• Journal of the Korean Magnetics Society
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• v.15 no.2
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• pp.85-91
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• 2005

Effect of different cations to the formation of iron oxyhydroxide was studied using $M\ddot{o}ssbauer$ spectroscopy, X-ray diffraction (XRD) and BET. Redox Potential and pH were measured for the determination of the internal reaction rate, as well. The phases of iron oxyhydroxide could not be the same with each other, due to the presence of different cations in solution. Although the oxyhydroxide compound was composed of the same phases, the fraction of each phase was different from each other. The internal reaction rate was varied by the substitution of cation. It could be a cause of the different phase and particle size of oxyhydroxide compound.

• Journal of Haehwa Medicine
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• v.15 no.2
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• pp.263-272
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• 2006

Purpose Brain vessles have autoregulation function, so even when perfusion pressure drops, cerebral blood flow remain stable by vasodilation. Latest research on this reserve of cerebral vessels is being done using TCD, which measures the reserve of the vessels. We did a research comparing cerebral vessel and peripheral vessel reserve between Taeumin, who are more likely to suffer CVA, and the normal. We observed blood flow of Internal carotid artery siphon and radial indicis artery of the two group with TCD. Method We picked 20 people out of patients diagnosed as cerebral infarction at Cheon-An Oriental hospital of Daejeon University. They were diagnosed as Taeumin with QSCCII questionnaire and constitutional differentiation. Using TCD, we measured highest blood flow rate, mean blood flow and asymmetric counting blood flow of Internal carotid artery siphon and radial indicis artery at rest. And then we measured again after stimulating cerebral vessels, by triggering hypercapnia by self apnea and peripheral vessels by palm heating. Result At rest, mean blood flow rate of Internal carotid artery siphon showed significant decrease compared to control group. Blood flow rate of Internal carotid artery siphon after hypercapnia showed significant decline in highest blood flow rate and mean blood flow compared to control group. Cerebral vessel reaction after the hypercapnia induction showed great change in experiment group than the control group. Peripheral vessel reaction after palm heating showed significant decline in experiment group compared to control group. Conclusion In conclusion, measuring the alteration of blood flow used in diagnosing cerebral infarction, is more sensitive when vessel stimulation is done. Non-invasive TCD is effective especially in case of Taeumin who are more likely to suffer vascular disorder than others.

• Journal of the Korean Society of Combustion
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• v.21 no.4
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• pp.23-29
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• 2016

Reactivity of gasification defined by bouardard reaction is critical parameter in efficiency of the gasifier. In this study, char reactivity of the gasification was derived from the experiments using the intrinsic reaction kinetics model. Pressurized wire mesh heating reactor (PWMR) can produce high temperature and high pressure conditions up to 50 atm and 1750 K, respectively and PWMR was designed to evaluate the intrinsic reaction kinetics of $CO_2$ gasification. In this study, Kideco and KCH (sub-bituminous Indonesian coal) were pulverized and converted into char. Experiments used the PWMR were conducted and the conditions of the temperature and pressure were 1373~1673 K, 1~40 atm. To distinguish the pressure effect from high pressurized condition, internal and external effectiveness factors were considered. Finally, the intrinsic kinetics of the Kideco and KCH coal char were derived from $n^{th}$ order reaction rate equations.

• Korean Chemical Engineering Research
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• v.52 no.1
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• pp.133-140
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• 2014

The experiment was designed to compare the char combustion kinetics of pulverized Indonesia coals commonly utilized in Korea power plants. The reaction rate of coal char has been formulated using the external and internal effectiveness factors to describe the diffusion effect quantitatively. The Random Pore Model (RPM) was used for applying internal specific surface area as a function of carbon conversion ratio. Reaction rate was obtained from reaction time using the Wire Heating Reactor (WHR) which can heat and measure the char particle temperature at the same time. BET and TGA were used to obtain physical properties such as internal specific surface area and structural parameter. Three kinds of Indonesia Sub-bituminous coals "BARAMULTI, ENERGYMAN, AGM" were used in order to derive the activation energy and pre-exponential factor. The results of this study showed that the effect of internal diffusion than that of external diffusion is the dominant as comparison of kinetics was reflected in external and internal effectiveness factors. For three kinds of coal char, finally, activation energy of intrinsic kinetics indicates 110~118 kJ/mol.

• Bulletin of the Korean Chemical Society
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• v.20 no.10
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• pp.1181-1185
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• 1999

The reaction of FeC5H5+ ion with ferrocene molecule is investigated using FT-ICR mass spectrometry. FeC5H5+ ions are generated by dissociative ionization of ferrocenes using an electron beam. The reaction gives rise to the formation of the adduct ion, Fe2(C5H5)3+, in competition with charge transfer reaction leading to the formation of ferrocene molecular ion, Fe(C5H5)2+·. The branching ratio of the adduct ion increases as the internal energy of the reactant ion decreases and correspondingly the branching ratio for the charge transfer reaction product decreases. The observed rate of the addition reaction channel is slower than that of the charge transfer reaction. The observation of the stable adduct ions in the low-pressure ICR cell is attributed to the radiative cooling of the activated ion-molecule complex. The mechanism of the reaction is presented to account for the observed experimental results.

