• Journal of Korea Technical Association of The Pulp and Paper Industry
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• v.33 no.5
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• pp.30-36
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• 2001

Caro's acid (persulphuric acid) has been proposed as a promising reagent used in pulping of lignocellu-losic materials. Bagass was subjected to caro's acid pulping under different pulping conditions of per acid concentration (2~8 percent), pulping temperatures (40~$60^{\circ}C$) and pulping time (120~240 min). The influence of different parameters of caro's acid pulping process on the chemical and strength properties of the produced pulps had been studied. Peracid concentration and pulping temperature are the most important variables of the pulping process. High degree of delignification and good deliberation were achieved at moderate pulping conditions in the studied range. Pulping experiments of bagasse by using caro's acid had been carried out for determination of the optimum comditions of the process. In inch case to effectively tackle the problem, a specific design of an experiment is selected depending on the goals to be achieved in the experimentation. The study could enable us to excepect the bagasse pulp properties (yield, Kappa number, DP) that be stated as function of the independent variables of caro's acid pulping process (per acid concentration, pulping temperature and pulping time).

• Mycobiology
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• v.36 no.3
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• pp.183-189
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• 2008

The production of aerial conidia of Lecanicillium lecanii 41185, a highly virulent fungus, by solid-state fermentation was studied for use as a biocontrol agent against aphids. Among several agro-industrial solid media, steamed polished rice was found to produce the highest amount of aerial conidia. The optimal conditions for aerial conidia production were determined to be a 28.5% moisture content in the rice, 25$^{\circ}C$ culture temperature, rice pH of 6.0, 75% ambient relative humidity, 4-dold seeding culture, 0.6% $KNO_3$, and 12 d of culture time. The conidia yield increased from $5.7\times10^9$ conidia/g polished rice to 18.2 $18.2\times10^9$ conidia/g polished rice following application of these optimized conditions.

• Journal of the Korean Society of Food Science and Nutrition
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• v.19 no.3
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• pp.201-206
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• 1990

The optimal cultural conditions for production of the bluish purple prgment by the cultivation of Streptomyces californicus KS-89 were determined with various substrates. The carbon and nitrogen sources on the production of pigment indicated that soluble strarch and glycerol as carbon sources and sodium glutamate sodium nitrate as nitrogen sources given a mzimum yield of the pigment at 3$0^{\circ}C$ for 7 days. The addition of ferrous sulfate was essential. The highest production of pigment was observed with cultivation in a medium containing 2.0% soluble starch 1% glycerol 0.5% sodium glutamate 0.05% sodim nitrate 0.001% L-proline 0.025% K2HPO4 0.005% MgSO4 .7H2O, 0.04% FeSO4.7H2O, 0.001% thiamine.HCl and pH7.0.

• Bulletin of the Korean Chemical Society
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• v.6 no.3
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• pp.138-140
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• 1985

Hydroxylation of anisole with $H_2O_2$ was investigated by employing Fe(III) ion and N-dodecyl-3,4-dihydroxybenzamide (DDHB) as a catalyst. The study was aimed at obtaining an insoluble catalyst with a long catalytic life, in view of the inactivation of the catechol portion of the catalyst during the reaction. The rate of decomposition of $H_2O_2$ under various conditions indicated that the reaction proceeds through the catalytic participation of $Fe(III){\cdot}DDHB$. Yield of the hydroxylation products under various conditions revealed that $Fe(III){\cdot}DDHB$ is not inactivated during the reaction.

• Journal of Industrial and Engineering Chemistry
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• v.68
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• pp.380-386
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• 2018

A sustainable method was developed for the upgrade of biomass derived vanillin (a typical model compound of lignin) into the potential liquid biofuels over a layered double hydroxide supported Pd catalyst (abbreviated as CoAl-LDH/Pd). The CoAl-LDH/Pd catalyst showed high catalytic activity towards the hydrodeoxygenation of vanillin into 2-methoxy-4-methylphenol (MMP) under mild conditions in aqueous media. High MMP yield up to 86% was produced at $120^{\circ}C$ after 4 h. Kinetic studies revealed that the rate-determining step for the hydrodeoxygenation of vanillin was the hydrogenolysis of vanillyl alcohol. More importantly, the CoAl-LDH/Pd catalyst was highly stable without the loss of activity.

