• Title/Summary/Keyword: Water plasma

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The Effects of Water Addition on the Color and Crystalline Phase of Y2O3 Coatings Fabricated by Plasma Suspension Spray

  • Park, Sang-Jun;Lee, Jung-Ki;Oh, Yoon-Suk;Kim, Seongwon;Kim, Hyungsun;Lee, Sung-Min
    • Journal of the Korean Ceramic Society
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    • v.53 no.6
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    • pp.641-646
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    • 2016
  • The effects of water addition on $Y_2O_3$ coatings or thick films prepared by plasma suspension spray (SPS) have been investigated. Water addition in suspension media was found to be effective to control the color of a $Y_2O_3$ coating prepared by SPS. The color changed with water addition at the shortest stand-off distance of 50 mm even if samples had the same crystalline phase. Change was not correlated with fragmentation behavior of liquid suspension inside the plasma jet. Water content over 50 vol% was found to produce unmelted particles, indicating that water suppressed heat transfer to the particles. However, plasma jet temperature was not affected. Instead, the coating fabricated with water addition has higher oxygen and lower carbon content compared to these characteristics of the coating without water addition. This was attributed to the retarded complete evaporation of liquid media from the suspension droplet, resulting in inhibition of excessive heating and evaporation of the molten $Y_2O_3$ droplet. In this regard, crystalline phase development with respect to stand-off distance and water addition was discussed.

Change in plasma cortisol and glucose levels of Oncorhynchus keta according to water temperature

  • Young Seok Seo;Hyo Bin Lee;Joo Hak Jeong;Seong Jun Mun;Han Kyu Lim
    • Fisheries and Aquatic Sciences
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    • v.26 no.2
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    • pp.117-132
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    • 2023
  • Chum salmon (Oncorhynchus keta) is a species of anadromous salmonid inhabiting coastal rivers in the North Pacific and the Arctic in the Bering and is the most widely distributed among Pacific salmon species. It is an important fish species in Korea as the salmon releasing project is being actively carried out. This study was conducted to investigate changes in the physiological activity of O. keta according to water temperature. Three experiments were conducted according to the water temperature and period, and the plasma concentrations of cortisol and glucose were analyzed from the blood samples of the experimental groups. Experiment I is a short-term water temperature experiment, in which water temperature stimulation was given for 4 hours at water temperatures of 12℃, 16℃ (control), 20℃, and 24℃, and a recovery period was given for 4 hours. Experiment II is an experiment in which water temperature stimulation was given for 24 hours, 48 hours, and 72 hours at a high temperature of 24℃, and a recovery period was given for 12 hours, respectively. Experiment III is a long-term water temperature experiment, in which the water temperature was 12℃, 16℃ (control), 20℃, and 24℃ for 8 weeks. As a result of the experiment, in Experiment I, there was no significant difference in the survival rate between the experimental groups, but the concentration of cortisol and glucose in the plasma according to the set water temperature showed a significant difference. In Experiment II, there was no significant trend according to the maintenance time of the high-temperature state, but as the temperature increased, the plasma cortisol and glucose levels significantly increased compared to the control group. In Experiment III, all of the experimental group C (24℃) died in the 1st week, and there was no significant difference in the plasma glucose at the 1st and 8th weeks among the remaining experimental groups.

Wettability and Water Repellency of Polyester Fabrics Treated by Low Temperture Plasma (저온플라즈마처리에 의한 폴리에스테르직물의 흡수성 및 발수성 변화)

  • 권영아
    • Journal of the Korean Society of Clothing and Textiles
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    • v.19 no.2
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    • pp.317-328
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    • 1995
  • The objective of this study was to determine the effects of low temperature plasma on the surface properties of polyester fabric with respect to wettability and water repellency. Highly wettable polyester fabric surfaces were obtained by oxygen treatment. The improved wettabililty of oxygen plasma treated fabrics decreased with aging time up to 30 days, and then the wettability remained relatively constant and still exhibited significant improvement compared to that of untreated polyester. Water repellency was significantly improved by tetratfluorocarbon plasma treatment. Such an improvement appears due to introduced fluo\ulcornerrine atoms or a thin fluorocarbon film on the fiber surface. Water repellency remained constant in fact, even after 150 days.

