• Journal of the Korean Society of Food Culture
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• v.28 no.5
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• pp.502-511
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• 2013

This study evaluated the composition two popular species of edible bamboo shoots in Korea (Phyllostachyspubescens and Sinoarundinarianigra) and the effect of their abundant dietary fiber on intestinal microorganisms in healthy young women. The ranges of total moisture, crude protein, crude lipid, crude ash, and dietary fiber content were 87.190.8, 2.943.5, 0.150.39, 0.411.05, and 4.206.15% (wet weight basis), respectively. Moisture and crude ash content increased after heat treatment; however, crude protein, crude lipid, and dietary fiber content were reduced after heating. The major minerals found in bamboo shoots were potassium, phosphorous, sulfur, magnesium, and calcium. In addition, glucose and fructose were abundant free sugars, while asparagine and tyrosine were the most abundant free amino acids. Approximately 70% of the total free fatty acids found in bamboo shoots were linoleic acid and linolenic acid. The ascorbic acid content was 6.60~17.56 mg/100 g (wet weight basis), and one phenolic compound, p-hydroxy benzoic acid, was 0.10.2% (wet weight basis) and detected by HPLC analysis. The intake of bamboo shoots for seven days significantly increased viable cell counts of Lactobacillus spp. and reduced viable cell counts of Bacteriodes spp. in feces (p<0.05). In our data, bamboo shoots may be useful in the food industry as high dietary fiber ingredients.

• Food Science and Biotechnology
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• v.18 no.6
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• pp.1447-1458
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• 2009

Volatile extracts obtained from traditional Chinese-type soy sauces prepared with soybean (SSSB) and defatted soy meal (SSDSM) by solid phase microextraction (SPME) and direct solvent extraction (DSE) were analyzed by gas chromatography-mass spectrometry (GC-MS). The volatile flavor compounds and relative contents of different chemical classes detected in SSSB and SSDSM were compared for their differences. Results showed that significant differences in both constituents of volatile flavor compounds and relative contents of different chemical classes were observed for both kinds of soy sauces. A total of 152 and 131 compounds were identified in SSSB and SSDSM, respectively, and 102 volatile flavor compounds were common in both kinds of soy sauces. Moreover, relative contents of acids, aldehydes, esters, furan(one)s, miscellaneous compounds, phenols, pyrazines, pyrrol(idinon)es, and sulfur-containing compounds in both kinds of soy sauces were all significantly different.

• Food Science and Biotechnology
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• v.18 no.1
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• pp.66-72
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• 2009

An aqueous ribose-cysteine model system (initial pH 5.6) was conventionally heated to the same browning at varying temperatures ($120-180^{\circ}C$), supercritical carbon dioxide (SC-$CO_2$, 20 MPa) was also applied on the same matrices for same periods at each temperature and about 20% reduction of the absorbance at 420 nm was observed as compared with sole thermal treatment. The headspace volatiles from Maillard reaction mixtures were analyzed by solid-phase microextraction (SPME) in combination with gas chromatography and mass spectrometry (GC-MS), and predominated with sulfur containing compounds, such as thienothiophenes, polysulfur alicyclics, thiols, and disulfides. Reaction temperature exhibited complex effects on volatiles formation and those effects became further complicated by the SC-$CO_2$ treatment. The formation of noncarbonyl polysulfur heterocyclic compounds and thienothiophenes was generally favored at high temperatures. Most volatiles were inhibited in SC-$CO_2$ as compared with thermal treatment alone, however, the well-known meaty aromatic compounds, such as thiols and disulfides, were obviously enhanced.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2006.05a
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• pp.49-51
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• 2006

Ternary chalcopyrite $CuInS_2$ thin film material is very promising for photovoltaic. Power generation because of its excellent optical and semiconductor properties, $CuInS_2$ thin films were performed from S/In/Cu/SLG stacked elemental layer (SEL) method with post annealing treatment. $CuInS_2$ thin films were appeared from 0.84 to 1.27 of Cu/In composition ratio and sulfur composition ratios of $CuInS_2$ thin films fabricated. Analysis of the optical energy band gap of $CuInS_2$ value of l.5eV interior and exterior.

• Journal of Korean Society for Atmospheric Environment
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• v.18 no.E3
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• pp.165-174
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• 2002

A dual -column biofilter system with two different composts was used to investigate the macro-kinetics of dim-ethyl disulfide (DMDS) degradation. The biofilter columns were filled with compost mixtures up to one meter, The gas How rate and DMDS concentration to the biofilters were varied to study their effect on the removal characteris-tics of DMDS. It was found that the biodegradation of DMDS was governed by zero-order reaction -limited macro-kinetics for inlet DMDS concentrations between 10 and 55 ppmv. The overall average zero-order kinetic coeffi-cient for DMDS removal by compost was 0.50 ($\pm$0.1) ppm/sec for both compost mixtures studied. Variations in individual kinetic coefficients were observed due to varying environmental conditions, such as pH and temperature. The kinetic coefficients determined are specific to the system discussed in this work. During high acidity conditions in the filter beds, methyl mercaptan (MM) was observed in the gas samples collected. Appearance of MM was pro-bably due to decreased microbial activity in the lower portions of the biofilter. Considering the neutral pH range required and the presence of methyl mercaptan, it is likely that the microorganisms present in the biofilters used in this research are similar to the T. thioparus (strain E6) species.

