• Proceedings of the Korean Radioactive Waste Society Conference
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• 2017.10a
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• pp.73-73
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• 2017

Pyroprocessing at KAERI (Korea Atomic Energy Research Institute) consists of pretreatment, electroreduction, electrorefining and electrowinning. SFR (Sodium Fast Reactor) fuel is prepared from the electrowinning process which is composed of LCC (Liquid Cadmium Process) and Cd distillation et al. LCC is an electrochemical process to obtain actinides from spent fuel. In order to recover actinides inert anodes such as carbon material are used, where chlorine gas ($Cl_2$) evolves on the surface of the carbon material. And, stainless steel (SUS) crucible should be installed in large-scale electrowinning system. Therefore, the effect of chlorine on the SUS material needs to be studied. LiCl-KCl-$UCl_3$-$NdCl_3$-$CeCl_3$-$LaCl_3$-$YCl_3$ salt was contained in 2 kinds of electrolytic crucible having an inner diameter of 5cm, made of an insulated alumina and an SUS, respectively. And, three kinds of electrodes such as cathode, anode, reference were used for the electrochemical experiments. Both solid tungsten (W) and LCC were used as cathodes. Cd of 45 g as the cathode material was contained in alumina crucibles for the deposition experiments, where the crucible has an inner diameter of 3 cm. Glassy carbon rod with the diameter of 0.3 cm was employed as an anode, where shroud was not used for the anode. A pyrex tube containing LiCl-KCl-1mol% AgCl and silver (Ag) wire having a diameter of 0.1cm was used as a reference electrode. Electrodeposition experiments were conducted at $500^{\circ}C$ at the current densities of $50{\sim}100mA/cm^2$. In conclusion, Fe ions were produced in the salt during the electrodeposition by the reaction of chlorine evolved from the anode and Fe of the SUS crucible and thereby LCC system using SUS crucible showed very low current efficiencies compared with the system using the insulated alumina crucible. Anode shroud needs to be installed around the glassy carbon not to influence surrounding SUS material.

• The Korean Journal of Physiology and Pharmacology
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• v.26 no.2
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• pp.125-133
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• 2022

Carbon monoxide (CO) is a known gaseous bioactive substance found across a wide array of body systems. The administration of low concentrations of CO has been found to exert an anti-inflammatory, anti-apoptotic, anti-hypertensive, and vaso-dilatory effect. To date, however, it has remained unknown whether CO influences atrial natriuretic peptide (ANP) secretion. This study explores the effect of CO on ANP secretion and its associated signaling pathway using isolated beating rat atria. Atrial perfusate was collected for 10 min for use as a control, after which high atrial stretch was induced by increasing the height of the outflow catheter. Carbon monoxide releasing molecule-2 (CORM-2; 10, 50, 100 μM) and hemin (HO-1 inducer; 0.1, 1, 50 μM), but not CORM-3 (10, 50, 100 μM), decreased high stretch-induced ANP secretion. However, zinc porphyrin (HO-1 inhibitor) did not affect ANP secretion. The order of potency for the suppression of ANP secretion was found to be hemin > CORM-2 >> CORM-3. The suppression of ANP secretion by CORM-2 was attenuated by pretreatment with 5-hydroxydecanoic acid, paxilline, and 1H-[1,2,4] oxadiazolo [4,3-a] quinoxalin-1-one, but not by diltiazem, wortmannin, LY-294002, or NG-nitro-L-arginine methyl ester. Hypoxic conditions attenuated the suppressive effect of CORM-2 on ANP secretion. In sum, these results suggest that CORM-2 suppresses ANP secretion via mitochondrial K_ATP channels and large conductance Ca²⁺-activated K⁺ channels.

• Korean Journal of Veterinary Research
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• v.51 no.4
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• pp.259-265
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• 2011

Several compounds and extracts isolated from a brown alga, Ishige (I.) okamurae, exhibit anti-oxidant and anti-inflammatory effects. The present study investigated whether the ethyl acetate (EtOAc) fraction of I. okamurae (EFIO) could ameliorate carbon tetrachloride ($CCl_{4}$)-induced hepatotoxicity in rats. Sprague-Dawley rats were intraperitoneally (i.p.) administered with EFIO at 10 or 50 mg/kg per day for 2 consecutive days before $CCl_{4}$ injection (3.3 mL/kg, i.p.). Twenty four hours later, the rats were anesthesized with diethyl ether and dissected. Pretreatment with EFIO significantly reduced the increased serum levels of alanine aminotransferase and aspartate aminotransferase in $CCl_{4}$-treated rats. Pretreatment with EFIO also significantly inhibited the reduced activities of superoxide dismutase and catalase in the $CCl_{4}$-injured liver. Histopathological evaluations showed that hemorrhage, hepatocyte necrosis, inflammatory cell infiltration, and fatty degeneration induced by $CCl_{4}$ treatment were ameliorated by the administration of EFIO. Additionally, liver immunohistochemical analyses revealed the marked reduction in ED1-positive monocyte-like macrophages in EFIO-pretreated rats given $CCl_{4}$. These results suggest that EFIO ameliorates $CCl_{4}$-induced liver injury, possibly through the inhibition of oxidative stress.

