• Journal of the Korean Crystal Growth and Crystal Technology
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• v.4 no.3
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• pp.315-324
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• 1994

The effects of impurities of the quartz raw materials on the trasformation of quartz to cristobalite were investigated. As the increase of impurities content, the amount of cristobalite crystal increased, whereas the fusion temperature of quartz and the formation temperature of cristobalite decreased. And the courses of the transformation of quartz to cristobalite were examined. The course of quartz $\rightarrow$ transitional noncrystalline phase $\rightarrow$ melt (T) and quartz $\rightarrow$ transitional noncrystalline phase $\rightarrow$ cristobalite $\rightarrow$ melt (C) were always coexisted on the transformation of quartz. In the case of high purity quartz raw material, the T course was predominant, while in low purity quartz raw material, the C course was predominant. And the calculated density of heat treated sand by the quantitative analysis of quartz and cristobalite phase by XRD is well agreed with the measured density by pycnometer. On the melting proces of quartz glass, the volume expansion of sand at a certain temperature can be estimated with the calculated density data.

• Korean Journal of Food Science and Technology
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• v.24 no.5
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• pp.477-481
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• 1992

As a series of fundamental research projects to produce doenjang (Korean fermented soy paste) of better quality, two kinds of doenjang were manufactured from a traditional meju (Korean soy bean koji) and the mixed with Aspergillus oryzae and Bacillus natto, and histological changes in the cell structures of soy bean of the two were reported doenjang samples were observed and compared during the entire period of fermentation processes. Cell walls of the soy bean were ruptured by pressure and heat during the pressure cooking process and some of them were observed to have the ghost-like shapes. Remarkable differences in the plasmolysis of the cytoplasms were observed between the seed coat and the inner part of soy bean. Small vacuoles resulting from the fusion of the glycoprotein globules by protease and from the hydrolysis of the starch granules by amylase were also observed. Penetration of microorganisms was transferred from the seed coat to the inside of soy bean as the fermentation proceeded. Slimy substances were observed on the seed coat and the parenchyma cells of soy bean fermented with the mixed with Aspergillus oryzae and Bacillus natto. Cell walls of soy bean became difficult to stain and they showed unusual, polygonal shapes as the fermentation proceeded. Samples fermented with the mixed with Aspergillus oryzae and Bacillus natto showed more remarkable tendencies than traditional meju.

• BMB Reports
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• v.45 no.6
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• pp.331-336
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• 2012

The retinoid-related orphan nuclear receptor gamma ($ROR{\gamma}$) plays critical roles in regulation of development, immunity and metabolism. As transcription factor usually forms a protein complex to function, thus capturing and dissecting of the $ROR{\gamma}$ protein complex will be helpful for exploring the mechanisms underlying those functions. After construction of the recombinant tandem affinity purification (TAP) plasmid, pMSCVpuro $ROR{\gamma}$-CTAP(SG), the nuclear localization of $ROR{\gamma}$-CTAP(SG) fusion protein was verified. Following isolation of $ROR{\gamma}$ protein complex by TAP strategy, seven candidate interacting proteins were identified. Finally, the heat shock protein 90 (HSP90) and receptor-interacting protein 140 (RIP140) were confirmed to interplay with $ROR{\gamma}$ by co-immunoprecipitation. Interference of HSP90 or/and RIP140 genes resulted in dramatically decreased expression of CYP2C8 gene, the $ROR{\gamma}$ target gene. Data from this study demonstrate that HSP90 and RIP140 proteins interact with $ROR{\gamma}$ protein in a complex format and function as co-activators in the $ROR{\gamma}$-mediated regulatory processes of HepG2 cells.

