• Food Science and Preservation
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• v.6 no.2
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• pp.153-160
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• 1999

This study was carried out to investigate the production of C$_2$H$_4$ and CO$_2$, and the change of flesh firmness and peel color in 'Fuji' apples during CA storage. ACC oxidase activity was more inhibited by the low O$_2$ concentration, and the low level of internal C$_2$H$_4$ in apples was maintained under the low O$_2$ conditions during 8 months storage. Especially, the level of internal C$_2$H$_4$ in apples was maintained below 1 ppm during storage under 1% O$_2$+1% CO$_2$ at 0$^{\circ}C$, and not much changed for 7 days in air at 20$^{\circ}C$ after storage. The influence of CO$_2$ on the C$_2$H$_4$ production was dependent on the O$_2$ concentration. Increasing of CO$_2$ concentration with 3% O$_2$ decreased the C$_2$H$_4$ Production during storage, but that with 1% O$_2$increased. Internal C$_2$H$_4$ concentration and the rate of CO$_2$ evolution in apples showed the close correlation. Internal CO$_2$ concentration of apples was positively related to the rate of CO$_2$ evolution and maintained the lower level in 1% O$_2$+1% CO$_2$ than the other conditions during storage but nu different in the increment after storage. The relationship between C$_2$H$_4$ and CO$_2$ production was exhibited in CA and the short-term air stored apples, but not in the long-term air stored apples. Loss of flesh firmness and green color in apples was more less in storage condition retarded effectively the production of C$_2$H$_4$ and CO$_2$.

• Proceedings of the Korean Society of Soil and Groundwater Environment Conference
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• 2002.04a
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• pp.199-202
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• 2002

Many methods have been developed for the remediation of contaminated soil and groundwater. Among those technologies, in-situ bioremediation is most likely to be cost-effective method for petroleum hydrocarbon contamination. But the in-situ bioremediation can require more time to remediate hydrocarbon-contaminated soil and groundwater than other methods. Therefore we intended to save time of in-situ bioremediation using a biological additive to activate indigenous microbes in soil. The additive, 'Inipol EAP 22' stimulates the growth of specific flora, significantly accelerating the speed at which hydrocarbons are biodegraded. And it hans been tested in accordance with protocol approved by the USEPA and is registered on the National Contingency Plan Product Schedule List. In the experiment, three soil samples contaminated with fuel oil were prepared in the same concentration. Inipol EAP 22 was not added to one sample and was added to the other two samples with 5% and 10% of hydrocarbon by weight respectively. And $CO_2$gas derived from bacterial respiration was analyzed in each samples for 15 days. As a result, 145% and 153% of $CO_2$ evolution (microbial respiration) against the sample without 'Inipol EAP 22' occurred in samples with 'Inipol EAP 22' addition of 5% and 10%, respectively

• Journal of the Korean Magnetics Society
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• v.11 no.2
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• pp.63-71
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• 2001

The effects of an Ag seed layer on the magnetic properties and the microstructural evolution of SmCo/Cr thin films deposited on glass substrates were investigated. Coercivity of the films is 2.0 kOe when the thickness of Ag seed layer was 1nm thick, but it increased to 2.7 kOe when the Ag seed layer thickness is 3 nm. The increase of coercivity for film with 3 nm-thick Ag is due to roughness of Cr and grain size of Cr by the Ag microbumps. Ar partial pressure influenced on the formation of Ag microbumps, for example, they were formed at 5 mTorr when Ag thickness was 1 nm. The mechanism of magnetization reversal of the SmCo films changed from domain wall motion to domain rotation as the Ag inserted. This was thought to be due to inhibition of domain wall motion by the reduction of Cr grain size and the increase of roughness.

• Microbiology and Biotechnology Letters
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• v.9 no.3
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• pp.123-128
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• 1981

The effects of the crude saponin extracted from ginseng leaves on carbon dioxide evolution, alcohol fermentation, and cell production by Saccharomyces cerevisiae were investigated. The results were summarized as follows : 1) In the process of fermentation, $CO_2$ evolution by yeast was faster in the order of 3%, 1.5%, 0.7%, 5%, 7%, 0.3% than in control in concentration of the crude saponin extracts. 2) In the course of fermentation, the content of alcohol increased in the order of 0%, 0.3%, 7%, 1.5%, 3%, 5%. Among all these concentration, the production of alcohol was remarkably much in 5% and 3%. 3) In the process of fermentation, pH in the low content (0-0.7%) of the crude saponin extracts was gradually decreased as tine goes by and in the high content (1.5-7%) dropped suddenly between 24 hrs. and 48 hrs., and after 48 hrs., increased. 4) Dried yeast cell weight increased more in all the above concentration than control (0%) and among these it increased visibly in 3%.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.6 no.3
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• pp.273-277
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• 2005

We prepared $0.25\~l.5um$ poly silicon gate array test group with $SiO_2$ spacers in order to employ NiCo composite salicide process from 15nm Ni/15nm Co/poly structure. We investigate the residual metal shape evolution by varying the rapid thermal silicide anneal temperature from $700^{\circ}C\;to\;1100^{\circ}C$. We observed the residual metals agglomerated into maze type and line type on $SiO_2$ field and silicide gate, respectively as temperature increased. We propose that lower silicide temperature would be favorable in newly proposed NiCo salicide in order to lessen the agglomeration causing the leakage and scum formation.

