• KOREAN JOURNAL OF CROP SCIENCE
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• v.51 no.4
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• pp.298-302
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• 2006

A number of field experiments were conducted to assess the role of combined application of nitrogen and sulfur to increase the seed and oil yield of nonnodulating soybean (Glycine max (L) Merr.) cv. PK-416 $(V_1)$ and cv. PK-1024 $(V_2)$. Six combinations of N and S in three replicates each were used for this purpose i.e. $0\;S+23.5kg\;N\;ha^{-1}(T_1);\;0\;S+23.5+20kg\;N \;ha^{-1}(T_2);\;40\;S+23.5kg\;N\;ha^{-1}(T_3);\;40\;S+23.5+20kg\;N\;ha^{-1}(T_4);\;20+20\;S+23.5kg\;N\;ha^{-1}(T_5);\;20+20\;S+23.5+20kg\;N\;ha^l(T_6)$. Nitrate reductase (NR) and ATP-sulphurylase activities in the leaves were measured at various growth stages as the two enzymes catalyze the rate limiting steps of the assimilatory pathways of nitrate and sulphate, respectively. The activities of these enzymes were strongly correlated with seed yield. The higher seed, oil and protein yields were achieved with the treatment $T_6$ in both the cultivars due to optimization of NR activity and ATP-sulphurylase activity, as these parameters were influenced by N and S assimilation. Any variation from this combination was observed to decrease the activity of these enzymes resulting in reductions in the seed, oil and protein yield of soybean.

• Transactions of the Korean Society of Mechanical Engineers B
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• v.34 no.12
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• pp.1121-1126
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• 2010

This study is to investigate the effects of aromatics and T90 for low cetane number (CN) fuels on combustion and exhaust emissions in low-temperature diesel combustion. We use a 1.9-L common rail direct injection diesel engine at 1500 rpm and 2.6 bar BMEP. Low temperature diesel combustion was achieved via a high external EGR rate and strategic injection control. The tested fuels four sets: the aromatic content was 20% (A20) or 45% (A45) and the T90 temperature was $270^{\circ}C$ (T270) or $340^{\circ}C$ (T340) with CN 30. Given the engine operating conditions, the T90 was the stronger factor on the ignition delay time, resulting in a longer ignition delay time for higher T90 fuels. All the fuels produced nearly zero PM because of the extension of the ignition delay time induced by the low cetane number. The aromatic content was the main factor that affected the NOx and the NOx increased with the aromatic content.

• Journal of Korean Society of Environmental Engineers
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• v.29 no.3
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• pp.304-310
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• 2007

The purpose of this research was to investigate the effects of the co-treatment of municipal wastewater with microwave-irradiated excess sludge on the treatment efficiency and excess sludge production of the activated sludge process. When 250 mL of excess sludge with a MLSS concentration of approximately 2,000 mg/L was microwave-irradiated at $20^{\circ}C$ for $40\sim300$ sec by a microwave oven (2,450 MHz, 700 W), the temperature of the sludge increased at a rate of approximately $20^{\circ}C/min$ and the SCOD, TKN and T-P concentrations of the sludge showed the highest increase in the irradiation time of $40\sim130$ sec. And, the oxygen uptake rate measurement of the sludge microorganism suggested most of the microorganisms in the sludge were destroyed at an irradiation time above 130 sec(above $65^{\circ}C$). When the municipal wastewater and microwave-irradiated excess sludge was co-treated by the activated sludge process, almost no effect was observed in the pH and alkalinity of both the influent and effluent, but the influent concentrations of SS, COD, T-N and T-P increased. Even though the effluent SS, BOD and T-P concentrations showed almost no effect, the COD and TKN concentrations increased. The microbial yield coefficient decreased at a rate of 0.91 g SS/g COD removed as the irradiation ratio increased at a rate of 1 g SS/g SS-day.

