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191.
A new ligand incorporating a dioxime moiety, (2E,3E)-3-[(2-{[(1E,2E)-2-(hydroxyimino)-1-methylpropylidene]amino}phenyl)imino]butan-2-one oxime, (H2Phmdo) (3) has been prepared by reacting 2,3-butanedionemono-{O-[4-(1-methyl-2-oxo-propylideneaminooxy)-2,3-bis-(1-methyl-2-oxo-propylideneaminooxy-methyl)-but-2-enyl]-oxime} (2) with 1,2-phenylenediamine. Mono-, di- and trinuclear copper(II) and/or nickel(II) complexes of H2Phmdo were characterized by elemental analyses, magnetic moments, 1H-n.m.r. and 13C-n.m.r., i.r. and mass spectral studies. The mononuclear copper(II) and nickel(II) complexes of H2Phmdo were found to have a 1:1 metal:ligand ratio. Elemental analyses, stoichiometric and spectroscopic data of the metal
complexes indicated that the metal ions are coordinated to the oxime and imine nitrogen atoms (C=N). In the dinuclear complexes,
in which the first Cu(II) or Ni(II) ion was complexed with nitrogen atoms of the oxime and imine groups, the second Cu(II) ion is ligated with dianionic oxygen atoms of the oxime groups and are linked to the 1,10-phenanthroline nitrogen atoms.
The data support the proposed structure of H2Phmdo and its complexes. 相似文献
192.
This article describes the synthesis of a new (2E,3E,6R,9E,11E)-6-isopropenyl-3,6,10-trimethyl-5,8-dioxa-4,9-diazadodeca-3,9-diene-2,11-dione dioxime (H2hmdm), and its mono-, homo, and heterodinuclear copper(II)/nickel(II) complexes. Elemental analyses, stoichiometric and spectroscopic
data of the metal complexes indicated that the metal ions are coordinated to the oxime and imine nitrogen atoms (C=N). The
Cu(H2hmdm), molecule coordinates to the second copper(II) ion through the oximate oxygens to afford a binuclear structure doubly
bridged by the oximate groups in the cis arrangement. In the dinuclear complexes, in which the first CuII ion was complexed with nitrogen atoms of the oxime and imine groups, the second CuII ion is ligated with the 1,10-phenanthroline nitrogen atoms. Ligand and its mononuclear copper(II), homo and heterodinuclear
copper(II)–nickel(II) complexes of (H2hmdm) were characterized by elemental analyses, magnetic moments, 1H-n.m.r. and 13C-n.m.r., i.r., and mass spectral studies. The data support the proposed structure of H2hmdm and its complexes. 相似文献
193.
In the literature, several definitions of a preponderant derivative exist. An old result of Jarník implies that a typical continuous function on has a (strong) preponderant derivative at no point. We show that a typical continuous function on has an infinite (weak) preponderant derivative at each point from a -dense subset of .
194.
Sequential injection extraction based on restricted access material for determination of furosemide in serum 总被引:1,自引:0,他引:1
Huclová J Satínský D Maia T Karlícek R Solich P Araújo AN 《Journal of chromatography. A》2005,1087(1-2):245-251
Restricted access material (RAM) column containing 25 microm C18 alkyl-diol support was integrated into the sequential injection analysis (SIA) manifold and the SIA-RAM system was tested for direct determination of furosemide in serum. LiChrospher ADS column based on restricted access material is proposed to direct injection of biofluids. The integration of RAM material into SIA enabled creation of a comprehensive on-line sample clean-up technique combined with fluorescence quantitation of analyte. Centrifuged and diluted serum sample was aspirated into the system and loaded onto the column using acetonitrile-water (2:98), pH 2.7. The analyte was retained on the column while proteins contained in the sample were removed to the waste without precipitation and clogging the column. Interfering substances complicating the detection were washed out by acetonitrile-water (15:85), pH 2.7 in the next step. The extracted analyte was eluted by means of acetonitrile-water (25:75), pH 2.3 to the fluorescence detector (emission filter 385 nm). The whole procedure comprising sample pre-treatment, analyte detection and column reconditioning took 20 min. The recoveries of furosemide from serum lay between 101.4 and 103.4% for three concentrations of analyte. 相似文献
195.
