• Korean Journal of Metals and Materials
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• v.47 no.7
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• pp.433-439
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• 2009

Ti and Ti based hydrogen storage alloys have been thought to be the third generation of alloys with a high hydrogen capacity, which makes it difficult to handle because of high reactivity. In order to solve the problem, the activation of a wide range of hysteresis of hydriding/dehydriding and without degradation of hydrogen capacity due to the hydriding/dehydriding cycle have to be improved in order to be aplied. Ti-Cr alloys have a high capacity about 0.8 wt.% in an ambient atmosphere. When the Ti-Cr alloys are added to Nb and Ta elements, they formed a laves phase in the alloy system. The Nb element was expected to make easy diffuse hydrogen in the Ti-Cr storage alloy, which was a catalytic element. In this study, the Ti-Nb-Cr ternary alloy was prepared by melt spinning. As-received specimens were characterized using XRD (X-ray Diffraction), SEM (Scanning Electron Microscopy) with EDX (Energy Dispersive X-ray) and TG/DSC (Thermo Gravimetric Analysis/Differential Scanning Calorimetry). In order to examine hydrogenation behavior, the PCI (Pressure-Composition-Isotherm) was performed at 293, 323, 373 and 423 K.

• Bulletin of the Korean Chemical Society
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• v.15 no.9
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• pp.713-718
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• 1994

Manganese-incorporated neodymium oxide systems with a variety of Mn mol% were prepared to investigate the effect of doping on the electrical properties of neodymium oxide. XRD, XPS, SEM, DSC, and TG techniques were used to analyze the specimens. The systems containing 2, 5, 8, and 10 mol% Mn were found to be solid solutions by X-ray diffraction analysis and the lattice parameters were obtained for the single-phase hexagonal structure by the Nelson-Riley method. The lattice parameters, a and c, decreased with increasing Mn mol%. Scanning electron photomicrographs of the specimens showed that the grain size decreased with increasing Mn mol%. The curves of log conductivity plotted as a function of 1/T in the temperature range from 500 to 1000$^{\circ}C$ at $PO_2$'s of $10^{-5}$ to $10^{-1}$ atm for the specimens were divided into high-and low-temperature regions with inflection points near 820-890$^{\circ}C$. The activation energies obtained from the slopes were 0.53-0.87 eV for low-temperature region and 1.40-1.91 eV for high-temperature region. The electrical conductivities increased with increasing Mn mol% and $PO_2$, indicating that all the specimens were p-type semiconductors. At $PO_2$'s below $10^{-3}$ atm, the electrical conductivity was affected by the chemisorption of oxygen molecule in the temperature range of 660 to 850$^{\circ}C$. It is suggested that electron holes generated by oxygen incorporation into the oxide are charge carriers for the electrical conduction in the high-temperature region and the system includes ionic conduction owing to the diffusion of oxygen atoms in the low-temperature region.

• Journal of the Korean Society of Food Science and Nutrition
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• v.36 no.2
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• pp.174-179
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• 2007

This study was carried out to investigate the effect of Gastrodiae elata Blume fractions on systolic blood pressure and serum lipid profiles in spontaneously hypertensive rats (SHR/NCrj) fed high fat diet. Twenty-four males SHR weighing approximately 160 g were randomly divided into four groups; A (low molecule, GR-1), B (polysaccharide, GR-2), C (protein, GR-3) fractions of G. elata Blume, respectively, and D (high fat diet as control). After orally tube feeding the fractions of G. elata Blume, there were no differences in final body weights among the treatment groups. Diet intake was somewhat high in the control group (D), but there were no significant differences in feed efficiency ratios. In terms of serum lipid profiles, total-cholesterol level was statistically higher in the control group (D) than in G. elata Blume fraction groups (p<0.05). Triglyceride levels of low molecule (A) and polysaccharide (B) groups were lower by 16% and 11%, respectively than that of the control group (D). HDL-cholesterol level was remarkably higher (p<0.05), whereas LDL-cholesterol level was significantly lower (by 25%) in the group B as compared to the control group (D). Atherogenic index (AI) of G. elata Blume fraction groups were significantly lower than in the control group (p<0.05). Reference blood pressure (RBP) showed an average of $180\sim190mmHg$ at 8 weeks old after 3 weeks on feeding high fat diet. Compared with RBP, final blood pressure of treatment groups (35 days after feeding the fractions of G. elata Blume gractions) were decreased by 1.7% (A), 5.5% (B) and 3.6% (C), respectively, but the control group (D) contrarily showed an increase of 2.6%. Especially, final systolic blood pressure of the polysaccharide group (B) was lower by 22 mmHg than that of the control group (D). From these findings, it can be suggested that polysaccharide fraction may improve blood serum lipids and should be considered as effective in lowering of blood pressure.

