• Resources Recycling
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• v.26 no.4
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• pp.26-33
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• 2017

The behavior on the solvent extraction of heavy rare earths (HRE) by using PC88A was confirmed to demonstrate the possibility of recovery on the HRE from industrial wastewater, which consist of low concentration rare earth. We verified the extraction behavior of the HRE through a change of equilibrium pH, extractant concentration and A/O ratio, and also confirmed the stripping behavior depending on the type of mineral acids. At equilibrium pH 1.0, extraction of rare earth (RE) was completed from 95% to 100%. In all extraction conditions, it tend to be extracted in order of high atomic number. When A/O ratio was 10/1, Yb and Tm were concentrated at the maximum and increased 6-fold and 3-fold compared to initial concentration, respectively. To confirm the stripping behavior of the RE, three mineral acids were applied to the organic phase and consequently rate of stripping was increased in order of $HNO_3$, $H_2SO_4$ and HCl.

• Journal of the Korea Organic Resources Recycling Association
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• v.31 no.3
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• pp.15-25
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• 2023

In this study, silicon sludge from semiconductor dicing process is recycled to fabricate silica nanoparticles, which are applied as dispersing materials for electro-responsive (ER) smart fluid. In specific, metal impurities are removed from silicon sludge by acid washing to obtain the high-purity silicon powder. And then, silica nanoparticles are synthesized by facile hydrothermal method employing the silicon powder as reactant material. To control the size of silica nanoparticles, the reaction time of hydrothermal method is varied as 8, 15, 20, and 30 hours are applied to control the size of silica nanoparticles. Sizes of silica nanoparticles are increased proportionally to the reaction time owing to the increased numbers of hydrolysis and condensation reactions. As-synthesized silica nanoparticles are prepared as electro-responsive smart fluids by dispersing into silicon oil. Silica nanoparticles synthesized by 30 hours of hydrothermal reaction (SiO₂-H30) exhibit the highest shear stress of 21.4 Pa under an applied electric field strength of 3.0kV mm^-1. Such enhancement in ER performance of SiO₂-H30 among various silica nanoparticles are attribute to the reinforcing effect originated from the mixed particle size, which allowing the formation of rigid chain-like structures. Accordingly, this study successfully propose a recycling method of silicon sludge to synthesize silica nanoparticles and their derived ER fluids, which may suggest new possibility to ESG management emphasizing the eco-friendliness.

• Koreanishche Zeitschrift fur Deutsche Sprachwissenschaft
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• v.2
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• pp.307-342
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• 2000

Die Arbeit zeigt an, dass die kulturspezifische Textsortenkonvention der Gebrauchstextsorte 'Todesanzeige' im Mittelpunkt steht, wobei anhand von Sprachgemeinschaften vorgegangen wird. Das setzt bestimmte $Verst\"{a}ndnisse$ von Text und Textlinguistik einerseits und von Textsorte und Textsortenlinguistik andererseits voraus. Zuerst versuche ich einen Standort der Todesanzeige im Rahmen der Gebrauchstextsorte zu bestimmen. Danach erstelle ich eine Typologie der Todesanzeige. Die Wahl der klassischen Todesanzeige erlaubt die Kon-stituierung eines zweisprachigen Korpus, das als Grundlage $f\"{u}r$ die in Kapiteln $4\~6$ angestellte Paralleltextanalyse dient. Im Mittelpunkt steht dabei die Makrostruktur und die Textfunktion, also die kommunikative Funktion im Text der $ausgew\"{a}hlten$ Anzeigen, deren Einzelteile auf Struktur und Funktion untersucht werden. Die Gesamtstruktur der Todesanzeigen ist von der Zeitung und dem damit zusammenhangenden Kulturraum $abh\"{a}ngig.\;Au{\ss}er$ dem obligato-rischen Mitteilungs- und Abschlussteil finden sich in beiden $Kulturra\"{u}men$ nicht alle makrostrukturellen Elemente. Kulturbedingte Unterschiede zwischen den koreanischen und deutschen Anzeigen gibt es auch in der $Vorkommensh\"{a}ufigkeit$ einzelner Elemente und in ihren inhaltlichen und syntaktischen Merkmalen sowie in der Handlungsstruktur des Textes. Unterschiede gibt es auch in der H\"{a}ufigkeit$, im Umfang und lnhalt der verschiedenen Elemente sowie in ihrer sprachlichen Formulierung.

