• Bulletin of the Korean Chemical Society
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• v.23 no.2
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• pp.229-240
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• 2002

Quantum mechanical calculation is performed for the $O(^1D)$ + HCl ${\rightarrow}$OH + Cl reaction using Reactive Infinite Order Sudden Approximation. Shifting approximation is also employed for the l ${\neq}$ 0 partial wave contributions. Various dynamical quantities are calculated and compared with available experimental results and quasiclassical trajectory results. Vibrational distributions agree well with experimental results i.e. product states mostly populated at $v_f$ = 3, 4. Our results also show small peak at $v_f$ = 0, which indicates bimodal vibrational distribution. The results show two significant broad peaks in ${\gamma}_i$ dependence of the cross section, one is at ${\gamma}_i$ = $15^{\circ}-35^{\circ}$ and the another is at ${\gamma}_i$= $55^{\circ}-75^{\circ}$ which can be explained as steric effects. At smaller gi, the distribution is peaked only at higher state ($v_f$ = 3, 4) while at the larger gi, both lower state ($v_f$ = 0) and higher state ($v_f$ = 3, 4) are significantly populated. Such two competing contributions (smaller and larger ${\gamma}_i$) result in the bimodal distribution. From these points we suggest two mechanisms underlying in current reaction system: one is that reaction occurs in a direct way, while the another is that reaction occurs in a indirect way.

• Korean Journal of Microbiology
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• v.30 no.3
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• pp.232-238
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• 1992

Canz~~j~lohuc;tc.~jurn i werc studied for their heat shock responses at several elevated temperatures and their heat shock genes were detected by the technique of Southern hybridization. (.. ,jc\ulcorneruni sy~>thesized the major heat shock proteins of hsp90. hsphh. and hsphO at 48$^{\circ}$C . ant1 their w~u.ival rates were maintained as the same level at optimal temperature. '1-hc heat shock genes in chromosome of C ,jc:jutii werc determined to be homologous to the heat shock genes or E. t,oli. by showing strong signals in Southern hybridization analysis using clnaK and groESL- as DNA probe But the restriction sites for thc fragmcnts including heat shock genes were different betueen E. c,oli and C ,jtjuni.

• Journal of Sensor Science and Technology
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• v.3 no.2
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• pp.65-73
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• 1994

TO:F($SnO_{2}:F$) thin films were prepared by RF magnetron sputtering system. The dependence of their structural, electrical, and optical properties on deposition conditions such as substrate temperature, working pressure and power was studied. The optimum conditions of TO:F thin film are $SnF_{2}$ content of 15wt.% in target, RF power of 150W, substrate temperature of $150^{\circ}C$ and working pressure of 2mmTr. The resistivity and transmittance at 550nm in visible spectrum of the TO:F film deposited at optimum condition are $9{\times}10^{-4}{\Omega}{\cdot}cm$ and above 85%, respectively. For the films deposited from the target without $SnF_{2}$ and with 15wt.% $SnF_{2}$, the optical bandgaps calculated from the transmittance curves are 3.84 and 3.9eV, respectively. X-ray diffraction patterns showed that TO and TO:F films had tetragonal rutile structure with (101), (200) direction.

• Korean Journal of Materials Research
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• v.6 no.7
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• pp.684-691
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• 1996

To enhance the formation of Bi,Sr,Ca,Cu,O,(Bi-2223) single phase in a shorter reaction time, the intermediate compounds such as Bi,Sr,CuO,(Bi-2201). BizSr,CaCuz08(Bi-2212) and (Ca, Sr,, ,9)CuOz in the Bi-Sr-Ca-Cu-0 system were used as the precursors. The formation of Bi-2223 was enhanced in the mixture of Bi-2201 and (Ca, ,,Sr, 119)C~eOsZpe,c ially from the mixture with (Ca, 9I Sr, ,,)CuO,-rich composition compared to Bi, iPb, 4Sr2Ca,Cu3010-cxo mposition. The formation of Bi- 2223 essentially completed within 60h at 860$^{\circ}$C and 870$^{\circ}$C. However, a small amount of the remnant Bi-2212 phase did not disappear even after a prolonged reaction at 870'C. The merit of the proposed synthetic method using the intermediate precusors can be summarized as a shorter reaction time for the formation of Bi-2223 phase, in addition to a smaller amount of second phases compared to the conventional solid-state reaction method.

