• Korean Journal of Organic Agriculture
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• v.22 no.4
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• pp.825-839
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• 2014

Antioxidant activity is important for reducing oxidative stress that causes various metabolic disorders. Metabolic disorders are highly related to loss of productivity in livestock. Therefore, development of effective antioxidant compounds originating from plants is important for organic agriculture. Phenolic compounds in edible plants are regarded as major components relevant to antioxidant activity. The present study investigated the changes in antioxidant activity and phenolic compound profiles of Aronia (Aronia meloncarpa) by fermentation using different strains of Leuconostoc mesenteroides. A total of 5 strains of L. mesenteroides were used as starter cultures and their ${\beta}$-glucosidase activities were measured. A total of 6 experiment runs were prepared, one for control (uninoculated) and the others (inoculated) for treatments. For biological activity, antioxidant and antibacterial activities were measured. For phenolic compound profiling, TLC and HPLC analysis were performed. The strains of KACC12313 and KACC12315 showed greater enzyme activity than others. Treatment with KCCM35046 showed strong and broad antibacterial activity against to Listeria monocytogenes. Treatments with KCCM35046 and KACC12315 showed the highest total polyphenol content. The highest antioxidant activity was found in KACC12315 treatment. No remarkable alteration was found in thin layer chromatography (TLC) analysis. In phenolic compound profiling analysis, KCCM35046 showed notable alteration in compound area ratio compared to others and also showed the highest caffeic acid content. In chlorogenic acid, treatments with KCCM35046 and KACC12315 showed great content than others. Treatment with KACC12315 showed the greatest content of trans-ferulic acid. As a result of relative performance indexing analysis, L. mesenteroides KCCM35046 and KACC12315 were selected as the best strain for the fermentation of Aronia.

• Journal of the Microelectronics and Packaging Society
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• v.28 no.4
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• pp.109-114
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• 2021

We investigated the effects of atmospheric hydrogen plasma treatment on Cu-Cu direct bonding. Hydrogen plasma was effective in reducing the surface oxide layer of Cu thin film, which was confirmed by GIXRD analysis. It was observed that larger plasma input power and longer treatment time were effective in terms of reduction and surface roughness. The interfacial adhesion energy was measured by DCB test and it was observed to decrease as the bonding temperature decreased, resulting in bonding failure at bonding temperature of 200℃. In case of wet treatment, strong Cu-Cu bonding was observed above bonding temperature of 250℃.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.19 no.10
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• pp.346-351
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• 2018

Metal three-dimensional (3D) printing technologies are mainly classified as powder bed fusion (PBF) and direct energy deposition (DED) methods according to the method of application of a laser beam to metallic powder. The DED method can be used to fabricate fine and hard 3D metallic structures by applying a strong laser beam to a thin layer of metallic powder. The PBF method involves slicing 3D graphics to be a certain height, laminating metal powders, and making a 3D structure using a laser. While the DED method has advantages such as laser cladding and metallic welding, it causes problems with low density when 3D shapes are created. The PBF method was introduced to address the structural density issues in the DED method and makes it easier to produce relatively dense 3D structures. In this paper, thin lines were produced by using PBF 3D printers with stainless-steel powder of roughly $30{\mu}m$ in diameter with a galvano scanner and fiber-transferred Nd:YAG laser beam. Experiments were carried out to find the optimal conditions for the width of a line depending on the processing times, laser power, spot size, and scan speed. The optimal conditions were two scanning processes in one line structure with a laser power of 30 W, spot size of $28.7{\mu}m$, and scan speed of 200 mm/s. With these conditions, a minimum width of about $85.3{\mu}m$ was obtained.

• Journal of the Korean Vacuum Society
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• v.17 no.6
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• pp.518-522
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• 2008

The miniaturization of device size and multilevel interlayers have been developed by ULSI circuit devices. These submicron processes cause serious problems in conventional metallization due to the solubility of silicon and metal at the interface, such as an increasing contact resistance in the contact hole and interdiffusion between metal and silicon. Therefore it is necessary to implement a barrier layer between Si and metal. Thus, the size of multilevel interconnection of ULSI devices is critical metallization schemes, and it is necessary reduce the RC time delay for device speed performance. So it is tendency to study the Cu metallization for interconnect of semiconductor processes. However, at the submicron process the interaction between Si and Cu is so strong and detrimental to the electrical performance of Si even at temperatures below $200^{\circ}C$. Thus, we suggest the tungsten-carbon-nitrogen (W-C-N) thin film for Cu diffusion barrier characterized by nano scale indentation system. Nano-indentation system was proposed as an in-situ and nanometer-order local stress analysis technique.

