• Nonlinear Functional Analysis and Applications
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• v.29 no.2
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• pp.333-360
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• 2024

This paper is concerned with the radial solutions of a nonlinear elliptic equation ∆_pu + |x|^𝑙₁ |u|^q₁-1 u + |x|^𝑙₂ |u|^q₂-1 u = 0, x ∈ ℝ^N, where p > 2, N ≥ 1, q₂ > q₁ ≥ 1, -p < 𝑙₂ < 𝑙₁ ≤ 0 and -N < 𝑙₂ < 𝑙₁ ≤ 0. We prove the existence of global solutions, we give their classification and we present the explicit behavior of positive solutions near the origin and infinity.

• Korean Journal of Agricultural Science
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• v.48 no.1
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• pp.73-81
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• 2021

The current study investigated how Saccharomyces cerevisiae ameliorates the adverse effects of aflatoxin on in vitro rumen fermentation. In this study, five groups (T₁: Control [basal feed]; T₂: T₁ + 300 ppb aflatoxin B1 [AFB₁] and T₃, T₄, and T₅: T₂ with 0.05, 0.1, and 0.2% of S. cerevisiae, respectively) were prepared and incubated in vitro. The results revealed that truly degradable dry matter (TDDM), gas production (GP), microbial biomass production (MBP), truly degradable organic matter (TDOM), partitioning factor (PF), total volatile fatty acids (TVFA), acetate (A), propionate (P) and butyrate (B) values in the control group (T₁) were higher (p < 0.05) than those of the AFB₁ fed group (T₂). The A : P ratio in the control group (T₁) was reduced (p < 0.05) when compared to that of the T₂ group. The TDDM, TDOM, GP, TVFA, A, P, and B values of T₃, T₄, and T₅ improved with the increasing levels of S. cerevisiae; however, the values of group T₅ were lower (p < 0.05) than that of the control. The values of MBP, A : P ratio and PF in group T₅ were statistically similar to that of the control. It was concluded that the inclusion of S. cerevisiae (0.05 to 0.20%) to the AFB₁ (300 ppb) contaminated feed partially to completely ameliorated the adverse effects of AFB₁ on the in vitro rumen fermentation parameters.

• Journal of the Korean Chemical Society
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• v.67 no.5
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• pp.333-338
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• 2023

In this study, the H₂O reaction with SiO clusters was investigated using ab initio Monte Carlo simulations and density functional theory calculations. Three chemistry models, PBE1/DGDZVP (Model 1), PBE1/DGDZVP (Si atom), and aug-cc-pVDZ (O and H atoms), (Model 2) and PBE1/aug-cc-pVDZ (Model 3), were used. The average bond lengths, as well as the relative and reaction energies, were calculated using Models 1, 2, and 3. The average bond lengths of Si-O and O-H are 1.67-1.75 Å and 0.96-0.97 Å, respectively, using Models 1, 2, and 3. The most stable structures were formed by the H transfer from an H₂O molecule except for Si₃O₃-H₂O-1 cluster. The Si₃O₃ cluster with H₂O exhibited the lowest reaction energy. In addition, the Bader charge distributions of the Si_nO_n and (SiO)_n-H₂O clusters with n = 1-7 were calculated using Model 1. We determined that the reaction sites between H₂O and the SiO clusters possessed the highest fraction of electrons.

• Korean Journal of Agricultural Science
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• v.47 no.1
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• pp.131-138
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• 2020

