• Microbiology and Biotechnology Letters
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• v.19 no.2
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• pp.186-192
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• 1991

It is very important to have a good kinetic model which considers the effects of both ammonium and glucose for the control and optimization of the poly-${\beta}$-hydroxybutyrate (PHB) fermentation. A kinetic model for the growth of Alcaligenes eutrophus and the biosynthesis of PHB under both ammonium and glucose limitation was proposed. Growth rate of residual biomass was expressed as a function of concentrations of residual biomass, glucose and ammonium having glucose inhibition. PHB production rate was expressed as a function of concentrations of residual biomass, glucose, ammonium and PHB content having ammonium and product inhibitions. Novel approaches were made to estimate the parameters in the model equations which considered two limiting substrates. Model parameters were evaluated by graphical and simplex methods. The proposed kinetic model fitted the data very well.

• Journal of Powder Materials
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• v.22 no.1
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• pp.32-38
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• 2015

The effect of heat treatment environment on the microstructure and properties of tantalum coating layer manufactured by kinetic spraying was examined. Heat treatments are conducted for one hour at $800^{\circ}C$, $900^{\circ}C$, and $1000^{\circ}C$ in two different environments of vacuum and Ar gas. Evaluation of microstructure and physical properties are conducted. High density ${\alpha}$-tantalum single phase coating layer with a porosity of 0.04% and hardness of 550 Hv can be obtained. As heat treatment temperature increases, porosity identically decreases regardless of heat treatment environment (vacuum and Ar gas). Hardness of heat treated coating layer especially in Ar gas environment deceases from 550 Hv to 490 Hv with increasing heat treatment temperature. That in vacuum environment deceases from 550 Hv to 530 Hv. The boundary between particles became vague as heat treatment temperature increases. Oxygen distribution of tantalum coating layer is minute after heat treatment in vacuum environment than Ar gas environment.

• International Journal of Contents
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• v.9 no.1
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• pp.60-64
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• 2013

This study was performed for two of specific reasons, one is for exercise development for improving stroke patient's muscle power, balance and gait and, after verifying the effect of the exercise, the other is for showing that the appling this exercise was more effective on hemi-plegic stroke patients into the clinical trial. The subjects of this study were hemi-plegic patients by stroke, 51 patients were picked up, who were agreed with this research. Close kinetic chain leg exercise using mirrors was applied to study group I, Close kinetic chain leg exercise without mirrors was applied to study group II and general physical therapy was applied to comparison group. The results of this study are as follows. The difference of the groups, study group I showed more effective than study group II on checking rectus femoris, vastus lateralis, biceps femoris, Korean version of Berg Balance Scale, Center of pressure, Functional gait assessment. In this study, Close kinetic chain leg exercise showed more effective and significant on improving for muscle power, balance and gait on stroke patients. Especially, doing exercise using mirrors is considered as more effective method than without mirrors.

• Korean Journal of Food Science and Technology
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• v.29 no.3
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• pp.497-501
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• 1997

Kinetic parameters on heat-induced color changes of anthocyanin pigment from purple sweet potato were determined in the temperature range of $121{\sim}141^{\circ}C$. Color change determined by a browning index $(A_{532}\;nm/A_{420}\;nm)$ followed second order reaction kinetics. Activation energy values of purple sweet potato pigment solutions of pH 2.0, 3.0, 4.0 and 5.0 were 69.57, 76.68, 81.07 and 92.98 kJ/mol, respectively, indicating that temperature dependency of the reaction increased with pH. Apparent kinetic compensation effect between preex-ponential factor and activation energy value was observed.

• Nuclear Engineering and Technology
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• v.49 no.4
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• pp.700-709
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• 2017

This work looks at the effect of changes in kinetic parameters on simultaneous reactivity insertions and beam tube flooding in a typical material testing reactor-type research reactor with low enriched high density ($U_3Si_2-Al$) fuel. Using a modified PARET code, various ramp reactivity insertions (from $0.1/0.5 s to $1.3/0.5 s) plus beam tube flooding ($0.5/0.25 s) accidents under uncontrolled conditions were analyzed to find their effects on peak power, net reactivity, and temperature. Then, the effects of changes in kinetic parameters including the Doppler coefficient, prompt neutron lifetime, and delayed neutron fractions on simultaneous reactivity insertion and beam tube flooding accidents were analyzed. Results show that the power peak values are significantly sensitive to the Doppler coefficient of the system in coupled accidents. The material testing reactor-type system under such a coupled accident is not very sensitive to changes in the prompt neutron life time; the core under such a coupled transient is not very sensitive to changes in the effective delayed neutron fraction.