• Journal of the Korean Institute of Telematics and Electronics A
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• v.28A no.12
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• pp.59-64
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• 1991

Thin (25-103$\AA$) SiO$_2$ films are grown using the rapid thermal oxidation processing at temperatures of 105$0^{\circ}C$-115$0^{\circ}C$ for 5-30 sec, in order to investigate the characteristics of ultra thin oxide. For measuring the thickness of oxide TEM, ellipsometry, and C-V method which is taken in the condition of small surface band bending are used and compared. When neglecting the small deviation affected by both interface state and moisture charge effect, those three methods described above give similar results. In order to examine the effect of rapid thermal annealing, part of samples are annealed in N$_2$ ambient. MOS capacitors are fabricated and the characteristics of I-V and C-V are measured. Measurements show that the activation energy of initial thickness of oxide grown during the ramp-up time is of 1.125eV and the activation energy of the oxidation rate is of 0.98eV. As oxidation temperature is increased, dielectric breakdown field E$_{BD}$ is decreased due to the increase of fixed charge density N$_f$ However, E$_{BD}$ is shown to be decreased as increasing the thickness of oxide. The increase of N$_f$ in the early stage of thermal annealing results in the decrease of E$_{BD}$.

• Journal of the Society of Cosmetic Scientists of Korea
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• v.23 no.3
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• pp.24-38
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• 1997

Using the all-trans-retinol which is double-capsulated with matrix, we investigated its stability and the change of the epidermal thickness. The proprietary MDC comprise two steps of capsulation of retinol, i.e., primary microcapsulation with collagen and then secondary capsulation with gellan gum. We compared the activity of all-trans-retinol in various forms such as (1) simply in O/W, (2) in W/O emulsion, (3) in primary capsulted form in O/W emulsion, or (4) in MDC in O/W emulsion. After storage at 45$^{\circ}C$ for 4 weeks, retinol in MDC in O/W emulsion retained 92% of the activity compared to the standard material upon HPLC analysis, whereas the primary capsule gave 70%, the O/W emulsion form 47% and the W/O emulsion 78%. The retinol in MDC in O/W induced the siginificant increase in epidermal thickness compared to the vehicle.

• Proceedings of the KIEE Conference
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• 1994.07b
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• pp.1487-1489
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• 1994

$(Zr_{0.65}Sn_{0.35})Ti_{1.04}O_4$ system which has a dielectric constant, low dielectric loss and temperature coefficient was investigated. Temperature coefficient varied from positive to negative with increasing of NiO. For the NiO content 1.0wt%. i.e $(Zr_{0.65}Sn_{0.35})Ti_{1.04}O_4$, the ceramic showed very good dielectric properties such as ${\epsilon}$=37.8, $Q{\times}f_o=49.000$ and ${\tau}_r= 4{\pm}1ppm/^{\circ}C$.

• Proceedings of the Materials Research Society of Korea Conference
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• 2003.11a
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• pp.208-208
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• 2003

