• Bulletin of the Korean Chemical Society
• /
• v.2 no.3
• /
• pp.96-104
• /
• 1981

(1) The flow data of f (stress) and ${\dot{s}$ (strain rate) for Fe and Ti alloys were plotted in the form of f vs. -ln ${\dot{s}$ by using the literature values. (2) The plot showed two distinct patterns A and B; Pattern A is a straight line with a negative slope, and Pattern B is a curve of concave upward. (3) According to Kim and Ree's generalized theory of plastic deformation, pattern A & B belong to Case 1 and 2, respectively; in Case 1, only one kind of flow units acts in the deformation, and in Case 2, two kinds flow units act, and stress is expressed by $f={X_1f_1}+{X_2f_2}$where $f_1\;and\;f_2$ are the stresses acting on the flow units of kind 1 and 2, respectively, and $X_1,\;X_2$ are the fractions of the surface area occupied by the two kinds of flow units; $f_j=(1/{\alpha}_j) sinh^{-1}\;{\beta}_j{{\dot{s}}\;(j=1\;or\;2)$, where $1/{\alpha}_j\;and\;{\beta}_j$ are proportional to the shear modulus and relaxation time, respectively. (4) We found that grain-boundary flow units only act in the deformation of Fe and Ti alloys whereas dislocation flow units do not show any appreciable contribution. (5) The deformations of Fe and Ti alloys belong generally to pattern A (Case 1) and B (Case 2), respectively. (6) By applying the equations, f=$(1/{\alpha}_{g1}) sinh^-1({\beta}_{g1}{\dot{s}}$) and $f=(X_{g1}/{\alpha}_{g1})sinh^{-1}({\beta}_{g1}{\dot{s}})+ (X_{g2}/{\alpha}_{g2})\;shih^{-1}({\beta}_{g2}{\dot{s}})$ to the flow data of Fe and Ti alloys, the parametric values of $x_{gj}/{\alpha}_{gj}\;and\;{\beta}_{gs}(j=1\;or\;2)$ were determined, here the subscript g signifies a grain-boundary flow unit. (7) From the values of ($({\beta}_gj)^{-1}$) at different temperatures, the activation enthalpy ${\Delta}H_{gj}^{\neq}$ of deformation due to flow unit gj was determined, ($({\beta}_gj)^{-1}$) being proportional to , the jumping frequency (the rate constant) of flow unit gj. The ${\Delta}H_{gj}\;^{\neq}$ agreed very well with ${\Delta}H_{gj}\;^{\neq}$ (self-diff) of the element j whose diffusion in the sample is a critical step for the deformation as proposed by Kim-Ree's theory (Refer to Tables 3 and 4). (8) The fact, ${\Delta}H_{gj}\;^{\neq}={\Delta}H_{j}\;^{\neq}$ (self-diff), justifies the Kim-Ree theory and their method for determining activation enthalpies for deformation. (9) A linear relation between ${\beta}^{-1}$ and carbon content [C] in hot-rolled steel was observed, i.e., In ${\beta}^{-1}$ = -50.2 [C] - 40.3. This equation explains very well the experimental facts observed with regard to the deformation of hot-rolled steel..

• Elastomers and Composites
• /
• v.40 no.4
• /
• pp.277-283
• /
• 2005

LV transition curves for poly(ethylene-co-15.3 mol% octene) ($PEO_{15}$) and poly(ethylene- co-17.0 mol% octene) ($PEO_{17}$) were measured in cyclo-pentane and cyclo-hexane. Between $40{\sim}150^{\circ}C$, the LV curve for ($PEO_{15}$ + cyclo pentane) located $1.1{\sim}2.7$ bar higher than that for ($PEO_{17}$+ cyclo-pentane). In cyclo-hexane, similar behavior was observed for $PEO_{15}$ and $PEO_{17}$ solution except the pressure difference reduced to $0.9{\sim}l.6$ bar. If the backbone structure of $PEO_{15}$ were identical to that of $PEO_{17}$, the LV line for $PEO_{17}$ would locate at high pressures than that for $PEO_{15}$, since the number average molecular weight of $PEO_{17}$ (Ave. Mn=153,040) is 1.9 times higher 4han that of $PEO_{15}$ (Ave. Mn=82,200). The difference in the octene comonomer content between $PEO_{15}$ and $PEO_{17}$ is only 1.7 mole%, nevertheless this small difference in the backbone structure of the PEO greatly affected the location of the L-V curves in the mixtures comprised of PEO and cyclo-alkane.

