• Title/Summary/Keyword: Metallic Ions

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Morphology of RF-sputtered Mn-Coatings for Ti-29Nb-xHf Alloys after Micro-Pore Form by PEO

  • Park, Min-Gyu;Park, Seon-Yeong;Choe, Han-Cheol
    • Proceedings of the Korean Institute of Surface Engineering Conference
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    • 2016.11a
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    • pp.197-197
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    • 2016
  • Commercially pure titanium (CP Ti) and Ti-6Al-4V alloys have been widely used for biomedical applications. However, the use of the Ti-6Al-4V alloy in biomaterial is then a subject of controversy because aluminum ions and vanadium oxide have potential detrimental influence on the human body due to vanadium and aluminum. Hence, recent works showed that the synthesis of new Ti-based alloys for implant application involves more biocompatible metallic alloying element, such as, Nb, Hf, Zr and Mo. In particular, Nb and Hf are one of the most effective Ti ${\beta}-stabilizer$ and reducing the elastic modulus. Plasma electrolyte oxidation (PEO) is known as excellent method in the biocompatibility of biomaterial due to quickly coating time and controlled coating condition. The anodized oxide layer and diameter modulation of Ti alloys can be obtained function of improvement of cell adhesion. Manganese(Mn) plays very important roles in essential for normal growth and metabolism of skeletal tissue in vertebrates and can be detected as minor constituents in teeth and bone. Radio frequency(RF) magnetron sputtering in the various PVD methods has high deposition rates, high-purity films, extremely high adhesion of films, and excellent uniform layers for depositing a wide range of materials, including metals, alloys and ceramics like a hydroxyapatite. The aim of this study is to research the Mn coatings on the micro-pore formed Ti-29Nb-xHf alloys by RF-magnetron sputtering for dental applications. Ti-29Nb-xHf (x= 0, 3, 7 and 15wt%, mass fraction) alloys were prepared Ti-29Nb-xHf alloys of containing Hf up from 0 wt% to 15 wt% were melted by using a vacuum furnace. Ti-29Nb-xHf alloys were homogenized for 2 hr at $1050^{\circ}C$. Each alloy was anodized in solution containing typically 0.15 M calcium acetate monohydrate + 0.02 M calcium glycerophosphate at room temperature. A direct current power source was used for the process of anodization. Anodized alloys was prepared using 270V~300V anodization voltage at room. Mn coatings was produced by RF-magnetron sputtering system. RF power of 100W was applied to the target for 1h at room temperature. The microstructure, phase and composition of Mn coated oxide surface of Ti-29Nb-xHf alloys were examined by FE-SEM, EDS, and XRD.

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Studies on the Hesperidinase of Aspergillus niger S-1 (Aspergillus niger S-1이 생산하는 Hesperidin 분해효소에 관한 연구)

  • 기우경
    • Microbiology and Biotechnology Letters
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    • v.4 no.4
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    • pp.131-137
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    • 1976
  • Aspergillus niger S-1 was proved to be a good hesperidinase producer which have been selected for naringinase utilization. Enzyme of this strain had good characteristics and purified relative high degree with good recovery by ammonium sulfate or aceton treatment. Results obtained were summarized as follows (1) The enzyme was most active at 60$^{\circ}C$, when the reaction was performed in the pH 4.0 for 30min. Optimum pH for enzyme activity was 5.0 and activity was retained 78% at pH value 3.5. (2) Hesperidinase activity retained 95% of its full activity after treatment at 60$^{\circ}C$ for 30min at pH value 4.0., 70% at 70$^{\circ}C$ and 65% at 80$^{\circ}C$. Most stable pH of this enzyme was showed 5.0 after treatment for 24hr at 4$^{\circ}C$ (3) Only Magnesium ion activated enzyme reaction, while other metallic ions, Cu$\^$++/, Mn$\^$++/, Pb$\^$++/, Mo$\^$++/, Ag$\^$++/, Hg$\^$++/ inhibited. (4) Eleven fold purification with 35% recovery was obtained in the case of 60% aceton treatment and 10-fold purification with 5.6% recovery was showed with 40% aceton comparing to the crude extract Enzyme. (5) Crude enzyme precipitated with 0.4-0.6 saturated ammonium sulfate contained 13f6 of the original enzyme activity with 48-fold increase in specific activity and enzyme has been purified 25 fold with a yield 19% by 0.6-5.8 saturation. (6) Hesperidinase formation was noticeably increased by addition of small amount of orange-peel extraction on the wheat bran medium.