RF 마그네트론 스퍼터링법을 이용하여 Ar과 $O_2$의 유량을 25sccm씩 흘리면서 $SiO_2$/Si기판 위에 Sn $O_2$ 박막을 증착하였다. 증착된 박막은 columnar 구조로 성장하였으며 많은 입자들이 뭉쳐서 형성된 양배추꽃(cauliflower) 형태의 뭉친 입자(agglomerates)를 가지는 표면형상이 관찰되었다. 분위기에 따른 어닐링 효과를 확인하기 위하여 50$0^{\circ}C$에서 공기와 질소 분위기하에서 열처리하였다. 열처리한 후 표면거칠기가 개선되었으며, 표면형상의 변화가 발생하였다. 특히 50$0^{\circ}C$, 질소분위기에서 어닐링한 경우는 양배추꽃 형태의 표면형상이 소수의 작은 입자가 뭉친 형태로 분리되면서 입도분포가 개선되었다. 이러한 결과는 어닐링 과정에서 발생되는 응력을 완화시키기 위하여 표면형상의 변화가 발생하는 것으로 판단된다. XPS 측정 결과, 질소 분위기에서 어닐링한 후에 OIs와 Sn5/3d 피크가 낮은 결합에너지에 위치하고 있어 산소공공의 농도가 어닐링 전에 비하여 증가하였음을 확인할 수 있다. 어닐링 전후에 Sn $O_2$ 박막의 면저항 측정 값은 XPS 결과와는 달리 질소 분위기 어닐링한 후에 오히려 면저항값이 크게 증가하였다. 이러한 결과는 질소 분위기 어닐링한 후 표면형상의 변화에 기인하여 입자간의 연결성이 저하되어 면저항값이 증가한 것으로 추정된다. 산소분위기에서 어닐링한 후에 전체적으로 전기적 특성의 재현성이 개선되었으며 Sensitivity( $R_{air}$/ $R_{gas}$)가 향상되었음을 확인하였다.하였다.석을 통하여 La의 분포를 확인하였으며, HRTEM 분석을 통하여 미세구조분석을 실시하였다.2463eV였다. 10K에서 광발광 봉우리의 919.8nm (1.3479eV)는 free exciton(Ex), 954.5nm (1.2989eV)는 donor-bound exciton 인 I2(DO,X)와 959.5nm (1.2921eV)는 acceptor-bound exciton 인 I1(AO,X) 이고, 964.6nm(1.2853eV)는 donor-acceptor pair(DAP) 발광, 1341.9nm (0.9239eV)는 self activated(SA)에 기인하는 광발광 봉우리로 고찰되었다.가 높을수록 방출전류가 시간에 따라 급격히 감소하였다. 각 duty비에서 방출전류의 양이 1/2로 감소하는 시점을 에미터의 수명으로 볼 때 duty비 대 에미터 수명관계를 구해 높은 duty비에서 전계방출을 시킴으로써 실제의 구동조건인 낮은 duty비에서의 수명을 단시간에 예측할 수 있었다. 단속적으로 일어난 것으로 생각된다.리 폐 관류는 정맥주입 방법에 비해 고농도의 cisplatin 투여로 인한 다른 장기에서의 농도 증가 없이 폐 조직에 약 50배 정도의 고농도 cisplatin을 투여할 수 있었으며, 또한 분리 폐 관류 시 cisplatin에 의한 직접적 폐 독성은 발견되지 않았다이 낮았으나 통계학적 의의는 없었다[10.0%(4/40) : 8.2%(20/244), p>0.05]. 결론: 비디오흉강경술에서 재발을 낮추기 위해 수술시 폐야 전체를 관찰하여 존재하는 폐기포를 놓치지 않는 것이 중요하며, 폐기포를 확인하지 못한 경우와 이차성 자연기흉에 대해서는 흉막유착술에 더 세심한 주의가 필요하다는 것을 확인하였다. 비디오흉강경수술은 통증이 적고, 입원기간이 짧고,

• Journal of Astronomy and Space Sciences
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• v.24 no.4
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• pp.349-366
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• 2007

We designed and developed a multi-purpose CCD camera system for three kinds of CCDs; KAF-0401E($768{\times}512$), KAF-1602E($1536{\times}1024$), KAF-3200E($2184{\times}1472$) made by KODAK Co.. The system supports fast USB port as well as parallel port for data I/O and control signal. The packing is based on two stage circuit boards for size reduction and contains built-in filter wheel. Basic hardware components include clock pattern circuit, A/D conversion circuit, CCD data flow control circuit, and CCD temperature control unit. The CCD temperature can be controlled with accuracy of approximately $0.4^{\circ}C$ in the max. range of temperature, ${\Delta}33^{\circ}C$. This CCD camera system has with readout noise $6\;e^-$, and system gain $5\;e^-/ADU$. A total of 10 CCD camera systems were produced and our tests show that all of them show passable performance.

• Journal of the Korean Ceramic Society
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• v.33 no.2
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• pp.242-250
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• 1996

Glasses of Na2O-Al2O3-SiO2 system were prepared and ion-exchange characteristics change of properties and bactericidal effects by Na+↔Ag+ ion exchange were studied. Parent glasses with three compositions of varying Na2O in the 20~30 wt% were ion-exchanged in the molten salt of 2 mol% AgNO3+98 mol% NaNO3 at 320~36$0^{\circ}C$ for 15~16min. Amount of ion exchange and penetration depth of Ag+ ion increased with Na2O content in the parent glass ion exchange temperature and time. After ion exchange densities and Vickers hardness of the glasses increased and the glasses showed yellow-brown color and as amount of ion exchange increased the color turned deep because partial reduction and agglomeration of Ag+ into Ag0 results in absorption of visible light. After ion exchange chemical durability of the glass to wter was enhanced compara-bly that weight loss and change of surface of the glass were not found for the leaching test in 5$0^{\circ}C$ K.I water for 240hrs. Bactericidal effect of ion exchanged glass on Staphylococcus aureus and E. coli was determined by microorganism test and bactericidal effect increased with amount of ion exchange and incubation time.