• Applied Chemistry for Engineering
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• v.8 no.4
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• pp.582-588
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• 1997

Synthetic reaction of TAME, ETBE, and MTBE compounds used largely for gasoline octane number enhancer to prevent air pollution was investigated using heteropolyacid catalyst in a fixed bed flow reactor. In the synthetic reaction of TAME, ETBE and MTBE, after hetero atom being replaced with poly atom, the activity of the catalyst, $H_4SiW_{12}O_{40}$ with coordinated bond with W and an hetero atom of Si was the highest among the catalysts tested. Also the activity depended upon the metals replaced which are related to the catalyst acidity. $FeHPW_{12}O_{40}$ and $K_3PM_{o12}O_{40}$ catalysts showed high activity in TAME synthesis, while they were not effective in ETBE and MTBE synthesis. In this study catalysts showing high activity were selected and mixed with equal weight combination of $H_4SiW_{12}O_{40}$ and $Sr_2SiW_{12}O_{40}$ ;$H_4SiW_{12}O_{40}$ and $NaH_2PW_{12}O_{40}$ ; $Fe_{1.5}PW_{12}O_{40}$ and $Mg_2SiW_{12}O_{40}$ ; $Mg_2SiW_{12}O_{40}$ and $Ba_2SiW_{12}O_{40}$. The mixed heteropolyacid catalysts showed higher TBA conversion rate and better selectivity of ETBE and MTBE than the single catalysts.

• Journal of Microbiology and Biotechnology
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• v.14 no.4
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• pp.673-679
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• 2004

A microbial cryoprotectant formulation using a W/O/W multiple emulsion system was developed. The psychrotolerant microorganism, B4, isolated from soil in South Korea, was observed by the drop freezing method, in which the microorganism sample inhibited ice nucleation activity. The antifreeze activity was eliminated when the microorganism sample was treated with protease, indicating that the antifreeze activity was due to the presence of antifreeze protein. The result of the l6S rDNA sequencing indicated the B4 strain was most closely related to a species of the genus Bacillus. Culture broth of B4 strain (Bacillus sp.) and rapeseed oil containing 1 % polyglycerine polyricinolate (PGPR) were used as core and wall material, respectively. The most stable W/O emulsion was prepared at a core/oil ratio of 1:2. The highest W/O/W emulsion stability was achieved when the primary emulsion to external aqueous phase containing 0.5% caster oil polyoxyethylene ether $(COG25^{TM})$ ratio was 1:1. Microcrystalline cellulose showed better W/O/W emulsion stability than other polymer types. The viability of cells in a W/O/W emulsion was higher than free cells during storage at $37^\circ{C}$. An acidic pH and UV exposure decreased the viability of free cells, but cells in W/O/W emulsion were more stable under these conditions.

• Applied Chemistry for Engineering
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• v.4 no.2
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• pp.308-317
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• 1993

The study is related to the synthesis of acrylic acid by selective oxidation of acrolein on Mo-V-W multicomponent mixed oxide catalysts. Mo-V-W-O(WVM), Mo-V-O/Mo-W-O(VM/WM), Mo-W-O/Mo-V-O(WM/VM) and mechanical mixtures of Mo-V-O and Mo-W-O(M-VM+WM) were prepared and characterized by BET, XRD, SEM and EPMA. Catalytic activity of these catalysts was tested in a continuous fixed bed reactor. In WVM catalysts small amount of tungsten added to VM increased surface area and selectivity of acrylic acid, but excess amount of tungsten decreased reaction rate of acrolein and selectivity. VM/WM catalysts, VM supported on WM, showed higher activity and selectivity than WM/VM catalysts where WM is supported on VM. Phase cooperation between WM and VM was observed in mechanical mixture of WM and VM and they showed higher yield than WM or VM.

