• Journal of Ginseng Research
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• v.13 no.2
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• pp.189-197
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• 1989

A new quaternary ammonium compound, hydrolyzed ginseng-saponin quaternary (HGSQ), from Korean ginseng saponin and 2,3-epoxypropyltrimethylammonium chloride has been developed as a conditioning agent in cosmetics. This structure has a hydrophobic group from the aglycone of ginseng saponin which is biologically active and considered to be the most important component of the Korean ginseng. Its properties : surface tension, critical micelle concentration (CMC), eye irritation, sorption onto hair, force reduction(%) and moisture retention effect were studied. Its cationic character allows the molecule to be more substantive than ginseng saponin. HGSQ had good physical properties and was safe. enough as a cosmetic raw material. Also half-head tests of HGSQ-containing shampoo were carried out to compare the conditioning effects in shampoos. HGSQ was an excellent conditioning agent in shampoo..

• Journal of the Korean Chemical Society
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• v.33 no.2
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• pp.257-262
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• 1989

An efficient asymmetric synthesis of (+)-1-aminoalkyphosphonic acids is achieved by alkylation of Schiff base, prepared from diethylaminomethylphosphonate and (S)-(-)-2-hydroxypinan-3-one as a chiral reagent, and a new method of column chromatographic resolution of (${\pm}$)-1-aminobenzylphosphonic acid via its Schiff base with (S)-(-)-2-hydroxypinan-3-one is described.

• Bulletin of the Korean Chemical Society
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• v.35 no.9
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• pp.2765-2768
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• 2014

Flower-like Au nanoparticles, so-called Au nanoflowers (AuNFs), were synthesized by simply adding ascorbic acid to a gold acid solution in the presence of a chitosan biopolymer. The chitosan-entangled AuNFs exhibited strong plasmon absorption in the near-infrared (NIR) wavelength due to the aggregation of primary Au nanoparticles. The chitosan-entangled AuNFs were preferentially adsorbed by Raman-active 2-chlorothiophenol (CTP) molecules, and the CTP-encoded AuNFs (AuNF-CTPs) were subsequently coated with a thin silica layer by a sol-gel reaction with Si alkoxides. The silica-coated AuNFs (AuNF-CTPs@silica) exhibited the distinct Raman signals of adsorbed CTP molecules, as a potential nanoprobe with surface-enhanced Raman scattering (SERS).

• Journal of Life Science
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• v.9 no.2
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• pp.212-215
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• 1999

Biologically active compounds in Polygonatum sibiricum were extracted using organic solvents as hexane, CHC1$_3$, n-butanol corresponding each component. Compound II was purified from hexane layer and the chemical structure of compound II was characterized using IH-nmr, 13C-nmr, DEPT135, COSY, HMQC, HMBC spectrum and MS-spectrum. Consequently, the chemical structure of compound II was determined as 2-Hydroxy-3-(9,12-(9E,12E)-Octadecadienoyloxy) propanoic acid.

• Macromolecular Research
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• v.11 no.6
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• pp.476-480
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• 2003

The rate of hydrolysis of Langmuir monolayer films of biodegradable polylactide (PLA) derivates was investigated at the air/water interface. The present study investigated such parameters as surface pressure, pH, and time. The hydrolysis of polyester monolayers depended strongly on the subphase pH, the concentration of active ions. Under the conditions studied here, polymer monolayers showed faster rates of hydrolysis when they were exposed to a basic subphase rather than they did when exposed to acidic or neutral subphases. By increasing the concentration of the degradation medium, the hydrolytic rate of dl-PLA monolayers was accelerated (accelerating effect). In addition, the basic hydrolysis of modified PLA with small amounts of hydrophilic (benzyloxycarbonyl) methyl morpholine-2,5-dione or glycolide was much faster than that of the PLA homopolymer.

• Proceedings of the PSK Conference
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• 2003.04a
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• pp.261.2-262
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• 2003

In the course of our researches for biologically active compound from Korean algae, purification of the methanolic extracts of two brown algae (Sagassum Sagamianum and Ishige Okamurae) collected off Jeju Island afforded an antioxidant polyphenolic compound (1). The molecular formular of 1 was established as C$\sub$24/H$\sub$16/ O$\sub$13/ on the basis of the FAB mass and $\^$13/C NMR spectrum. (omitted)

• Journal of Institute of Control, Robotics and Systems
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• v.8 no.5
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• pp.413-417
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• 2002

The Internet technology has been recognized not only as a tool far communication in the 21st century but also as an environment for enabling changes in the paradigm of teaching and learning. This paper describes a web-based system development for chemical engineering education. Simulation and visualization of dynamic systems in the environment of a standard web-browser is made possible by extending its capabilities. ActiveX control is used to simulate the system tool far online representation of Virtual Lab. System that is developed using visual basic. The courseware is classified into tutorial, exercises, and virtual experiments.

• Archives of Pharmacal Research
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• v.17 no.5
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• pp.304-308
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• 1994

Among the new series of phenylacetamides, one of capsaicin derivatives, KR-25018 was found to have a very potent analgesic activity. Thus, the phamacological properties of KR-25018 were compared with those of morphine, capsaicin, and nonsteroidal antiinflammatory drugs (NSAIDs). The analgesic activities were evaluated in several animal models, using different stimuli, such as phenylbenzoquinone(PBQ)-induced weithing test, tail-filck test in mice and adjuvant arthritic flexion test in rat. The relationship of phamacological properties of KR-25018 to that of centrally acting opioids was assessed by the blocking test using naloxone. The analgesic potency of the KR-25018 $(MPED_{50}=0.89{\;}p.o.{\;}in{\;}PBQ-induced{\;}weithing{\;}test, {\;}MPED_{50}$=0.61$ s.c. in tail-flick test in mice0, with different action mechanism from morphine and NSAIDs, was comparable to that of morphine.

• Tribology and Lubricants
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• v.15 no.1
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• pp.90-97
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• 1999

Chemical-Mechanical Polishing (CMP) refers to a material removal process done by rubbing a work piece against a polishing pad under load in the presence of chemically active, abrasive containing slurry. CU process is a combination of chemical dissolution and mechanical action. The mechanical action of CMP involves tribology. The liquid slurry is trapped between the wafer (work piece) and pad (tooling) forming a lubricating film. For the first step to understand material removal rate of the CMP process, the lubricational analyses were done with commercial 100mm diameter silicon wafers to get nominal clearance of the slurry film, roll and pitch angle at the steady state. For this purpose, we calculate slurry pressure, resultant forces and moments at the steady state in the range of typical industrial polishing conditions.

• 한국정보디스플레이학회:학술대회논문집
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• 2002.08a
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• pp.108-112
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• 2002

A new pixel driving method for organic light-emitting diode (OLED) flat-panel display (FPD) is proposed. The new charge-pump passive-matrix pixel driver consists only of a storage capacitance and a rectifying diode, and no thin-film transistor (TFT) is needed. The new driver not only supplies a constant current to the OLED throughout the whole period of panel scanning like an active-matrix driver, but also provides a highly linear gray-scale control through a pure digital manner.