• Journal of the East Asian Society of Dietary Life
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• v.18 no.5
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• pp.812-821
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• 2008

The characteristics of cold-pressed sesame oil (CPSO), virgin sesame oil (VSO), commercial heat-press extracted sesame oil (CHPESO) and commercial supercritical fluid extracted sesame oil (CSFESO) were investigated. The total phenolics of CPSO, VSO, CHPESO and CSFESO were 31.27, 68.33, 60.65 and 31.44 mg/100 g, respectively. Their $\gamma$-tocopherol contents were 32.82, 31.66, 29.26 and 26.87 mg/100g, respectively. The sesamol, sesamin, and sesamolin contents of VSO were the highest. The oxidation induction period (4.53 hr) of CPSO was lower than that of VSO, CHPESO and CSFESO (19.90, 16.50, and 12.23 hr, respectively). CPSO was rapidly oxidized during storage at $60^{\circ}C$ in the dark, and its peroxide value (POV) was increased about 14 times. Although there were few differences in electron-donating abilities at low concentrations (below 100 mg%), VSO showed the highest electron-donating abilities at higher concentrations (77.76% at 10,000 mg%). Contents of linolenic acid and oleic acid were $40.35{\sim}43.98$ and $31.59{\sim}33.46\;g$/100 g, respectively. CPSO contained the highest amount of oleic and linoleic acid among the variously extracted sesame oil.

• The Korean Journal of Food And Nutrition
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• v.36 no.6
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• pp.479-488
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• 2023

In this study, quality properties of rapeseed oil by different roasting temperatures (140, 160, 180, and 200℃) were investigated. Roasted-pressed oil (RPO) showed a decrease in lightness and an increase in redness and yellowness with an increase in temperature compared to cold-pressed oil (CPO). In addition, the β-carotene and tocopherol content also increased in RPO as the roasting temperature increased. The tocopherol content increased by 18~20% in RPO at 200℃ compared to CPO. This increase in bioactive components led to improved radical scavenging activity dependent on roasting temperature, and RPO at 200℃ showed a 2.7-fold improvement compared to CPO. Finally, it was observed that higher roasting temperatures resulted in an extended oxidation induction period, increasing by up to 3.3 times. In conclusion, roasting is an effective method for enhancing the oil functionality of domestic rapeseed varieties. This study provides basic data for producing high-quality oil.

• Journal of Korean Society of Steel Construction
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• v.21 no.5
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• pp.515-526
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• 2009

There are three main production processes in the manufacture of concrete-filled square steel columns. The first process is known as the 'box-type process' or 'four-seam method,' wherein four beams are welded together at the seams. The second is the 'cold-forming process' or 'two-seam method,' wherein the seams of two channel beams are welded together. The third is the 'pressing process' or 'one-seam method,' wherein a circular column is pressed until it becomes a square column. In calculating the production cost for the making of a steel tube, it is very important to consider the welding process to be used and the desiredthickness of the steel tube, such as a square column that was developed under a new method, formed through the four-seam flare welding method at the center of the steel column width, following the L-shape formation. Certain tests were suggested in this study to evaluate the welding amount of concrete-filled square steel columns. With the parameters of the production method of a square steel column, the thickness of the steel square columns, and the welding amount, six specimens were produced. A structural test and finite-element analysis were conducted to assess the behavior of the steel column according to the water pressure inside the steel columns.

• Journal of Animal Science and Technology
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• v.49 no.3
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• pp.387-394
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• 2007

To investigate the effects of deboning time and muscle type of ham on quality characteristics of cooked press ham, a total of twelve pigs(barrow, 100±5kg) were slaughtered and split in half. The left side ham of carcasses was deboned immediately after slaughter whereas the right side ham was deboned after chilling for 24 hours at 4℃. Each of two muscles(SM; Semimembranosus, BF; Biceps femoris) was used to make a press ham. The pH of hot-boning muscles was significantly(p＜0.05) higher than that of cold- boning muscles, and the pH of SM samples was significantly(p＜0.05) higher than BF samples. Hot-boning muscles showed significantly(p<0.05) longer sarcomere length compared with cold-boning muscles. There was no significant difference in myoglobin(Mb) percentage between SM and BF muscles, but SM samples of hot-boning showed significantly(p<0.05) lower L* value compared to hot-boning BF samples. The lightness(L*) of hot-boning muscles was significantly(p<0.05) lower than that of cold-boning muscles. These results suggested that the dark color of hot-boning samples might be due to not only the high muscle pH but also the long sarcomere length without difference in Mb percentage. Hardness and gumminess of hot-boning press ham were significantly(p<0.05) lower than those of cold-boning samples. These results implied that color and pH of press ham did not affected by deboning time or muscle type of ham. However data suggested that texture and panel test of press ham might be improved by using hot-boned muscle due to long sarcomere length of raw meat.

