• Transactions of Materials Processing
• /
• v.24 no.4
• /
• pp.241-247
• /
• 2015

In order to prevent shape defects such as fluting and stretcher strains during press forming of aged low carbon steel sheets, roller leveling conditions for reducing yield point elongation were studied. Yield point elongations of leveled sheets were determined as a function of leveling, which is defined as the plastic fraction or the ratio of plastically deformed part in sheet thickness section to the whole thickness of the sheet. By adjusting this plastic fraction during leveling to more than 78%, yield point elongation in the leveled sheets was reduced so no fluting occurred during subsequent tangential bending. Stretcher strains can be avoided by leveling the sheet to an 84% plastic fraction condition.

• Journal of Microbiology and Biotechnology
• /
• v.4 no.1
• /
• pp.56-62
• /
• 1994

A yeast strain, BT001, which can directly ferment D-xylose to ethanol was isolated from forest soils, and then identified as Candida sp. Cultural conditions for the optimum ethanol production, along with the effects of aeration on cell growth and ethanol production were investigated. Aeration stimulated the cell growth and the volumetric rate of ethanol production, but decreased the ethanol yield. Optimum temperature and initial pH for the ethanol production were $33{\circ}^C$ and 6.0, respectively. In a shake flask culture, this strain produced 52.3 g ethanol per liter from 12%(w/v) D-xylose after incubation for 96 hours. Ethanol yield was 0.436 g per g D-xylose consumed. This corresponds to 85.8% of theoretical yield. Also, this yeast strain produced ethanol from D-galactose, D-glucose and D-mannose, but not from L-arabinose and L-rhamnose. Among these sugars, D-glucose was the fastest in being converted to ethanol sugars.

• Journal of the Korean Wood Science and Technology
• /
• v.20 no.1
• /
• pp.23-27
• /
• 1992

81.9% of the cellulose delignified by acetosolv process was hydrolyzed in HCl-$AlCl_3$ hydrolysis system when $AlCl_3$ was used as catalyst in breaking down of glycosidic bond of cellulose. It was well compared that the HCl hydrolysis system without $AlCl_3$ as catalyst showed only 60~61% of the hydrolyzed yield. Also monosaccharide yield including glucose clearly increased when $AlCl_3$ was use. When concentration of HCl and $AlCl_3$ was increased, the hydrolyzed monosaccharide was increased within certain range. The monosaccharid yield out of the hydrolyzed reached 55.4% at optimum conditions which were identified as 20% of Hel solution, 0.03 Mol of $AlCl_3$, $120^{\circ}C$ of reaction temperature and 7 hours of reaction time employed in this study.

• Journal of Power System Engineering
• /
• v.20 no.3
• /
• pp.51-56
• /
• 2016

In this study, the tensile tests and hardness tests were carried out for the joints characteristics in friction stir welds of Al 5052 alloy. Three way factorial design was applied to optimal welding conditions, whose control factors were shoulder diameter, rotation speed and welding speed of tool. From the results of this study, the optimum condition for maximum yield strength was predicted as the shoulder diameter of 15 mm, welding speed of 500mm/min and rotating speed of 1000 rpm. And the presumed optimal yield strength was estimated to be $167.36{\pm}7.82MPa$ with 99% reliability. In addition the increaser rotation speed of tool and the decreaser welding speed, the decreaser the hardness at welding part.

• Proceedings of the KSME Conference
• /
• 2001.06a
• /
• pp.652-657
• /
• 2001

Densification behavior of aluminum alloy(A16061) powder was investigated under cold compaction. Experimental data were obtained under triaxial compression with various loading conditions. A special form of the Cap model was proposed from experimental data of A16061 powder under triaxial compression. The proposed yield function and several yield functions in the literature were implemented into a finite element program (ABAQUS) to compare with experimental data for densification behavior of A16061 powder under cold isostatic pressing and die compaction. The agreement between finite element calculations from the proposed yield function and experimental data is very good under cold isostatic pressing and die compaction.

