• Electrical & Electronic Materials
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• v.10 no.2
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• pp.113-118
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• 1997

For the amorphous F $e_{78}$ $B_{13}$S $i_{9-x}$G $e_{x}$ alloy, thermal analysis and measurements of the magnetic properties were carried out. As the content of Ge increased, the crystallization temperature was decreased and the Curie temperature was increased, and the tendencies were almost linear. The core loss of the amorphous alloy for x=1.7, field annealed at optimized condition, was 0.057 W/kg(l.0T, 60Hz), which was about 30% lower than that of no Ge added amorphous alloy (basic composition). Such a low core loss characteristics was thought to be caused by the lower coercive force and good squareness of B-H loop of the alloy.y.y.

• Journal of Dairy Science and Biotechnology
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• v.23 no.2
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• pp.115-123
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• 2005

Microcapsules consisting of natural, biodegradable polymers for controlled and/or sustained core release applications are needed. Physicochemical properties of whey proteins suggest that they may be suitable wall materials in developing such microcapsules. The objectives of the research were to develop water-insoluble, whey protein-based microcapsules containing a model water-soluble drug using a chemical cross-linking agent, glutaraldehyde, and to investigate core release from these capsules at simulated physiological conditions. A model water soluble drug, theophylline, was suspended in whey protein isolate (WPI) solution. The suspension was dispersed in a mixture of dichloromethane and hexane containing 1% biomedical polyurethane. Protein matrices were cross-linked with 7.5-30 ml of glutaraldehyde-saturated toluene (GAST) for 1-3 hr. Microcapsules were harvested, washed, dried and analyzed for core retention, microstructure, and core release in enzyme-free simulated gastric fluid (SGF) and simulated intestinal fluid(SIF) at $37^{\circ}C$. A method consisting of double emulsification and heat gelation was also developed to prepare water-insoluble, whey protein-based microcapsules containing anhydrous milkfat (AMF) as a model apolar core. AMF was emulsified into WPI solution (15${\sim}$30%, pH 4.5-7.2) at a proportion of 25${\sim}$50%(w/w, on dry basis). The oil-in-water emulsion was then added and dispersed into corn oil ($50^{\circ}C$) to form an O/W/O double emulsion and then heated at $85^{\circ}C$ for 20 min for gelation of whey protein wall matrix. Effects of emulsion composition and pH on core retention, microstructure, and water-solubility of microcapsules were determined. Overall results suggest that whey proteins can be used in developing microcapsules for controlled and sustained core release applications.

• Journal of the Korean institute of surface engineering
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• v.32 no.3
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• pp.423-427
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• 1999

Electroplating of 80%Ni permalloy thin plate for magnetic core materials. was studied The convected flow of electrolyte was used for stirring methode. The current density could be increased up to 250mA/$\textrm{cm}^2$ by flow cell. The composition of electroplated layer with vespect to current density and flow rate was investigated and experimental equation to predict the composition was made. How cell yielded more uniform thickness distribution than paddle cell did. The composition distribution was also studied. The thickness was the most important factor to the permeability. The permeability of 5$\mu\textrm{m}$plated permalloy was over 2000 at 1 MHz.

• Korean Journal of Environment and Ecology
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• v.29 no.2
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• pp.200-209
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• 2015

This study was conducted to investigate the distributional characteristics of ground beetles and to provide basis information for biodiversity management including the ground beetles in the Naejangsan National Park area. Pitfall traps were installed throughout 20 sites within Naejangsan National Park during 2008 to 2011 to collect ground beetles. A total of 2,409 collected ground beetles were identified with 35 species belonging to 19 genera of 8 subfamilies. Coptolabrus jankowskii jankowskii, Eucarabus sternbergi sternbergi, and Pterosticus audax were dominant at the core area, while Pheropsophus jessoensis, Synuchus nitidus, Synuchus cycloderus, and Chlaenius naeviger were dominant at the border of the National Park and adjacent to the road or grassland. These differences of dominant species also affected to the similarity of species composition between core and border area, and caused increasing dissimilarities between sites with cluster analysis. Although the result of the present study was a case study using ground beetles, it will be helpful to develop a management strategy of biodiversity conservation in Naejangsan National Park and its surroundings.

• Journal of the Korean Ceramic Society
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• v.33 no.7
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• pp.785-792
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• 1996

Formation of Solid Solution and Microstructure in Processureless sintered SiC-AlN compo-site using oxides as a sintering aid at 185$0^{\circ}C$ and 195$0^{\circ}C$ Regardless of SiC/AlN ratio in composition most of sintered specimens showed he complex structure mixed with 2H solid solution and SiC particles. High sintering temperature and large AlN content in starting composition enhanced the formation of 2H solid solution in sintered specimen 2H solid solution showed the spherical shape and core-rim structure. AlN content in the core is higher than that in the rim but SiC content . The size of 2H solid solution on fracture showed the transgranular fracture mode compared with the dispersed SiC particles which showed the intergranular fracture mode.

