• Title/Summary/Keyword: SEM (scanning electron microscope)

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Electrical and Resistance Heating Properties of Carbon Fiber Heating Element for Car Seat (자동차 시트용 탄소섬유 발열체의 전기적 및 저항 발열 특성)

  • Choi, Kyeong-Eun;Park, Chan-Hee;Seo, Min-Kang
    • Applied Chemistry for Engineering
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    • v.27 no.2
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    • pp.210-216
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    • 2016
  • In this paper, the electrical and resistance heating properties of carbon fiber heating elements with different electroless Ni-P plating times for car seat were studied. The specific resistance and specific heat of the carbon fibers were determined using 4-point probe method and differential scanning calorimetry (DSC), respectively. The surface morphology and temperature of carbon fibers were measured by scanning electron microscope (SEM) and thermo-graphic camera, respectively. From experimental results, the nickel layer thickness and surface temperature of carbon fibers increased with increasing the plating time. However, the specific heat and specific resistance decreased with respect to the increased plating time. In conclusion, the electroless Ni-P plating could improve the resistance heating and electrical properties of carbon fiber heating elements for car seat.

Physicochemical Properties of Starches from Flavored Glutinous Rice Varieties (향미찹쌀전분의 이화학적 특성비교)

  • 최영희;김광호;강미영
    • Journal of the Korean Society of Food Science and Nutrition
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    • v.30 no.5
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    • pp.765-769
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    • 2001
  • Starches of flavored glutinous rice were analyzed by using scanning electron microscope (SEM) and differential scanning calorimetry (DSC) and tested on the starch granule susceptibility to 15% H$_2$SO$_4$, glucoamylase and $\alpha$-amylase. The shape of starch granules form flavored glutinous rice varieties was polygonal and the size was 4~6 $\mu$m in diameter. According to DSC, glutinous rice starch showed onset temperature (T$_{o}$) range 59.8~62.5$^{\circ}C$ and KR92021-B-B-42-3-B and KR92021-B-B-165-1-B showed higher enthalpy ($\Delta$H) on gelatinization than others. The starches from KR92021-B-B-5-2-B and KR92021-B-B-42-3-B showed lower hydrolysis rate using 15% H$_2$SO$_4$ than KR92021-B-B-165-1-B. KR92021-B-B-5-2-B showed higher degree of hydrolysis of glucoamylase and $\alpha$-amylase than the others.

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Thickness Measurement of Ni Thin Film Using Dispersion Characteristics of a Surface Acoustic Wave (표면파의 분산 특성을 이용한 Ni 박막의 두께 측정)

  • Park, Tae-Sung;Kwak, Dong-Ryul;Park, Ik-Keun;Kim, Miso;Lee, Seung-Seok
    • Journal of the Korean Society for Nondestructive Testing
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    • v.34 no.2
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    • pp.171-175
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    • 2014
  • In this study, we suggest a method to measure the thickness of thin films nondestructively using the dispersion characteristics of a surface acoustic wave propagating along the thin film surface. To measure the thickness of thin films, we deposited thin films with different thicknesses on a Si (100) wafer substrate by controlling the deposit time using the E-beam evaporation method. The thickness of the thin films was measured using a scanning electron microscope. Subsequently, the surface wave velocity of the thin films with different thicknesses was measured using the V(z) curve method of scanning acoustic microscopy. The correlation between the measured thickness and surface acoustic wave velocity was verified. The wave velocity of the film decreased as the film thickness increased. Therefore, thin film thickness can be determined by measuring the dispersion characteristics of the surface acoustic wave velocity.

