• Korean Journal of Food Science and Technology
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• v.20 no.3
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• pp.338-343
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• 1988

Selected kinetic parameters and degree of hydrolysis(DH) were measured using commercial proteases(trypsin, alcalase and pronase) to study the affinity of these enzymes to 7S and 11S soy proteins. Electrophoretic patterns of the hydrolysates were also investigated. In general, the order of affinity between the proteins and the proteases was 11S(protein-rich fraction)and 7S PRF for unheated proteins, and 7S PRF and 11S PRF for preheated proteins. Substrate inhibition was present at a substrate concentration of 1.5% or higher when preheated protein was used as the substrate. The maximum DH values of alcalase were obtained from 7S PRF(60%) and 11S PRF(80%) at 1 hr hydrolysis, respectively. Trypsin hydrolyses did not affect 11S soy protein but the acidic subunits in contrast to alcalase and pronase hydrolyses which changed almost all subunits. Alcalase hydrolysis induced distinct changes on 2S soy protein.

• Journal of Nuclear Fuel Cycle and Waste Technology(JNFCWT)
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• v.2 no.3
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• pp.201-209
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• 2004

Important operation parameters and performance of a high temperature ceramic candle filter system were evaluated through a series of demonstration tests at a pilot-scale vitrification plant. At the initial period of each test, due to the growth of dust cake on the surface of ceramic candles, the pressure drop across the filter media increased sharply. After that it became stable to a certain range and varied continuously proportion to the face velocity of off-gas. On the contrary, at the initial period of each test, the permeability of filter element decreased rapidly and then it became stable. Back flushing of the filter system was effective under the back flushing air pressure range of 3∼5 bar. Based on the dust concentrations measured by iso-kinetic dust sampling at the inlet and outlet point of HTF, the dust collection efficiency of HTF evaluated. The result met the designed performance value of 99.9%. During the demonstration tests including a hundred hour long test, no specific failure or problem affecting the performance of HTF system were observed.

• International Journal of Highway Engineering
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• v.19 no.6
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• pp.67-74
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• 2017

PURPOSES : In this study, a three-dimensional nonlinear finite element analysis (FEA) model for airport concrete pavement was developed using the commercial program ABAQUS. Users can select an analysis method and set the range of input parameters to reflect actual conditions such as environmental loading. METHODS : The geometrical shape of the FEA model was chosen by considering the concrete pavement located in the third-stage construction site of Incheon International Airport. Incompatible eight-node elements were used for the FEA model. Laboratory test results for the concrete specimens fabricated at the construction site were used as material properties of the concrete slab. The material properties of the cement-treated base suggested by the Federal Aviation Administration(FAA) manual were used as those of the lean concrete subbase. In addition, preceding studies and pavement evaluation reports of Incheon International Airport were referred for the material properties of asphalt base and subgrade. The kinetic friction coefficient between the concrete slab and asphalt base acquired from a preceding study was used for the friction coefficient between the layers. A nonlinear temperature gradient according to slab depth was used as an input parameter of environmental loading, and a quasistatic method was used to analyze traffic loading. The average load transfer efficiency obtained from an Heavy falling Weight Deflectomete(HWD) test was converted to a spring constant between adjacent slabs to be used as an input parameter. The reliability of the FEA model developed in this study was verified by comparing its analysis results to those of the FEAFAA model. RESULTS : A series of analyses were performed for environmental loading, traffic loading, and combined loading by using both the model developed in this study and the FEAFAA model under the same conditions. The stresses of the concrete slab obtained by both analysis models were almost the same. An HWD test was simulated and analyzed using the FEA model developed in this study. As a result, the actual deflections at the center, mid-edge, and corner of the slab caused by the HWD loading were similar to those obtained by the analysis. CONCLUSIONS : The FEA model developed in this study was judged to be utilized sufficiently in the prediction of behavior of airport concrete pavement.

• Radiation Oncology Journal
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• v.11 no.2
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• pp.219-225
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• 1993

The evaluation of radiation-induced DNA double strand breaks (DSB) was made following irradiation of human lymphocytes, murine lymphocytes and EL-4 leukemia cells over a wide dose range of $^{60}Co\;{gamma}-rays.$ In lipopolysaccharide (LPS) or phytohemagglutinin (PHA)-stimulated murine lymphocytes, the slopes of the stand scission factor (SSF) revealed that lymphocytes with LPS increased DNA DSB formation by a factor of 1.432 (p<0.005). Furthermore, strand break production was relatively inefficient in the T lymphocytes compared to the B lymuhocytes. And EL-4 leukemia cells were found to form significantly more DNA DSB to a greater extent than normal lymphocytes (p<0.005). The in vitro studies of the intrinsic radiosensitivity between human lymphocytes and murine lymphocytes showed similar phasic kinetics. However, murine lymphocytes were lower in DNA DSB formation and higher in the relative radiation dose of 10 percent DNA strand breaks at 3.5 hours following ${gamma}-irradiation$ than human lymphocytes. Though it is difficult to interpret these results, these differences may be result from environmental and genetic factors. From our data, if complementary explanations for this difference will be proposed, the differences in the dose-effect relationship for the induction of DSB between humans and mice must be related to interspecies variations in the physiological condition of the peripheral blood in vitro and not to differences in the intrinsic radiation sensitivity of the lymphocytes. These results can be estimated on the basis of dose-effect correlation enabling the interpretation of clinical response and the radiobiological parameters of cytometrical assessment.

