• Proceedings of the Korean Vacuum Society Conference
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• 2012.02a
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• pp.458-458
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• 2012

Fuel Cell is used stacking metal or polymer substrate. This hydro property of substrate surface is very important. Usually, surface property is hydrophilic. The surface oxidation of SUS is investigated through plasma treatments with an atmospheric-pressure dielectric barrier discharge (DBD) for increasing hydrophilic property. The plasma process makes an experiment under various operating conditions of the DBD, which operating conditions are treatment time, plasma gas mixture ratio, the plasma source supply frequency. Two kinds of SUS substrate, SUS-304 and SUS 316L, were used. Discharge frequency has a crucial impact on equipment performance and gas treatment. After the plasma treatment of a SUS plate, highly improved wettability was noted. But, when high oxygen supply, the substrate damaged seriously.

• Journal of the Society of Disaster Information
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• v.18 no.1
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• pp.1-9
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• 2022

Purpose: In this study, we used hydrophilic waterstop used in geosynthetics vertical barrier system to evaluate the performance of impermeability under sealing conditions. Method: ASTM D5887 and ASTM D6766 were applied to determine the capability of the connection during the geosynthetics vertical barrier system. Hydrophilic waterstop was saturated in each solution and the weight, thickness, and volume changes were analyzed over elapsed time. Hydrophilic waterstop was installed at the geosynthetics vertical barrier system connection to evaluate the permeability characteristics. Results: As the expansion reaction time of hydrophilic waterstop increased relatively under saline conditions, the decrease in permeability also showed a smaller decrease in fresh water. Furthermore, the method of engagement of the geosynthetics vertical barrier system showed somewhat better performance of the impermeability due to the large pressure resistance caused by the roll joint type than interlock type. Conclusion: In urban pollutants, which can estimate the outflow of pollutants such as oil storage facilities and industrial complexes, proactive response technologies that can prevent the contaminant diffusion can significantly reduce the damage.

• Korean Journal of Materials Research
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• v.33 no.4
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• pp.115-123
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• 2023

In this paper, we report and discuss the semi-permanently hydrophilic (SPH) treatment of polyester fabric using plasma polymerization and oxidation based on atmospheric pressure dielectric barrier discharge (APDBD) technology. SiO_xC_y(-H) was coated on polyester fabric using Hexamethylcyclotrisiloxane (HMCTSO) as a precursor, and then plasma oxidation was performed to change the upper layer of the thin film to SiO₂-like. The degradation of hydrophilicity of the SPH polyester fabrics was evaluated by water contact angle (WCA) and wicking time after repeated washing. The surface morphology of the coated yarns was observed with scanning electron microscopy, and the presence of the coating layer was confirmed by measuring the Si peak using energy dispersive x-ray spectroscopy. The WCA of the SPH polyester fabric increased to 50 degrees after 30 washes, but it was still hydrophilic compared to the untreated fabric. The decrease in hydrophilicity of the SPH fabric was due to peeling of the SiO_xC_y(-H) thin film coated on polyester yarns.

• Korean Journal of Materials Research
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• v.16 no.9
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• pp.543-549
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• 2006

Polyimides (PI) are treated with $He/O_2$ and $He/O_2/NF_3$ atmospheric pressure rf dielectric barrier discharge in order to investigate the roles of $NF_3$ that is one of the PI etching gases. Surface changes are analyzed by x-ray photoelectron spectroscopy (XPS), atomic force microscopy (AFM), and contact angle measurement. The surface roughness of PI and the ratio of C=O, which is hydrophilic functional group, is more increased by $He/O_2/NF_3$ discharge than by $He/O_2$ discharge. The C=O species on the PI surface is increased up to 30 percent with rf power. The surface roughness of PI is increased from 0.4 to 11 nm with rf power. The water drop contact angles on PI, however, are reduced from $65^{\circ}\;to\;9^{\circ}$ by plasma treatment independently of $NF_3$.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.18 no.2
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• pp.148-152
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• 2005

Atmospheric low-temperature plasma was produced using dielectric barrier discharge (DBD) plate-type plasma reactor and high frequency of 13.56 Hz. The surfaces of polyimide films for insulating and packaging materials were treated by the atmospheric low-temperature plasma. The contact angle of 67$^{\circ}$ was observed before the plasma treatment. The contact angle was decreased with deceasing the velocity of plasma treatment. In case of oxygen content of 0.2 %, electrode gap of 2 mm, the velocity of plasma treatment of 20 mm/sec, and input power of 400 W, the minimum contact angle of 13$^{\circ}$ was observed. The chemical characteristics of polyimide film after the plama treatment were investigated using X-ray photoelectron spectroscopy (XPS), and new carboxyl group bond was observed. The surfaces of polyimide films were changed into hydrophilic by the atmospheric low-temperature plasma. The polyimide films having hydrophilic surface will be very useful as a packaging and insulating materials in electronic devices.