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A Study of the Bio-Nutritional Evaluation of Duck-Meat (오리고기의 영양생화학적 가치에 관한 연구)

  • Lee, Yong-Ock;Nam, Hyun-Keun
    • Journal of Nutrition and Health
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    • v.14 no.1
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    • pp.16-25
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    • 1981
  • Commercially available duck-meat was subjected to proximate analysis. On a wet basis, the duck-meat contained 62.87, 17.05, 19.06 ana 1.02 percent of moisture, crude fat, crude protein and ash, respectively. Almost all the essential amino acids contained in the duck-meat protein, ana the tryptophan was the limiting one by amino acid analysis of GLC. An analysis of the fatty acid composition by GLC showed a relatively high concentration of oleic acid. There was also a considerable content of linoleic acid. The content of polyunsaturated fatty acids of duck-meat was 70.9% and the P/S ratio of fatty acids was 3.4. The cholesterol content in duck-meat was determined to be approximately 70. 5mg/100g ofm sample. According to blood analysis, it was understood that the content of phospholipids was relatively high, particulary in lecithin. ATP-phosphorus, at the higher temperature, was released faster than at the lower temperature, by two hours after postmortem. The ATPase activity of Myogibril was inhibited at the relatively high concentration of added EDTA and metallic ions, but the activity was very high in the lower concentrations. According to the cooking conditions, boiled duck-meat showed good digestion by pepsin. It was understood that the digestibility of duck meat was relatively high, so the duck-meat protein is good source of animal protein. Therefore, it is able to be recommended that duck-meat is good nitrogen source animal food.

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Interfacial Adhesion and Reliability between Epoxy Resin and Polyimide for Flexible Printed Circuit Board (연성인쇄회로기판의 에폭시수지와 폴리이미드 사이의 계면접착력 및 신뢰성 평가)

  • Kim, Jeong-Kyu;Son, Kirak;Park, Young-Bae
    • Journal of the Microelectronics and Packaging Society
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    • v.24 no.1
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    • pp.75-81
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    • 2017
  • The effects of KOH pretreatment and annealing conditions on the interfacial adhesion and the reliability between epoxy resin and polyimide substrate in the flexible printed circuit board were quantitatively evaluated using $180^{\circ}$ peel test. The initial peel strength of the polyimide without the KOH treatment was 29.4 g/mm and decreased to 10.5 g/mm after 100hrs at $85^{\circ}C/85%$ R.H. temperature/humidity treatment. In case of the polyimide with annealing after KOH treatment, initial peel strength was 29.6 g/mm and then maintained around 27.5 g/mm after $85^{\circ}C/85%$ R.H. temperature/humidity treatment. Systematic X-ray photoelectron spectroscopy analysis results showed that the peel strength after optimum annealing after KOH treatment was maintained high not only due to effective recovery of the polyimide damage by the polyimide surface treatment process, but also effective removal of metallic ions and impurities during various wet process.

Synthesis and Structural Analysis of Binary Alloy ($MoRu_3$, $MoRh_3$) (이성분계 금속합금($MoRu_3$, $MoRh_3$)의 합성 및 구조분석)

  • Park, Yong Joon;Lee, Jong-Gyu;Kim, Jong Goo;Kim, Jung Suk;Jee, Kwang-Yong
    • Analytical Science and Technology
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    • v.11 no.3
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    • pp.189-193
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    • 1998
  • Binary alloys, $MoRu_3$ and $MoRh_3$, have been prepared using arc melting furnace. Mo and the noble metals Ru and Rh are the constituents of metallic insoluble residues, which were found in the early days of the post-irradiation studies on uranium oxide fuels. Detailed structural informations about these alloys have not been reported on JCPDS files of ICDD (International Centre for Diffraction Data). The results of X-ray diffraction study showed that the alloy was crystallized in hexagonal close-packing, well known as ${\varepsilon}$-phase. The X-ray diffraction patterns of these alloys matched well to that of $WRh_3$ with $P6_3/mmc$ of space group. The lattice parameters, a and c, were calculated using the least squares extrapolation. It was found from X-ray photoelectron spectroscopic measurements that Mo on the surface of the alloy was oxidized to Mo(6+), which could be removed by sputtering with Ar ions for approximately 15 minutes. The changes in binding energy of Mo, Ru, and Rh on the surface of the alloy were not observed. Magnetic susceptibility measurements resulted in the typical Pauli-paramagnetic behavior in the temperature range of 2 to 300 K.

