• Title/Summary/Keyword: Irregular Shaped

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Initial Growth Mode and Nanostructure of Bulk Heterojunction Layers in Planar Type Metal Pthanlocyanine Molecules

  • Kim, Hyo-Jung;Kima, Ji-Whan;Lee, Hyun-Hwi;Lee, Byeon-Du;Kim, Jang-Joo
    • Proceedings of the Korean Vacuum Society Conference
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    • 2012.08a
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    • pp.162-162
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    • 2012
  • ZnPc and CuPc molecules stacked similar way in the film, but showed different growth modes in thermal evaporation. The distribution of CuPc crystals did not change by the film thickness, whereas the distribution of ZnPc became random as the increase of the film thickness. The disc type nanograins of CuPc were quite regularly distributed at the initial growth regime and the regular distribution of nanograins was kept during the film growth. On the other hand, ZnPc consisted in ellipsoid shaped nanograins and the distribution of nanograins was not regular in the initial growth regime. The irregular distribution of nanograins changed to the regular mode at the later growth regime by showing structure factor in GISAXS measurement. The different initial nanograin distribution in ZnPc and CuPc was related to the different nanostructure in the mixed layer with C60 to form the bulk heterojunction.

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Fabrication of Uniform Hollow Silica Nanospheres using a Cationic Polystyrene Core

  • Yun, Dong-Shin;Jang, Ho-Gyeom;Yoo, Jung-Whan
    • Bulletin of the Korean Chemical Society
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    • v.32 no.5
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    • pp.1534-1538
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    • 2011
  • Uniform, hollow nanosilica spheres were prepared by the chemical coating of cationic polystyrene (cPS) with tetraethylorthosilicate (TEOS), followed by calcination at 600 $^{\circ}C$ under air. cPS was synthesized by surfactant-free emulsion polymerization using 2,2'-azobis (2-methyl propionamidine) dihydrochloride as the cationic initiator, and poly(vinyl pyrrolidone) as a stabilizer. The resulting cPS spheres were 280 nm in diameter, and showed monodispersion. After coating, the hollow silica product was spherically shaped, and 330 nm in diameter, with a narrow distribution of sizes. Dispersion was uniform. Wall thickness was 25 nm, and surface area was 96.4 $m^2/g$, as determined by BET. The uniformity of the wall thickness was strongly dependent upon the cPS surface charge. The effects of TEOS and ammonia concentrations on shape, size, wall thickness, and surface roughness of hollow $SiO_2$ spheres were investigated. We observed that the wall thicknesses of hollow $SiO_2$ spheres increased and that silica size was simultaneously enhanced with increases in TEOS concentrations. When ammonia concentrations were increased, the irregularity of rough surfaces and aggregation of spherical particles were more severe because higher concentrations of ammonia result in faster hydrolysis and condensation of TEOS. These changes caused the silica to grow faster, resulting in hollow $SiO_2$ spheres with irregular, rough surfaces.

Enterobacter cloacae, an Emerging Plant-Pathogenic Bacterium Affecting Chili Pepper Seedlings

  • Garcia-Gonzalez, Tanahiri;Saenz-Hidalgo, Hilda Karina;Silva-Rojas, Hilda Victoria;Morales-Nieto, Carlos;Vancheva, Taca;Koebnik, Ralf;Avila-Quezada, Graciela Dolores
    • The Plant Pathology Journal
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    • v.34 no.1
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    • pp.1-10
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    • 2018
  • A previously unreported bacterial disease on chili pepper (Capsicum annuum L.) seedlings affecting as many as 4% of seedlings was observed in greenhouses in Chihuahua, Mexico (Delicias and Meoqui counties). Initial lesions appeared as irregular small spots on leaves and brown necrosis at margins tips were observed. Later, the spots became necrotic with a chlorotic halo. Advanced disease was associated with defoliation. A Gram negative, rod-shaped bacterium was isolated from diseased chili pepper seedlings. Three inoculation methods revealed that isolated strains produce foliage symptoms, similar to those observed in naturally infected seedlings. Pathogenic strains that caused symptoms in inoculated seedlings were re-isolated and identified to fulfill koch's postulate. Polyphasic approaches for identification including biochemical assays (API 20E and 50CH), carbon source utilization profiling (Biolog) and 16S rDNA, hsp60 and rpoB sequence analysis were done. Enterobacter cloacae was identified as the causal agent of this outbreak on chili pepper seedlings.

