• 한국응용과학기술학회지
• /
• 제32권2호
• /
• pp.330-338
• /
• 2015

N-propyl-N,N-dimethylethanolamine의 산란혼탁매질에서 형광, 산란과 응집의 영향은 파장 과 산란된 형광세기로 나타내는데, laser induced fluorescence(LIF) 분광학에 의한 분자특성으로 나타난다. 산란매질에서 광학적 효과는 광학적 파라미터들(${\mu}_s$, ${\mu}_a$, ${\mu}_t$)에 의해 표현되고 응집은 고-액상 분리 공정에서 중요하게 활용되고 있다. 따라서 입자가 서로 접근될 때 콜로이드 입자들의 상호작용을 LIF와 응집효과로 분석하였다. Monte Carlo simuation과 실험으로 레이저 광원에서 검출기까지 거리의 함수에 의해 농도가 묽어짐에 따라 산란세기가 기하급수적으로 감소함을 알 수 있었다. 이는 유지화학, 생의학, 레이저 의학, 의공학 분야적용에 LIF와 입자이동 현상은 아주 적합한 모델 연구에 큰 도움이 될 것이다.

• 한국자동차공학회논문집
• /
• 제8권2호
• /
• pp.64-71
• /
• 2000

In order to clarify the characteristics of soot formation and oxidation in-cylinder of a diesel engine, it is necessary to diagnose accurately for combustion of in-cylinder. The past techniques for soot measurement have limitations in providing the characteristics of soot in a diesel engine, whereas, laser-based 2D imaging diagnostics have the potential to provide better temporally and spatially resolved measurements of the soot distribution. We rebuilt an optically accessible diesel engine which is similar to the conditions of a conventional engine and tried to measure soot distribution in a cylinder of the diesel engine using laser induced scattering(LIS) and laser induced incandescence(LII). Some results were acquired in this study. LIS and LII signal that show soot distribution of a in-cylinder were taken by ICCD properly. The signal of LIS was intenser than that of LII. Although they have some differences of signal intensity in early combusion period, both of signals show that they are generally similar in late combustion period, after ATDC 50 degree.

• 한국진공학회:학술대회논문집
• /
• 한국진공학회 2012년도 제43회 하계 정기 학술대회 초록집
• /
• pp.149-149
• /
• 2012

We introduce Helicon discharge plasma source and Laser Thomson scattering system recently finished an installation in KRISS. Laser Thomson scattering method is promising for diagnostics in Helicon plasma because a measurement by electrical probe typically used has significant errors due to the gyromotion of electrons induced by high magnetic field. However, we found that LTS is affected by magnetic field so that we applied the normalization method for processing data and the results show a clear Maxwellian distribution at various conditions of magnetic field and RF power at low energy part without distortion.

• Bulletin of the Korean Chemical Society
• /
• 제30권1호
• /
• pp.242-244
• /
• 2009

• 한국가시화정보학회지
• /
• 제3권2호
• /
• pp.3-13
• /
• 2005

The optical patterantor provides the high resolution and quantitative information of the spray. Fuel distribution and Sauter Mean Diameter (SMD) can be measured from fluorescence and Mie-scat-tering images. To correct the attenuation of the laser beam and signal in dense spray region, the method to find the geometric mean of the signal intensities obtained from two cameras was evaluated and verified in a solid-cone spray. In high pressure environment, the increased number density of the droplets cause multiple scattering. The optical patternation technique using a laser beam instead of a laser sheet was applied to minimize the multiple scattering problem. The pattern of a coaxial spray was changed from hollow-cone to solid-cone shape, and the spray angle was reduced as the ambient pressure increased from 0.1 to 4.0 MPa.

• 한국응용과학기술학회지
• /
• 제16권4호
• /
• pp.329-335
• /
• 1999

The influences of fluorophor, scatterer, and absorber in turbid material by light scattering were interpreted for the scattered fluorescence intensity and wavelength. The molecular properties have been studied by laser induced fluorescence spectroscopy in phantom. It has been found that the effects of optical properties in scattering media could be investigated by the optical parameters(${\mu}_a$, ${\mu}_a$, ${\mu}_t$). Experimental and Monte Carlo Simulation method for modelling light transport in tissue was applied. The experimental results using a phantom were discussed and compared with those obtained through Monte Carlo Simulation. It may also aid in designing the best model for oil chemistry, medicine and application of medical engineering.

