• Fashion & Textile Research Journal
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• v.4 no.2
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• pp.192-197
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• 2002

On the whole the various medium colors were developed by repeat dyeing with different colorants after dyeing with one colorant in case of natural dyeing. In this study, however in order to obtain various colors on silk fabrics with natural dyes, pre-mordanting and combination dyeing were carried out. Metal compounds containing alum, copper and iron were used for pre-mordants. Gardenia and Sappan wood were used as colorants for combination dyeing. In combination dyeing of Gardenia and Sappan wood, these two natural colorants showed good miscibility in dye bath. The various colors were obtained according to various metal compounds for pre-mordants and various mixing portion of Gardenia and Sappan wood.

• Fashion & Textile Research Journal
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• v.5 no.1
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• pp.82-88
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• 2003

This study was carried out to investigate combination dyeing of the cationized cotton with natural colorants extracted from Gardenia and Sappan wood extract using methanol. To improve dyeing properties of cotton with natural dye, cotton fabric was preheated with cationizing agent containing chlorohydrine group in aqueous solution of sodium hydroxide. On the whole the various medium colors were developed by repeat dyeing with different colorants after dyeing with one colorant in case of natural dyeing, In this study, however in order to obtain various colors on cationized cotton fabrics with natural dyes, pre-mordanting and combination dyeing were carried out. The various colors were obtained according to various metal compounds for pre-mordants and various mixing portion of Gardenia and Sappan wood. Metal compounds containing alum, copper and iron were used for pre-mordants.

• Natural Product Sciences
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• v.5 no.1
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• pp.20-24
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• 1999

Bioassay-guided fractionation of anti-emetic constituents of Alpinia katsumadai Hayata was performed. Nine compounds including one novel compound, (3R,5S)-trans-3,5-dihydroxy-1,7-diphenyl-1-heptene (9) were isolated from it. Among these compounds, four diarylheptanoids, one sesquiterpenoid and one flavonoid showed anti-emetic activity on copper sulfate induced-emesis in young chicks.

• Bulletin of the Korean Chemical Society
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• v.32 no.2
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• pp.434-438
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• 2011

Polycrystalline $CuInSe_2$ (CIS) was synthesized through solvothermal reactions in toluene with selected alkyl amines as complexing agents. The alkyl amines were used as reducing agent of selenium and catalytic ligands, enhancing the formation of CIS compounds in the colloidal solution. Toluene does not contribute the syntheses directly but minimizes the amounts of amines required for single phase CIS. We systematically studied the reactivity of amine compounds for the solovothermal syntheses, determined critical concentration of amine and the shortest reaction time. Crystallinity, morphology, chemical composition, and band gap of the prepared $CuInSe_2$ were respectively measured by X-ray diffraction, scanning electron microscopy, inductively coupled plasma atomic emission spectroscopy and UV-vis spectroscopy.

• Bulletin of the Korean Chemical Society
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• v.31 no.11
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• pp.3159-3162
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• 2010

To realize highly selective recognition of oxalate in water, a new chemosensing ensemble that behaves highly selective colorimetric recognition of oxalate in water at pH 7.4 has been developed. The ensemble was constructed by a pyrrole containing mononuclear copper complex and chromeazurol S. The ensemble shows a highly selective recognition of oxalate through an obvious color change from blue to yellow upon the addition of oxalate, whereas, other dicarboxylates such as malonate, succinate, fumarate, maleate, glutarate, adipate, phthalate, isophthalate and terephthalate do not induce any noticeable color changes. The oxalate recognition process is not significantly affected by other coexisting dicarboxylate.

• Journal of Welding and Joining
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• v.20 no.5
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• pp.106-112
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• 2002

In the present study, the wettability and interfacial tension between (bare Cu, electroless Ni/cu, immersion Au/Ni/Cu) substrates and indium solder were investigated as a function of soldering temperature, types of flux. The wettability of In solder increased with soldering temperature and solid content of flux. The wettability of In solder was affected by the substrate metal finish used, i.e., nickel, gold and copper. On the bare Cu substrate, In solder wet better than any of the substrate metal finishes tested. Intermetallic compound formation between liquid solder and substrate reduced the interfacial energy and improved wettability. For the identification of intermetallic compounds, X-Ray Diffraction(LRD) were employed. Experimental results showed that the intermetallic compounds, such as Cu11In9 and In27Ni10 are observed f3r different substrates respectively. The wetting kinetics is investigated by measuring wetting time with the wetting balance technique. The activation energy of wetting calculated for the In solder/cu substrate and In solder/electroless Au/Ni/Cu substrate are 36.13 and 27.36 kJ/mol, respectively.