• The Bulletin of The Korean Astronomical Society
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• v.43 no.2
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• pp.45.2-45.2
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• 2018

Twisted magnetic flux tubes (also called magnetic flux ropes) are believed to play a crucial role in solar eruptive phenomena. The evolution of a single flux rope with or without the influence of an overlying field of a simple geometry has been extensively studied and its physics is rather well understood. Observations show that interacting flux tubes are often involved in solar eruptions. It was Lau and Finn (1996) who intensively studied the interaction between two flux ropes, whose footpoints are anchored in two parallel planes. In this too simplified setting, the curvature of the flux rope axial fields is totally ignored. In our study, the footpoints of flux ropes are placed in a single plane containing a polarity inversion line as in the real solar active region. Our simulation study is performed for four cases: (1) co-axial field and co-axial current (co-helicity), (2) counter-axial field and co-axial current (counter-helicity), (3) co-axial field and counter-axial current (counter-helicity), and (4) counter-axial field and counter-axial current (co-helicity). Except case 3, each case is found to be related with certain eruptive features.

• Journal of the Korean Electrochemical Society
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• v.11 no.3
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• pp.165-169
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• 2008

The effect of reduction of carbon dioxide by CODH(Carbon Monoxide Dehydrogenase) was compared on glassy carbon and gold working electrodes. In case of gold electrode, the choice of the optimum applied potential is very important since $H_2$ evolution can be mixed with $CO_2$ reduction. On the other hand, efficient $CO_2$ reduction was observed up to -650 mV vs. NHE on glassy carbon in neutral solution due to the larger overpotential for $H_2$ evolution on glassy carbon surface than that on gold surface. The optimum potential for $CO_2$ reduction was found to be $-570{\sim}600\;mV$ vs. NHE. The current efficiency of $CO_2$ to CO decreased dramatically at more negative potential according to the activity of enzyme decrease and the hydrogen evolution.

• Microbiology and Biotechnology Letters
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• v.14 no.5
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• pp.385-389
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• 1986

Both hydrogenase and nitrogenase were found to be involved in hydrogen evolution independently in Rhodopseudomonas sp. KCTC 1437. The hydrogen formation in this bacterium was independent on light illumination and presence of N $H_4^{+}$ After establishment of conditions to measure the amount of hydrogen evolved by each of the enzymes in vivo, the several factors affecting on the hydrogen evolution, e.g. presence of gases ( $C_2$ $H_2$, $H_2$, $O_2$ or $N_2$), C/N ratio, were investigated, Hydrogenase was less inhibited than nitrogenase under $O_2$ and was active independent on the presence of $N_2$ or $C_2$ $H_2$ which were the strong inhibitor of nitrogenase. Besides, the hydrogenase activity was increased after incubation with $H_2$. And it was verified that this bacterium consume hydrogen and photoreduce $CO_2$ by hydrogenase. From above results, it is concluded that hydrogenase in Rhodopseudomonas sp. KCTC 1437 can produce hydrogen under more favorable condition that nitrogenase.e.

• Journal of Nuclear Fuel Cycle and Waste Technology(JNFCWT)
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• v.20 no.4
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• pp.371-382
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• 2022

Carbonates are inorganic ligands that are abundant in natural groundwater. They strongly influence radionuclide mobility by forming strong complexes, thereby increasing solubility and reducing soil absorption rates. We characterized the spectroscopic properties of Am(III)-carbonate species using UV-Vis absorption and time-resolved laser-induced fluorescence spectroscopy. The deconvoluted absorption spectra of aqueous Am(CO₃)₂^- and Am(CO₃)₃^3- species were identified at red-shifted positions with lower molar absorption coefficients compared to the absorption spectrum of aqua Am³⁺. The luminescence spectrum of Am(CO₃)₃^3- was red-shifted from 688 nm for Am³⁺ to 695 nm with enhanced intensity and an extended lifetime. Colloidal Am(III)-carbonate compounds exhibited absorption at approximately 506 nm but had non-luminescent properties. Slow formation of colloidal particles was monitored based on the absorption spectral changes over the sample aging time. The experimental results showed that the solubility of Am(III) in carbonate solutions was higher than the predicted values from the thermodynamic constants in OECD-NEA reviews. These results emphasize the importance of kinetic parameters as well as thermodynamic constants to predict radionuclide migration. The identified spectroscopic properties of Am(III)-carbonate species enable monitoring time-dependent species evolution in addition to determining the thermodynamics of Am(III) in carbonate systems.

• The Bulletin of The Korean Astronomical Society
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• v.44 no.2
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• pp.39.3-39.3
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• 2019

Ram pressure stripping due to the intracluster medium (ICM) is an important environmental process, which causes star formation quenching by effectively removing cold interstellar gas from galaxies in dense environments. The evidence of diffuse atomic gas stripping has been reported in several HI imaging studies. However, it is still under debate whether molecular gas (i.e., a more direct ingredient for star formation) can be also affected and/or stripped by ram pressure. The goal of this thesis is to understand the impact of ram pressure on the molecular gas content of cluster galaxies and hence star formation activity. To achieve this, we conducted a series of detailed studies on the molecular gas properties of three Virgo spiral galaxies with clear signs of active HI gas stripping (NGC 4330, NGC 4402, and NGC 4522) based on high-resolution CO data obtained from the Submillimeter Array (SMA) and Atacama Large Millimeter/submillimeter Array (ALMA). As a result, we find the evidence that the molecular gas disk also gets affected by ram pressure in similar ways as HI even well inside of the stellar disk. In addition, we detected extraplanar 13CO clumps in one of the sample, which is the first case ever reported in ram pressure stripped galaxies. By analyzing multi-wavelength data (e.g., Hα, UV, HI, and CO), we discuss detailed processes of how ram pressure affects star formation activities and hence evolution of cluster galaxies. We also discuss the origin of extraplanar 13CO, and how ram pressure can potentially contribute to the chemical evolution of the ICM.