• Applied Biological Chemistry
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• v.41 no.6
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• pp.465-470
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• 1998

For the need of bio-degradable flocculant in stage of wastewater treatment, some cultural conditions of bioflocculant production were optimized with Aeromonas hydrophila KH-54. About 260 strains of type culture and bacteria isolated from marsh, pond, activated sludge, etc were examined for their ability to flocculate kaolin particles and swine wastewater. Among them, KH-54 showed the highest flocculating activity and was identified as Aeromonas hydrophila according to the cultural, morphological and physiological properties. The maximum production of the flocculant secreted by Aeromonas hydrophila KH-54 was observed in culture medium containing 2.0% mannitol, 0.05% ammonium chloride, 0.02% potassium phosphate dibasic, 0.01% $MgSO_4{\cdot}7H_2O$ and 0.05% yeast extract at initial pH 7.0 when cultured on rotary shaker controlled at $25^{\circ}C$ and 150 rpm. Under the optimized condition, the flocculating ability reached to 770 units/ml of kaolin flocculating activity and 81% of NTU removal efficiency against swine wastewater after 4 days cultivation. The bioflocculant was also effective on various organic wastewaters other than swine wastewater, showing NTU removal rate ranging from 92% to 34%.

• Analytical Science and Technology
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• v.23 no.1
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• pp.45-53
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• 2010

For the determination of chlorine in uranium compound, analytical methods by using a steam distillation and a pyrohydrolysis have been developed. The steam distillation apparatus was composed of steam generator, distilling flask and condenser etc. The samples were prepared with an aliquot of LiCl standard solution and a simulated spent nuclear fuel. A sample aliquot was mixed with a solution containing 0.2 M ferrous ammonium sulfate-0.5 M sulfamic acid 3 mL, phosphoric acid 6 mL and sulfuric acid 15 mL. The chloride was then distilled by steam at the temperature of $140^{\circ}C$ until a volume of $90{\pm}5\;mL$ is collected. The pyrohydrolysis equipment was composed of air introduction system, water supply, quartz reaction tube, combustion tube furnace, combustion boat and absorption vessel. The chloride was separated from powdered sample which is added with $U_3O_8$ accelerator, by pyrohydrolysis at the temperature of $950^{\circ}C$ for 1 hour in a quartz tube with a stream of air of 1 mL/min supplied from the water reservoir at $80^{\circ}C$. The chlorides collected in each absorption solution by two methods was diluted to 100 mL and measured with ion chromatography to determine the recovery yield. For the ion chromatographic determination of chlorine in molten salt retained in a metal ingot, the chlorine was separated by means of pyrohydrolysis after air and dry oxidation, and grinding for the sample.

• Applied Biological Chemistry
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• v.21 no.1
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• pp.35-39
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• 1978

1) Caramel and original soybean sauce was obtained from under grade wheat flour. 2) Mixture of under grade wheat flour and ammonium Chloride or HCl was parched. Parch substance were mixed with water, and then were filtrated. This filtrated liquid is liquid of dextrin. The residue of the filtrated substance was contained protein and others. Liquid of dextrin were treated with HCl until reaction of $I_2$ is colorless. Liquid of dextrin was caramelized. The original soybean sause was obtained by the hydrolysis of residue. 3) Parching 200g of under grade wheat flour with 7g of ammonium chloride under $140^{\circ}C$. for 90mins. and then add about 200ml of water to it. About 150ml. of dextrin soln's can be obtain after filtration. 4) Caramelizing 150ml. of dextrin soln's was treated with liq. ammonia at $120^{\circ}C$ for 270mins. under $pH\;5{\sim}6$. it was possible to obtain 95g of $24^{\circ}B\acute{e}$ caramel. 5) When 25g of residue was hydrolysised with 75ml. of 18% HCl for 8hrs. boiling. it was possible to obtain 55ml. of $25^{\circ}B\acute{e}$ original soybean sauce. It is contain 2.20% of nitrogen.

• The Korean Journal of Physiology and Pharmacology
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• v.16 no.2
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• pp.91-95
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• 2012

The role of the kidney in combating metabolic acidosis has been a subject of considerable interest for many years. The present study was aimed to determine whether there is an altered regulation of renal acid base transporters in acute and chronic acid loading. Male Sprague-Dawley rats were used. Metabolic acidosis was induced by administration of $NH_4Cl$ for 2 days (acute) and for 7days (chronic). The serum and urinary pH and bicarbonate were measured. The protein expression of renal acid base transporters [type 3 $Na^+/H^+$ exchanger (NHE3), type 1 $Na^+/{HCO_3}^-$ cotransporter (NBC1), Na-$K^+$ ATPase, $H^+$-ATPase, anion exchanger-1 (AE-1)] was measured by semiquantitative immunoblotting. Serum bicarbonate and pH were decreased in acute acid loading rats compared with controls. Accordingly, urinary pH decreased. The protein expression of NHE3, $H^+$-ATPase, AE-1 and NBC1 was not changed. In chronic acid loading rats, serum bicarbonate and pH were not changed, while urinary pH was decreased compared with controls. The protein expression of NHE3, $H^+$-ATPase was increased in the renal cortex of chronic acid loading rats. These results suggest that unaltered expression of acid transporters combined with acute acid loading may contribute to the development of acidosis. The subsequent increased expression of NHE3, $H^+$-ATPase in the kidney may play a role in promoting acid excretion in the later stage of acid loading, which counteract the development of metabolic acidosis.

