• Bulletin of the Korean Chemical Society
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• v.20 no.12
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• pp.1399-1408
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• 1999

Geometrical structures for the dimerization of (NO)₂ from (NO + NO) have been calculated using ab initio Har-tree-Fock (SCF), second-order Møller-Plesset perturbation (MP2), and coupled cluster with the single, double, and triple substitution [CCSD(T)] methods with a triple zeta plus polarization (TZP) basis set including diffuse Rydberg basis functions. The structure of (NO)₂ can be described by two interactions (N…N, N…O). One is the ONNO structure with an (N…N) interaction. In this structure, acyclic cis-ONNO with $C_{2v}$-symmetry, acyclic trans-ONNO with $C_{2h}$, and cyclic ONNO with trapezoidal structure ($C_{2v}$) are optimized at the MP2 level. The other structure is the ONON structure with an (N…O) interaction. In the structure, acyclic cis-ONON with Cs$^{-symmetry}$ and cyclic ONON of the rectangular ($C_{2h}$), square $(D_{2h})$, rhombic $(D_{2h})$, and parallelogramic $(D_{2h})$ geometries are also optimized. It is found that acyclic cis-ONNO (¹A₁) is the most stable structure and cyclic ONNO (³A₁) is the least stable. Acyclic trans-ONNO (³A₁) with an (N…N) interaction, acyclic trans-ONON and bicyclic ONON $(C_{2v})$ with (N…O) interaction, and acyclic cis- and trans-NOON with an (O…O) interaction can not be optimized at the MP2 level. Particularly, acyclic trans-ONNO with $C_{2h}$-symmetry can not be optimized at the CCSD(T) level. Meanwhile, acyclic NNOO (¹A₁, $C_s)$ and trianglic NNOO (¹A₁,$C_{2v})$ formed by the (O…N) interaction between O₂ and N₂ are optimized at the MP2 level. The binding energies and the relative energy gaps among the isomers are found to be relatively small./sec. Spiral CT scans during the arterial phase were obtained 35 seconds after the injection of contrast medium. CT findings of 78 lesions less than 4cm in diameter were correlated with angiographic findings. Results : The attenuation of lesions was high(n = 69), iso(n = 5), and low(n = 4) compared with liver parenchyma during the arterial phase of spiral CT. In lesions with high-, iso-, and low-attenuation during the arterial phase of spiral CT, hypervascularity on angiograms was found in 63 of 69(91.3%), three of five(60%), and three of four lesions(75%), respectively. Six lesions with high-attenuation on the arterial phase of spiral CT were not seen on angiography. Two iso-attenuated and one low-attenuated lesion were hypovascular on angiograms. Conclusion : The results of this study suggest that with some exceptions there was good correlation between the arterial phase of spiral CT and angiography.

• Korean Journal of Soil Science and Fertilizer
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• v.48 no.5
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• pp.332-339
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• 2015

The objective of this study was to evaluate the effectiveness of different biochars on the removal of heavy metals from aqueous media. The experiment was carried out in aqueous solutions containing $200mg\;CdL^{-1}$ or $200mg\;PbL^{-1}$ using two different biochars derived from soybean stover and orange peel (20 mg Cd or $Pbg^{-1}$ biochar). After shaking for 24 hours, biochars were filtered out, and Cd and Pb in the filtrate were analyzed by flame atomic absorption spectrophotometer (FAAS). In order to provide information regarding metal binding strength on biochars, sequential extraction was performed by modified SM&T (formerly BCR). The results showed that 70~100% of initially added Cd and Pb was adsorbed on biochars and removed from aqueous solution. The removal rate of Pb (95%, 100%) was higher than that of Cd (70%, 91%). In the case of Cd, orange peel derived biochar (91%) showed higher adsorption rate than soybean stover derived biochar (70%). Cd was adsorbed on the biochar mainly in exchangeable and carbonates fraction (1st phase). In contrast, Pb was adsorbed on it mainly in the form of Fe-Mn oxides and residual fraction (2nd and 4th phase). The existence of Cd and Pb as a form of surface-precipitated complex was also observed on the surfaces of biochars detected by field emission scanning electron microscope (FESEM) and energy dispersive X-ray spectrometer (EDAX).

