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101.
Mehrzia Krimi Ammar Tahar Jouini Ahmed Driss 《Journal of chemical crystallography》2000,30(4):265-268
The synthesis and crystal structure of a new three dimensional cobalt(II) complex [Co(C6H12N4)2(H2O)4Co(H2O)6][SO4]2.6H2O are reported. It crystallizes in the triclinic space group P-1 with a = 13.394(3), b = 16.077(3), c = 9.282(2) Å, = 89.71(2), = 90.42(2), = 114.02(2)°, V = 1825.6(7)Å3 and Z = 2. The structure is comprised of [Co(C6H12N4)2 (H2O)4Co(H2O)6][SO4]2 units and H2O molecules. Two molecules of ligand and four molecules of water chelate one type of CoII in an octahedral fashion through two N and four O atoms: the four O atoms form the equatorial plane and the two N atoms occupy the apical positions. The other type of CoII cation is chelated by six water molecules. 相似文献
102.
Ammar Sarem Bogdan J. Kowalski Elias Al-Khoury Nehme 《Journal of Electron Spectroscopy and Related Phenomena》2007,160(1-3):58-61
The electronic structures of Cd0.88Fe0.12Se and CdSe have been investigated by photoemission yield spectroscopy (PYS) in the photon energy range from 5 to 12 eV. The () surfaces were obtained by cleavage under ultrahigh vacuum (UHV) conditions. An Fe-related emission appeared at 0.58 eV above the valence band edge. The freshly cleaved surface of Cd0.88Fe0.12Se interacted with ambient atmosphere more strongly than CdSe crystal. Leaving the sample in an UHV chamber at room temperature enabled us to identify surface related features and to observe decrease of the ionization energy Ei, energy threshold Ed and the crystal affinity χ due to change of the surface conditions. Effective density of states, derived from the experimental spectra of Cd0.88Fe0.12Se exhibits, in contrast with CdSe, a surface-related feature degenerated with the bulk valence band. 相似文献
103.
Brandenburg G Ershov A Gao YS Kim DY Wilson R Browder TE Li Y Rodriguez JL Yamamoto H Bergfeld T Eisenstein BI Ernst J Gladding GE Gollin GD Hans RM Johnson E Karliner I Marsh MA Palmer M Plager C Sedlack C Selen M Thaler JJ Williams J Edwards KW Janicek R Patel PM Sadoff AJ Ammar R Bean A Besson D Davis R Kwak N Zhao X Anderson S Frolov VV Kubota Y Lee SJ Mahapatra R O'Neill JJ Poling R Riehle T Smith A Stepaniak CJ Urheim J Ahmed S Alam MS Athar SB Jian L Ling L Saleem M Timm S Wappler F 《Physical review letters》2000,85(15):3095-3099
Using 13.4 fb(-1) of data collected with the CLEO detector at the Cornell Electron Storage Ring, we have observed 300 events for the two-photon production of ground-state pseudoscalar charmonium in the decay eta(c)-->K(0)(S)K-/+pi(+/-). We have measured the eta(c) mass to be [2980.4+/-2.3 (stat)+/-0.6 (syst)] MeV and its full width as [27.0+/-5.8 (stat)+/-1.4 (syst)] MeV. We have determined the two-photon partial width of the eta(c) meson to be [7.6+/-0.8 (stat)+/-0.4 (syst)+/-2.3 (br)] keV, with the last uncertainty associated with the decay branching fraction. 相似文献
104.
R. Ammar D. Coppage R. Davis N. Kwak R. Riemer R. Stump H. Kautzky W. Smart S. Velen L. Voyvodic V. Ammosov V. Baranov A. Belkov V. Gapienko V. Klyukhin V. Koreshev P. Pitukhin V. Sirotenko R.J. Wilkes 《Physics letters. [Part B]》1980,94(1):118-122
An event representing the production and decay of the charmed F+ meson has been identified by means of a 3-constraint fit to decay hypothesis F+ → π+π+π?π0, in which both γ-rays from the π0 converted. The event was produced by a charged current νμ interaction in an emulsion stack located inside the Fermilab 15-foot bubble chamber. The F+ traveled 50 μm, corresponding to a proper time of 1.4 × 10?13 seconds, before decaying in flight. Its mass was determined to be 2017 ± 25MeV. 相似文献
105.
Browder TE Li Y Rodriguez JL Yamamoto H Bergfeld T Eisenstein BI Ernst J Gladding GE Gollin GD Hans RM Johnson E Karliner I Marsh MA Palmer M Plager C Sedlack C Selen M Thaler JJ Williams J Edwards KW Janicek R Patel PM Sadoff AJ Ammar R Bean A Besson D Davis R Kwak N Zhao X Anderson S Frolov VV Kubota Y Lee SJ Mahapatra R O'Neill JJ Poling R Riehle T Smith A Stepaniak CJ Urheim J Ahmed S Alam MS Athar SB Jian L Ling L Saleem M Timm S Wappler F Anastassov A Duboscq JE Eckhart E Gan KK Gwon C 《Physical review letters》2001,86(14):2950-2954
We report results of a search for B-->tau(nu) in a sample of 9.7 x 10(6) charged B meson decays. We exclusively reconstruct the companion B decay to suppress background. We set an upper limit on the branching fraction B(B-->tau(nu))<8.4 x 10(-4) at 90% confidence level. We also establish B(B+/--->K+/-nu(nu))<2.4 x 10(-4) at 90% confidence level. 相似文献
106.
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108.
New dimeric Schiff base quinoline complexes: Synthesis,spectral characterization,electrochemistry and cytotoxicity
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A novel Schiff base ligand (H‐DPPMHQ) derived from 2‐hydrazineylquinoline and 1,3‐diphenyl‐1H‐pyrazole‐5‐carbaldehyde and its dimeric complexes with compositions [Cr(DPPMHQ)Cl]2?2Cl and [M(DPPMHQ)Cl]2 (where M = Cu(II), Co(II), Ni(II) and Zn(II)) have been synthesized and characterized using physicochemical methods like elemental analysis, magnetic susceptibility and molar conductivity measurements, multispectral techniques and electrochemical studies. The molar conductance data reveal that all metal chelates are non‐electrolytes, except the Cr(III) complex which shows a ΛM value of 146.82 Ω?1 cm2 mol?1, indicating that it is a 1:2 electrolyte. Infrared spectral results show that the metal is organized through four nitrogen atoms (azomethine and deprotonated imine groups, pyrazole and quinoline rings) besides chlorine atoms. The NH proton is also displaced during complexation, as indicated by 1H NMR spectral data. Based on the electron spin resonance and ligand field parameter data, the bonding parameters of these complexes have been calculated. Using Coats–Redfern and Horowitz–Metzger equations, thermodynamic parameters were determined. The spectral data indicate that the dimeric complexes have octahedral geometry around the central metal ions. The cytotoxic activities of all compounds were evaluated towards human breast cancer (MCF‐7) and lung cancer (A549) cell lines. 相似文献
109.
Rabaeh Khalid A. Hammoudeh Issra’ M. E. Moftah Belal Oglat Ammar A. Eyadeh Molham M. Aldweri Feras M. Abdel-Qader Ala’ J. Devic Slobodan 《Journal of Radioanalytical and Nuclear Chemistry》2022,331(2):665-672
Journal of Radioanalytical and Nuclear Chemistry - A novel low toxic normoxic polymer gel dosimeter containing acrylic acid monomer is prepared and characterized for dosimetry in radiotherapy. Gel... 相似文献
110.