• Journal of Life Science
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• v.14 no.1
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• pp.198-203
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• 2004

This study was carried out to investigate the effect of mugwort podwer and carcass grade on the shelf-life of pork patty. Pork patty was prepared by four types such as grade B pcrk patty without mugwort powder (A patty), grade B pork patty with mugwort podwer (B patty), grade I pork patty without mugwort powder (C patty) and grade E pork patty with mugwort powder (D patty) and the residual nitrite, surface color, pH, VBN (volatile basic nitrogen), TBARS (2-thiobarbituric acid reactive substances) and total bacterial counts of the sample were determined during storage at 4$^{\circ}C$. The residual nitrite of pork patties with mugwort powder was highly decreased until storage for 2 weeks, pork patties without mugwort powder highly decreased until storage for 4 weeks, therefore addition of mugwort powder reduced residual nitrite of pork patty. The L＊ value of pork patty was the highest at early stage of storage, pork patties with mugwort powder were lower than that of pork patties without mugwort powder, and grade B pork patties were higher than that of the grade I pork patties. The a value of grade I pork patties were higher than that of grade B pork patties, and changes during storage were no significant difference. The b value of grade B pork patties were higher than that of grade I pork patties. The pH of pork patties decreased during storage. The VBN, TBARS and total bacterial counts added significantly during storage, and the addition of mugwort powder were not affected during storage.

• Steel and Composite Structures
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• v.36 no.6
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• pp.657-669
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• 2020

This study investigates the fire resistance characteristics of reactive powder concrete according to changes in the cement content per unit area, mixing ratio of metakaolin (MK), and content of polypropylene fiber. A fire test was conducted, and the resulting residual strength characteristics were investigated through flexural and compressive strength measurements, as well as condition rating classification based on visual evaluation. MK effectively reduced the initial high content of calcium hydroxide, thereby reducing the water vapor pressure generated during pyrolysis and slowing spalling. Furthermore, the pore structure and loose tissue were effective for relieving the water vapor pressure in the event of a fire.

• Journal of Powder Materials
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• v.14 no.6
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• pp.410-414
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• 2007

Carbon contamination from the binder resin is an inherent problem with the metal powder injection molding process. Residual carbon in the W-Cu compacts has a strong impact on the thermal and electric properties. In this study, uncertainty was quantified to evaluate determination of carbon in a W-15%Cu MIM body by the combustition method. For a valid generalization about this evaluation, uncertainty scheme applied even to the repeatability as well as the uncertainty sources of each analyse step and quality appraisal sources. As a result, the concentration of carbon in the W-Cu part were measured as 0.062% with expanded uncertainty of 0.003% at 95% level. This evaluation example may be useful to uncertainty evaluation for other MIM products.

• Journal of Magnetics
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• v.21 no.1
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• pp.51-56
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• 2016

The microstructure and magnetic properties of HDDR-treated powders after grain boundary diffusion process (GBDP) with Nd-Cu alloy at different temperatures have been studied. The variation of GBDP temperature had multifaceted influences on the HDDR-treated powders involving the microstructure, phase composition and magnetic performance. An enhanced coercivity of 16.9 kOe was obtained after GBDP at $700^{\circ}C$, due to the modified grain boundary with fine and continuous Nd-rich phase. However, GBDP at lower or higher temperature resulted in poor magnetic properties because of insufficient microstructural modification. Especially, the residual hydrogen induced phenomenon during GBDP strongly depended on the GBDP temperature.

• Food Science of Animal Resources
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• v.23 no.4
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• pp.285-291
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• 2003

The effects of carcass grade(B and E) and containing mugwort powder(0.3％) on the pH, volatile basic nitrogen(VBN), thiobarbituric acid reactive substances(TBARS), bacterial count and residual nitrite of the pork sausage were investigated during storage at 4$^{\circ}C$${\pm}$1 for 8 weeks. The pH value and VBN content of sausage containing mugwort powder were not significant different(p＞0.05) depending on the carcass grade as compared to sausage free of mugwort powder. The TBARS values of sausage containing mugwort powder were significantly lower than those of sausage free of mugwort powder up to 8 weeks of the chilling process. The sausage containing mugwort powder showed to have lower bacterial counts and residual nitrite contents than those free of mugwort powder depending on the carcass grade. However, those of sausage were not affected by the carcass grade.