• Korean Journal of Veterinary Research
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• v.32 no.3
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• pp.347-356
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• 1992

In oriental medicine, Artemisia Iwayomogi(Compositae) has been used clinically for jaundice, hepatitis, liver cirrhosis etc. The purposes of present study were to examine pharmacological effects of Artemisia lwayomogi water extract(AIWE) on weights of body, liver, kidney, spleen and adrenal, and on biochemical parameters (activities of AST, ALT and LDH, contents of cholesterol and triacylglycerol, and levels of hepatic lipid peroxide) against hepatic injury by carbon tetrachloride($CCl_4$) in rats. The results were as follow; 1. Body weights were reduced by $CCl_4$. In AIWE pretreatment groups, reduction of body weights was inhibited at 48 hours. Increased liver weights by $CCl_4$ were reduced in proportion to numbers of treatment of AIWE in AIWE pre- and posttreatment groups. Increased kidney weights by $CCl_4$ were reduced in AIWE pretreatment groups at 72 hours. Increased weights of spleen and adrenal by $CCl_4$ were not affected by AIWE treament. 2. Increased AST activities by $CCl_4$ were significantly (p<0.05) decreased in AIWE posttreatment groups at 48 and 72 hours. Increased ALT activities by $CCl_4$ were significantly(p<0.05) decreased in AIWE posttreatment groups at 48 hours. Increased LDH activities by $CCl_4$ were very significantly (p<0.01, p<0.001) decreased in AIWE posttreatment groups at 48 and 72 hours, respectively. 3. Increased cholesterol contents by $CCl_4$ were significantly (p<0.05) decreased in AIWE posttreatment groups at 24 and 48 hours. Decreased triacylglycerol contents by $CCl_4$ were significantly (p<0.05) increased in AIWE posttreatment at 48 and 72 hours. 4. Increased hepatic lipid peroxide levels by $CCl_4$ were significantly (p<0.05, p<0.01) decreased in AIWE posttreatment groups at 48 and 72 hours, respectively. In conclusion, AIWE did not affect normal liver function and had property of antioxidant, due to reduced lipid peroxidation by $CCl_4$. AIWE seems to have hepatoprotective effects rather than direct preventive effects to $CCl_4$-induced necrotic degeneration of liver cell, cholestasis and damages in metabolism of lipid.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.18 no.2
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• pp.95-101
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• 2017

In this paper, the sizing removal condition for the pretreatment of composite materials is obtained numerically by applying an image processing algorithm and nickel-plated carbon fiber is fabricated by a dry process method to enhance its electromagnetic shielding performance. Sizings that are wrapped in a polymer type material during the manufacturing of carbon fiber should be removed for dry coating. A numerical value, that is the correlation, can be obtained by determining the regular pattern of the carbon fiber in the image taken by a scanning electron microscope (SEM) after the sizing is removed. The application of the proposed numerical method to the SEM image of the fiber after the sizing is removed with solution, compressed air, solution and compressed air (hybrid), showed that this method of eliminating the sizing is superior to the hybrid method. Then, by spreading the carbon fiber roll with the sizing removed, we were able to produce nickel plated carbon fiber by the roll-to-roll sputtering method. The electromagnetic shielding performance of the fabricated 30, 40 and 100 nickel coated carbon fibers was measured. The Korea Advanced Institute of Science and Technology evaluated the electromagnetic shielding performance of the 100 nickel-coated carbon fiber to have a maximum value of 73.2 (dB) and a minimum value of 66.7 (dB). This is similar to the electromagnetic shielding rate of copper and shows that this material can be used as a cable for EV / HEV automobiles.

• The Korean Journal of Pharmacology
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• v.17 no.1 s.28
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• pp.33-39
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• 1981

In this paper, the influences of adrenergic neuronal blockades of different mode: guanethidine and ${\alpha}$-methyl-para-tyrosine on the changes induced by carbon tetrachloride $(CCl_4)$ of hepatic total lipid, glycogen, and lipid peroxide contents and serum lactic dehydrogenase activity were investigated in male mice. The results obtained were summarized as follows: 1) The hepatic total lipid and lipid peroxide contents and serum lactic dehydrogenase activity were markedly increased by $CCl_4$, but hepatic glycogen content were decreased. 2) The hepatic total lipid and lipid peroxide contents and serum lactic dehydrogenase activity were not significantly changed by guanethidine(20mg/kg) or ${\alpha}$-methyl-para-tyrosine (5 mg/kg) injection. 3) The increase of hepatic total lipid induced by $CCl_4$ was inhibited by the pretreatment of guanethidine or ${\alpha}$-methyl-para-tyrosine, and the increase of hepatic lipid peroxide content induced by $CCl_4$ was slightly inhibited by them. But the decrease of hepatic glycogen content and the increase of serum lactic dehydrogenase activity induced by $CCl_4$ were not affected by them.