• Environmental Engineering Research
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• v.16 no.3
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• pp.159-164
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• 2011

This study examined the emission characteristics of impure gas-like hydrogen sulfide and siloxane contained in landfill gas (LFG) and investigated the effect of impure gas on LFG utility facilities. As a result of an LFG component analysis from eight landfills in the same environment, hydrogen sulfide averaged 436 ppmv (22-1,211 ppmv), and the concentration of total siloxane averaged 7.95 mg/$m^3$ (1.85-21.18 mg/$m^3$). In case of siloxane concentration by component, the ratio of D4 (average 3.79 mg/$m^3$) and D5 (average 2.64 mg/$m^3$) indicated the highest level. Different kinds of scales were found on the gas air heater (GAH) and inside the boiler. The major component of scale from the GAH was $Fe_2O_3$ of 38.5%, and it was caused by hydrogen sulfide. Other scale was found on the bottom and the wall of the boiler and the scale was silicon dioxide of 92.8% and 98.9%. The silicon dioxide scale was caused by combustion of siloxane. As a result of a scanning electron microscopy analysis, the structure of the silicon dioxide scale from the boiler was an immediate filamentous type. Consequently, as silicon dioxide scale is bulky, such bad effects were worsening, as an interruption in heat conduction, increase in fuel consumption, damage to the boiler by overheating, and clogged emission pipeline could occur in LFG utility facilities.

• Transactions of the Korean hydrogen and new energy society
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• v.26 no.2
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• pp.114-119
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• 2015

Nowdays, fossil fuels have been used as an important resource in development of industry. But it is limited and caused climate change such as pollution and global warming. So nuclear fusion research is being issued with tritium to develop eco-friendly and sustainable energy. Republic of Korea is in charge of Storage and Delivery System (SDS) in the International Thermonuclear Experimental Reactor (ITER), weld present in the SDS bottles are easily exposed to the hydrogen embrittlement of special characteristics of the hydrogen in hydrogen atmosphere, When the hydrogen embrittlement is rapidly progresses, the cracking is generated in the weld zone. Due to this cracking, the risk of leakage of tritium into the atmosphere occurs. In this study, hydrogen heat treatment was processed through the Pressure-Composition-Temperature (PCT) device according to the time variation. Also mechanical properties such as rupture strength test, three point bend test and hardness test in accordance with the respective time have been conducted and the fracture was observed by scanning electron microscopy(SEM) after the mechanical properties evaluation.

• Journal of the Korean Institute of Gas
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• v.5 no.3 s.15
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• pp.15-22
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• 2001

Reliability evaluation of welded structures by mechanical testing of weld heat-affected zones (HAZs) has become general practice throughout the world. HAZs of steel welded Joints show a gradient of microstructure from the fusion line to the unaffected base metal. This study is concerned a correlation between the microstructural change and the fracture characteristics in HAZs of both seam and girth welds of API 5L X65 pipeline steel, which is generally used for natural gas transmission pipelines in Korea. The focus in this study is the investigation of macroscopic fracture behavior of the various regions within HAZ. Changes in microstructure and toughness were observed using actual HAZ specimens. To evaluate the macroscopic toughness of actual HAZ, Charpy V-notch impact test and CTOD test were performed.

• Progress in Superconductivity and Cryogenics
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• v.25 no.4
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• pp.70-74
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• 2023

The Small Punch Test (SPT) was developed to evaluate the softening and embrittlement of materials such as power plants and nuclear fusion reactors by taking samples in the field. Specimens used in the SPT are very thin and small disk-shaped compared to specimens for general tensile test, and thus have economic advantages in terms of miniaturization and repeatability of the test. The cryogenic SPT can also be miniaturized and has a significantly lower heat capacity than conventional universal test machines. This leads to reduced cooling and warm-up times. In this study, the cryogenic SPT was developed by modifying the existing room temperature SPT to be cooled by liquid nitrogen using a super bellows and a thermal insulation structure. Since the cryogenic SPT was first developed, basic experiments were conducted to verify the effectiveness of it. For the validation, aluminum alloy 6061- T6 specimens were tested for mechanical properties at room and cryogenic temperature. The results of the corrected tensile properties from the SPT experiment results were compared with known room temperature and cryogenic properties. Based on the correction results, the effectiveness of the cryogenic SPT test was confirmed, and the surface fracture characteristics of the material were analyzed using a 3d image scanner. In the future, we plan to conduct property evaluation according to the development of various alloy materials.

