• Title/Summary/Keyword: proton pump

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Model Based Hardware In the Loop Simulation of Thermal Management System for Performance Analysis of Proton Exchange Membrane Fuel Cell (고분자전해질 연료전지 특성 해석을 위한 열관리 계통 모델 기반 HILS 기초 연구)

  • Yun, Jin-Won;Han, Jae-Young;Kim, Kyung-Taek;Yu, Sang-Seok
    • Transactions of the Korean hydrogen and new energy society
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    • v.23 no.4
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    • pp.323-329
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    • 2012
  • A thermal management system of a proton exchange membrane fuel cell is taken charge of controlling the temperature of fuel cell stack by rejection of electrochemically reacted heat. Two major components of thermal management system are heat exchanger and pump which determines required amount of heat. Since the performance and durability of PEMFC system is sensitive to the operating temperature and temperature distribution inside the stack, it is necessary to control the thermal management system properly under guidance of operating strategy. The control study of the thermal management system is able to be boosted up with hardware in the loop simulation which directly connects the plant simulation with real hardware components. In this study, the plant simulation of fuel cell stack has been developed and the simulation model is connected with virtual data acquisition system. And HIL simulator has been developed to control the coolant supply system for the study of PEMFC thermal management system. The virtual data acquisition system and the HIL simulator are developed under LabVIEWTM Platform and the Simulation interface toolkit integrates the fuel cell plant simulator with the virtual DAQ display and HIL simulator.

Hydrogen Permeation of SrCe0.95Gd0.05O3-α-Ce0.9Gd0.1O2-β Proton-Conducting Ceramic Membranes (프로톤 전도성 SrCe0.95Gd0.05O3-α-Ce0.9Gd0.1O2-β 복합체 멤브레인의 수소투과 특성)

  • Kim, Hwan-Soo;Yu, Ji-Haeng;Shin, Min-Jae
    • Transactions of the Korean hydrogen and new energy society
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    • v.22 no.2
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    • pp.161-167
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    • 2011
  • Proton conductors have attracted considerable attention for solid oxide fuel cell (SOFC), hydrogen pump, gas sensor, and membrane separators. Doped $SrCeO_3$ exhibits appreciable proton conductivity in hydrogen-containing atmosphere at high temperature. However commercial realization has been hampered due to the reactivity of $SrCeO_3$ with $CO_2$. The chemical stability and proton conductivity are dependent on dopant type. The purpose of this work is to investigate chemical stability of $SrCe_{0.95}Gd_{0.05}O_{3-\alpha}-Ce_{0.9}Gd_{0.1}O_{2-\beta}$ composites in $CO_2$ and $H_2$ gases. Thermogravimetric analysis (TGA) was performed in gaseous $CO_2$ and electrical conductivity of the composites were also measured between 500 and $900^{\circ}C$ in air and $H_2$ atmosphere. $SrCe_{0.95}Gd_{0.05}O_{3-\alpha}-Ce_{0.9}Gd_{0.1}O_{2-\beta}$ composite membranes showed good chemical stability of in $CO_2$ atmosphere and high conductivity at hydrogen condition. The hydrogen permeation of $SrCe_{0.95}Gd_{0.05}O_{3-\alpha}-Ce_{0.9}Gd_{0.1}O_{2-\beta}$ composite membranes was investigated as a function of volumetric content of $SrCe_{0.95}Gd_{0.05}O_{3-\alpha}$. The $SrCe_{0.95}Gd_{0.05}O_{3-\alpha}-Ce_{0.9}Gd_{0.1}O_{2-\beta}$(6:4) membrane with a thickness of 1.0 mm showed the highest hydrogen permeability with the flux reaching of 0.12 $ml/min{\cdot}cm^2$ at $800^{\circ}C$ in 100%$H_2/N_2$ as feed gas.

