• Archives of Pharmacal Research
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• v.26 no.11
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• pp.979-983
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• 2003

The pharmacokinetic of tolbutamide was studied after the oral administration to normal rabbits or rabbits with mild to medium folate-induced renal failure. The plasma concentrations of tolbutamide were significantly elevated (p<0.05) during 9 to 24 h in rabbits with mild or medium folate-induced renal failure. Consequently, the area under the plasma concentration-time curves (AUC) was significantly higher in mild (p<0.05) and medium (p<0.01) folate-induced renal failure rabbits (i.e., 2906 $\mu$g/mL$.$h for mild renal failure and 4074 $\mu$g/mL$.$h for moderate renal failure) than that in normal rabbits (i.e., 2295 $\mu$g/mL$.$h). The cumulative urinary excretion of tolbutamide was significantly depressed (p<0.05) in medium folate-induced renal failure rabbits (i.e., 3.3 mg) compared with that in normal rabbits (i.e., 5.9 mg). The elimination rate constant (Kel) of tolbutamide was significantly decreased in medium renal failure rabbits (i.e., 0.027 $h^{-1}$) than that in normal rabbits (i.e., 0.044 $h^{-1}$ ); As a result, the terminal half-life of tolbutamide in medium folate-induced renal failure rabbits (i.e., 25.5 h) was significantly longer (p<0.01) than that in normal rabbits (i.e., 15.7 h). The change in pharmacokinetic parameters is consistent with the hypothesis that the alteration is mediated by the depressed metabolic elimination of the drug by the induction of renal failure. Therefore, these observations indicated that the dosage adjustment may be necessary for tolbutamide in patients with renal insufficiency.

• Journal of Soil and Groundwater Environment
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• v.20 no.6
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• pp.103-110
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• 2015

Nitro-aromatic Compounds (NACs) of explosives are structurally non-degradable materials that have an adverse effect to humans and ecosystems in case of emissions in natural due to the strong toxicity. In this study, batch test in the laboratory-scale has been conducted to find some process parameters of alkaline hydrolysis by considering the characteristics of NACs which are unstable in a base status and field application evaluation have been performed on the batch test results. Based on the experimental results of both laboratory and pilot-scale test, the optimum conditions of parameters for the alkaline hydrolysis of soils contaminated with explosives were pH 12.5, above the solid-liquid ratio 1 : 3, above the room temperature and 30 minute reaction time. In these four process parameters, the most important influencing factor was pH, and the condition of above pH 12.0 was necessary for high contaminated soils (more than 60 mg/kg). In the case of above pH 12.5, the efficiency of alkaline hydrolysis was very high regardless of the concentrations of contaminated soils. At pH 11.5, the removal efficiency of TNT was increased from 76.5% to 97.5% when the temperature in reactor was elevated from room temperature to 80℃. This result shows that it is possible to operate the alkaline hydrolysis at even pH 11.5 due to increased reaction rate depending on temperature adjustment. The results found in above experiments will be able to be used in alkaline hydrolysis for process improvement considering the economy.

• Applied Chemistry for Engineering
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• v.16 no.1
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• pp.45-51
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• 2005

$K^+-{\beta}^{{\prime}{\prime}}-Al_2O_3$ in the $K_2O-Li_2O-Al_2O_3$ ternary system was synthesized using aluminum nitrate solution as a starting material. For the synthesis of pure $K^+-{\beta}^{{\prime}{\prime}}-Al_2O_3$, raw materials with chemical composition of $0.84K_2O{\cdot}0.082Li_2O{\cdot}5.2Al_2O_3$ were mixed in solution state. The effects of dispersant and solution-pH were investigated in minimizing the particle size and on the synthesis of pure $K^+-{\beta}^{{\prime}{\prime}}-Al_2O_3$. Ethanol was used for a dispersant, and $NH_4OH$ solution and nitric acid were added for pH adjustment. The solution pH was increased from 1.0 to 7.5 by 0.5 increments. Each sample was calcined at $1200^{\circ}C$ for 2 h and characterized with X-ray diffraction and particle size analyzer. The pH of solution significantly effected both particle size and phase formation, while the addition of ethanol only effected particle size. The synthesis of pure $K^+-{\beta}^{{\prime}{\prime}}-Al_2O_3$ was favored by addition of nitric acid (for pH control).

• Environmental Engineering Research
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• v.11 no.2
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• pp.84-90
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• 2006

UV-catalytic oxidation technique was applied for the treatment of bio-refractory character of the leachate, which is generally present in the form of adsorbable organic halogens (AOX). Destruction of AOX was likely to be governed by pH adjustment, quantitative measurement of oxidants, and the selection of oxidation model type. Peroxide induced degradation ($UV/H_2O_2$) facilitated the chemical oxidation of organic halides in acidic medium, however, the system showed least AOX removal efficiency than the other two systems. Increased dosage of hydrogen peroxide (from 0.5 time to 1.0 time concentration) even did not contribute to a significant increase in the removal rate of AOX. In ozone induced degradation system ($UV/O_3$), alkaline medium (pH 10) favored the removal of AOX and the removal rate was found 11% higher than the rate at pH 3. Since efficiency of the $UV/O_3$ increases with the increase of pH, therefore, more OH-radicals were available for the destruction of organic halides. UV-light with the combination of both ozone and hydrogen peroxide ($UV/H_2O_2$ 0.5 time/$O_3$ 25 mg/min) showed the highest removal rate of AOX and the removal efficiency was found 26% higher than the removal efficiency of $UV/O_3$. The system $UV/H2O_2/O_3$ got the economic preference over the other two systems since lower dose of hydrogen peroxide and relatively shorter reaction time were found enough to get the highest AOX removal rate.

