• Title/Summary/Keyword: chemical modifying

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Microbial Fuel Cells for Bioenergy Generation and Wastewater Treatment (바이오에너지 생산 및 폐수처리를 위한 미생물연료전지)

  • Nah, Jaw-Woon;Roh, Sung-Hee
    • Applied Chemistry for Engineering
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    • v.24 no.6
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    • pp.567-578
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    • 2013
  • A microbial fuel cell (MFC) is a bio-electrochemical device that converts chemical energy in the chemical bonds in organic compounds to electrical energy through catalytic reactions of microorganisms under anaerobic conditions. Power density and Coulombic efficiency are significantly affected by the types of microbe in the anodic chamber of an MFC, configurations of the system and operating conditions. The achievable power output from MFC increased remarkably by modifying their designs such as the optimization of MFC configurations, the physical and chemical operating conditions, and the choice of biocatalysts. This article presents a critical review on the recent advances made in MFC research with the emphasis on MFC configurations, optimization of important operating parameters, performances and future applications of MFC.

Forming Technology of Stainless Steel Sheet for Automotive Muffler Part (자동차 머플러의 스테인리스 강판 성형기술에 관한 연구)

  • Park, D.H.;So, B.S.;Bae, W.R.;Cho, Y.;Kim, T.J.;Ko, T.J.
    • Proceedings of the Korean Society for Technology of Plasticity Conference
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    • 2008.10a
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    • pp.230-233
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    • 2008
  • Stainless steels are alloy steels with iron as the primary constituent and chromium, nickel, and manganese as principal alloying elements. In addition to automotive, construction, and transportation industries, stainless steels have a variety of applications in the food, chemical, and pharmaceutical industries. Some common products made from stainless steel are sinks, wash basins, kitchen vessels, and cutlery. Among ferritic stainless steels, type 409 can be cold-formed easily and are used for deep-drawn parts such as vessels for the chemical and food industries. In this study, forming analyses and experiments to prevent the occurrence of inferiority such as wrinkles, crack, and neck for automotive muffler part are carried out to save the optimal conditions during forming by modifying the blank size and shape, blank holding force etc.

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Design and Synthesis of Resin-Conjugated Tamiflu Analogs for Affinity Chromatography

  • Kimura, Yasuaki;Yamatsugu, Kenzo;Kanai, Motomu;Echigo, Noriko;Kuzuhara, Takashi;Shibasaki, Masakatsu
    • Bulletin of the Korean Chemical Society
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    • v.31 no.3
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    • pp.588-594
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    • 2010
  • Two types of resin-conjugated Tamiflu analogs were synthesized by modifying our original synthetic route of oseltamivir phosphate (Tamiflu). The prepared resins bound to influenza virus neuraminidase, the main target of Tamiflu. The resins will be useful for isolating and identifying presumed endogenous vertebrate proteins that interact with Tamiflu, which might relate to the rarely observed abnormal behavior exhibited by some influenza patients treated with Tamiflu.

STARDUSTS IN SUPERNOVA REMNANTS SEEN BY AKARI

  • Koo, Bon-Chul
    • Publications of The Korean Astronomical Society
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    • v.27 no.4
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    • pp.225-230
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    • 2012
  • Supernovae (SN) and supernova remnants (SNRs) play a major role in the life-cycle of interstellar dusts. Fast shock waves generated by SN explosions sweep out the interstellar space destroying dust grains and modifying their physical and chemical properties. The dense, cooling SN ejecta, on the other hand, provide an environment for dusts to condense. Recent space-infrared telescopes have revealed the hidden universe related to these fascinating microscopic processes. In this paper, I introduce the results on stardusts in young core-collapse supernova remnants obtained by AKARI. The AKARI results show diverse infrared characteristics of stardusts associated with SNRs, implying diverse physical/chemical stellar structures and circumstellar environments at the time of explosion.

Fabrication of a Superhydrophobic Surface with Adjustable Hydrophobicity and Adhesivity Based on a Silica Nanotube Array

  • Yu, Jae-Eun;Son, Sang-Jun
    • Bulletin of the Korean Chemical Society
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    • v.33 no.10
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    • pp.3378-3382
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    • 2012
  • A superhydrophobic surface with a water contact angle > $150^{\circ}$ has attracted great interest from both fundamental and practical aspects. In this study, we demonstrated that hydrophobicity of a silica nanotube (SNT) array can be easily controlled by the SNT aspect ratio. In addition, the adhesive and anti-adhesive properties were controlled without modifying the hydrophobic surface. Various silica structures on a polydimethylsiloxane substrate were prepared using the desired alumina template. Bundle-arrayed and bowl-arrayed silica surfaces exhibited extraordinary superhydrophobicity due to the large frontal surface area and hierarchical micro/nanostructure. As the strategy used in this study is biocompatible and a wide range of hydrophobicities are capable of being controlled by the SNT aspect ratio, a hydrophobic surface composed of an SNT array could be an attractive candidate for bioapplications, such as cell and protein chips.

