• 한국수의병리학회지
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• 제5권2호
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• pp.63-66
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• 2001

Two 53-day-old broiler chickens were condemned due to multiple cutaneous nodular masses at slaughter house. Grossly, variable sized round masses were scattered in the abdomen and pelvis. Some of them were large and fused each other. Center of large fused nodules were ulcerated. Histopathologically, tumor masses consisted of multiple cords or masses of epidermal cells. Some of \ulcornerem contained central conoentric lamella of keratin (cancer pearl). From these results, these cases were diagnosed as cutaneous squamous cell carcinoma. This is the first report of cutaneous squamous cell carcinoma occurred in broiler chickens in Korea.

• Journal of Plant Biology
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• 제17권2호
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• pp.95-98
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• 1974

This experiment was undertaken with the purpose of investigating effect of gibberellin on the growth and electron microscopic ultrastructure of hop(Humulus lupulus var. Hallertau) shoot apex. The results are as follows. 1) The growth of stem in the plots treated with GA(10, 25, and 50ppm) is more predominant than control. The leaves and cones of treated plots turn to pale green. 10ppm plot of GA treatment is the most effective in growth and yield than the others. 2) Under the GA-treated condition, it is believed that the nucleoplasmic index (NP) are higher than the control, and so nucleus, nucleolus, mitochondria, primary cell wall, middle lamella, and etc. tends to be larger than the control. 3) Mitochondria contained in the cell of shoot apex treated with concentration of 10ppm GA was seemed to increases in number and be larger in size than the control.

• Journal of Plant Biology
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• 제36권1호
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• pp.97-104
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• 1993

The lipid composition of thylakoid membranes was compared between mesophyll and bundle sheath chloroplasts of maize. According to mild-denaturing gel electrophoresis, mesophyll thylakoids contained both PS I complex and PS II light-harvesting chlorophyll-protein complex(LHCP), while those of bundle sheath cells contained mainly PS I complex. The amount of lipids per mg chlorophyll was higher in bundle sheath thylakoids than in mesophyll. The major polar lipid classes were monogalactosyldiacylglycerol(MGDG), digalactosyldiacylglycreol, sulfolipid and phosphatidylglycerol (PG) in both tissues. Linolenic acid(18 : 3), linoleic acid(18 : 2) and palmitic acid(16 : 0) were the main fatty acyl components, with higher ratio of unsaturated to saturated fatty acids in bundle sheath thylakoids, suggesting these membranes are more fluid. The most striking difference in lipid composition between the two kinds of tissues was the practical absence of trans- 3-hexadecenoic acid(16 : 1t) in PG of bundle sheath thylakoids. This fatty acid is known to be involved in the association of LHCP as oligomeric form. More than 80% of MGDG molecular species was 18 : 3, 18 : 3, demonstrating that maize is a typical 18 : 3 plant. Therefore, the possibility of the functional relationships between the lamella structure, and thus the distribution of photosystems, and MGDG molecular species was excluded.

• Bulletin of the Korean Chemical Society
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• 제33권12호
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• pp.4155-4160
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• 2012

We characterized the physisorption of p-iodo-phenyl octadecyl ether molecules (I-POE) onto superlattice regions of graphite surfaces using scanning tunneling microscopy (STM). The formation of self-organized I-POE monolayers does not affect the overall structures of moir$\acute{e}$ patterns and their modulation periods. However, the packing density of the I-POE monolayer and the orientations of lamella structures were sensitive to the underlying superlattice structure. Depending on the bias voltage, the STM images selectively showed moir$\acute{e}$ pattern, I-POE layer, or both. Reflecting the local density of states at a certain energy level, the STM images thereby revealed the relative energy level scale of the superlattice with respect to the molecular orbitals of I-POE.

• Bulletin of the Korean Chemical Society
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• 제34권5호
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• pp.1388-1390
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• 2013

Macroporous $SnO_2$ foam was successfully synthesized via a simple soft-chemical route by hybridization between alkylamine and tin(IV) oxide. According to X-ray diffraction (XRD) analysis, the as-prepared $SnO_2$ foam had a highly ordered lamella structure along the crystallographic c-axis, which transformed to a rutile phase after thermal treatment at $300^{\circ}C$. X-ray absorption spectroscopy (XAS) at the Sn K-edge revealed that $SnO_2$ particles in the hybrid material maintained their nanosized structure after hybridization with alkylamine. Scanning electron microscope (SEM) images clearly showed that the as-prepared $SnO_2$ foam had a macroporous structure. This synthetic route can be extended to the development of open frameworks with good electrochemical properties in battery applications.

