• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2003년도 하계학술대회 논문집 Vol.4 No.1
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• pp.155-159
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• 2003

Polycrystalline $Ti_{1-x}Co_xO_2$ thin films on $SiO_2$ (200 nm)/Si (100) substrates were prepared using liquid-delivery metalorganic chemical vapor deposition. Microstructures and ferromagnetic properties were investigated as a function of doped Co concentration. Ferromagnetic behaviors of polycrystalline films were observed at room temperature, and the magnetic and structural properties strongly depended on the Co distribution, which varied widely with doped Co concentration. The annealed $Ti_{1-x}Co_xO_2$ thin films with $x{\leq}0.05$ showed a homogeneous structure without any clusters, and pure ferromagnetic properties of thin films are only attributed to the $Ti_{1-x}Co_xO_2$ (TCO) phases. On the other hand, in case of thin films above x=0.05, Co clusters formed in a homogeneous $Ti_{1-x}Co_xO_2$ Phase, and the overall ferromagnetic (FM) properties depended on both $FM_{TCO}$ and $FM_{Co}$. Co clusters with about 10nm-150nm size decreased the value of Mr (the remanent magnetization) and increased the saturation magnetic field.

• 한국세라믹학회지
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• 제40권1호
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• pp.62-68
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• 2003

졸-겔법으로 보자력 제어에 뛰어난 첨가제인 Co와 Ti을 첨가한 Ba-ferrite 미립자를 합성하였다. 졸-겔 반응시, 반응 시간이 90분에서 120분 이내에서 온도, pH 및 점도의 변화가 없고, aging 시간에 따라 점도가 안정한 상태치 졸을 얻을 수 있었다. 이 졸을 건조 및 열처리 후, Differential Thermal Analysis(DTA)와 X-Ray Diffractometer(XRD)를 통해 Ba-ferrite 상이 약 $700^{\circ}C$부터 생성됨을 확인하였으며, 열처리 온도 증가에 의해 결정성이 좋아짐을 볼 수 있었다. Scanning Election Microscopy(SEM)로 표면형상을 관찰한 결과 열처리 온도가 증가함에 따라 입자크기가 증가하였으며, 비교적 균질한 입도 분포의 미립자를 얻을 수 있었다. 또한, Vibrating Sample Magnetometer(VSM)로 Co와 Ti의 첨가량에 따른 자기적 특성을 관찰하였으며, 포화자화(M$_{s}$ )값은 첨가량에 관계없이 변화가 없었으나, 보자력(H$_{c}$)값은 첨가량에 따라 크게 변화하였다.

• 성인간호학회지
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• 제20권2호
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• pp.209-218
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• 2008

Purpose: Regarding the respiratory function of patients with an artificial airway, this study compared the effects between normal saline with chest vibration and normal saline with expectorant mixture, administered before endotracheal suction. Methods: The study was conducted in the ICUs of one university hospital located in Incheon. The experimental group I received normal saline with chest vibration administered before endotracheal suction while the experimental group II received normal saline with expectorant mixture administered before endotracheal suction. For respiratory function, $PaO_2$, $PaCO_2$, and $O_2$ saturation were measured by ABGA at 3 minutes after endotracheal suction for both pre-test and post-test. Results: The two groups were not different significantly regarding $PaO_2$ level and $O_2$ saturation after the treatments, while, the experimental group II had lower $PaCO_2$ level than the experimental group I after the treatments (t = 2.075, p = .042). For experimental group II, post-test score of $PaCO_2$ level was significantly lower than that of the pre-test score (t = 1.842, p = .075). Conclusion: The administration of normal saline with expectorant mixture before endotracheal suction reduced $PaCO_2$ level and improved the respiratory function.

• 대한음성학회:학술대회논문집
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• 대한음성학회 2007년도 한국음성과학회 공동학술대회 발표논문집
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• pp.261-264
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• 2007

Five males trained singers (age:25.0${\pm}$1.4years, career:6.8${\pm}$1.1 years) and five female trained singers (age:22.0${\pm}$1.0years, career:5.8${\pm}$1.2 years) participated in this study. SaO2(Oxi Hemoglobin saturation) measured by Oxy-Pulse meter and PAC02 (Pressure Alveolar Co2) measured by Quick et CO2 are compared with pre and post vocal training. As the result, PAC02 was lower than normal range (36-40mmHg) after vocal training, leading to Hypocapnia. This causes headache and dizziness

• 한국자기학회:학술대회 개요집
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• 한국자기학회 2011년도 임시총회 및 하계학술연구발표회
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• pp.19-19
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• 2011

We studied the effect of Dy content on the magnetic properties of cobalt ferrite single crystal. The $CoFe_{1.9}Dy_{0.1}O_4$ single crystals were grown by the flux method by using $Na_2B_4O_{7.}10H_2O$ (Borax) as a solvent (flux). The black and shiny single crystals were obtained as a product. The X-ray diffraction test at room temperature confirmed the spinel cubic symmetry with lattice constant a = $8.42{\AA}$ of the single crystals. The presences of constitute elements (Co, Fe and Dy) was endorsedby EDAX analysis. The saturation magnetization (Ms) of $CoFe_{1.9}Dy_{0.1}O_4$ single crystals was measured and is found to be 72emu/g or equivalently $3.2{\mu}B$/f.u. at 300 K. The observed Ms and coercivity (Hc) is found to be lower than that of pure $CoFe_2O_4$.