• Korean Chemical Engineering Research
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• v.59 no.1
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• pp.42-48
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• 2021

Zn and Al added LiNi0.85Co0.15O2 cathode materials were synthesized to improve electrochemical properties and thermal stability using a solid-state route. Crystal structure, particle size and surface shape of the synthesized cathode materials was measured using XRD (X-ray diffraction) and SEM (scanning electron microscopy). CV (cyclic voltammetry), first charge-discharge profiles, rate capability, and cycle life were measured using battery cycler (Maccor, series 4000). Strong binding energy of Al-O bond enhanced structure stability of cathode material. Electrochemical properties were improved by preventing cation mixing between Li+ and Ni2+. Large ion radius of Zn+ increased lattice parameter of NC cathode material, which meant unit-cell volume was expanded. NCZA25 showed 80% of capacity retention at 0.5 C-rate during 100 cycles, which was 12% higher than that of NC cathode. The discharge capacity of NCZA25 showed 104 mAh/g at 5 C-rate. NCZA25 achieved 36 mAh/g more capacity than that of NC cathod. NCZA25 cathode material showed excellent rate capability and cycling performance.

• Animal Bioscience
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• v.35 no.7
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• pp.1010-1020
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• 2022

Objective: The experiment was conducted to evaluate the effects of maternal undernutrition during late pregnancy on the expressions of genes involved in growth and development in ovine fetal perirenal brown adipose tissue (BAT). Methods: Eighteen ewes with singleton fetuses were allocated to three groups at day 90 of pregnancy: restricted group 1 (RG1, 0.33 MJ metabolisable energy [ME]/kg body weight [BW]^0.75/d, n = 6), restricted group 2 (RG2, 0.18 MJ ME/kg BW^0.75/d, n = 6), and a control group (CG, ad libitum, 0.67 MJ ME/kg BW^0.75/d, n = 6). The fetuses were removed at day 140 of pregnancy. All data were analyzed by using the analysis of variance procedure. Results: The perirenal fat weight (p = 0.0077) and perirenal fat growth rate (p = 0.0074) were reduced in RG2 compared to CG. In fetal perirenal BAT, the protein level of uncoupling protein 1 (UCP1) (p = 0.0001) was lower in RG1 and RG2 compared with CG and UCP1 mRNA expression (p = 0.0265) was decreased in RG2. The protein level of myogenic factor 5 (Myf5) was also decreased in RG2 (p = 0.0001). In addition, mRNA expressions of CyclinA (p = 0.0109), CyclinB (p = 0.0019), CyclinD (p = 0.0015), cyclin-dependent kinase 1 (CDK1) (p = 0.0001), E2F transcription factor 1 (E2F1) (p = 0.0323), E2F4 (p = 0.0101), and E2F5 (p = 0.0018) were lower in RG1 and RG2. There were decreased protein expression of peroxisome proliferator-activated receptor-γ (PPARγ) (p = 0.0043) and mRNA expression of CCAAT/enhancer-binding protein-α (C/EBPα) (p = 0.0307) in RG2 and decreased PPARγ mRNA expression (p = 0.0008) and C/EBPα protein expression (p = 0.0015) in both RG2 and RG1. Furthermore, mRNA expression of bone morphogenetic protein 4 (BMP4) (p = 0.0083) and BMP7 (p = 0.0330) decreased in RG2 and peroxisome proliferator-activated receptor co-activator-1α (PGC-1α) reduced in RG2 and RG1. Conclusion: Our observations support that repression of regulatory factors promoting differentiation and development results in the inhibition of BAT maturation in fetal perirenal fat during late pregnancy with maternal undernutrition.

