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94.
Noor-ul H. Khan Santosh Agrawal Sayed H.R. Abdi Eringathodi Suresh 《Tetrahedron letters》2008,49(4):640-644
The synthesis of α-aminonitriles of ketones and aldehydes was performed in very short reaction times (20 min) with excellent yields in the presence of 5 mol % of Fe(Cp)2PF6 under solvent-free conditions. 相似文献
95.
Moutusi Dasgupta Haregewine Tadesse Alexander J. Blake Samaresh Bhattacharya 《Journal of organometallic chemistry》2008,693(20):3281-3288
Reaction of N-(4-R-phenyl)picolinamide (R = OCH3, CH3, H, Cl and NO2) with [Ir(PPh3)3Cl] in refluxing ethanol in the presence of a base (NEt3) affords two yellow complexes (1-R and 2-R). The 1-R complexes contain an amide ligand coordinated to the metal center as a monoanionic bidentate N,N donor along with two triphenylphosphines, a chloride and a hydride. The 2-R complexes contain an amide ligand coordinated to the metal center as a monoanionic bidentate N,N donor along with two triphenylphosphines and two hydrides. Similar reaction of N-(naphthyl)picolinamide with [Ir(PPh3)3Cl] affords two organometallic complexes, 3 and 4. In complex 3 the amide ligand is coordinated to the metal center, via C–H activation of the naphthyl ring at the 8-position, as a dianionic tridentate N,N,C donor, along with two triphenylphosphines and one chloride. Complex 4 is similar to complex 3, except a hydride is bonded to iridium instead of the chloride. Structures of the 1-OCH3, 2-Cl and 4 complexes have been determined by X-ray crystallography. All the complexes are diamagnetic, and show characteristic 1H NMR signals and intense MLCT transitions in the visible region. Cyclic voltammetry on all the complexes shows a IrIII–IrIV oxidation within 0.50–1.16 V vs. SCE and a reduction of the coordinated amide ligand within −1.02 to −1.25 V vs. SCE. 相似文献
96.
Fateme Abdi 《哲学杂志》2016,96(13):1305-1317
Thick (3.0 mm) Al samples (7049 an alloy with 15 elements) were implanted by N+ ions of 30 keV energy and fluence of 5 × 10 17 N+ cm?2 at different temperatures. The surface modification of the samples was studied using X-ray diffraction (XRD) and atomic force microscope (AFM) analysis. XRD spectra of the samples clearly showed the formation of different phases of AlN. Crystallite sizes (coherently diffracting domains) obtained from AlN diffraction lines showed that at a certain substrate temperature the crystallite size decreases considerably. AFM images showed the formation of grains on Al samples, and it was observed that both grain size and sample surface roughness first decrease and then increase with temperature (i.e. a minimum at a certain temperature is observed). In addition at this temperature, a minimum of intensity is also observed for the intensity of different phases of AlN and the intensity ratio of AlN (200)/AlN (311). This phenomenon is similar to those obtained for thin films and pure metal foils though the sample studied in this work is an Al alloy and the minimum for Al occurred at a value three times larger than that reported for the above cases. Alloy nature of this sample with 14 elements is responsible for the observed results because they may act as defects. Results may also be affected by the residual gases, substrate temperature, dissociation of water in the chamber and the ion energy. Results also showed that the processes of Al nitride and Al oxide formations are competing with each other; decrease of aluminium nitride phases are associated with increase of aluminium oxide phases. 相似文献
97.
In this paper, conformal Kenmotsu manifolds are introduced. We consider CR-hypersurfaces of a conformal Kenmotsu manifold whose shape operator is parallel, scalar, recurrent or Lie \( \xi \)-parallel. It is proved that if the Lee vector field of a conformal Kenmotsu manifold is tangent and normal to these type of CR-hypersurfaces then the CR-hypersurfaces are totally geodesic and totally umbilic, respectively. An example of a three-dimensional conformal Kenmotsu manifold is constructed for illustration that is not Kenmotsu. 相似文献
98.
The synthesis of some fluorescent 2,6‐dicyano‐3,5‐disubstituted anilines using cellulose sulfuric acid (Cellulose‐SA) as an environmentally benign catalyst in H2O is described. The one‐pot reaction of 1,3‐diketone and three equiv. of malononitrile was carried out in the presence of one equiv. of a secondary amine, Cellulose‐SA as catalyst, and H2O as solvent. The photophysical properties (λAbs., λFlu.) of the synthesized compounds in CH2Cl2, MeCN, and MeOH have been measured. The emission spectra of the new compounds in the solid state are also reported. 相似文献
99.
Abdi Hamid Ait Messaoudene Noureddine Kolsi Lioua Naceur Mohamed Wahib 《Journal of Thermal Analysis and Calorimetry》2021,144(5):1749-1759
Journal of Thermal Analysis and Calorimetry - The present study aims at estimating the values of an electrochemical model parameter of a proton exchange membrane fuel cell (PEMFC). A variant of the... 相似文献
100.
The synthesis of 6,6- and 5,6-bicyclic pyridone scaffolds has been completed using (i) an intramolecular Mitsunobu reaction and/or (ii) hydrolysis of a bicyclic pyridinium salt intermediate. Regioselective functionalization of the pyridone ring has been achieved via either direct lithiation or use of the "halogen dance" reaction. Suzuki coupling then allows introduction of aryl units at C(7)/C(9) or C(8) onto the bicyclic pyridone scaffold at either an early or late stage in the synthetic sequence. Suzuki couplings involving iodopyridinium intermediates are particularly effective. 相似文献