• 한국미생물·생명공학회지
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• 제25권3호
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• pp.235-239
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• 1997

Chlorococcum littorale has been grown in high $CO_2$ concentrations to utilize $CO_2$ gas in the polluted air. The effect of incident light intensity on the specific growth rate is expressed by a photoinhibition model, showing half- saturation constant, $K_0\;as\;8\;(W/m^2)$ and inhibition constant, Ki as 35 $(W/m^2)$. The maximum specific growth rate was also estimated as 0.095 (1/day) under this condition. This strain maintained the optimum growth rate in 20% of $CO_2$ gas but 50% of input $CO_2$ gas is the maximum concentration considering the economical efficiency. The maximum Specific $CO_2$ consumption rate, $qCO_2$ was measured as 17.48 (mg $CO_2/g$ dry wt./day) in batch cultivation, 11.2 (mg $CO_2/g$ dry wt./day) in fed-batch cultivation and 10.87 (mg $CO_2/g$ dry wt./day) at 0.065 (1/day) of dilution rate in continuous cultivation. The chemical composition of the biomass obtained from this process showed 32.5% of protein, 27.5% of lipid, 16.5% of carbohydrate and ash 11.7%.

• The Korean Journal of Physiology
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• 제20권1호
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• pp.53-63
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• 1986

과산화수소$(H_2O_2)$가 급성 일산화탄소(CO)중독의 회복에 미치는 영향을 알아보기 위하여 가토를 1% Corktm에 30분간 노출시킨후 자연회복군, 100%산소 흡입군 및 $H_2O_2$관장군(10ml/kg의 0.5% $H_2O_2$용액을 2ml내외의 사람혈액과 함께 관장)으로 나누어, 회복기 15,30,60 및 90분에 동맥혈의 $pH,\;PCO_2,\;CO_2$ 및 HbCO 포화도를 측정하여 다음과 같은 결론을 얻었다. pH는 급성 CO중독시 3개군 모두에서 감소하였고, 회복기에는 서서히 증가하여 자연회복군과 100%산소 흡입군은 회복기 90분에 거의 회복되나, $H_2O_2$관장군에서는 pH의 회복이 다른군보다 늦었다. $PaCO_2$는 급성 Co중독시 3개군 모두에서 감소하였고, 회복기에는 서서히 증가하였으나, 자연회복군의 $PaCO_2$는 회복기 90분에 거의 회복하는데 반하여 100%산소흡입군과 $H_2O_2$관장군의 $PaCO_2$는 회복이 늦었고 회복기 90분에도 완전히 회복되지 못하였다. $PaO_2$는 급성 Co중독시 약간 감소하였다가 회복기에는 회복기 15분부터 급격히 증가하였고 회복기 90분까지 대조치보다 높은 $PaO_2$를 유지하였다. 회복기동안 $H_2O_2$관장군의 $PaO_2$는 $102{\sim}107mmhg$로 자연회복군보다 약 10 mmhg 높은 수준을 보였다. HbCO 포화도는 급성 CO중독시 $54{\sim}72%$까지 증가하였다. 회복기에는 $H_2O_2$관장군의 HbCO 포화도의 회복이 자연회복군이나 100%산소 흡입군보다 빨랐으며, 100%산소 흡입군은 회복기 30분에서 60분사이에 자연회복군보다 더 빠른 회복을 보였다. 이상의 결과에서 0.5% $H_2O_2$관장은 CO중독시 혈액의 산소분압을 어느정도 증가시킬 뿐 아니라 혈색소와 결합된 CO의 해리를 촉진시켜, 단독요법 또는 산소요법과 병행하여 사용할 때 급성CO중독에 효과적인 치료법이 될 수 있을 것으로 사료된다.