• 한국응용과학기술학회지
• /
• 제31권2호
• /
• pp.167-175
• /
• 2014

혼탁매질에서 형광, 산란과 응집의 영향은 파장과 산란된 형광세기로 나타내는데, laser induced fluorescence(LIF) 분광학에 의한 분자특성으로 나타난다. 산란매질에서 광학적 효과는 광학적 파라미터들(${\mu}_s$, ${\mu}_a$, ${\mu}_t$)에 의해 표현되고 응집은 고-액상 분리공정과 Photodynamic therapy에서 중요하게 활용되고 있다. 따라서 입자가 서로 접근될 때 콜로이드 입자들의 상호작용을 LIF와 응집효과로 분석하였다. 우리는 레이저 광원에서 검출기까지 농도의 함수에 의해 in vitro 시료의 산란과 형광 스펙트라를 측정하였다. 산란계수 ${\mu}_s$는 산란체의 입자가 증가함에 크게 나타났다. 그리하여 Phorphyrin A는 Phorphyrin C보다 산란세기는 증가하였으나, 침투깊이 ${\delta}$는 감소하였다.

• 한국응용과학기술학회지
• /
• 제33권1호
• /
• pp.136-142
• /
• 2016

무질서 매질에서 형광, 산란과 응집의 영향은 파장과 산란된 형광세기로 나타내는데, laser induced fluorescence(LIF) 분광학에 의한 분자특성으로 나타난다. 산란매질에서 광학적 효과는 광학적 파라미터들(${\mu}_s$, ${\mu}_a$, ${\mu}_t$)에 의해 표현되고 응집은 고-액상 분리공정과 Photodynamic therapy에서 중요하게 활용되고 있다. 따라서 입자가 서로 접근될 때 콜로이드 입자들의 상호작용을 LIF와 응집효과로 분석하였다. 우리는 레이저 광원에서 검출기까지 거리의 함수에 의해 in vitro 시료의 산란과 형광 스펙트라를 측정하였다. 산란계수 ${\mu}_s$는 산란체의 입자가 증가함에 크게 나타났다. 그리하여 purple membrane vesicle과 ${\beta}$-carotene의 혼합물의 매질에서 광원에서 검출기에 의한 거리에 대한 측정된 값(I, ${\delta}$)이 거리가 가까워짐에 따라 크게 나타났다.

• 한국연소학회:학술대회논문집
• /
• 한국연소학회 2000년도 제21회 KOSCO SYMPOSIUM 논문집
• /
• pp.183-193
• /
• 2000

Soot formation and oxidation is closely related to the combustion phenomena inside a diesel engine. Laser-based diagnostics provide a means for improving our understanding of diesel combustion, because they have highly temporal and spatial ability. To understand the soot behavior we did preliminary study by taking flame luminosity photographs and 2-D images of soot distribution using Laser Elastic Scattering(LIS) and Laser-Induced Incandescence(LII). From the data we found that soot concentration was high in the bowl and disappeared from the central region in the late combustion stage and that soot exists in the flame using luminosity, LIS and LII.

• 대한전기학회:학술대회논문집
• /
• 대한전기학회 2005년도 추계학술대회 논문집 전기물성,응용부문
• /
• pp.220-222
• /
• 2005

We can classify two cases in a way to observe an atom of gas state or a molecule using the laser. First case is way to use dispersion phenomenon like Rayleigh scattering, Thomson scattering, Mie scattering, Raman Scattering. And Second case is a way to use change phenomenon like a LAS (Laser Absorption Spectroscopy), LIF (Laser Induced Fluorescent). In this paper, we have measured the meta-stable density and the distribution by using a LAS method in Xe discharge lamp. The laser absorption spectroscopy (LAS) is useful to investigate the behavior of such species. The xenon atoms in the $1S_4$ and $1S_5$ generate excited $Xe^*$(147nm) and $Xe_{2}^*$(173nm) dimers in Xe plasma. It is found that the intensity of VUV 147nm emission is proportional to that of the IR 828nm emission, and the VUV 173nm emission is roughly proportional to that of the IR 823nm emission. The laser is used CW laser that consist of AlGaAs semiconductor and energy level is used 823.16nm wavelength. We measured signal of monochrometer from the lamp center while will change a discharge electric current by 6mA in 3mA and calculated meta-stable state density of a xenon atom through a measured value.