• The Journal of Korean Physical Therapy
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• 제11권1호
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• pp.167-177
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• 1999

Biomechanics is an important scientific foundation of physical therapy and is used to relate kinematics, kinetics, statics and dynamics for comprehencing human movement. The knee is well studied for demonstrating biomechanical analyses of joint because of its simplicity. The purposes of this study were 1)to provide categories and concepts of biomechanics, 2) to apply these concepts to knee movement involving daily living and gait, and 3) to review current and preceeding researches about biomechanics of knee. Thus, physical therapiestes in clinic may be helped understand of movement which includes considerations of description and production related force, moment and power.

• 대한화학회지
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• 제16권5호
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• pp.284-289
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• 1972

벤질브로마이드와 여러가지 m-또는 p-핵치환 지오벤즈아미드류와의 반응속도를 전기전도도법으로 측정하였다. 이들 반응에서 전자흡인치환기는 반응속도를 촉진하였고 한편 전자공여치환기는 반응속도를 억제하였다. 이 사실에 부합하는 반응 메카니즘을 고찰하였다. 추가하여 이들 반응에 있어서의 활성화에너지와 활성화엔트로피를 산출하였다.

• Archives of Pharmacal Research
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• 제17권5호
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• pp.378-380
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• 1994

The hydrolysis of metampicillin to ampicillin was investigated using high perofrmance liquid chromatography. We developed the simultaneous determination of metampicillin and ampicilin using a Zorbox CN column and 5% acetonitrile and 8% methanol in 0.02 M phosphate buffer (pH 7.0) as mobile phase. Matampicillin was hdyrolyzed to ampicillin with half life of 41.5 min at physiological pH and temperature. In acdic pH, metampicillin was rapidly hydrolyzed to ampicillin within a chromatogrphic separation.

• 환경위생공학
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• 제15권4호
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• pp.44-51
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• 2000

The reactivity of a range of volatile organic compounds with differing functional groups observed over 0.5% $Pt/{\gamma}-Al_2O_3$ catalyst. In general, the reactivity pattern observed was alcohols > aromatics > ketones > cycloalkane > alkanes. The deep conversion was increased as reaction temperature was increased. A correlation was found between the reactivity of the individual and the strength of the weakest C-Hbond in structure. The conversion of volatile organic compounds increases in order methanol > benzene > cyclohexane > MEK > n-hexane. That is the effect of differences in total dissociation energy. An apparent zeroth-order kinetics with respect to inlet concentration have been observed. A simple multicomponent model based on two-stage redox model made reasonably good predictions of conversion over the range of parameters studied. thus, the catalytic process was suggested as the new VOCs control technology.

• 펄프종이기술
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• 제39권5호
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• pp.7-11
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• 2007

Kraft pulping of Trema orientalis (Nalita) was studied in order to find kinetic data for delignification. Pulping runs were carried out in the temperature range of $160-180\;^{\circ}C$ under constant and well-defined conditions. The delignification was found to be first order with respect to residual lignin and was chemically controlled. The rate of delignification reaction was increased 1.11-1.23 for $10\;^{\circ}C$ temperature increase in the range of $160-180\;^{\circ}C$ range. A mean value of 93% of lignin was removed at the transition between bulk and residual delignification. The influence of cooking temperature on the rate constant was expressed by an Arrhenius-type equation. The obtained activation energy of the delignification reaction was 6,164 cal/mol. The transition point between bulk and residual phase was shifted to lower lignin and carbohydrate yield with the increase of temperature.

• Environmental Sciences Bulletin of The Korean Environmental Sciences Society
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• 제10권S_4호
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• pp.165-172
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• 2001

We investigated the optimal experimental conditions and reaction kinetics for the decompositions of PCE, TCE, naphthalene, and chloroform using conventional Fenton oxidation process. Additionally, the influence of pH on the decompositions of PCE was also evaluated. The results indicated that the optimal pH value was around 3. The dosage of Fenton's reagent and the molar ratio of hydrogen peroxide to ferrous ion for an approximately complete decomposition was found to depend on the properties of the organic compound. Due to their unsaturated structures, the results show that PCE, TCE, and naphthalene could be all effectively decomposed by Fenton's reagent oxidation. Their unsaturated structures could be mostly destoyed within first 1-2 minutes at a low dosage with an certain molar ratio of hydrogen peroxide to ferrous ion. However the saturated compound such as chloroform was more difficult to decompose even with a relatively high dosage of Fenton's reagent.

• 한국환경과학회지
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• 제9권1호
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• pp.75-80
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• 2000

Kinetic data for the acid phase anaerobic digestion were presented in this study and the constants were determined with acid production rate and gas production rate. Process models based on continuous culture theory were used to describe the characteristics of the acid forming microorganisms and to enable further development toward utilization of the process in a more rational manner. Acid phase digestion can be separated with appropriate manipulation of hydraulic retention time in anaerobic digestion. Kinetic analysis of data from the various hydraulic retention times using a phase specific model obtained form the acid phase indicated maximum specific growth rate of 0.40/h, saturation constant of 2,000mgCOD.$\ell$, yield coefficient of 0.35 mgVSS/msCOD utilized and decay constant of 0.04/h for the acid production rate. Similar analysis of data for the gas production rate indicated maximum specific growth rate of 0.003/h, saturation constant of 2,200mgCOD/$\ell$, yield coefficient of 0.035 mgVSS/mgCOD utilized and decay constant of 0.06/h.

• 대한전기학회:학술대회논문집
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• 대한전기학회 1997년도 추계학술대회 논문집 학회본부
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• pp.345-347
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• 1997

The thermal decomposition kinetics of epoxy resin system as an electrical insulator for high voltage was investigated by using thermogravimetric analysis and Horowitz & Metzger equation. Epoxy resin system was degraded by one stage. The thermal decomposition activation energies of epoxy resin systems were all about 380 kJ/mol at the GN contents of 0 and 5 phr, and it abruptly decreased at 10 phr.

• Journal of Microbiology and Biotechnology
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• 제13권2호
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• pp.309-312
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• 2003

A bacterial strain NB01, isolated from wastewater, was found to utilize nitrobenzene (NB) as the sole source of nitrogen, carbon, and energy. The strain was classified as a member of a high G+C Gram-positive group and identified as Mycobacterium chelonae based on an analysis of its 16S rRNA gene sequence. The strain grew on NB with a concomitant release of about 63% of the total available nitrogen as ammonia, suggesting a reductive degradation mechanism. The optimal pH and temperature for degradation were PH 7.0-8.0 and $30^{\circ}C$, respectively. The cell growth was retarded at NB concentrations above 1.8 mM. The degradation of NB followed Michaelis-Menten kinetics within the tolerance range, and the $K_m$ and maximum specific removal rate for NB were 0.33 mM and $11.04\;h^{-1}$, respectively.

• 대한기계학회논문집B
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• 제28권12호
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• pp.1494-1500
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• 2004

A zero-dimensional direct simulation Monte Carlo(DSMC) model is developed for simulating diatomic gas including vibrational kinetics. The method is applied to the simulation of two systems: vibrational relaxation of a simple harmonic oscillator and translational-rotational-vibrational energy exchange process under heating and cooling. In the present DSMC method, the variable hard sphere molecular model and no time counter technique are used to simulate the molecular collision kinetics. For simulation of diatomic gas flows, the Borgnakke-Larsen phenomenological model is adopted to redistribute the translational and internal energies.