• Title/Summary/Keyword: morphological and structural characteristics

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Effect of Vibration on Trabecualr Bone of OVX Rats (기계적 자극이 난소 제거한 쥐 해면골에 미치는 영향 분석)

  • Ko C.Y.;Lee T.W.;Woo D.G.;Kim H.S.;Kim C.H.;Lee B.Y.
    • Proceedings of the Korean Society of Precision Engineering Conference
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    • 2006.05a
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    • pp.649-650
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    • 2006
  • Some researchers proposed positive effects of whole body vibration (WBV) on osteoporotic trabecular bones of animals. In the present study, the correlation between the improvement of morphological characteristics and the effect of WBV was investigated and analyzed in OVX rats. The rats were randomly assigned to 5 groups: control, sham, WBV 17Hz, WBV 30Hz and WBV 45Hz. The WBV groups were exercised on a vibration platform (magnitude $1mm_{peak-peak}$, frequency : 17Hz, 30Hz and 45Hz, 30 minutes/day for 5 days/week). The 4th lumbar on rats was scanned by In-vivo Micro-CT at the week 0(iust before WBV) and the week 8(after WBV). Structural parameters of the 4th lumbar, based on two dimensional (2D) scan image data, were investigated and analyzed. The quantitative decrement rate of trabecular bone on WBV groups with 30Hz and 45Hz were lower than control and sham groups. The results showed the positive effect of WBV on osteoporotic bones of OVX rats.

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Characteristics of ZnO Thin Films Grown on p-type Si and Sapphire Substrate by Pulsed Laser Deposition

  • Lee, K. C.;Lee, Cheon
    • KIEE International Transactions on Electrophysics and Applications
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    • v.3C no.6
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    • pp.241-245
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    • 2003
  • ZnO thin films on (l00) p-type Si and sapphire substrates have been deposited by a pulsed laser deposition technique using an Nd:YAG laser with a wavelength of 266 nm. The influence of the deposition parameters such as oxygen pressure, substrate temperature and laser energy density on the properties of the grown films was studied. The experiments were performed for substrate temperatures in the range of 200∼50$0^{\circ}C$ and oxygen pressure in the range of 100∼700 sccm. All of the films grown in this experiment show strong c-axis orientation with (002) textured ZnO peak. With increasing substrate temperature, the FWHM (full width at half maximum) and surface roughness were decreased. In the case of using sapphire substrate, the intensity of PL spectra increased with increasing ambient oxygen flow rate. We investigated the structural and morphological properties of ZnO thin films using X-ray diffraction (XRD), scanning electron microscopy (SEM) and atomic force microscopy (AFM).

Structure and Form Derived from Folding; from Pleated Shape to Deployable Structure (폴딩을 이용한 구조와 형태)

  • Park, Sun-Woo;Choi, Sun-Young;Choi, Chui-Kyung
    • Journal of Korean Association for Spatial Structures
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    • v.7 no.2 s.24
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    • pp.45-52
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    • 2007
  • The purpose of this study is to explore folding as a tool diversifying structures and shapes or forms, and to consider the role and possibilities as structural design sources. First, the morphological characteristics and the elements for transforming pattern of folding are investigated and the way of forming space is also shown. Secondly, the application methods and systems of folding are descrived.

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Graphite상의 ZnO Nanorod성장과 그를 이용한 Schottky Diode 제작

  • Nam, Gwang-Hui;Baek, Seong-Ho;Park, Il-Gyu
    • Proceedings of the Korean Vacuum Society Conference
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    • 2014.02a
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    • pp.421.2-421.2
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    • 2014
  • We report on the growth of ZnO nanorods (NRs) grown on graphite and silicon substrates via an all-solution process and characteristics of their heterojunctions. Structural investigations indicated that morphological and crystalline properties were not significantly different for the ZnO NRs on both substrates. However, optical properties from photoluminescence spectra showed that the ZnO NRs on graphite substrate contained more point defects than that on Si substrate. The ZnO NRs on both substrates showed typical rectification properties exhibiting successful diode formation. The heterojunction between the ZnO NRs and the graphite substrate showed a Schottky diode characteristic and photoresponse under ultraviolet illumination at a small reverse bias of -0.1 V. The results showed that the graphite substrate could be a good candidate for a Schottky contact electrode as well as a conducting substrate for electronic and optoelectronic applications of ZnO NRs.

