• Korean Journal of Environmental Agriculture
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• v.12 no.3
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• pp.209-218
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• 1993

The behaviour of insectcide ethoprophos (O-ethyl S,S-propyl phosphorodithioate) in soil was investigated. In a laboratory study, the degradation of ethoprophos in soil followed first-order reaction kinetics. The half-life of the insecticide in the soil incubated with 10, 18 and $25^{\circ}C$ was 12.4, 5.5 and 2.5 days, respectively. Arrhenius activation energy was 73.8 KJ/mole. The half-life was 46.4, 17.6 and 6.9 day in the soil with 7, 14 and 19% of soil water content, respectively. The moisture dependence B value in empirical equation was 1.67. The adsorption isotherm for ethoprophos in the soil agreed with freundlich equation. The adsorption distribution coefficient (Kd) was 0.27. In a field study prepared in autumn with undisturbed soil column in a mini-lysimeter system, ethoprophos residues were largely distributed in the top $0{\sim}2cm$ soil layer and moved down to the top 6cm soil layer. Persistence of ethoprophos in field soil was correlated with variation in weather pattern during the period of experiments. The half-life of ethoprophos treated at March and October was about 17 and 5 days, respectively. The ethoprophos woil was degraded up to 90% at 37day after the both treatment. In persistence and mobility of ethoprophos in field soil, the observed data were reasonably corresponded with predicted data by some computer model of pesticide behaviour.

• Korean Journal of Head & Neck Oncology
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• v.10 no.2
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• pp.200-205
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• 1994

Proliferating cell nuclear antgen(PCNA) plays an important role in DNA synthesis in nucleoli and is highly conserved non-histone nuclear protein composed of 261 amino acid. and is considered to correlated with the cells proliferative state, because it is synthesized particulary during the proliferative period of late Gland S-phase. Therefore, PCNA index meaningfully increases in the active or proliferative kinetic cells. By the use of recently developed monoclonal antibodies against PCNA, the immunohistochemical staining methods can make possible. These staining methods are the useful and productive one for ascertaining the cell's proliferating abillity. Moreover, immunohistochemical staining method with a antiPCNA antibody has particulrar advantages as follows. By means of these methods, we can stain the tissue that was already fixed in formalin or paraffin wax. We can see with naked eye that which cell is, where is differentiated through a microscope. Lastly, it maintains the whole tissue architecture and makes a search for the correlation. As we have seen above, the immunohistochemical staining methods for PCNA have been studied as an impotant factor that can find the cell proliferative kinetics in malignancy and biologic behavior of tumors. To investigate of the proliferative activity in thyroid nodule, Authors evaluated cell proliferative activity by immunostaing for PNCA in 45 pathologically confirmed solitary thyroid nodule. The results were as follows. 1) The benign nodules were 25 cases(Adenomatous Goiter: 20 cases, Follicular adenoma: 5 cases) and malignant nodules were 20 cases(Papillary Ca : 14 cases, Follicular Ca : 4 cases, Anaplastic Ca : 2 cases). 2) The Most prevalent age groups were 4th decade(11 cases), and the next group was 5th decade. 3) The average PCNA labelling indices were as follows. Adenomatous goiter(I6.9%), Follicular adenoma(37.6%), papillary Ca(26.3%), Follicular Ca(8.8%) and Anaplastic Ca(86.7%). There were no significant differences in benign(20.4) and malignant nodules (28.8%) except anaplastic Ca(p=0.3226). 4) When the average tumor size 2cm in papillary Ca, the PCNA indices were 26.0% (below 2cm) : 26.6% (above 2cm) (p=0.9642). The PCNA incidies were 23.9% (with lymphatic spread) : 28.7% (without lymphatic spread) (p=0.7056). There were no signlficant differences in the above cases. In conclusion, there were no significant differences in cell proliferative activity by staining for PCNA between benign and malignat nodules except anaplastic Ca.

• Journal of Embryo Transfer
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• v.27 no.1
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• pp.51-55
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• 2012

