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Preliminary Study on the Visualization and Quantification of Elemental Compositions in Individual Microdroplets using Solidification and Synchrotron Radiation Techniques

  • Ma, Chang-Jin;Tohno, Susumu;Kasahara, Mikio
    • Asian Journal of Atmospheric Environment
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    • v.5 no.1
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    • pp.56-63
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    • 2011
  • Quantifying the solute composition of a cloud droplet (or a whole droplet) is an important task for understanding formation processes and heating/cooling rates. In this study, a combination of droplet fixation and SR-XRF microprobe analysis was used to visualize and quantify elements in a micro-scale droplet. In this study, we report the preliminary outcome of this experiment. A spherical micro-scale droplet was successfully solidified through exposure to ${\alpha}$-cyano-acrylate vapor without affecting its size or shape. An X-ray microprobe system equipped at the beam line 37XU of Super Photon ring 8 GeV (SPring-8) was applied to visualize and quantify the elemental composition in an individual micro-scale droplet. It was possible to reconstruct 2D elemental maps for the K and Cl contained in a microdroplet that was dispensed from the 10-ppm KCl standard solution. Multi-elemental peaks corresponding to X-ray energy were also successfully resolved. Further experiments to determine quantitative measures of elemental mass in individual droplets and high-resolution X-ray microtomography (i.e., 3D elemental distribution) are planned for the future.

Corrosion Behavior and Oxide Film Formation of T91 Steel under Different Water Chemistry Operation Conditions

  • Zhang, D.Q.;Shi, C.;Li, J.;Gao, L.X.;Lee, K.Y.
    • Corrosion Science and Technology
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    • v.16 no.1
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    • pp.8-14
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    • 2017
  • The corrosion behavior of a ferritic/martensitic steel T91 exposed to an aqueous solution containing chloride and sulfate ions is investigated depending on the stimulated all-volatile treatment (AVT) and under oxygenated treatment (OT) conditions. The corrosion of T91 steel under OT condition is severe, while the corrosion under AVT condition is not. The co-existence of chloride and sulfate ions has antagonistic effect on the corrosion of T91 steel in both AVT and OT conditions. Unlike to corrosion resistance in the aqueous solution, OT pretreatment provides T91 steel lower oxidation-resistance than VAT pretreatment. From scanning electron microscopy/energy dispersive X-ray spectroscopy (SEM/EDS) and X-ray diffraction (XRD) analysis, the lower corrosion resistance in the aqueous solution by VAT conditions possibly is due to the formation of pits. In addition, the lower oxidation resistance of T91 steel pretreated by OT conditions is explained as follows: the cracks formed during the immersion under OT conditions accelerated peeling-off rate of the oxide film.

Untersuchungen Zur Herstellung Von Neun Messpraparaten Fur Die Rontgenfluoreszenzspektrometrie (X-線 螢光分析에 있어서의 새로운 試料 調制에 關한 硏究)

  • Park, Yung-Kyu
    • Journal of the Korean Chemical Society
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    • v.11 no.4
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    • pp.165-169
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    • 1967
  • Eine neue Methode zur Herstellung von Meßpraparation wird die Bestimmng der Spurenelemente Quecksilber, Kupfer, Blei, Zink, Nickel, Kobalt und Eisen durch Rontgenflureszenzspektrometrie entwickelt. Die Spurenelemente werden aus waßrigen Losungen durch Einleitung von Schwefelwasserstoff mit Aluminiumsulfat als Trager bei pH8 ausgefallt. Die Niederschlage der Metallsulfide werden uber Membranfilter filtriert, mit Gelatine fixiert und ihre Absolutmengen durch Rontgenfluoreszenz analyse bestimmt. Bei der geringen Dicke der auszumessenden Schichten treten Matrixeffekte nicht auf. Durch den Zusatz von Aluminiumsulfat-Trager wird eine gute Reproduzierbarkeit erzielt: Quecksilber, Kupfer, Blei, Zink, Nickel und Kobalt werden bei einer Konzentration von 50 bis 1000 p.p.b. mit einer relativen Standard-abweichung von 5.0% und Eisen bei einer Konzentration von 50∼1000 p.p.d. mit einer relativen Standardabweichung von 6.1% gemessen.

