• Journal of the Korean Chemical Society
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• v.16 no.6
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• pp.361-368
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• 1972

The organic solvent mixture of 5 % trioctylamine and 5 % n-octyl alcohol in n-hexane could be loaded with tungsten to 62 g $WO_3$/1 whereas the amine alone could be loaded only to 37 g $WO_3$/1. Molecular interaction between amine and tungstate ion during the solvent extraction process and the synergistic effect of alcohol in enhancing the solubility of the amine-tungstate complex have been studied by NMR spectroscopy. Tungsten has been shown to be extracted as a polymeric tungstate ion into the organic phase to form a trioctyl ammonium polytungstate salt, which was more stabilized in the hydrocarbon medium by interacting with alcohol via hydrogen bonding between the tungstate ion and alcohol.

• Bulletin of the Korean Chemical Society
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• v.30 no.8
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• pp.1733-1737
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• 2009

A new cathode material based on Li$Ni_{0.8}Co_{0.15}Al_{0.05}O_2$ (LNCA)/polyaniline (Pani) composite was prepared by in situ self-stabilized dispersion polymerization in the presence of LNCA. The materials were characterized by fourier transform infrared spectroscopy (FT-IR), ultraviolet-visible spectroscopy (UV-Vis), X-ray diffraction (XRD), and scanning electron microscopy (SEM). Electrochemical properties including galvanostatic charge-discharge ability, cyclic voltammetry (CV), capacity, cycling performance, and AC impedance were measured. The synthesized LNCA/Pani had a similar particle size to LNCA and exhibited good electrochemical properties at a high C rate. Pani (the emeraldine salt form) interacts with metal-oxide particles to generate good connectivity. This material shows good reversibility for Li insertion in discharge cycles when used as the electrode of lithium ion batteries. Therefore, the Pani coating is beneficial for stabilizing the structure and reducing the resistance of the LNCA. In particular, the LNCA/Pani material has advantageous electrochemical properties.

• Clean Technology
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• v.20 no.4
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• pp.354-358
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• 2014

Ionic liquid (IL) is a salt presents in a liquid form at room temperature. Recently, it attracts huge attention due to its possibilities as a clean solvent, electrolyte, and catalyst. In the present work, the charging behavior of six different ILs were investigated using droplet contact charging phenomenon in a dielectric medium. Basically, the charging of an IL droplet can be explained by a perfect conductor theory. However, there were several different features depending on the species of ions of ILs, which requires rigorous molecular level modeling of charge transport through electrochemical reaction of IL. We hope the present results contribute to build up fundamental understanding of electrochemical charge transport of IL.

• Korean Journal of Rural Living Science
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• v.9 no.2
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• pp.33-41
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• 1998

This study is to find out the effects of the qualify of the breads made from Korean and imported wheat flour respectively after adding chitosan, by examining the dough making, the bread making properties, the Physicochemical properties of the breads. The low polymerized chitosan (M. W. : 37,000) was added respectively 1, 3 and 5% in the form of 10% lactic acid aqueous solution. The Korean wheat bread had 4% more water, 3% more sugar, 0.5% more salt, 3% more margarine and 1.5% more yeast per 100% to wheat flour added than the imported wheat bread. The bread volume for the two groups stayed the same. The water absorption in the chitosan added group was increased more greatly than in the control group, however, pH was reduced. In case of color among all wheat bread groups the ‘L’ value appeared to be higher in the imported wheat bread groups, and the ‘b’ value appeared to be higher in the chitosan added group.

• Membrane and Water Treatment
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• v.6 no.3
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• pp.173-187
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• 2015

The goal of present work is the preparation of a novel positively charged nanofiltration (NF) membrane and its development for the cation removal of aqueous solutions. This NF membrane was fabricated by the surface modification of polysulfone (PSf) ultrafiltration support. The active top-layer was formed by interfacial cross-linking polymerization of poly(ethyleneimine) (PEI) with p-xylylene dichloride (XDC) and then quaternized with methyl iodide to form a perpetually positively charged layer. In order to improve the efficiency of nanofiltration membrane, the concentration of PEI, XDC and methyl iodide solutions, PEI coating and cross-linking time have been optimized. As a result, a high water flux and high $CaCl_2$ rejection (1,000 ppm) was obtained for the composite membrane with values of $18.29L/m^2.h$ and 93.62% at 4 bar and $25^{\circ}C$, respectively. The rejections of NF membrane for different salt solutions followed the order of $Na_2SO_4$ < $MgSO_4$ < NaCl < $CaCl_2$. Molecular weight of cut off (MWCO) was calculated via retaining of PEG solutions with different molecular weights that finally, it revealed the Stokes and hydrodynamic radius of 1.457 and 2.507 nm on the membrane selective layer, respectively. The most efficient positively charged nanofiltration membrane exhibited a $Ni^{2+}$ rejection of 96.26% for industrial wastewater from Shamse Hadaf Co. (Kashan, Iran).

• Macromolecular Research
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• v.17 no.8
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• pp.597-602
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• 2009

Although the existing design principle of full-sequence ionic complement is convenient for the development of peptides, it greatly constrains the exploration of peptides with other possible assembly mechanisms and different yet essential functions. Herein, a novel designed half-sequence ionic complementary peptide (referred to as P9), AC-Pro-Ser-Phe-Asn-Phe-Lys-Phe-Glu-Pro-$NH_2$, is reported. When transferred from pure water to sodium chloride solution, P9 underwent a dramatic morphological transformation from globular aggregations to nanofibers. Moreover, the rheological experiment showed that the P9 could form a hydrogel with a storage modulus of about 30 Pa even at very low peptide concentration (0.5% (wt/vol)). The P9 hydrogel formed in salt solution could recover in a period of about 1,800 sec, which is faster than that in the pure water. The data suggestcd that the half-sequence, ionic complementary peptide might be worthy of further research for its special properties.