• Bulletin of the Korean Chemical Society
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• v.20 no.9
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• pp.993-998
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• 1999

The concurrent production of methanol and dimethyl ether from carbon dioxide hydrogenation has been studied under various reaction conditions. First, the methanol synthesis was compared with the concurrent production method. For the methanol synthesis, the ternary mixed oxide catalyst (CuO/ZnO/Al2O3) was used and for the coproduction of methanol and dimethyl ether, silica-alumina was mixed with the methanol synthesis catalyst to be a hybrid catalyst. The results show that the co-production provides much higher per-pass yield than methanol synthesis even at very short contact time. The effects of temperature, contact time, pressure and catalyst hybrid ratio on the product yields and selectivities were also determined in the co-production.

• Journal of the Semiconductor & Display Technology
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• v.9 no.3
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• pp.75-78
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• 2010

In this study we investigated the electrical properties of ZnO-based MOS capacitor with $HfO_2$ as the gate dielectric. MIM capacitor, which uses either $HfO_2$ or $Al_2O_3$ as the dielectric layer, is also studied to understand the dependency of the dielectrics on the preparation conditions. It was found that thinner $HfO_2$ films yield better electrical properties, namely lower leakage current and higher breakdown electric field. These properties were observed to deteriorate when subsequently annealed. Capacitance in the depletion region of MOS capacitor was found to increase with UV ozone treatment time up to 60min. However, when the treatment time was extended to 120min, the trend is reversed. The 'threshold voltage' was also observed to positively shift with UV ozone treatment time up to 60min. The shift apparently saturated for longer treatment.

• Journal of Hydrogen and New Energy
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• v.32 no.6
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• pp.534-541
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• 2021

In this study, a novel microwave-matrix reformer was proposed to convert CH₄, which is a major component, to a high quality hydrogen energy. And to identify this performance, it was investigated for O₂/C ratio, steam feed amount and reformed gas recirculation which are affected for methane conversion and product gas yield. Through the parametric screening studies, optimal operating conditions were that O₂/C ratio, steam feed amount and recirculation rate were 1.1, 10 mL/min and 30 L/min. In this conditions, CH₄ conversion was 68.1%, H₂ selectivity 77.2 and H₂/CO ratio 2.62 which are possible applying SOFC stack for RPG (residential power generator).

• The Korean Journal of Mycology
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• v.49 no.4
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• pp.525-530
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• 2021

The cultivation in sawdust media, mushroom productivity, and fruiting body characteristics of Lentinula edodes strains NIFoS 2778 and NIFoS 3363 were compared according to the inoculation conditions. The cultivation period was 5% shorter when liquid spawn was used. Fruiting bodies were induced after 113 days of incubation on media inoculated with liquid spawn, and the cultivation period was 119 days on media inoculated with solid spawn. Mushroom productivity of NIFoS 2778 was the highest (661.4 g) when 36 mL of liquid spawn was used. For NIFoS 3363, mushroom production was higher under liquid inoculation conditions when the same amount of liquid and solid spawns were used. The mushroom characteristics of the two strains were not significantly different, except for gill width and stipe diameter.

• Animal Bioscience
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• v.36 no.4
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• pp.540-554
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• 2023

Heat stress is a major challenge to animal production in tropical and subtropical climates. Rabbits suffer from heat stress more than farm animals because they have few sweat glands, and their bodies are covered with thick fur. Intensive farming relies on antibiotics as antimicrobials or growth promoters to increase animals' productivity and health. However, the European Union and many countries have banned or restricted the use of antibiotics in animal feed for human health concerns. Several studies have found that replacing antibiotics in rabbit feed with natural plants or feed additives increases productivity and improves immune capacity, especially under heat stress conditions. Growth performance, immune response, gut microflora, and carcass yield may be increased in rabbits fed a diet supplemented with some natural plants and/or propolis. In this review article, we discuss and summarize the effects of some herbs and plant extracts as alternative feed additives on rabbit productivity, especially for those raised under hot ambient temperatures.