• Journal of the Korean Chemical Society
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• v.32 no.3
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• pp.227-232
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• 1988

A kinetic study was made to determine the mechanism of the aquation of $cis-[Co(en)_2(NH_3)Cl]^{2+}\;in\;Hg^{2+}$ aqueous solution. The progress of reaction was followed UV/vis-spectrophotometrically by a measurement of the absorbance at a specific wave length (530nm) of $cis-[Co(en)_2(NH_3)Cl]^{2+}$ as a function of time. The experimental results have shown that the reaction rate is dependent upon the concentration of $Hg^{2+}$ that act as a catalyst. And it was found that the overall reaction proceed with second order, first order with respect to Co(III) complex and $Hg^{2+}$. Activation parameters, ${\Delta}H^{\neq}\;and\;{\Delta}S^{\neq}$, were obtained as 12.9 kcal/mol and -19.3 e.u., respectively. We have proposed a plausible reaction mechanism which is consistent with the observed rate equation.

• Food Science of Animal Resources
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• v.26 no.1
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• pp.20-27
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• 2006

Effects of addition level of sodium chloride (NaCl) on gel properties of surimi-like pork (SLP) were investigated. Porcine semimembranosus muscle was used to manufacture SIP contained 1, 2, 3 and 4% NaCl to measure moisture content, pH, color, gel strength, micro-structure and sensory evaluation. The pH and moisture content of SLP were decreased as increasing of NaCl level. However, the gel strength of SLP was increased with increasing of NaCl level. Values of yellowness and chroma were lower in SLP of 2% and 3% NaCl compared with those of 1% and 4% NaCl. Amorphus protein particles size in micro-structure of SLP was decreased and coagulated as increasing level of NaCl. SLP of 1% NaCl had a structure formed by aggregates of densely packed globular proteins and arranged in clusters, whereas a well-structured matrix with a highly interconnected network of strand was observed in SLP of 4% NaCl. Result suggested that the increasing gel strength with NaCl level might be due to lower moisture content and denser micro-structure of gel.

• Korean Journal of Crystallography
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• v.9 no.1
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• pp.6-10
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• 1998

The complex[Cu(L)](ClO4)2 (1) (L:3,5,10,12-Tetramethyl-1,4,8,11-tetraazacyclotetradecane) has been synthesized and structurally characterized. The complex 1 crystallizes in the monoclinic system, space group P21/n with cell parameters a=8.208(2)Å, b=13.339(6) Å, c=10.752(5) Å, β=111.02(4)˚ Z=2. Least-squares refinement of 1 led to a R(RW)factor of 0.073 (0.142) for 617 observed reflections of F0>40(F0). The crystal structure of 1 has a square-planar geometry and adopts the trans-III conformation.

• Food Science of Animal Resources
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• v.28 no.5
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• pp.567-573
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• 2008

This study investigated the effects of sodium chloride, potassium chloride, potassium lactate and calcium ascorbate on the physico-chemical and sensory characteristics of sodium-reduced pork patties. Pork patties were prepared in 4 ways: T1 (control, 1.0% NaCl), T2 (0.6% NaCl, 0.4% KCl), T3 (0.7% NaCl, 0.3% potassium lactate) and T4 (0.7% NaCl, 0.3% calcium ascorbate). The pH, cooking loss, total plate counts, TBARS (2-thiobarbituric acid reactive substances), surface color (L, a, b) and sensory characteristics were evaluated. The partial substitution of NaCl with KCl and calcium ascorbate decreased the cooking loss and TBARS values, and enhanced microbial stability. The partial substitution of NaCl with potassium lactate significantly decreased TBARS values and enhanced microbial stability, but significantly increased cooking loss compared to the control after 1 and 4 days of storage. However, the surface color and sensory characteristics were not affected by any of the treatments.

