• 대한금속재료학회지
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• 제47권12호
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• pp.787-796
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• 2009

The fracture toughness improvement of Ni-Mn-Ga-Fe ferromagnetic shape memory alloys containing ductile particles was explained by direct observation of microfracture processes using an in situ loading stage installed inside a scanning electron microscope (SEM) chamber. The Ni-Mn-Ga-Fe alloys contained a considerable amount of ductile particles in the grains after the homogenization treatment at $800{\sim}1100^{\circ}C$. ${\gamma}$ particles were coarsened and distributed homogeneously along {$\beta}$ grain boundaries as well as inside {$\beta}$ grains as the homogenization temperature increased. The in situ microfracture observation results indicated that ${\gamma}$ particles effectively acted as blocking sites of crack propagation, and provided stable crack growth that could be confirmed by the R-curve analysis. This increase in fracture resistance with increasing crack length improved overall fracture properties of the alloys containing ${\gamma}$ particles.

• Asian-Australasian Journal of Animal Sciences
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• 제15권1호
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• pp.117-123
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• 2002

This study was carried out to find the difference in flavor compounds between cholesterol-reduced Cheddar cheese slurries and control sample. The cheeses were made by 3 different treatments as followings: 1) Control (no homogenization, no ${\beta}$-CD), 2) Trt A (1,000 psi milk homogenization, 1% ${\beta}$-CD) and 3) Trt B (cream separation following by 10% ${\beta}$-CD, mixed with skim milk at 1,000 psi homogenization). The cholesterol removals of the cheeses were 79.30% (Trt A) and 91.22% (Trt B). The cheese slurries made by the cheeses were aged at $32^{\circ}C$ for 3 wk. The production of short-chain fatty acids (SCFA) was significantly increased with storage time in all treatments. Total amount of SCFA was dramatically increased at 2 wk and maintained thereafter in control group. The amounts of acetone and acetaldehyde were slightly increased in control at 3 wk, however, no difference was found in others. Ethanol production was dramatically increased at 1 wk and decreased thereafter in all treatments. Based on our results, cheese slurries for Trt B showed a highest cholesterol removal rate. Although little difference was found in flavor production, lower amount of SCFA was found in Trts A and B in 2 and 3 wk. It may indicate that a certain amount of SCFA is decreased during ${\beta}$-CD treatment.

• 현장농수산연구지
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• 제23권2호
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• pp.33-41
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• 2021

The effect of homogenization treatment on the suspension stability of makgeolli was evaluated. The non-soluble solids of makgeolli that were not homogenized were precipitated at 1.0-68 mm after 10 minutes of standing and 2.0-70.5 mm after 30 minutes of standing. On the other hand, in the makgeolli homogenized with a blender for more than 20 seconds, no precipitated non-soluble solids were observed during the initial 10 minutes, and when it was left still for 30 minutes, it showed precipitation of 2.0 mm (control 58.0 mm). The makgeolli treated with a high-pressure homogenizer did not show any sedimentation until 30 minutes of standing. In the sensory evaluation, the high-pressure homogenized makgeolli had a score of 3.93, whereas non-treated had a score of 2.80, which was improved by 40% by homogenization.

• 열처리공학회지
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• 제26권2호
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• pp.72-79
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• 2013

The effects of homogenization, hot-forging, and annealing condition on microstructure and hardness of a modified STD61 hot-work tool steel were investigated. The ingot specimen had a dendritic structure consisting of bainite and martensite. Spherical VC particles of approximately 50 nm and cuboidal (V,Ti)C particles of about 100 nm were observed in the ingot specimen. After homogenization, the dendritic structure was blurred, and the difference in hardness between martensite and bainite became narrow, resulting in the more homogeneous microstructure. Needle-shaped non-equilibrium $(Fe,Cr)_3C$ particles were additionally observed in the homogenized specimen. The hot-forged specimen had bainite single phase with spherical VC, cuboidal (V,Ti)C, and needle-shaped $(Fe,Cr)_3C$ particles. After annealing at $860^{\circ}C$, the microstructures of specimens were ferrite single phase with various carbides such as VC, $(Fe,Cr)_7C_3$, and $(Fe,Cr)_{23}C_6$ because of relatively slow cooling rates. The size of carbides in annealed specimens decreased with increasing cooling rate, resulting in the increase of hardness.

• 열처리공학회지
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• 제8권3호
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• pp.197-204
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• 1995

In recent work, we reported that a hot-rolled Fe-18wt%Mn alloy exhibited high damping capacity as well as excellent mechanical properties. It was also proposed that damping capacity of the alloy was proportional to the ${\gamma}/{\varepsilon}$ boundary area. In the present study, the effects of homogenization(12hrs at $1100^{\circ}C$) and solution treatment(1hr at $1050^{\circ}C$ before air cooling) on damping capacity and mechanical properties were investigated for as-cast and heat treated Fe-18wt%Mn alloy. The specimen subjected to both homogenization and solution treatment was found to show superior damping capacity and mechanical properties to the as-cast state due to removal of segregation and increase in ${\gamma}/{\varepsilon}$ boundary area.

