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11.
Zhigang Yin Nuofu Chen Shulin Song Jun Zhong Kurash Ibrahim 《Solid State Communications》2005,135(7):430-433
Nickel-doped ZnO (Zn1−xNixO) have been produced using rf magnetron sputtering. X-ray diffraction measurements revealed that nickel atoms were successfully incorporated into ZnO host matrix without forming any detectable secondary phase. Ni 2p core-level photoemission spectroscopy confirmed this result and suggested Ni has a chemical valence of 2+. According to the magnetization measurements, no ferromagnetic but paramagnetic behavior was found for Zn0.86Ni0.14O. We studied the electronic structure of Zn0.86Ni0.14O by valence-band photoemission spectroscopy. The spectra demonstrate a structure at ∼2 eV below the Fermi energy EF, which is of Ni 3d origin. No emission was found at EF, suggesting the insulating nature of the film. 相似文献
12.
Sulaiman Wadi Harun Nizam Tamchek Mohd Kamil Abd-Rahman Prabakaran Poopalan Harith Ahmad 《Optical Review》2003,10(3):133-135
A multiwavelength Brillouin/erbium fibre laser (BEFL) which operates in the long wavelength (L-band) region is demonstrated for potential applications in an L-band wavelength division multiplexing (WDM) communication system. The laser configuration consists of a long erbium-doped fibre to enable L-band amplification where two 3-dB couplers take a portion of the generated BEFL signal and re-inject it into the single mode fibre to seed a cascaded BEFL line in the same direction as the first BEFL line. A stable and strong laser comb of up to five lines with 10-GHz spacing has been obtained with a Brillouin pump (BP) of 9.2 mW and a 980 nm pump of 92 mW. The BEFL has shown a broad tuning range with a tuning characteristic for line #1 which is flat over a range greater than 9.9 nm. 相似文献
13.
S. Franchoo F. Ibrahim F. Le Blanc M. Lebois A. Olivier C. Phan Viet B. Roussière R. Sifi D. Verney 《Hyperfine Interactions》2006,171(1-3):117-119
The availability of both a tandem deuteron beam and a linac electron beam, the latter converted into Bremsstrahlung, at the
new ALTO facility at IPN-Orsay offers a unique opportunity to compare the performance of a laser ion guide under different
regimes. The ALTO accelerator has delivered its first electron beam at the end of 2005 and a design for a gas-cell prototype
is being studied. 相似文献
14.
Anwar Usman Ibrahim Abdul Razak Hoong‐Kun Fun Suchada Chantrapromma Yan Zhang Jian‐Hua Xu 《Acta Crystallographica. Section C, Structural Chemistry》2002,58(5):o287-o288
In the title compound, C18H13BrClNO3, the heterocyclic ring of the indole is distorted from planarity towards an envelope conformation. The orientations of the indole, oxetane, chloro and bromophenyl substituents are conditioned by the sp3 states of the spiro‐junction and the Cl‐attached C atoms. 相似文献
15.
Unusual Formation and Structure of a O‐Sulfinato Zinc Complex Whereas the reaction between hydrotris[(N‐xylyl)‐thioimidazolyl]borato‐zinc perchlorate ([ L· Zn‐OClO3]) and ethanethiolate under an inert atmosphere leads to the thiolate complex [ L· Zn‐SC2H5], the same reaction in air produces the sulfinato complex [ L· Zn‐O‐S(O)‐C2H5] ( 1 ). 1 is the first fully characterized sulfinato‐zinc complex. Its structure determination has confirmed the unusual coordination of the sulfinato ligand via one of its oxygen atoms. 相似文献
16.
Gas-phase thermolysis of thieno[3,2-e][1,2,4]triazines gave benzonitrile, isothiazole, pyrimidine, [1]benzothieno[2,3-d]pyrimidine and thieno[3,2-d]thiazole derivatives. A mechanism of these pyrolytic transformation was proposed. Two new and efficient syntheses of the starting thieno[3,2-e][1,2,4]triazines were reported. 相似文献
17.
18.
Rodolphe Clérac Dieter Fenske Ibrahim Issac Alexander Rothenberger 《Journal of Cluster Science》2004,15(2):189-198
Two Fe–Ta containing sulfido complexes were prepared by the reaction of the metal halide salts with bis-trimethylsilylsulfide in the presence of PMe3. The complexes demonstrate that coordination chemistry with iron sulfides can give access to a range of heterometallic complexes. In [Cl(Me3P)Ta(
2-S)2(
3-S)Fe(PMe3)2]2 the two [Cl(Me3P)Ta] units are arranged around one central Fe2(
2-S)2 unit. In [(Me3P)4(MeCN)2FeII]2+[(Me3P)2TaIVFeII
3(
3-S)4Br4]2– a [TaFe3S4]2+ cuboidal arrangement was observed. The complex salt forms a polymeric structure in the solid-state with weak H-bonds between the ions. The [(Me3P)2TaIVFeII
3(
3-S)4Br4]2– ion was characterised by magnetic measurements showing strong antiferromagnetic interactions between the metal centres. 相似文献
19.
The preparation and characterization of MnII, FeIII and CuII complexes of three tridentate pyridyl hydrazones are reported.
The ligands were prepared via Schiff base condensation of 6-chloro-2-hydrazopyridine with alpha-formyl-(L1), alpha-acetyl-(L2),
or alpha-benzoyl-(L3) pyridine. The structural characterization of the compounds prepared was based on elemental analyses,
electrical conductance and magnetic moment measurements, 1H-n.m.r., i.r., u.v.-vis. and e.s.r spectroscopic methods. The overall
structure and reactivity of the metal chelates critically depend on the ligand substituents within the carbonyl moiety. Octahedral
and tetrahedral monomeric species were proposed for MnII complexes, and an octahedral environment for the FeIII complexes.
Regarding the copper(II) complexes, a monomeric square-planar and a dimeric structure with a chloride bridge in square-pyramidal
geometry were suggested. In the presence of molecular oxygen, MnII and CuII complexes catalyse the oxidative transformation
of catechol (benzene-1,2-diol) to the corresponding o-benzoquinone. Iron(III) complexes catalyse the aerobic oxidation of
catechol to the intradiol cleavage product. The catalytic activity has been correlated with the Lewis acidity of the metal
centres created according to the nature of the ligand substituents. The probable mechanistic implications of the catalysed
oxidation reactions are discussed.
This revised version was published online in June 2006 with corrections to the Cover Date. 相似文献
20.
Dimethyl and diethyl fluoromalonates were prepared from hexafluoropropene by its exhaustive alcoholysis or alternatively its ammonolysis and alcoholysis. Fluoromalonates thus obtained or their alkylated derivatives were condensed with o-phenylenediamine or its substituted derivatives to give a number of 1H-3-fluoro-1,5-dibenzodiazepin-2,4(3H,5H)-diones. 相似文献