The py-GC/MS analysis confirmed the formation of PA66 hydrolysis reaction by products such as carboxylic acid and alkylamine with increasing immersion time.

• Korean Journal of Soil Science and Fertilizer
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• v.48 no.6
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• pp.602-609
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• 2015

In order to enhance a biogas production by the hydro-thermal pre-treatment of piggery manure, the effects of hydro-thermal reaction temperature at thermal hydrolysis of piggery manure on the methane potential and anaerobic biodegradability of thermal hydrolysate were analyzed. The increase of hydro-thermal reaction temperature from $170^{\circ}C$ to $220^{\circ}C$ caused the enhancement of hydrolysis efficiency, and most of organic matters were present in soluble forms. However, the methane potentials ($B_u-TCOD$) of hydrolysate were decreased from 0.239 to $0.188Nm^3kg^{-1}-TCOD_{added}$ by increasing hydro-thermal reaction temperature from $170^{\circ}C$ to $220^{\circ}C$, and also the anaerobic biodegradability (DTCOD) decreased from 74.6% to 58.6% with increase of hydro-thermal reaction temperature. The increase of hydro-thermal reaction temperature from $170^{\circ}C$ to $220^{\circ}C$ resulted in the decrease of easily biodegradable organic matter content, while persistent organic matter contents increased.

• Journal of the Korea Organic Resources Recycling Association
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• v.23 no.4
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• pp.95-103
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• 2015

The purpose of this study was performed to quantitatively measure the thermal conductivity of poultry slaughter waste with variation of reaction temperature for optimal design of thermal hydrolysis reactor. We continuously quantified the thermal conductivity of dehydrated sludge related to the reaction temperature. As the reaction temperature increased, the dehydrated sludge is thermally liquefied under high temperature and pressure by the thermal hydrolysis reaction. Therefore, the bond water in the sludge cells comes out as free water, which changes the dehydrated sludge from a solid phase to slurry of a liquid phase. As a result, the thermal conductivity of the its sludge was more than 2.11 times lower than that of the water at $20^{\circ}C$. However, the thermal conductivity of the sludge approached to $0.677W/m{\cdot}^{\circ}C$ of water at $200^{\circ}C$, experimentally substantiating liquefaction of the dehydrated sludge. Therefore, we confirmed that the change in physical properties due to thermal hydrolysis appears to be an important factor for heat transfer efficiency. And the thermal conductivity function related to reaction temperature was derived to give the boundary condition for the optimal design of the thermal hydrolysis reactor. The consistency of the calculated function was 99.69%.

• Journal of Korean Society on Water Environment
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• v.31 no.2
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• pp.151-158
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• 2015

The aim of this research is to derive an optimum operating condition for the thermal solubilization equipment that is employed to increase concentration of soluble organic materials and to assess whether it would be possible to use the waste sludge generated by thermal solubilization reaction as an external carbon source in biological denitrification process. For the purpose, we have constituted a laboratory-size thermal solubilization equipment and have assessed thermal hydrolysis efficiency based on various reaction temperature and reaction time. We have also derived SDNR using the waste sludge generated by thermal solubilization reaction through a batch experiment. As a result of research, the highest thermal hydrolysis efficiency of about 42.8% was achieved at $190^{\circ}C$ of reaction temperature and at 90 minutes of reaction time. And when SDNR was derived using the waste sludge, the value obtained was $0.080{\sim}0.094\;g\;NO_3{^-}-N/g\;MLVSS{\cdot}day$, showing SDNR that is higher than that obtained by the results of existing researches that used common wastewater as an external carbon source. Accordingly, in view of the fact that food wastes vary quite a bit in characteristics based on the area they are generated from and seasonal change, it seems that a flexible operation of thermal solubilization equipment is required through on-going monitoring of food wastes that are imported to food wastes recycling facilities.