• Korean Journal of Materials Research
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• v.12 no.10
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• pp.796-802
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• 2002

Effect of nine different cations to the formation of iron oxyhydroxide was studied using Mossbauer spectroscopy, XRD and BET. The Redox Potential and pH were measured for the determination of the internal reaction rate, as well. The phases of iron oxyhydroxide could not be the same with each other, due to the present of different cations in solution. Although the oxyhydroxide compound were composed of the same phases, the fraction of each phase was different from each other. The internal reaction rate was varied by the substitution of cation. It could be a cause of the different phase and particle size of oxyhydroxide compound.

• YAKHAK HOEJI
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• v.19 no.2
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• pp.101-110
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• 1975

p-Chloronitrobenzene(substrate) and p-nitrophenetole (product) were quantitatively analyzed to know the degree of extent of reaction in the process of time. The calibration curve was prepared by the internal satndard method in gaschromatography. 2,6-Dimethyl-naphthalene was used as internal standard. The rate constant(k), the reaction velocity in various concentrations of NaOH altered, and the formation of byproducts(azo-compound and p-nitrophenol) with the amounts of MnO$_{2}$ and NaOH altered, were studied. From the results of these of MnO$_{2}$ and NaOH altered, were studied. From the results of these experiments, this reaction was second order and the rate constant was k=10.3 $\times$ 10$^{-3}$ mole$^{-21$. When p-chloronitrobenaene 1 pt. NaOH 0.56pts. MnO$_{2}$ 0.5pts. and ethanol 25 pts-were reacted about 10 hours, p-nitrophenetole was nearly quantitatively obtained without byproducts.

• Journal of Korean Society on Water Environment
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• v.23 no.5
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• pp.761-765
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• 2007

The study were conducted in order to investigate the effect of operating parameters including the internal recycle (nitrification return) rates, hydraulic retention times (HRTs) and temperature when using a cilium media method. The first experiment was for evaluating the effect of HRT (12 hr, 10 hr, 8 hr, 6 hr, 4 hr). The second experiment was for analyzing effect of internal recycle rate (100%, 200%, 300%, 400%). As a result of the first experiment, BOD was removed to 97~98% for 6~8 hr HRT. Effluent water quality was not significantly influenced with HRT within that range. However the nitrogen removal was sensitive to HRT. T-P removal efficiency was invariable at various HRTs. The average BOD removal efficiency was about 97% in spite of change of internal recycle rate while T-N removal efficiency was increased at the internal recycle rate of 100~200%, but invariable at the internal recycle rate of 200~300%.

• Ecology and Resilient Infrastructure
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• v.10 no.4
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• pp.125-134
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• 2023

In order to develop a backtracking technique for turbidity measurement data without discriminatory characteristics, three turbidity backtracking techniques for predicting inflow turbidity of a stream were compared using real-time turbidity data measured at automatic water quality measurement points located upstream and downstream of the stream and the Py_STPS model. Three turbidity backtracking techniques were applied: 1) simple preservation method of turbidity load considering flow time, 2) a method of using the flow rate at the upstream boundary considering the flow time as the flow rate at the downstream boundary, 3) method of introducing internal reaction rate to reflect the behavior characteristics of turbidity-causing substances. As a result of applying the three backtracking models, it was confirmed that the backtracking technique that introduced the internal reaction rate had the best results.

• Gut and Liver
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• v.12 no.6
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• pp.648-654
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• 2018

Background/Aims: Dual priming oligonucleotide-based multiplex polymerase chain reaction (DPO-based PCR) can detect the presence of clarithromycin resistance without culture. The aim of this study was to investigate the cost-effectiveness of DPO-based PCR for Helicobacter pylori eradication. Methods: From 2015 to 2016, medical records of patients who received H. pylori eradication therapy were analyzed. Patients were divided into two groups: tailored group patients who were treated based on DPO-based PCR and empirical group patients. Eradication rate and medical cost, including diagnostic tests, eradication regimens, and $^{13}C$-urea breath tests, were compared between the two groups. Cost for one successful eradication was calculated in each group. The expected cost of eradication for empirical treatment was investigated by varying the treatment duration and eradication rate. Results: A total of 527 patients were analyzed (tailored group 208, empirical group 319). The eradication success rate of the first-line therapy was higher in the tailored group compared to that in the empirical group (91.8% vs 72.1%, p<0.01). The total medical cost for each group was $114.8{\pm}14.1U.S.$ dollars (USD) and $85.8{\pm}24.4USD$, respectively (p<0.01). The total medical costs for each ultimately successful eradication in the tailored group and in the empirical group were 120.0 USD and 92.4 USD, respectively. The economic modeling expected cost of a successful eradication after a 7- or 14-day empirical treatment was 93.8 to 111.4 USD and 126.3 to 149.9 USD, respectively. Conclusions: Based on economic modeling, the cost for a successful eradication using DPO-based PCR would be similar or superior to the expected cost of a successful eradication with a 14-day empirical treatment when the first-line eradication rate is ${\leq}80%$.