• Journal of Korean Society for Atmospheric Environment
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• v.19 no.1
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• pp.57-66
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• 2003

TiO$_2$ sol was prepared by sol-gel method, and this sol was coated in ceramic and glass bead by dip-coating method. The coated catalyst was applied to degrade benzene in the gas phase by exposing to UV -lamp (365 nm) in a batch reactor. The removal efficiency of the benzene was compared by changing various conditions such as the kind of chemical additives, the coating beads (ceramic and glass), solution pH, the initial concentration of TiO$_2$ sol, UV intensity, and benzene concentration. The physical structure of TiO$_2$ sol used in this study was found to be pu-rely anatase type from XRD analysis. The results showed that ceramic bead was effective as the coating agent rath-er than glass bead. The significant change in the benzene removal efficiency of benzene did not occur with chang-ing coating frequency and the initial concentration of TiO$_2$ sol. The removal efficiency of benzene increased with increasing UV intensity, and with acidic treatment of TiO$_2$-coated ceramic bead.

• Structural Engineering and Mechanics
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• v.50 no.2
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• pp.151-161
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• 2014

In this paper, fuel tank of the locomotive ER 24 has been studied. Firstly the behavior of fuel and air during the braking time has been investigated by using a two-phase model. Then, the distribution of pressure on the surface of baffles caused by sloshing has been extracted. Also, the fuel tank has been modeled and analyzed using Finite Element Method (FEM) considering loading conditions suggested by the DIN EN 12663 standard and real boundary conditions. In each loading condition, high stressed areas have been identified. By comparing the distribution of pressure caused by sloshing phenomena and suggested loading conditions, optimization of the tank has been taken into consideration. Moreover, internal baffles have been investigated and by modifying their geometric properties, search of the design space has been done to reach the optimal tank. Then, in order to reduce the mass and manufacturing cost of the fuel tank, Non-dominated Sorting Genetic Algorithm (NSGA-II) and Artificial Neural Networks (ANNs) have been employed. It is shown that compared to the primary design, the optimized fuel tank not only provides the safety conditions, but also reduces mass and manufacturing cost by %39 and %73, respectively.

• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.22 no.1
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• pp.29-33
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• 1986

This paper aims at finding out the optimum operating condition to reduce fuel consumption for the training ship Pusan 402 with controllable pitch propeller. For this purpose, this paper examints the variation of ship speed and fuel consumption in accordance with the change of engine revolution and propeller pitch. The results obtained are as follows: 1. When engine revolution is constant, the ship speed sluggishly increases according to the increase of propeller pitch but fuel consumption extremely increases. The higher revolution the engine is, the more remarkable this tendency is. 2. As the engine revolution becomes lower, the fuel consumption per mile decreases. Howt.er = the fuel consumption under the same engine revolution differs according to the propeller pitch. 3. Specific fuel consumption is uniformed about 180g/ps.h at any case of load. 4. Among the various operating conditions which yield the same ship speed, fuel consumption lowers in the case of lower engine revolution and larger propeller pitch.

• Journal of the Economic Geographical Society of Korea
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• v.17 no.3
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• pp.585-599
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• 2014

Zusammenfassung : Seit den 1990er Jahren hat Muenchen sich zu einem der fuehrenden europaeischen Biotechnologie Clustern entwickelt. Cluster, d.h. raeumliche Konzentrationen von miteinander vernetzten Unternehmen und Institutionen entlang einer Wertschoepfungskette, stellt fuer Unternehmen und Regionen einen erheblichen Wettbewerbsvorteil dar. Ziel dieser Beitrag ist es, die Herausbildung und Entwicklung des Innovationsclusters in Deutschland, am Beispiel von Biotech Cluster Muenchen zu analysieren. Im Folgenden wird zunaechst der Versuch unternommen, eine uebergreifende Kozeption regionaler Unternehmensclustern theoretisch zu eroerten. Darauf aufbauend wird anhand des Biotech Clusters Muenchen die Struktur und Entwicklung des Innovationsclusters empirisch aufgezeigt.

