• 제목/요약/키워드: Irradiation intensity

검색결과 442건 처리시간 0.028초

이온빔을 이용한 폴리이미드 표면의 액정배향효과 (Liquid Crystal Alignment Effect on Polyimide Surface by Ion-beam Irradiation)

  • 박홍규;오병윤;김영환;김병용;한정민;서대식
    • 한국전기전자재료학회:학술대회논문집
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    • 한국전기전자재료학회 2008년도 추계학술대회 논문집 Vol.21
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    • pp.330-330
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    • 2008
  • It is widely investigated to liquid crystal (LC) alignment using non-contact alignment method such as ion-beam (IB) irradiation, UV alignment, and oblique deposition. Because conventional rubbing method has some drawbacks. These include defects from dust and electrostatic charges and rubbing scratch during rubbing process. In addition, rubbing method needs additional process to remove these defects. Therefore rubbing-free methods like ion-beam irradiation are strongly required. We studied LC alignment effect on poly imide surface by IB irradiation and electro-optical (EO) characteristics of twisted nematic liquid crystal display (TN-LCD). In this experiment, a good uniform alignment of the nematic liquid crystal (NLC) with the ion-beam exposure on the polyimide (PI) (SE-150 from Nissan Chemical) surface was observed. We also achieved low pretilt angle as a function of ion-beam irradiation intensity. In addition, it can be obtained the good EO properties of the IB-aligned TN-LCD on PI surface. Some other experiments results and discussion will be included in the poster.

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감마선 조사된 알로에 베라의 PSL, TL 및 ESR 검지 특성 (Detection Characteristics of Irradiated Aloe vera by the Analysis of PSL, TL and ESR)

  • 김병근;임상용;송현파;윤혜정;권중호;김동호
    • 한국식품저장유통학회지
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    • 제13권1호
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    • pp.61-65
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    • 2006
  • 알로에 베라(Aloe barbadensis Miller)분말에 대한 방사선 조사 여부를 확인하기 위해 1, 3, 5, 7 kGy로 감마선 조사를 실시하여 PSL, TL 및 ESR 분석을 실시하였다. PSL의 경우 비조사 시료에서는 700이하의 photon count를 나타내었으며, 1 kGy이상 조사된 시료에서는 5000이상의 photon count를 나타내어 PSL을 통한 조사된 알로에 분말의 검지가 가능할 것으로 사료된다. TL분석 결과에서는 1 kGy이상 조사된 시료의 미네랄에서 $150^{\circ}C$ 전후에 TL glow curve $(TL_1)$를 확인할 수 있었고, 조사선량이 증가함에 따라 $TL_1$ 및 TL ratio $(TL_1/TL_2)$모두 증가 경향을 나타내었다. 한편 전자스핀공명 (ESR)분석 결과에서는 triplet형태의 ESR signal은 확인 할 수 없었으나, 조사전량이 증가함에 따라 signal의 크기가 증가하였다. 본 연구결과 PSL, TL 및 ESR분석으로 알로에 베라 분말의 조사여부를 확인할 수 있었으며 특히, IL분석으로는 조사선량의 정량적 예측이 가능할 것으로 사료되었다.

건포도와 건바나나의 감마선 조사와 저장기간에 따른 열발광 및 전자스핀공명 특성과 관능적 품질 (Characteristics of Thermoluminescence and Electron Spin Resonance and Organoleptic Quality of Irradiated Raisin and Dried Banana During Storage)

  • 조덕조;권중호
    • 한국식품영양과학회지
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    • 제31권4호
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    • pp.609-614
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    • 2002
  • 방사선 조사(1~4 kGy)와 저장 기간(4$^{\circ}C$, 6개월)에 따른 건조과일의 TL 및 ESR검지 특성과 관능적 품질을 평가하였다. 건포도에서 분리된 mineral의 TL측정에서 비조사구는 200~30$0^{\circ}C$ 부근에서 매우 낮은 intensity의 glow curve(TLI)를 나타내었으나, 1 kGy 이상의 조사구에서는 특유의 peak가 18$0^{\circ}C$ 부근에서 나타나면서 선량 의존적으로 intensity가 증가되었다($R^2$=0.9684). 이로써 방사선 조사구와 비조사구의 판별이 6개월 동안 가능하였다. 또한 재조사(1 kG)에 의해 측정된 TL$_2$signal을 활용하여 TL ratio(TL$_1$/TL$_2$)를 계산하였을 때 검지결과의 신뢰도를 높일 수 있었다. 건 바나나의 ESR 측정에서 1 kGy 이상의 조사 시료는 crystalline sugar radical 유래의 전형적인 multicomponent line을 보여 주어 조사 여부의 판별이 가능하였고 signal의 강도는 선량 의존적($R^2$= 0.8977)으로 6개월 동안 비교적 안정하였다. 방사선 조사된 건조과일은 6개월까지 상품성이 잘 유지되었으므로 TL 및 ESR 분석은 건포도와 건 바나나의 검지 관리에 적합한 방법임이 확인되었다.