The objective of this study was to investigate the motility and kinematics of boar sperm that while stored at 4C. The samples of fresh boar semen were place into an extender, Androhep, and stored at $4^{\circ}C$. In three of these samples, cryoprotectants were added. The sperm's motilities and kinematics were evaluated by using microscope (${\times}400$) and the viability status was evaluated by using with eosin staining method. The 5 sample groups are; Goup A:Androhep (extender), stored at $17^{\circ}C$. Group B:Androhep (extender), stored at $4^{\circ}C$. Group C:Androhep (extender), + 3% glycerol (cryoprotectant), stored at $4^{\circ}C$. Group D:Androhep (extender), + 3% DMSO (cryoprotectant), stored at $4^{\circ}C$. Group E:Androhep (extender), + 3% ethylene glycol (cryoprotectant), stored at $4^{\circ}C$. In group A, the sperm's motility was reduced. On day one the sperm's motility was ($85.7{\pm}2.3$) and day 5 the motility was ($43.9{\pm}3.3$). In group B, C and D the sperm's motility were reduced to 0 on day 5. In group E the sperm's percentage of motility decreased. On day one the sperm's motility was ($42.0{\pm}0.5$) and day 5 the motility was ($2.3{\pm}0.3$). When comparing cryoprotectant in samples of boar sperm there is a slight improvement in the results when the use of Androhep Lite (extender), + 3% ethylene glycol (cryoprotectant), stored at $4^{\circ}C$ are used. Based on these results, ethylene glycol can protect sperm from heat shock at $4^{\circ}C$, but not satisfactory level. However, it showed the possibilities of liquid semen preservation at $4^{\circ}C$ by using cryoprotectant.

• Applied Chemistry for Engineering
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• v.25 no.4
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• pp.430-436
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• 2014

Allura Red (AR) is a water-soluble harmful tar-based food colorant (FD & C Red 40). Batch adsorption studies were performed for the removal of AR using bituminous coal based granular activated carbon as adsorbent by varying the operation parameters such as adsorbent dosage, initial concentration, contact time and temperature. Experimental equilibrium adsorption data were analyzed by Langmuir, Freundlich and Temkin isotherms. The equilibrium process was described well by Freundlich isotherm. From determined separation factor ($R_L$), adsorption of AR by granular activated carbon could be employed as effective treatment method. Temkin parameter, B was determined to 1.62~3.288 J/mol indicating a physical adsorption process. By estimation of adsorption rate experimental data, the value of intraparticle diffusion rate constant ($k_m$) increased with the increasing adsorption temperature. The adsorption process were found to confirm to the pseudo second order model with good correlation. Thermodynamic parameters like change of free energy, enthalpy, and entropy were also calculated to predict the nature adsorption in the temperature range of 298~318 K. The negative Gibbs free energy change (${\Delta}G$ = -2.16~-6.55 kJ/mol) and the positive enthalpy change (${\Delta}H$ = + 23.29 kJ/mol) indicated the spontaneous and endothermic nature of the adsorption process, respectively.

• Applied Chemistry for Engineering
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• v.28 no.5
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• pp.597-600
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• 2017

$(C_{10}H_8N_2H)_2Cr_2O_7$ was synthesized by reacting 4,4'-bipyridine and chromium (VI) trioxide. The structure of the product was characterized with FT-IR (infrared spectroscopy) and elemental analysis. The oxidation of benzyl alcohol using $(C_{10}H_8N_2H)_2Cr_2O_7$ in various solvents showed that the reactivity increased with the increase of the solvent dielectric constant, in the order of DMF (N,N'-dimethylformamide) > acetone > chloroform > cyclohexane. In the presence of DMF, an acidic catalyst such as $H_2SO_4$ $(C_{10}H_8N_2H)_2Cr_2O_7$ oxidized benzyl alcohol (H) and its derivatives ($p-OCH_3$, $m-CH_3$, $m-OCH_3$, m-Cl, $m-NO_2$). Electron donating substituents accelerated the reaction rate, whereas electron acceptor groups retarded the reaction rate. Hammett reaction constant (${\rho}$) was -0.70 (308 K). The observed experimental data were used to rationalize the hydride ion transfer in the rate determining step.

• Korean Journal of Food Science and Technology
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• v.35 no.3
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• pp.417-422
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• 2003

The onions are considered to be a favorable functional source of beverage because they contain much sugar and various nutrients, and they are juicy vegetable. Recently, consumers have a new trend to take functional foods with health benefits. To meet this need, this study was the basic research to establish a manufacturing process of functional onion beverage by glucose oxidase. Glucose oxidase catalyzes reaction of glucose oxidation and makes generation of gluconic acid. Kinetics of the reaction was also investigated, and maximum glucose consumption rate $(V_{max})$ of $26.1{\times}10^{-2}\;g/L{\cdot}min$ and $K_m$ of 5.84 g/L were obtained. Optimum conditions were obtained when the glucose oxidase catalyzed reaction was carried out at temperature of $25^{\circ}C$, agitation rate of 450 rpm and aeration rate of 4 vvm in a 2.5 L jar fermentor. Finally, the enzyme reactor was 10-times scaled up and a similar glucose oxidation performance was achieved in the scaled-up reactor.

