• 한국대기환경학회:학술대회논문집
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• 한국대기환경학회 2002년도 추계학술대회 논문집
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• pp.292-293
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• 2002

대기 중에서 HOx(OH, H $O_2$) 라디칼은 가장 중요한 산화제로서 광화학 반응의 핵심적 역할을 한다. 이러한 OH 라디칼의 정확한 농도를 측정하기 위한 여러 가지 시도가 있었으나, 그 존재량이 적고 수명이 짧기 때문에 측정에 많은 어려움이 있다. 간접적인 측정에 근거한 모델링과 계산적인 이론 값에 의하면 대류권에서의 전 지구적 평균 OH 라디칼의 농도는 대략 $10^{6}$molecules $cm^{-3}$이고, H $O_2$ 라디칼의 농도는 $10^{8}$molecules $cm^{-3}$정도로 추정된다. (중략)

• Bulletin of the Korean Chemical Society
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• 제25권8호
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• pp.1130-1132
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• 2004

Photodissociation dynamics of tert-butyl isocyanide at 193 nm has been investigated by measuring rotationally resolved laser induced fluorescence spectra of CN fragments that were exclusively produced in the ground electronic state. From the spectra, internal energies of CN and translational energy releases in the products were obtained. The dissociation takes place in the excited triplet states which are strongly repulsive along the dissociation coordinate via curve crossing from the initially prepared state.

• Bulletin of the Korean Chemical Society
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• 제29권9호
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• pp.1685-1688
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• 2008

• 한국추진공학회:학술대회논문집
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• 한국추진공학회 2004년도 제22회 춘계학술대회논문집
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• pp.1-14
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• 2004

Experiments were performed in order to examine the stability of hydrocarbon-fueled flames in cavity flameholders in supersonic airflows. Methane and ethylene were burned in two different cavity configurations having aft walls ramped at 22.5 and 90$^{\circ}$. Air stagnation temperatures were 590 K at Mach 2 and 640 K at Mach 3. Lean blowout limits showed dependence on the air mass flowrates. Visual observations, planar laser induced fluorescence (PLIF) of nitric oxide (NO), and Schlieren imaging were used to investigate these phenomena. Large differences were noted between cavity floor and cavity ramp injection schemes. Cavity ramp injection provided better performance in most cases. Ethylene pilots have a wider range of stable operation than methane. Fuel flowrates at ignition showed similar trends as lean blowout limits, but higher flowrates were required.

• Bulletin of the Korean Chemical Society
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• 제18권10호
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• pp.1076-1082
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• 1997

The infrared, Raman, and jet-cooled laser-induced fluorescence excitation spectra of 1,2,3,4-tetrahydronaphthalene have been recorded and analyzed. The observed vibrations have been assigned to understand the conformational behaviors in its electronic ground (S0) and excited (S1) states. Ab initio at the HF/6-31G** level and molecular mechanics (MM3) force field calculations have been carried out to generate the complete normal mode frequencies of the molecule in its S0 state. The vibrational frequencies calculated from the ab initio method show a better agreement with the observed infrared and Raman frequencies than those calculated from the MM3 method. In several cases, the normal mode calculations were very helpful to clarify some ambiguities of previous assignments. In addition, the ring inversion process between two twisted conformers of 1,2,3,4-tetrahydronaphthalene has been reexamined utilizing ab initio calculation. The results show that the ring inversion energy is in the range of 3.7-4.3 kcal/mol which is higher than the previously reported AM1 value of 2.1 kcal/mol.

• Bulletin of the Korean Chemical Society
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• 제16권4호
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• pp.341-344
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• 1995

Laser-induced fluorescence (LIF) excitation spectra were measured for fluorene (FR) cooled in pulsed supersonic expansions of He in the range 283.7-296.7 nm. Ab initio studies of FR have also been carried out for determining the electronic and vibrational structures by using the standard 3-21G basis sets. In the LIF excitation spectra of FR, highly resolved vibronic bands are observed having the band origin of 33,791 cm-1. The vibrational bands above the electronic origin were assigned on the basis of the well-characterized electronic vibrational bands reported previously and of normal modes of vibrations derived by our HF/3-21G calculations.

• 대한화장품학회지
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• 제36권3호
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• pp.215-219
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• 2010

본 연구에서는 발모의 성장결여로부터 모내기의 천연성분에 의한 침투력, 침투면적, 모발성장속도, 모발의 수 및 표면에 미치는 영향에 관하여 조사를 수행하였다. 제모를 통한 모발의 성장 속도와 모내기의 피부 침투력, 약물도달 부위를 CLSM710 공초점 현미경으로 관찰하였는데, 고삼, 단삼 및 인삼의 혼합물인 모내기를 $10\;{\mu}g/mL$ 농도로 처리한 그룹에서는 정상군과 대조군과 비교시 $33{\pm}4$과 $60{\pm}6$ (AFI: 인위적 형광강도)인데 반해, 약 $6782{\pm}67$ AFI (인위적 형광강도)으로 약 205배와 113배의 침투능력을 나타내었고 면적은 정상군과 대조군은 각각 약 $22{\pm}3$와 $44{\pm}6$ AFI인데 반해 모내기군은 약 $5602{\pm}45$ AFI였고 각각 255배와 127배 정도 침투면적의 확대되었음을 관찰하였다. 또한 confocal LSM700으로 관찰한 결과 대조군은 진피층에 존재하는 collagen IV에서 아무런 녹색형광이 없는 반면 모내기군은 collagen IV이 함유한 진피층에서 강한 녹색형광이 관찰하였는데, 이는 모내기 주성분이 피부 진피층까지 도달한 것이라 사료되고 남자 15명과 여자 5명 중 20대 4명(20 %), 30대 10명(50 %), 그리고 40대 이상 6명(30 %)의 내원환자의 탈모의 털 직경과 표면, 탈모의 수, 그리고 발모의 수를 조사하여 본 결과 평균 약 75 % 개선효과를 나타내므로 모내기의 천연성분이 발모인자의 활성화를 촉진하여 모낭 성장을 촉진시키는 기능을 유도하리라 사료된다.