Investigation of Micromorphological Characteristics of Acupuncture Needle Tip Using SEM in Korea(2) (주사전자현미경(SEM)을 이용한 일회용침 끝의 미세 형태에 대한 관찰(2))

  • Jang, In-soo;Park, Jong-bae;Song, Beom-yong;Lee, Chang-hyun;Kim, Hyun-soo
    • Journal of Acupuncture Research
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    • v.20 no.5
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    • pp.151-158
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    • 2003
  • Objective: There have not been so many study about the quality of acupuncture needle tip. In order to ensure safe acupuncture treatment, the quality of needle tip is essential. Therefore we investigated the current condition of the tip of the acupuncture needles in Korea. Methods: We have selected the needles that made by 8 companies in Korea, and selected 50 pieces from 1000 pieces each company by randomized methods. and observed the tip of each needle using a scanning electron microscope at ${\times}800$ magnification. Results & Discussion: We found that needles had several defects such as scratch marks on the surface, metallic scuff, lumps and irregularities of the needle tips, stubbed or malformed tips, tips of point off-center, peeled off coated tips. There was much difference on the quality of needle among the manufacturer, and some needles seem to need to do- thorough quality control. It is necessary to intensify quality management and a concentrated control on manufacturing process of acupuncture needles.

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Novel Encapsulation with New Glyceryl Ester Vesicle Enhances Stability of Nanoemulsion Containing Astaxanthin (아스타잔틴을 포함하는 나노에멀젼의 안정성 향상을 위한 신규 Glyceryl Ester 이용 캡슐화)

  • Kim, Dong Myung;Hong, Weon Ki;Kong, Soo Sung;Lee, Un Yep
    • Journal of the Society of Cosmetic Scientists of Korea
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    • v.39 no.3
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    • pp.225-231
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    • 2013
  • Oil in water nanoemulsion of astaxanthin was prepared by high pressure homogenization. The emulsifying conditions including emulsifier type, concentration and astaxanthin concentration were optimized. Stability of nanoemulsion was measured using zetasizer, freeze-fracture scanning electron microscope (FF-SEM), particle analyzer and colorimeter. The mean diameter of the dispersed particles containing astaxanthin ranged from 160 to 190 nm. Size distribution was unimodal and extended from 40 to 200 nm. The nanoemulsion prepared by glyceryl citrate/lactate/linoleate/oleate had smaller particle size and narrow size distribution. Stable incorporation of astaxanthin in nanoemulsion was performed and checked using high performance liquid chromatography (HPLC), freeze-fracture scanning electron microscope (FF-SEM). Physical stability of nanoemulsion was not significantly changed during storage at both light and thermal condition for a month with zeta potential value of -41 mV meaning stable colloid.

Synthesis of CuO nanoparticles by liquid phase precursor process (액상프리커서법에 의한 산화구리(CuO) 나노 입자의 합성)

  • Seong-Whan Shinn
    • The Journal of the Convergence on Culture Technology
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    • v.9 no.6
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    • pp.855-859
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    • 2023
  • Copper oxide (CuO) nanoparticles were successfully synthesized using a precursor in which industrial starch was impregnated with an aqueous solution of copper (II) nitrate trihydrate. The microstructure of the precursor impregnated with an aqueous solution of copper nitrate trihydrate was confirmed with a scanning electron microscope (SEM), and the particle size and the crystal structure of the copper oxide particles produced as the temperature of the heat treatment of the precursor increased was analyzed by X-ray diffraction (XRD) and the scanning electron microscope (SEM). As a result of the analysis, it was confirmed that the temperature at which the organic matter of the precursor is completely thermally decomposed is 450-490℃, and that the size and crystallinity of the copper oxide particles increased as the heat treatment temperature increased. The size of the copper oxide particles obtained through heat treatment at 500-800℃ during 1 hour was 100nm~2㎛. It was confirmed that the copper oxide crystalline phase is formed at a heat treatment temperature of 400℃, and only the copper oxide single phase existed up to 800℃. And it was also confirmed that the size of particles produced increased as the calcination temperature increased.

Nano-structural Characteristics of N-doped ZnO Thin Films (N-doped ZnO 박막의 미세 구조 특성)

  • Lee, Eun-Ju;Zhang, Ruirui;Park, Jae-Don;Yoon, Gi-Wan
    • Journal of the Korea Institute of Information and Communication Engineering
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    • v.13 no.11
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    • pp.2385-2390
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    • 2009
  • N-doped ZnO thin films with c-axis preferred orientation were prepared on p-Si(100) wafers, using an RF magnetron sputter deposition. For ZnO deposition, $N_2O$ gas was employed as a dopant source and various deposition conditions such as $N_2O$ gas fraction and RF power were applied. The depth pofiles of the nitrogen [N] atoms incorporated into the ZnO thin films were investigated by Auger Electron Spectroscopy(AES) and the nano-scale structural characteristics of the N-doped ZnO thin films were also investigated by a scanning electron microscope (SEM) technique.