• Journal of the Korean Magnetics Society
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• v.9 no.6
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• pp.312-320
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• 1999

Effect of deposition conditions on the magnetic properties of SmCo/Cr prepared by a RF magnetron sputtering method was studied. We obtained the maximum coercivity of 3.2 kOe in the sample of Cr(50 nm)/SmCo(40 nm, 50W, 20 mT)/Cr(150 nm, 100 W, 30 mT). The coercivity of the SmCo/Cr depends largely on the roughness of the Cr underlayer and the composition of SmCo. The roughness of the Cr underlayer increased with increasing the Ar pressure and thickness, and promoted the isolation of SmCo grains which resulted in an enhanced coercivity. The composition of the SmCo was changed with RF power and Ar pressure due to the mass difference between Sm and Co and the resputtering phenomena. The maximum coercivity was obtained in the composition of about 20 at.% Sm. The mechanism of magnetization reversal of the present SmCo films changed from domain wall motion to domain rotation as the RF power and the Ar pressure increase. This was though to be due to the defects, such as the roughness of Cr surface, porous column boundaries etc., which inhibit domain wall movement.

• Development and Reproduction
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• v.14 no.2
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• pp.59-63
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• 2010

This study was performed to examine the influence of water temperature on egg developmental speed for determining the required time and optimum water temperature for hatching of olive flounder Paralichthys olivaceus eggs. The fertilized eggs were collected from the naturally spawned adults in November 2007. The eggs were randomly divided into 6 groups of temperature (5, 10, 15, 20, 25 and $30^{\circ}C$) and transferred in $1{\ell}$ beaker, respectively. The fertilized eggs of the olive flounder did not hatched at $5^{\circ}C$ and $30^{\circ}C$ and hatching rates at 10, 15, 20 and $25^{\circ}C$ were 3, 12, 25 and 50%, respectively. The relationships between the water temperature (T, $^{\circ}C$) and required time (1/t, hour) from egg to each developmental stage were given as follows ; Blastula: 1/t=0.0208T-0.0951 ($r^2$=0.8593) Kupffer's vesicle: 1/t=0.0052T-0.0176 ($r^2$=0.9819) Myotome: 1/t=0.0034T-0.0172 ($r^2$=0.8508) Hatching: 1/t=0.0016T-0.0068 ($r^2$=0.9915) Biological minimum temperature in egg development was calculated to be $4.3^{\circ}C$.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.7 no.2
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• pp.120-125
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• 2006

By employing a rapid solidification method and atmospheric annealing at $450^{\circ}C-1hr$, we were able to manufacture inexpensively granular CuCo alloy ribbons with thickness of $20{\mu}m$ showing giant magnetoresistance (GMR) ratio of more than 5% at a high magnetic field of 0.5T. To verify maximum MR effect, the MR ratio, saturation magnetization, and microstructure change were investigated with Co contents between 5 and 30 at%. It was possible to obtain GMR ratios of 5.2% at 1.2T, and 3% at 0.5T, which implies an appropriate MR for industrial purpose at a Co content of $8{\sim}l4%$. MR ratio was reduced rapidly at a Co content below 5% due to superparamagnetic effect and at a Co content above 20% due to agglomeration of Co clusters. Surface oxidation during rapid solidification and atmospheric annealing did not have much affect on MR ratio. Our result implies that our economic CuCo granular alloy ribbons may be appropriate for high magnetic field sensor applications with wide content range of $8{\sim}14$ at%Co.

• Journal of applied mathematics & informatics
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• v.20 no.1_2
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• pp.255-277
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• 2006

By means of the use of a triangular norm T, the notion of T-fuzzy hyperideals in hypernear-rings is stated, and basic properties are investigated. Moreover, the notion of Noetherian hypernear-rings is introduced, and its characterization is given. At last, the properties of quotient hypernear-rings and T-fuzzy characteristic hyper ideals are discussed.

