• Transactions of the Korean hydrogen and new energy society
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• v.35 no.2
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• pp.185-194
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• 2024

Fe-Ni nanocatalysts loaded on carbon black were prepared via spontaneous reduction reaction of iron (II) acetylacetonate and nickel (II) acetylacetonate in dry process. Their morphology and elemental analysis were characterized by scanning electron microscopy, transmission electron microscopy (TEM), and energy dispersive X-ray analyzer. The loading weight of the nanocatalysts was measured by thermogravimetric analyze and the surface area was measured by BET analysis. TEM observation showed that Fe and Ni nanoparticles was well dispersed on the carbon black and their average particle size was 4.82 nm. The loading weight of Fe-Ni nanocatalysts on the carbon black was 6.83-7.32 wt%, and the value increased with increasing iron (II) acetylacetonate content. As the Fe-Ni loading weight increased, the specific surface area decreased significantly by more than 50%, because Fe-Ni nanoparticles block the micropores of carbon black. I-V characteristics showed that water electrolysis performance increased with increasing Ni nanocatalyst content.

• Resources Recycling
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• v.2 no.4
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• pp.27-32
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• 1993

A process has been studied to recover gallium from steelmaking dust which had several hundreds ppm of gallium. Aqueous solution containing 38 mg/l gallium was obtained by leaching of dust with 2.25 mol/l sulfuric acid. The leach liquor contained iron and zinc about 1,000 times greater than gallium. Gallium was then concentrated by ion exchanger of chelating resin with functional group of amino carboxylic acid after reduction of ferric ion to ferrous ion and pH adjustment. Gallium was concentrated to be 13 g/l in the resulting eluate by double ion exchanges. The liquor was further treated to remove impurities by solvent extraction technique empolying TOMAC as extractant. The galluim with 99% purity was finally obtainable.

• Journal of the Korean Chemical Society
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• v.26 no.5
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• pp.320-325
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• 1982

Utilyzing the solution prepared for the sulfur determination, the amounts of iron, copper and cobalt in the sulfide ore were determined by X-ray fluorescence spectrometry. The samples were dissolved with the mixed solutions of ,$Br_2\;and\;HNO_3$ and a major constituent of $SiO_2$was repelled from the solution by HF treatment several times. The analytical results agreed with the data obtained by conventional methods within ${\pm}$1.5% for Fe of the range of 20 to 50%, ${\pm}$1.0% for Cu of 10 to 15%, and ${\pm}$0.4% for Co of 1 to 5%. The present method was tolerably found to be reproducible.

• Resources Recycling
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• v.2 no.2
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• pp.16-21
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• 1993

This study was carried out to investigate the settling characteristics of Fe(II) and Fe(III) hydroxide precipitates formed by pH adjustment of aqueous solution to remove ferrous and ferric ion in waste water. The results obstained in this study are as fellows : The settling rate was effectively increased with increasing the pH values of aqueous solution regulated by CaO and with increasing the amount of flocculant, on the other hand, application of excess flocculants decreased the settling rate. It is desirable that the concentration of iron ion is kept under $10^{-2}$ mol/ㅣ because the settling rate was decreased with increasing the concentration of iron hydroxide precipitates.

• Journal of Physiology & Pathology in Korean Medicine
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• v.23 no.1
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• pp.113-120
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• 2009

This study was performed to investigate the effects in inflammatory and pain status on rheumatoid arthritis(RA) induced rats by swimming exercise and Achyranthes Radix(AR) extracts ointment according to the application methods with the change of motor-behavioral and histochemistry study through the change of safranin o-fast green stain in the knee joint and prostaglandin $E_2(PGE_2)$ concentration production in serum for 28 days. They were randomly divided into four groups; Group I: RA induction, Group II: application of only swimming exercise after RA induction, Group III: application of only AR extracts ointment after RA induction, Group IV: application of both AR extracts ointment and swimming exercise after RA induction. The following results were obtained. Volume change of hind paw edema and arthritis indices test and arthritic dorsal flexion & plantar flexion pain test, group II, III, IV were showed that significantly decrease to each scores compared with group I (p<.01). Safranin o-fast green stain were showed histological indices, group II, III, IV were showed that significantly decrease the scores of cellular infiltration and synovial hyperplasia(p<.05), pannus formation and cartilage destruction(p<.01) compared with group I. Group IV were the most decreased compared with group II, III. The $PGE_2$ concentration of the group II, III, IV were decreased compared to the group I (p<.01) In conclusion, swimming exercise and AR extracts ointment acts were the most therapeutic intervention in inflammatory and pain control of RA induced rats.

• Journal of Physiology & Pathology in Korean Medicine
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• v.25 no.6
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• pp.1000-1007
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• 2011

This study was conducted to determine the analgesic effect of onion and acanthopanax senticosus mixture extract using the rheumatoid arthritis rat model. Rheumatoid arthritis model was made by the intradermal injection of type II collagen emulsified. Rats were divided into four groups: (1) Sham group(n=5), (2) Control group(administered DW 3 $m{\ell}$/1 day after RA induced, n=7), (3) Experimental group I(administered Onion extractor 600 mg/3 $m{\ell}$/1 day after RA induced, n=7). (4) Experimental group III(administered Onion and Acanthopanax senticosus mixture extractor 600 mg/3 $m{\ell}$/1 day after RA induced, n=7). After that, we examined the arthritic index, paw edema, pain threshold at 1st, 14th, 28th days. And also we examined histopathologic study(safranin-O green), immunohistochamical stain(COX-2) of knee joint at 28th days. Arthritic index, paw edema and pain threshold test were decrease in experimental group I, II than control group. Especially group II was most significantly inhibit effect than the other groups at 28th days. On the histopathologic view, all experimental groups were relieved and reproduced the erosion of arthritic site compared with control group. All experimental groups were COX-2 positive cells in the immunohistological stain of the knee joint were significantly decreased compared with control group. Especially group II was most significantly decreased than the other groups at 28th days. Onion and Acanthopanax senticosus mixture extractor can be used for curing rheumatoid arthritis. Anti-inflammatory effects may be somewhat better in combination of Onion and Acanthopanax senticosus.

