• 한국지하수토양환경학회지:지하수토양환경
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• 제20권1호
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• pp.36-40
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• 2015

This study examined the disinfection in combined sewer overflows (CSOs) by pulsed ultraviolet (PUV). The reflectors (stainless steel. mirror, aluminium foil, aluminium (1050), aluminium (6061), aluminium (5052), and aluminium mirror) of PUV irradiation was performed in a 90 L stainless reactor at a constant temperature of $20^{\circ}C$ and an applied power of 4000 W. The reflection efficiency of reflectors were showed 1.00 (aluminium mirror) ~ 1.48 (aluminium foil) does. The case of a rough surface analysis using SEM showed high reflectance, was the case of a smooth surface and a low reflectivity. Pseudo first-order rate constant calculated results, has a higher reflectivity values were more than twice as high compared to the low reflectivity. Affected Total coliforms disinfection time, depending on the type of reflector is considered.

• 센서학회지
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• 제22권5호
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• pp.357-363
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• 2013

An ultraviolet pulsed laser ablation of polyimide film coated with platinum has been used to enhance the sensitivity for the application as an electrochemical biosensor. Densely packed cones are formed on polyimide surface after UV irradiation which results in increase of surface area. In order to apply the sensitivity improvement of laser ablated polyimide film electrodes, the glucose oxidase modified biosensor was fabricated by using an encapsulation in the gel matrix through sol-gel transition of tetraethoxysliane on the surface of laser ablated polyimide film. The optimum conditions for glucose determination have been characterized with respect to the applied potential and pH. The linear range and detection limit of glucose detection were from 2.0 mM to 18.0 mM and 0.18 mM, respectively. The sensitivity of glucose biosensors fabricated with laser ablated polyimide film is about three times higher than that of plain polyimide film due to increase in surface area by laser ablation.

• 대한환경공학회지
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• 제39권10호
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• pp.575-580
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• 2017

전 세계적으로 지하수에서 TCE, PCE, BTEX, PAH, TPH, TNT, RDX, HMX가 지속적으로 검출되고 있다. 이러한 오염물질들은 기존의 물리화학적 방법으로 제거시에는 한계가 있으며, 신속한 정화를 요구하는 현장에 적용하기에는 많은 어려움이 있는 실정이다. 이에 본 연구에서는 난분해성 오염물질의 제거를 위해 PUV와 US를 연계하여 적용하고자 하였다. 각 공정은 고 에너지를 주입하는 PUV 공정과 라디칼 생산을 통해 오염물을 제거하는 US 공정의 특징을 이용하였으며, 제거율 향상을 위한 촉매주입도 함께 고려하였다. 연구 결과 PUV-US 하이브리드 시스템의 상승효과는 TCE, PCE, BTEX, TNT, RDX, HMX를 처리하는데는 90% 이상의 제거율을 나타내 적용 가능한, 효과적인 공정으로 판단되었으나 PAHs 제거를 위해서는 추가적인 공정 개선이 필요한 것으로 나타났다.

• 한국재료학회지
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• 제11권4호
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• pp.319-323
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• 2001

펄스레이저 증착법 (PLD)으로 (0001)면 사파이어 기판 위에 성장시킨 ZnO 박막의 두게 변화가 표면형상, 결정성 및 전기/광학적 특성에 미치는 효과에 대하여 조사하였다. SEM 및 XRD 분석을 통해 약 4000 의 두께에서 3차원 island들이 생성되며, 박막의 두께가 증가함에 따라 결정립의 크기가 증가하고, 결정성이 향상되었음을 알 수 있었다 상온에서의 PL 측정을 통해 두께가 증가함에 따라 ultraviolet(UV) 및 deep level emission peak의 강도가 급격히 증가함을 알 수 있었다. Hall측정 결과, 모든 박막들이 H형 전도도를 보였고, 운반자농도가 $10^{19}$ $cm^{-3}$ 이상이었으며, 두께가 증가할수록 운반자농도가 감소하여 약 4000 에서 포화되는 경향을 보였다. 따라서, 사파이어 기판 위에 증착시킨 ZnO 박막은 약 4000 의 두께에서 bulk ZnO의 특성을 나타내었다.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2005년도 춘계학술대회 논문집 디스플레이 광소자 분야
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• pp.51-53
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• 2005

$Zn_{1-x}Cd_xO$ thin films were grown on (0001) sapphire substrates by pulsed laser deposition. The energy bandgap of $Zn_{1-x}Cd_xO$ films decreases withincreasing Cd content. An increase of Cd content also leads to the emission broadening and degraded crystallinity. The absorption edge and ultraviolet emission peak shift to lower energy from 3.357 eV to 3.295 eV and 3.338 eV to 3.157 eV, respectively, with increasing Cd content from 0.3% to 3%. The Stokes' shift between the absorption and emission indicates the increase of localization of exciton with Cd content.

