• Proceedings of the Membrane Society of Korea Conference
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• 2004.05b
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• pp.180-183
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• 2004

Gas separation membranes are now used in a wide variety of application areas as oxygen enrichment, hydrogen recovery, acid gas treatment, and natural gas dehydration etc [1]. Since polymeric membranes offer attractive properties for gas separation application, they have been variously studied [2-4].(omitted)

• Advances in Energy Research
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• v.3 no.2
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• pp.125-131
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• 2015

Prompt neutron lifetime calculations have been performed for the NIRR-1 reactor HEU and LEU cores using the 1/v insertion and the Adjoint flux weighing methods. Results of calculations obtained for the HEU and LEU cores are respectively $57.3{\pm}0.8$ and $47.5{\pm}0.7$ for the 1/v insertion and $56.9{\pm}0.3$ and $46.3{\pm}0.5$ for the Adjoint flux. There is a good agreement seen between the two methods for both cores. The prompt neutron lifetime was observed to be shorter in the LEU than for the HEU as expected. However, the Adjoint flux weighing method seemed to be the easiest method in calculating the prompt neutron lifetime for NIRR-1.

• Mass Spectrometry Letters
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• v.12 no.4
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• pp.163-171
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• 2021

Emiliania huxleyi is a marine phytoplankton that plays a critical role in global carbon and sulfur cycling. The genome of E. huxleyi has been sequenced, and an in-depth proteomic profile of this organism has been reported. This study analyzed the phosphoproteome of E. huxleyi and identified its changes under calcium-limited conditions. A TiO₂ microcolumn was used for phosphopeptide enrichment, followed by liquid chromatography-tandem mass spectrometry analysis. Overall, we identified 7,010 phosphorylated sites on 3,355 phosphopeptides associated with 2,929 phosphoproteins in E. huxleyi. Quantitative analysis revealed changes in the phosphoproteome in E. huxleyi when ambient conditions changed to calcium-limited conditions, notably the phosphorylation of some transporters was altered. This study provides an overview of protein phosphorylation in E. huxleyi and paves the way for further investigations of its biological functions.

• Corrosion Science and Technology
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• v.18 no.2
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• pp.49-54
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• 2019

The purpose of this paper is to present failure analysis, of the heat exchanger tube in a district heating system. SS304 stainless steel is used, as material for the heat exchanger tube. The heat exchanger operates in a soft water environment containing a small amount of chloride ions, and regularly repeats operation and standstill period. This causes concentration of chloride ions on the outer surface of the tube, as well as repeat of thermal expansion, and shrinkage of the tube. As a result of microscopic examination, cracks showed transgranular as well as branched propagation, and many pits were present, at the initiation point of each crack. Energy disperstive spectroscopy analysis showed Fe and O peak, as well as Cl peak, meaning that cracks were affected by Cl ion. Failure of the tube was caused by chloride-induced stress corrosion cracking by thermal stress, high temperature, and localized enrichment of chloride ions.

• Journal of the Mineralogical Society of Korea
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• v.17 no.4
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• pp.357-364
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• 2004

Mineral chemistry of talc from the Dongyang talc deposits was studied to characterize the differences between dolomite-origin talc (talc I) and tremolite-origin talc (talc II). Average iron and aluminum contents are higher in talc II, 2.18 wt% FeO and 0.31 wt% $Al_2$O$_3$), than in talc I, 1.48 wt% FeO and 0.08 wt% $Al_2$O$_3$). Consistently lower Mg/(Mg+Fe+Mn) ratios and higher AI concentrations with uniform values of talc II compared to talc I seem to reflect the compositional differences of the original materials, tremolite and dolomite, respectively. Relative enrichment of Al as well as Fe in talc II compared to tremolite can be attributed to their immobile behaviors during alteration process and the rapid diffusion of hydrothermal fluids, which can accelerate instantaneous nucleation with immaturity growth of talc II. Increase in the concentrations of talc II can lower the ore grade by increasing concentrations of impure components such as AI and Fe, and by abundant presence of tremolite as well.

• YAKHAK HOEJI
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• v.59 no.3
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• pp.113-119
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• 2015

Protein phosphorylation is one of most important post-translational modifications (PTMs) and plays an important role in regulation of protein function. Here we develop a method for a global identification of phosphopeptides and phosphorylation sites using nano-LC MS/MS. We compared two separation methods, C4 and strong cation ion exchange (SCX). Before phosphopeptides enrichment with $TiO_2$, total proteins from Rat 1 cells have been separated using C4 column or tryptic peptides of proteins from the cells have been separated using SCX column. Finally, we have detected 52 phosphorylation sites on 41 proteins from SCX method and 375 phosphorylation sites on 252 proteins from C4 method, and determined the function and localization of identified phosphoproteins using DAVID software. In particular, we showed new phosphorylation sites from membrane proteins related to various cell signaling mechanisms. This method may contribute to study global signal networks induced by various signals including ligands and drugs.