• Journal of the Korean Society of Laryngology, Phoniatrics and Logopedics
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• v.23 no.2
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• pp.119-123
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• 2012

Background and Objectives : Sulcus vocalis could be classified into type I, type IIa, and type IIb. There have been a little reports about voice quality and treatment results related with types of sulcus vocalis. The authors conducted an analysis of voice and treatment according to different types of sulcus vocalis. Materials and Methods : This study was based on a retrospective chart review. The sulcus types were classified into type I and type II. Objective and subjective voice assessments were analyzed. Patients were treated individually with voice therapy, percutaneous steroid injection, and injection laryngoplasty. Comparison was performed on the voice difference between type I group and type II group, and between pre-treatment and post-treatment of each types. Results : One hundred and one patients were enrolled into this study, and 49 patients were type I and 52 patients were type II. Type I group showed longer mean maximal phonation time (MPT) than type II group, although other voice parameters didn't show any difference between two groups. Even after the management, almost all of the voice parameters didn't show improvement except MPT of type II group. Conclusion：Although the type I sulcus has been known as a non-pathologic lesion, it can result in some degree of voice change and discomfort, and thus need an active management. In this study, voice therapy, percutaneous steroid injection, and injection laryngoplasty showed limited effect to the both types of sulcus vocalis. Further studies for management of sulcus vocalis were needed.

• Analytical Science and Technology
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• v.9 no.3
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• pp.292-301
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• 1996

The synthesis of poly(ether)tailed bipyridine complex as redox reaction probes has advanced attempts to interpret very slow diffusion and heterogeneous electron transfer. Diffusion coefficients as low as $1.5{\times}10^{-15}cm^2/s$ have been observed for the oxidation of neat $Co(bpy(ppgm)_2)_{3^-}(ClO_4)_2$ with $LiClO_4$ electrolyte. Heterogeneous electron transfer rate constants of materials were found to vary with diffusion coefficient. The decrease in k as the diffusion coefficient decreases was actually caused by the decreasing D. Diffusion coefficient for compound of strong ion pairing anion($ClO{_4}^-$) was much smaller than the diffusion coefficient for compound of weak ion pairing anion($CF_3COO^-$).

• The Korean Journal of Pain
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• v.14 no.2
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• pp.214-217
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• 2001

Background: Intra-articular injection is a commonly performed procedure in patients with degenerative osteoarthritis of the knee. Several drugs are used for relief of pain in such cases. Local anesthetics, clonidine and steroids have been confirmed to be effective when used in an intra-articular injection. Ketorolac has recently become one of the most commonly used and potent NSAIDs. There have been many studies about the effect of ketorolac. Methods: Sixty-four patients were divided into 2 groups. In Group I (n = 31), 0.5% bupivacaine 3 ml and sodium hyaluronate 20 mg were used and in Group II (n = 33), 0.5% bupivacaine 3 ml, sodium hyaluronate 20 mg and ketorolac 5 mg were used. We observed the pain relief scale (PRS) at 15 minutes, 1 week and 1-3 months after injection. Results: After 15 minutes, PRS scores were $6.6{\pm}2.7$ (Group I) and $5.1{\pm}3.1$ (Group II), so there was a statistical difference between the two groups. After 1 week, the PRS scores were $5.9{\pm}2.0$ (Group I) and $5.8{\pm}2.4$ (Group II). At 1-3 months later, PRS scores were $5.6{\pm}3.0$ (Group I) and $5.1{\pm}2.7$ (Group II). Thus, there were no significant statistical differences between the two groups at 1 week or 1-3 months later, although some patients were more satisfied with pain relief in Group II at 1-3 months. Conclusions: Ketorolac provides more rapid pain relief of degenerative arthritis when used in intra-articular injection. And there was no statistical difference of effect after 1 week or 1-3 months later. Further studies are required on the effect of the intra-articular use of ketorolac.

• Journal of the Korean Chemical Society
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• v.33 no.6
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• pp.607-613
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• 1989

The chemical equilibria of Ni(II)-tetraamine (tetraamine = 2,12-dimethyl-3,7,11,17-tetraazabicyclo-11,3,1-heptadeca-1(17),2,11,13,15-pentaene) complex ion in water, acetonitrile, acetone and nitromethane were investigated using spectrophotometric method, respectively. The equilibria between low-spin ($D_{4h}$) and high-spin ($O_h$) structures of Ni-tetraamine complex ion were presented in water, acetonitrile and acetone, but not in nitromethane. The eqilibrium constants, the reaction enthalpies and the reaction entropies were determined from analysis of the temperature dependence of the electronic spectra. The formation of the triplet species ($O_h$) was found to be exothermic. The solvent and electrolyte effects on the equilibrium constants could be explained by the dielectric constants of solvents and the reaction entropies.