• Journal of Nutrition and Health
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• v.51 no.4
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• pp.316-322
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• 2018

Purpose: The Glycyrrhiza uralensis species (Leguminosae) as a medicinal biocompound, and one of its root components, isoliquritigenin (ISL), which is a flavonoid, has been reported to have anti-tumor activity in vitro and in vivo. However, its function in bone formation has not been studied yet. In this study, we tested the effect of Glycyrrhiza uralensis (ErLR) and baked Glycyrrhiza uralensis (EdLR) extracts on osteoblast proliferation, alkaline phosphatase (ALP) activity, and bone-related gene expression in osteoblastic MC3T3-E1 cells. Methods: MC3T3-E1 cells were cultured in various levels of ErLR (0, 5, 10, 15, $20{\mu}g/mL$), EdLR (0, 5, 10, 15, $20{\mu}g/mL$), or ISL (0, 5, 10, 15, $20{\mu}M$) in time sequences (1, 5, and 20 days). Also, isoliquritigenin (ISL) was tested for comparison to those two biocompound extracts. Results: MTT assay results showed that all three compounds (ErLR, EdLR, and ISL) increased osteoblastic-cell proliferation in a concentration-dependent manner for one day. In addition, both ErLR and EdLR compounds elevated the osteoblast proliferation for 5 or 20 days. Extracellular ALP activity was also increased as ErLR, EdLR, and ISL concentration increased at 20 days, which implies the positive effect of Glycyrrhiza species on osteoblast mineralization. The bone-related marker mRNAs were upregulated in the ErLR-treated osteoblastic MC3T3-E1 cells for 20 days. Bone-specific transcription factor Runx2 gene expression was also elevated in the ErLR- and EdLR-treated osteoblastic MC3T3-E1 cells for 20 days. Conclusion: These results demonstrated that Glycyrrhiza uralensis extracts may be useful for preventing osteoporosis by increasing cell proliferation, ALP activity, and bone-marker gene expression in osteoblastic cells.

• Journal of Forest and Environmental Science
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• v.38 no.1
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• pp.38-47
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• 2022

Hymenodictyon orixensis (Roxb.) Mabberley (locally known as Bhutum in Bangladesh) is both an ecologically and economically valuable multipurpose tree species for afforestation and reforestation programs in Bangladesh. Seed germination and seedling development study of H. orixense were conducted to find out the response to different growing medium, e.g., polybag (15×10 cm (T₀) and 20×15 cm (T₁)), sand medium in propagator house (T₂), conventional nursery bed (T₃), and root trainer (T₄) in the Nursery. Consequently, germination behavior and seedling morphological parameters of H. orixense were assessed. The results revealed that the sand medium of the propagator house (T₂) provided the highest germination % (58.57±22.30) and the highest germination energy (11.43±2.43) followed by seedlings growing in 20×15 cm polybags (T1) containing forest topsoil and cow-dung at a ratio of 3:1. Except for germination energy, germination values, and germination capacity, other seed biology parameters, particularly imbibition, germination period, germination rate, and plant survival percent in T₁, T₂, T₃, and T₄ were significantly (p<0.05) different from T₀. Each phenotypic parameter of seedlings and dry matter of shoot and root significantly differed from control except root length (p<0.992). Based on this study, Polybags of 20×15 cm size are regarded as the best medium for quality seedling development of H. orixense. The nursery bed (T₃) had the lowest germination performance and developed more inferior quality seedlings. Thereby, 20×15 cm size of polybags with conventional soil and cow-dung media is recommended for maximum germination and to grow the quality seedlings of H. orixense in the Nursery.

• Journal of Magnetics
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• v.6 no.3
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• pp.86-89
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• 2001

Microstructure modifications are investigated for annealed Co-based amorphous ribbon in vacuum and open air. X-ray diffraction (XRD) spectra for annealed sample in vacuum indicate atomic arrangements with initial nucleation of hcp-Co crystallite at 38$0^{\circ}C$ annealing temperature. However, the XRD spectra in samples with long annealing times of $t_a\geq300$ min demonstrate sharp and good developed surface crystalline hcp-, fcc- Co and $Co_2$Si phases. The giant magnetoimpedance (GMI) profile at 0.1 MHz displaying one-peak behavior in vacuum annealed samples at T = 38$0^{\circ}C$ irrespective of annealing time $t_a$ from 20 to 480 mim. For the annealed samples in an open air, the GMI profile shows two-peaks for $t_a$ = 20 min annealed sample. However, one of peaks disappears and an asymmetric GMI profile exhibits a drastic step-like change near zero field for $t_a\geq300$min. Such asymmetric GMI characteristics is related to the surface microstructures of fcc-Co, hop-Co and $Co_2$Si crystalline phases.