• Journal of Animal Science and Technology
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• v.47 no.6
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• pp.1059-1066
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• 2005

The objective of this study was to investigate the physico-chemical characteristics of chicken breast surimi processed by four times washing (C) and adjustment to pH 3.0 (T1) and pH 11.0 (T2). Water, crude protein, myofibrillar protein and yield of the treatment C were lower compared to other two treatments. Crude fat of T2 was higher than other two treatments. pH, WHC, breaking force and deformation were not different among the treatments. Shear force of T2 was the highest, followed by T1 and C. L* of T2 and a* of T1 were lower than other two treatments. b* of C was the highest, while T2 was the lowest. Brittleness and hardness in textural properties were not different among the treatments. Cohesiveness of T1 was the lowest among three treatments. Springiness and chewiness of T1 and T2 were higher than those of treatment C, respectively. Gumminess of T2 were higher compared to C and T1. Appearance and flavor in sensory evaluation were the highest in T1 and the lowest in C among three treatments. Color, aroma, juiciness, tenderness and overall acceptability were not different among the treatments. In conclusion, physico-chemical quality of chicken breast surimi was the highest in T2 among three treatments.

• YAKHAK HOEJI
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• v.42 no.3
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• pp.284-289
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• 1998

The effect of reaction condition, solvent addition and thermal treatment on the bulk density, crystallinity and chemical properties of the freeze-dried cefazohn sodium was inves tigated to prepare the cefazolin sodium powder for injection with good flowability. Crystalline cefazolin sodium powder with high untapped-bulk density (about 45%) and low compressibility (about 40%) was obtained by solvent addition to the very highly concentrated cefazohn sodium solution followed by subsequent thermal treatment before freeze-drying. The desirable solvent was low substituted alcohol such as isopropyl alcohol and anhydrous ethanol with the final concentration of about 9%. The pH adjustment and nitrogen gas purging during the reaction did not give significant effect on the chemical properties such as content, color, transmittance and pH of the reconstituted cefazolin sodium aqueous solution.

• Journal of the Korean Wood Science and Technology
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• v.23 no.4
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• pp.54-59
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• 1995

This experiment was carried out to evaluate the role of oxalic acid metabolism in the incipient decay of brown rotting, and to investigate the effects of various compositions of culture medium. Until 5days incubation, the amount of oxalic acid produced by Tyromyces palustris was increased, while pH was gradually decreased. The difference in oxalic acid production depending on carbon sources was not significant and the pH adjustment of media did not stimulate the production of oxalic acid. In this experiment, hemicellulose was hydrolyzed with 1% oxalic acid, so it is suggested that nonenzymatic acid hydrolysis of hemicelluloses might be involved in the process of incipient decay of brown-rot fungi.

• KSBB Journal
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• v.9 no.3
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• pp.306-311
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• 1994

Optical resolution of racemic ${\alpha}$-methylbenzylamine was carried out by using Bacillus licheniformis protease in organic media. Enantioselective amidation of racemic amino with an ester as an acyl donor was successfully employed to resolve the racemate. To enhance reaction rate and enantioselectivity, pH-adjustment by lyophilization of enzyme dissolved in buffer, colyophilization with salts or lyoprotectants, selection of solvents and molecular design of esters were investigated. The optimization of the resolution reaction achieved about 30-fold increase in initial reaction rate and about 12-fold increase in enantioselectivity, respectively.

• Journal of Soil and Groundwater Environment
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• v.7 no.3
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• pp.85-94
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• 2002

Overall objective of this study was to evaluate the electrochemical characteristics of fine soils during the electrokinetic(EK) remediation. Zeta potential of kaolinite as a function of solution pH and surfactant concentration was investigated to make a relationship with electroosmotic flow direction and rate. During the EK experiments, pH of pore solution, electroosmotic permeability($k_e$), electric conductivity($\delta_e$) and voltage distribution was measured, respectively, The point of zero charge(PZC) of kaolinite was estimated to be about 4.2 and the zeta potential of kaolinite above PZC was more negative as solution pH increased. Sorption of surfactants on the kaolinite altered the zeta potential of kaolinite. resulting from the variation of electrochemical characteristics of kaolinite surface. hs the EK experiment progressed, low pH was predominant over most of the kaolinite specimen and thus resulted in very low mass and charge flow. The $k_e$ and $\delta_e$ was also affected by the variation of voltage drop across the EK column with time. Results from this study implied that zeta potential of kaolinite affected by the pH variation of pore solution and voltage distribution in soil column played important role in the determination of mass and charge flow during EK process. It was also suggested that pH adjustment or addition of suitable sorbates could alter the electrochemical characteristics of soil surface and thus maintain high mass and charge flow rate with time.

• Korean Journal of Food Science and Technology
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• v.41 no.2
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• pp.167-172
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• 2009

The principal objective of this study was to determine the optimum manufacturing conditions of egg white with high foaming property for the production of angel food cakes. The egg whites were desugarized and powdered at predetermined pHs and drying temperatures. The physicochemical properties of the produced cakes were measured and sensory evaluations were conducted on a 9-point scale. The volume and textural properties of cakes produced from spray-dried egg whites did not differ from those of the cakes prepared from the control egg whites. The pH of batter and the specific gravity of foam and batter with egg white powder at pH 6.74/66.5$^{\circ}C$ did not differ from those of the control, whereas the one prepared with commercial powder lost the characteristics of cake to a significant degree. The overall acceptance scores of egg white powder of pH 6.74/66.5$^{\circ}C$ and commercial powder were 6.25 and 2.33 as compared to the control (6.42). These results indicate that the egg white powder that was desugarized, pH-adjusted to 6.74, and dried at 66.5$^{\circ}C$ might be utilized to prepare angel food cakes with the desirable physicochemical and sensory attributes.