• Korean Journal of Food Science and Technology
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• v.35 no.1
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• pp.23-27
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• 2003

The effects of temperature and pH on color deterioration of anthocyanin in Schizandra fruit (Schizandra chinensis fructus) were determined with temperature range of $80{\sim}100^{\circ}C$ and pH range of $2.0{\sim}5.0$. Browning index was used as an index of color deterioration of crude anthocyanin extract from Schizandra fruit. As pH of crude anthocyanin extract was increased, color deterioration was accelerated, showing pH-dependency of thermal stability of anthocyanin extract from Schizandra fruit. Anthocyanin degradation could be modeled as a second-order rate reaction, with rate of $3.2{\times}10^{-3}\;h^{-1}\;(pH\;2.0){\sim}4.1{\times}10^{-3}\;h^{-1}\;(pH\;5.0)\;at\;100^{\circ}C$. Temperature dependence of deterioration was described by the Arrhenius relationship. Activation energies for pH $2.0{\sim}5.0$ ranged from $24.87{\sim}42.54\;kJ/mol^{-1}$.

• Korean Journal of Food Science and Technology
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• v.22 no.7
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• pp.799-801
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• 1990

Of the several methods proposed for decreasing toxicity of Paralytic shellfish poison(PSP) from intoxicated shellfish, heat treatment has been most popular, although a large percentage of the incidents of PSP illness have been related to the ingestion of cooked shellfish. The purpose of this study was to determine the kinetics of PSP destruction at various temperatures. The homogenate of intoxicated blue mussel(Mytilus edulis) was heated at temperature ranging from $90\;to\;121^{\circ}C$ and toxicities measured in samples heated for various time intervals. The rate constant(k) per second was $3{\times}10^{-4},\;at\;90^{\circ}C,\;4.98{\times}10^{-4},\;at\;100^{\circ}C,\;7.38{\times}10^{-4},\;at\;116^{\circ}C,\;and\;8.38{\times}10^{-4},\;at\;121^{\circ}C,\;$. By the Arrhenius equation, the decimal reduction time(D-value) was $121min.\;at\;90^{\circ}C,\;82min,\;at\;100^{\circ}C,\;58min.\;at\;116^{\circ}C\;and\;53min.\;at\;121^{\circ}C$. The z-value, activation energy($E_a\;and\;Q_{10}$) was $72^{\circ}C,\;3.9{\times}10^7(J/kg\;mol)$ and 1.39, respectively.

• Journal of the Korean Society of Food Science and Nutrition
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• v.43 no.7
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• pp.1068-1074
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• 2014

This study investigated the quality characteristics of baked rice cake added with maltitol syrup. The hardness, adhesiveness, cohesiveness, gumminess, and chewiness of baked rice cake significantly decreased (P<0.05) according to the level of added maltitol syrup. Hunter's color values of baked rice cake did not differ significantly according to the level of added maltitol syrup. Sensory evaluation indicated that appearance, moistness, chewiness, hardness, and overall acceptance of baked rice cake prepared with added maltitol syrup were improved compared to those of baked control rice cake. Hunter's color values and texture properties of baked rice cake added with 10% maltitol syrup were compared with those of baked control rice cake during storage at room temperature for 3 days. Hunter's color L values of baked rice cake decreased during storage, whereas a and b values increased. The rate of hardness increase in baked rice cake with maltitol syrup was lower than that in baked control rice cake during storage. The Avrami exponents (n) of baked control rice cake and baked rice cake added with 10% maltitol were 2.418 and 2.098, respectively. The time constants (1/k) of the former and latter were 43.860 and 60.976, respectively. Overall, addition of 10% maltitol syrup improved the texture, sensory properties, and retarding retrogradation of baked rice cake.

• Korean Chemical Engineering Research
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• v.46 no.6
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• pp.1113-1118
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• 2008

Characteristics of reduction properties and carbon deposition of $CuFe_2O_4$ and $Fe_3O_4$ were investigated by using TGA, XRD, SEM, TEM and gas analysis at $900^{\circ}C$. XRD analyses indicated that the reduced $Fe_3O_4$ was composed of Fe, graphite and $Fe_3C$ phases. In contrast, the reduced $CuFe_2O_4$ did not show the graphite or $Fe_3C$ phases. It was observed by SEM analysis that the surface of the $Fe_3O_4$ was completely covered with carbon, after methane partial oxidation. From gas analysis, $CuFe_2O_4$ showed much higher methane conversion and reduction kinetics as compared to the $Fe_3O_4$ under the same reaction conditions and the estimated carbon deposition amounts on the reduced $CuFe_2O_4$ was much lower than those on the reduced $Fe_3O_4$ during the syngas production process. It was found by TEM that carbon on the reduced $Fe_3O_4$ particles has a platelet shape.