• The Korea Journal of Herbology
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• v.29 no.2
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• pp.15-21
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• 2014

Objectives : The purpose of this study was to investigate inhibitory effects of steamed Polygonatum odoratum extract (POE) on differentiation and adipogenesis in 3T3-L1 adipocytes. Methods : Polygonatum odoratum (P. odoratum) extract was extracted with ethyl acetate. Total phenolic and flavonoid contents in POE were measured for antioxidant activity. The spectrophotometric method was used to determine the DPPH and ABTS radical scavenging activity and ferric-reducing antioxidant potential (FRAP). MTT assay was examined for cell toxicity, oil red O staining was performed for intracelluar adipogenesis in differentiated 3T3-L1 adipocytes. Western blot analysis for measurement of CCAAT/enhancer-binding protein ${\alpha}$ ($C/EBP{\alpha}$), peroxisome proliferator-activated receptor${\gamma}$ ($PPAR{\gamma}$) and AMP-activated protein kinase (AMPK) expressions were performed. Results : The results revealed that POE has antioxidant activities. Contents of total polyphenolics and flavonoids were $50.83{\pm}1.52$ GAE mg/100g dry weight of POE and $17.05{\pm}2.47$ RE mg/100g dry weight of POE, respectively. DPPH radical scavenging activity, and FRAP in 10 mg/ml concentration were $92.1{\pm}0.6%$, $244.8{\pm}9.0{\mu}M$ Fe(II) and ABTS inhibition in 5 mg/ml concentration was $84.8{\pm}4.1%$. Treatment of POE in adipocytes inhibited the differentiation and adipogenesis of 3T3-L1 adipocytes compared to those of vehicle control. Additionally, protein expressions of $C/EBP{\alpha}$ and $PPAR{\gamma}$, major transcription factor for the adipogenic genes, were significantly decreased compared to those of vehicle control (p<0.05). Futhermore, phosphorylation of AMPK was increased in 3T3-L1 adipocytes treated with POE compared to that of vehicle control (p<0.05). Conclusions : we demonstrate that steamed P. odoratum extract (POE) has potentiating antioxidant activities, inhibits differentiation and lipid accumulation and also induces energy expenditure in adipocytes, which may contribute to antiobesity property.

• Journal of Life Science
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• v.33 no.12
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• pp.967-977
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• 2023

Rubus crataegifolius (RC) is a traditional Asian medicinal plant belonging to the Rosaceae family. The fruits of RC are known to prevent adult diseases through antioxidants. In this study, the effects of RC extract (RCex) on obesity and nonalcoholic fatty liver disease (NAFLD) were evaluated in animal models. Twenty-eight male C57BL/6J mice were induced to become obese for 8 weeks and then the extract was orally administered for 8 weeks. RCex reduced body weight, adipose tissue, liver weight. RCex improved biochemical biomarkers including lipid metabolism (alanine aminotransferase (ALT), aspartate aminotransferase (AST), plasma triglyceride (TG), total cholesterol (TC), high-density lipoprotein (HDL) cholesterol and low-density lipoprotein (LDL) cholesterol). The activation of AMP-activated protein kinase (AMPK) reduced the expression of adipogenesis genes (liver × receptor (LXR), sterol regulatory element-binding protein-1c (SREBP-1c), fatty acid synthesis (FAS), acetyl-CoA carboxylase 1 (ACC1) and the effect of enhancing carnitine palmitoyltransferase (CPT) activity by RCex was verified. RCex also influence on plasma production of hormones (adiponectin & leptin) related on energy expenditure and metabolism. In addition, we confirmed that RCex improved glucose intolerance in HFD-induced obese rats. RCex was first demonstrated to have anti-obesity as well as anti-NAFLD effects by regulating fatty acid oxidation and fatty acid synthesis by phosphorylation of AMPK. This suggests that RCex could be a good supplement for the prevention of obesity and related NAFLD.

