• 한국광학회:학술대회논문집
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• 한국광학회 1991년도 제6회 파동 및 레이저 학술발표회 Prodeedings of 6th Conference on Waves and Lasers
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• pp.64-64
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• 1991

The interaction of high-intensity, focused, nanosecond laser light with matter results in the production of high-temperature plasma, which in turn emits an intense pulse of x rays. The x-ray spectrum consists of strong line components of several keV photon energy and broad continuum. Such an x-ray source provides many advantages over conventional ones for many applications. Pulse nature of the x-ray emission is well-suited for studying transient phenomena and for imaging living biological specimen. Recent experiments have also shown that the laser plasma x ray may be used for x ray lithography. These studies and other applications will be discussed in detail.

• 한국독성학회:학술대회논문집
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• 한국독성학회 2002년도 Current Trends in Toxicological Sciences
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• pp.93-93
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• 2002

Oxidative stress has been associated with a number of diseases in humans. Among the sources that can generate oxidative stress, it has been reported that iron can generate reactive oxygen species (ROS) with thiol. In iron overload state, increased thiol levels in plasma appeared to be associated with human mortality.(omitted)

• 한국식품위생안전성학회:학술대회논문집
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• 한국식품위생안전성학회 2002년도 춘계학술발표대회 및 심포지움
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• pp.138-138
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• 2002

Oxidative stress has been associated with a number of diseases in human. Among the sources that can generate oxidative stress, it has been reported that iron can generate reactive oxygen species (ROS)with thiol. In iron overload state, increased thiol levels in plasma appeared to be associated with human mortality. In this study we examined whether iron could interact with thiols in plasma, generating ROS. In human plasma, unlike with Fe(III), Fe(II) increased lucigenin-enhanced chemiluminescence in concentration-dependent manner, and this was inhibited by SOD. Boiling of plasma did not affect chemiluminescence induced by Fe(II). Hovever, thiol depletion in plasma by pretreatment with N-ethylmaleimide (NEM)decreased Fe(II)-induced chemiluminescence significantly, suggesting that Fe(II) generated superoxide anion by the nonenzymatic reaction with plasma thiol. Consistent with this findings, albumin, the major thiol contributor in plasma, also generated ROS with Fe(II) and this generation was inhibited by pretreatment with NEM. Treatment with Fe(II) to plasma resulted un significant reduction of oxygen radical absorbance capacity (ORAC) value, suggest that total antioxidant capacity could diminished in iron overload state. In conclusion, In iron overload state, plasma may be affected by oxidative stress mediated by nonenzymatic reaction of Fe (II)with plasma thiol.

• 대한전기학회:학술대회논문집
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• 대한전기학회 1984년도 하계학술회의논문집
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• pp.292-293
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• 1984

• 한국유체기계학회 논문집
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• 제15권3호
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• pp.46-50
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• 2012

Plasma actuator makes parallel flow on the wall surface by the interaction between plasma and neutral air particles. Dielectric barrier discharge (DBD) plasma actuator is widely studied as one type of plasma actuators, which consists of one electrode exposed to the environmental gas and the other encapsulated by a dielectric material. This paper is experimentally focused on the performance of DBD plasma actuator mounted on a flat plate, which depends on kinds of the electrode materials, their thicknesses and the supplied voltage including its frequency. We measured the velocity magnitudes of the induced flow by a stagnation probe as a performance parameter of the plasma actuators. The velocity profiles of the flow induced by the plasma actuators are similar in all measurement cases. The magnitude of the induced velocity is strongly influenced by the thickness of the electrodes and the frequency of the input voltage. The performance of DBD plasma actuators is related to the electric properties of the electrode materials such as the ionization energy and the electrical resistivity.

