• The Korean Journal of Physiology
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• 제26권1호
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• pp.37-44
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• 1992

The encapsulation of the Purified bovine hemoglobin with Phospholipids obtained from egg folk was performed using a rotary vacuum evaporator. The prepared Hb-containing liposome (hemosome) had good properties as artificial red blood cell. The shape and size of the hemosomes were measured by a phase contrast microscope and image analyzer. The function of the hemosome as oxygen carrier was tested by measuring oxygen saturation curve with blood gas analyzer and infusing it into rats. The prepared hemosome was 1.184 + 0.423 ${\mu}m$ in diameter and round in shape. $P_{50}$ value of the hemosome solution was 28 mmHg. The synthesized red cells seem to function as oxygen carrier, because the severely bled rats were prolonged in their life by transfusion of the hemosome solution containing bovine hemoglobin.

• 대한기계학회논문집A
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• 제28권8호
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• pp.1159-1165
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• 2004

This paper describes fabrication of a micro cell counter integrated with an oxygen micropump and counting experiment with Sephadex G-25 beads ($70{\sim}100\;{\mu}m$). The pumping part consisted of a microheater, catalyst (manganese dioxide) enveloped with paraffin, hydrogen peroxide, and microchannel, and the counting part consisted of collimated light, a microwindow, and a phototransistor including an external circuit. The micropump generated oxygen gas by decomposing hydrogen peroxide with manganese dioxide, which was initiated by melting the paraffin with the microheater, and pumped beads in the microchannel. When the beads passed the microwindow, they shaded the collimated light and changed the illumination on the phototransistor, which caused the current variation in the circuit. The signals, according to the bead size, reached up to 22 mV with noise level of 2 mV during 50 seconds and the numbers of peaks were analyzed by magnitude.

• Journal of Electrical Engineering and Technology
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• 제7권6호
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• pp.983-989
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• 2012

The purpose of this paper is to decide the optimum synthesis conditions of polycrystalline diamond films according to the ratio of gas mixture. Diamond films were deposited with cyclo-hexane as a carbon precursor by the microwave plasma enhanced chemical vapor deposition process. The optimum oxygen ratio to cyclo-hexane was reached about 125 % under the fixed 0.3% c-hexane in hydrogen. Oxygen plays a role in etching the graphitic components of carbon sp2 bond effectively. By OES measurement, the best synthesis conditions found out about 12.5 % and 15.75 %, which is the emission intensity ratios of CH(B-X) and $H{\beta}$ on $H{\alpha}$, respectively. Also, the electron temperature was similar about 5,000 to 5,200 K in this work.

• 한국분말야금학회:학술대회논문집
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• 한국분말야금학회 2006년도 Extended Abstracts of 2006 POWDER METALLURGY World Congress Part 1
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• pp.416-417
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• 2006

Nanostructured ceria powder was synthesized by a thermochemical process and investigated its applicability for an oxygen gas sensor. An amorphous precursor powders prepared by spray drying a cerium-nitrate solution were transformed successfully into nanostructured ceria by heat-treatment in air atmosphere. The powders were a loose agglomerated structure with extremely fine $CeO_2$ particles about 15 nm in size, resulting in a very high specific surface area $(110\;m^2/g)$. The oxygen sensitivity and the response time $t_{90}$ measured at sintered sample at $1000^{\circ}C$ was about -0.25 and very short, i.e., $3{\sim}5$ seconds, respectively.

• Journal of Advanced Marine Engineering and Technology
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• 제26권6호
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• pp.679-687
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• 2002

In this study, a cycle simulation using a two-zone model is carried out to investigate the effect of intake charging conditions such as oxygen concentration, temperature and pressure on NO emissions in a DI diesel engine. The model is validated against measurements in terms of cylinder pressure, torque, BSFC and NOx emissions with 2902 cc DI diesel engine. Calculated results can be summarized as follows. The oxygen concentration in the intake charge is decreased with increasing of EGR rate and equivalence ratio. As the intake oxygen concentration is reduced, the combustion pressure and the burned gas temperature decrease and, as a result, NO formation decreases. Also, the results show that as the intake pressure increases and the intake temperature decreases, NO emissions are effectively reduced.

• 멤브레인
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• 제4권1호
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• pp.9-29
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• 1994

The development of separation technology is an important research subject as is clear from its role in the Japanese government's research and development program for basic technology for the next generation(1981~1990). Japan is poor not only in mineral resources but also in energy resources and if a sudden change occurs in oil producing facility or an accident occurs in a nuclear power plant, then energy policy must undergo changes and economic foundations may collapse. Japan has already experienced this. Although, oil prices are stable at present and Japan can import oil at low cost due to the yen appreciation, Japan needs to promote development work for any new energy crisis that may come in the future. This has been the motive for gas separation membrane development in Japan. The study of gas permeation through polymer membranes, which is the basis for membranes for gas separation, at Japanese universities began many years ago, but interest in membranes for gas separation was aroused mainly by the Government. The development of gas separation membranes in Japan started with membranes for oxygen separation on an industrial scale.

• Advances in materials Research
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• 제6권4호
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• pp.343-348
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• 2017

High-pressure gas atomization was employed to prepare the Fe-based $Fe_{50}Cr_{24}Mo_{21}Si_2B_3$ alloy powder. The effect of flow rate of atomizing gas on the median powder diameter was studied. The results show that the powder size decreased with increasing the flow rate of atomizing gas. Fe-based alloy coatings with amorphous phase fraction was then prepared by high velocity oxygen fuel spraying (HVOF) of gas atomized $Fe_{50}Cr_{24}Mo_{21}Si_2B_3$ powder. Microstructural studies show that the coatings present dense layered structure and low porosity of 0.17% in about $200{\mu}m$ thickness. The Fe-based alloy coating exhibits an average hardness of about 1230 HV. Our results show that the HVOF process results in dense and well-bonded coatings, making it attractive for protective coatings applications.

• 한국수소및신에너지학회논문집
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• 제25권1호
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• pp.87-96
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• 2014

Direct combustion characteristics of coal and oxygen carrier were measured in the thermogravimetric analyzer using four coals and two different oxygen carriers. The direct combustion efficiency decreased in order of Roto, Kideco, Sunhwa and Hyper coal for both oxygen carriers. Moreover, OCN703-1100 oxygen carrier showed better combustion efficiency than OCN706-1100 oxygen carrier for all four coals. The reduction characteristics of two oxygen carriers for $CH_4$, CO and $H_2$ gases were measured in the thermogravimetric analyzer to investigate why OCN703-1100 oxygen carrier showed better combustion efficiency than OCN706-1100 for all coals. The OCN703-1100 oxygen carrier represented higher reduction rate than OCN706-1100 for all reducing gases. Moreover, the total pore area and the porosity of OCN703-1100 were higher than those of OCN706-1100 oxygen carrier. The total volatile gas and volatile components of four coals were measured in a batch type fluidized bed reactor to investigate why the direct combustion efficiency decreased in order of Roto, Kideco, Sunhwa and Hyper coal for both oxygen carriers. The direct combustion efficiency was proportional to the total amount of ($CH_4+CO+H_2$) produced during devolatilization of coals.

• 순환기질환의공학회:학술대회논문집
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• 순환기질환의공학회 2005년도 제5회 학술대회 초록집
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• pp.21-22
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• 2005

• 한국진공학회:학술대회논문집
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• 한국진공학회 1997년도 제12회 학술발표회 논문개요집
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• pp.104-104
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• 1997