• Korean Journal of Veterinary Research
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• v.24 no.2
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• pp.149-162
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• 1984

The research was conducted(1) to confirm the agent(s) responsible for the antimicrobial activity contained in the fermented tomato juice with L. acidophilus(2) to extract and purify the antimicrobial agent(s)(3) to find the biological, physical and chemical properties of the agent(s). The following results were obtained and summarized as followings; 1. The agent responsible for the inhibitory activity was confirmed by both well assay method using fermented tomato juice with L. acidophilus and turbidimetric technique using the cell-free filtrate or neutralized filtrate of tomato acidohilus culture and found exerted antimicrobial agent other than lactic acid. 2. The procedures of purification : The isolation and purification of antimicrobial agent from the lyophilized acidophilus tomato culture were carried out by (1) methanol extraction (2) acetone extraction, (3) Sephadex G-50 gel filtration (4) paper chromatography and (5) thin layer chromatography. 3. The biological, physical and chemical properties of antimicrobial agent: The biological, physical, chemical properties of the purified antimicrobial agent were: (1) The antimicrobial activity was strong against test organisms; Bacillus subtilis(ATCC 6633), Escheichia coli(ATCC 25922), Staphylococcus aureus(ATCC 167), Pseudomonas fluorescens(KFCC 32394), Proteus vulgaris and Shigella dysenteriae. (2) The pH value of the agent was 2.0 and the inhibitory activity was lost when it was neutralized at 7.0 of pH and the agent was heat stable at $121^{\circ}C$ for 60 minutes. (3) The ultraviolet light absorption spectra of methanol-acetone extract and TLC fraction exhibited a maximum absorption at 260nm and 224nm respectively. (4) The most purified agent from TLC plate increased about 130-fold in activity. (5) The agent isolated from TLC plate was free from $H_2O_2$ or lactic acid. 4. Bioautographic assy: By means of bioautography of the agent on silica gel of TLC plate a strong inhibitory activity against B. subtilis was demonstrated. 5. Mass spectrometry: The agent obtained from TLC plate was analyzed by mass spectrometry which show the parent peak at m/e 264 suggesting the molecular weight of the compound and molecular group such as [$C_2H{^+}_4$], [CO], [CH=NH], [$C_3{H^}4_7$], [$\begin{array}{rcl}O\\{\parallel}\\CH_3-C\\\end{array}$], [$C_6-H{^+}_{11}$], [$C_5H{^+}_{11}$], [$\begin{array}{rcl}O\\{\parallel}\\C_5H_7-C^+\\\end{array}$] were suggested.

• Korean Journal of Materials Research
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• v.14 no.9
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• pp.607-613
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• 2004

This study was to investigate the surface properties of electrochemically oxidized Ti-6Al-7Nb alloy by anodic spark discharge technique. Anodizing was performed at current density 30 $mA/cm^2$ up to 300 V in electrolyte solutions containing $DL-{\alpha}$-glycerophosphate disodium salt hydrate($DL-{\alpha}$-GP) and calcium acetate (CA). Hydrothermal treatment was done at $300^{\circ}C$ for 2 hrs to produce a thin outermost layer of hydroxyapatite (HA). The bioactivity was evaluated from HA formation on the surfaces in a Hanks' solution with pH 7.4 at $36.5^{\circ}C$ for 30 days. The size of micropores and the thickness of oxide film increased and complicated multilayer by increasing the spark forming voltage. Needle-like HA crystals were observed on anodic oxide film after the hydrothermal treatment at $300^{\circ}C$ for 2 hrs. When increasing $DL-{\alpha}$-GP in electrolyte composition, the precipitated HA crystals showed the shape of thick and shorter rod. However, when increasing CA, the more fine needle shape HA crystals were appeared. The bioactivity in Hanks' solution was accelerated when the oxide films composed with strong anatase peak with presence of rutile peak. The increase of amount of Ca and P was observed in groups having bioactivity in Hanks' solution. The Ca/P ratio of the precipitated HA layer was equivalent to that of HA crystal and it was closer to 1.67 as increasing the immersion time in Hanks' solution.