Measuring the Tensile Properties of the Nanostructure Using a Force Sensor (힘센서를 이용한 나노구조체의 인장물성 측정)

  • Jeon, Sang-Gu;Jang, Hoon-Sik;Kwon, Oh-Heon;Nahm, Seung-Hoon
    • Transactions of the Korean Society of Mechanical Engineers A
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    • v.34 no.2
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    • pp.211-217
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    • 2010
  • It is important to measure the mechanical properties of nanostructures because they are required to determine the lifetime and reliability of nanodevices developed for various fields. In this study, tensile tests for a multi-walled carbon nanotube (MWCNT) and a ZnO nanorod were performed in a scanning electron microscope (SEM). The force sensor was a cantilever type and was mounted in front of a nanomanipulator placed in the chamber. The nanomanipulator was controlled using a joystick and personal computer. The nanostructures dispersed on the cut area of a transmission electron microscope (TEM) grid were gripped with the force sensor by exposing an electron beam in the SEM; the tensile tests were the performed. The in situ tensile loads of the nanostructure were obtained. After the tensile test, the cross-sectional areas of the nanostructures were observed by TEM and SEM. Based on the TEM and SEM results, the elastic modulus of the MWCNT and ZnO nanorod were calculated to be 0.98 TPa and 55.85 GPa, respectively.

Studies on the Protoplast Formation of Cellulomonas flavigena and its Observations under Scanning Electron Microscope (Cellulomonas flarigena의 원형질체 형성과 주사전자현미경적 연구)

  • Bae, Moo;Lee, Eun-Ju
    • Microbiology and Biotechnology Letters
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    • v.14 no.2
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    • pp.175-179
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    • 1986
  • In order to develope a protoplast fusion of the genus Cellulomonas having high assimilibility of cellulose, the optimum conditions for the protoplast formation of Cellulomonas flavigena NCIB 12901 was investigated and observed by means of Scanning Electron Microscope. The results suggested that the susceptibility of the cell wall by lysozyme treatment on protoplast formation was considerably depend on the cultural periods of the cells. Cells of C. flavigena at mid exponential phase could more efficiently convert to protoplast cells than those at late exponential phase did. The rate of the protoplast formation was 95%, even though the rate was over 99.9% on counting by indirect method after osmotic shock treatment, when cells of the organism at mid exponential phase were treated with lysozyme (400$\mu\textrm{g}$/$m{\ell}$) for 6 hours and observed by SEM. In the evaluation of protoplast formation of the genus Cellulomonas, direct method of the observation under Scanning Electron Microscope was much more reliable than the counting method of protplasts after osmotic shock treatment. Because defferences between the number of spheroplast and protoplast were not able to be figured out on counting the number of protoplast after osmotic shock treatment.

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The Effect of Magnetic Field Direction on the Imaging Quality of Scanning Electron Microscope

  • Ai, Libo;Bao, Shengxiang;Hu, Yongda;Wang, Xueke;Luo, Chuan
    • Journal of Magnetics
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    • v.22 no.1
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    • pp.49-54
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    • 2017
  • The significant reduction of the image quality caused by the magnetic field of samples is a major problem affecting the application of SEM (scanning electron microscopy) in the analysis of electronic devices. The main reason for this is that the electron trajectory is deflected by the Lorentz force. The usual solution to this problem is degaussing the sample at high temperatures. However, due to the poor heat resistance of some electronic components, it is imperative to find a method that can reduce the impact of magnetic field on the image quality and is straightforward and easy to operate without destroying the sample. In this paper, the influence of different magnetic field directions on the imaging quality was discussed by combining the experiment and software simulation. The principle of the method was studied, and the best observation direction was obtained.