• Electronic Materials Letters
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• v.14 no.6
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• pp.689-699
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• 2018

Nanostructured Ni doped $Bi_2S_3$ ($Bi_{2-x}Ni_xS_3$, $0{\leq}x{\leq}0.07$) is explored as a candidate for telluride free thermoelectric material, through a combination process of mechanical alloying with subsequent consolidation by cold pressing followed with a sintering process. The cold pressing method was found to impact the thermoelectric properties in two ways: (1) introduction of the dopant atom in the interstitial sites of the crystal lattice which results in an increase in carrier concentration, and (2) introduction of a porous structure which reduces the thermal conductivity. The electrical resistivity of $Bi_2S_3$ was decreased by adding Ni atoms, which shows a minimum value of $2.35{\times}10^{-3}{\Omega}m$ at $300^{\circ}C$ for $Bi_{1.99}Ni_{0.01}S_3$ sample. The presence of porous structures gives a significant effect on reduction of thermal conductivity, by a reduction of ~ 59.6% compared to a high density $Bi_2S_3$. The thermal conductivity of $Bi_{2-x}Ni_xS_3$ ranges from 0.31 to 0.52 W/m K in the temperature range of $27^{\circ}C$ (RT) to $300^{\circ}C$ with the lowest ${\kappa}$ values of $Bi_2S_3$ compared to the previous works. A maximum ZT value of 0.13 at $300^{\circ}C$ was achieved for $Bi_{1.99}Ni_{0.01}S_3$ sample, which is about 2.6 times higher than (0.05) of $Bi_2S_3$ sample. This work show an optimization pathway to improve thermoelectric performance of $Bi_2S_3$ through Ni doping and introduction of porosity.

• Journal of the Korean Wood Science and Technology
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• v.46 no.2
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• pp.143-148
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• 2018

The aim of this research was to determine the physical and mechanical properties of glued laminated lumber (glulam) made from jabon (Anthocephalus cadamba) and pine (Pinus merkusii). Three layers of lamina from each wood species were bonded using isocyanate adhesive with a glue spread of $280g{\cdot}m^{-2}$ and then pressed using cold press with a specific pressure of 1.47 MPa. Samples had dimensions of $3cm{\times}6cm{\times}100cm$ (thickness, width, and length, respectively). Glulam properties were tested based on Japanese Agricultural Standard (JAS) 234-2003. The results showed that the density of glulam was $0.36g{\cdot}m^{-3}$ for jabon and $0.73g{\cdot}m^{-3}$ for pine. The moisture content of all glulams fulfilled the JAS standard. The mechanical properties of pine glulam fulfilled the JAS standard in all tests, whereas jabon glulam fulfilled the standard in the modulus of rupture and shear tests.

• Journal of radiological science and technology
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• v.16 no.1
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• pp.107-115
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• 1993

In this study, to develop highly sensitive radiation sensors, $CaSO_4$ : Tm phosphors and its disc-type TLD elements embedded PTFE(polytetrafluoroethylene) are fabricated. The highest sensitivity of $CaSO_4$ : Tm phosphors is obtained when phosphors have been doped with 0.5mol % Tm and sintered in atmosphere at $600^{\circ}C$ for two hours. Fabricated disc-type elements are made from a homogeneous mixture of phosphors and PTFE powder. They are first cold-pressed and then polymerized at $370^{\circ}C$ in air for one hour. The dose dependence of the prepared $CaSO_4$ : Tm TLD radiation sensors is linear within the range of $100{\mu}Gy{\sim}10Gy$ for X-rays and ${\gamma}-rays$. The response of $CaSO_4$ : Tm to 30keV X-rays is ten times higher than that of 1.25MeV $^{60}Co\;{\gamma}-rays$. The fading rate of the main peak is about 2% per a month. The spectral peaks of TL emission spectrum are at about 350nm and 475nm. The $CaSO_4$ : Tm TLD radiation sensors prepared in this work may be used as radiation dosimeter for personal and environmental monitoring because of their high sensitivity and little fading.

