• Nuclear Engineering and Technology
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• v.52 no.12
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• pp.2717-2724
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• 2020

Silicon, especially silicon in the form of SiO₂, is a major component of rocks. Final spent fuel storages, which are being designed, are located in suitable rock formations in the Earth's crust. Reduction of the uncertainty of silicon neutron scattering and capture is needed; improved silicon evaluations have been recently produced by the ORNL/IAEA collaboration within the INDEN project. This paper deals with the nuclear data validation of that evaluation performed at the LR-0 reactor by means of critical experiments and measurement of reaction rates. Large amounts of silicon were used both as pure crystalline silicon and SiO₂ sand. The critical moderator level was measured for various core configurations. Reaction rates were determined in the largest core configuration. Simulations of the experimental setup were performed using the MCNP6.2 code. The obtained results show the improvement in silicon cross-sections in the INDEN evaluations compared to existing evaluations in major libraries. The new Thermal Scattering Law for SiO₂ published in ENDF/B-VIII.0 additionally reduces the discrepancy between calculation and experiments. However, an unphysical peak is visible in the neutron spectrum in SiO₂ obtained by calculation with the new Thermal Scattering Law.

• Journal of Microbiology and Biotechnology
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• v.33 no.1
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• pp.123-126
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• 2023

The prevalence of candidiasis, a contagious disease with high morbidity and mortality, has sharply increased globally over the last two decades. Candida albicans can cause serious infections in patients with weak immunity and in recipients of prolonged antibiotic treatment. Consequently, rapid and accurate identification of species can play an important role in the treatment of candidiasis. Here, we investigated the positive rate and infection trend of C. albicans according to age, specimen type, and sex using multiplex real-time polymerase chain reaction-based testing of samples collected for the diagnosis of sexually transmitted diseases in Korea between 2018 and 2020. When the type of specimen collected was a swab, the positive rate of C. albicans was higher among younger women, and tended to decrease with age. Analysis of swab samples revealed higher positive rates than urinalysis. The reduction trend in positive rates by age was comparable between the overall samples and urine specimens. Among male patients, the positive rate did not differ substantially across the various types of specimens collected. Previous studies have shown a higher prevalence of non-albicans Candida species than C. albicans in clinical specimens, and exclusion of the former from our analysis may be a limitation of this study. However, our findings contribute significantly to the literature because globally, there is a paucity of epidemiological studies using molecular techniques to detect C. albicans in sexually transmitted disease test samples.

• Parasites, Hosts and Diseases
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• v.37 no.2
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• pp.109-115
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• 1999

The present study observed the variation of antigenicity of Pneumocystis carinii and serum IgG antibody reastion to the antigens from different localtities in Korea. Antigens of rat P,carinii and sera of inhabitants were collected at Chunchon, Chungju, Kwangju and Seoul during 1995-1996. Enzyme-Linked Immunosorbent Assay and immunoblot were used for immune reaction. Absorbance of 1,294 human sera ranged between 0.01and 0.93. Sera from Chunchon showed higher absorbances than those from other areas. Immunoblotting revealed IgG antibody reactions to 116,100, and 45-55 kDa antigenic bands of rat P.carinii, but the frequencies of positive reaction to individual bands were variable by localities. Total 62.6% reacted to 100kDa band and 32.0% to 45-55 kDa bands. For the reaction to 116kda, the reaction rate was 60.0% of the sera showed the reaction to 116kda band while 37.7% reacted to 100kda, the reaction rate was 60.0% to 82.6% by localities. It is found that the reaction rates of the human sera to rat P.carinii antigen are variable according to the localities. Also, the high molecular antigen of 116kDa of rat P.carinii is the most frequent antigenic band reaction to human sera.

