• Title/Summary/Keyword: Cyclic treatment

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Preparation of Boron Doped Fullerene Film by a Thermal Evaporation Technique using Argon Plasma Treatment and Its Electrochemical Application

  • Arie, Arenst Andreas;Jeon, Bup-Ju;Lee, Joong-Kee
    • Carbon letters
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    • v.11 no.2
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    • pp.127-130
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    • 2010
  • Boron doped fullerene $C_{60}$ ($B:C_{60}$) films were prepared by the thermal evaporation of $C_{60}$ powder using argon plasma treatment. The morphology and structural characteristics of the thin films were investigated by scanning electron microscope (SEM), Fourier transform infra-red spectroscopy (FTIR) and x-ray photo electron spectroscopy (XPS). The electrochemical application of the boron doped fullerene film as a coating layer for silicon anodes in lithium ion batteries was also investigated. Cyclic voltammetry (CV) measurements were applied to the $B:C_{60}$ coated silicon electrodes at a scan rate of $0.05\;mVs^{-1}$. The CV results show that the $B:C_{60}$ coating layer act as a passivation layer with respect to the insertion and extraction of lithium ions into the silicon film electrode.

Effect of Surface Pretreatment on the Corrosion Resistance of Epoxy-Coated Carbon Steel

  • Lee, DongHo;Park, JinHwan;Shon, MinYoung
    • Corrosion Science and Technology
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    • v.11 no.5
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    • pp.165-172
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    • 2012
  • The corrosion resistance of epoxy-coated carbon steel was evaluated. The carbon steel surface was subjected to different treatment methods such as steel grit blasting with different size, steel shot ball blasting and power tool treatment. To study the effect of the treatments, the topology of the treated surface was observed by optical 3D microscopy and a pull-off adhesion test was conducted. The corrosion resistance of the epoxy-coated carbon steel was further examined by electrochemical impedance spectroscopy (EIS) combined with hygrothermal cyclic testing. The results of EIS indicated that the epoxy-coated carbon steel treated with steel grit blasting showed an improved corrosion resistance compared to untreated epoxy-coated surfaces or surfaces subjected to shot ball blasting and power tool treatments.

Treatment of Huge Chronic Tuberculous Empyema with Cardiopulmonary Dysfunction -1 case report- (심폐기능의 이상을 초래한 만성 결핵성 농흉의 치료 -1예 보고-)

  • 박준석;최용수;심영목
    • Journal of Chest Surgery
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    • v.37 no.2
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    • pp.188-192
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    • 2004
  • Treatment of huge chronic tuberculous empyema with cardiopulmonary dysfunction. Drainage of empyemal space by closed thoracostomy in chronic tuberculous empyema is generally contraindicated because of the possibility of empyema necessitatis and ascending infection. But in case that serious cardiopulmonary dysfunction is present, drainage of empyema and decompression is necessary. We experienced a case in which chronic tuberculous empyema was big enough to cause mediastinal shifting and cardiopulmonary failure. Immediate drainage of pleural cavity with tube thoracostomy was performed. Afterward, pleuropneumonectomy was done following cyclic irrigation for one month. The patient had successful postoperative course without any evidence of complication or relapse of infection.

Detection of Bio-chemical by Boron-doped Diamond Electrode (붕소가 도핑된 다이아몬드 전극을 이용한 생체화학물질의 검출)

  • Kim, Gyu-Sik;Einaga, Y.;Fujishima, A.;Park, Soo-Gil
    • Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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    • 2001.11b
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    • pp.569-572
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    • 2001
  • Selective. highly stable determination of epinephrine(adrenalin) was achieved in cyclic voltammetric measurement carried out at electrochemically treated conductive boron-doped diamond electrode. Boron-doped diamond electrodes were prepared on single crystal Si wafers by microwave plasma chemical vapor deposition and $B_{2}O_{3}$ was dissolved in acetone/methanol(9:1) mixture solution so that the B/C weight ratio ca. $10^{4}ppm$. Epinephrine is a kind of catecholamines, which secreted from adrenal marrow cells. The serious problem to detection of epinephrine is the interference phenomena of electroactive constituent. including AA. In this study. electrochemical treatment of BDD was carried out to discriminate between epinephrine and AA responses. Experimental results showed that the peak potential of AA oxidation shift to the positive direction and the oxidation peak of epinephrine was unchanged. The effect of electrochemical treatment was maintained up to 40hrs.

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A Study on the Recycling of Metals and Removal of Organics By Electrochemical Treatment of Mixed Waste Water of Surface Finishing Industry (표면처리 공정에서 발생하는 혼합 폐수의 전기화학적 처리에 의한 중금속의 재활용 및 유기물의 제거에 관한 연구)

  • 김영석;이중배
    • Journal of the Korean institute of surface engineering
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    • v.36 no.2
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    • pp.184-193
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    • 2003
  • Cyclic sweep voltametry was performed to investigate the electrochemical behavior of heavy metal ions and the organic additives in surface finishing process. And electrolysis using parallel plate electrode electrolyzer was carried out to simulate the treatment of real waste water. Results showed that more than 99 percent of Cu was recovered and selective recovery of Cu in mixed waste water was possible, but the possibility of economical recovery of Ni and Cr were very low due to the evolution of hydrogen gas. Electrochemical oxidation of cyanide and organic additives on anode showed very excellent removal rate. The complete removal of several hundred ppm of cynide was possible within several tens minutes and organics within 2 or 3 hours. Even in case of concentrate waste water, the complete removal of COD by using NaCl and air stirring seemed to be possible.