동물 세포 증식을 위한 저출력 광 소스의 특성 (Characteristics of Low-level Light Source for Animal Cell Proliferation)

  • 천민우;김성환;송창훈;문성표;김태곤;박용필;김대영;김영수
    • 한국전기전자재료학회논문지
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    • 제20권1호
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    • pp.92-97
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    • 2007
  • This paper performed the basic study for developing the Photodynamic Therapy Equipment for medical treatment. We developed the equipment palpating cell proliferation using a high brightness LED. This equipment was fabricated using a micro-controller and a high brightness LED, and designed to enable us to control light irradiation time, intensity, frequency and so on. Especially, to control the light irradiation frequency, FPGA was used, and to control the change of output value, TLC5941 was used. Control stage is divided into 30 levels by program. Consequently, the current value could be controlled by the change of level in Continue Wave(CW) and Pulse Width Modulation(PWM), and the output of a high brightness LED could be controlled stage by stage. And then, each experiment was performed to irradiation group and non-irradiation group for both Rat bone marrow and Rat tissue cells. MTT assay method was chosen to verify the cell increase of two groups and the effect of irradiation on cell proliferation was examined by measuring 590 nm transmittance of ELISA reader. As a result, the cell increase of Rat bone marrow and tissue cells was verified in irradiation group as compared to non-irradiation group. The fact that specific wavelength irradiation has an effect on cell vitality and proliferation is known through this study.

Characterization of Physicochemical Properties of Starch in Barley Irradiated with Proton Beam

  • Kim, Sang Kuk;Park, Shin Young;Kim, Hak Yoon
    • 한국작물학회지
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    • 제58권3호
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    • pp.260-266
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    • 2013
  • The study was carried out to determine the gel pasting properties of barley (Hordeum vulgare L. cv. Geoncheonheugbori) as affected by different proton beam irradiation. The ${\lambda}max$, blue value, and amylose content were significantly associated with increasing proton beam irradiation. The pasting time in barley flour irradiated with proton beam ranged 0.09 to 0.16 min shorter than nonirradiated barley flour. Gel pasting temperature ranged 57.4 to $60.5^{\circ}C$. Gel pasting temperature in barley flour decreased with increasing proton beam irradiation. Proton beam irradiation caused a significant decrease in the onset temperature (To), peak temperature (Tp), conclusion temperature (Tc) and enthalpy change (${\Delta}H$). Gelatinization range (R) in barley starch was more broaden than that of non-irradiated barley starch. Barley starches gave the strong diffraction peak at around $2{\Theta}$ values$15^{\circ}$, $18^{\circ}$, $20^{\circ}$, and $23^{\circ}$ $2{\Theta}$. Peak intensity tended to increase with increased proton beam irradiation. The granule crystallinity is closely associated with decreased amylose and increased amylopectin component. The crystallinity degree of barley starch irradiated with proton beam was significantly increased and it ranged from 24.9 to 32.9% compared to the non-irradiated barley starches. It might be deduced that proton beam irradiation causes significant changes of properties of starch viscosity in rice, especially at high irradiation of proton beam.

100kHz PWM LED 광조사가 백서 골수세포에 미치는 영향 (The effect of 100KHz PWM LED light irradiation on RAT bone-marrow cells)

  • 천민우;김성환;김영표;이호식;박용필;유성미;이희갑;김태곤
    • 한국전기전자재료학회:학술대회논문집
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    • 한국전기전자재료학회 2008년도 하계학술대회 논문집 Vol.9
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    • pp.512-513
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    • 2008
  • The study examined what effects 100kHz PWM LED light irradiation causes to bone marrow cells of SD-Rat when LED characterized cheap and safe is used onto the light therapy by replacing the low 1evel laser. We developed the equipment palpating cell proliferation using a high brightness LED. This equipment was fabricated using a micro-controller and a high brightness LED, and designed to enable us to control light irradiation time, intensity, frequency and so on. Especially, to control the light irradiation frequency, FPGA was used, and to control the change of output value, TLC5941 was used. Consequent1y, the current value could be controlled by the change of 1eve1 in Continue Wave(CW) and Pulse Width Modulation(PWM), and the output of a high brightness LED could be controlled stage by stage. MTT assay method was chosen to verify the cell increase of two groups and the effect of irradiation on cell proliferation was examined by measuring 590nm transmittance of ELISA reader. As a result, the cell increase of Rat bone marrow cells was verified in 100kHz PWM LED light irradiation group as compared to non-irradiation group.