• Korean Chemical Engineering Research
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• v.47 no.5
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• pp.639-645
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• 2009

In this study, alkanolamine was used to achieve high absorption rates for $CO_2$ as suggested at several literatures. The absorption rates of aqueous AMP and MEA solutions with $CO_2$, $SO_2$, $NO_2$ were measured using a stirredcell reactor. The reaction rate constants were determined from the measured absorption rates. The performances were evaluated under various operating conditions. As a result, the reactions with $SO_2$, $NO_2$ into aqueous AMP and MEA solutions were classified as an instantaneous reaction respectively. The absorption rates increased with increase of the reaction temperature and the concentration of absorbents. The simultaneous absorption rate of $CO_2/SO_2/NO_2$ into 3, 5, 10 wt.% MEA at various pressure of $CO_2/SO_2/NO_2$, was more increased 14~20% than AMP solution. We investigated the effect of $SO_2$ and $NO_2$ on the simultaneous absorption of $CO_2/SO_2/NO_2$ from a flue gas. The performances were evaluated under various operating conditions in order to investigate the absorption characteristic.

• Korean Journal of Veterinary Research
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• v.16 no.2
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• pp.151-158
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• 1976

The tuberculin test have been widely utilized to diagnose tuberculosis of the dairy cattle. It was reported that approximately 70% of the dairy cattle with positive tuberculin reaction in Korea had been non-pathogenic lesion. So the studies on the specific method to diagnose tuberculosis of them is really need in Korea. Therefore this study investigated upon the diagnostic method for cattle tuberculosis in the aspect of cellular-immunology. The results obtained in this investigation are summarized as follows: 1. All the tuberculin tests to the swine inoculated with BCG.(B group), Mycobacterium avium (A group) and Mycobacterium smegmatis (S group), respectively, were represented high positive reaction and were no differences in the species of inoculated bacteria. 2. In the migration inhibition test using Iymphocyte in circulating blood of the swine inoculated with three species of acid-fast bacteria respectively, the test to A group was represented slight positive for migration in the presence of $15{\mu}g/ml$-PPD and the other reaction were clear and total positive for migration inhibition in the presence of $25{\mu}g/ml$-PPD or more, and the test to B group was the same results as to A group approximately. The test to S group was represented slight positive for migration inhibition in the presence of $15{\mu}g/ml$-PPD, but the results were the same in the presence of $25{\mu}g/ml$-PPD and $35{\mu}g/ml$-PPD. These results showed that there were remarkable differences between group A, B and group S in the presence of $25{\mu}g/ml$-PPD and $35{\mu}g/ml$-PPD. 3. The transformation rates of lymphocyte in PPD treated tissue culture had no significance without any relation between PPD treatment and non-treatment but A group and B group showed significance. And A group and B group showed high significance in comparison with N group and S group in the LSD examination. 4. The infection rated in lymphocyte of BCG inoculated after 3 days tissue culturing were represented those of high infection but its cellular degeneration rates almost did not change. The infection rates in bacilli in N group and S group were low but after 3 days inoculation it shewed higher cellular degeneration.

• Proceedings of the KIEE Conference
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• 1992.07b
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• pp.662-665
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• 1992

Effects of reactant gas flow rates and starvation on phosphoric acid fuel cell performance were studied. As the reactant gas flow rates increased, the cell performance increased and then the cell maintained constant performance. The optimum flow rates of hydrogen, oxygen and air under galvanostatic condition of 150 mA/$\textrm{cm}^2$ are found to be 3cc/min${\cdot}\textrm{cm}^2$, 4cc/min${\cdot}\textrm{cm}^2$, and 15cc/min${\cdot}\textrm{cm}^2$, respectively. Hydrogen and oxygen starvation resulted in voltage loss of about 5mV and 0-2mV, respectively. The voltage loss was independent of starvation time. These results were discussed from the point of view of electrochemical reaction of the cell.

• Journal of the Korean Vacuum Society
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• v.8 no.4B
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• pp.565-571
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• 1999

In this study, high-density plasma etching characteristics of ITO(indium tin oxide) films used for transparent electrode in dispaly devices were investigated. Plasma diagnostic and surface analysis tools were used to understand etch reaction mechanism. The etch rate of ITO was increased by the increase of reactive radicals such as H and $CH_3$ with the addition of moderate amount of $CH_4$ to Ar. However, the addition of excess amount of $CH_4$ decreased possibly due to the increased polymer formation on the ITO surface being etched. The increase of source power and bias boltage increased ITO etch rates but it decreased selectivities over under-layers $(SiO_2, Si_3N_4)$. The increase of working pressure up to 20mTorr also increased ITO etch rates, however the further increased of the pressure decreased ITO etch rates. From the analysis of XPS, a peak related to the polymer of hydrocarbon was observed on the etched ITO surface especially for high $CH_4$ conditions and it appears to affect ITO etch rates.