• The Korean Journal of Physiology and Pharmacology
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• v.4 no.2
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• pp.91-97
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• 2000

The purpose of the present study was to determine the preventive effects of combined interventional trial of fish oil treatment and exercise training on insulin resistance of skeletal muscle in high-fat fed rats. Male Wistar rats were randomly divided into chow diet (CD), high-fat diet (HF), high-fat diet with fish oil (FO), high-fat diet with exercise training (EX), and FO+EX groups. The rats in control group were fed chow diet containing, as percents of calories, 58.9% carbohydrate, 12.4% fat, and 28.7% protein. High-fat diet provided 32% energy as lard, 18% as corn oil, 27% as carbohydrate and 23% as casein. The fish oil diet had the same composition as the high fat diet except that 100 g menhaden oil was substituted for corn oil. Insulin sensitivity was assessed by in vitro glucose transport in the soleus muscle after diet treatment and treadmill running for 4 weeks. While the FO or EX only partially prevented insulin resistance on glucose transport and visceral obesity induced by high-fat diet, these interventions completely corrected hyperinsulinemia and hyperglycemia from the high-fat diet. The rats in the FO+EX showed normalized insulin action on glucose transport, plasma chemicals and visceral fat mass. Insulin-mediated glucose transport was negatively associated with total visceral fat mass (r=－0.734; p＜0.000), plasma triglyceride (r=－0.403; p＜0.05) and lepin (r=－0.583; p＜0.001) concentrations with significance. Multiple stepwise regression analysis showed that only total visceral fat mass was independently associated with insulin-mediated glucose transport (r=－0.668; p＜0.000). In conclusion, combined interventional trial of FO+EX recovered insulin resistance on glucose transport of skeletal muscle induced by high-fat diet. Visceral fat mass might be more important factor than plasma TG and leptin to induce insulin resistance on glucose transport of skeletal muscle in high-fat fed rats.

• Bulletin of the Korean Chemical Society
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• v.33 no.8
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• pp.2724-2730
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• 2012

A new heterogeneous acidic catalyst was successfully prepared by impregnation of silica (Aerosil 300) by an acidic ionic liquid, named 1-(4-sulfonic acid)butylpyridinium hydrogen sulfate [$PYC_4SO_3H$][$HSO_4$], and characterized using FT-IR spectroscopy, the $N_2$ adsorption/desorption analysis (BET), thermal analysis (TG/DTG), and X-ray diffraction (XRD) techniques. The amount of loaded acidic ionic liquid on Aerosil 300 support was determined by acid-base titration. This new solid acidic supported heterogeneous catalyst exhibits excellent activity in the synthesis of 2-aryl-2,3-dihydroquinazolin-4(1H)-ones by cyclocondensation reaction of 2-aminobenzamide with aromatic aldehydes under solvent-free conditions and the desired products were obtained in very short reaction times with high yields. This catalyst has the advantages of an easy catalyst separation from the reaction medium and lower problems of corrosion. Recycling of the catalyst and avoidance of using harmful organic solvent are other advantages of this simple procedure.

• Applied Chemistry for Engineering
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• v.10 no.7
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• pp.1008-1013
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• 1999

Mechanical properties and morphology of pectin/starch blend films depending upon the composition and plasticizer ratio were studied. Blends were prepared continuously in a twin-screw extruder. Films were prepared using a single-screw extruder with slit die. Most of the blends showed a good thermoplastic behavior, while the blends with very high ratio of pectin/starch had a poor thermoplasticity. Tensile properties of blend films were changed significantly by the amount of glycerol and relatively little by the ratio of pectin/starch. Differential scanning calorimetry(DSC) curves of wet blends showed a transition similar to glass transition temperature(Tg) at about $125^{\circ}C$. It was found by Scanning electron microscopy(SEM) study that there exists a good interfacial adhesion between pectin and starch.