• 한국자원식물학회지
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• 제26권5호
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• pp.636-644
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• 2013

원료곡인 동부의 침종, 포화, 노화 조건이 동부나물 생산량과 생장반응에 미치는 영향을 검토한 결과, 흡수량은 침종 초기 2시간까지는 급속히 증가하다 이후에는 완만히 증가하였으나, 발아력과 나물 생산수율 및 잔뿌리 발생량은 침종기간(1~6시간)이 길어질수록 낮았다. 5일간 포화(수분 $96{\pm}1%$, $20^{\circ}C$)처리가 무처리나 1, 3일간 포화처리에 비해 발아력과 나물 생산수율 및 잔뿌리 발생량이 높았다. 고온 노화처리에 따른 발아력과 나물 생산수율은 무처리에 비해 낮았는데, 이상의 결과로 동부나물 재배를 위한 원료곡 전처리 방법은 5일간 포화(수분 $96{\pm}1%$, $20^{\circ}C$)처리하고 세척하여 재배하는 것이 좋은 것으로 판단된다.

• Journal of Ginseng Research
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• 제36권4호
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• pp.461-468
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• 2012

In this study, photosynthetic parameters such as the net photosynthesis rate, stomatal conductance, intercellular $CO_2$ concentration, and transpiration rate were examined in selected ginseng varieties and/or lines that are resistant (Yunpoong, HTIR 1, HTIR 2, and HTIR 3) and susceptible (Chunpoong) to high temperature injury (HTI). The net photosynthesis rate increased with the increase in the light intensity in all the HTI-resistant and -susceptible ginseng lines with a light saturation point of $200\;{\mu}mol\;m^{-2}s^{-1}$, except for Yunpoong that had a light saturation point of $400\;{\mu}mol\;m^{-2}s^{-1}$. At the light saturation point, the net photosynthesis rate in July was highest in HTIR 3, at $4.2\;{\mu}mol\;CO_2\;m^{-2}s^{-1}$, and was lowest in Yunpoong, HTIR 1, Chunpoong, and HTIR 2, in that order, at 1.9 to $3.7\;{\mu}mol\;CO_2\;m^{-2}s^{-1}$. The net photosynthesis rate in August was highest in Yunpoong at $5.9\;{\mu}mol\;CO_2\;m^{-2}s^{-1}$, and lowest in HTIR 1 and HTIR 3 ($4.5\;{\mu}mol\;CO_2\;m^{-2}s^{-1}$) and in other lines, in that order, at 2.8 to $2.9\;{\mu}mol\;CO_2\;m^{-2}s^{-1}$. The stomatal conductance in July was highest in HTIR 3 (0.055 mol $H_2O\;m^{-2}s^{-1}$) and Yunpoong, Chunpoong, HTIR 1, and HTIR 2 were 0.038, 0.037, 0.031, and 0.017 in that orders. In August, meanwhile, HTIR 1 showed the highest as 0.075, and followed by HTIR 3, Chungpoong, and HTIR 2 with 0.070, 0.047, and 0.023, respectively. The intercellular $CO_2$ concentration at the light saturation point in July and August was much lower in HTIR 2 at 139 and $185\;{\mu}mol\;mol^{-1}$ than in the other ginseng lines at 217 to 257 and 274 to $287\;{\mu}mol\;mol^{-1}$, respectively. The transpiration rate in July and August was higher in the HTI-resistant lines of Yunpoong, HTIR 1, and/or HTIR 3 at 0.83 to 1.03 and 1.67 to 2.10 mol $H_2O\;m^{-2}s^{-1}$ than in the other ginseng lines at 0.27 to 0.79 mol $H_2O\;m^{-2}s^{-1}$ and 0.51-1.65 mol $H_2O\;m^{-2}s^{-1}$, respectively. Conclusively, all the photosynthetic parameters that were examined in this study were generally higher in the HTI-resistant ginseng lines than in the HTI-susceptible lines, except for HTIR 2, and were much higher in August than in July, especially in the resistant ginseng lines. All these results can be used to provide basic information for the selection of HTI-resistant ginseng lines and the application of cultural practices that are efficient for ginseng growth, based on the photosynthetic characteristics of the lines.

• 설비공학논문집
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• 제21권1호
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• pp.16-22
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• 2009

In order to investigate $CO_2$ heat transfer coefficient and pressure drop by PAG oil concentration during $CO_2$ evaporation, the experiment on evaporation heat transfer characteristics in a mini-channels were performed. The experimental apparatus consisted of a test section, a DC power supply, a heater, a chiller, a mass flow meter, a pump and a measurement system. Experiment was conducted for various mass fluxes($300{\sim}800kg/m^{2}s$), heat fluxes($10{\sim}40kW/m^2$) saturation temperatures($-5{\sim}5^{\circ}C$), and PAG oil concentration(0, 3, 5wt%). The variation of the heat transfer coefficient was different according to the oil concentration. With the increase of the oil concentration, the evaporation heat transfer coefficient decreased and the delay of dryout by oil addition was found. Pressure drop increased with the increase of the oil concentration and heat flux, and the decrease of saturation temperature.