• Journal of Environmental Health Sciences
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• v.22 no.3
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• pp.98-102
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• 1996

This study investigated performance of the phenol degradation and reaction characteristics according to variation of phenol volumetric loading rates and dilution rates in suspension and PACT reactors using Pseudomonas sp. B3. 1. Removal efficiencies of the PAC unit indicated about 100 % with phenol volumetric loading rates from 0.4 phenol $kg/ma^3\cdot d$ to 1.2 phenol $kg/m^3\cdot d$, however, which of the suspension reactor showed about 100% with from 0.2 phenol $kg/m^3\cdot d$ to 0.75 phenol $kg/ma^3\cdot day$. 2. The cell density slightly was decreased from 298.2 mg/l to 272 mg/l, when dilution rate for suspension was reactor increased from 0.4 to 1.41 1/d, and also the cell density suddenly was decreased to 145.5 mg/l and was washed out at the dilution rate higher than 1.60 1/d. But the cell density for the PAC unit was linearly decreased with dilution rate of from 0.8 to 3.0 1/d, and showed 220.75 mg/l at maximum dilution rate. 3. The phenol utilization rate was increased from 0.008 to 0.031 phenol g/l$\cdot$h, when dilution rate for suspension reactor was increased from 0.4 to 1.5 1/d, however, the rate for the PAC unit was linearly increased from 0.017 to 0.061 phenol g/l$\cdot$h as variation changes from 0.017 to 0.061 phenol g/l$\cdot$h dilution rate.

• 한국연소학회:학술대회논문집
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• 2002.11a
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• pp.1-9
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• 2002

Simultaneous PIV and OH PLIF measurements are used for shear strain rates and flame locations, respectively. It is believed that the shear strain rates represent flow characteristics such as turbulence intensity and the OH intensity indicates the flame characteristics such as burning velocities. However, these are still lack of geometric information, which may be very important to flame quenching Hence, fractal dimensions 'Df) of the OH images are adopted as an additional information. Finally, the flame structure diagram proposed in this research has three parameters, which consist of strain rates, OH intensities and fractal dimensions. The results show that this diagram classifies turbulent premixed flames more effectively based on flame structures. The regime of weak turbulence is limited to narrow strain ranges and has the fractal dimension of about 2 In the regime of moderate turbulence, OH intensities increase as strain rates increase and the values of fractal dimensions are 1.8 Df 1.95. The regimes of thickened reaction and flame extinction (quenching) show bell-shaped and their values of fractal dimensions are 1.5 Df 1.7 and 0.9 Df 0.6, respectively.

• Journal of the Semiconductor & Display Technology
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• v.18 no.1
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• pp.65-69
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• 2019

The cure properties of ethoxysilyl diglycidyl isocyanurate(Ethoxysilyl-DGIC) and ethylsilyl diglycidyl isocyanurate (Ethylsilyl-DGIC) epoxy resin systems with a phenol novolac hardener were investigated for anticipating fan out-wafer level package(FO-WLP) applications, comparing with ethoxysilyl diglycidyl ether of bisphenol-A(Ethoxysilyl-DGEBA) epoxy resin systems. The cure kinetics of these systems were analyzed by differential scanning calorimetry with an isothermal approach, and the kinetic parameters of all systems were reported in generalized kinetic equations with diffusion effects. The isocyanurate type epoxy resin systems represented the higher cure conversion rates comparing with bisphenol-A type epoxy resin systems. The Ethoxysilyl-DGIC epoxy resin system showed the highest cure conversion rates than Ethylsilyl-DGIC and Ethoxysilyl-DGEBA epoxy resin systems. It can be figured out by kinetic parameter analysis that the highest conversion rates of Ethoxysilyl-DGIC epoxy resin system are caused by higher collision frequency factor. However, the cure conversion rate increases of the Ethylsilyl-DGEBA comparing with Ethoxysilyl-DGEBA are due to the lower activation energy of Ethylsilyl-DGIC. These higher cure conversion rates in the isocyanurate type epoxy resin systems could be explained by the improvements of reaction molecule movements according to the compact structure of isocyanurate epoxy resin.