• Journal of the Korean Wood Science and Technology
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• v.44 no.5
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• pp.716-725
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• 2016

In this study, MCQ (Micronized copper Quat) which was copper-based wood preservative, was investigated on decay properties by difference of the its infiltration volume. After pressure-treatment with different MCQ concentration, test specimens (Japanese Red Pine) were exposed by a brown-rot fungus (Fomitopsis palustris). At the end of the 12 weeks exposure to the fungus, untreated specimen was showed the mass loss of more than 35%, and the value of preservative effectiveness of MCQ by indoor decay was $3.99{\pm}0.42kg/m^3$. Therefore, MCQ should be pressure-injected at least $3.99kg/m^3$. The three dimensional of the specimens were observed by using the light microscope and scanning electron microscope, Untreated and treatment specimens with low concentration generally had underwent serious decays and had a lot of fungal hyphae. Howere, the formation of bore hole by hyphae were not observed. Mass loss and decay properties of specimens were affected by amount of MCQ injection. Therefore, it is necessary to the review of the adequacy of the MCQ injection amount in domestic environments.

• 대한예방의학회:학술대회논문집
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• 2005.10a
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• pp.360-360
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• 2005

• Journal of the Korean Vacuum Society
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• v.6 no.4
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• pp.314-320
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• 1997

A chemical reaction and electronic structure change at the interface between copper and titanium nitride were investigated by XPS. A thin Cu layer was deposited on a TiN substrate oxidized by exposure to air at room temperature. We observed the Ti(2p), O(1s), N(1s), Cu(2p) core-level, and Cu LMM Auger line spectra. With increasing of the thickness of Cu layer, these spectra do not show any changes in the line shape as well as in peak position. In addition, the valence band spectra in XPS do not show any changes, which indicates that Cu does not react with Ti, N, and O. This inreactivity of Cu might cause a poor adhesion between Cu and TiN.

• Computers and Concrete
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• v.5 no.6
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• pp.509-524
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• 2008

Containment structures not only are leak-tight barriers, but also may be subjected to impacts caused by tornado-generated projectiles, aircraft crashes or the fragments of missile warhead. This paper presents the results of an experimental study of the impact resistance of steel fiber-reinforced concrete against 45 g projectiles at velocity around 2500 m/s. An explosively formed projectile (EFP) was designed to generate an equivalent missile fragment. The formation and velocity of EFP are measured by flash x-ray. A switch made of double-layered thin copper sheets controlled the exposure time of each flash x-ray. The influence of the fiber volume fraction on the crater diameter of concrete slab and the residual velocity of the projectile were studied. The residual velocity of the projectile decreased as the fiber volume fractions increased. In this work, the residual velocity of the projectile was to 44% that of plain concrete when the fiber volume fraction exceeded 1.5%. Based on the present finding, steel fiber reinforced concrete with the fiber volume fraction exceeding 1.5% appear to be more efficient in protection against high velocity fragment impact.

• The Transactions of The Korean Institute of Electrical Engineers
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• v.63 no.6
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• pp.770-775
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• 2014

According to ICNIRP guidelines for limiting exposure to time-varying electric, magnetic and electromagnetic fields up to 300GHz, magnetic flux density which range from 3Hz to 150kHz are regulated to lower than $6.25{\mu}T$. In order to comply with its standard, OLEV(On-Line Electric Vehicle) have been designed considering EMF(Electro-Magnetic Field) reduction. However, if a current flowing in power line would be bigger for increasing power transfer efficiency, the established shield system no longer acts their role properly. In this paper, therefore, FCCL(Flexible Copper Clad Laminate) is applied to power line and pick-up devices to solve the problems. Though, the FCCL is normally utilized to insulator on circuit board, because of its high heat resistance characteristic, flexibility and thin properties, it makes effectiveness in the shielding device as well. 4 types of FCCL shielding structure are introduced to power line and pick-up devices. From the results, the FCCL which are placed in proposed positions shows maximum EMF reduction compared to the established shielding structure. Henceforth, if OLEV is applied FCCL shielding structure in practice, it will not only be more safe but also step forward to commercialization near future.

• Journal of Ginseng Research
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• v.32 no.2
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• pp.114-119
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• 2008

Terpene synthase plays a key role in biosynthesis of triterpene saponins (ginsenosides) and is intermediate in the biosynthesis of a number of secondary metabolites. A terpene synthase (PgTPS) cDNA was isolated and characterized from the root of Panax ginseng c.A. Meyer. The deduced amino acid sequence of PgTPS showed a similarity with A. deliciosa (AAX16121) 61%, V. vinifera (AAS66357) 61%, L. hirsutum (AAG41891) 55%, M. truncatula (AAV36464) 52%. And the segment of a terpene synthase gene was amplified by reverse transcriptase-polymerase chain reaction (RTPCR). We studied expression of terpene synthase under stressful conditions like chilling, salt, UV, and heavy metal stress treatment. Expression of PgTPS was increased gradually after exposure to stresses such as chilling, salt, and UV illumination. But its transcription seems to be reduced by cadmium and copper treatment.