• Proceedings of the Korea Association of Crystal Growth Conference
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• 1996.06a
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• pp.522-522
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• 1996

An investigation of the effects of transverse magnetic field and Peltier effect on melt convection and macrosegregation in vertical Bridgman crystal grosth of Te doped InSb was been carried out by means of microstructure observation, Hall measurement, electrical resistivity measurement and X-ray analysis. Before the experiments, Interface stability, convective instability and suppression of convection by magnetic field were calculated theoretically. After doping 1018, 1019 cm-3 Te in InSb, the temperature of Bridgman furnace was set up at $650^{\circ}C$. The samples were grown in I.D. 11mm, 100mm high quartz tube. The velocity of growth was about 2${\mu}{\textrm}{m}$/sec. In order to obtain the suppression of convection by magnetic field in the middle of growth, 2-4KG magnetic field was set on the melt. For searching of the shape of solid-liquid interface and the actual velocity of crystal growth, let 2A current flow from solid to liquid for 1second every 50seconds repeatedly (Peltier effect). The grown InSb was polycrystal, and each grain was very sharp. There was no much difference between the sample with and without magnetic field at a point of view of microstructure. For the sample with Peltier effect, the Peltier marks(striation) were observed regularly as expected. Through these marks, it was found that the solid-liquid interface was flat and the actual growth velocity was about 1-2${\mu}{\textrm}{m}$/sec. On the ground of theoretical calculation, there is thermosolutal convection in the Te doped InSb melt without magnetic field in this growth condition. and if there is more than 1KG magnetic field, the convection is suppressed. Through this experiments, the effective distribution coefficients, koff, were 0.35 in the case of no magnetic field, and 0.45 when the magnetic field is 2KG, 0.7 at 4KG. It was found that the more magnetic field was applied, the more convection was suppressed. But there was some difference between the theoretical calculation and the experiment, the cause of the difference was thought due to the use of some approximated values in theoretical calculation. In addition to these results, the sample with Peltier effect showed unexpected result about the Te distribution in InSb. It looked like no convection and no macrosegregation. It was thought that the unexpected behavior was due to Peltier mark. that is, when the strong current flew the growing sample, the mark was formed by catching Te. As a result of the phenomena, the more Te containing thin layer was made. The layer ruled the Hall measurement. The values of resistivity and mobility of these samples were just a little than those of other reference. It was thought that the reason of this result was that these samples were due to polycrystal, that is, grain boundaries had an influence on this result.

• Journal of Korean Society of Forest Science
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• v.27 no.1
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• pp.15-21
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• 1975

According to Yoshihisa Kuroki's report that the total amount of carotenoid was more in the susceptible to pine bark beetle, than in the resistant ones, carotenoids were extracted from needle leaves of one year old seedlings of Pinus thunbergii, Pinus desiflora, Pinus rigida, Pinus koraiensis, Pinus rigitaeda and Pinus taeda which are all important pines in Korea, to find their resistant ratio to the insect. The carotenoids were analyzed and compared using the spectra of them by spectrophotometer. The results were as follows: 1. The visible absorption spectra of carotenoids in those pine trees were proved to be very similar. 2. The total amount of carotenoids in needles differed with the tree species and the contents were arranged in decreasing order P. koraiensis>P. rigida>P. thunbergii>P. rigitaeda>P. taeda, it seemed that there was corelation between the cartenoid content and the extent of harm caused by the pine bark beetles except P. koraiensis. 3. But carotenoids were contained in Robinia pseudoacacia, Castanea crenata, Chamaecyparis obtusa and Cedrus deodra leaves too. 4. The total amounts of carotenoids in these pines of 9 species were arranged in decreasing order Robinia pseudoacacia>Pinus koraiensis>Pinus rigida>Pinus thunbergii>Castanea crenata>Pinus rigitaeda>Pinus taeda>Chamaecyparis obtusa>Cedrus deodara. Therefore, it was proved that there was no correlation between carotenoid cotent and extent of resistance to the insect. 5. In the thin-layer chromatography of these carotenoids, 13 kinds of components in P. densiftora, P. koraiensis and P. rigida and 12 kinds of spots in other pines, were detected respectively, under ultra-violet fluorescent lamp $3,600{\AA}$ and $2,537{\AA}$. 6. The eighth spots from the bottom in P. densiflora, P. koraiensis and P. rigida were not found in other pines and other 4 species (Robinia pseudoacacia, Castanea crenata, Chamacyparis obtusa, Cedrus deodra). Especially the spot in P. densiflora fluoresced strong cobalt blue-fluorescence under ultra-violet fluorescent lamp $2,537{\AA}$.