• Journal of the Korean Ceramic Society
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• v.22 no.6
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• pp.71-79
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• 1985

In order to fabricate the translucent electrooptic ceramics which are comparable to PLZT, $PNZT^*$ has been prepared from aqueous solutions of their itrate and chlorides. In the quarternary $Pb^{1-x} Nd_x(Zr_{0.63} Ti_{0.37})^{1-\frac{x}{4}O_3$, (PNZT) $(0.02\le x\ge 0.12)$ system cold-pressed PNZT slugs were sintered in $O_2$ in pt-crucible for 45 min. at 118$0^{\circ}C$ and were then heat-treated in air for 60 hrs. at 120$0^{\circ}C$ in Al2O3 crucibles containing $PbZrO_3$ powder to control the atmosphere. Mean particle size of calcined PNZT powders was 0.1~0.15${\mu}{\textrm}{m}$. It was found that the maximum value of optical transmission has been revealed at 6~8 at. % $Nd_2O_3$ added body and that their dielectric constant has been decreased as the frequency increased. Curic temperature has been varied inversely with $Nd^{3+}$ ion content up to 8 at. % and become constant above this value. $^*Pb_{1-x}Nd_x(Zr_{0.63} Ti_{0.37})_{1-2/4}O_3$

• Journal of the Korean Ceramic Society
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• v.30 no.6
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• pp.449-456
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• 1993

Sintering behaviour of zirconia powders prepared by different processing treatment was discussed. About >99% densities of theoretical were obtaiend on sintering at 140$0^{\circ}C$ for 2h in case of 300MPa uniaxially cold-pressed compact. But the lower densities were obtained on sintering above this temperature due to abnormal grain growth enabling the tetragonal to monoclinic phase transformation during cooling resulted in microcracks. All kinds of different dried powders exhibited nearly the same shrinkage behaviour with end-point shrinkage between 19 and 20%, and had maximum shrinkage rate (0.99~1.27%/min) around 120$0^{\circ}C$. During whole sintering process densification was mainly governed by grain growth and rearrangement of agglomerates. Heterogeneous abnormal grain growth and abrupt decrease in shrinkage were observed when continuous interagglomerate pore collapsed into isolated pores.

• Journal of the Korean Ceramic Society
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• v.31 no.7
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• pp.703-714
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• 1994

Sintering and microstructure of Ce-TZP/Al2O3 composite with $\alpha$-Al2O3 matrix containing dispersed 5~50 vol% ZrO2 were discussed. Sintered density was increased with elevating forming pressure in range of 6~300 MPa and about >99.2% of theoretical density was obtained at 1$600^{\circ}C$ for 2h in case of 300 MPa of 6~300 MPa uniaxially cold-pressed compacts containing 20 vol% ZrO2. All kinds of different batch composition exhibited nearly the same shrinkage behaviour with end-point shrinkage between 20 and 24%, and had the maximum shrinkage rate (0.41~0.54%/min) around 140$0^{\circ}C$. Grain growth was occurred faster in $\alpha$-Al2O3 than in {{{{ gamma }}-Al2O3 starting matrix during sintering at 1$600^{\circ}C$. Bimodal pore size distribution of interaglomerate pores with size of 0.03~0.2 ${\mu}{\textrm}{m}$ and of interaglomerate pores with size of around 60 ${\mu}{\textrm}{m}$ was obtained in Ce-TZP/$\alpha$-Al2O3 composite sintered at 130$0^{\circ}C$. But unimodal pore size distribution with around 0.1 ${\mu}{\textrm}{m}$ was observed in Ce-TZP/{{{{ gamma }}-Al2O3 composite sintered at the same temperature. Microcracks were occurred due to the tlongrightarrowm transformation of ZrO2 on cooling process.