• PNF and Movement
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• v.12 no.1
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• pp.45-50
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• 2014

Purpose: Deficits in upper-extremity function in individuals with tetraplegia are primarily due to the loss of motor pathways. The purpose of this case report is to describe the effect of closed kinetic chain exercise using PNF on hand function and ADL of patient with incomplete spinal cord injure. Methods: Patient was a 53-year-old man with C4 tetraplegia and hand and upper extremity impairment who participated in this training intervention for 10 weeks. Results: Patient demonstrated improvements in upper extremity strength, hand function and performance of ADL. Outcome measures(ASIA motor scale, Hand power, Jebsen-Taylor Hand Function test, SCIM) were measured before and after the training program. Conclusion: The results of this case suggests that an closed kinetic chain exercise program in incomplete spinal cord injury patient may induce Hand function and ADL.

• Bulletin of the Korean Chemical Society
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• v.30 no.12
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• pp.2909-2912
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• 2009

The amines studied in this study are less reactive toward ethyl propiolate (3) in MeCN than in H$_2$O although they are 7 to 9 pK$_a$ units more basic in the aprotic solvent. The reactivity of morpholine and deuterated morpholine toward 3 is found to be identical, indicating that proton transfer occurs after rate-determining step (RDS). The fact that kinetic isotope effect is absent excludes a stepwise mechanism in which proton transfer occurs in RDS as well as a concerted mechanism in which nucleophilic attack and proton transfer occur concertedly through a 4-membered cyclic transition state (TS). Thus, the reactions have been concluded to proceed through a stepwise mechanism in which proton transfer occurs after RDS. Brønsted-type plots are linear with small ${\beta}_{nuc}$ values, i.e., ${\beta}_{nuc}$ = 0.29 in H$_2$O and ${\beta}_{nuc}$ = 0.51 in MeCN, indicating that bond formation is not advanced significantly in RDS. The small ${\beta}_{nuc}$ value also supports the conclusion drawn from the study of kinetic isotope effect.

• Journal of Microbiology and Biotechnology
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• v.13 no.3
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• pp.332-337
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• 2003

Enzyme kinetics data play a vital role in the design of reactors and control of processes. In the present study, kinetic studies on pectinases were carried out. Partially purified polymethylgalacturonase (PMG) and polygalacturonase (PG) were the two pectinases studied. The plot of initial rate vs. initial substrate concentration did not follow the conventional Michaelis-Menten kinetics, but substrate inhibition was observed. For PMG, maximum rate was attained at an initial pectin concentration of 3 g/l, whereas maximum rate was attained when the initial substrate concentration of 2.5 g/l of polygalacturonic acid for PG I and PG II. The kinetic data were fitted to five different kinetic models to explain the substrate inhibition effect. Among the five models tested, the combined mechanism of protective diffusion limitation of both high and inhibitory substrate concentrations (semi-empirical model) explained the inhibition data with 96-99% confidence interval.

• Transactions of the Korean Society of Automotive Engineers
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• v.1 no.3
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• pp.22-33
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• 1993

A theoretical analysis of predicting the detailed motion of a piston-crank mechanism within piston-guide clearance is presented, and the analysis is applied to the piston motion in a gasoline engine. A piston movement program is developed to calculate the piston attitude relative to the bore, the piston to bore impact velocity and kinetic energy loss and the net transverse force acting on the piston. This paper presents the formulation of a set of differential equations governing the transverse and rotational motion of a piston. These equations of motion were solved by well established Runge-Kutta method. As a result of this study, it is possible to predict the effects of piston geometry and piston pin offset on a piston motion and kinetic energy loss.

• Proceedings of the Korean Powder Metallurgy Institute Conference
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• 2006.09a
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• pp.242-243
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• 2006

NiTiZrSiSn bulk metallic glass powder was produced using inert gas atomization and then was sprayed onto a SS 41 mild steel substrate using the kinetic spraying process. Through this study, the effects of thermal energy of in-flight particle and crystallization degree by powder preheating temperature were evaluated. The deformation behavior of bulk metallic glass is very interesting and it is largely dependent on the temperature. The crystalline phase formation at impact interface was dependent on the in-flight particle temperature. In addition, variations in the impact behavior need to be considered at high strain rate and in-flight particle temperature.