• Bulletin of the Korean Chemical Society
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• v.35 no.2
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• pp.383-391
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• 2014

Biotin-S-S-Phosphine was designed and synthesized as a potential tool for a proteomic study of O-GlcNAcmodified proteins. This reagent features a disulfide linker between a triarylphosphine moiety, which allows selective conjugation to azide-containing proteins, and a biotin moiety that can allow easy isolation through its strong affinity toward avidin-coated solid beads. The disulfide linkage within this reagent can allow the easy release of the bound molecules of interest, which is difficult to achieve when a biotin:avidin pair is used alone, by reducing the disulfide bond of the reagent with DTT. Preliminary in vitro biological assays with azidelabeled and unlabeled cell lysates and a pure protein Nup62 showed that the Biotin-S-S-Phosphine reagent is highly reactive toward the free thiol groups of proteins. When a molecular tool with a disulfide linker is applied to the enrichment of the molecules of interest from other species, it is important to block the free-thiols of the sample using exhaustive alkylation prior to the Staudinger ligation reactions to restore the bioorthogonal nature of this reaction.

• Journal of Korean Society of Environmental Engineers
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• v.29 no.1
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• pp.23-30
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• 2007

The ultimate objective of this study is to develop oxygen-enriched combustion techniques applicable to the system of practical industrial boiler. To this end the combustion characteristics of lab-scale LNG combustor were investigated as a first step using the method of numerical simulation by analyzing the flame characteristics and pollutant emission behaviour as a function of oxygen enrichment level. Several useful conclusions could be drawn based on this study. First of all, the increase of oxygen enrichment level instead of air caused long and thin flame called laminar flame feature. This was in good agreement with experimental results appeared in open literature and explained by the effect of the decrease of turbulent mixing due to the decrease of absolute amount of oxidizer flow rate by the absence of the nitrogen species. Further, as expected, oxygen enrichment increased the flame temperatures to a significant level together with concentrations of $CO_2$ and $H_2O$ species because of the elimination of the heat sink and dilution effects by the presence of $N_2$ inert gas. However, the increased flame temperature with $O_2$ enriched air showed the high possibility of the generation of thermal $NO_x$ if nitrogen species were present. In order to remedy the problem caused by the oxygen-enriched combustion, the appropriate amount of recirculation $CO_2$ gas was desirable to enhance the turbulent mixing and thereby flame stability and further optimum determination of operational conditions were necessary. For example, the adjustment of burner with swirl angle of $30\sim45^{\circ}$ increased the combustion efficiency of LNG fuel and simultaneously dropped the $NO_x$ formation.

• Nuclear Engineering and Technology
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• v.24 no.2
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• pp.141-153
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• 1992

Excess tritium analysis was peformed to verify whether or not cold fusion occurs during electrolysis of heavy water in the current density range of 83~600 mA/$\textrm{cm}^2$ for a period of 24 ~ 48 hours with use of palladium electrodes of seven different processing treatments and geometries. The extent of recombination of D$_2$ and $O_2$gases in the electrolytic cell was measured for the calculation of accurate enthaplpy values. The behavior and interaction of hydrogen atoms with defects in Pd electrodes were examined using the Sieverts gas charging and the positron annihilation(PA) method. Slight enrichment of tritium observed was attributed to electrolytic enrichment but not to the formation of a by-product of cold fusion. The extent of recombination of D$_2$and $O_2$gases was 32%. Hence the excess heat measured during the electrolysis was considered to be due to the exothermic reaction of recombination but not to nuclear fusion. Lifetime results from the PA measurements on the Pd electrodes indicated that hydrogen atoms could be trapped at dislocations and vacancies in the electrodes and that dislocations were slightly more preferred sites than vacancies. It was also inferred from R parameters that the formation of hydrides was accompanied by generation of mostly dislocations. Doppler broadening results of the Pd electrodes indicated that lattiec defect sites where positrons were trapped first increased and then decreased, and this cycle was repeated as electrolysis continued. It can be inferred from PA measurements on the cold-rolled Pd and the isochronally annealed Pd hydride specimens that microvoid-type defects existed in the hydrogen-charged electrode specimen.

• Ocean and Polar Research
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• v.36 no.4
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• pp.407-421
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• 2014

The benthic environmental impact experiment addresses environmental impacts at a specific site related to deep-sea mineral resource development. We have acquired several tens of multi- or box core samples at 31 sites within the Benthic environmental Impact Site (BIS) since 2010, aiming to examine the basic properties of surficial deep-sea sediment as a potential source for deep-water plumes. In this study, we present the geochemical properties such as major elements, rare earth elements (REEs), and heavy metal contents at the BIS. Such proxies vary distinctly according to the Facies association. The lithology of all core sediments in the BIS corresponds to both Association Ib and Association IIIb. The vertical profiles of some major elements ($SiO_2$, $Fe_2O_3$, CaO, $P_2O_5$, MgO, MnO) show noticeable differences between Association Ib and IIIb, while others ($Al_2O_3$, $TiO_2$, $Na_2O$, and $K_2O$) do not vary between Association Ib and IIIb. REEs are also distinctly different for Associations Ib and IIIb; in Association Ib, REY and HREE/LREE are uniform through the sediment section, while they increase downward in Association IIIb like the major elements; below a depth of 8 cm, REY is over 500 ppm. The metal enrichment factor (EF) evaluates the anthropogenic influences of some metals (Cu, Ni, Pb, Zn, and Cd) in marine sediments. In both Associations, the EF for Cu is over 1.5, the EF for Ni and Pb ranges from 0.5 to 1.5, and the EF for Zn and Cd are less than 0.5, indicating Cu is enriched but Zn and Cd are relatively depleted in the BIS. The vertical variations of geochemical properties between Association Ib and IIIb are shown to be clearly different, which seems to be related to the global climate changes such as the shift of Intertropical convergence zone (ITCZ).