• Biotechnology and Bioprocess Engineering:BBE
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• 제8권4호
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• pp.233-239
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• 2003

For the quantitative analysis of an unknown sample a calibration curve should be obtained, as analytical instruments give relative, rather than absolute measurements. Therefore, researchers should make standard samples with various known concentrations, measure each standard and the unknown sample, and then determine the concentration of the unknown by comparing the measured value to those of the standards. These procedures are tedious and time-consuming. Therefore, we developed a polymer based microfluidic device from polydimethylsiloxane, which integrates serial dilution and capillary electrophoresis functions in a single device. The integrated microchip can provide a one-step analytical tool, and thus replace the complex experimental procedures. Two plastic syringes, one containing a buffer solution and the other a standard solution, were connected to two inlet holes on a microchip, and pushed by a hydrodynamic force. The standard sample is serially diluted to various concentrations through the microfluidic networks. The diluted samples are sequentially introduced through microchannels by electro-osmotic force, and their laser-induced fluorescence signals measured by capillary electrophoresis. We demonstrate the integrated microchip performance by measuring the fluorescence signals of fluorescein at various concentrations. The calibration curve obtained from the electropherograms showed the expected linearity.

• 대한한방내과학회지
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• 제21권4호
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• pp.621-631
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• 2000

Objective : In this study, the medicine herbs above were directly treated to cultured normal lung cells and lung carcinoma cells, and the effects were investigated to develope new cancer treatments with increased anti-cancer efficiency as well as decreased side-effects and to suggest more useful clinical therapies. Materials and Methods : In the experiment, WI-26 VA lung normal cell line and A-427 lung carcinoma cell line were cultured. To observe the morphological change of the treated cells, were subjected to Giemsa staining and observed under Reflected Fluorescence microscope. To examine whether cell death occurred, cells observed under Reflected Fluorescence microscope, To investigate the degree of cell death in the nucleus, cells were screened by Laser cytometry ACAS 570. Results : Samgibopye-tang(Shenqibufei-tang) stimulated not only the growth of the normal cells but also that of the carcinoma cells, Wikyeung-tang(Weijing-tang) induced morphological change such as cytoplasmic constriction in the normal cells and the carcinoma cells, but it did not show any strong inhibitory effect on the cell growth. Samso-eum(Shensu-yin) caused severe cell damage in both cell lines, Eunkyo San(Yinqiao-san) significantly damaged the nuclei and caused weak cytoplasmic constriction in both cell lines, Normal cells treated with Gilgyeung-tang(Jingeng-tang) did not show any significant morphological change while some Gilgyeung-tang(Jingeng-tang) treated carcinoma cells were observed to have a normal cell-like shape, interestingly, conclusions : As the results above, Samgibopye-tang(Shenqibufei-tang), Wikyeung-tang(Weijing-tang), and Gilgyeung-tang(Jingeng-tang) helped the growth of both cell lines, and especially Samgibopye-tang(Shenqibufei-tang) showed the best effect, However, Samso-eum(Shensuyin) and Eunkyo-san(Yinqiao-san) caused lethal damage in the normal cells and also showed strong toxicity in the carcinoma cells.

• 분석과학
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• 제8권2호
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• pp.125-129
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• 1995

두 가지 활성제를 분포시킨 LaOCl:Pr, Tb와 LaOCl:Pr, Eu계에서 에너지 전달을 관찰하였다. 레이저에 의한 들뜨기와 형광 스펙트럼의 관찰로부터 활성제 이온들 사이에 독특한 에너지 전달 과정이 있음을 발견하였다. $Tb^{3+}$에서 흡수한 에너지는 $Pr^{3+}$로 직접 전달되었다. 들뜬 $Pr^{3+}$의 에너지가 아래 준위인 $^1D_2$로 단계적으로 풀리는 현상이 $Eu^{3+}$에 의해 야기되었다. 비슷한 조건을 가진 $Tb^{3+}$는 $Eu^{3+}$처럼 촘촘한 $^7F_J$ 바닥 준위를 가지고 있으나 단계적 풀림에 효과적이지 못하였다. 이 결과는 에너지 전달에 있어서 이온의 양자 상태가 에너지 전달에 절대적인 조건이 되지 못하며 에너지 전달은 활성제가 가까이 있을 경우 그 준위들 사이에 경쟁적임을 보여 주었다.