• 한국세라믹학회지
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• 제47권4호
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• pp.329-332
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• 2010

In order to investigate the effect of tail state on the electrical and the optical properties in amorphous IGZO(a-IGZO), a-IGZO films were deposited at room temperature on fused silica substrats using pulsed laser deposition method. The laser pulse energy was used as the processing parameter. In-situ post annealing was carried out at $150^{\circ}C$ right after the film deposition. The $O_2$ partial pressure during the deposition and the post annealing was fixed to 10mTorr. The carrier mobility of the a-IGZO films had a range from 2 to $18\;cm^2/Vs$ at carrier concentrations greater than $10^{18}\;cm^{-3}$. As the laser energy density increased, the Hall mobility increased. And post annealing improved the Hall mobility, as well. The optical property was examined using the ultraviolet-visible spectroscopy. The a-IGZO films that have low Hall mobility exhibited stronger and broader absorption tails in >3.0 eV region. Post annealing reduced the intensity of the tail-like absorption. The absorption tail in a-IGZO films is an important factor which affects the electrical and the optical properties.

• 한국진공학회:학술대회논문집
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• 한국진공학회 1998년도 제14회 학술발표회 논문개요집
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• pp.17-17
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• 1998

Synchrotron radiation is produced when charged particles moving with relativistic velocities a are accelerated - for example, deflected by the bending magnets which guide the electron or p positrons in circular accelerators or storage rings. By using special focusing magnetic lattices i in the particle accelerators it is possible to make the dimensions of the particle beam very small with a hi맹 charge density which results in a light source with high b디lIiance. Synchrotron light h has important properties which make it ideal for a wide range of investigations in surface s science. The fact that the spectrum of electromagnetic radiation emitted in a bending magnet e extends in a continuum from the 얹r infra red region to hard x-rays means that it is id않I for a v variety of spectroscopic studies. Since there are no convenient lasers, or other really bright l light sources, in the vacuum ultraviolet and soft x-ray re.밍ons the development of synchrotron r radiation has enabled enormous advances to be made in this di펌C비t spectr따 re밍on. P Polarization-dependent measurements, for ex없nple ellipsometry or circular dichroism studies a are possible because the radiation has a well-defined polarization - linear in the plane of orbit w with additional right-circular, or left-circular, components for emission an생es above, or below, t the horizontal, respectively. Since the synchrotron light is emitted from a bunch of charge c circulating in a ring the light is emitted with a well-defined time structure with a short flash of l light every time a bunch passes an exit port. The time structure depends on the size of the ring a and the number and sequence of filling of the bunches. A pulsed light source enables time¬r resolved studies to be performed which provide direct information on the lifetimes and decay m modes of excited states and in addition opens up the possibility of using time of flight t techniques for spectroscopic studies. The fact that synchrotron radiation is produced in a clean u ultrahi야 vacuum environment is of gr않t importance for surce science studies. The current t비rd generation synchrotron light sources provide exceptionally high baliance and stability a and open up possibilities for experiments which would have been inconceivable only a short time ago.

• 한국식품과학회지
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• 제51권6호
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• pp.551-557
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• 2019