• Journal of Environmental Science International
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• v.17 no.2
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• pp.233-237
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• 2008

The objective of this study was conducted to evaluate the effects of poultry litter amendments on pH and soluble reactive phosphorus (SRP) in poultry litter. Two laboratory studies were conducted for 42 d in Exp. 1 and for 10 d in Exp. 2, respectively. The poultry litter was treated with various amendments which included 4 g fly ash and 4 g $AlCl_3\;(AlCl_36H_2O)/100g$ litter in Exp. 1 and 4 g alum$(Al_2(SO_4){_3}\;14H_2O)$, 8 g alum, 8.66 g liquid alum, and 17.3 g liquid alum/100 g litter in Exp. 2; untreated litter served as controls. There were no differences in pH between control and T1(4 g fly ash) and SRP contents between T1(4 g fly ash) and T2(4 g $AlCl_3$) in Exp. 1. A significant difference in pH and SRP contents in Exp. 2 was observed among all treatments(P< 0.05). In experiment 1, T1(4 g fly ash) and T2(4 g $AlCl_3$) at 42 d decreased SRP in litter by 47.1% and 62.6% of that from litter alone, respectively. In experiment 2, T1(4 g alum), T2(8.66 g liquid alum), T3(8 g alum), and T4(17.3 g liquid alum) treatments at 10 days reduced SRP contents by up to 36.2%, 62.9%, 87.0%, and 83.9%, respectively, when compared with the controls. Decrease in SRP contents was chiefly associated with reduction in litter pH. These results indicate that use of various litter amendments to limit P solubility has potential and should be pursued as a means of reducing soluble reative phosphorus during short term.

• Journal of Korea Foundry Society
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• v.20 no.1
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• pp.38-45
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• 2000

The remelting for recycling or thin aluminum scrap, such as aluminum chip generally involves melting of these pieces submerged in molten salt flux. In this study, the effects of salt flux compositions and alloying elements on the aluminum dropletscoalescence and oxide film removal were studied in 99.8%Al, Al-1.01%Cu, Al-1.03%Si, and Al-1.38%Mg alloys as a function of holding time at $740^{\circ}C$ Salt fluxes based on NaCl-KCl(1:1) with addition of 5wt.% fluorides(NaF, $Na_3AlF_6$, $CaF_2$) or 5 wt.% chloride($MgCl_2$, $AlCl_3$) were used. The experimental results show that NaCl-KCl(1:1) with addition of 5 wt.% fluorides exhibits better coalescence ability than that with chlorides. The oxide film is not removed by NaCl-KCl(1:1) with addition of 5 wt.%chlorides, while it is removed by NaCl-KCl(1:1) with addition of 5 wt.% fluorides. The aluminum droplets coalescence and oxide film removal by salt fluxes are related to interfacial tension tension between metal and salt flux.

• Journal of the Korean Society of Combustion
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• v.5 no.1
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• pp.7-18
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• 2000

Numerical simulations of counterflow non-premixed $CH_4/C_2HCl_3/Air$ flames added 8%(by volume) C2HCl3 on the fuel side are conducted at atmospheric pressure using a detailed chemical reaction mechanism in order to understand the effect of strain rates. A detailed sensitivity analysis is also performed in order to assess the relative influence of each reaction on the flame established at a strain rate of 200s-1. The structure of flames (i.e., temperature, velocity, and concentration of species) established at both a strain rate of 150s-1 and 300s-1 are investigated. As the strain rate increases, the "flame zone" is restricted to a narrower range and the position of maximum temperature is shifted to the fuel side. The concentrations of major species, H2O, CO, H2, HCl, Cl2, and Cl are decreased with increased strain rate. The reaction involving chlorine, CH4 + Cl $\rightarrow$ CH3 + HCl, instead of the reaction, CH4 + H $\rightarrow$ CH3 + H2 influences the consumption of methane. C2HCl3 + OH $\rightarrow$ CHCl2 + CHOCl and HCl + OH $\rightarrow$ H2O + Cl, are major reactions, through which OH radicals are consumed.