Microstructural Features of Multicomponent FeCoCrNiSix Alloys

  • Kong, Kyeong Ho;Kim, Kang Cheol;Kim, Won Tae;Kim, Do Hyang
    • Applied Microscopy
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    • v.45 no.1
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    • pp.32-36
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    • 2015
  • The microstructural features of FeCoCrNi, FeCoCrNiAl and FeCoCrNiSix (x=0, 5, 10, 15, 20) alloys have been investigated in the present study. The microstructure of FeCoCrNi alloy changes dramatically with equiatomic addition of Al. The fcc irregular shaped grain structure in the as-cast FeCoCrNi alloy changes into the bcc interconnected structure with phase separation of Al-Ni rich and Cr-Fe rich phases in the as-cast FeCoCrNiAl alloy. The microstructure of FeCoCrNi alloy changes with the addition of Si. With increasing the amount of Si, the fcc structure of the grains is maintained, but new phase containing higher amount of Si forms at the grain boundary. As the amount of Si increases, the fraction the Si-rich grain boundary phase increases.

Identification and Characterization of Pseudocercospora pyricola Causing Leaf Spots on Aronia melanocarpa

  • Park, Sung-Hee;Choi, In-Young;Seo, Kyoung-Won;Kim, Jin-Ho;Galea, Victor;Shin, Hyeon-Dong
    • Mycobiology
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    • v.45 no.1
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    • pp.39-43
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    • 2017
  • Leaf spot disease on black chokeberry (Aronia melanocarpa) was observed at several locations in Korea during 2014-2015. Leaf spots were distinct, scattered over the leaf surface and along the leaf border, subcircular to irregular and brown surrounded by a distinct dark color, and were expanded and coalesced into irregularly shaped lesions. Severely infected leaves became dry and fell off eventually. The causative agent was identified as Pseudocercospora pyricola. Morphological observations and phylogenetic analyses of multiple genes, including internal transcribed spacer, translation elongation factor 1-alpha, actin, and the large subunit ribosomal DNA were conducted. The pathogenicity test was conducted twice yielding similar results, fulfilling Koch's postulates. To our knowledge, this is the first report on P. pyricola infection of A. melanocarpa globally.

Cluster-Based Spin Images for Characterizing Diffuse Objects in 3D Range Data

  • Lee, Heezin;Oh, Sangyoon
    • Journal of Sensor Science and Technology
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    • v.23 no.6
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    • pp.377-382
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    • 2014
  • Detecting and segmenting diffuse targets in laser ranging data is a critical problem for tactical reconnaissance. In this study, we propose a new method that facilitates the characterization of diffuse irregularly shaped objects using "spin images," i.e., local 2D histograms of laser returns oriented in 3D space, and a clustering process. The proposed "cluster-based spin imaging" method resolves the problem of using standard spin images for diffuse targets and it eliminates much of the computational complexity that characterizes the production of conventional spin images. The direct processing of pre-segmented laser points, including internal points that penetrate through a diffuse object's topmost surfaces, avoids some of the requirements of the approach used at present for spin image generation, while it also greatly reduces the high computational time overheads incurred by searches to find correlated images. We employed 3D airborne range data over forested terrain to demonstrate the effectiveness of this method in discriminating the different geometric structures of individual tree clusters. Our experiments showed that cluster-based spin images have the potential to separate classes in terms of different ages and portions of tree crowns.

A Progressive Automated-Process Planning and Die Design and Working System for Blanking or Piercing and Bending of Sheet Metal Product (박판제품의 블랭킹 및 피어싱과 굽힘 가공을 위한 순차이송용 공정 및 금형 설계와 가공자동화 시스템)

  • Choe, Jae-Chan;Kim, Chul
    • Transactions of Materials Processing
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    • v.7 no.3
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    • pp.246-259
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    • 1998
  • This paper describes a research work of developing a computer-aided design and manufacturing of irregular shaped sheet metal product for blanking or piercing and bending operations. An approach to the system is based on the knowledge-based rules. Knowledge for the system is formulated from plasticity theories experimental results and the empirical knowledge of field experts, This system has been written in AutoLISp on the AutoCAD and in customer tool kit on the SmartCAM with a personal computer and is composed of nine modules which are input and shape treatment, flat pattern-layout, pro-processor module. Based on the knowledge-based rules, the system is designed by considering several factors, such as material and thickness of product complexities of blank geometry and punch profile sheet metal to give flat pattern and automatically account for the adjustment of bending allowances to match tooling requirements by checking dimensions and generating NC data automatically according to drawings of die-layout module. Results carried out in each module will provide efficiencies to the designer and the manufacturer of blanking or piercing and bending die in this field.

