• Title/Summary/Keyword: surface size

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Optical Property and Surface Morphology Control by Randomly Patterned Etching (불규칙 패턴 에칭에 의한 표면 형상 제어와 광학적 특성)

  • Kim, Sung Soo;Lee, Jeong Woo;Jeon, Bup Ju
    • Journal of the Korean Institute of Electrical and Electronic Material Engineers
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    • v.30 no.12
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    • pp.800-805
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    • 2017
  • Randomly patterned and wet chemical etching processes were used to treat anti-glare of display cover glasses. The surface and optical properties of grain size and surface morphology controlled by randomly patterned etching and wet chemical solution etching were investigated. The surface morphology and roughness of the etched samples were examined using a spectrophotometer and a portable surface roughness (Ra) measuring instrument, respectively. The gloss caused by reflection from the glass surface was measured at $60^{\circ}$ using a gloss meter. The surface of the sample etched by the doctor-blade process was more uniform than that obtained from a screen pattern etching process at gel state etching process of the first step. The surface roughness obtained from the randomly patterned etching process depended greatly on the mesh size, which in turn affected the grain size and pattern formation. The surface morphology and gloss obtained by the etching process in the second step depended primarily on the mesh size of the gel state etching process of the first step. In our experimental range, the gloss increased on decreasing the grain size at a lower mesh size for the first step process and for longer reaction times for the second step process.

Quantification of Surface Sites of Ideally Shaped Particles (이상적인 외형을 가진 입자의 표면원자 수계산법)

  • 이수재;김수진
    • Journal of the Mineralogical Society of Korea
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    • v.11 no.2
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    • pp.126-134
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    • 1998
  • Surface site and areas of particles are geometrically calculated for the cubic structures to investigate how the surface sites vary with the variation of morphology and particle size. The numbers of surface site and area become smaller when the particles become equi-dimensional shape. The ratios of surface site to surface area are almost constant except the case of anion of fluorite structure. The ratios of the number of surface site to area are almost constant regardless of particle size except the size of up to 5 to 10 times of the unit cell dimension. This quantification method can be used to obtain data related to the surface reaction.

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Surface Hardness Measurement of Anodic Oxide Films on AA2024 based an Ink-Impregnation Method

  • Moon, Sungmo;Rha, Jong-joo
    • Journal of the Korean institute of surface engineering
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    • v.53 no.2
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    • pp.80-86
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    • 2020
  • This paper is concerned with type of imperfections present within the anodic oxide films on AA2024 and surface hardness of the anodic film measured after ink-impregnation. The anodic oxide films were formed for 25 min at 40 mA/㎠ and 15±0.5℃ and 300 rpm of magnet stirring rate in 20% sulfuric acid solution. The ink-impregnation allows clear observations of not only the imperfections within the anodic oxide films but also an indentation mark on the oxide film surface made by a pyramidal-diamond penetrator for the hardness measurement. There were observed four different regions in the anodic oxide films on AA2024 and the surface hardness of the anodic oxide films appeared to be crucially dependent on the type of defects, showing 60~100 Hv on the oxide surface region I with large size black defect, 100~140 Hv on the oxide surface region II with large size grey defect, 140~170 Hv on the oxide surface region III with mall size black and/or grey defects and 170~190 Hv on the oxide surface region IV without defects. The pyramidal indentation marks were observed to be distorted in the regions with a large size black and grey defects, while no distortion of the indentation mark was observed in the regions with small size defects and without visible defects.

Fine Granulation of Recording Layer in Perpendicular Magnetic Recording Media Using Oxide-interlayer (산화막중간층에 의한 수직자기기록층의 입자크기 미세화)

  • 김경환;공석현
    • Journal of the Korean institute of surface engineering
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    • v.37 no.4
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    • pp.196-199
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    • 2004
  • Seedlayers with low surface energy which increases the density of nucleation sites in the initial growth region of the recording layer deposited on them was studied to reduce grain size in recording layer. The seedlayer with low surface energy was so effective to attain finer grain in magnetic upper-layers. The Ni-Fe-O intermediate layer with low surface energy was found to be effective in reduction of grain size as well as magnetic cluster size of Co-Cr-Ta-Pt recording layer. Furthermore, the reduction of grain size in Co-Cr-Ta-Pt recording layer on Ni-Fe-O intermediate layer with low surface energy led to decrease the noise level in the high recording density region.

Decrease in the Particle Size of Paclitaxel by Increased Surface Area Fractional Precipitation (표면적이 증가된 분별침전에 의한 paclitaxel의 입자 크기 감소)

  • Lee, Ji-Yeon;Kim, Jin-Hyun
    • Microbiology and Biotechnology Letters
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    • v.40 no.2
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    • pp.157-162
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    • 2012
  • In this study, we have for the first time applied increased surface area fractional precipitation in order to decrease the particle size of the anticancer agent paclitaxel from plant cell cultures. When compared with the case where no surface area increasing material was employed, the addition of ion exchange resin as a surface area increasing material resulted in a considerable decrease in the size of the paclitaxel precipitate. When ion exchange resin was used, the paclitaxel particles were four to five times smaller, having less than a 20 ${\mu}m$ radius, than those obtained in the absence of ion exchange resin. This is presumably because the growth of paclitaxel particles was impeded by the addition of ion exchange resin. The size of the paclitaxel precipitate also depended on the material used to increase the surface area, a result considered to be due to differences in the affinity between the particular ion exchange resin used and the paclitaxel particles. The yield of paclitaxel was significantly improved when ion exchange resin was used as a material to increase surface area. Paclitaxel, with a reduced particle size due to the addition of a surface area increasing material during the fractional precipitation process, is believed to be particularly useful for practical applications of the drug.