• Molecules and Cells
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• v.20 no.1
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• pp.142-150
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• 2005

Members of the multifunctional Cyp family have been isolated from a wide range of organisms. However, few functional studies have been performed on the role of these proteins as chaperones in red alga. For studying the function of cDNA GjCyp-1 isolated from the red alga (Griffithsia japonica), we expressed and purified a recombinant GjCyp-1 containing a hexahistidine tag at the amino-terminus in Escherichia coli. An expressed fusion protein, $H_6GjCyp-1$ maintained the stability of E. coli proteins up to $50^{\circ}C$. For a functional bioassay for recombinant $H_6GjCyp-1$, the viability of E. coli cells overexpressing $H_6GjCyp-1$ was compared with that of cells not expressing $H_6GjCyp-1$ at $50^{\circ}C$. After high temperature treatment for 1 h, E. coli overexpressing $H_6GjCyp-1$ survived about three times longer than E. coli lacking $H_6GjCyp-1$. Measurement of the light scattering of luciferase (luc) showed that GjCyp-1 prevents the aggregation of luc during mild heat stress and that the thermoprotective activity of GjCyp-1 is blocked by cyclosporin A (CsA), an inhibitor of Cyps. Furthermore, the Cyp-CsA complex inhibited the growth of E. coli under normal conditions. The results of the GjCyp-1 bioassays as well as in vitro studies strongly suggest that Cyp confers thermotolerance to E. coli.

• Journal of the Korean Association of Geographic Information Studies
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• v.14 no.1
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• pp.107-117
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• 2011

This study aimed to inquire into possibilities of the web-based representation of thematic maps by geo-information mashup in the geoweb platform. In the Web2.0, Google platform leads the geoweb by offering effective mashup functions for geo-information. Geo-information mashup is opening a new horizon of map applications in fusion with a great of data in the Internet. Geo-information mashup by the available data method can be classified as two type; one is linkage of sources of platform itself(satellite images) and external data, the other is linkage of platform itself and user created contents. This study made heatmap, proportional map, and choropleth map based on Google satellite images by the linkage of platform itself and external data. As a result, thematic map of Google mashup expected to give us to a flexibility for difference interpretations of geographical distribution by representing overlap with satellite images.

• Korean Journal of Acupuncture
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• v.29 no.2
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• pp.260-270
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• 2012

Objectives : Hippocampus, a region of temporal lobe, plays an important role in the pathogenic mechanisms of brain diseases such as Alzheimer's disease, depression and temporal lobe epilepsy. This research is designed to investigate hippocampal changes after acupuncture stimulation at Shinmun(HT7) using 2-dimensional gel electrophoresis(2-DE). Methods : On postnatal-day 15, rat pups were randomly devided into Normal(NOR) or HT7 group. All of Pups kept with their mothers for 7 days, but pups in HT7 group received acupuncture stimulation at HT7 daily. On postnatal-day 21, hippocampus of each rat pup was dissceted 30 minutes after last acupuncture stimulation and the protein expressions were investigated using 2-DE. Results : After acupuncture stimulation at HT7, expression of 20 proteins were significantly increased. Succinate semialdehyde dehydrogenase, glyceraldehyde-3-phosphate dehydrogenase-like, transketolase, aconitate hydratase and phosphoglucomutase-1 were related to glucose methabolism. Eukaryotic initiation factor(eIF) 4A-II, eIF 4A-III, mitochondrial Tu translation elongation factor and chain A of crystal structure of the 70-Kda heat shock cognate protein involve in the protein synthesis in ribosome. Tubulin ${\beta}$-4 chain, tubulin T ${\beta}$-15 and tubulin ${\alpha}$-1B chain comprise cytoskeleton. Glutathione S-transferase(GST) ${\omega}$-1, GST P and GST Yb-3 can reduce oxidative stress. ${\beta}$-soluble N-ethylmaleimide-sensitive fusion protein attachment protein is required for vesicular transport between the endoplasmic reticulum and the Golgi apparatus, glycerol-3-phosphate dehydrogenase plays a major role in lipid biosynthesis, creatine kinase U-type catalyses the conversion of creatine and consumes adenosine triphosphate to create phosphocreatine and adenosine diphosphate. Platelet-activating factor acetylhydrolase IB subunit alpha and voltage depedent anion-selective channel protein 2 were also increased. Conclusions : The results suggest that acupuncture stimulation at HT7 may enhance glucose and lipid metabolism, protein synthesis, cytoskeletal substance and anti-oxidative stress in hippocampus.