• Journal of the Korean Society of Food Science and Nutrition
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• v.30 no.6
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• pp.1301-1304
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• 2001

Deodorizing activity of polyphenol cxidase (PPO) extracted from apples was investigated by measuring the changes of methyl mercaptan as an indicator of halitosis in human mouths. In the studies of apple extracts on deodorizing activity, the deodorizing activity was increased with the amount of apple extracts. In the cases of adding PPO to the low molecular fraction of apple extracts, the deodorizing activities were increased with the amount of the law molecular fraction of apple extracts and the reaction time of the extracts with PPO. Deodorizing activities of PPO is thought that o-quinone as an intermidiate produced by an oxidative reaction of PPO during enzymatic browning reactions may react with methyl mercaptan to form a non-volatile and sulfur-containing compound .

• Elastomers and Composites
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• v.56 no.1
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• pp.20-31
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• 2021

There is an increasing demand for the rolling resistance reduction in truck bus radial (TBR) tires in the tire industry. In TBR tires, natural rubber is used as a base polymer to prevent wear and satisfy required physical properties (cut and chip). A binary filler system (silica and carbon black) is used to balance the durability of the tire and rolling resistance performance. In this study, natural rubber (NR) compounds applied with a binary filler system were manufactured at different cure temperatures for vulcanizate structure analysis. The vulcanizate structures were categorized into carbon black bound rubber, silica silane rubber network, and chemical crosslink density by sulfur. Regardless of the cure temperature, the cross-link density per unit content of carbon black had a greater effect on the properties than silica due to affinity with NR. The relationship analysis between the mechanical, viscoelastic properties with vulcanizate structure could be a guideline for manufacturing practical TBR compounds.

• Korean Chemical Engineering Research
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• v.43 no.1
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• pp.140-145
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• 2005

The desulfurization abilities using GC/microreactor have been examined for $CuO-Fe_2O_3$ sorbents with respect to calcination temperatures of 700, 900 and $1,100^{\circ}C$. CuO was used as a main active component, $Fe_2O_3$ was used as an additive one and 25 wt% $SiO_2$ was used as a support. The desulfurization reaction temperature was $500^{\circ}C$ and the regeneration reaction temperature was $700^{\circ}C$. From the XRD results, the $CuFeO_2$ compound has been observed for the fresh sorbent calcined at $1,100^{\circ}C$ and the $CuFeS_2$ compound for the reacted sorbent calcined at $1,100^{\circ}C$. By the BET results, however any significant differences among sorbents calcined at the three different temperatures of 700, 900 and $1,100^{\circ}C$ haven't been observed. Especially CFS1 (CuO : $Fe_2O_3$ : $SiO_2$=67.5 wt% : 7.5 wt% : 25 wt%) sorbent calcined at $1,100^{\circ}C$ maintained about 10 g sulfur/100 g sorbent for 100 cycles by the cyclic test.

• Elastomers and Composites
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• v.48 no.2
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• pp.94-102
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• 2013

Characteristics of rubber mixture were evaluated in order to find the optimum mixing conditions of compounds containing silica and silane at various temperatures. With different mixing temperatures of 105, 120, 130, 140 and $160^{\circ}C$, the viscosity of the compound mixed at $105^{\circ}C$ showed a very high viscosity value. Compounds mixed the temperature range from at $120^{\circ}C$ to $140^{\circ}C$ showed lower viscosity than the compound mixed at $105^{\circ}C$. However, the difference was found to be small in those temperature ranges. On the contrary, at the mixing temperature of $160^{\circ}C$, the viscosity of compound increased again. Through the physical and dynamic observations, it was verified that at the mixing temperature below $120^{\circ}C$ only insufficient silica-silane reaction has been obtained. In addition, with the elevated mixing temperature of $160^{\circ}C$, Cross-linking occurred during mixing by the sulfur contained in coupling agent. In the temperature ranges from $120^{\circ}C$ to $140^{\circ}C$, because of the fast coupling reaction at higher temperature, it was thought to be more advantageous during reaction even though the trend of viscosity and dynamic mechanical property was not clear.

• Elastomers and Composites
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• v.42 no.1
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• pp.20-31
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• 2007

Material characteristics and lifetime evaluation are very important in design procedure to assure the safety and reliability of the rubber components. In this paper, the NBR compound was prepared by sulfur-cure system, and was used in predicting the lifetime of rubber gasket made by the compound. The accelerated material aging was investigated at different temperatures at 120, 140 and $160^{\circ}C$ and aging time from 3 hours to 600 hours at 5, 6, 7 vol %. of $H_2SO_4$ concentrations The rubber strips were placed in acid solution using pyrex g1ass tube. Both ends of pyrex g1ass tube were sealed to avoid evaporation of solution during heating at given time. The material test and accelerated acid-heat aging test were carried out to predict the useful life of NBR rubber gasket for a fuel cell stack. In order to investigate the effects of acid-heat aging on the properties of the NBR, tensile strength, elongation at break, hardness and crosslink-density were measured. The tensile strength decreases as the $H_2SO_4$ concentrations and temperature increase. Results were evaluated using Arrhenius equation.