Agakichiev G Appelshäuser H Baur R Bielcikova J Braun-Munzinger P Cherlin A Drees A Esumi SI Filimonov K Fraenkel Z Fuchs Ch Glässel P Hering G Huovinen P Lenkeit B Marín A Messer F Messer M Milosevic J Miśkowiec D Nix O Panebrattsev Y Petrácek V Pfeiffer A Rak J Ravinovich I Razin S Rehak P Sako H Saveljic N Schmitz W Shimansky S Socol E Specht HJ Stachel J Tilsner H Tserruya I Voigt C Voloshin S Weber C Wessels JP Wurm JP Yurevich V;CERES Collaboration 《Physical review letters》2004,92(3):032301
Elliptic flow and two-particle azimuthal correlations of charged hadrons and high-p(T) pions (p(T)>1 GeV/c) have been measured close to midrapidity in 158A GeV/c Pb+Au collisions by the CERES experiment. Elliptic flow (v(2)) rises linearly with p(T) to a value of about 10% at 2 GeV/c. Beyond p(T) approximately 1.5 GeV/c, the slope decreases considerably, possibly indicating a saturation of v(2) at high p(T). Two-pion azimuthal anisotropies for p(T)>1.2 GeV/c exceed the elliptic flow values by about 60% in midcentral collisions. These nonflow contributions are attributed to nearside and back-to-back jetlike correlations, the latter exhibiting centrality dependent broadening. 相似文献
196.
Nagihan?Saglam Ahmet?Colak Kerim?Serbest Serdar?Karab?cek Saadettin?GünerEmail author 《Monatshefte für Chemie / Chemical Monthly》2004,135(8):1023-1031
Summary. Nucleolytic activities of novel mononuclear Cu(II), homo- and heterodinuclear Cu(II)–Ni(II) complexes with two diester-type ligands were investigated on pCYTEXP by neutral agarose gel electrophoresis. The analyses of the cleavage products obtained electrophoretically indicate that the examined complexes induce very similar conformational changes on supercoiled DNA by converting supercoiled form to nicked form. At concentrations greater than 100M, the complexes possessed effective nucleolytic activities for 10min of incubation time. However, their nucleolytic activities did not increase significantly with longer periods of incubation. The pH-nucleolytic activity profiles of the complexes differed significantly. Metal complex induced DNA cleavage was also tested for inhibition by various radical scavengers. It could be proposed from the data that diffusible intermediate oxidants are not involved in these reactions or they are not necessary for DNA cleavage since none of antioxidants inhibited DNA cleaving activities of the complexes. 相似文献
197.
Golser R Gnaser H Kutschera W Priller A Steier P Wallner A Cízek M Horácek J Domcke W 《Physical review letters》2005,94(22):223003
The existence of (metastable) molecular hydrogen anions H2(-), D2(-), and H3(-) is demonstrated. These anion species were produced by sputtering of TiH2 and TiD2 targets with Cs+ ions and were identified by accelerator mass spectrometry. From the respective flight times through the spectrometer, lifetimes for H2(-) and D2(-) of at least 3 micros and 4 micros, respectively, can be inferred. Theoretical calculations within the nonlocal resonance model predict the existence of highly rotationally excited anions with lifetimes in the micros range. It is proposed that in sputtering molecular hydrogen species with high rotational and vibrational excitation are formed that are stable on the time scale of the experiment. 相似文献
198.
Potentiometric determination of iron with DTPA at pH 1.6 (platinum and calomel electrodes) permits determination of iron in the presence of aluminium up to an Al:Fe ratio of 70. Aluminium is determined indirectly by addition of excess of DCTA, adjustment to pH 5, and back-titration with iron(III) chloride. 相似文献
199.
P. Kubícek 《Czechoslovak Journal of Physics》1970,20(4):475-486
The paper deals with equations of motion of ions in a time-dependent magnetic field of a solenoid. These lead to a Hill equation approximated by a Mathieu equation. The instability of solutions of these equations in certain regions implies a theoretical possibility of filtering ion beams according to masses. 相似文献
200.
Two methods for the determination of adenosine deaminase and purine nucleoside phosphorylase activities were compared. The high-performance liquid chromatographic (HPLC) technique used separation on a reversed-phase silica column and exhibited adequate sensitivity and a markedly higher rate of analysis compared with that of the paper radiochromatographic method. Correlation analysis of the results obtained by the two methods on a set of lymphoid cells from 25 patients with lympho-proliferative disorders confirmed the utility of the HPLC technique in clinical investigations. 相似文献