본 연구는 소비자들의 식품안전과 위생에 대한 요구가 강해짐에 따라 식중독의 위험에 노출되어 있는 분말식품 중 전세계적으로 널리 사용되는 향신료 중 하나인 후춧가루의 비가열 살균 처리 방법에 따른 향미특성 변화를 비교 분석하였다. 색도 측정 결과 색도차(ΔE)는 저온 플라즈마와 자외선 살균처리 후에도 육안에 의한 인식 한계인 1.5 내외로 유지되었고, 광펄스 처리 후에는 6.58로 큰 차이를 보였다. Piperine 함량 정량 결과는 살균 전 후추가 10.7±0.53 mg/g로 가장 많았으며 자외선 살균처리(9.5±0.35 mg/g), 저온 플라즈마 살균처리(9.0±0.15 mg/g), 광펄스 살균처리(4.4±0.17 mg/g) 순으로 광펄스 58.9%, 저온 플라즈마 15.9%, 자외선 11.2%의 감소율을 보였다. 전자코 분석 결과 살균 처리 전후가 제 1주성분에 의해 두 그룹으로 구분되어 명확하게 향의 차이가 나타났으며, 제 1주성분과 제 2주성분에 의해서는 세 개의 그룹으로 나뉘었다. 강도평가 결과 살균처리 전, 광펄스, 저온 플라즈마, 자외선 살균처리 후 순으로 후추 향과 맛이 강하다고 응답했으며, 광펄스와 저온 플라즈마 살균처리 후의 후추는 유의적인 차이를 보이지 않았다. 강도평가 결과와 piperine 함량 정량과는 차이가 있었으며, 전자코 분석 결과와는 유사했다. 정량적 묘사분석(QDA)를 통해 13개의 관능적 언어가 개발되었다. 살균처리 후의 시료가 마른 솔잎향과 떫은맛, 고소한맛을 제외한 모든 항목에서 살균처리 전의 시료보다 관능적 특성이 낮게 나타났다. 이를 통해 살균처리 방법에 따라 후추향과 맛에 영향을 끼쳤음을 알 수 있었다. 또한 piperine 함량을 통해 후추 맛의 강도를 평가하기에는 어려움이 있으며 전자코 분석을 통해서 후추향의 강도를 평가하는데 중요한 자료로 사용될 수 있다고 판단된다.

• 한국산업보건학회지
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• 제17권2호
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• pp.81-88
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• 2007

The aim of this study was to investigate whether the exposure to vinyl chloride monomer(VCM) induces lipid peroxidation in workers by evaluating the concentration of malondialdehyde(MDA) in the urine in order to assess worker's oxidative stress due to exposure of vinyl chloride monomer. The subjects investigated in the study were divided into the experimental group; 18 workers exposed to VCM, and the control group; 19 workers unexposed to VCM. A gas chromatography/pulsed flame photometric detector(GC/PFPD) was utilized to analyze thiodiglycolic acid(TDGA), which was methylated with trimethylsilyldiazomethane (2.0M in diethyl ether) in urine and the urinary MDA, the product of lipid peroxidation, was determined by high-performance liquid chromatography/ultraviolet-visible detector after derivatized with 2,4-dinitrophenylhydrazine(DNPH). The concentrations of urinary TDGA in controls and VCM exposure workers were 0.13(2.01)mg/g Cr. GM(GSD) and 0.35(1.96)mg/gCr. GM(GSD), respectively. The concentrations of urinary MDA were $0.12(2.21){\mu}mol/gCr$. GM(GSD) in controls and $1.35(1.79){\mu}mol/gCr$. GM(GSD) in VCM exposure workers. As a result of simple regressions analysis between urinary concentration of TDGA and MDA in VCM exposure workers, it was found that the $R^2$ value was 0.261 (p=0.03) and the drinking and smoking did not affect their level. In conclusion, the workers exposed to VCM have a potentially to suffered by oxidative stress due to VCM exposure and the urinary MDA can be applicable to the marker of effect to assess the level of worker's VCM exposure.

• Journal of Ginseng Research
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• 제45권1호
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• pp.1-21
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• 2021

Panax species have gained numerous attentions because of their various biological effects on cardiovascular, kidney, reproductive diseases known for a long time. Recently, advanced analytical methods including thin layer chromatography, high-performance thin layer chromatography, gas chromatography, high-performance liquid chromatography, ultra-high performance liquid chromatography with tandem ultraviolet, diode array detector, evaporative light scattering detector, and mass detector, two-dimensional high-performance liquid chromatography, high speed counter-current chromatography, high speed centrifugal partition chromatography, micellar electrokinetic chromatography, high-performance anion-exchange chromatography, ambient ionization mass spectrometry, molecularly imprinted polymer, enzyme immunoassay, 1H-NMR, and infrared spectroscopy have been used to identify and evaluate chemical constituents in Panax species. Moreover, Soxhlet extraction, heat reflux extraction, ultrasonic extraction, solid phase extraction, microwave-assisted extraction, pressurized liquid extraction, enzyme-assisted extraction, acceleration solvent extraction, matrix solid phase dispersion extraction, and pulsed electric field are discussed. In this review, a total of 219 articles published from 1980 to 2018 are investigated. Panax species including P. notoginseng, P. quinquefolius, sand P. ginseng in the raw and processed forms from different parts, geographical origins, and growing times are studied. Furthermore, the potential biomarkers are screened through the previous articles. It is expected that the review can provide a fundamental for further studies.