• Herbal Formula Science
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• v.11 no.2
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• pp.213-232
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• 2003

Objectives : This study was designed to establish a characteristic discrimination of internal and external morphological standard of original plants and herbal states in Arisaema amurense var. serratum $N_{AKAI}$ and A. amurense $M_{AXIM}.$. Methods : In this studies, the external-internal morphological standards were determined by using stereoscope and butanol series. Results : 1. In the external shape of original plant, Arisaema amurense var. serratum $N_{AKAI}$ has high stem, an oval-elliptic leaflet and a serrate leaf margin. But A. amurense $M_{AXIM}$ has a relatively low stem, an upside oval leaflet and no serrate leaf margin. 2. On the herbs character of original plant, Arisaema amurense var. serratum $N_{AKAI}$ is small in height and diameter, but A. amurense $M_{AXIM}$ is relatively large in height and diameter. 3. On the gathered herbs character of original plant, the section of Arisaema amurense var. serratum $N_{AKAI}$ is brightly white, easily spilt and strong scent. But the section of A. amurense $M_{AXIM}$ is thin yellowish brown, not easily spilt and weak scent. Also the grade of gathered herbs, both can be classified by diameter and external scent. 4. In the current herbs character, Korean and Sichuan Province products are irregullar shape and have no scent, Jilin Province products are regular shape. Also, Guangxi Province products are small size and concave in one side, Hebei Province products are irregular size and shape. 5. In internal shape of original plant, epidermal cell of Arisaema amurense var. serratum is very tight. With the except of micro difference in parenchyma cell of cortex, on the whole there are nearly no differences with A. amurense $M_{AXIM}.$ Also, samely in the internal shape, according to collecting sites, epidermis exhibits a lot layer in curving state and secreting duct is developed and vascular bundle and exists between parenchyma cell of cortex. Conclusion : In the future, additional study is needed to distinguish herb and effect between same genus-degree of relatedness.

• The Korean Journal of Petroleum Geology
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• v.11 no.1 s.12
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• pp.9-17
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• 2005

In the main target area of the block II, Targe-scale faults occur below the unconformity developed around 1 km in depth. The contrast of seismic velocity around the unconformity is generally so large that the strong multiples and the radical velocity variation would deteriorate the quality of migrated section due to serious distortion. More than 15 kinds of data processing techniques have been applied to improve the image resolution for the structures farmed from this active crustal activity. The bad and noisy traces were edited on the common shot gathers in the first step to get rid of acquisition problems which could take place from unfavorable conditions such as climatic change during data acquisition. Correction of amplitude attenuation caused from spherical divergence and inelastic attenuation has been also applied. Mild F/K filter was used to attenuate coherent noise such as guided waves and side scatters. Predictive deconvolution has been applied before stacking to remove peg-leg multiples and water reverberations. The velocity analysis process was conducted at every 2 km interval to analyze migration velocity, and it was iterated to get the high fidelity image. The strum noise caused from streamer was completely removed by applying predictive deconvolution in time space and ${\tau}-P$ domain. Residual multiples caused from thin layer or water bottom were eliminated through parabolic radon transform demultiple process. The migration using curved ray Kirchhoff-style algorithm has been applied to stack data. The velocity obtained after several iteration approach for MVA (migration velocity analysis) was used instead or DMO for the migration velocity. Using various testing methods, optimum seismic processing parameter can be obtained for structural and stratigraphic interpretation in the Block II, Yellow Sea Basin.