• Proceedings of the Korean Vacuum Society Conference
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• 2011.02a
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• pp.407-408
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• 2011

Natural boron consists of two stable isotopes 10B and 11B with natural abundance of 18.8 atom percent of 10B and 81.2 atom percent of 11B. The thermal neutron absorption cross-section for 10B and 11B are 3837 barn and 0.005 barn respectively. 10B enriched specific compounds are used for control rods and as a reactor coolant additives. In this work 2 methods for boron enrichment were analysed: 1) Gas irradiation in static conditions. Dissociation occurs due to multiphoton absorption by specific isotopes in appropriately tuned laser field. IR shifted laser pulses are usually used in combination with increasing the laser intensity also improves selectivity up to some degree. In order to prevent recombination of dissociated molecules BCl3 is mixed with H2S 2) SILARC method. Advantages of this method: a) Gas cooling is helpful to split and shrink boron isotopes absorption bands. In order to achieve better selectivity BCl3 gas has to be substantially rarefied (~0.01%-5%) in mixture with carrier gas. b) Laser intensity is lower than in the first method. Some preliminary calculations of dissociation and recombination with carrier gas molecules energetics for both methods will be demonstrated Boron separation in SILARC method can be represented as multistage process: 1) Mixture of BCl3 with carrier gas is putted in reservoir 2) Gas overcooling due to expansion through Laval nozzle 3) IR multiphoton absorption by gas irradiated by specifically tuned laser field with subsequent gradual gas condensation in outlet chamber It is planned to develop software which includes these stages. This software will rely on the following available software based on quantum molecular dynamics in external quantized field: 1) WavePacket: Each particle is treated semiclassicaly based on Wigner transform method 2) Turbomole: It is based on local density methods like density of functional methods (DFT) and its improvement- coupled clusters approach (CC) to take into account quantum correlation. These models will be used to extract information concerning kinetic coefficients, and their dependence on applied external field. Information on radiative corrections to equation of state induced by laser field which take into account possible phase transition (or crossover?) can be also revealed. This mixed phase equation of state with quantum corrections will be further used in hydrodynamical simulations. Moreover results of these hydrodynamical simulations can be compared with results of CFD calculations. The first reasonable question to ask before starting the CFD simulations is whether turbulent effects are significant or not, and how to model turbulence? The questions of laser beam parameters and outlet chamber geometry which are most optimal to make all gas volume irradiated is also discussed. Relationship between enrichment factor and stagnation pressure and temperature based on experimental data is also reported.

• Journal of Navigation and Port Research
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• v.30 no.8 s.114
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• pp.649-655
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• 2006

Waves progressing into the coastal area can be amplified, swashed and overtopped by a wave overtopping control structure, and it converts the kinetic energy of the waves to the potential energy with a hydraulic head above the mean sea level by conserving the overflow in a reservoir. Then the potential energy in the form of hydraulic head can be converted to electric power utilizing extremely low-head hydraulic turbine. This study aims to find the most optimal shape of wave overtopping structure which maximizes overtopping volume rate of sea water. Laboratory experiments for the performance evaluation of wave overtopping control structures were carried out in three dimensional wave tank, and the three dimensional structure models with planar wave concentration shapes(B/b) were manufactured into five classes, which were optimized by cross sectional parameters of the structure, ie, length of ramp(l), gradient of inclined ramp($cot{\phi}$) and freeboard height of the wave overtopping structure($h_e$) proposed by Shin and Hong(2005). The wave overtopping discharges were investigated with 20 incident wave conditions and wave directions of $0^{\circ},\;15^{\circ},\;30^{\circ}$.

• Journal of fish pathology
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• v.28 no.1
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• pp.43-51
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• 2015

The pharmacokinetic properties and residue levels of amoxicillin (AMOX) were studied after intramuscular injection to cultured olive flounders ($100{\pm}50g$), Paralichthys olivaceus. For pharmacokinetic studies, AMOX of 20 to 80 mg/kg body weight was administered at $17{\pm}2^{\circ}C$ or $22{\pm}2^{\circ}C$ and AMOX concentrations were determined in plasma, the liver, and the kidney by HPLC-UVD. Plasma samples were assessed at 0.25, 0.5, 1, 3, 6, 12, 24, 48, 72, 96, 168 hours post-dose, whereas liver and kidney concentrations were measured at 0.25 to 48 hours post-dose. The kinetic profiles of AMOX were analyzed by fitting to a 2-compartmental model with PKSolver program. The following parameters were obtained for a single dosage of 20, 40 and 80 mg/kg of body weight at $22^{\circ}C$ and 20 and 40 mg/kg of body weight at $17^{\circ}C$ in plasma, liver and kidney, respectively: $C_{max}$ (the peak concentration)= $27.23-257.36{\mu}g/m{\ell}$, $5.49-41.65{\mu}g/g$, $16.75-129.31{\mu}g/g$; $t_{max}$ (the time for peak concentration)= 0.05-0.91, 1.36-3.28, 1.95-4.49 h. For residue studies, AMOX of 40 and 400mg/kg was administered, and muscle samples were taken at 2, 5, 7, 14 and 21 days post-dose. The residueof AMOX in the muscle were found under the MRLs (maximum residue levels) within 7 days for the two doses.