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Characterization of a Fibrinolytic Enzyme from Pickled Anchovy (멸치젓갈유래의 혈전용해호소에 대한 특성)

  • Yang Woong-Suk;Lim Hak-Seob;Chung Kyung Tae;Kim Young-Hee;Huh Man Kyu;Choi Byung Tae;Choi Yung Hyun;Jeong Yong Kee
    • Journal of Life Science
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    • v.15 no.3 s.70
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    • pp.434-438
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    • 2005
  • In the previous study, we isolated a myulchikinase (MK), which has fibrinolytic activity and cytotoxicity to the tumor cell line, from myl- chi-jeot-gal. In this study, the effect of NaCl concentration, metallic ions, pH, temperature, and plasminogen on the activity of MK was analysed. The MK activity was maintained at least $80\%$ activity up to $30\%$ NaCl, which indicates that the enzyme may be halotolerant. The optimal pH and temperature were 8 and $40^{\circ}C$, respectively. The fibrinolytic activity of MK was completely inhibited with 0.5 mM $Hg^{2+}$ and inhibited to $50^{\circ}C$ with 1 mM $Cu^{2+}\;and\;Zn^{2+}$. The MK showed strong activity in plasminogen- rich fibrin plate but not in plasminogen-free fibrin plate. The result indicates that the MK may be a plasminogen activator type fibrinolytic enzyme.

A Potent Tissue Destructive Activity of Secreted Proteins of Aeromonas hydrophila (조직 괴사 활성을 지닌 Aeromonas hydrophila 의 분비 단백질에 관한 연구)

  • Kim, Kyu Lee;Choe, Yunjeong;Kang, Ho Young
    • Journal of Life Science
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    • v.25 no.2
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    • pp.214-222
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    • 2015
  • Aeromonas hydrophila is the most common water fish pathogen and cause diseases such as hemorrhagic septicemia, dropsy, ulceration and asymptomatic septicemia. A. hydrophila secretes many extracellular products (ECPs) which contribute to effective infection, wide distribution and great adaptability to environmental changes. Crude ECPs of A. hydrophila CK257, a strain used in this study, exhibits a toxic activity to the animals including mouse, rabbit and fish. Toxic symptoms were indicated by tissue damage and skin injuries in animal. When ECPs were subcutaneously injected to animals, skin damages were observed, appearing like necrosis. Preliminary research demonstrated that the active factors are protein component. The crude ECPs were collected after ammonium sulfate precipitation of cell-free culture supernatant. ECPs were fractionated with the use gel filtration chromatography. Five ECP fractions were obtained, of which one fraction was found to be toxic to goldfish. MALDI-TOF analyses provided two interesting proteases called M35 and M28. Both M35 and M28 are known as metalloprotease. Accordingly, proteins in an active fraction exhibited caseinolytic activity. These proteins were difference of caseinolytic activity under different metallic ions. Also active fraction has elastolytic activity. These results suggested that peptidase M28 and M35 may be a candidate factor for tissue necrosis activity about infection with A. hydrophila.

Soft X-ray Synchrotron-Radiation Spectroscopy Study of [Co/Pd] Multilayers as a Function of the Pd Sublayer Thickness (Pd층의 두께 변화에 따른 [Co/Pd] 다층박막의 연엑스선 방사광 분광 연구)

  • Kim, D.H.;Lee, Eunsook;Kim, Hyun Woo;Seong, Seungho;Kang, J.-S.;Yang, Seung-Mo;Park, Hae-Soo;Hong, JinPyo
    • Journal of the Korean Magnetics Society
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    • v.26 no.4
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    • pp.124-128
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    • 2016
  • We have investigated the electronic structures of intermetallic multilayer (ML) films of [$Co(2{\AA})/Pd(x{\AA})$] (x: the thickness of the Pd sublayer; x = $1{\AA}$, $3{\AA}$, $5{\AA}$, $7{\AA}$, $9{\AA}$) by employing soft X-ray absorption spectroscopy (XAS) and soft X-ray magnetic circular dichroism (XMCD). Both Co 2p XAS and XMCD spectra are found to be similar to one another, as well as to those of Co metal, providing evidence for the metallic bonding of Co ions in [Co/Pd] ML films. By analyzing the measured Co 2p XMCD spectra, we have determined the orbital magnetic moments and the spin magnetic moments of Co ions in [$Co(2{\AA})/Pd(x{\AA})$] ML films. Based on this analysis, we have found that the orbital magnetic moments are enhanced greatly when x increases from $1{\AA}$ to $3{\AA}$, and then do not change much for $x{\geq}3{\AA}$. This finding suggests that the interface spin-orbit coupling plays an important role in determining the perpendicular magnetic anisotropy in [Co/Pd] ML films.