• Nuclear Engineering and Technology
• /
• v.53 no.10
• /
• pp.3367-3378
• /
• 2021

The design phase and safety assessment of Generation IV liquid metal-cooled fast reactors calls for the improvement of fuel pin performance codes, in particular the enhancement of their predictive capabilities towards uranium-plutonium mixed oxide fuels and stainless-steel cladding under irradiation in fast reactor environments. To this end, the current capabilities of fuel performance codes must be critically assessed against experimental data from available irradiation experiments. This work is devoted to the assessment of three European fuel performance codes, namely GERMINAL, MACROS and TRANSURANUS, against the irradiation of two fuel pins selected from the SUPERFACT-1 experimental campaign. The pins are characterized by a low enrichment (~ 2 wt.%) of minor actinides (neptunium and americium) in the fuel, and by plutonium content and cladding material in line with design choices envisaged for liquid metal-cooled Generation IV reactor fuels. The predictions of the codes are compared to several experimental measurements, allowing the identification of the current code capabilities in predicting fuel restructuring, cladding deformation, redistribution of actinides and volatile fission products. The integral assessment against experimental data is complemented by a code-to-code benchmark focused on the evolution of quantities of engineering interest over time. The benchmark analysis points out the differences in the code predictions of fuel central temperature, fuel-cladding gap width, cladding outer radius, pin internal pressure and fission gas release and suggests potential modelling development paths towards an improved description of the fuel pin behaviour in fast reactor irradiation conditions.

• The Korean Journal of Food And Nutrition
• /
• v.32 no.1
• /
• pp.1-10
• /
• 2019

In order to examine the functionality of broccoli sprout (Brassica oleracea, BS), solvent extracts were prepared and their anti-oxidative and immunomodulating activities were compared with those of broccoli (B). EtOH extracts (E) were potently higher than hot-water extracts (HW) in the antioxidant contents and radical scavenging activity. In particular, the total polyphenolic contents in addition to ABTS and DPPH radical scavenging activity were significantly higher in EtOH extract of broccoli sprout (BS-E; 9.15 mg GAE/g, 4.52 mg AEAC/g, and 1.14 mg AEAC/g) compared with that of broccoli (B-E; 7.83 mg GAE/g, 3.63 mg AEAC/g, and 0.97 mg/AEAC/g). Whereas, total flavonoid content was significantly higher in B-E (1.60 mg QE/g) than BS-E (1.43 mg QE/g). Anti-inflammatory activity was investigated using LPS-induced cell line model at a concentration of $10{\sim}100{\mu}g/mL$, in which all solvent extracts of both broccoli sprouts and broccoli were not toxic to RAW 264.7 cell lines. In anti-inflammatory activity of broccoli sprouts, EtOH extracts also showed significantly more potent activity than hot-water extracts in all sample concentrations tested. In addition, BS-E ($100{\mu}g/mL$) inhibited nitric oxide (NO) and IL-6 production to 60.9% and 68.9% compared with the LPS inflammation group (without extracts), whereas B-E inhibited 49.6% and 54.9%. On the other hand, in immunostimulating activity by splenocytes and macrophages, hot-water extract showed significantly higher activity than EtOH extract. Especially, BS-HW stimulated the splenocyte proliferation (1.2-fold against saline group) and IFN-${\gamma}$ production (264.39 pg/mL) at $100{\mu}g/mL$, and the production of IL-6 (1.33-fold), IL-12 (1.09-fold) and TNF-${\alpha}$ (1.49-fold) from macrophages was also significantly enhanced over broccoli. In conclusion, broccoli sprouts showed more potent anti-oxidative, anti-inflammatory and immunostimulating activity than broccoli, suggesting the possibility of using broccoli sprouts as functional food materials.

• Journal of the Korea Convergence Society
• /
• v.12 no.8
• /
• pp.23-30
• /
• 2021

Various customizing services are also being introduced in the fashion industry in line with the diversification of consumer tastes and the demand for small production of multiple varieties. However, barriers to entry are high for consumers who are not customized, and various functions are rather complicated. This study selected the three platforms that provide the most similar services to Marple, the No. 1 fashion platform sales, as comparative models and used them as a basic study for web-based fashion customization platform design through case analysis. As a research method, theoretical examinations were conducted through literature surveys, followed by web analysis based on layout, menu, color, icon, and interaction. The study found that the placement of options, the composition of menu windows, the number of point colors, and the use of icons without functions of metaphores hindered the use of customizing platforms. This work proposes a solution, and aims to contribute to increasing the usability of future customizing web by comprehensively analyzing the visual shaping elements of web platform design.