• Koreanishche Zeitschrift fur Deutsche Sprachwissenschaft
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• v.4
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• pp.395-411
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• 2001

Die $W\"{o}rterb\"{u}cher$ spielen beim Erwerb einer Sprache eine wesentliche Rolle. Es gibt inzwischen mehrere Deutsch-Koreanische $W\"{o}rterb\"{u}cher$. Die Lage $f\"{u}r$ die Koreanisch-Deutschen $W\"{o}rterb\"{u}cher$ ist aber verbesserungs- $bed\"{u}rftig$. Stellvertretend $f\"{u}r$ das Koreanisch/Deutsche $W\"{o}rterbuch$ steht das 1981 von der Koreanischen Gesellschaft $f\"{u}r$ Germanistik nach $zehnj\"{a}hriger$ Arbeit fertiggestellte Essence Koreanisch-Deutsche $W\"{o}rterb\"{u}ch$ (Minjung seorim 1982). Dieses $W\"{o}rterb\"{u}ch$ weist aber einige Nachteilen auf. Es fehlen jegliche Angaben zum Korpus. Man $st\"{o}{\ss}t$ beispielsweise oft auf selten gebrauchte $W\"{o}rter$, die Grundbedeutungen sind nicht erkennbar, die Erklarungen sind ungenau, manchmal sogar $irref\"{u}hrend\;und\;schlie{\ss}lich$ mitunter stilistisch falsch. Diese negativen Punkte wirken sich $ung\"{u}nstig$ auf den gesamten Lemprozess bis hin zur Lemmotivation aus. Aus diesen Gegebenheiten $erw\"{a}chst$ die Notwendigkeit der Erstellung eines neuen $W\"{o}rterb\"{u}ch$s, das auf die Situation von Sprachlemem abgestimmt ist, die zur Benutzung einsprachiger $W\"{o}rterbticher$ noch nicht imstande sind. Zweck des $W\"{o}rterb\"{u}chs$ ist der Einsatz im Fremdsprachenunterricht, woraus sich ein zweisprachiges $W\"{o}rterb\"{u}ch$ ergibt. Als Benutzerkreis werden insbesondere $Sprachlemanf\"{a}nger$ des Koreanischen und Deutschen ins Auge gefasst. Ihnen soll ein Nachschlagewerk an die Hand gegeben werden, das den koreanischen und deutschen Wortschatz anhand einer Systematik und eines alphabetischen Indexes der jeweiligen Sprache $erschlie{\ss}t$. Ais Zahl der Lemmata wird $f\"{u}r$ jede Sprache ca. 10,000 festgelegt. Ein Grundwortschatz, der die 3000 $h\"{a}ufigsten\;W\"{o}rter$ umfasst wird extra markiert. $Dar\"{u}ber$ hinaus bietet das $W\"{o}rterb\"{u}ch$ den darauf aufbauende Wortschatz von weiteren 7000 $W\"{o}rtern$. Die Teamarbeit der beiden Gruppen von Muttersprachlern steht in allen Arbeitsschritten im Vordergrund. Der damit verbundene Zweck ist die Erzielung der maximalen Genauigkeit der $Lemmaerkl\"{a}rungen$. Da dieses $W\"{o}rterb\"{u}ch$ ein $W\"{o}rterb\"{u}ch$ nach Sachgruppen ist, die Erstellung einer Systematik von $gro{\ss}er$ Bedeutung. $F\"{u}r$ das vorliegende Projekt gait daher eine Systematik zu finden, die nicht nur leicht nachvollziehbar, also praktikabel ist, sondern insbesondere von Benutzern aus zwei Kulturkreisen akzeptiert werden kann. Als $grunds\"{a}tzliche$, allerdings nicht in allen Bereichen $gleicherma{\ss}en$ anwendbare Ordnungsprinzipien gelten: Vom Oberbegriff zum Unterbegriff, vom allgemein zum speziell, vom Einfach zum Komplexen, von $au{\ss}en$ nach innen, Darin spiegelt sich das Prinzip der 'notwendigen Bedingung' wider.