• YAKHAK HOEJI
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• v.42 no.2
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• pp.196-204
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• 1998

The blood-brain barrier (BBB) of rats was modificated opening reversibly by infusing a hyperosmotic solution of arabinose (1.6 molal) into the right external carotid artery. Pre vious studies demonstrated that permeability was increased maxmmally in the first 15 min and remained slightly elevated at 1 hr. As control reference, saline was used. In the present study, to evaluate the effects of osmotic BBB opening on the BBB trasport according to hydrophilic or hydrophobic characteristics of drugs. And the differences of the uptakes of these compounds to right (treated osmotic opening) and left (untreated) hemispheres in same rats were compared each other following injection of 8 mCi per rat of $^{99m}Tc$-ethylene triamine pentaacetic acid (DTPA) as hydrophilic drug or 5mg/kg of phenytoin as hydrophobic drug mto the right external carotid artery of rats between two groups (1.6 molal arabinose vs saline). The uptakes of $^{99m}Tc$-DTPA and phenytoin in the right cerebral hemispheres were increased to about thirty three times and twice rather than those in the left cerebral heimspheres, respectively. And PAs (permeability X capillary surface area) were also increased from a control mean of 2.11${\times}10^{-4}$ (Untreated) to 6.98${\times}10^{-3}\;sec^{-1}$ (treated osmotic opening for $^{99m}Tc$-DTPA and 0.29 to 0.17 $sec^{-1}$ for phenytoin, respectively. From the results of present study, it is noted that osmotic opening of BBB is more effective in the brain delivery of hydrophilic drugs rather than that of hydrophobic drugs.

• Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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• v.23 no.12
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• pp.184-190
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• 2009

Tri-acetyl-cellulose(TAC) film surface was modified by atmospheric-pressure plasma technique to obtain the hydrophilic functional groups and improve the contact angle. TAC film was modified with N2 plasma ionized in dielectric barrier discharge(DBD) reactor under atmospheric pressure. We measured the change of the contact angle and the surface energy with respect to the plasma treatment conditions such as plasma treatment power, discharge gap and Ｎ2 gas flow rate. As the plasma treatment speed of 100[mm/sec], the plasma treatment power of 1.5[kW], discharge gap 2[mm] and the $N_2$ gas flow rate 140[LPM], the best contact angle and the highest surface energy were obtained. The degree of hydrophilization depended strongly on the plasma-treating time and discharge power.

• KOREAN JOURNAL OF PACKAGING SCIENCE & TECHNOLOGY
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• v.15 no.3
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• pp.99-104
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• 2009

Soy protein isolate (SPI)-based nanocomposite films with three different types of nanoclays, such as Cloisite $Na^+$, Cloisite 20A, and Cloisite 30B, were prepared using a solution casting method, and their optical, tensile, and water vapor barrier properties were determined to investigate the effect of nano-clay type on film properties. Among the tested nanoclays, Cloisite $Na^+$, a hydrophilic montmorillonite (MMT), exhibited the highest transparency with least opaqueness, the highest tensile strength, and the highest water vapor barrier properties, indicating Cloisite $Na^+$ is the most compatible with SPI polymer matrix to form nanocomposite films. The film properties of SPI/Cloisite $Na^+$ nanocomposite films were strongly dependent on the concentration of the clay. Film properties such as optical, tensile, and water vapor barrier properties improved significantly (p<0.05) as the concentration of clay increased. However, the effectiveness of addition of the clay reduced above a certain level (i.e., 5wt%), indicating that there is an optimum amount of clay addition to exploit the full advantage of nanocmposite films.

• Journal of the korean veterinary medical association
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• v.47 no.1
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• pp.42-46
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• 2011

임상에 있어 눈에 적용하는 약물의 적용은 정상적인 조직을 손상시키지 않으면서 원하는 안구 조직에 목표로 하는 용량의 안약을 전달하는 것이 목적이라고 할 수 있다. 그러나 이러한 간단한 목적도 실제로 환자의 성격, 안구 조직의 민감성, 그리고 친지질성 각막 외피세포(lipophilic corneal epithelium), 친수성 각막 그리고 공막의 간질층(hydrophilic corneal and sclera stroma), 결막의 임파 조직, 맥락막의 혈관 등, Blood-ocular barrier등 안구의 조직 자체의 장벽들로 인해 어려움을 내포하고 있는 것 역시 사실이다. 평소에 처방하고 있는 안약들을 조금 더 효과적으로 전달하기 위해 필요한 눈에 대한 이해에 대해 다루어 보도록 한다.

• Proceedings of the PSK Conference
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• 2002.10a
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• pp.416.2-416.2
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• 2002

Transfersomes are highly detormable hydrophilic lipid vesicles that are able to penetrate the skin barrier so that they can be used to carry low- and high-molecular weight molecules into the body. Until recently. it has been reported that molecules such as insulin. interleukin-2 and several other large molecules have been transported into the body using Transfersomes as a delivery system. Here however, for the very first time, genes (GFP) have been transported into the mice non-invasively using the Transtersomes as a delivery vehicle. (omitted)