• The Korean Journal of Food & Health Convergence
• /
• v.4 no.2
• /
• pp.17-23
• /
• 2018

Carica papaya is an important medicinal plant used in the management of different disease conditions. Phytochemical screening was carried out using different chemical test, Percentage yield and total phenolic content was evaluated using Folin Ciocalteu method in different solvent system; methanol, ethanol, ethyl acetate, n-butanol and n-hexane respectively. The phytochemical screening of the studies showed the presence of flavonoids, saponins, tannins, terpenoids, glycosides, steroids, carbonhydrate, anthraquinone and alkaloids. The percentage yield of crude extract and total polyphenol content was high in methanol, ethanol and ethyl acetate when compared with n-butanol and n-hexane. The studies show that Carica papaya leave extracts is a potent source of secondary metabolites. The use of the plant in the management of diseases is justified.

• Transactions of the Korean Society of Mechanical Engineers A
• /
• v.26 no.1
• /
• pp.95-104
• /
• 2002

Densification behavior of aluminum alloy(A16061) powder was investigated under cold compaction. Experimental data were obtained under triaxial compression with various loading conditions. A special form of the Cap model was proposed from experimental data of A16061 powder under triaxial compression. The proposed yield function and several yield functions in the literature were implemented into a finite element program (ABAQUS) to compare with experimental data for densifcation behavior of A16061 powder under cold isostatic pressing and die compaction. The agreement between finite element calculations from the proposed yield function and experimental data is very good under cold isostatic pressing and die compaction.

• Journal of Korea Technical Association of The Pulp and Paper Industry
• /
• v.29 no.4
• /
• pp.36-44
• /
• 1997

This experiment was mainly performed with a mechanical treatment using ultrasound. We got the following conclusions : At seven minutes-ultrasonic treatment using nonionic surfactant, yield, brightness and residual ink contents were superior to other treatment, but several strength properties were decreased. On the other hand anionic surfactant was considerably low ink removal efficiency. For ultrasonic treatment using nonionic surfactant, yield and brightness were dropped when temperature was over 4$0^{\circ}C$, but were observed to be insensitive to the pulp consistency and flotation time. In the case of nonionic surfactant, tensile and burst strength were improved when ultrasonic treatment was used comparing to non-treatment, and nonionic surfactant was generally better than anionic surfactant in terms of tensile and burst strength regardless of ultrasound conditions. Several properties were decreased when anionic surfactant was used in comparison with nonionic surfactant except yield, therefore, anionic surfactant. was not proper to be used in this condition.

• KOREAN JOURNAL OF CROP SCIENCE
• /
• v.24 no.2
• /
• pp.35-41
• /
• 1979

To observe the effects of temperature and photoperiod on the growth and yield of winter wheat (Triticum aestivum, L) eight varieties including Chang Kwang were tested at various treatments like longday-high temperature (24hrs-20\circ), shortdayhigh temperature (12hrs-20\circ), longday-low temperature (24hrs-14\circ) and shortday-low temperature (12hrs-14\circ). Among the traits measured, days to heading, plant height, spike length, number of spikes per hill and grain yield per hill were generally decreased at high temperature and long day treatment and increased at low temperature and shortday condition. Number of grains per spike was decreased at low temperature and short day condition while increased at longday and high temperature conditions. Grain weight was decreased significantly at high temperature and shortday while increased at low temperature and longday treatment.

• Journal of the Korean Society of Clothing and Textiles
• /
• v.28 no.7
• /
• pp.1029-1036
• /
• 2004

The fragrant fabrics were prepared by treatment with eucalyptus microcapsules. 100% cotton fabric, 100% polyester fabric and 100% wool fabric were used as test specimens. Using pad-dry-cure method, microcapsules were attached on each specimen by acrylic binder under conditions of varying concentration. Surface property, stiffness, and air permeability of fragrant fabrics were evaluated. As increasing concentration of binder, add-on yield was increased. Add-on yield was decreased with increasing laundering cycle, especially in polyester fabric. As the concentration of binder was increased, the properties of stiffness and air permeability were decreased. Also it fumed out that pad-dry-cure method was not suitable to polyester fabric.