• Journal of Welding and Joining
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• v.12 no.1
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• pp.80-93
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• 1994

The microstructure and fractography of the friction welded joint of Al to Cu have been investigated in order to understand the formation of intermetallic compounds and their effects on the failure in tensile test of the joint. The variation of welding pressure did not affect significantly the tensile strength of joint. However, the tensile strength of joint decreaed as welding time increased. The thickness of reaction layers of welded joints was several micro-meters and mainly composed of intermetallic compounds of $CuAl_2$, $Cu_9Al_4$ and Al+$CuAl_2$. The thickness of $CuAl_2$, $Cu_9Al_4$ was increased with welding time. However, $CuAl_2$ was gradually changed to $Cu_9Al_4$ which caused the decrease of tensile strength . Even though the morphology of fractured surfaces depended upon the welding time, the failure occurred along $CuAl_2$ intermetallic compound itself or between $CuAl_2$ and $Cu_9Al_4$ in most cases.

• Bulletin of the Korean Chemical Society
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• v.22 no.5
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• pp.481-487
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• 2001

Surface films formed prior to bulk reduction of lithium have been studied at gold, platinum, and copper electrodes in rigorously dried propylene carbonate solutions using electrochemical quartz crystal microbalance (EQCM) and secondary ion mass spectrometry experiments. The results indicate that the passive film formation takes place at a potential as positive as about 2.0 V vs. Li/Li+ , and the passive film thus formed in this potential region is thicker than a monolayer. Quantitative analysis of the EQCM results indicates that electrogenerated lithium reacts with solvent molecules to produce a passive film consisting of lithium carbonate and other compounds of larger molecular weights. The presence of lithium carbonate is verified by SIMS, whereas the lithium compounds of low molecular weights, including lithium hydroxide and oxide, are not detected. Further lithium reduction takes place underneath the passive film at potentials lower than 1.2 V with a voltammetric current peak at about 0.6 V.

• Bulletin of the Korean Chemical Society
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• v.12 no.4
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• pp.445-449
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• 1991

A series of trisilaalkanes has been prepared in high yields by the direct reaction of ${\alpha}$ -chloromethylsilanes with metallic silicon in the presence of copper catalyst using the stirred reactor equipped with a spiral band agitator at the carefully controlled temperature between $280^{\circ}C$ and $340^{\circ}C.$ Disilaalkane compounds were obtained as the minor products. Cadmium was found to be a good promotor for the reactions, while zinc was an inhibitor.

• The Korean Journal of Pharmacology
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• v.17 no.2
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• pp.31-36
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• 1981

Heavy metals which are present as trace elements in human body have been known to modify various enzymatic reaction. These metals can be essential or non-essential. Zinc, copper and calcium are essential in maintaining some biological processes, whereas non-essential metals such as cadmium, lead and mercury produce accumulatve toxic effect. Cadmium accumulated in pancreas can cause toxicity and damage of pancreatic cells, thereby influencing CHO metabolism. Lead compounds are known to produce toxic effects on the kidney, digestive system and brain fellowed by inhibition of activity of ${\rho}-aminolevulinic$ acid and biosynthesis of hemoproteins and cytochrome. Evidence has been accumulated that zinc not only acts as a cofactor in enzyme reaction but also prevents toxic effect induced by heavy metal such as copper and cadmium. To demonstrate the effect of heavy metals on pancreatic secretion, part of uncinate pancreas was taken and incubated in Krebs-Ringer bicarbonate buffer with heavy metals used. Additional treatment with CCK-OP was performed when needed. After incubation during different period of time, medium was analyzed for amylase activity using Bernfeld's method. The present study was attempted in order to elucidate the effect of several kinds of heavy metal on exocrine pancreatic secretion in vitro. The results obtained are as follows: 1) CCK-OP stimulated significantly amylase release from pancreatic fragments in vitro. 2) CCK-OP response of amylase release from pancreatic fragments was inhibited by treatmant with cadmium, especially high doses of cadmium. 3) CCK-OP response of amylase release from pancreatic fragments was inhibited when pretreated with $10^{-4}M$ copper chloride. 4) Lead chloride at the concentration of $10^{-3}M\;and\;10^{4}M$ stimulated the basal amylase release in vitro but CCK-OP response did not augment by lead chloride. 5) Zine chloride did not affect amylase release from pancreatic fragment in vitro. From the results mentioned above, it is suggested that CCK-OP response was inhibited it the amylase release from pancreatic fragments pretreated with cadmium and copper chloride.