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Effect of Polyporus umbellatus Fries on the Renal Function of Dog (저분(猪芬)의 개의 신장기능(腎臟機能)에 미치는 영향(影響))

  • Kang, Hyung-Yong;Ko, Suk-Tai
    • Journal of Pharmaceutical Investigation
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    • v.5 no.1
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    • pp.28-40
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    • 1975
  • Polyporus would used as diuretics. Then, for the purpose of experimentally certifying the above mention, the effect on the renal function of dog was investigated, utilizing clearance technique. Water and alcohol extracts, when injected intravenously, produced significant increases of urinary sodium and potassium, osmolar and free water clearances, and urine flow, while glomerular filtration rate and renal plasma flow remained unchanged. During diuresis produced by furosemide, addition of water extract reduced the action of furosemide and markedly renal plasma flow. It would appear that these compounds are capable of action by a different mechanism or a different site. water extract, when infused directly into a renal artery, reduced the urine flow of experimental kidney as well as renal plasma flow, and the contralateral kidney exhibited diuresis, whereas amounts of sodium and potassium excreted in urine increased on both kidney. It is surmised from those observations that Polyporus induces diuresis by inhibition the reabsorptive mechanism of renal tubules through some endogeneous humoral substances, in addition, directly reduces the renal plasma flow.

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Effect of Gastrodiae Rhizoma Extract on Blood Pressure and Plasma Catecholamine Level in Unanaesthetized Spontaneously Hypertensive Rats (천마(天麻)엑기스가 Spontaneously Hypertensive Rat 에서 혈압(血壓) 및 혈장(血漿) Catecholamine 함량의 변화(變化)에 미치는 영향(影響))

  • Yang, Chae-Ha;Kwen, Yong-Zun;Kim, Mi-Ryeo
    • The Journal of Korean Medicine
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    • v.16 no.2 s.30
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    • pp.433-446
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    • 1995
  • The present study was carried out to investigate the effect of water extract and 70% ethanol extract from Gastrodiae Rhizoma on cardiovascular activities and plasma levels of catecholamines in unanaesthetized spontaneously hypertensive rats. The depressor response in SHR was observed during three to six hour period after an oral administration of water extract from Gastrodiae Rhizoma(GR). There was a statistically significant correlation between the magnitude of the depressor response induced by an oral administration of water extract from GR and the initial control blood pressure level. The increase in blood pressure induced by norepinephrine was less in Wistar rat treated with GR water extract than those without GR extract. No significant change in heart rate was observed in SHR receiving either water extract or ethanol extract from GR. Associated with the depressor response, there was a concomitant reduction in plasma levels of norepinephrine in SHR at 4 hour after an oral administration of water extract from GR. Plasma levels of norepinephrine and epinephrine were decreased slightly at 2 hour after an oral administration of ethanol extract from GR. These results suggest that the depressor effect of water extract from GR may be due, in part, to a decreased sympathoadrenal activity.

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Surface Modification of Polypropylene Fiber by Plasma Discharge (방전처리에 의한 Polypropylene섬유의 표면개질)

  • 허만우;이창재;강인규;한명호;김삼수;임학상
    • Textile Coloration and Finishing
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    • v.11 no.2
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    • pp.27-37
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    • 1999
  • Polypropylene(PP) films were treated with plasma glow discharge to produce peroxy radicals on the surfaces. The peroxy radicals formed on the PP film surfaces were subsequently used for the graft polymerization of acrylic acid and acrylamide in an aqueous solution by heating, respectively. Introduction of acrylic acid and acrylamide on the PP film could be confirmed by the observation of carbonyl and primary amine absorptions based on carboxylic acid and amide, respectively. And introduction of functional group could be confirmed by weight analysis and ESCA. The water contact angle(90$^{\circ}$) of PP film was constant, irrespective of elapsed time, while plasma-treated and functional monomer-grafted PP films were slowly increased with elapsed time, showing the rearrangement of surface polar groups in air condition. The water contact angle$(90^\circ)$ of PP film was decreased by the plasma treatment$(56^\circ)$ and further decreased by the grafting of acrylic acid$(34^\circ)$ and acrylamide$(37^\circ)$, indicating increased hydrophilicity of the modified surfaces. The water contact angle of plasma-treated PP film increased a little as time elapsing. The half-life periods of surface voltage on acrylic acid-(31sec) and acrylamide-grafted PP(42sec) were significantly decreased when compared to those on PP(950sec) and plasma-treated PP film(241sec). In the experiments using acid, basic and disperse dyes, absorbance and $\Delta{E}$ values of functional monomer-grafted PP films were significantly increased than that of oxygen plasma-treated one.