• Journal of Korean Society of Water and Wastewater
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• v.20 no.6
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• pp.893-904
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• 2006

To improve sensitivity of biosensor as yeast two-hybrid detection system for estrogenic activity of suspected chemicals, we tested effects of several combinations of the bait and fish components in the two-hybrid system on Saccharomyces cerevisiae inducted a chromosome-integrated lacZ reporter gene that was under the control of CYC1 promoter and the upstream Gal4p-binding element $UAS_{GAL}$. The bait components that were fused with the Gal4p DNA binding domain are full-length human estrogen receptor ${\alpha}$ and its ligand-binding domain. The fish components that were fused with the Gal4p transcriptional activation domain were nuclear receptor-binding domains of co-activators SRC1 and TIF2. We found that the combination of the full-length human estrogen receptor ${\alpha}$ with the nuclear receptor-binding domain of co-activator SRC1 was most effective for the estrogen-dependent induction of reporter activity among the two-hybrid systems so far reported. The relative strength of transcriptional activation by representative natural and xenobiotic chemicals was well correlated with their estrogenic potency that had been reported with other assay systems.

• Biodesign
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• v.5 no.4
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• pp.136-140
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• 2017

Lam6 is a member of sterol-specific ${\underline{l}ipid$ transfer proteins ${\underline{a}}nchored$ at ${\underline{m}ebrane$ contact sites (LAMs). Lam6 localizes to the ER-mitochondria contact sites by its PH-like domain and the C-terminal transmembrane helix. Here, we purified and crystallized the Lam6 PH-like domain from Saccharomyces cerevisiae. To aid crystallization of the Lam6 PH-like domain, T4 lysozyme was fused to the N-terminus of the Lam6 PH-like domain with a short dipeptide linker, GlySer. The fusion protein was crystallized under the condition of 0.1 M HEPES-HCl pH 7.0, 10% (w/v) PEG 8000, and 0.1 M $Na_3$ Citrate at 293K. X-ray diffraction data of the crystals were collected to $2.4{\AA}$ resolution using synchrotron radiation. The crystals belong to the orthorhombic space group $P2_12_12_1$ with unit cell parameters $a=59.5{\AA}$, $b=60.1{\AA}$, and $c=105.6{\AA}$. The asymmetric unit contains one T4L-Lam6 molecule with a solvent content of 58.7%. The initial attempt to solve the structure by molecular replacement using the T4 lysozyme structure was successful.

• Biomedical Science Letters
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• v.25 no.1
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• pp.23-31
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• 2019

The protein kinase $CK2{\alpha}$ (formerly Casein Kinase II) is implicated in tumorigenesis and transformation. However, the mechanisms of $CK2{\alpha}$ activation in breast cancer have yet to be elucidated. This study investigated the mechanisms of $CK2{\alpha}$ activation in estrogen signaling. Estrogen increased reactive oxygen species (ROS) production, $CK2{\alpha}$ activity, and protein expression in estrogen receptor positive ($ER^+$) MCF-7 human breast cancer cells, which were inhibited by the antioxidant N-acetyl-L-cysteine. $H_2O_2$ enhanced $CK2{\alpha}$ activity and protein expression. Human epidermal growth factor (EGF) increased ROS production, $CK2{\alpha}$ activity and protein expression in EGF receptor 2 (HER2)-overexpressing MCF-7 (MCF-7 HER2) cells, but not in MCF-7 cells. Estrogen induced the phosphorylation of p38 mitogen-activated protein kinase (MAPK). The p38 inhibitor, SB202190, blocked estrogen-induced increases in ROS production, $CK2{\alpha}$ activity and $CK2{\alpha}$ protein expression. The data suggest that ROS/p38 MAPK is the key inducer of $CK2{\alpha}$ activation in response to estrogen or EGF.