• 제목/요약/키워드: Glow Effect

검색결과 78건 처리시간 0.028초

Chemiluminescence Properties of Polymeric Fluorophores Containing Distyrylarylene Unit

  • 이희우;김철희;공명선
    • Bulletin of the Korean Chemical Society
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    • 제22권7호
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    • pp.727-731
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    • 2001
  • Conjugated-non-conjugated alternating block copolymers containing distyrylarylene units were synthesized via Wittig reaction for chemiluminescent fluorophores. The polymers were differentiated from others by the presence of aromatic unit in the chromophoric block. When UV-VIS, photoluminescence and chemiluminescence spectra of these materials were compared with copolymers, a strong bathochromic effect was observed. A more pronounced red shift and higher chemiluminscence efficiency were observed in the polymer with anthracene ring. Sodium salicylate-catalyzed reaction of bis(2-carbopentyloxy-3,5,6-trichlorophenyl) oxalate with hydrogen peroxide produced a strong chemiluminescence from blue to yellow-green light emission with wavelength of 450-537 nm in the presence of the fluorophore. The chemiluminescent intensity decayed exponentially. The glow of chemiluminescence maintained more than l2 hr and was visible with the naked eye.

Anneal Temperature Effects on Hydrogenated Thin Film Silicon for TFT Applications

  • Ahn, Byeong-Jae;Kim, Do-Young;Yoo, Jin-Su;Junsin Yi
    • Transactions on Electrical and Electronic Materials
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    • 제1권2호
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    • pp.7-11
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    • 2000
  • a-Si:H and poly-Si TFT(thin film transistor) characteristics were investigated using an inverted staggered type TFT. The TFT an as-grown a-Si:H exhibited a low field effect mobility, transconductance, and high gate threshold voltage. The poly-Si films were achieved by using an isothermal and RTA treatment for glow discharge deposited a-Si:H films. The a-Si:H films were cystallized at the various temperature from 600$^{\circ}C$ to 1000$^{\circ}C$. As anneal temperature was elevated, the TFT exhibited increased g$\sub$m/ and reduced V$\sub$ds/. V$\sub$T/. The poly-Si grain boundary passivation with grain boundary trap types and activation energies as a function of anneal temperature. The poly-si TFT showed an improved I$\sub$nm//I$\sub$off/ ratio of 10$\^$6/, reduced gate threshold voltage, and increased field effect mobility by three orders.

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후코이단의 분자량이 화장품기능성에 미치는 영향 (The Effect of Fcoidan Molecula Weight on Cosmetic Function)

  • 차성한;안명원;이정식;김영숙;김동욱;변태강;박권필
    • Korean Chemical Engineering Research
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    • 제50권4호
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    • pp.604-609
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    • 2012
  • 기능성화장품 소재로 사용하기 위한 후코이단의 특성 및 후코이단 분자량의 영향에 대해 연구하였다. 후코이단은 미역 포자엽에서 추출하였고 접촉글로우방전 전기분해(CGDE)방법에 의해 후코이단 분자량(35~160 kDa)을 조절하였다. 후코이단의 tyrosinase inhibition, 보습력, elastase 활성저해 효과와 항산화력(DPPH assay, radical scavenging)을 측정하여 화장품으로서 가능성을 확인하였다. 후코이단의 보습력은 최고의 보습제 중의 하나인 히아루론산의 보습력보다 높았고, 분자량이 감소함에 따라 보습력이 약간 증가하였다. 주름개선 효과실험인 elastase 활성저해 효과 실험결과 표준 비교물질인 adenosine 보다 높은 elastase 활성저해 효과를 보였다. 최고의 tyrosinase 저해효과, elastase 활성저해 효과, 항산화력(DPPH assay, radical scavenging)을 갖는 후코이단의 분자량은 100 kDa이었다.