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Morphological Analysis of the Dermal Wounds Healing Responses in Bombina orientalis (무당개구리 (Bombina orientalis) 진피 상처치유반응의 형태적 분석)

  • Jeong, Moon-Jin;Moon, Myung-Jin
    • Applied Microscopy
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    • v.28 no.3
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    • pp.379-390
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    • 1998
  • Dermal wound healing responses in the skin of the toad, Bombina orientalis, were examined using transmission electron microscopy. At 12 hours after wounding, debridement and collagenolysis occurred in damaged dermis. Histocyte has a large nucleus and long cytoplasm process. Phagocytic vesicle and lysosome were observed in the cytoplasm. Damaged blood cells were transformed spindle to irregular shape. Autolysis was observed in their cytoplasm. Histocytes are found in poly-band. The irregularly shaped nucleus is located peripheral region in cytoplasm. At 2 days after wounding, partial aggregation of blood cells is observed. Phagocytic, activity is observed in histocyte and collagenolytic collagen fibers are scattered. Fibroblast is observed in the dermis at 3 days after wounding. Clusters of ribosomes and some short cisternae of rough-surfaced endoplasmic reticulum are found in the cytoplasm. In histocyte at 7 days post wounding, various size granules composed of moderately dense material are found the cytoplasm. In this period histocyte is round to rod in profile, with slender processes projecting from the surface. At 7 day after injury, it was observed that formation of connective tissue fibers and amorphous ground substance in regenerating skin.

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A Study of Hair Damage by Magic Straight Perm

  • Lim, Sun-Nye
    • Applied Microscopy
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    • v.42 no.3
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    • pp.129-135
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    • 2012
  • In this study, the changes in hair quality before and after Magic straight perm have been evaluated through a hair damage measurement method. For this, a healthy high school student's (age18 years) wavy hair was selected and permed on the left and right sides. Then, the changes caused by physical methods which were applied during the fl at iron-based Magic straight perm were evaluated based on the hair damage measurement method before and after the Magic straight perm. According to the protein release test after the Magic straight perm, 1.26% in average and 0.14% was observed in Cool Magic straight perm sample. In a field emission scanning electron microscopy (FE-SEM) test, saw teeth-shaped partial desquamation of cuticle cells and impurities were observed in the warm-treated hair sample. In atomic force microscope (AFM), line-profile is a method to represent roughness data on hair. According to analysis on 3-dimensional (3D) images, the hair with Cool Magic straight perm was lower than the hair with Warm Magic perm in terms of the color change of 3D images. In addition, vertical changes were observed in the hair with Cool Magic perm. As a result, irregular surface roughness was observed. This study proposed a method to minimize hair damage by cooling down the heat with the cool hair straightener as soon as the Warm Magic was finished.

Isolation of Actinomycetes Producing Extracellular Adenosin Deaminase (세포외 Adenosine Deaminase를 생산하는 방선균의 분리)

  • 전홍기;김태숙
    • Korean Journal of Microbiology
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    • v.28 no.1
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    • pp.83-89
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    • 1990
  • Two strains of actinomycetes producing extracellular adenosine deaminase, strain J-845S and strain J-326TK, were isolated from soil. Strain J-845S was gram-positive and non-acid-fast. This strain formed whitish, rod-shaped, smooth and non-motile spores on the aerial mycelium, and the spore chain was spiral. The hyphae of the mycelium branched abundantly. Cell wall chemotypes of the strain were of type I containing LL-diaminopimelic acids, and of phospholipid type II, and then strain J-845S was designated as Streptomyces sp.. Strain J-326TK was gram-positive and non-acid-fast. The hyphae of primary and aerial mycelium fragmented into irregular rod of coccus-like elements. The aerial mycelium either did not branch or sparsely branched. Cell wall composition was of type I and phospholipid type I. Thus, strain J-326TK was identified as Nocardioides sp.

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