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Study for Electro-optic Properties of PZT Ceramics (PZT 세라믹의 전기광학적 특성에 관한 연구)

  • Kim Si-Joong;Kim Kun;Ahn Byeung-Joon
    • Journal of the Korean Chemical Society
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    • v.36 no.1
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    • pp.51-56
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    • 1992
  • X-ray diffraction analysis and infrared spectrophotometry were used to investigate the crystal structures and the bonding characteristics in $Pb(Zr_{1-y}Ti_y)O_3$ (PNZT), which has a perovskite structure. As $Pb^{2+}$ of PZT was substituted by 8${\sim}$12 atom% $Nd^{3+}$ ion, the structures were changed to cubic from tetragonal and its transmission had maximum value. Transmission increased as the stretching force constant $(k_s)$ of unit cell increased. It is supposed that the electro-optic characteristics might occur due to electron-transition from HOMO to LUMO of titanium ion.

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Studies on Selection of Less Toxic Insecticides for the Aerial Control of Pine Needle Gall Midge (Thecodiplosis) japonensis Uchida et Inouye) (솔잎혹파리 항공방제용 저독성 농약선발연구)

  • 이형래;변병호
    • Korean journal of applied entomology
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    • v.33 no.3
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    • pp.201-206
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    • 1994
  • Trunk implantation method of phosphamidon 50% Lq.is commonly applied to control the pine needle gall midge (Thecodiplosis laponensts Uchida et Inouye) Since trunk implantaion is normally practiced during the late Spring, it is often difficult to accommodate necessay labor in mral area. As an alternative, aerial spraylng of less toxic ~nsecticide was designed. Usage of less toxic insecticide in the aenal control of pine needle gall midge can reduce the damage to forest ecosystem. The buproferin, one of the insect growth regulator, was selected at d~fferent rate of dilutions and the treatments effects ruere evaluated at different date and time When 50 t~mes diluted solution of buprofezin 40% SC was treated on different period, there was no significant difference in dficacies. the control efficacies of buproferin 40% SC was measured by occurrences (%) of gall formation of the pine needle gall midge using a ultra low volume (ULV) sprayer and the dilutions of 10X 30X and 50X of buprofez~n 40% SC gave efficacies. 72.4. 57.6 and 8.4, respectively.

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Die Bestimmung von Spurenelementen in Naurlichen Wassern durch Rontgenfluoreszenzspektrometrie nach Konzentration durch Verdampfen (Ⅰ) (X-線螢光分析에 依한 天然水中의 微量金屬定量 [I] 蒸發濃縮에 依하여)

  • Yung Kyu Park
    • Journal of the Korean Chemical Society
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    • v.13 no.1
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    • pp.41-44
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    • 1969
  • Eine neuentwickelte Methode zur Herstellung von Me${\ss}$praparaten wird fur die Bestmmung der Spurenelemente in Wasser Rontgenfluroreszspektrometrie angewendet. Supuren von Kupfer, Blei, Zink, Nickel, Kobalt und Eisen werden aus großen Mengen von naturlichem Wasser durch Verdampfen konzentriert. Aus der konzentrierten Losung werden die Spurenelemente durch Einleitung von Schwefelwasserstoff bei pH 8 unter Zusatz von Aluminiumsulfat-Trager ausgefallt. Die Niederschlage der Metallsulfide werden durch Membranfilter filtriert, mit Gelatine fixiert und ihre Absolutmengen durch Rontgenfloreszenzanalyze bestimmt. Kupfer, Blei, Zink, Nickel, Kobalt und Eisen werden bei einer Konzentration von 2.5 bis 50.0 p.p.b. mit einer relativen Standardabweichung 14.0% gemesser.

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Highly Selective and Simple Zero and First Order Derivative Spectrophotometric Determination of Palladium by Using α-Benzilmonoxime in Triton X-100 Micellar Solution