• Journal of Adhesion and Interface
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• v.25 no.1
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• pp.157-161
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• 2024

Amphiphilic gold nanoparticles, synthesized by the simultaneous binding of hydrophilic and hydrophobic ligands on their surfaces, find diverse applications in energy, bio, optical, electronic technologies, and various other fields. Particularly, these amphiphilic gold nanoparticles possess both hydrophilic and hydrophobic characteristics, enabling them to activate interface at the interface of immiscible fluids and form organized structures. The surface properties of gold nanoparticles play a crucial role in influencing the behaviors of amphiphilic gold nanoparticles at the interface of two fluids. Therefore, this study investigated the adsorption behaviors of gold nanoparticles at the organic solvent-water interface based on the surface characteristics of amphiphilic gold nanoparticles and the type of organic solvents. It was observed that the amount of adsorbed gold nanoparticles at the interface increased with the length of hydrocarbon chains in hydrophobic ligands and increased with shorter hydrocarbon chains in the organic solvent. Furthermore, using the Langmuir isotherm model, the study confirmed the formation of a monolayer by amphiphilic gold nanoparticles and obtained significant thermodynamic parameters simultaneously.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.17 no.4
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• pp.271-279
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• 1984

Effects of temperature and additives on the stability of actomyosin extracted from skeletal muscle of Israeli carp, Cyprinus carpio nudus, were studied by analyzing free SH-group, ATP-sensitivity and Ca-ATPase activity. The used additives were sucrose, sorbitol, Na-glutamate and L-cysteine. Furthermore, the denaturation constant($K_D$), protective effect(${\Delta}E/M$) and the other thermo-dynamic parameters on protein denaturation are systematically discussed. The actomyosin showed $4.12{\sim}4.68 mg/ml$ in protein concentration, $2.63{\sim}2.93\%$ in ribonucleic acid to the protein, $1:2.20{\sim}2.63$ in the binding ratio of myosin and actin, $4.33{\sim}5.26\%$ in fat content, 109.78 in ATP-sonsitivity, $0.159{\sim}0.201\;{\mu}M-Pi/min/mg-protein$ in Ca-ATPase activity and $3.3{\sim}3.4M/10^5$g-protein in free SH-group content. The first-order rate plots were obtained on the decrease of Ca-ATPase activity and ATP-sensitivity with an increase in temperature, while the free SH-group was increased to $60^{\circ}C$ and decreased rapidly above the temperature. The half-life of Ca-ATPase activity on the actomyosin Ca-ATPase was 280 min at $12^{\circ}C$, 125 min at $20^{\circ}C$, 55 min at $30^{\circ}C$ and 13 min at $40^{\circ}C$, and activation energy, activation enthalpy, activation entropy and free energy of the proteins at $20^{\circ}C$ wene 5,395 cal/mole, 4,814 cal/mole, -40.42 e.u. and 17,626 cal/mole, respectively. The protective effect of the additives on the actomyosin Ca-ATPase showed that the most effective material is $3\%$ sorbitol and followed in the order of $8\%$ Na-glutamate, $1\%$ sucrose and $1\%$ L-cysteine. The actomyosin was more stable at $-30^{\circ}C$ than at $0^{\circ}C$ and $-20^{\circ}C$. and when the additives were used in the low temperature storage, $8\%$ Na-glutamate was the most effective. $3\%$ sorbitol, $1\%$ sucrose and $1\%$ L-cysteine was to become lower in the order.

• Journal of the Korean Crystal Growth and Crystal Technology
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• v.11 no.4
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• pp.138-147
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• 2001

The stochiometric mixtures mixture of evaporating materials for the $ZnIn_{2}S_{4}$ single crystal thin film was prepared from horizontal furnace. To obtain the $ZnIn_{2}S_{4}$ single crystal thin film, $ZnIn_{2}S_{4}$ mixed crystal was deposited on throughly etched semi-insulting GaAs(100) in the Hot Wall Epitaxy(HWE) system. The sourceand substrate temperature were $610^{\circ}C$ and $450^{\circ}C$, respectively and the growth rate of the $ZnIn_{2}S_{4}$ single crystal thin film was about 0.5$\mu\textrm{m}$/hr. The crystalline structure of $ZnIn_{2}S_{4}$ single crystal thin film was investigated by photoluminescence and double crystal X-ray diffraction (DCXD) measurement. The carrier density and mobility of $ZnIn_{2}S_{4}$ single crystal thin film measured from Hal effect by van der Pauw method are $8.51{\times}10^{17}{\textrm}{cm}^{-3}$, 291$\textrm{cm}^2$/V.s at $293^{\circ}$K, respectively. From the photocurrent spectrum by illumination of perpendicular light on the c-axis of the $ZnIn_{2}S_{4}$ single crystal thin film, we have found that the values of spin orbit splitting $\Delta$So and the crystal filed splitting DCr were 0.0148eV and 0.1678 eV at $10^{\circ}$K, respectively. From the photoluminescence measurement of $ZnIn_{2}S_{4}$ single crystal thin film, we observed free excition($E_{X}$) typically observed only in high quality crystal and neutral donor bound exicton ($D^{\circ}$, X) having very strong peak intensity. The full width at half maximum and binding energy of neutral donor bound excition were 9meV and 26meV, respectively. The activation energy of impurity measured by Haynes rule was 130meV.