Study on Size Evaluation by Surface Expansion for Soft Polymer Foam (연질 고분자 발포체의 표면팽창을 통한 치수평가에 관한 연구)

  • Kim, Min-Woo;Cho, Chong-Rae;Kim, Myoung-Hun
    • Journal of the Korean Society of Manufacturing Process Engineers
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    • v.18 no.11
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    • pp.63-68
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    • 2019
  • The dimensional quality of flexible foams is often difficult to be evaluated through general machine vision inspection methods due to the free deformation of the outer shape. For the evaluation of the dimensions of flexible foams, methods of estimating the size of the product through the expansion rate of the product surface are evaluated. Specimens with various dimensions and surface gratings are prepared, and the degree of surface expansion is measured through machine vision. The correlation, between the measured surface grid size and the actual size of test specimens, is analyzed. We further analyze the correlation between the size of test specimens and the position of the surface grid. This study provides a basis for estimating the actual dimensions of specimens by measuring the surface expansion of flexible foams.

Distributions of Mean Particle Size and Age on the Lunar Surface

  • Jung, Min-Sup;Kim, Sung-Soo S.;Min, Kyoung-Wook
    • The Bulletin of The Korean Astronomical Society
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    • v.36 no.2
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    • pp.103.2-103.2
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    • 2011
  • We measure the degree of polarization of the lunar regolith to map the distributions of the age and the particle size. We use a 12cm refracting telescope with a 2k-square pixel color CCD (R band) and a polarization filter. The angular resolution obtained is 3.02 km/pixel. Our goal is to obtain a map of the lunar particle size distribution on the lunar regolith and then that of the age distribution. Polarization of the light scattered by lunar surface contains information on their mean particle size. The mean particle size of the lunar surface has been decreased by continued micro-meteoroid impact over a long period. One can estimate the age of the lunar surface if the mean particle size is known. Particle sizes can be measured through observations of polarization because the mean particle size is related to the maximum polarization and albedo. The age and the particle size of the lunar regolith can give vital information for the future lunar exploration.

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Studies on The Paper Making Technique and TsaiLun (제지술과 채륜에 관한 연구)

  • JongchanLee
    • Journal of the Korean Graphic Arts Communication Society
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    • v.14 no.2
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    • pp.81-99
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    • 1996
  • The characteristics of printing inks are affected, to a greater or lesser extent, by the size and distribution of the pigment particles in the dispersion. Color strength, transparency and gloss increase with a decrease in particle size of pigments and with an increase in surface area of pigments. On the contrary, opacity and lightfastness tend to increases with an increase in particle size of pigments and with a decrease in surface are and particle size if pigments on the physical properties of printing ink which made up vehicles for sheet fed and organic pigment Lake Red C(C.I Pigment Red 53:1) that different surface area and particle size.

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Use of Agar as Surface Sizing Materials in Papermaking (우무를 이용한 종이의 표면사이즈제 개발)

  • Youn, S.K.;Seo, Y.B.
    • Journal of Korea Technical Association of The Pulp and Paper Industry
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    • v.40 no.3
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    • pp.9-14
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    • 2008
  • Agar-agar extracted from red algae was used as a surface sizing material for paper after filtering, bleaching, and viscosity adjustment by oxidative depolymerization. Oxidized starches from corn and tapioca were compared to agar-based surface size in the respects of paper surface modification, strength improvement, and printability. Agar-based surface size showed high strength improvement and good printability as much as starch-based ones except film forming ability, which may be improved by adding additives, and demonstrated its great potential to be used as inexpensive and high quality surface size in future.

Recognition of Road Surface Marks and Numbers Using Connected Component Analysis and Size Normalization (연결 성분 분석과 크기 정규화를 이용한 도로 노면 표시와 숫자 인식)

  • Jung, Min Chul
    • Journal of the Semiconductor & Display Technology
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    • v.21 no.1
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    • pp.22-26
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    • 2022
  • This paper proposes a new method for the recognition of road surface marks and numbers. The proposed method designates a region of interest on the road surface without first detecting a lane. The road surface markings are extracted by location and size using a connection component analysis. Distortion due to the perspective effect is minimized by normalizing the size of the road markings. The road surface marking of the connected component is recognized by matching it with the stored road marking templates. The proposed method is implemented using C language in Raspberry Pi 4 system with a camera module for a real-time image processing. The system was fixedly installed in a moving vehicle, and it recorded a video like a vehicle black box. Each frame of the recorded video was extracted, and then the proposed method was tested. The results show that the proposed method is successful for the recognition of road surface marks and numbers.