CVD에 의한 M/NEMS용 다결정 3C-SiC 박막 성장 (Growth of polycrystalline 3C-SiC thin films for M/NEMS applications by CVD)

  • 정귀상;김강산;정준호
    • 센서학회지
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    • 제16권2호
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    • pp.85-90
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    • 2007
  • This paper presents the growth conditions and characteristics of polycrystalline 3C-SiC (silicon carbide) thin films for M/NEMS applications related to harsh environments. The growth of the 3C-SiC thin film on the oxided Si wafers was carried out by APCVD using HMDS (hexamethyildisilane: $Si_{2}(CH_{3})_{6})$ precursor. Each samples were analyzed by XRD (X-ray diffraction), FT-IR (fourier transformation infrared spectroscopy), RHEED (reflection high energy electron diffraction), GDS (glow discharge spectrometer), XPS (X-ray photoelectron spectroscopy), SEM (scanning electron microscope) and TEM (tunneling electro microscope). Moreover, the electrical properties of the grown 3C-SiC thin film were evaluated by Hall effect. From these results, the grown 3C-SiC thin film is very good crystalline quality, surface like mirror and low defect. Therefore, the 3C-SiC thin film is suitable for extreme environment, Bio and RF M/NEMS applications in conjunction with Si fabrication technology.

Plasma polymerization에 의한 PET 직물의 심색화에 관한 연구 (A Study on the Bathochromic of Poly(Ethylene Terephthalate) Fabrics by Plasma Polymerization)

  • 조환;김한기;장병율;이광우;조인술;허만우
    • 한국염색가공학회지
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    • 제5권3호
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    • pp.194-205
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    • 1993
  • Plasma polymerization in prepared glow discharge was carried out to improve the bathochromic of dyed PET fabrics by using silicon containing vinyl monomer in plasma polymerization equipment which consists of a pair of electrodes was connected to the 13.56MHz RF generator. The optimum condition for the bathochromic effect was investigated on various plasma polymeriztion parameters. By plasma polymerization used silicon containing vinyl monomer, the bathochromic of dyed PET fabrics was very enhanced. The optimum conditions on this equipment were as follows ; electrode distance : 3cm, discharge output : 60W, gas pressure : 0.3 Torr, monomer flow rate : 30㎤/min. plasma polymerization time : 60sec. The apparent strength of plasma polymerized PET fabrics was increased about 40∼47% with decreasing about 3 of L value.

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Effects of Oxygen Plasma Treatment on the Wettability of Polypropylene Fabrics

  • Kwon, Young Ah
    • 한국의류산업학회지
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    • 제16권3호
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    • pp.456-461
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    • 2014
  • The objective of this study is to give PP(polypropylene) fabric a good affinity for water. Oxygen plasma was treated to PP fabrics in a commercial glow discharge reactor with different RF power, discharge pressure, and reaction time. The PP fiber surfaces were characterized by the measurement of contact angle and ESCA. A JEOL scanning electron microscope was used to observe the surface morphology of fibers. The spontaneous water uptake amount of PP fabrics was determined by the demand wettability test. To determine the effect of aging on the surface properties of $O_2$ plasma treated PP, all the above measurements of the samples were carried out after 1, 7, 30, 60, and 150 days. The results are as follows. The PP fiber surfaces treated by $O_2$ plasma treatment have a chemical composition that consisted of various oxygen containing polar groups. Consequently, the contact angles of the treated PP fibers decreased, which improved the water uptake rate of PP fabrics. Surface roughness of the treated PP affected the fabric wettabiity as well. Wettability of the treated PP decreased and leveled off with aging. The $O_2$ plasma treatment is a simple and effective method to increase the water uptake rate of PP fabrics.

Preparation and Characterization of PP-g-Poloxamer Membranes by UV Irradiation Methods and their Solutes Permeation Behaviors