• Journal of the Korean Society for Heat Treatment
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• v.9 no.1
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• pp.62-68
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• 1996

In order to establish making process of water atomized iron powder for powder metallurgy, effect of heat treatment condition on change of powder properties and impurities was investigated at each tempeature of $850{\sim}950^{\circ}C$. The results are as follows. Particle morphology of iron powder changed slightly from sphercial type to irregular type and the amount of fine particle decreased more and more with increasing of heat treatment time at each temperature. The flow rate and apparent desity of iron powder also decreased due to particle coalescence in order of $850^{\circ}C$, $950^{\circ}C$, $900^{\circ}C$. Those powder Properties became to decrease particularly at $900^{\circ}C$ in alpha iron region. On the other hand, residual carbon and oxygen contents in iron powder decreased extremely with increasing of heat treatment temperature and time.

• Journal of Powder Materials
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• v.14 no.3 s.62
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• pp.185-189
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• 2007

Various approaches have been proposed to increase the green density. Warm compaction method has been used for the reduction of residual stress, the improvement of magnetic properties and the higher densities. In this work, the effect of warm compaction on green density of Fe powder was investigated. After ball-milling of Fe oxide powder for 30 hours, Fe oxide powder was reduced through the hydrogen reduction process. The pure Fe powder and polymer binder were mixed by 3-D tubular mixer. And then the mixed powder was warm-compacted with various compaction pressure and binder contents. The green density of specimen was added polyvinyl binder was higher than any other specimens.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.27 no.7
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• pp.462-467
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• 2014

In this paper, we studied the magnetic composite sheets for electromagnetic wave noise absorber of quasi-microwave band by using soft magnetic FeSiCr and Fe50Ni flakes with the thickness of about $1{\mu}m$ and polymer. The magnetic hysteresis curve including saturation magnetization and residual magnetization and the complex permeability characteristics of the composite sheets were investigated to clarify the mixing effect on electromagnetic wave absorption properties. The saturation magnetization was decreased about 10% while the residual magnetization was increased about 15% and the real parts of complex permeability at below 500 MHz were increased 0.6~4 while those values at above 500 MHz were decreased 0.4~2.5 according to the change of contents of FeSiCr and Fe50Ni powders. As a result, the reflection loss can be moved to the lower frequency from 2~3 GHz to 1~1.5 GHz as the contents of Fe50Ni flaky powder into FeSiCr flaky powder was increased up to 50%.

• Proceedings of the Korean Powder Metallurgy Institute Conference
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• 2006.09a
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• pp.559-560
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• 2006

Powder forging is used for heavy-loaded parts (rings of rolling-contact bearings, gears etc.) production. Rolling contact fatigue is material property values of which characterize possibility of practical utilization of such parts. Rolling contact fatigue of some steels obtained out of prealloyed powders Astaloy CrM, Atomet 4601, Atomet 4901 and powder blends iron-carbon-nickel by hot forging is studied in the present paper. Effect of various kinds of heat and thermomechanical treatment on rolling contact fatigue is determined. Thermomechanical treatment provides optimal values of rolling contact fatigue. In this case steel structure contains up to 40% of retained metastable austenite which is transformed to martensite on trials. Thus typically crack is generated on residual pores and non-metallic inclusions instead of martensite zones in wrought steels.

• Culinary science and hospitality research
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• v.12 no.4 s.31
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• pp.131-139
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• 2006

This study carried out the standardization of processing conditions in mustard powder (MP) for quality improvement and suggested a recycling scheme of mustard oil(MO). Pungent taste in MP and MO was estimated using allylisothiocyanate (AITC) content as a marker. Recovery of crude oil from mustard seed (MS) was best by the cold pressing method. Residual AITC content at $30^{\circ}C$ pressing was 0.54% and 0.42% at $230^{\circ}C$. But residual AITC contents in MOs were 92ppm, 139ppm, respectively. The residual AITC content in MP was the highest (0.54%) when the moisture content in MP was 4.5%. The residual content of volatile oil in MP and MO showed similar results. In summary, crude oil must be removed from MS using the cold pressing method.