Preparation and Investigation on Swelling and Drug Delivery Properties of a Novel Silver/Salep-g-Poly(Acrylic Acid) Nanocomposite Hydrogel

  • Bardajee, Ghasem Rezanejade;Hooshyar, Zari;Kabiri, Firozeh
    • Bulletin of the Korean Chemical Society
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    • v.33 no.8
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    • pp.2635-2641
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    • 2012
  • Novel silver/salep-g-poly(acrylic acid) nanocomposite hydrogel were prepared in aqueous solution using poly(acrylic acid) grafted onto salep as a biopolymer based material. FT-IR spectra confirmed that poly(acrylic acid) (PAA) had been grafted onto salep in graft copolymerization reaction. TEM observations showed that silver nanoparticles have been uniformly dispersed in polymeric matrix. Effects of pH, acrylic acid (AA) amount and silver ion concentration on swelling capabilities were investigated. Results indicate that modifying AA and silver ion can improve swelling properties of the resultant nanocomposite hydrogel. pH response of this nanocomposite hydrogel in acidic and neutral pH made it suitable for drug delivery applications.

Chemical modifying agents of radiation effect (방사선조사(放射線照射)의 생물학적효과(生物學的效果)에 영향을 미치는 약제(藥劑))

  • Han, Man-Chung;Chang, Kee-Hyun
    • Journal of Radiation Protection and Research
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    • v.5 no.1
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    • pp.32-35
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    • 1980
  • A number of chemical compounds that modify radiation effects are reviewed, with brief report of our own experiments on radioprotective effect of some vasoconstrictive agents and 5-Thio-D-Glucose. Sulfhydryl compounds(-SH group) and some pharmacologic compounds such as CNS depresants, vasoconstrictive agents and autonomic drugs are known to have radioprotective effect in experimental research and in limitted clinical study, whereas oxygen, hallogenated pyrimidines and metronidazole, etc. have radiosensitizing effect. Author experimentally observed some radioprotective effects of angiotensin II, a strong vasoconstrictor, and 5-Thio-D-glucose in mice.

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Development of Implemental Procedure for K-Risk Based Inspection (한국형 위험기반검사(K-RBI)의 절차 개발)

  • Lee, Hern-Chang;Shin, Pyong-Sik;Lim, Dae-Sik;Kim, Tae-Ok
    • Journal of the Korean Society of Safety
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    • v.21 no.3 s.75
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    • pp.31-37
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    • 2006
  • To apply easily the K-RBI program in domestic industries, an implemental procedure for K-RBI program was prepared. The K-RBI program had been developed, based on API-581 BRD. Therefore, through the usage of the developed K-RBI program and the implemental procedure, industries would have a benefit from reduced costs by modifying a frequency of an inspection efficiently. Also, the reliability of facilities would be maximized through improvement of an inspection method for facilities, considering its risk.

A Study on the Preparation of Antibacterial Biopolymer Film

  • Cho, Dong-Lyun;Na, Kun;Shin, Eun-Kyung;Kim, Hyun-JIn;Lee, Ki-Young;Go, Jin-Hwan;Choi, Choon-Soon
    • Journal of Microbiology and Biotechnology
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    • v.11 no.2
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    • pp.193-198
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    • 2001
  • Preparation of antibacterial biopolymer film which is suitable for food packaging film was investigated using K-carrageenan as a base material. K-Carrageenan showed good biodegradability and film-forming characteristic but poor mechanical properties under humid condition. Also, various bacteria grew well on its surface. The poor mechanical properties could be improved by mixing with alginate at a 1:1 ratio and crosslinking with $CaCl_2$ solution. Antibacterial property coul be provided by modifying the K-carrageenan film surface with acrylic acid plasma followed by ion-exchange with $Ag^+$ ions. Such prepared film still showed good biodegradability by various fongi.

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Chemical Modification Studies of Yeast Farnesyl Protein Transferase

  • Sohn, Seung-Wan;Jun, Gyo;Yang, Chul-Hak
    • BMB Reports
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    • v.30 no.4
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    • pp.280-284
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    • 1997
  • Phenylglyoxal diethyl pyrocarbonate (DEPC), and 1-cyclohexyl-3-[2-morpholinoethyl]-carbodiimide metho-p-toluenesulfonate (CMC) are modifying reagents specific for arginine, histidine, and aspartate or glutamate, respectively. They were found to inactivate S. cerevisiae farnesyl protein transferase (FPTase). The peptide substrate protected the enzyme against inactivation by CMC and the other substrate farnesyl pyrophosphate showed protection against inactivation by phenylglyoxal. while neither of the two substrates protected the enzyme against DEPC inactivation. These results suggest the presence of aspartate/glutamate, arginine and histidine residues at the active site of this enzyme.

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