• Korean journal of food and cookery science
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• v.33 no.3
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• pp.307-315
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• 2017

Purpose: To develop nano-sized starch particles for application as dietary fiber sources in liquid food system, the morphology and thermal properties of acid hydrolyzed rice starches with different amylose contents were evaluated. Methods: Rice starches purified from three Korean cultivars, including Goami, Hopyeong, and Hwaseonchal, were hydrolyzed with 2.2 N HCl solution in a $35^{\circ}C$ shaking water bath (100 rpm) for 7, 10 and 15 days. Results: Acid hydrolysis rates of rice starches increased with increasing hydrolysis duration, and rates for Goami, Hopyeong, and Hwaseonchal were 28.74-38.50%, 38.96-49.53%, and 40.24-48.88%, respectively. The granular size of acid hydrolyzed starches decreased to 122.4-479.9 nm, whereas granular aggregation increased with increasing hydrolysis duration. In particular, waxy rice starch of Hwaseonchal was composed of many tiny granules without aggregates. Gelatinization temperature and temperature range increased with increasing hydrolysis duration. All starches showed A type crystallinity using an x-ray diffractometer, regardless of acid hydrolysis. Conclusion: It is suggested that nanoparticles could be prepared by acid hydrolysis of rice starches, and waxy rice starch is the most preferred source for application.

• Journal of the Korea Organic Resources Recycling Association
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• v.24 no.4
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• pp.49-57
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• 2016

In this study, a thermal hydrolysis technology was used to treat the poultry carcasses that were killed due to Avian Influenza (AI) occurrence, as well as to determine the possibility of fueling for the resultant products. Experimental results showed that the poultry carcasses were liquefied except for sand, and showed the optimum efficiency at $190^{\circ}C$ and operating time of 60 minutes. It has been shown that liquid products obtained after thermal hydrolysis has good conditions for fuel conversion since it had high carbon contents and calorific value, as well as low ash content. In addition, it was possible to operate the thermal hydrolysis facility by using only the waste heat generated in the combustion without injecting the auxiliary fuel, and the exhaust gas generated in the combustion has a small influence on the atmosphere.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.25 no.8
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• pp.632-638
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• 2012

The prepartion of various metal oxide nanostructures via hydrothermal method, hydrolysis, thermal evaporation and electrospinning and their applications to chemoresistive sensors have been investigated. Hierarchical and hollow nanostructures prepared by hydrothermal method and hydrolysis showed the high response and fast responding kinetics on account of their high gas accessibility. Thermal evaporation and electrospinning provide the facile routes to prepare catalyst-loaded oxide nanowires and nanofibers, respectively. The loading of noble metal and metal oxide catalyst were effective to achieve rapid response/recovery and selective gas detection.

• KSBB Journal
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• v.28 no.6
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• pp.366-371
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• 2013

Ethanol productions were performed by separate hydrolysis and fermentation (SHF) and simultaneous saccharification and fermentation (SSF) processes using seaweed, Enteromorpha intestinalis (sea lettuce). Pretreatment conditions were optimized by the performing thermal acid hydrolysis and enzymatic hydrolysis for the increase of ethanol yield. The pretreatment by thermal acid hydrolysis was carried out with different sulfuric acid concentrations in the range of 25 mM to 75 mM $H_2SO_4$, pretreatment time from 30 to 90 minutes and solid contents of seaweed powder in the range of 10~16% (w/v). Optimal pretreatment conditions were determined as 75 mM $H_2SO_4$ and 13% (w/v) slurry at $121^{\circ}C$ for 60 min. For the further saccharification, enzymatic hydrolysis was performed by the addition of commercial enzymes, Celluclast 1.5 L and Viscozyme L, after the neutralization. A maximum reducing sugar concentration of 40.4 g/L was obtained with 73% of theoretical yield from total carbohydrate. The ethanol concentration of 8.6 g/L of SHF process and 7.6 g/L of SSF process were obtained by the yeast, Saccharomyces cerevisiae KCTC 1126, with the inoculation cell density of 0.2 g dcw/L.