• Journal of Environmental Health Sciences
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• v.27 no.1
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• pp.63-68
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• 2001

A laboratory experiment was performed to invstigate the nitrate removal using FeCl$_3$ -treated activated carbon. Iron chloride(III) was coated onto the surface of activated carbon. The removal efficiency of nitrate was increased with increasing of FeCl$_3$ was used for coating material. About 22~26mg of Fe per unit g of activated carbon was adsorbed. The nitrate removal was not affected by the pH under the experiment range of pH, but the pH value in solution decrease to 3.5~4.0 after reaction. The removal efficiency of nitrate was increased with increasing of dosage of adsorbents. Ammonia was not detected and the Fe concentration as low as 0.22mg/$\ell$ was desorbed from the adsorbents. The adsorbents was regenerated using KCl solution, and recovery was 76.6% at 1 M of KCl. The adsorption of nitrate by FeCl$_3$-treated activated carbon followed the Freundlich isotherm equation and the Freundlich constant, 1/n, was 0.346. These results showed that the FeCl$_3$-treated activated carbon could serve as the basis of a useful nitrate removal.

• Korean Journal of Microbiology
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• v.38 no.2
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• pp.74-80
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• 2002

The purpose of this work was to investigate the characterization and sequence of catechol 1,2-dioxygenase (Cl,2O) purified from Acinetobacter sp. KS-1 which was grown on benzoate as a sole carbon source. Cl,2O demonstrated its enzyme activity to catechol and 4-methylcatechol. The optimum temperature of Cl,2O was $35^{\circ}C$, and the optimal pH was in the range from pH 7.5 to 9.0. $Ag^{+}$, $Hg^{+}$, and $Cu^{2+}$ showed inhibitory effect on the activity of Cl,2O. Molecular weight of the enzyme was determined to approximately 36 kDa by SDS-PAGE and 7-terminal amino acid sequence of Cl,2O was analyzed as $^{1}MNYQQIDALVKQMNVDTAKG^{20}$and exhibited 95% sequence homology with that of Cl,2O from Acinetobacter radioresistens In addition, trypsin digestion and peptide mapping were performed for internal sequencing analysis. Molecular weights of three digested peptide fragments were analyzed as 966.3 Da, 1933.8 Da and 2081.7 Da by MALDI-TOF, which were matched with each internal sequences $^{1}SQSDFNLRR^{9}\, ^{1}HGNRPSHVHYFNSAPGYR^{18}\, ^{1}TIEGPLYVAGAPESVGFAR^{19}$) of. A. radioresistens. PCR product was amplified with the degenerated primers derived from N-terminal and each internal amino acid sequences.

• Journal of Powder Materials
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• v.26 no.4
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• pp.282-289
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• 2019

Ti has received considerable attention for aerospace, vehicle, and semiconductor industry applications because of its acid-resistant nature, low density, and high mechanical strength. A common precursor used for preparing Ti materials is $TiCl_4$. To prepare high-purity $TiCl_4$, a process based on the removal of $VOCl_3$ has been widely applied. However, $VOCl_3$ removal by distillation and condensation is difficult because of the similar physical properties of $TiCl_4$ and $VOCl_3$. To circumvent this problem, in this study, we have developed a process for $VOCl_3$ removal using Cu powder and mineral oil as purifying agents. The effects of reaction time and temperature, and ratio of purifying agents on the $VOCl_3$ removal efficiency are investigated by chemical and structural measurements. Clear $TiCl_4$ is obtained after the removal of $VOCl_3$. Notably, complete removal of $VOCl_3$ is achieved with 2.0 wt% of mineral oil. Moreover, the refined $TiCl_4$ is used as a precursor for the synthesis of Ti powder. Ti powder is fabricated by a thermal reduction process at $1,100^{\circ}C$ using an $H_2-Ar$ gas mixture. The average size of the Ti powder particles is in the range of $1-3{\mu}m$.