• KOREAN JOURNAL OF CROP SCIENCE
• /
• v.39 no.4
• /
• pp.348-352
• /
• 1994

Soybean seed consists of two major storage protein, the 7S and 11S globulins. For improving the quality of soybean seed protein, an increase of 11S/7S ratio would be a desirable objective because the 11S globulin contains much more the sulfur-containing amino acids than the 7S globulin. In this study, some soybean varieties were used to investigate the analyzing method for 7S and 11S globulins. 7S and 11S globulins couble be fractionated by their different solubilities in tris buffers. Adjusting the pH and tris concentration were major factors affecting the precipitation of the two globulins. And it was possible to screen the soybean genotypes having aberrant subunit compositions of the two globulins by an sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE) of total soybean proteins. The ratio of 11S to 7S globulin ranged from 1.29 to 1.38. This paper also dealed with the contribution of protein components in soybean seeds to the physical properties of soycurd. It indicated that the soycurd from crude 11S was remarkably harder than that from crude 7S, and springiness and cohesiveness were slightly higher in soycurd having higher proportion of 11S. So, it may concluded that proportion of protein components in soybean seed can be important factor which controls the suitability for soycurd or other foods.

• Journal of Life Science
• /
• v.11 no.6
• /
• pp.517-522
• /
• 2001

To Confirm the repression of off-odor and improvement of food quality in small black bean chungkugjang (SBC), some taste compounds of SBC added with kiwi and radish homogenate and fermented fro 3 days at 42$^{\circ}C$ were investigated. Contents of free amino acids in SBC were lower than that of soybean chungkugjang (SC) and were increased by adding kiwi and radish homogenate to black bean, indicating that two materials were effective to the enzymatic digestibility of soy protein. Of organic acids, citric acid was the most abundant, followed by acetic acid and lactic acid. Fatty acid composition was high in the order of linoleic acid (50.82~54.51%), oleic acid (17.76%~22.10%) and plamitic acid(12.13~13.79%). There were no significant difference in compositions of organic acids and fatty acids of chungkugjang. Major volatile compounds of SBC were indole , 2-5-dimethyl pyrazine and trimethyl pyrazine. Contents of alkyl pyrazines that contribute the characteristic aroma and flavor of SBC added and fermented with kiwi and radish homogenate were 3 times lower than those of SC. Uracil and UMP were major nucleic acie-drlated compounds in all four chungkugjangs. Contents of the other nucleic acid-related compounds were a similar trend in all chungkugjangs.

• Journal of The Korean Society of Grassland and Forage Science
• /
• v.42 no.4
• /
• pp.264-269
• /
• 2022

The present study investigated effects of microbial additives on the floor of Hanwoo steer manure in barn. The treatment following: without additives (CON); additives (AMA). Each treatment used 3 barns as replication and each barn contained 5 Hanwoos. The Hanwoo steer manure in barns was sub-sampled from 5 sides of pen at 0, 4 and 12 weeks. The sub-samples were used for analyses of chemical compositions, microbial counts, gas emissions and compost maturity. The concentrations of moisture, organic matter, total nitrogen and carbon-to-nitrogen (C/N ratio) of Hanwoo steer manure before the microbial additives were each 59.1%, 83.2%, 1.78% and 50.0%, respectively. The counts of lactic acid bacteria, Yeast, Bacillus subtilis, and Escherichia coli (E. coli) were each 5.94, 6.83, 7,28 and 5.52 cfu/g, but Salmonella was not detected. The ammonia-N gas was 4.67 ppm, but hydrogen sulfide gas was not detected. After 4 weeks, moisture, organic matter, total nitrogen, pH and yeast count were lowest (p<0.05). The lactic acid bacteria, yeast, Escherichia coli (E. coli) and ammonia-N gas were not effects of microbial additives. All treatments was not detected at Salmonella count and hydrogen sulfide emission, and compost maturity was completed. After 12 weeks, the lactic acid bacteria and Bacillus subtilis were highest in AMA, while moisture, yeast and E. coli were lowest (p<0.05). The ammonia-N gas was not effect by microbial additive. Salmonella and hydrogen sulfide emission were not detected in all treatments, and compost maturity was completed. Therefore, in present study, the microbial additive did not affect of gas and compost maturity, but the pathogenic microorganism such as E. coli, were inhibited by microbial additives.

