• Proceedings of the Korean Fiber Society Conference
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• 2001.10a
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• pp.211-214
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• 2001

최근 입자를 이용한 색전술의 재료로서 광범위하게 사용되는 폴리비닐알코올(poly (vinyl alcohol) (PVA)) 입자는 전형적인 혼성배열(atactic)이다[1]. 제조된 PVA 입자가 고내구성 및 혈액내에서 안정성을 나타내기 위해서는 중합된 PVA 입자의 분자량 뿐만 아니라 교대배열성(syndiotacticity)도 커야 한다. 교대배열기(sydiotactic group)를 풍부하게 함유하고 있는 고분자량의 PVA를 제조하기 위해서는 고분자량의 교대배열성 전구체가 얻어지도록 입체장애를 일으키는 에스테르기를 보유하고 있는 단량체를 사용하거나 중합방법을 개선하는 것이 필요하다. (중략)

• Composites Research
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• v.33 no.6
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• pp.341-345
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• 2020

We propose a measurement method for evaluating constituent contents of carbon fiber/epoxy composites through a thermogravimetric analyzer (TGA). The sample used in the test was taken from a strand specimen made of carbon fiber/epoxy tow prepreg, and the change in weight of the sample over time was measured in real time. Using a field emission scanning electron microscope (FE-SEM), we examine the thermal damage condition of the carbon fiber depending on whether resin was removed or not. We find that it was possible to test even a small amount of sample when using TGA vis-à-vis using a conventional muffle furnace. In addition, TGA enables the temperature and exposure time to be controlled, allowing the constituent contents of composite materials to be efficiently and quantitatively evaluated.

• Composites Research
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• v.17 no.3
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• pp.45-50
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• 2004

The dynamic properties of short-fiber reinforced chloroprene rubber with different interphase conditions and fiber contents have been studied as functions of frequency, amplitude and temperature. The loss factor(LF) slightly increased more than 1.33% of strain and the dynamic ratio(DR) rapidly decreased with increasing strain amplitude. The LF rapidly decreased with increasing frequency especially more than 50Hz. The DR showed the lower when it compared to virgin material with increasing frequency. The LF showed the maximum at $65^{\circ}$ and rapidly decreased after that temperature. The DR showed the lower when it compared with virgin rubber with increasing temperature. Generally, the better interphase condition showed the lower LF and DR at the same testing condition. Therefore, the short-fiber reinforced rubber could have the better isolation when the frequency ratio is more than $\sqrt{2}$ compared with frequency ratio less than $\sqrt{2}$.

• Culinary science and hospitality research
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• v.8 no.3
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• pp.267-278
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• 2002

To promote the consumption of race, comparative study was performed on characteristics of wheat flour noodle mixed with brown rice flour and colored rice flour. Protein content of colored rice was higher than that of the brown rice, but lipid and ash contents were similar to those of brown rice. Colored rice flour had significantly lower peak viscosity, holding viscosity, breakdown viscosity, final viscosity and setback viscosity than those of wheat flour, while brown rice had significantly higher peak viscosity, breakdown viscosity and setback viscosity than those of colored rice flour and wheat flour. Colored rice and brown rice had 5.3~6.4% total dietary fiber, and the proportions of soluble fiber in total dietary fiber were quite low, ranging from 9.4% to 18.8%. L(brightness), a(redness) and b(yellowness) of raw noodles were measured using a colorimeter. L(brightness) and b(yellowness) values of Asian raw noodles made from colored rice and brown rice significantly decreased. Addition of colored rice flour and brown rice flour to Asian noodle reduces cutting forces of dry and cooked noodles. The cooked noodle with 10% chalheukmi waxy rice flour was the highest in the cutting force of cooked noodle. Addition of 20% chalheukini waxy rice flour and 20% brown rice flour to wheat flour was got to a relatively high score for appearance, color, texture, taste and overall eating quality from sensory evaluation of cooked noodles.