• Journal of Astronomy and Space Sciences
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• 제7권2호
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• pp.113-123
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• 1990

전자 beam이 중성 plasma계에 들어왔을 때의 상호작용을 이차원 정전 model을 사용하여 수치계산을 한 결과 beam의 밀도변화에 따라 상호작용이 큰 변화를 보이는 것으로 나타났다. beam 전자의 밀도가 주변 전자의 밀도보다 낮을 때는 많은 양의 beam들이 주변 plasma와의 상호작용을 통해 위상공간에서 vortex 구조를 보이며 입사지역으로부터 멀리 진행할 수 있었던 반면 beam 전자들의 밀도가 높을 때는 대부분의 beam 전자들이 입사지역으로 되돌아오는 희귀전류를 형성하였다. 이 때 자기장의 게기에 따라 전자보다 훨씬 질랴이 큰 ion들이 가속될 수도 있으며 전자들의 전파와 상호작용의 양상이 크게 바뀔 수 있는 것으로 나타났다.

• Archives of Pharmacal Research
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• 제15권3호
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• pp.246-250
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• 1992

Acetaminophen (AAP) and ranitidine (RT) were coadministered orally to nine rats, and the possible contribution of the gastric emptying to the plasma concentration profiles of them was examined. The drugs showed multiple plasma peaks similar to the respective ones after separated administration of each durg. IT Implies that there is no significant interaction between AAP and RT in terms of the gastric emptying or drug absorption. There were no significant linear correlations of the peak patterns (peak height and peak time) between AAP andd RT. It is contrary to the expectation from the biphasic gastric emptying (BGE) theory previously suggested for AAP and RT. The BGE theory. Therefore, seemed to have some draw-backs in explaining satisfactorily the multiple plasma peaks of AAP and RT. Two more doubts raised previously against the BGE theory were also discussed.

• 대한기계학회:학술대회논문집
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• 대한기계학회 2007년도 춘계학술대회B
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• pp.2506-2511
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• 2007

The coupled simulation is performed to find out the interaction of arc plasmas with surrounding materials in a thermal puffer plasma chamber. In order to be more realistic, PTFE nozzle ablation and Cu electrode evaporation, which are caused by high temperature of arc plasmas, are considered together. Pressure rise and temperature inside the chamber generated during the whole arcing history are investigated with the applied currents. It is very important to define how thermal flow and mass transfer are processing between the arc plasma and surrounding materials for further understanding complex physics inside the chamber. It is concluded that the result might be very useful to understand the mechanism happened inside and to design thermal puffer plasma chambers, but further experimental studies are required to verify the results for the more practical applications.

• 한국공작기계학회논문집
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• 제17권1호
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• pp.98-105
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• 2008

In this paper, the system for monitoring process of aluminum laser welding was developed using the light signal emitted from the plasma which comes from interaction between material and laser. Photodiode for monitoring system was selected based on the spectrum analysis of light from plasma and keyhole. Behavior of plasma and keyhole was analyzed through the sensor signals. Value of sensor signal represented the light intensity and fluctuation of signal indicated the stability of plasma and keyhole. For the relation between welding condition and sensor signals, the input power and weld geometry greatly effected on the average of each sensor signals. Using the feature values of signals, estimation model for tensile strength of weld was formulated with neural network algorithm. Performance of this model was verified through coefficient of determination and average error rate.

• 약학회지
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• 제44권3호
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• pp.251-256
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• 2000

Sterically stabilized liposomes (SSL) composed of distearoylphosphatidylcholine, cholesterol, dicetylphosphate and distearoylphosphatiodylethanolamine-N-poly(ethyleneglycol) 2000 (DSPE-PEG 2000) were made by reverse phase evaporation method to prolong biological half-life and decrease toxic side effect of drug. Streptozocin (572), a water-soluble antitumor agent with short half-life, was selected as a model drug. The size of SSL was controlled by polycarbonate extrusion to 100 nm which is adequate size for long circulation in plasma. The release rate of drugs from SSL in PBS was evaluated. And the stability of STZ-containing liposomes against drug leakage into rat plasma was evaluated in order to investigate the interaction of liposome and plasma protein. Incorporation of DSPE-PEG 2000 into conventional liposomes significantly decreased the drug leakage into rat plasma.