• Journal of Pharmaceutical Investigation
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• v.25 no.1
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• pp.55-62
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• 1995

W/O and O/W emulsions of tegafur (50 mg/5 ml/kg) were orally administered to rats to compare with their mesenteric lymphatic delivery effects. And also in order to demonstrate the lymph targeting associated to the oral route, it was deemed necessary to investigate the fate of solution after oral administration as a control. Lymph and plasma samples were periodically taken from each subject of mesenteric lymphatic duct cannulated rats. Then, lymph and plasma levels of tegafur and its active metabolite, 5-FU, were simultaneously observed. Also pharmacokinetic parameters were compared with each others. On the other hand, most previous studies of lymphatic transport have not addressed the question of whether an increase in mesenteric or thoracic lymph transport by the manipulation of a suspected variable was due to a selective delivery to the intestinal lymphatics or an overall increase availability. Therefore, based on a physiologically based pharmacokinetic model which represents the characteristics of lymphatic systems, we are also going to determine the contributions of mesenteric lymph transport versus thoracic lymph transport of tegafur reported in reference(13). In comparison with tegafur solution, AUC and mean residence time of plasma tegafur were significantly increased in W/O emulsion but significantly decreased in O/W emulsion. Lymph flow rates were similar in both solution and W/O emulsion but half in O/W emulsion. AUC of tegafur in mesenteric lymph and in plasma for W/O emulsion were 3.7 times and 2.9 times more than those for O/W emulsion, respectively. And AUC of 5-FU in thoracic lymph for W/O emulsion was 3.7 times more than that for O/W emulsion. These results suggested that lymphatic delivery or tegafur by W/O emulsion was more effective than that by on emulsion due to its differences or formation ability of chylomicrons.

• Polymer(Korea)
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• v.38 no.1
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• pp.103-107
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• 2014

Poly(acrylonitrile-butadiene-styrene) (ABS) composite sheets containing titanium dioxide ($TiO_2$), barium sulfate ($BaSO_4$), calcium carbonate ($CaCO_3$) were prepared by using a co-rotating twin screw extruder, and the reflectance and flexural modulus of the composite sheets were measured. The fillers were well dispersed in ABS matrix. The reflectance of composite sheet was increased with increasing $TiO_2$ and $BaSO_4$ content. Sheet having $TiO_2$ 20 wt% composition, with 5~20 wt% $BaSO_4$ resulted in more than 95% of reflectance. The flexural modulus of composite sheet was increased from 1864 MPa for $ABS/TiO_2/BaSO_4$ 85/10/5 (w/w/w) to 3134 MPa for $ABS/TiO_2/BaSO_4$ 55/20/25 (w/w/w).

• Journal of the Society of Cosmetic Scientists of Korea
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• v.19 no.1
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• pp.108-126
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• 1993

The functions of polyoxyethylene tocopheryl ethers [POE(n)TEs] in emulsion, solubilization and gel were studied. For emulsification of liquid paraffin, POE(10)TE showed better emulsifying effect in O/W emulsions than others tested. The effects of oil and polyol content on the formulation of W/O and O/W emulsions were also studied. In O/W emulsion, the viscosity was increased by increasing the liquid paraffin content, at about 70%, and slightly increased by increasing the propylene glycol content, However, in W/O emulsion, the viscosity was decreased by increasing the oil content, and also decreased by increasing the propylene glycol content, For solubilization of perfume oil, POE(18)TE showed better solubilizing effect than the others tested. The gelling effect of POE(n)TEs increased with ethylene oxide chain length up to 50 moles. The gelling property was evaluated for hardness and viscosity.

• Koreanishche Zeitschrift fur Deutsche Sprachwissenschaft
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• v.6
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• pp.345-365
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• 2002