• Journal of the Korean Society of Food Science and Nutrition
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• v.35 no.6
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• pp.708-712
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• 2006

The chemical properties of yellow and red onion were investigated and analyzed to provide basic data for functional food materialization and processing. The moisture and nitrogen free extract contents of yellow and red onion were 92.80%, 5.13% and 92.47%, 5.59%, respectively. Mineral components of yellow and red onion were rich in K (123.64 and 114.41 mg%), Na (34.09 and 33.57 mg%) and P (27.04 and 20.56 mg%). The major free sugar of yellow onion were glucose (744.2 mg%) and fructose (705.9 mg%). Whereas major free sugar of red onion were sucrose (692.8 mg%) and fructose (517.3 mg%). Glutamic acid, phenylalanine and aspartic acid in yellow and red onion were major amino acids. Abundant free amino acids in yellow onion were hydroxy-L-proline (27.34 mg%), L-serine (27.34 mg%) and L-arginine (26.25 mg%). Abundant free amino acids in red onion were L-glutamic acid (16.35 mg%), ammonium chloride (15.22 mg%) and L-serine (10.93 mg%). Ascorbic acid contents are higher in red onion (28.34 mg%) than in yellow onion (19.20 mg%). Quercetin and total polyphenol of yellow and red onion were 15.24 mg%, 5.70 mg% and 0.319 mg/g and 0.248 mg/g, respectively.

• Journal of Food Hygiene and Safety
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• v.27 no.1
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• pp.18-23
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• 2012

Highly pathogenic avian influenza virus (HPAIV) is already panzootic in poultry and caused a considerable economic loss in poultry industry. In addition, HPAIV continues to cross species barriers to infect humans and other mammals, often with fatal outcomes. In this study, the virucidal efficacy of Citra-$Kill^{(R)}$ composed to quaternary ammonium chloride and citric acid was investigated against avian influenza H9N2 virus (AIV). A virucidal efficacy was determined with the viability of AIV contacted with the disinfectant in the allantoic membrane of chicken embryos. Citra-$Kill^{(R)}$ and AIV was reacted on the distilled water (DW), hard water (HW) or organic matter suspension (OM) condition. On DW condition, AIV was inactivated with 2,000 fold dilutions of Citra-$Kill^{(R)}$. When the antiviral effect on HW condition was evaluated, the antiviral activity of the disinfectant showed on 1,500 fold dilutions against AIV. With the investigation of the antiviral effect of the disinfectant on OM condition, AIV was inactivated on 500 fold dilutions of Citra-$Kill^{(R)}$. As Citra-$Kill^{(R)}$ possesses virucidal efficacy against AIV, the disinfectant solution can be used to limit the spread of animal viral diseases.

• Microbiology and Biotechnology Letters
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• v.20 no.5
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• pp.574-582
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• 1992

Exo-xylanase encoded by the xylA gene of Bacillus stearothermoPhillus was produced from Escherichia coli ]M109 carrying a recombinant plasmid pMGL Synthesis of the enzyme was observed to be cell-associated, and about 94% of the enzyme synthesized was located in the cytoplasmic region. The maximum production was attained when the E. coli strain was grown at $37^{\circ}C$ for 8 hours on the medium containing 0.5% fructose, 1.0% tryptone, 1.0% sodium chloride, and 0.5% yeast extract. The exo-xylanase was purified to homogeneity using a combination of salting out with ammonium sulfate, DEAE-Sepharose CL-6B ion exchange chromatography, Sephadex G-IOO gel filtration, and Sephadex G-150 gel filtration. The' purified enzyme was most active at pH 6.0 and $45^{\circ}C$. $Ca^{2+}$ and $Co^{2+}$ activated the exo-xylanase activity by about 20% while $Ag^{2+}$, $Fe^{2+}$, $Mg^{2+}$ and $Zn^{2+}$ inhibited the enzyme activity by up to 60%. The $K_m$, value on p-nitrophenyl-$\beta$-D-xylanopyranoside was 2.75 mM. The enzyme had a pI value of 4.7. The estimated molecular weight of the native protein was 200,000 daL SDS-polyacrylamide gel electrophoresis analysis suggested that the native enzyme was a trimer composed of three identical 66,000 da!. polypeptides. The purified enzyme efficiently converted all the xylo-oligosaccharides tested to xylose. It was also confirmed that the enzyme split xylans in an exo-manner even though the degree of hydrolysis was fairly low. The xylanolytic enzyme was, therefore, classified to be one of the few bacterial exo-xylanases lacking transferase activity.