• Korean Journal of Community Nutrition
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• v.4 no.2
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• pp.149-156
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• 1999

This study was due to investigate the dietary intakes, serum lipids and other hematological indices in female adolescent smokers. The subjects were 85 smokers, whose average pack-year(smoking years on the basis of one pack of cigarettes per day) was 1.26 and 87 nonsmokers who were female high school students in Seoul. An anthropometric measreument was performed and % body fat was also analyzed by the Bioelectrical Impedance Fatness Analyzer(GIF-891). Dietary intakes and food habits were examined through questionnaires and nutrient intakes were analyzed by the Computer Aided. Nutritional analysis program for professional(CAN-pro). Serum TG, HDL-cholesterol and total-cholesterol levels were measured with test kits. Serum glucose, albumin, GOT and GPT were measured by automated dry chemistry system, SPOTCHEM 4410. Hemoglobin, hematocrit, RBC, WBC and MCV were determined by Semi Automated Microcell Counter(F-520). All data were statistically analyzed by SAS PC package program. There was no significant difference in the anthropometric measurements between smokers and nonsmokers. The caloric intake in adolescent smokers tended to be higher than that of nonsmokers but the difference was not statistically significant. In addition, there was no significant difference between smokers and nonsmokers in biochemical indices. Analysis of serum lipids showed that the serum levels of total-cholesterol and LDL-cholesterol of nonsmokers were unexpectedly significantly higher(p<0.05) than those of smokers. Overall results indicate that smoking itself with short pack-year in healthy female adolescent did not seem to influence apparent health and nutritional status.

• Proceedings of the KAIS Fall Conference
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• 2010.11a
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• pp.313-317
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• 2010

Li, Zr doped mesoporous silica was synthesized in one pot and investigated for low temperature $CO_2$ adsorption. Herein CTAB and TEOS are used as structural directing agent and silica source respectively. The characteristics of the material was obtained from FT IR, XRD, SEM, TG and BET results. ICP AES results revealed the presence of lithium and zirconium. The material possesses high surface area ($962.22m^2g^{-1}$) with mono dispersed particles of about 2 nm. The maximum $CO_2$ adsorption capacity is 5 wt % (50 mg/g) of $CO_2$/g of sorbent at $25^{\circ}C$, which is regenerable at $200^{\circ}C$. This regeneration temperature of the adsorbent is lower than the reported lithium zirconium silicate powder. Until now, there is no report for the synthesis of Li, Zr doped mesoporous silica. The performance studies illustrate that Li, Zr doped mesoporous silica is tunable, regenerable, recyclable and selective sorbent and hence found to be a promising candidate for $CO_2$ adsorption.

• Korean Journal of Pharmacognosy
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• v.35 no.4 s.139
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• pp.300-308
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• 2004

This study was done to investigate the antidiabetic effect of Glechoma hederacea LINNAEUS in Streptozotocin (STZ)-induced diabetic rats. Diabetes was induced by intravenous injection of STZ at a dose of 45 mg/kg dissolved in citrate buffer. The methanol extract of Glechoma hederacea was orally administrated once a day for 6 days. The contents of serum glucose, triglyceride (TG), total cholesterol and Atherogenic Index (Al) were significantly decreased, but high density lipoprotein (HDL)-cholesterol and HDL-cholesterol/total cholesterol ratio (HTR) were significantly increased in Glechoma hederacea treated STZ-sample group compared to the those of STZ-control group. The content of hepatic lipid peroxide and activity of catalase were decreased, but content of glutathione as well as activities of glutathione-S-transferase and superoxide dismutase were increased in Glechoma hederacea treated STZ-sample group compared to the those of STZ-control group. The content of hepatic glycogen and activities of glucose-6-phosphate dehydrogenase, glucokinase were significantly increased, but activity of glucose-6-phosphatase was decreased in Glechoma hederacea treated STZ-sample group compared to the those of STZ-control group. These results indicated that methanol extract of Glechoma hederacea would have antidiabetic effect in STZ-induced diabetic rats.

• Journal of Korean Biological Nursing Science
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• v.14 no.2
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• pp.84-93
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• 2012

Purpose: This study was performed to identify the effects of dance sports programs on the parameters of health promotion (blood pressure, pulse, glucose, blood lipids, musculoskeletal pain, fatigue, self-efficacy, and depression) in rural women. Methods: A non-equivalent control group pretest-posttest experimental design was used. The study subjects were 38 women who were aged 45-78 and cultivating perilla leaves in a rural area. An experimental group (n=20) received the dance sports program from December 3rd, 2009 to June 3rd, 2010 and a control group (n=18) did not. Data was collected 3 times (before the program, 12 during and 24 weeks after the program) and were analyzed with $X^2$ test, t-test, and Repeated Measures ANOVA using SPSS/WIN 18.0. Results: For the experimental group, significant improvement was found in high density lipoprotein cholesterol (HDL-C), low density cholesterol (LDL-C), triglyceride (TG) musculoskeletal pain, fatigue, self-efficacy, and depression as compared to the control group. Conclusion: The findings of the study indicates that the dance sports program is effective on health promotion for rural women. Therefore, dance sports programs can be recommended for health promotion of rural residents.