In diesem Aufsatz wired versucht, eine Mikrostruktur $f\"{u}r$ ein elektronisehes Detusch-Koreanisehes $W\"{o}rterbueh$ zu entwerfen. Bei gedruekten $W\"{o}rterb\"{u}ehern$ sind die lexikographischen Daten und die $W\"{o}rterbuch­strukturen$ mehr oder weniger standardisiert, dagegen bei elektronischen $W\"{o}rterb\"{u}ehern$ strikt formalisiert. Im Laufe der letzten 50 Jahre sind zwar viele gedruekte, jedoch kaum auf Elektronik basierte zweisprachige $W\"{o}rterb\"{u}cher\;f\"{u}r$ Deutseh-Koreanisch ersehienen. Elektronische $W\"{o}rterb\"{u}cher$ haben mehre Vorteile und sind in diesem Informationszeitalter als Hilfsmittel $f\"{u}r$ den Fremdspraeherwerb unabdingbar. Die Festlegung der logischen Struktur des $W\"{o}rterbuehs\;ist\;f\"{u}r\;die\;W\"{o}rterbucharbeit\;unerl\"{a}{\ss}lich$ und $f\"{u}r$ die Herstellung elektronischer $W\"{o}rterb\"{u}cher$ von Bedeutung, wird jedoch in der koreanischen Praxis oft $vemachl\"{a}{\ss}igt$. Daher weisen die meisten koranischen $W\"{o}rterb\"{u}cher$ keine konsistente Form in der Struktur von $W\"{o}rterbuehdefinitionen$ auf. Aus diesen $Gr\"{u}nden$ schlage ich eine formale logisehe Struktur $f\"{u}r$ ein elektronisches Deutsch-Koreanisches $W\"{o}rterbuch$ vor. $Zun\"{a}chst$ werden grundlegende lexikalische Begriffe $eingef\"{u}hrt,\;anschlie{\ss}end$ wird auf die Analyse der lexikalischen $Eintr\"{a}ge\;f\"{u}r$ ein Deutsch-Koreanisches $W\"{o}rterbuch$ eingegangen. In diesem Beitrag wird keine fertige Miktostruktur $pr\"{a}sentiert$, sondern eine Anregung zur weiteren Diskussion zu einer Mikrostruktur gegeben. Als logisehe Struktur $f\"{u}r$ das elektronische Deutsch-Koreanische $W\"{o}rterbuch$ wird eine glattalphabetische Makrostruktur aufgenommen, die Mikrostruktur als semiintegriert. Die lexikographische Arbeit ist $zeitaufw\"{a}ndig$ und braucht viele $Fachkr\"{a}fte$. Deshalb ist die Festlegung einer konsistenten und objektiven Mikrostruktur eine Voraussetzung der $W\"{o}rterbuchherstellung$. Sie regt auch dazu an, die lexikalischen Informationen im Artikel genauer zu analysieren. Erst dadurch wird ein effektives elektronisches $W\"{o}rterbuch\;m\"{o}glich$, das eine Weiterbenutzung der klassifizierten Informationen $unterst\"{u}tzt$.

• Journal of the Society of Cosmetic Scientists of Korea
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• v.22 no.1
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• pp.40-59
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• 1996

Retinyl Palmitate, the skin normalzer, is useful to promote greater skin elasticity, to diminish lipid peroxidation and skin roughness following UV exposure, and promote a youthfull general skin appearance. We knew that the reduction of retinyl palmitate in W/O, W/S, O/W, MLV cream was caused by variable compound factors. Among the retinoids, we chose retinyl palmitate and studied the stability behavior of retinyl palmitate is liposomed. Furthermore, HPLC, CHROMA METERS, LASER SIGHT SCATTERING SYSTEM and FREEZE FRACTURE SCANNING ELECTROM MICROSCOPY was used to analyzing the stability and efficacy of UV and heat.

• YAKHAK HOEJI
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• v.39 no.5
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• pp.495-505
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• 1995

The O/W microemulsion systems were made from 2 or 4% (w/w) oil (soybean oil, olive oil or isopropyl myristate) and 10, 15 or 20% (w/w) Brij 96. They were compared with micellar solution of equivalent surfactant concentration m therms of physicochemical properties, and the solubilization of sudan IV. They were characterized by dynamic light scattering, stability, surface tension, viscosity and rheogram. The mean diameters of O/W microemulsion systems were 10-15nm, and those of Brij 96 micellar solutions were 18-19 nm. Both of them were monodisperse systems. The O/W microemulsion systems showed Newtonian flow and their apparent viscosities were lower than those of micellar solutions. The surface tensions of O/W microemulsion systems were increased or decreased depending on the types of oil used, when compared with those of micellar solutions. The O/W microemulsion systems were very stable, and did not show any flocculation or aggregation. Their mean diameters were not changed after three months. But oxidation was observed in microemulsions without nitrogen gas at high temperature. There was a significant improvement in the sudan IV solubffimtion in micromulsion compared with that m the micellar solution containing equivalent concentration of surfactant. The size distribution and mean diameters of O/W micromulsions were not changed when sudan IV was solubilized.