• Journal of Magnetics
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• 제20권2호
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• pp.138-147
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• 2015

The unique nano-scale inter-lamellar microstructure and unparalleled heat treatment process give our developed metal powder composite its outstanding magnetic property for power inductor & motor applications. Compared to the conventional polycrystalline Fe or amorphous Fe-Cr-Si-B alloys, our unique designed inter-lamellar microstructure strongly decreases the intra-particle eddy current loss at high frequencies by blocking the mutual eddy currents. The combination of optimum permeability, magnetic flux and extremely low core loss makes this powder composite suitable for high frequency applications well above 10 MHz. Moreover, it can be also possible to SMC core for high speed motor applications in order to increase the motor efficiency by decreasing the core loss.

• Applied Microscopy
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• 제28권4호
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• pp.513-525
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• 1998

The spermatogenetic process in the edible giant snail is similar to those in the other snails, except for the axoneme formation process. In this study, the axoneme formation process in the giant snail was mainly examined by means of electron microscopy. The tail portion of a spermatozoon is about $160{\mu}m$ long, and extends straight to the rear, surrounded by two large and long mitochondria in spiral forms. A number of glycogen particles $(40\sim70nm)$ are found in the swollen matrix of the mitochodria. The axoneme which composes the tail of a spermatozoon is surrounded by $7\sim10$ lamella-form fibrous sheaths of about $0.2{\mu}m$ in thickness. Most of the mature spermatozoa are found to be clustered into a group of $5\sim7$ ea in syncytial bridges formed by cytoplasmic processes. Sertoli cells contain glycogen particles, endoplasmic reticulum, a lot of mitochondria, and lipids in their cytoplasm. They protrude their filiform pseudopodia and phagocytize abnormal spermatids or spermaozoa.

• Journal of Industrial and Engineering Chemistry
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• 제68권
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• pp.24-32
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• 2018

Nanocellulose was surface-functionalized toward the applications in enhanced oil recovery (EOR) as a green alternative. The focus of this paper is on the effect of this material based nanofluid (NF) on foam lamella stabilization through studying its bubble breakup dynamics and flow behaviors in constricted mircofluidic devices. The NF stabilized foam produced an improved flow resistance across the capillary largely due to the capillary trapped bubbles at the contraction. The "snap-off" caused the NF stabilized foam to produce finer textured bubbles, which can migrate readily forward to the deep porous media, as revealed by the pressure profiles.

• 소성∙가공
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• 제27권6호
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• pp.379-385
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• 2018

This study investigated the effect of extrusion conditions on microstructures and mechanical properties of AM80 magnesium alloys. The billets of magnesium alloy used for hot extrusion were prepared by permanent mold casting method, and its extrusion was hot direct extrusion with different extrusion conditions. The results of microstructural analysis showed that the main phases in the as-casted alloys were ${\alpha}-Mg$, ${\beta}-Mg_{17}Al_{12}$, and lamella $Mg_{17}Al_{12}$. Hot extrusion results, The tensile strength of the most soundly manufactured extruded bars (extrusion temp: $350^{\circ}C$, extrusion ratio: 27:1, ram speed: 2mm/s) was approximately 327MPa at room temperature. The increase in the mechanical properties of hot-extruded alloys was as a result of grain refinement by dynamical recrystallization during hot extrusion.

• Journal of Species Research
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• 제11권2호
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• pp.94-97
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• 2022

Linyphiidae Blackwall, 1859 is one of the most diverse and largest families within the order Araneae Clerck, 1757. Of the currently 60 valid species of the genus Neriene Blackwall, 1833 worldwide, 10 species are distributed in Korea. The males of the new sheet-web spider Neriene bovista sp. nov. were recently collected with a sweep net between the shrubs of mixed forests from the hilly valley with well conserved nature in Uljin-gun, Gyeongsangbuk-do (the middle east coast region) during a seasonal survey of the spider fauna in hilly terrains in 2017-2018. The present study describes a new sheet-web spider, Neriene bovista sp. nov. with a diagnosis, detailed description, morphological illustrations, and a distribution map from Korea. The new species has a characteristic mushroom-like tip of the terminal apophysis, the truncated tip of anterior projection, and the bifurcated lateral projection of the lamella compared to the congeners of the genus Neriene Blackwall, 1833.