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Characteristics and Preparation of CNT:ZnO Gas Sensors (CNT:ZnO 가스 센서의 제조와 특성 연구)

  • Yoon, So-Jin;Yu, Il
    • Journal of the Korean Institute of Electrical and Electronic Material Engineers
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    • v.27 no.7
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    • pp.468-471
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    • 2014
  • The effects of ZnO coating on the sensing properties of CNT:ZnO based gas sensors were studied for $H_2S$ gas. The nano ZnO sensing materials were grown by hydrothermal reaction method. CNT:ZnO was prepared by ball-mill method. The mole range of nano ZnO coating on CNT surface was from 0 to 10%. The CNT:ZnO gas sensors were fabricated by a screen printing method on alumina substrates. The structural and morphological properties of the CNT:ZnO sensing materials were investigated by XRD, EDS, SEM and TEM. The XRD patterns showed that CNT:ZnO powders with hexagonal structure were grown with (002) dominant peak. The diameter of CNT from TEM was about 28 nm.

Photoluminescence characteristics of ZnO thin films by Pulsed laser deposition (PLD를 이용한 ZnO 박막의 발광에 관한 연구)

  • Kim, Jae-Hong;Lee, Kyoung-Cheol;Lee, Cheon
    • Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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    • 2002.07b
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    • pp.1030-1033
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    • 2002
  • ZnO thin films on (100)p-type silicon substrates have been deposited by pulsed laser deposition(PLD) technique using an Nd:YGA laser with a wavelength of 266nm. The influence of the deposition parameters, such as oxygen pressure, substrate temperature and laser energy density variation on the properties of the grown film, was studied. The experiments were performed for substrate temperatures in the range of $200{\sim}500^{\circ}C$ and oxygen pressure in the range of $10^{-2}{\sim}10^2mTorr$. We investigated the structural, morphological and optical properties of ZnO thin films using X-ray diffraction(XRD), atomic force microscopy(AFM), photoluminescence(PL).

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The Surface Analysis of the Merocyanine Dye LB film using Optical system (광학시스템을 이용한 메로시아닌 색소 LB막의 표면 모폴로지 해석)

  • Kang, Ki-Ho;Shin, Hoon-Kyu;Chang, Jung-Soo;Kwon, Young-Soo
    • Proceedings of the KIEE Conference
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    • 2000.07c
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    • pp.1714-1716
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    • 2000
  • We fabricated the optical system of merocyanine dye using Langmuir-Blodgett(LB) technique because quite uniform orientation could be obtained, which is one of the most important factors to affect to its optical characteristics. The resonance frequency and other electrical parameters at the parallel resonance state were measured using the impedance analyser(HP 4294 A). Also the morphological changes of dye molecules after UV irradiation were observed using AFM. The parallel resonance frequency and resistance by electrical equivalent circuit were decreased with the UV irradiation and these aspects are different from general mass adsorption process. Therefore the structural changes of dye molecules are being considered, that is, the aggregated molecules become dissociated. It indicates that the shifts of the resonance frequency and the others occurred without mass absorption.