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유기발광소자의 결정구조에 따른 Photocurrent 발광효율특성 연구 (Photocurrent multiplication process in OLEDs due to light irradiation and crystalline hole transporting layer)

  • 임은주;이기진;한우미;이정윤
    • 한국전기전자재료학회:학술대회논문집
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    • 한국전기전자재료학회 2002년도 하계학술대회 논문집 Vol.3 No.2
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    • pp.1026-1029
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    • 2002
  • We report the electric properties of organic light emitting diodes (OLEDs) by controlling the carrier density according to the crystalline of copper(II) phthalocyanine(CuPc) and the irradiation light intensity. OLEDs were constructed with indium tin oxaide (ITO)/CuPc/triphenyl-diamin (TPD)/tris-(8-hydroxyquinoline)aluminum (Alq3)/Al. The transport properties of OLEDs were changedby the heat-treatments of CuPc. The irradiation of red and blue light exciting CuPc, TPD and Alq3. And then we observed the carrier density of OLEDs.

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흰쥐 슬관절 고정 후 초음파 적용이 관절연골내 HSP70의 발현에 미치는 영향 (The Effects of Ultrasound Irradiation on the Heat Shock Protein 70(HSP70) Expression in Rat Knee Articular Cartilage after Immobilization)

  • 남기원
    • The Journal of Korean Physical Therapy
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    • 제17권3호
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    • pp.369-376
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    • 2005
  • The purpose of the study was for investigating the effect of therapeutic ultrasound irradiation on HSP70 expression in knee of degraded rat articular cartilage. Knee of ten Sprague-Dawley male rats were immobilized for 4 weeks and divided at random into the control and continuous ultrasound applicated group. The continuous ultrasound applicated group was irradiated with frequency 1MHz, intensity $1W/cm^2$ for 5 minutes. The control group was sham sonication. The immunoreactivity of HSP70 was increased in degraded articular cartilage after untrasound irradiation. These results suggest that therapeutic ultrasound can enhance HSP70 expression in degraded articular cartilage.

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Phosphamidon과 Profenofos의 광분해성 (Photodegradation of Phosphamidon and Profenofos)

  • 민경진;차춘근
    • 한국환경보건학회지
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    • 제26권2호
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    • pp.49-58
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    • 2000
  • The present study was performed to investigate photodegradation rate constants and degradation products of phosphamidon and profenofos by the USEPA method. The two pesticides were very stable in 16 days exposure of sunlight from September 3 to 22, 1999 and humic acid had no sensitizing effect on the photolysis of each pesticide in sunlight. In the UV irradiation test, phosphamidon was rapidly degraded as increasing UV intensity. In case of UV irradiation with TiO2 and with TiO2 powder amount, degradation of profenofos showed no significant difference with UV irradiation. Photodegradation rate of profenofos was slower than that of phosphamidon. In order to identify photolysis products, the extracts of degradation products were analyzed by GC/MS. The mass spectra of photolysis products of phosphamidon were at m/z 153 and 149, those of the profenofos were at m/z 208 and 240, respectively. It was suggested that the photolysis products of phosphamidon were 0, 0-dimethyl phosphate(DMP) and N, N-diethylchloroacetamide, those of profenofos were 4-bromo-2-chlorophenol and 0-ethyl-S-propyl phosphate.

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UV Effect on Plant Growth

  • Kondo, Noriaki;Tou, Seiji;Takahashi, Shinya;Nakajima, Nobuyoshi
    • Journal of Photoscience
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    • 제9권2호
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    • pp.158-161
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    • 2002
  • UV-B radiation gives harmful effects on plants, such as production of several types of DNA lesions, and growth inhibition. On the other hand, plants have some protective mechanisms, including filtering effect due to accumulation of phenolic compounds in epidermal cells and reactivation of DNA lesions, which are enhanced by UV-B irradiation. We have investigated the mechanism of UV-B effects on plants using cucumber seedlings as plant materials. Cucumber plants were cultivated in an artificially lit growth chamber. Supplemental UV-B irradiation, of which intensity was almost equal to the level of natural sunlight, retarded the growth of first leaves. The growth retardation must result trom the inhibition of cell division and/or cell growth. Microscopical observation of leaf epidermis suggested that the growth retardation might be mainly caused by cell growth inhibition. The retardation was, however, restored within 2 or 3 days after the termination of UV-B irradiation. It is known that UV-B irradiation lowers the activity of photo system II (PS II). In the present experimental conditions, however, UV-B irradiation has little effect on PS II activity as estimated by chlorophyll fluorescence. The stomatal conductance, a major factor determining photosynthetic rate, of first leaves increased during the growth. The increase of stomatal conductance was suppressed by UV-B irradiation and restored by termination of the irradiation. It has not been clear, however, what mechanisms are involved in the suppression of increase of stomatal conductance.

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