• 한국소성가공학회:학술대회논문집
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• 한국소성가공학회 2004년도 춘계학술대회 논문집
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• pp.127-130
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• 2004

In the recent years, lightweight components fabricated with aluminum alloys have been applied into building the automobiles. Among the several competing fabrication methods, hot forging is taken as the most reliable technique to produce suspension parts such as control arms. Generally, Al forging products have been used widely for the aircraft building with the extruded stock as a starting material. For the economical base, however, the cast stocks turn to be as the forging stocks recently after a continuously casting technique was developed to produce quite a uniform microstructure enough to use for the forging process. Even more, there is a tendency to omit the homogenization step before forging, which is considered to be an indispensable process for all kinds of Al alloy, In the present study, a series of compression test was carried out to find out how the cast structure and the following heat treatments influence the deformation behavior, that is, forging characteristic.

• 한국관광식음료학회:학술대회논문집
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• 한국관광식음료학회 2003년도 학술논문발표집
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• pp.19-35
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• 2003

This study was carried out to find a cholesterol removal rate, flavor development, and bitter amino acid productions in Cheddar cheese treated with -cyclodextrin (${\beta}-CD$): 1) Control (no homogenization, no ${\beta}--CD$), and 2) Milk treatment (1000 psi milk homogenization, 1% ${\beta}-CD$). The cholesterol removal of the cheese were 79.3%. The production of short-chain free fatty acids (FFA) increased with a ripening time in both control and milk treated cheese. The releasing quantity of short-chain FFA was higher din milk treated cheese than control at 5 and 7 mo ripening. Not much difference was found in neutral volatile compounds production between samples. In bitter-tasted amino acids, milk treatment group produced much higher than control. In sensory analysis, texture score of control Cheddar cheese significantly increased, however, that in cholesterol-reduced cheese decreased dramatically with ripening time.

• 한국축산식품학회지
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• 제33권1호
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• pp.16-23
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• 2013

This study was carried out to investigate the effect of trans-cinnamaldehyde and high pressure treatment on milk. Cinnamon oil milk was manufactured by high speed homogenization (3,000 rpm) and high pressure homogenization (500 and 2,000 bar) processing UHT milk and trans-cinnamaldehyde of various concentrations (0 to 0.1% (w/v)). Cinnamon oil milk was inoculated with Escherichia coli (6.4 Log CFU/mL) and kept at $7^{\circ}C$ for 10 d to observe the antibacterial effect. The cinnamon oil milk containing 0.05% (w/v) trans-cinnamaldehyde initially began to show an antibacterial effect and Escherichia coli completely died in cinnamon oil milk added 0.1% (w/v) trans-cinnamaldehyde on the 6th day of storage. The result of the TBA value showed that the addition of 0.1% (w/v) trans-cinnamaldehyde was also effective to protect lipid oxidation. In the physical properties of cinnamon oil milk, particle sizes were enlarged in all samples during storage periods and the total color difference of cinnamon oil milk was slightly increased as level of high pressure. The surface tension of cinnamon oil milk treated 2,000 bar was remarkably higher than other samples. It seems that trans-cinnamaldehyde showed antibacterial activity and antioxidation effect at 0.05 and 0.1% (w/v) of concentration. Remarkably, high pressure treatment did not influence its microbial property but slightly affected the physical properties of cinnamon oil milk.

• KSBB Journal
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• 제25권4호
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• pp.371-378
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• 2010

For the biodiesel fuel production from microalgae, the lipid from wet and dry samples of green algae Scenedesmus sp. was extracted by using various solvents and pre-treatment methods. Extraction yield of the lyophilized sample was better than that of dry sample. Chloroform/methanol (2:1, v/v) and ultrasonication or homogenization method were also selected as the most effective solvent and pre-treatment methods for lipid extraction, respectively. Under these constraint conditions, optimization experiment of lipid extraction was investigated by Taguchi approach using orthogonal matrix $L_9$ ($3^4$) method. The optimum extraction conditions of lipid extraction was obtained at pre-treatment of homogenization, extraction time of 5 hour, temperature of $35^{\circ}C$, and solvent ratio of 1:20 (w/v). Yield of extraction at optimized condition was 20.55% and it was 96% of total lipid content (21.38%) of Scenedesmus sp.

• Nuclear Engineering and Technology
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• 제55권7호
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• pp.2474-2482
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• 2023

The development of fast reactors with complex designs and operation status requires more accurate and effective simulation. The Monte-Carlo method can generate multi-group cross-sections in arbitrary geometry without approximation on resonances treatment and leads to good results in combination with diffusion codes. However, in previous studies, the coupling of Monte-Carlo generated multi-group cross-sections (MC-MGXS) and transport solvers has shown relatively large biases in fast reactor problems. In this paper, the main contribution to the biases is proved to be the neglect of the angle-dependence of the total cross-sections. The flux-moment homogenization technique (MHT) is proposed to take into account this dependence. In this method, the angular dependence is attributed to the transfer cross-sections, keeping an independent form for the total sections. For the MET-1000 benchmark, the multi-group transport simulation results with MC-MGXS generated with MHT are improved by 700 pcm and an additional 120 pcm with higher order scattering. The factors that cause the residual bias are discussed. The core power distribution bias is also significantly reduced when MHT is used. It proves that the MCMGXS with MHT can be applicable with transport solvers in fast reactor analysis.