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Fine Structure of the Cutaneous Pigments in the Black Widow Spider, Latrodectus mactans (검은과부거미 (Latrodectus mactans) 피부 색소의 미세구조에 관한 연구)

  • Moon, Myung-Jin
    • Applied Microscopy
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    • v.28 no.4
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    • pp.503-512
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    • 1998
  • Fine structure of the cutaneous pigments in the black widow spider, Latrodectus mactans are studied with light and electron microscopes. The cutaneous pigments are only observed in epidermal layer just beneath the cuticle. These pigments are compactly distributed around the spinnerets which located at caudal area of the abdomen. According to the fine structural characteristics of the pigment granules, two main types of guanine pigment granules-carotenoid vesicles and reflecting platelets - are observed in the cytoplasm of the epidermal cells. Morphological features of these pigment granules are characterized as the electron dense carotenoid vesicles and the electron lucent reflecting platelets. Marginal electron density of the carotenoid vesicle is different from that of internal region, whereas the reflecting platelets have laminated crystalline granules. Typiral structures of these pigment granules are very similar to those of invertebrate's chromatophores, especially erythrophores and iridophores. Moreover differentiation of these pigment granules are also originated from the small vesicles of Golgi complexes similarly to those of cutaneous chromatophores.

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Instrumental Analysis of the Human Hair Damaged by Bleaching Treatments - Focused on ATR FT-IRM -

  • Ha, Byung-Jo
    • Journal of Fashion Business
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    • v.12 no.6
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    • pp.23-33
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    • 2008
  • The physico-chemical characteristics by bleaching treatments were assessed by several instrumental analyses such as surface morphology, chemical structural change, color change as well as tensile strength. The change of morphological characteristic was observed through scanning electron microscope(SEM). The observation of the fine structure on hair surface by SEM showed the bleached hair had much damaged to hair cuticle, and some of cuticle surface were worn away. To investigate the chemical structural changes in hair keratin, the cross-sections of hair samples were directly analysed using Fourier transform infrared microspectroscopy(FT-IRM). The results showed the cysteic acid S=O band intensity was distinctively increased by performing the bleaching treatment. The cleavage of cystine was appeared to proceed primarily through the sulfur-sulfur (-S-S-) fission whereby cysteic acid was formed as a principal oxidation products. The distribution of amide I band in hair keratin was determined by attenuated total reflectance(ATR) FT-IR mapping image. The results showed that the outer side of hair cortex was more damaged than the inner side of the hair cortex. Also, during chemical bleaching of the hair with alkaline peroxide, the hair was turned to reddish yellow due to the oxidative degradation of eumelanin. This means the eumelanin is more unstable than pheomelanin in chemical oxidation. With bleaching, the tensile strength was also reduced as a results of the chemical oxidation.

Characteristics of organic design in Alexander McQueen's collections (알렉산더 맥퀸 컬렉션에 나타난 유기적 디자인 특성)

  • Kim, Dana;Lee, Younhee
    • The Research Journal of the Costume Culture
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    • v.30 no.2
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    • pp.262-280
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    • 2022
  • The purpose of this study is to analyze the organic forms, expressions, and characteristics of Alexander McQueen's fashion design and to present various materials for understanding and utilizing this organic design style. The criteria for organic design expressions and characteristics were classified through a literature review, and the organic design characteristics of Alexander McQueen's fashion were then analyzed. The results are as follows: First, the morphological characteristics of nature's forms are used as objects in Alexander McQueen's fashions to represent organic characteristics. Second, abstraction through the application of organic forms means creating an abstract representation of the object being represented. Abstracting organic forms occurs by partially modifying the structural features of the human body to show characteristics or by visualizing these characteristics within the surface of the natural object. Third, continuity through the expression of the formation process of organisms is characteristic of the expression of the gradual growth of organisms; this reinterpretation is based on the concept that the internal elements of natural objects affect their external forms. Fourth, the structure of using natural materials, as well as regional and cultural characteristics, is shown in the designs through use of the physical characteristics of expressions and materials that use natural elements. Fifth, symbolism through subjective thinking implies that the element of nature that an object expresses is the element that appears in nature; this includes created organisms along with environmental factors. These characteristics are best demonstrated in fashion designs that express themselves through creativity.