• Journal of Pharmaceutical Investigation
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• v.20 no.2
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• pp.89-95
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• 1990

Ethylcellulose-PEG 4000 film coated on core tablets was investigated as a potential drug delivery system for the controlled release of chlorpheniramine maleate (CPM). The kinetic analysis of the release data indicated that CPM release followed a diffusion-controlled model, where the quantity released per unit area is proportional to the square root of time. The effect of the film composition, CPM concentration, plasticizer concentration and CPM solubility on the release characteristics were examined. The release rate constant increased as CPM concentration increased. It also increased as the PEG 4000 content in the film increased above 10%(w/w), however, it decreased as the PEG 4000 content increased in the concentration range below 10%(w/w). The release rate constant was not affected by the coated weight on the core tablet. The film-coated tablets which contain CPM only in the coated film layer seemed to be a potential oral drug delivery system for the controlled release of CPM.

• Journal of Microbiology and Biotechnology
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• v.33 no.9
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• pp.1141-1148
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• 2023

Herein, we explored the potential of the apple's core microbiota for biological control of Erwinia amylovora, which causes fire blight disease, and analyzed the structure of the apple's bacterial community across different tissues and seasons. Network analysis results showed distinct differences in bacterial community composition between the endosphere and rhizosphere of healthy apples, and eight taxa were identified as negatively correlated with E. amylovora, indicating their potential key role in a new control strategy against the pathogen. This study highlights the critical role of the apple's bacterial community in disease control and provides a new direction for future research in apple production. In addition, the findings suggest that using the composition of the apple's core taxa as a biological control strategy could be an effective alternative to traditional chemical control methods, which have been proven futile and environmentally harmful.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.21 no.12
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• pp.115-119
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• 2020

Selective Laser Melting (SLM) technology is state-of-the-art additive manufacturing process technology that produces a three-dimensional structure by irradiating a laser on a fine metal powder to perform the fusion of a specific area and repeat this process. Owing to the characteristics of the additive manufacturing process, the melting phenomenon of the metal material by the laser has directionality depending on the process conditions, such as the irradiation direction of the laser and the build-up direction. For this reason, the composition of the metal material in the structure exhibits non-uniform characteristics. In this study, aluminum (AlSi10Mg) specimens were manufactured by applying SLM technology, and the material composition characteristics of the specimen were analyzed. The specimens were manufactured as cylinders by the build-up orientation of 0°, 45°, and 90°. The surface morphology of the specimen plane was analyzed optically. TEM analysis was performed on the core and the interface of the melting-pool inside the specimen generated by laser irradiation. The analysis results confirmed that there was a difference between the nano cell structure of the core and the interface of the melting-pool, and that the composition ratio of Si appeared higher at the interface than at the core of the cell.

• Korean Chemical Engineering Research
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• v.52 no.2
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• pp.209-213
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• 2014

A graft copolymer of poly(vinyl chloride)-g-poly(oxyethylene methacrylate) (PVC-g-POEM) was synthesized via atom transfer radical polymerization (ATRP) and used as a structure-directing agent to prepare $Al@Fe_2O_3$ core-shell nanocomposites through a sol-gel process. The amphiphilic property of PVC-g-POEM allows for good dispersion of Al particles and leads to specific interaction with iron ethoxide, a precursor of $Fe_2O_3$. Secondary bonding interaction in the sol-gel composites was characterized by Fourier transform-infrared (FT-IR) spectroscopy. The well-organized morphology of $Al@Fe_2O_3$ core-shell nanocomposites was observed using scanning electron microscopy (SEM) and transmission electron microscopy (TEM). Energy dispersive X-ray (EDX) and X-ray diffraction (XRD) were used to analyze the elemental composition and crystallization structure of the composites.

• Journal of Korean Society of Rural Planning
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• v.21 no.4
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• pp.27-33
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• 2015

Forest ecosystem is considered as an important stepping stone to minimize the impact of climate change. However, the rapid urbanization has caused fragmentation of forest ecosystem. The fragmentation of forest patch results in edge effect which brings about adverse impacts on forest function and structure. Degradation of forest ecosystem decreases carbon sequestration because edge effect reduces productivity. Therefore, we analyzed the impact of forest edge effect on forest ecosystem carbon stock change in Seongnam-si, Gyeonggi-do. We used connectivity analysis to determine forest edge and core area. The field study sites were selected with considering forest age, density, class and soil type. Secondly, forest carbon stock was calculated with allometric equation. The soil carbon stock was derived from Walkely-Black method. Lastly, Mann-Whitney test was conducted to validate differences between carbon stock in edge and core area. As a result of study, the connectivity analysis was effective to determine forest edge and core. The core and edge of forest patch showed different composition of tree species and soil properties. Carbon stock per tree in the edge area was lower than that in the core area. However, the difference of soil organic carbon content between the edge and core were relatively small. This assessment can be applied for the conservation of forest patch as well as quantitative assessment on the forest carbon stock change caused by fragmentation.