• Journal of fish pathology
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• v.22 no.1
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• pp.91-95
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• 2009

The pharmacokinetic properties of oxytetracycline (OTC) were studied after intramuscular injection to cultured olive flounder, Paralichthys olivaceus. Plasma concentrations of OTC were determined after dosage of 12.5, 25 and 50 ㎎/㎏ body weight in olive flounder (average 600 g, $23{\pm}1{^{\circ}C}$). Plasma samples were taken at 3, 5, 10, 15, 24, 32, 48, 72, 120, 168, 240 and 360 h post-dose. With 25 and 50 ㎎/㎏, the peak plasma concentrations of OTC, which attained at 5 h post-dose, were 0.99 and 1.49 $\mu{g}/m\ell$, respectively. However, the peak plasma concentration of 12.5 ㎎/㎏ was 0.35 $\mu{g}/m\ell$ after 10 h post-dose. Plasma concentrations of OTC were not measurable at 360 h post-dose in all doses. The kinetic profile of absorption, distribution and elimination of OTC in plasma were analyzed fitting to a 1-compartment model by Win-Nonlin program. The following parameters were calculated for 12.5, 25 and 50 ㎎/㎏ body weight, respectively: AUC (the area under the concentration-time curve)?D���D24.98, 44.67 and 50.45 $\mu{g}$ $h/m\ell$ $T_{1/2}$ (half-life) ?D���D0.42, 0.59 and 0.41 h; $T_{max}$ (time for maximum concentration)?D���D8.46, 6.34 and 2.66 h; $C_{max}$ (maximum concentration)?D���D0.30, 0.63 and 1.13 $\mu{g}/m\ell$.

• Polymer(Korea)
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• v.39 no.2
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• pp.210-218
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• 2015

The reaction behavior of rigid polyurethane foams were studied on the effects of gelling catalysts of amine type, such as; dimethylcyclohexyl amine (DMCHA) and of potassium type, such as; potassium octoate (PO). Rigid polyurethane foams were provided with polymeric 4,4'-diphenylmethane diisocyanate, polyester polyol, silicone surfactant, blowing agent and a few gelling catalysts. As the contents of catalyst, DMCHA increased from 0 to 2.0 g, the reaction time decreased from ca. 330 to ca. 35 sec and due to the exothermic reaction, the maximum temperature increased from ca. 217 to ca. $234^{\circ}C$, respectively. As the contents of PO increased from 0 to 2.5 g, the reaction time decreased from ca. 79 to ca. 38 sec and the maximum temperature increased from ca. 182 to ca. $271^{\circ}C$, respectively. The kinetic parameters were calculated and the conversions were based on the temperature rising method of adiabatic process. As the content of DMCHA increased, the rate constant $k_0$ increased. But in the case of PO catalyst, $k_0$ did hardly depend upon its amount, and showed us similar reaction rate constants.

• Journal of Microbiology and Biotechnology
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• v.22 no.3
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• pp.292-300
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• 2012

We report the expression, purification, and characterization of L-asparaginase (AnsA) from Rhizobium etli. The enzyme was purified to homogeneity in a single-step procedure involving affinity chromatography, and the kinetic parameters $K_m$, $V_{max}$, and $k_{cat}$ for L-asparagine were determined. The enzymatic activity in the presence of a number of substrates and metal ions was investigated. The molecular mass of the enzyme was 47 kDa by SDS-PAGE. The enzyme showed a maximal activity at $50^{\circ}C$, but the optimal temperature of activity was $37^{\circ}C$. It also showed maximal and optimal activities at pH 9.0. The values of $K_m$, $V_{max}$, $k_{cat}$, and $k_{cat}/K_m$ were $8.9{\pm}0.967{\times}10^{-3}$ M, $128{\pm}2.8$ U/mg protein, $106{\pm}2s^{-1}$, and $1.2{\pm}0.105{\times}10^4M^{-1}s^{-1}$, respectively. The L-asparaginase activity was reduced in the presence of $Mn^{2+}$, $Zn^{2+}$, $Ca^{2+}$, and $Mg^{2+}$ metal ions for about 52% to 31%. In addition, we found that $NH_4{^+}$, L-Asp, D-Asn, and ${\beta}$-aspartyl-hydroxamate in the reaction buffer reduced the activity of the enzyme, whereas L-Gln did not modify its enzymatic activity. This is the first report on the expression and characterization of the L-asparaginase (AnsA) from R. etli. Phylogenetic analysis of asparaginases reveals an increasing group of known sequences of the Rhizobial-type asparaginase II family.