The aim of this study was to evaluate the effect of aflatoxin B₁ (AFB₁) on in vitro rumen fermentation at various dose levels of 0 (T₁), 100 (T₂), 200 (T₃), and 300 (T₄) ppb in a wheat straw-based buffalo diet. The results show that the truly degradable dry matter, truly degradable organic matter, gas production, microbial biomass production and partitioning factor values in the control group (T₁) were higher (p < 0.05) than those of the T₂, T₃, and T₄ groups. The total volatile fatty acids, acetate, propionate, and butyrate values in the control group (T₁) were higher (p < 0.05) than those of the T₂, T₃, and T₄ groups. The partitioning factor value in the control group (T₁) was higher (p < 0.05) than those of the T₂, T₃, and T₄ groups. The partitioning factor values of the T₂ and T₃ groups were higher (p < 0.05) than that of the T₄ group. There was no significant variation in the partitioning factor value between the T₂ and T₃ group. The acetate : propionate (A : P) ratio in the control group (T₁) was lower (p < 0.05) than those of the T₂, T₃, and T₄ groups. The A : P ratio in the T₂ group was lower (p < 0.05) than those of the T₃ and T₄ groups. It was concluded that different levels of AFB₁ contamination in feed significantly affect the in vitro rumen fermentation characteristics. Thus, these findings could help to determine the influences of AFB₁ in a wheat straw-based buffalo diet. Additionally, it is necessary to manage AFB₁ contamination in ruminants.

• Journal of the Korean Wood Science and Technology
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• v.50 no.4
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• pp.219-236
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• 2022

Wood-based nanocomposite electrode materials were synthesized for application in supercapacitors by mixing nanostructured hematite (Fe₂O₃) with highly porous activated carbon (AC) produced from the wood-waste of Pinus roxburghii. The AC was characterized using various instrumental techniques and the results showed admirable electrochemical properties, such as high surface area and reasonable porosity. Firstly, AC was tested as an electrode material for supercapacitors and it showed a specific capacitance of 59.02 Fg^-1 at a current density of 1 Ag^-1, cycle life of 84.2% after 1,000 cycles (at a current density of 3 Ag^-1), and energy density of 5.1 Wh/kg at a power density of 135 Wkg^-1. However, when the AC was composited with different ratios of Fe₂O₃ (1:1, 2:1, and 1:2), there was an overall improvement in its electrochemical performance. Among the 3 ratios, 2:1 (AC:Fe₂O₃) had the best specific capacitance of 102.42 Fg^-1 at 1 Ag^-1, cycle life of 94.4% capacitance after 1,000 cycles (at a current density of 3 Ag^-1), and energy density of 8.34 Wh/kg at a power density of 395.15 Wkg^-1 in 6 M KOH electrolyte in a 3-electrode experimental setup with a high working voltage of 1.55 V. Furthermore, when Fe₂O₃ was doubled, 1:2 (AC:Fe₂O₃), the electrochemical capacitive performance of the electrode twisted and deteriorated due to either the accumulation of Fe₂O₃ particles within the composite or higher bulk resistance value of pure Fe₂O₃.

• Applied Chemistry for Engineering
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• v.31 no.1
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• pp.108-114
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• 2020

In this study, NH₃-selective catalytic oxidation (SCO) efficiencies according to calcination/reduction conditions were compared when preparing various Ru[1]/TiO₂ catalysts. The Ru[1]/TiO₂ red catalyst had better NH₃ conversion and NH₃ to N₂ conversion than those of Ru[1]/TiO₂ cal. Physico-chemical properties of Ru[1]/TiO₂ catalysts were confirmed by Brunauer Emmett Teller (BET), X-ray diffraction (XRD), transmission electron microscope (TEM), X-ray photoelectron spectroscopy (XPS) and temperature programmed reduction (H₂-TPR) analyses, and the properties were shown to affect the dispersion and surface adsorption oxygen species (O_β) ratio of the active metal.

• Journal of the Korean Crystal Growth and Crystal Technology
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• v.32 no.3
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• pp.103-106
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• 2022

The effect of Al₂O₃ on isokom temperatures in soda-lime glass is estimated by comparing calculated isokom temperatures using viscosity model proposed by Lakatos. Substitution of SiO₂ with Al₂O₃ by 0.5 mol% raises the isokom temperatures by 3.1, 3.3, 3.6 and 7.2℃ at the viscosity of log η = 12.3, 10, 6.6 and 1 (Pa·s), respectively. Meanwhile, replacing 0.5 mol% of CaO with Al₂O₃ raises the isokom temperatures by 1.6, 2.3, 4.1 and 17.7℃ at the viscosity of log η = 12.3, 10, 6.6 and 1 (Pa·s), respectively.