• Journal of Mushroom
• /
• v.19 no.4
• /
• pp.322-328
• /
• 2021

This study was carried out to evaluate potential of Hypsizygus marmoreus (brown cultivar) as a functional food and drug materials. H. marmoreus were divided into pileus and stipe and extracted in hot water and 80% ethanol. The total polyphenol content was highest in the hot water extracts (pileus 17.15±0.19 mg of GAE g, stipe 7.37±0.16 mg of GAE/g) and pileus compared to the ethanol extracts (pileus 10.23±0.14 mg of GAE/g, stipe 3.76.±0.19 mg of GAE/g) and stipe. Also, hot water extracts of pileus from H. marmoreus (brown cultivar) was more effective DPPH, ABTS, ORAC value, reducing power than ethanol extracts and stipe extracts. The pileus and stipe extracts were confirmed to be non-cytotoxic in the mouse macrophage cell line RAW 264.7 determined by WST-1 (4-[3-(4-iodophenyl)-2-(4-nitrophenyl)-2H-5-tetrazolio]-1,3-benzene disulphonate) assay. Overall, extracts of H. marmoreus (brown cultivar) was higher antioxidant activity than other mushrooms, and no cytotoxicity. Therefore, H. marmoreus (brown cultivar) showed potential as a functional food and drug materials. The brown cultivar of H. marmoreus have higher antioxidant activity than white cultivar, H. marmoreus seem to have different antioxidant activity depending on the cultivar.

• KOREAN JOURNAL OF CROP SCIENCE
• /
• v.45 no.3
• /
• pp.199-202
• /
• 2000

The leaf color varies with the contents of pigments, especially chlorophylls and carotenoids. Teichung 65 (T.65), a japonica rice, with pgl(pale-green leaf) gene exhibits pale green color on the whole plant from seedling to harvest. This study conducted to evaluate the agronomic characters and examine the chloroplasts of 'pgl' plants in parents and BC$_1$F$_2$ of T.65(pgl) xSuweon ${345}^2$. The average grain yield of pale-green-leaf individuals in F$_2$ was the same as T.65(pgl) but that of green-leaf individuals was much higher than that of Suweon 345. The contents of chlorophyll a(Ca), chlorophyll b(Cb) and total chlorophyll content(Ct) of T.65(pgl) in flag leaf were lower than those of Suweon 345, but the Ca/Cb ratio of T.65(pgl) was higher than that of Suweon 345 during from 15 days after heading (DAH) to 60 DAH. The SPAD value of T.65(pgl) in flag leaf was lower than that of Suweon 345, but that in the second and the third leaves was similar to that of Suweon 345. The SPAD value of pale-green-leaf individual group was lower than that of green individual group in upper three leaves. The structural difference of chloroplasts in flag leaf between T.65(pgl) and Suweon 345 through TEM at 20 DAH was not detected, but the number of osmium granules in chloroplast of T.65(pgl) were higher than that of Suweon 345.

• Animal Bioscience
• /
• v.36 no.4
• /
• pp.629-641
• /
• 2023

Objective: This study investigated the effects of extruded flaxseed with and without herbs mixture on egg performance, yolk fatty acids (FAs), lipid components, blood biochemistry, serological enzymes, antioxidants, and immune system of Hy-Line W-36 hens for nine weeks. Methods: Two hundred forty laying hens were randomly distributed to eight treatments, resulting in six replicates with five hens. Graded levels of dietary extruded flaxseed (0, 90, 180, and 270 g/kg) with and without herbs mixture (24 g/kg: garlic, ginger, green tea, and turmeric 6 g/kg each) were designed as treatments. Results: The two-way analysis of variance indicated that hens fed herbs mixture had a higher value of egg production, yolk high-density lipoprotein (HDL), superoxide dismutase, glutathione peroxidase, and white blood cell and lower contents of yolk cholesterol, glucose, and blood low-density lipoprotein than those fed diets without herb mixtures (p<0.05). The Flx27 (270 g/kg flaxseed) (153.5 g/kg n-3 FAs) and Flx27+H (270 g/kg flaxseed plus 24 g/kg herbs mixture) (150.5 g/kg n-3 FAs) groups were the most promising treatments in terms of yolk n-3 FAs content. In-teraction effect (herbs- flaxseed) for blood cholesterol, HDL, malondialdehyde, glutaredoxin, alanine transaminase, (ALT), aspartate transaminase (AST), haemoglobin and immune parameters was significant (p<0.05). The results showed layers fed herbs mixture (Flx9+H, Flx18+H, and Flx27+H) had a better value of total antibody, immunoglobulin M, immunoglobulin G, ALT, AST, and blood HDL as compared with representative flaxseed levels without herbs. Conclusion: High inclusion levels of extruded flaxseed (270 g/kg) without herbs to enrich eggs with n-3 appears to impair the antioxidant system, immunohematological parameters, and sero-logical enzymes. Interestingly, the herbs mixture supplementation corrected those effects. Therefore, feeding layers with flaxseed-rich diets (270 g/kg) and herbs mixture can be a promising strategy to enrich eggs with n-3 FAs.