• Transactions of the Korean hydrogen and new energy society
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• v.2 no.1
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• pp.57-67
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• 1990

This study is proposed to investigate the effect of electrode preparation method for Alkaline Fuel Cell using NaOH as an electrolyte on the Fuel Cell performance. The materials used for the preparation of electrode are Pt and Ag on Vulcan XC-72. Surface area of Vulcan XC-72 have different values according to the pretreatment conditions and the dispersion of Pt is dependent on the impregnation Particle size of Pt impregnated on unpretreated carbon was observed to be $20{\sim}40{\AA}$ and that on pretreated carbon in $N_2$ stream at $950^{\circ}C$ was found to be finely dispersed less then $15{\AA}$. The electrode performance was affected by the particle size of metals and operating temperature. It was revealed from this study that the optimum particle size about $30{\AA}$ and optimum temperature range is between $90{\sim}100^{\circ}C$.

• New & Renewable Energy
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• v.6 no.2
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• pp.27-32
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• 2010

Low Calorific Gas Turbine (LCGT) has been developed as a next generation power system using landfill gas (LFG) and biogas made from various organic wastes, food Waste, waste water and Livestock biogas. Low calorific fuel purification by pretreatment system and carbon dioxide fixation by green house system are very important design target for the optimum applications of LCGT. Main troubles of Low Calorific Gas Turbine system was derived from the impurities such as hydro sulfide, siloxane, water contained in biogas. Even if the quality of the bio fuel is not better than natural gas, LCGT may take low quality gas fuel and environmental friendly power system. The mechanical characterisitics of LCGT system is a high energy efficiency (>70%), wide range of output power (30 kW - 30 MW class) and very clean emission from power system (low NOx). A green house has been designed for four different carbon dioxide concentration from ambient air to 2000 ppm by utilizing the exhaust gas and hot water from LCGT system. LCGT is expected to contribute achieving the target of Renewable Portfolio Standards (RPS).

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2003.07b
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• pp.779-782
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• 2003

Hot filament 플라즈마 화학기상 증착법 (HFPECVD)를 사용하여 전처리 조건에 따른 탄소나노튜브의 성장 특성을 관찰하였다. 암모니아 ($NH_3$)를 희석가스로 사용하였고, 아세틸렌 ($C_2H_2$)를 탄소 원료가스로 각각 사용하였다. 암모니아 가스 플라즈마를 사용하여 전처리 된 니켈 촉매 층의 SEM (Scanning Electron Microscopy) 이미지를 관찰하여 본 결과, 나노 사이즈의 촉매 그레인(grain)을 발견할 수 있었다. 그리고 탄소 나노튜브의 직경과 성장 밀도 또한 전처리 된 촉매 층에 따라 다른 양상을 보였다. TEM (Transmission Electron Microscopy)를 사용하여 탄소나노튜브를 관찰한 결과 공동구조(hollow)를 한 다중벽 탄소 나노튜브(MWCNT)를 관찰할 수 있었다. 성장된 나노튜브는 끝에 금속팁을 가지고 있으며, 나노튜브의 팁은 촉매로 사용한 것과 같은 물질로 구성되어 있었다. Raman spectroscopy를 사용하여 측정된 B-밴드와 G-밴드의 피크들은 각각 $1360cm^{-1}$와 $1598cm^{-1}$ 부근에서 나타났으며, 전처리 조건을 달리하여 성장시킨 탄소나노튜브 필름에서 이들 두 피크의 위치는 이동하지 않았고, 두 피크의 강도 비율 ($I_G/I_D$)은 전처리 조건에 따라 변하였다.

• Toxicological Research
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• v.11 no.2
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• pp.273-277
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• 1995

Several metabolic modulators on the generation of carbon monoxide (CO)from dichloromethane (DCM) was examined in adult female rats. It has been known that DCM is converted to CO by cytochrome P-450 or to carbon dioxide $(CO_2)$ by glutathione-dependent metabolic reaction. In rats treated with DCM (3 mmol/kg, ip) only, the carboxyhemoglobin (COHb) level reached a peak of approximately 10% 2 or 3 hr following the treatment. Disulfiram (300 mg/kg, ip) or allylsulfide (200 mg/kg, po), both known as a selective inhibitior for cytochrome P-450 2E1, blocked the increase in COHb concentratlons almost completely suggesting that the metabolic conversion of DCM to CO is mediated by the activity of this specific type of isozyme. YH439 (125 or 250 mg/kg, po), a potential hepatoprotective agent, decreased the COHb elevation as well indicating that this chemical is a potent inhibitor for 2E1. In rats treated with pyrazine (200 mg/kg, ip) 18 hr prior to DCM the peak COHb concentration was decreased by approximately 3 or 4%. However, pretreatment of rats with pyrazine either 24 or 48 hr before DCM increased the peak COHb concentration significantly compared to the rats treated with DCM only. The results in the present study strongly suggest that the generation of CO from DCM depends on the 2E1 activity and that the pharmacological and/or toxicological action of YH439 or pyrazine in animals or human is associated with its effect on this isozyme.