• Korean Journal of Soil Science and Fertilizer
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• v.33 no.2
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• pp.109-113
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• 2000

The purpose of this study was conducted to develop the slow-released N fertilizer(SRNF) using of waste paper cellulose. Properties of trial product was investigated. Contents of nitrogen, phosphorus, and potassium in trial product were showed 26%, 0.04 and 0.01%, respectively. The contents of Cr, Cu, Pb and Zn were showed 17.4ppm. 259ppm, 12.2ppm and 60.0ppm in the trial product, respectively. However, As and Cd was not detected. Nitrogen of SRNF could be released 60.4% within 12hr after dissolution in water. However, the releasing velocity was thereafter remarkably delayed, showing 75% after dissolution for 72hr.

• Journal of the Korean Wood Science and Technology
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• v.37 no.3
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• pp.222-230
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• 2009

This study was to investigate the effect of alkali treatment for long kenaf fiber to improve fiber surface characterics by removal of wax, lignin and hemicellulose which affect adversely for matrix union. SEM observation was also studied to check out the interface adhesion improvement by the alkali pre-treatment. From the result, interface coherence increased by 3% alkali pre-treatment and reached a maximum by 5% alkali pre-treatment. However, the 3% the bio-composites treated with 3% alkali was highest tensile and flexural strength than other.

• Korean Journal of Food Science and Technology
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• v.29 no.4
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• pp.648-656
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• 1997

Thermal treatment of soymilk residue was carried out at 140, 150, and $160^{\circ}C$ for possible use as a raw material for dietary fiber, and some physicochemical properties of the extracts were investigated. Soluble dietary fiber(SDF) content of the extracts prepared under optimal conditions was more than 30% suggesting the conversion of insoluble dietary fiber to SDF. The main sugar components of the extracts were glucose, galactose, and arabinose. Analysis of the moelcular weight distribution by high performance size exclusion chromatography revealed that the proportion of high molecular weight fraction decreased and that of middle-sized polymer increased as the extraction temperature increased. The viscosity of aqueous solution of the extracts decreased with an increase in extraction temperature, but showed no trend as pH changed. The solubility increased with extraction temperature showing the highest at $160^{\circ}C$. The extract at $140^{\circ}C$ had the biggest calcium-binding capacity, which correlated with the changes in viscosity.

• Journal of Nutrition and Health
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• v.26 no.2
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• pp.196-201
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• 1993

In this study, dietary fiber contents in vegetables and seaweeds were determined by Mongeau-Brassard method and the AOAC official method. The average total dietary fiber(TDF) contents by AOAC official method were 6% for vegetables, and 33% for seaweeds. The average ratios soluble dietary fiber (SDF) contents to TDF contents were 47% for vegetables and 57% for vegetables except bellflower root and 1.0% - 8.0% for seaweeds. TDF$\pm$error boundary values by Mongeau-Brassard method were a little higher than those by AOAC official method. But, F/Fc of all samples were lower than 1.0. Therefore, Mongeau-Brassard method was evaluated as precisely as AOAC official method.

• Proceedings of the Korean Society of Fisheries Technology Conference
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• 2003.05a
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• pp.101-102
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• 2003

갈조류의 세포막 또는 세포간물질로 함유되어 있는 다당류인 alginate는 독특한 물리화학적인 특성을 지니고 있어, 식품공업, 직물공업, 의약용, 용수처리, 도료공업등에 널리 사용되고 있으며, 또한 새로운 용도개발을 위한 연구도 많이 진행되고 있다. 식품산업에 이용되는 alginate는 주로 Na, K, NH$_4$$^{+}$, NH$_4$$^{+}$-Ca 및 Na-Ca염형태인데 이들 수용성 alginate는 분자량, Ca함량, 입자형태(구형 또는 섬유상), 입자크기, M(mannuronic acid)/G(guluronic acid)비들에 따라 다양한 물성을 나타낸다. (중략)

• Korean Journal of Food Science and Technology
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• v.37 no.5
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• pp.746-750
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• 2005

Effect of barley bran flour on bread quality was investigated. With addition of barley bran flour, crude protein and ash contents of bread increased, and color of crumb and crust became darker than control group made with pure wheat flour. Content of dietary fiber in bread made with 5% barley bran flour was twofold higher than control group. Hardness of breads increased and volume decreased in proportion to bran content. Sensory qualities of 5% barley bran flour-added group and control group were not significantly different, but decreased in 10 and 15% barley bran flour-added groups, revealing optimal content of barley bran flour to be 5%.