• The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
• /
• v.6 no.3
• /
• pp.152-163
• /
• 2001

Based upon the sedimentological, geochemical and micropaleontological analyses of two sediment cores from the Antarctic Peninsula (AP), three distinct lithological units can be recognized: (1) ice-proximal an/or ice-distal diamictons in the lower part of the cores, accumulated just seaward of the grounding line of the ice shlef until 11,000 yrs BP; (2) diatomaceous mud between 6,000 and 2,500 yrs BP in the middle part, resulted from a large influx of organic materials by enhanced production of open marine condition; (3) diatomaceous sandy mud since 2,500 yrs BP, characterized by an increase in sand content and decrease in TOC and diatom abundance in the lower layers, which reflects the formation of more extensive and seasonally persistent sea ice. Based on the C-14 radiocarbon dating, the sub-ice shlef deposition of the diamicton on the AP western shelf completed around 11,000 yrs BP. Colder condition was reinstated between 12,800 and 11,600 BP with a dropin TOC content and diatom abundance, which is coincident with the Younger Dryas event in the North Atlanticregion. At this time, the ice shelf, that is now absent in the study area, appears to advance as evidenced by an abrupt increase in sea-ice taxa. A climatic optimum is recognized between 9,000 and 2,500 BP, coincide witha mid-Holocene climatic optimum 'Hypsithermal Warm Period' from the other Antarctic sites. During this time, diatomaceous mud accumulated by a large influx of organic materials by enhanced production occurred in openmarine condition. Around 2,500 BP, diatomaceous sandy mud reflects the formation of more extensive and seasonally persistent sea ice, coincident with the onset of the Neoglacial in the Antarctic. Our results provide evidence of climatic change from the Antarctic Peninsula`s western shelf that helps in determining the existence and timing of Holocene milennial-scale climatic events in the Southern Hemisphere.

• Journal of Nuclear Fuel Cycle and Waste Technology(JNFCWT)
• /
• v.6 no.4
• /
• pp.307-327
• /
• 2008

Geochemical study on the rocks and minerals of the Gyeongju low and intermediate level waste repository was carried out in order to provide geochemical data for the safety assessment and geochemical modeling. Polarized microscopy, X-ray diffraction method, chemical analysis for the major and trace elements, scanning electron microscopy(SEM), and stable isotope analysis were applied. Fracture zones are locally developed with various degrees of alteration in the study area. The study area is mainly composed of granodiorite and diorite and their relation is gradational in the field. However, they could be easily distinguished by their chemical property. The granodiorite showed higher $SiO_2$ content and lower MgO and $Fe_2O_3$ contents than the diorite. Variation trends of the major elements of the granodiorite and diorite were plotted on the same line according to the increase of $SiO_2$ content suggesting that they were differentiated from the same magma. Spatial distribution of the various elements showed that the diorite region had lower $SiO_2,\;Al_2O_3,\;Na_2O\;and\;K_2O$ contents, and higher CaO, $Fe_2O_3$ contents than the granodiorite region. Especially, because the differences in the CaO and $Na_2O$ distribution were most distinct and their trends were reciprocal, the chemical variation of the plagioclase of the granitic rocks was the main parameter of the chemical variation of the host rocks in the study area. Identified fracture-filling minerals from the drill core were montmorillonite, zeolite minerals, chlorite, illite, calcite and pyrite. Especially pyrite and laumontite, which are known as indicating minerals of hydrothermal alteration, were widely distributed in the study area indicating that the study area was affected by mineralization and/or hydrothermal alteration. Sulfur isotope analysis for the pyrite and oxygen-hydrogen stable isotope analysis for the clay minerals indicated that they were originated from the magma. Therefore, it is considered that the fracture-filling minerals from the study area were affected by the hydrothermal solution as well as the simply water-rock interaction.