Influence of Septic in Vibrio Vulnificus from Phytic Acid (피틴산(Phytic acid)이 비브리오(Vibrio vulnificus) 패혈증에 미치는 영향)

  • Chung, Young-Ho;Cho, Chun-Hwi;Lee, Sun-Woo;Lim, Chi-Hwan
    • Korean Journal of Agricultural Science
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    • v.32 no.1
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    • pp.71-80
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    • 2005
  • Phytic acid chelates excellently the metallic ions and the positive ions, especially has high affinity with $Fe^{2+}$ and $Ca^{2+}$. Merits of phytic acid can be taked in easily, edibile and harmless to body, so it was investigated that phytic acid can be substituted for EDTA in this study. 1. The Intensificative effect of chelating agent and disinfective osmotic shock of Vibrio vulnificus The number of initial existent fungi measured $1.7{\times}10^6$. The percentages of the survival fungi against the osmotic shock by distillated water were calculated at 1 minute, 3 minute and 5 minute after inoculation. The percentages of the survival fungi in $Mg^{2+}$ were 92.5%, 91.8% and 79.8% at each time, the average percentage was 88%. Also the sudden extinction was observed around 1 minute after inoculation and the survival fungi were not observed from 3 through 5 minute in spite of repeated experimentation. 2. Influence of Vibrio vulnificus on the survival of the mice. The first mouse started to die in 180 minute after inoculation in case that the inoculating number was $2.3{\times}10^7cfu/ml$. All died within 4.5 hour. The average of survival time was 226 minute. The first mouse started to die in 228 minute after inoculation in case that the inoculating number was $0.8{\times}10^6cfu/ml$. All died within 5 hour. The average of survival time was 300 minute and the survival time was 1.3 times high. The tendencies of death in two cases were similar, but the fatal rate were largely dependent on inoculating number.

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Uronic Acid Composition, Block Structure and Some Related Properties of Alginic Acid (4) On Alginic Acid from Myagropsis myagroides Fensholt and Sargassum horneri C. Agardh (알긴산의 화학적 조성 및 그 물성에 관한 연구 (4) 외톨개모자반 및 괭생이모자반의 알긴산)

  • KIM Dong-Soo;PARK Yeung-Ho
    • Korean Journal of Fisheries and Aquatic Sciences
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    • v.18 no.2
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    • pp.124-130
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    • 1985
  • In the previous papers (Kim and Park, 1984 a, b; 1985 a), we have reported on alginic acid from Ecklonia cava and Sargassum ringgoldianum. The seasonal variation in the composition of uronic acids and their block structures of alginic acid from Myagropsis myagroides Fensholt and Sargassum horneri C. Agardh (collected from Iee Chun village on the coast of Ilgwang-myon, Yansan-gun, Kyungnam, Korea, in the period of January to December in 1982) are investigated, and their relationship between the chemical composition and some related properties are discussed in this study. One year average contents of alginic acid were $25.2\%$ in the M. myagroides and $26.5\%$ in the S. horneri, and one year average values of M/G ratios were 1.97 in the M. myagroides and 1.38 in the S. horneri. The value of M. myagroides was largest in the period of December to April, and smallest in May to June and October to November. The value of S. horneri was largest in January and smallest in March to April. The proportion of alternating, M and G block in M. myagroides were $18.4\%,\;40.4\%$, and $41.2\%$, and those in S. horneri $9.8\%,\;33.3\%$ and $56.9\%$, respectively. The higher viscosity showed the value of 45.3 cP in M. myagroides (in November), and 26.0 cP in S. horneri(in January), respectively. Furthermore, the dependence on temperature of M. myagroides alginic acid was also larger in November, that of S. horneri alginic acid in June. Ion exchange ability of M. myagroides alginic acid was highest in November and the exchange amounts were $Pb^{2+}\;4.4,\;Cu^{2+}\;1.8,\;Zn^{2+}\;2.5$ and $Co^{2+}\;2.0\;meq/g$. Na-Alg., and the ability of S. horneri alginic acid was highest in June and the amounts were $Pb^{2+}\;4.5,\;Cu^{2+}\;2.2,\;Zn^{2+}\;2.4$ and $Co^{2+}\;2.1\;meq/g.$ Na-Alg. The affinity with metallic ions appeared higher in order of $Pb^{2+}>Cu^{2+}>Zn^{2+}>Co^{2+}$, and the exchange ability assumed to relate with the block ratio of uronic acid.

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