• Journal of the Korean Chemical Society
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• v.8 no.3
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• pp.113-120
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• 1964

The critical examination of the spectrophotometric method for determining microgram quantities of phosphate by the n-butyl acetate extraction as molybdophosphoric acid and subsequent development of the molybdenum blue has been made. In this procedure from 2 to 8 ${\mu}g$. of phosphate-phosphorus can be determined under optimum conditions. The final concentration of ammonium molybdate and the final acidity of perchloric acid for the formation of heteropoly acid are suitable to be ranges of 0.5 to 1.1% and 0. 5 to 1. 1 N respectively, and subsequently extracted with 10 ml. of n-butyl acetate. The extract is developed to molybdenum blue with 5.0 ml. of 1. 3% stannous chloride in 1N hydrochloric acid. The color is stable for at least one hour in the use of perchloric acid for the condensation. In order to determination of submicrogram amounts of phosphate, the sensitivity of the molybdenum blue method is hardly sufficient, a sensitive and stable molybdenum(V)-thiocyanate complex method has been investigated. By the procedure less than 1.2 ${\mu}g$. of phosphate-phosphorus can be determined with an accuracy of less than 5% the relative error. The molybdenum(Ⅵ) extracted by the above procedure is reduced to molybdenum(V) in the extract directly with a solution of 4 to 10% of stannous chloride, 0.5 to 1.5 mM of copper, and 0.1 to 0.9 N of perchloric acid as final concentration in 4.3 to 6.3 N of hydrochloric acid or 9.0 to 13.0 N of sulfuric acid by heating for one minute in boiling water, after cooling, the molybdenum(V)-thiocyanate complex color is developed by adding 6.0 M ammonium thiocyanate solution making the final concentration to be in a range of 0.4 to 0.9 M. This procedure the very sensitive, reliable, and stable can be applied to determining submicrogram amounts of phosphate in natural waters with a precision of 1.6 ${\times}\;10^{-2}$ the standard deviation as absorbance.

• Korean Chemical Engineering Research
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• v.46 no.4
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• pp.799-805
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• 2008

In general, anionic and cationic surfactants are incompatible because their mixtures form insoluble complexes and precipitate in the water. There are, however, some equimolar complexes of anionic and cationic surfactant that are soluble and behave like regular surfactants, specifically like nonionic surfactants, thus named pseudo-nonionic surfactant complexes. Pseudo-nonionic complexes are more effective and efficient in surface activities than their ionic surfactant components as shown by their equilibrium and dynamic surface tensions. They pack at the interface more than their ionic components. When a novel cationic surfactant, diglyceryl dodecyl dimethyl ammonium chloride(DGDAC), having the polyhydroxyl group at the hydrophilic head group, was mixed with a conventional anionic surfactant (sodium dodecyl sulfate; SDS) at equimolar ratio, we found that the aqueous equimolar mixture showed strong positive synergism in which molecular interaction parameter ${\beta}^M$ was very low, -17.2. According to the studies of equilibrium phase behavior and microscopy, this mixed system could form homogenous solutions containing vesicles.

• Polymer(Korea)
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• v.36 no.2
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• pp.169-176
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• 2012

Based on our experience in developing resistive humidity sensor, interdigital gold electrodes with different fingers and gaps have been fabricated on a glass epoxy (GE) substrate using screen printing techniques. The basic structure of the electrode consisted of a 3-, 4- and 5-fingers with gaps of 310 and 460 ${\mu}m$. Gold electrode/GE was prepared by first printing silver nanopaste, followed by consecutive electroless plating of Cu, Ni and then Au. Copolymer of [2-(methacryloyloxy)ethyl] dimethyl benzyl ammonium chloride (MDBAC) and methyl methacrylate (MMA) was used as a humidity-sensing polyelectrolyte, which was fabricated by a screen printing method on the Au electrode/GE substrate. The flexible humidity sensor showed acceptable linearity between logarithmic impedance and relative humidity in the range of 20-95%RH, low hysteresis of 1.5%RH, good response and recovery time of 75 sec at 1 V, 1 kHz, and $25^{\circ}C$. Electrode construction had a significant influence on the humidity-sensing characteristics of polymeric humidity sensors. The activation energy between electrode and ion conducting polyelectrolyte plays an important role in explaining the differences of humidity sensing characteristics such as temperature dependence, sensitivity, linearity and hysteresis.