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Measurement of Hydroxyl Radical Density at Bio-Solutions Generated from the Atmospheric Pressure Non-Thermal Plasma Jet

  • Kim, Yong Hee;Hong, Young June;Uhm, Han Sub;Choi, Eun Ha
    • Proceedings of the Korean Vacuum Society Conference
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    • 2013.02a
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    • pp.494-494
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    • 2013
  • Atmospheric pressure non-thermal plasma of the needle-typed interaction with aqueous solutions has received increasing attention for their biomedical applications [1]. In this context, surface discharges at bio-solutions were investigated experimentally. We have generated the non-thermal plasma jet bombarding the bio-solution surface by using an Ar gas flow and investigated the emission lines by OES (optical emission spectroscopy) [2]. Moreover, The non-thermal plasma interaction with bio-solutions has received increasing attention for their biomedical applications. So we researched, the OH radical density of various biological solutions in the surface by non-thermal plasma were investigated by Ar gases. The OH radical density of DI water; deionized water, DMEM Dulbecco's modified eagle medium, and PBS; 1x phosphate buffered saline by non-thermal plasma jet. It is noted that the OH radical density of DI water and DMEM are measured to be about $4.33{\times}1016cm-3$ and $2.18{\times}1016cm-3$, respectively, under Ar gas flow 250 sccm (standard cubic centimeter per minute) in this experiment. The OH radical density of buffer solution such as PBS has also been investigated and measured to be value of about $2.18{\times}1016cm-3$ by the ultraviolet optical absorption spectroscopy.

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Pathophysiology and management of disorders in water metabolism (수분 대사 장애 질환의 병태 생리와 치료)

  • Kim, Dong Un
    • Clinical and Experimental Pediatrics
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    • v.50 no.5
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    • pp.430-435
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    • 2007
  • Even though we drink and excrete water without recognition, the amount and the composition of body fluid remain constant everyday. Maintenance of a normal osmolality is under the control of water balance which is regulated by vasopressin despite sodium concentration is the dominant determinant of plasma osmolality. The increased plasma osmolality (hypernatremia) can be normalized by the concentration of urine, which is the other way of gaining free water than drinking water, while the low plasma osmolality (hyponatremia) can be normalized by the dilution of urine which is the only regulated way of free water excretion. On the other hand, volume status depends on the control of sodium balance which is regulated mainly by renin-angiotensin-aldosterone system, through which volume depletion can be restored by enhancing sodium retention and concomitant water reabsorption. This review focuses on the urine concentration and dilution mechanism mediated by vasopressin and the associated disorders; diabetes insipidus and syndrome of inappropriate antidiuretic hormone secretion.

Synthesis of N-doped Ethylcyclohexane Plasma Polymer Thin Films with Controlled Ammonia Flow Rate by PECVD Method

  • Seo, Hyunjin;Cho, Sang-Jin;Boo, Jin-Hyo
    • Applied Science and Convergence Technology
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    • v.23 no.1
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    • pp.44-47
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    • 2014
  • In this study, we investigated the basic properties of N-doped ethylcyclohexene plasma polymer thin films that deposited by radio frequency (13.56 MHz) plasma-enhanced chemical vapor deposition (PECVD) method with controlled ammonia flow rate. Ethylcyclohexene was used as organic precursor with hydrogen gas as the precursor bubbler gas. Additionally, ammonia ($NH_3$) gas was used as nitrogen dopant. The as-grown polymerized thin films were analyzed using ellipsometry, Fourier-transform infrared [FT-IR] spectroscopy, UV-Visible spectroscopy, and water contact angle measurement. We found that with increasing plasma power, film thickness is gradually increased while optical transmittance is drastically decreased. However, under the same plasma condition, water contact angle is decreased with increasing $NH_3$ flow rate. The FT-IR spectra showed that the N-doped ethylcyclohexene plasma polymer films were completely fragmented and polymerized from ethylcyclohexane.

Study on Corrosion Resistance Performance of Zn Coating Applied by Arc Thermal and Plasma Arc Spray Process in Artificial Ocean Water (인공해양환경에서 Arc Thermal and Plasma Arc Spray 공법이 적용된 Zn 코팅 강재의 내식성능 평가에 관한 연구)

  • Jannat, Adnin Raihana;Lee, Han-Seung
    • Proceedings of the Korean Institute of Building Construction Conference
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    • 2020.06a
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    • pp.83-84
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    • 2020
  • In present study, we have deposited the Zinc coating using arc thermal spray and plasma arc spray processes onto the steel substrate and durability of the deposited coating was evaluated. The bond adhesion result shows that plasma arc sprayed Zn coating exhibited higher in its value compared to arc thermal spray. SEM shows that Zn coating deposited by plasma arc process is more compact, less porous and adherent compare to arc spray process. The corrosion resistance properties are evaluated in artificial ocean water solution with exposure periods. EIS results show that total impedance at 0.01 Hz of plasma arc sprayed coating is higher than arc thermal spray owing to the compact and less porous morphology. It is concluded that plasma arc sprayed Zn coating is better than arc thermal spray process.

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