• Korean Journal of Materials Research
• /
• v.33 no.8
• /
• pp.330-336
• /
• 2023

The effects of Ni²⁺ substitution for Mg²⁺-sites on the microwave dielectric properties of (Mg_1-xNi_x)(Ti_0.95(Mg_1/3Ta_2/3)_0.05)O₃ (0.01 ≤ x ≤ 0.05) (MNTMT) ceramics were investigated. MNTMT ceramics were prepared by conventional solid-state reaction. When the MgO / TiO₂ ratio was changed from 1.00 to 1.02, MgTi₂O₅ was detected as a secondary phase along with the MgTiO₃ main phase in the MNTMT specimens sintered at 1,400 ℃ for 4h. For the MNTMT specimens with MgO / TiO₂ = 1.07 sintered at 1,400 ℃ for 4h, a single phase of MgTiO₃ with an ilmenite structure was obtained from the entire range of compositions. The relative density of all the specimens sintered at 1,400 ℃ for 4h was higher than 95 %. The quality factor (Qf) of the sintered specimens depended strongly on the degree of covalency of the specimens, and the sintered specimens with x = 0.01 showed the maximum Qf value of 489,400 GHz. The dielectric constant (K) decreased with increasing Ni²⁺ content because Ni²⁺ had a lower dielectric polarizability (1.23ų) than Mg²⁺ (1.32ų). As Ni²⁺ content increased, the temperature coefficient of resonant frequency (TCF) improved, from -55.56 to -21.85 ppm/℃, due to the increase in tolerance factor (t) and the lower dielectric constant (K).

• Journal of Practical Agriculture & Fisheries Research
• /
• v.7 no.1
• /
• pp.109-117
• /
• 2005

This study was carried out to determine effects of the feeding length of spent mushroom composts from selenium-enriched mushroom (Se-SMC) on meat quality and carcass characteristics in finishing Hanwoo steers. A total of 20 steers were used in this trial with four treatments. Treatments included control (no Se-SMC), Se-SMC groups of three different feeding lengths (2, 4, and 6 months). After the completion for each feeding length, steers were slaughtered and then loin muscle (Longissimus dorsi) was sampled to evaluate meat quality characteristics. Chemical compositions of the loin, except for protein content, were not different across treatments. Protein content was highest in 6 months feeding groups, however, it was lowest in 4 months. Physical property and meat color (L*, a* and b* values) were not affected by the feeding length of Se-SMC. However, water holding capacity (WHC) for Se-SMC feeding treatments was significantly more improved (p<0.05) in comparison with the control group, showing 63.8 (2 months), 64.4 (4 months), 64.2 (6 months), and 59.5% (control), respectively. Grades for meat quality and quantity, and carcass characteristics were not affected by feeding length of Se-SMC. Our results showed that Se-SMC supplementation was not significantly associated with parameters for meat quality and carcass characteristics. However, as feeding Se-SMC lengthens, WHC for loin was more improved, suggesting that the improved WC may result in the expression of antioxidant effect.

• Resources Recycling
• /
• v.31 no.6
• /
• pp.52-59
• /
• 2022

Calcium silicate based cement (CSC) is a low-carbon cement that emits less CO₂ by up to 70% compared to ordinary Portland cement during its manufacture. Most developed countries have commercialized CSC, whereas Korea is still investigating the manufacturing characteristics and basic properties of CSC. This paper provides a review of methods for manufacturing CSC using domestic raw materials and discusses the possibility of CSC localization based on an evaluation of the basic physical properties of manufactured CSC. The experimental results of this study indicate that the primary mineral components of CSC were CS, C₃S₂ C₂S, and unreacted SiO₂. This suggests the possibility of manufacturing CSC using domestic raw materials that exhibit mineral compositions similar to that of theoretical CSC. The compressive strength of CSC mortar is less than 1MPa at the age of 7 d under wet curing. This implies that hydration does not affect the property development of CSC mortar. Meanwhile, during carbonation curing, the compressive strength is 56 MPa or higher after 7 d, which indicates excellent early strength development. Furthermore, results of Thermogravimetric Analysis Differential scanning calorimetry (TG/DSC) show that a significant amount of CaCO₃ is formed, which is consistent with the results of previous studies. This implies that carbonation is associated significantly with the properties of CSC.

• Nuclear Engineering and Technology
• /
• v.54 no.11
• /
• pp.4348-4358
• /
• 2022