Physiological Responses of Hairy Roots of Ginseng (Panax ginseng C.A. Meyer) to Iron Status and pH Change (배지의 철이온과 pH 변화에 대한 인삼모상근의 생리적 반응)

  • 양덕조;윤길영;김용해;양덕춘
    • Korean Journal of Plant Tissue Culture
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    • v.27 no.1
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    • pp.31-37
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    • 2000
  • Proton extrusion by hairy roots of Panax ginseng C.A. Meyer was enhanced by iron-deficiency or single salt solutions of nitrate or ammonium salts. The enhancement effect of iron-deficiency was confined to the apical zones, whereas that of nitrate and ammonium was confined to the basal root zones. tinder iron-deficiency medium, the proton extrusion of ginseng hairy roots was higher at two times than that grown in the medium of iron-sufficiency. According to pH in the medium, uptake of inorganic elements showed various patterns for the kind of inorganic elements. $Ca^{2+}$, $Mg^{2+}$ and Fe$^{2+}$ were highest uptake at the pH 4.8 and Mn$^{2+}$, Zn$^{2+}$ and Cu$^{2+}$ were highest uptake at the pH 3.8. Free sugars and ginsenosides were analyzed by HPLC. Five kinds of free sugars were indentified in ginseng hairy roots. Glucose, fructose and sucrose were a major sugar in ginseng hairy roots and contents of free sugars were highest at pH 6.8 and pH 4.8, respectively. The contents of ginsenosides and phenolic compounds were highest at pH 5.8. This physiological responses in ginseng hairy root indicated that it may well be a good model system for the study of mechanism of mobilization and uptake of inorganic elements related with the red-colored phenomenon in ginseng roots.

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Pharmacological properties of YJA 20379-1

  • Lee, Eun-Bang;Cheon, Sun-A;Cho, Sung-Ig;Lee, Eun-Shim;Man- Sik Chang;Park, Wahn-Soo;Kim, Kyu-Bong
    • Proceedings of the Korean Society of Applied Pharmacology
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    • 1997.04a
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    • pp.96-96
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    • 1997
  • YJA 20379-1(YJA-1)은 영진약품(주)에서 합성한 Thiazole유도체로서 급만성 위궤양 및 십이지장 궤양에 유효한 proton pump 억제 작용물질이다. 이 실험은 신약개발을 지향한 한 단계로서 YJA-1의 일반약리작용에 관한 것이다. 실험은 YJA-1에 대하여 중추신경계작용, 진통작용, 정상체온에 대한 작용, 항경련작용 및 장수송능시험을 실시하였고, 용량은 50, 100 및 200$\mu\textrm{g}$/$m\ell$를 경구투여하였고, 혈압 및 호흡에의 작용은 토끼에 10, 20 및 40mg/kg을 정맥주사하여 실시하였으며, 적출장기 실험에서는 100 및 200$\mu\textrm{g}$/$m\ell$를 적용시켰다.

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Pain medication and long QT syndrome

  • Klivinyi, Christoph;Bornemann-Cimenti, Helmar
    • The Korean Journal of Pain
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    • v.31 no.1
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    • pp.3-9
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    • 2018
  • Long QT syndrome is a cardiac repolarization disorder and is associated with an increased risk of torsades de pointes. The acquired form is most often attributable to administration of specific medications and/or electrolyte imbalance. This review provides insights into the risk for QT prolongation associated with drugs frequently used in the treatment of chronic pain. In the field of pain medicine all the major drug classes (i.e. NSAIDs, opioids, anticonvulsive and antidepressant drugs, cannabinoids, muscle relaxants) contain agents that increase the risk of QT prolongation. Other substances, not used in the treatment of pain, such as proton pump inhibitors, antiemetics, and diuretics are also associated with long QT syndrome. When the possible benefits of therapy outweigh the associated risks, slow dose titration and electrocardiography monitoring are recommended.

Antifungal Activity of Medium-chain Saturated Fatty Acids and Their Inhibitory Activity to the Plasma Membrane H+-ATPase of Fungi (중급 지방산 항진균 활성과 진균의 Plasma membrane H+-ATPase에 대한 저해작용)