  • Lee, S. H.;Shim, J. K.;Lee, Y. M.;Ahn, S. H.;Yoo, I. K.;Baek, K. H.
    • 한국막학회:학술대회논문집
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    • 한국막학회 1998년도 춘계 총회 및 학술발표회
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    • pp.97-98
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    • 1998
  • 1. Introduction : Polypropylene(PP) membrane is widely used in the field of microfiltration and ultrafiltration. However, the hydrophobicity of PP causes the adsorption of hydrophobic and amphoteric solutes in the feed. Surface modification techniques of membrane through the treatment of hydrophilizing agents, coating of hydrophilic compounds, UV, plasma and high energy irradiation, etc. can have a great effect on propensities to prevent the protein from staining membranes. Among them, the modification to hydophilize membrane surface using UV is very simple and effective. Recently many studies for more effective surface modification have been conducted. Iwata et al. prepared membranes by grafting polyethylene glycol diacrylate macromer(PEGDA) onto polysulfone with plasma using a glow discharge reactor which prevent the oil from staining the membrane. The primary mechanism contributing to the membranes is preventing the oil from directly contacting the surface of the membrane as the PEGDA chains dissolved into emulsion. To evaluate their feasibility for use as a anti-fouling separation membrane, we prepared hydrophilic membranes by UV irradiation method and investigated their characteristics.

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불평형 마그네트론 스파터링에 의해 형성된 MgO 박막의 micro 방전에 미치는 bias 전압의 영향에 관한 연구 (Effect of Bias Voltage on the Micro Discharge Characteristic of MgO Thin Film Prepared by Unbalanced Magnetron Sputtering)

  • 김영기;김인성;정주영;조정수;박정후
    • 대한전기학회:학술대회논문집
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    • 대한전기학회 2000년도 하계학술대회 논문집 C
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    • pp.2032-2034
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    • 2000
  • The performance of ac plasma display panels (PDP) is influenced strongly by the surface glow discharge characteristics on the MgO thin films. This paper deals with the surface slew discharge characteristics and some physical properties of MgO thin films prepared by reactive RF planar unbalanced magnetron sputtering in connection with ac PDP. The samples prepared with the do bias voltage of -10V showed lower discharge voltage and lower erosion rate by ion bombardment than those samples prepared by conventional magnetron sputtering or E-beam evaporation. The main factor that improves the discharge characteristics by bias voltage is considered to be due to the morphology changes or crystal structure of the MgO thin film by ion bombardment during deposition process.

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Black Silicon Layer Formation using Radio-Frequency Multi-Hollow Cathode Plasma System and Its Application in Solar Cell

  • U. Gangopadhyay;Kim, Kyung-Hae;S.K. Dhungel;D. Mangalaraj;Park, J.H.;J. Yi
    • Transactions on Electrical and Electronic Materials
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    • 제4권5호
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    • pp.10-14
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    • 2003
  • A low-cost, large area, random, maskless texturing scheme independent of crystal orientation is expected to have significant impact on terrestrial photovoltaic technology. We investigated silicon surface microstructures formed by reactive ion etching (R IE) in Multi-Hollow cathode system. Desirable texturing effect has been achieved when radio-frequency (rf) power of about 20 Watt per one hollow cathode glow is applied for our RF Multi -Hollow cathode system. The black silicon etched surface shows almost zero reflectance in the visible region as well as in near IR region. The etched silicon surface is covered by columnar microstructures with diameters from 50 to 100 nm and depth of about 500 nm. We have successfully achieved 11.7 % efficiency of mono-crystalline silicon solar cell and 10.2 % for multi-crystalline silicon solar cell.

빛공해 분야의 환경영향평가 지침 표준화 연구 (Study on the Standard Guideline of Environmental Impact Assessment Focusing on Light Pollution)

  • 윤희경;최태봉;김부경;김훈
    • 환경영향평가
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    • 제28권1호
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    • pp.63-70
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    • 2019
  • 인공조명은 필수적인 부분이지만, 불필요하거나 과도한 빛의 사용으로 인해 빛공해를 유발시킨다. 빛공해는 전력낭비, 인체의 건강상 악영향, 생태계 파괴 등과 같은 부정적인 영향으로 국 내외에서 법적인 규제를 하고 있다. 하지만 현재는 조명기구 설치 이후의 방법으로만 관리하기 때문에 사전에 빛공해가 유발될 우려가 있는 지역을 효과적으로 관리하고 영향을 저감시키기 위한 빛공해분야 영향평가지침을 제안하고자 한다. 영향평가작성지침을 수립하여 작성자 및 검토자의 혼란을 방지하고 중장기적으로 국내의 빛공해 관리를 효과적으로 수립하는데 활용하고자 한다.