• Journal of the Korean Ceramic Society
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• v.42 no.10 s.281
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• pp.698-702
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• 2005

Dielectric and Piezoelectric properties of complex perovskite 0.92Pb($Zr_{1/2}Ti_{1/2})O_{3}-(0.08-x)Pb(Cu_{1/3}Nb_{2/3})O_{3}-xPb(Mn_{1/3}Nb_{2/3})O_{3}(0{\leq}x{\leq}0.080$) (PZT-PCN-PMN) system were investigated as a function of PMN content. With the increase of PMN content of the sintered specimens, tetragonal phase was coexisted with rhombohedral phase, the dielectric constant was decreased, mechanical quality factor ($Q_{m}$) was inceased, and optimal sintering temperature was increased up to 1050$^{\circ}C$. For the composition of x = 0.064 sintered at 1050$^{\circ}C$ for 2 h, 1939 of maximum mechanical quality factor ($Q_{m}$), 57$\%$ of electromechanical coupling factor ($k_{p}$), and 1100$^{\circ}C$ of dielectric constant, 0.37$\% $ of dielectric loss (tan $\delta$) were obtained.

• Journal of Practical Agriculture & Fisheries Research
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• v.15 no.1
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• pp.85-93
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• 2013

This study has been conducted to investigate the effect of GA₃ solution dipping treatment after 1 days full bloom on spike growth and fruit quality at harvest of 'Campbell Early' grapevine. The fruit cluster growth(weight, length, width) and fruit stalk(diameter, length) at harvest were increased significantly by GA₃ 10 mg·L^-1 solution dipping treatment compared to control and another concentration. The berry growth (berry No, weight, length, diameter) at harvest showed no difference by treatment GA₃ concentration different. Spike weight was increased by GA₃ 5, 10, 20, mg·L^-1 treatment compared to control, but no difference GA₃ 40 mg·L^-1 treatment. The degree of compact berry, bloom, skin color and SSC at harvest by GA₃ solution dipping treatment were not significantly different from those of control. but increased seedlessness induction by GA₃ 10 mg·L^-1 treatment. The occurrence percent of berry cracking by GA₃ 5, 10, 20, 40 mg·L^-1 treatment significantly decreased. The bitter rot of berry harvest showed no difference by treatment GA₃ concentration different. Total spike length was increased by GA₃ 5, 10 mg·L^-1 treatment compared to control and GA₃ 20, 40 mg·L^-1 treatment. The spike length of 1st from 15th to position increased by GA₃ 10 mg·L^-1 treatment.

• Journal of Electrochemical Science and Technology
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• v.13 no.2
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• pp.177-185
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• 2022

Electrochemical properties of LiMn₂O₄ cathode were investigated in three types of Zn-containing electrolytes: lithium-zinc sulfate electrolyte (1M ZnSO₄ / 2M Li₂SO₄), zinc sulfate electrolyte (2MZnSO₄) and lithium-zinc-manganese sulfate electrolyte (1MZnSO₄ / 2MLi₂SO₄ / 0.1MMnSO₄). Cyclic voltammetry measurements demonstrated that LiMn₂O₄ is electrochemically inactive in pure ZnSO₄ electrolyte after initial oxidation. The effect of manganese (II) additive in the zinc-manganese sulfate electrolyte on the electrochemical performance was analyzed. The initial capacity of LiMn₂O₄ is higher in presence of MnSO₄ (140 mAh g^-1 in 1 M ZnSO₄ / 2 M Li₂SO₄ / 0.1 M MnSO₄ and 120 mAh g^-1 in 1 M ZnSO₄ / 2MLi₂SO₄). The capacity increase can be explained by the electrodeposition of MnO_x layer on the electrode surface. Structural characterization of postmortem electrodes with use of XRD and EDX analysis confirmed that partially formed in pure ZnSO₄ electrolyte Zn-containing phase leads to fast capacity fading which is probably related to blocked electroactive sites.