  • 이상화;김창진
    • Microbiology and Biotechnology Letters
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    • v.27 no.5
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    • pp.354-358
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    • 1999
  • In order to know the antifungal characteristics of saturated fatty acids having 6 to 12 carbons, their minimum inhibitory concentrations (MICs) and minimum fungicidal concentrations (MFCs) were estimated against Saccharomyces cerevisiae. Fatty acids from C6 to C11 exhibited increasing activity with chain length, but C12 fatty acid did not show activity at all. In relation to antifungal modes of actions, fatty acids investigated showed on inhibitory activity toward the plasma membrane H+-ATPase of Saccharomyces cerevisiae. Their inhibitions to the glucose-induced acidification and ATP hydrolysis caused by the proton pump were found to be in common wiht antifungal activities. At the test concentration of 1mM, hexanoic acid (C6) showed the lowest inhibition of about 30%, while undecanoic acid(C11) showed the strongest inhibition of over 90%. In addition, as seen with antifungal activity, the inhibitory activity of dodecanoic acid (C12) was suddenly reduced to less than 50%.

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Inquiry into the Laboratory Diagnostic Tests in Larygopharyngeal Reflux Disease (인후두역류질환의 실험실 검사의 재평가)

  • Kim, Han-Su
    • Journal of the Korean Society of Laryngology, Phoniatrics and Logopedics
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    • v.18 no.2
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    • pp.102-107
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    • 2007
  • Laryngopharyngeal reflux disease (LPRD) is the result of retrograde flow of gastric contents to the laryngopharynx. Laryngoscopic findings and special questionnaires are first step of diagnosis of LPRD. Empiric trials of Proton pump inhibitor' test (PPI test) is recommended as treatment and diagnosis. However confirmation of reflux is then recommended primarily in patients with persistent symptoms despite acid-suppressive therapy. The 24 hour ambulatory double pH monitoring has been a gold standard method in diagnosis of LPRD even though it has some limitation. The combined multichannel intraluminal impedance and pH monitoring is a new-rising test tool. It can detect acid/non-acid, liquid/gaseous reflux and clearance of refluxate. The water siphon test is also used for diagnosis of LPRD.

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Globus Pharyngeus : The Psychiatric Perspective (인후두 이물감의 정신과적 접근)

  • Joo, Young-Hoon
    • Journal of the Korean Society of Laryngology, Phoniatrics and Logopedics
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    • v.27 no.2
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    • pp.84-86
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    • 2016
  • Globus pharyngeus or globus sensation is the painless sensation of a lump in the throat and may be described as a foreign body sensation, a tightening or choking feeling. It is often associated with persistent clearing of the throat, chronic cough, hoarseness, and catarrh. Its etiology remains unclear ; however, laryngopharyngeal reflux may play a role in a subset of patients. Psychogenic problems have often been thought to cause or trigger the globus sensation. Personality studies have found higher levels of alexithymia, neuroticism, and psychological distress (including anxiety, low mood, and somatic concerns) and lower levels of extraversion in patients presenting with globus. Globus patients with laryngopharyngeal reflux exhibited weaker psychological symptoms than non- laryngopharyngeal reflux globus patients, and globus patients who did not respond to proton pump inhibitor had significantly higher anxiety scores. In cases with negative clinical investigations and consistent globus symptom, other treatment strategies, including speech therapy, antidepressants, and cognitive-behavioral therapy, should be considered.

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Renal Tubular Acidosis (신세뇨관 산증)

  • Park, Hye-Won
    • Childhood Kidney Diseases
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    • v.14 no.2
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    • pp.120-131
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    • 2010
  • Renal tubular acidosis (RTA) is a metabolic acidosis due to impaired excretion of hydrogen ion, or reabsorption of bicarbonate, or both by the kidney. These renal tubular abnormalities can occur as an inherited disease or can result from other disorders or toxins that affect the renal tubules. Disorders of bicarbonate reclamation by the proximal tubule are classified as proximal RTA, whereas disorders resulting from a primary defect in distal tubular net hydrogen secretion or from a reduced buffer trapping in the tubular lumen are called distal RTA. Hyperkalemic RTA may occur as a result of aldosterone deficiency or tubular insensitivity to its effects. The clinical classification of renal tubular acidosis has been correlated with our current physiological model of how the nephron excretes acid, and this has facilitated genetic studies that have identified mutations in several genes encoding acid and base ion transporters. Growth retardation is a consistent feature of RTA in infants. Identification and correction of acidosis are important in preventing symptoms and guide approved genetic counseling and testing.