A Study on the Effect of Corrosion Resistance According to the Composition Variety of C, Cr, N in Duplex Stainless Steel

  • Kim, Hyeong-Jin;Cho, Kye-Hyun;Jung, Jae-young
    • Corrosion Science and Technology
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    • v.3 no.5
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    • pp.179-186
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    • 2004
  • Recently the alloy development of duplex stainless steel has been done. On this study we studied the effect of the corrosion resistance according to the composition variety of C, Cr, N in the alloy elements of duplex stainless steel. materials which have below 0.1[mm/year] corrosion rate enable to use for corrosion-resisting materials, generally. On this experiment we inspected the effect of the composition variety of C, Cr, N in duplex stainless steel and the heat treatment, which the condition was the water quenching after the heat treatment for 1hr. The experiment was done on the basis of the ASTM G48A test, Critical pitting temperature(CPT), and ASTM G-61(Electrochemical tests for cyclic polarization).

Detection of Bio-chemical by Boron-doped Diamond Electrode (붕소가 도핑된 다이아몬드 전극을 이용한 생계화학물질의 검출)

  • ;榮長 泰明;藤嶋 昭
    • Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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    • 2001.11a
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    • pp.569-572
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    • 2001
  • Selective, highly stable determination of epinephrine(adrenalin) was achieved in cyclic voltammetric measurement carried out at electrochemically treated conductive boron-doped diamond electrode. Boron-doped diamond electrodes were prepared on single crystal Si wafers by microwave plasma chemical vapor deposition and B$_2$O$_3$ was dissolved in acetone/methanol(1:1) mixture solution so that the B/C weight ratio ca. 10$^3$ppm.. Epinephrine is a kind of catecholamines, which secreted from adrenal marrow cells. The serious problem to detection of epinephrine is the interference phenomena of electroactive constituent, including AA. In this study, electrochemical treatment of BDD was carried out to discriminate between epinephrine and AA responses. Experimental results showed that the peak potential of AA oxidation shift to the positive direction and the oxidation peak of epinephrine was unchanged. The effect of electrochemical treatment was maintained up to 40hrs.

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Current concepts of craniofacial fibrous dysplasia: pathophysiology and treatment

  • Dong Yeon Kim
    • Archives of Craniofacial Surgery
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    • v.24 no.2
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    • pp.41-51
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    • 2023
  • Fibrous dysplasia is an uncommon genetic disorder in which bone is replaced by immature bone and fibrous tissue, manifesting as slow-growing lesions. Sporadic post-zygotic activating mutations in GNAS gene result in dysregulated GαS-protein signaling and elevation of cyclic adenosine monophosphate in affected tissues. This condition has a broad clinical spectrum, ranging from insignificant solitary lesions to severe disease. The craniofacial area is the most common site of fibrous dysplasia, and nine out of 10 patients with fibrous dysplasia affecting the craniofacial bones present before the age of 5. Surgery is the mainstay of treatment, but the technique varies according to the location and severity of the lesion and associated symptoms. The timing and indications of surgery should be carefully chosen with multidisciplinary consultations and a patient-specific approach.

Inactivation of Wilt Pathogen(Fusarium oxysporum f. sp.) using Plasma in Tomato Hydroponic Cultivation (토마토 수경재배에서 플라즈마를 이용한 시들음병균(Fusarium oxysporum f. sp.) 불활성화)

  • Dong-Seog Kim;Young-Seek Park
    • Journal of Environmental Science International
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    • v.33 no.5
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    • pp.323-332
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    • 2024
  • Circulating hydroponic cultivation has the advantage of reducing soil and water pollution problems caused by discharge of fertilizer components because the nutrient solution is reused. However, cyclic hydroponic cultivation has a low biological buffering capacity and can cause outbreaks of infectious root pathogens. Therefore, it is necessary to develop technologies or disinfection systems to control them. This study used dielectric barrier discharge plasma, which generates various persistent oxidants, to treat Fusarium oxysporum f. sp., a pathogen that causes wilt disease. Batch and intermittent continuous inactivation experiments were conducted, and the results showed that the total residual oxidant was persistent in intermittent plasma treatment at intervals of 2-3 days, and F. oxysporum was treated efficiently. Intermittent plasma treatment did not inhibit the growth of tomatoes.

Effect of cAMP on the Replication of Human Cytomegalovirus (Human cytomegalovirus 증식에 미치는 cAMP의 영향)

  • 지용훈;윤주현;이찬희
    • Korean Journal of Microbiology
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    • v.31 no.1
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    • pp.72-78
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    • 1993
  • Since the 'promoter/enhancer region of the major immediate early (IE) ~ene of human cytomegalovirus (HCMV) contains the cyclic AMP (cAMP) response element (CRE) consensus sequence, it was reasonable to hypothesize that cAMP might affect HCMV replication. Cyclic AMP modulating drugs such as 8-bromoadenosine 3',5'-cyclic monophosphate (BrA), and papaverine were used to affect the intracellular levels of cAMP, and the effects of the drugs on HCMV replication were studied. While papaverine effectively inhibited HCMV multiplication and DNA synthesis, BrA exerted little effect on the production of infectious HCMV yields. The synthesis of DNA in HCMV-infected cells appeared to be stimulated by BrA In order to understand the effect of cAMP on the expression of HCMV major IE gene, plasmid (pCMVIE/CAT) containing a reporter gene driven by HCMV IE promoter was transfected into either permissive human embryo lung (HEL) cells or nonpermissive cells. PL,Javerine, which has been reported to block the HCMV-induced increase in cAMP, reduced the expression of pCMVIE/CA T in permissive HEL cells. Treatment of transfected cells with BrA increased the expression of HCMV major IE promoter not only in HEL cells, but also in nonpermissive HeLa and Vero cells. Therefore, it seems that the expression of HCMV major IE gene is regulated by cAMP.

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