The thermal-hydraulics phenomena in a containment during an accident will necessarily include radiative heat transfer (i) within the gas mixture due to the high radiative absorption and emission of steam and (ii) between the gas mixture and the surrounding structures. The analysis of some previous PANDA experiments (PSI, Switzerland) demonstrated the importance of the proper modelling of radiation for the benefit of numerical simulations. These results together with dedicated scoping calculations conducted for the present experiments indicated that the radiative heat transfer is considerable, even for a very low amount of steam (≈2%). The H2P2 series conducted in the large-scale PANDA facility at the Paul-Scherrer-Institut (PSI) in the framework of the OECD/NEA HYMERES-2 project is intended to enhance the understanding of thermal radiation phenomena and to provide a benchmark for corresponding numerical simulations. Thus, the test matrix was tailored around the two opposite extremes: either gas compositions with small steam content such that radiative heat transfer phenomena can be neglected. Or gas mixtures containing larger amounts of steam, so that radiative heat transfer is expected to play a dominant role. The H2P2 series consists of 5 experiments designed to isolate the radiation phenomena from convective and diffusive effects as much as possible. One vessel with a diameter of 4 m and a height of 8 m was preconditioned with different mixtures of air / steam at room and elevated temperatures. This was followed by the build-up of a stable helium stratification at constant pressure in the upper part of the vessel. After that, helium was injected from the top into the vessel which leads to an increase of the vessel pressure and a corresponding elevation-dependent and transient rise of the gas temperature. It is shown that even the addition of small amounts of steam in the initial gas atmosphere considerably impacts the radiative heat transport throughout all phases of the experiments and markedly influences i) the monitored gas peak temperature, ii) the temperature history during the compression and iii) the following relaxation phase after the compression was stopped. These PANDA experiments are the first of its kind conducted in a large scale thermal-hydraulic facility.

• Journal of the Korean Geotechnical Society
• /
• v.24 no.1
• /
• pp.51-59
• /
• 2008

In this study, cyclic shear characterics of sand-clay mixtures were analyzed. In order to perform cyclic triaxial tests on sand clay mixtures, natural clays with activity and silica sand were mixed variously to reproduce soils with wide range of grain size compositions. Test specimens with various fines contents were prepared by the moisture compaction and pre-consolidation methods, while paying attention to the void ratio expressed in terms of the sand structure and clay structures, and undrained cyclic shear tests were performed. In the test results, cyclic shear strength decreased with increasing of sand granular void ratio below 20% of fine contents. When the granular void ratio of the test specimen exceeded the maximum void ratio of the silica sand, the clay matrix dominated the soil structure, and soil structures were not influenced by compaction energy. It was observed that, the matrix structure of the coarse particles has great effect on the undrained cyclic shear strength characteristics for sand-clay mixtures, and therefore, it is more appropriate to pay more attention to the density of the sand structure, rather than to the fines content.

• Journal of the Korean Society of Radiology
• /
• v.17 no.2
• /
• pp.207-213
• /
• 2023

Computed tomography (CT) images are used as the basis for proton Bragg peak position estimation and treatment plan simulation. During the Hounsfield Unit (HU) based proton stopping power ratio (SPR) estimation, small differences in the patient's density and elemental composition lead to uncertainty in the Bragg peak positions along the path of the proton beam. In this study, we investigated the potential of dual-energy computed tomography image-based proton SPRs prediction accuracy to reduce the uncertainty of Bragg peak position prediction. Single- and dual-energy images of an electron density phantom (CIRS Model 062M electron density phantom, CIRS Inc., Norfolk, VA, USA) were acquired using a computed tomography system (Somatom Definition AS, Siemens Health Care, Forchheim, Germany) to estimate the SPRs of the proton beam. To validate the method, it was compared to the SPRs estimated from standard data provided by the National Institute of Standards and Technology (NIST). The results show that the dual-energy image-based method has the potential to improve accuracy in predicting the SPRs of proton beams, and it is expected that further improvements in predicting the position of the proton's Bragg peak will be possible if a wider variety of substitutes with different densities and elemental compositions of the human body are used to predict the SPRs.

• Journal of agriculture & life science
• /
• v.50 no.5
• /
• pp.153-162
• /
• 2016

This study was conducted to investigate a proper management and nutrient supply for raising replacement heifers to improve lactating performance. In order to determine a proper TDN/CP ratio that would be suitable for domestic use, 13-month-old replacement heifers were fed in the ratios of 4.6:1(T1) and 4.3:1(T2), respectively, to examine the changes in nutritional intake, digestibility, characteristics of rumen fluid and blood compositions. While dry matter intake was same at 9.0kg/day, CP intake did not show any significant difference, though T2(1.45kg/day) was slightly higher than T1(1.34kg/day). In fiber intake and digestibility, two results showed no significant difference, though T1 was slightly higher than T2. The pH, NH3-N and VFA densities in rumen fluid examined at the fourth hour after feed intake did not show any significant difference either. Overall level of VFA was not influenced largely by the TDN/CP ratio, but the iso-butyrate and iso-valerate levels and the A/P ratio were significantly high in T1(p<0.05). In blood characteristics, the treatments showed no significant difference. In conclusion, the TDN/CP ratios of 4.3:1 and 4.6:1 did not significantly affect the characteristics of the ruminant stomach, but in comparison with digestibility of 13-month-old heifers, the ratio of 4.6:1 was more appropriate for increased intake of fiber and higher digestibility.