• YAKHAK HOEJI
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• v.49 no.1
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• pp.86-91
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• 2005

Flavonoids are class of polyphenolic compounds widely distributed in the plant kingdom, which display a variety of biological activities, including antiviral, antithrombotic, antiinflammatory, antihistaminic, antioxidant and free-radica 1 scavenging abilities. The antioxidant enzyme (AOE) system plays an important role in the defense against oxidative stress insults. To determine whether flavonoid, myricetin can exert antioxidative effects not only directly by modulating the AOE system but also scavenging free radical, we investigated the influence of the flavonoid myricetin on cell viability, different antioxidant enzyme activities, ROS level and the expression of different antioxidant emzyme in B16F10 murine melanoma cells. Myricetin in a concentration range from 6.25 to $50\;{\mu}M$ decreased superoxide dismutase (SOD) and glutathione peroxidase (GPx) enzyme activities, but catalase (CAT) activity was increased. In the myricetin-treated group, ROS levels were decreased dose-dependently. Antioxidant enzyme expression was measured by RT-PCR. Myricetin treatment of B16F10 cells increased catalase expression. Expression levels of copper zinc superoxide dismutase (CuZn SOD) were not affected by exposure of myricetin. Manganese superoxide dismutase (Mn SOD) and GPx expression levels decreased slightly after myricetin treatment. In conclusion, the antioxidant capacity of myricetin was due to CAT and free-radical scavenging.

• Journal of Surface Science and Engineering
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• v.53 no.1
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• pp.29-35
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• 2020

In this study, five different specimen preparation methods were introduced and their advantages and disadvantages were presented. One of them, an epoxy mounting method has advantages of constant exposure area, ease of surface preparation without touching the specimen surface during polishing or cleaning, use of small amount of material and ease of specimen reuse by polishing or etching. However, in order to eliminate unexpected errors resulting from preferable reaction at the specimen/epoxy interface and contact resistance between the specimen and copper conducting line for electrical connection, it is recommended to cover the wall side of the specimen with porous anodic oxide films and to remain the contact resistance lower than 1 ohm. The increased contact resistance between the specimen and Cu conducting line appeared to result in increases of anodizing voltage and solution temperature during anodizing by which thickness and hardness of anodizing film on Al2024 alloy were drastically decreased and color of the films became more brightened.

• Biomolecules & Therapeutics
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• v.2 no.2
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• pp.136-140
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• 1994

To prove the hypothesis that NO- and N $O_2$-carrying molecules potentiate photorelaxation by generating NO, investigation was carried out using isolated rabbit and human corpus cavernosum. Corporal smooth muscle, in the presence or absence of endothelium, relaxed only slightly upon ultraviolet light (366 nm) irradiation. But, NO-and/or N $O_2$-containing compounds such as streptozotocin and $N^{G}$-nitro-L-arginine methyl ester significantly (p<0.01) enhanced photorelaxation in this tissue. In addition, $N^{G}$-nitro-D-arginine methyl ester, known to lack inhibitory action on NO synthase, showed concentration-dependent potentiation of the photorelaxation. Oxygen radical generating system via copper＋ascorbic acid and guanylate cyclase inhibitor, methylene blue, significantly (p<0.05) inhibited the streptozotocin-potentiated photorelaxation. Nitrite was accumulated by photolysis of streptozotocin, $N^{G}$-nitro-L-arginine methyl ester and $N^{G}$-nitro-D-arginine methyl ester, in a concentration and exposure time dependent manner. These observations indicate that NO is a potent relaxant of rabbit and human corpus cavernosum and further support the hypothesis that NO is released by photolysis from NO- and N $O_2$-carrying molecules.lecules.

• Food Science and Biotechnology
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• v.17 no.4
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• pp.842-845
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• 2008

This study was carried out to investigate the bactericidal efficacy of concentration (0.1, 0.2, and 0.4 ppm) and exposure time (10 and 30 min) of ozone on bacterial reduction rate of Salmonella typhimurium KCTC 2541 and Staphylococcus aureus ATCC 13515 in the distilled water (DW), and DW supplemented with 0.2% soluble starch (SS), and metal ion (MC) using argentums (Ag) and copper (Cu). The significant bactericidal differences of S. aureus were showed in the treatments of DW and SS, respectively, at the concentration of ozone above 0.1 ppm for 10 min, comparing the respective initial bacterial counts. The bacterial reduction of S. aureus was more sensitive than that of S. typhimurum at the same concentration of ozone. The bacterial reduction rate of SS treatment was slightly lower than that of DW treatment at the same concentration of ozone (p<0.05), however, the bacterial reduction rate of strains improved in the MC treatment compared to the DW treatment at the same concentration of ozone.