• Journal of the Korean Chemical Society
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• v.39 no.1
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• pp.66-70
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• 1995

The soil humic acid was subdivided into four subfractions by molecular weight (F1: >100.000 dalton; F2: >100.000 dalton; F3: >10.000 dalton; F4: >2.000 dalton) using MP-dual hollow fiber ultrafiltration system. The characterization using IR, 1H and 13C NMR spectroscopy, showed similar spectroscopic features of HA, demonstrating that the bulk properties of HA subfractions are very similar to one another. IR spectral data showed a decrease in polysaccharide contents and increase in carboxylate functionality as molecular weight become smaller.functions. The structure of (NO) can be described by two interactions (N${\cdot}{\cdot}{\cdot}$N, N${\cdot}{\cdot}{\cdot}$O). One is the ONNO structure with an (N${\cdot}{\cdot}{\cdot}$N) interaction. In this structure, acyclic cis-ONNO with $C_{2v}$-symmetry, acyclic trans-ONNO with $C_{2h}$, and cyclic ONNO with trapezoidal structure ($C_{2v}$) are optimized at the MP2 level. The other structure is the ONON structure with an (N${\cdot}{\cdot}{\cdot}$O) interaction. In the structure, acyclic cis-ONON with Cs$^{-symmetry}$ and cyclic ONON of the rectangular ($C_{2h}$), square $(D_{2h})$, rhombic $(D_{2h})$, and parallelogramic $(D_{2h})$ geometries are also optimized. It is found that acyclic cis-ONNO $(^1A_1$) is the most stable structure and cyclic ONNO ($^3A_1$) is the least stable. Acyclic trans-ONNO ($^3A_1$) with an (N${\cdot}{\cdot}{\cdot}$N) interaction, acyclic trans-ONON and bicyclic ONON $(C_{2v})$ with (N${\cdot}{\cdot}{\cdot}$O) interaction, and acyclic cis- and trans-NOON with an (O${\cdot}{\cdot}{\cdot}$O) interaction can not be optimized at the MP2 level. Particularly, acyclic trans-ONNO with $C_{2h}$-symmetry can not be optimized at the CCSD(T) level. Meanwhile, acyclic NNOO ($^1A_1$, $C_s)$ and trianglic NNOO ($^1A_1$,$C_{2v})$ formed by the (O${\cdot}{\cdot}{\cdot}$N) interaction between $O_2$and $N_2$are optimized at the MP2 level. The binding energies and the relative energy gaps among the isomers are found to be relatively small./sec. Spiral CT scans during the arterial phase were obtained 35 seconds after the injection of contrast medium. CT findings of 78 lesions less than 4cm in diameter were correlated with angiographic findings. Results : The attenuation of lesions was high(n = 69), iso(n = 5), and low(n = 4) compared with liver parenchyma during the arterial phase of spiral CT. In lesions with high-, iso-, and low-attenuation during the arterial phase of spiral CT, hypervascularity on angiograms was found in 63 of 69(91.3%), three of five(60%), and three of four lesions(75%), respectively. Six lesions with high-attenuation on the arterial phase of spiral CT were not seen on angiography. Two iso-attenuated and one low-attenuated lesion were hypovascular on angiograms. Conclusion : The results of this study suggest that with some exceptions there was good correlation between the arterial phase of spiral CT and angiography.