• Biomolecules & Therapeutics
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• v.4 no.2
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• pp.184-189
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• 1996

General pharmacological studies of LB20304a (a mesylate salt form of a new quinolone antibiotic LB20304 following oral administration of 300 mg/kg and 1000 mg/kg, almost maximum tolerance dose in mice and rat, respectively, were performed in terms of effects on general behaviour, central nervous system, gastrointestinal system, and blood coagulation system in mice and rats. With regards to general behaviour of mice, at oral dose of 300 mg/kg, LB20304a reduced muscle tone and locomotor activity. In terms of CNS, at oral treatment of 300 mg/kg, LB20304a showed some analgesic effects in mice, and oral dose of 1000 mg/kg caused drop in normal body temperature of rat, while it enhanced the pentylenetetrazole-induced clonic convulsion to tonic convulsion and/or death in mice at the doses of unto 300 mg/kg. In addition, LB20304a increased hexobarbital-induced sleeping time two and three times in mice at oral doses of 20 mg/kg and 300 mg/kg, respectively. Rota-rod and traction test in mice were not influenced by the dose of 300 mg/kg and 200 mg/kg, respectively. LB20304a reduced gastric secretion of rat at dose of 1000 mg/kg, and increased intestinal motility of mice at dose of 300 mg/kg. In rats, blood coagulation index, such as PT (prothrombin time) and aPTT (activated partial thromboplastin time) were not affected by the treatment of upto 1000 mg/kg of LB 20304a.

• Korean journal of food and cookery science
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• v.10 no.3
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• pp.260-266
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• 1994

The object of this study was investigation of the appreciable cooking condition in seven wild grasses, an evening primerose(Oenothera lamarckiana Seringe, S$_1$), a spiderwort(Commelina Communis L. S$_2$), the flower of a convolvulus(Calystegia Ja-ponica form Vulgaris gaea, S$_3$), So Ru Jaeng Yi(Portulaca Oleracea, S$_4$), Shoe Bi Rum(Portulacae Oleracea L, S$_5$), O Yi Pul(Sanguisorb aOfficinalis, S$_6$), Jip Sin Na Mul(Agrimonia poisa var. Japonica Nakai, S$_7$), in order to find out the importance as an useful vegetables. In this work 7 wild grasses with different soaking solutions and boiling conditions were examined to investigation the preference factors by sensory evaluation. Results of sensory evaluation for samples showed a significant difference at 1% and 5% level There were high significant differents in samples boiled for different time about astringent taste, bitter taste, perfume, green color and grassy smell at 1% and 5% level. In cooking methods of 7 samples, Namul was liked best and Guk, Salad and Fritter were followed. The condiments which were used for seasoning Namul were Gochujang. Soy Paste, Salt. Gochujang was most preferred.

• Journal of the Korean institute of surface engineering
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• v.32 no.1
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• pp.67-77
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• 1999

The Ni base superalloy Mar-M247 substrate was aluminized or aluminized after boronizing by the pack cementation under Ar atmosphere. The hot corrosion resistance and after-heat-treatment effect of aluminized specimens were studied by the cyclic hot corrosion test in $Na_2SO_4$-NaCl molten salt. XRD analysis showed that the $Ni_2Al_3$ phase was formed between the coated layer and substrate below 1273K but the NiAl phase above 1273K. The peak of the NiAl phase was developed after heat treatment. Corrosion test showed that corrosion resistance of the specimen with the NiAl phase was better than that with the $Ni_2Al_3$ phase. Corrosion resistance could be improved by heat treatment to form ductile NiAl phase, where cracks were not formed by thermal shock on coating layer. Moreover, it appeared that heat treatment played a role to improve corrosion resistance of Al diffusion coating above 1273K. The existence of boron in the Al diffusion coating layer obstructed outwared diffusion of Cr from the substrate, and it influenced on corrosion resistance of the coating layer by weakening adherence of the oxide scale.

• Bulletin of the Korean Chemical Society
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• v.15 no.9
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• pp.743-748
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• 1994

Photochemical reactions of saccharin with tertiary amines were explored. Saccharin was found to undergo an acid-base reaction with N-trimethylsilylmethyl-N,N-diethyl amine to form N-trimethylsilylmethyl-N,N-diethyl ammonium saccharin salt which is in equilibrium with free saccharin and N-trimethylsilylmethyl-N,N-diethyl amine insolution. Photoreaction of N-trimethylsilylmethyl-N,N-diethyl ammonium saccharin in $CH_3OH\;or\;CH_3CN$ results in the generation of desilylmethylated product, N,N-diethyl ammonium saccharin mainly along with benzamide. Photoreaction of N-methylsaccharin with N-trimethylsilylmethyl-N,N-diethyl amine in $CH_3OH$ leads to the production of o-(N-methylcarbamoyl)-N-ethylbenzenesulfonamid e as the major product along with N-methylbenzamide as the minor product. On the other hand, photoreaction of N,N,N-triethyl ammonium saccharin, generated from saccharin and triethylamine, produces N-methylbenzamide as the exclusive product. These photoreactions are quenched by oxygen indicating that triplets of saccharin and N-methylsaccharin are the reactive excited states. Based on the consideration of the redox potentials of saccharin and N-trimethylsilylmethyl-N,N-diethyl amine, and the nature of photoproducts, pathways involving initial triplet state single electron transfer are proposed for photoreactions of the saccharins with the ${\alpha}$-silylamine.