  • Eskandari, Habibollah;Karkaragh, Gholamhassan Imanzadeh
    • Bulletin of the Korean Chemical Society
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    • v.24 no.12
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    • pp.1731-1736
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    • 2003
  • The reaction of ${\alpha}$-Benzilmonoxime with palladium(II) produces a green complex in triton X-100 micellar media. Palladium has been determined using zero and first derivative spectrophotometric methods. The absorbances of Pd(II)- ${\alpha}$--benzilmonoxime complex at 441.8 and 677.0 nm in 0.10 M perchloric acid solution were monitored and linear working ranges of 0.3-12.0 and 0.7-20 ${\mu}$g mL$^{-1}$ with detection limits of 0.07 and 0.10 ${\mu}$g $mL^-1$ were obtained, respectively. Also, recoveries in the range of 92.8 to 100.1% and relative standard deviations in the range of 0.4 to 7.1% were obtained. First derivative spectrophotometry has also been applied for palladium determination under the optimum condition. The linear dynamic range of 0.2-24.0 ${\mu}$g $mL^{-1}$ palladium with relative standard deviations of 0.6-6.9% and recoveries in the range of 94.9-102.5% has been obtained by first derivative spectrophotometry. The method shows high selectivity because of the high concentration of acid used, which prevents formation of complexes of ${\alpha}$--benzilmonoxime with the other cations. The palladium complex formed was stable at least one day. The method was successfully applied to the determination of palladium in some synthetic palladium alloys and palladium-charcoal powder.

HQNO-sensitive NADH:Quinone Oxidoreductase of Bacillus cereus KCTC 3674

  • Kang, Ji-Won;Kim, Young-Jae
    • BMB Reports
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    • v.40 no.1
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    • pp.53-57
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    • 2007
  • The enzymatic properties of NADH:quinone oxidoreductase were examined in Triton X-100 extracts of Bacillus cereus membranes by using the artificial electron acceptors ubiquinone-1 and menadione. Membranes were prepared from B. cereus KCTC 3674 grown aerobically on a complex medium and oxidized with NADH exclusively, whereas deamino-NADH was determined to be poorly oxidized. The NADH oxidase activity was lost completely by solubilization of the membranes with Triton X-100. However, by using the artificial electron acceptors ubiquinone-1 and menadione, NADH oxidation could be observed. The activities of NADH:ubiquinone-1 and NADH:menadione oxidoreductase were enhanced approximately 8-fold and 4-fold, respectively, from the Triton X-100 extracted membranes. The maximum activity of FAD-dependent NADH:ubiquinone-1 oxidoreductase was obtained at about pH 6.0 in the presence of 0.1M NaCl, while the maximum activity of FAD-dependent NADH:menadione oxidoreductase was obtained at about pH 8.0 in the presence of 0.1M NaCl. The activities of the NADH:ubiquinone-1 and NADH:menadione oxidoreductase were very resistant to such respiratory chain inhibitors as rotenone, capsaicin, and $AgNO_3$, whereas these activities were sensitive to 2-heptyl-4-hydroxyquinoline-N-oxide (HQNO). Based on these results, we suggest that the aerobic respiratory chain-linked NADH oxidase system of B. cereus KCTC 3674 possesses an HQNO-sensitive NADH:quinone oxidoreductase that lacks an energy coupling site containing FAD as a cofactor.

Measurements of optical nonlinear refractive index through the Z-scan method with circular symmetric beam (원형대칭 빛살 Z-스캔 방법에 의한 광학적 비선형 굴절율 측정)

  • Kim, Gi-Hun;Im, Yong-Sik;Park, Jong-Dae;Kim, Chil-Min;Jo, Chang-Ho
    • The Journal of Natural Sciences
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    • v.7
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    • pp.11-17
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    • 1995
  • The optical nonlinear refractive index of $Bil_3$ semiconductor microcluster colloid has been measured by the Z-scan method with circular symmetric beam. The value of nonlinear refractive index was -1.53 x $10^12($cm^2/W) at $0.532\mum$and the nonlinearities were mainly due to thermal effect induced by 20 ns laser pulse. And the absorption coefficient was measured to be -$10^8$(cm/W)

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Structure of Tetrapropionyloxycalix[4]arene (Tetrapropionyloxycalix[4]arene의 구조에 관한 연구)

  • 박영자;김현희
    • Korean Journal of Crystallography
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    • v.6 no.2
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    • pp.80-87
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    • 1995
  • The structure of Tetrapropionyloxycalix[4]arene(C40H40O8) has been studied by X-ray diffraction method. The crystal is monoclinic a=13.921(3), b=13.552(2), c=19.840(5)Å, β=110.38(2)°, Z=4 T=297K, Dc=1.23gcm-3, F(000)=1376, Systematic absences : hkl none, h0l : h+l=2n, 0k0: k=2n define space group P21/n. The structure was solved by direct method and refined by full-matrix least-squares methods to final R of 0.06 for 2514 observed reflections. The macrocycle exists in partial cone conformation. Three propionyl groups direct toward the exterior of the macrocycle cavity.

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