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51.
52.
S M Mazhar 《Proceedings Mathematical Sciences》1991,101(2):121-125
This paper deals with the integrability of a power series. Our results generalize certain results of Ram, and Askey and Karlin. 相似文献
53.
Mazhar Iqbal 《Tetrahedron》2004,60(11):2531-2538
The synthesis of racemic Δ12,14-15-deoxy-PG-J1 is readily achieved in six steps employing as the key transformation a one-pot conjugate addition-Peterson olefination sequence using exo-2-trimethylsilyl-3a,4,7,7a-tetrahydro-4,7-methanoinden-1-one. Additionally a Noyori-type three-component coupling approach is employed for the synthesis of enantioenriched epi-Δ12-15-deoxy-PG-J1 from 4(S)-tert-butyldimethylsilyloxycyclopent-2-enone. 相似文献
54.
Tahir AA Hamid M Mazhar M Zeller M Hunter AD Nadeem M Akhtar MJ 《Dalton transactions (Cambridge, England : 2003)》2008,(9):1224-1232
Heterobimetallic molecular precursors [Ti(4)(dmae)(6)(mu-OH)(mu-O)(6)Cu(6)(benzoate)(9)] (1) and [Ti(4)(dmae)(6)(mu-OH)(mu-O)(6)Cu(6)(2-methylbenzoate)(9)] (2) were prepared by the interaction of Ti(dmae)(4) [dmae=N,N-dimethylaminoethanolate] with Cu(benzoate)(2).2H(2)O for (2) and Cu(2-methylbenzoate)(2).2H(2)O for (2), respectively, in dry toluene, for selective deposition of Cu/Ti oxide thin films for possible technological applications. Both the complexes were characterized by melting point, elemental analysis, FT-IR, thermal analysis and single crystal X-ray analysis. Complex (1) crystallizes in the triclinic space group P-1 and complex (2) in the rhombohedral space group R-3. The TGA analysis proves that complexes (1) and (2) undergo facile thermal decomposition at 550 degrees C to form copper titanium mixed metal oxides. The SEM/EDX and XRD analyses suggest the formation of carbonaceous impurity free good quality thin films of crystalline mixtures of beta-Cu(3)TiO(4) and TiO(2) for both (1) and (2), with average grain sizes of 0.29 and 0.74 microm, respectively. Formation of two different homogeneously dispersed oxide phases is also supported by electrical impedance measurements. 相似文献
55.
Mazhar Ul-Islam Taous Khan Waleed Ahmad Khattak Joong Kon Park 《Cellulose (London, England)》2013,20(2):589-596
This study was conducted to develop nanocomposite films of bacterial cellulose (BC) and montmorillonite (MMT) with potent antibacterial activity and potential therapeutic value in wound healing and tissue regeneration. Different composites were prepared through impregnation of BC sheets with 2 and 4 % suspensions of MMT, Na-MMT, Ca-MMT and Cu-MMT. These modified MMTs were prepared through cation exchange strategy. The antibacterial activities of the composites were then assessed against Escherichia coli and Staphylococcus aureus through the disc diffusion assay and colony forming unit (CFU) count methods. BC-Cu-MMT composites prepared with 2 and 4 % MMT displayed clear zones of inhibition against E. coli (20 and 22 mm, respectively) and S. aureus (19 and 20.5 mm, respectively). The untainted BC, BC-MMT, BC-Na-MMT and BC-Ca-MMT did not show clear inhibitory zones against the tested organisms. The reduction in CFU observed following treatment with BC-MMTs (BC-MMT, BC-Na-MMT, BC-Ca-MMT and BC-Cu-MMT) prepared using 2 % MMTs suspension was 7.39, 14.8, 19.2 and 77.9 % for E. coli and 6.8, 13.7, 17.4 and 74.1 %, for S. aureus, respectively. When treated with BC-MMT, BC-Na-MMT, BC-Ca-MMT and BC-Cu-MMT prepared with 4 % MMTs suspension, the reduction in CFU increased to 10.58, 18.37, 24.62 and 85.01 % for E. coli and 9.44, 15.73, 20.40 and 79.79 % for S. aureus, respectively. The outcome of this study will facilitate the development of BC sheets as wound dressings and regeneration materials with antibacterial properties for therapeutic applications without any side effects. 相似文献
56.
The synthesis of enantiopure unsymmetrical N-heterocyclic based zwitterions incorporating imidazolinium and alkylsulfonate or sulfamate groups is described. The desired compounds were prepared in good yields from 1,3-propanesultone or cyclic sulfamidates and imidazolines. The imidazolinium based zwitterions proved to be versatile chiral solvating agents for Mosher’s acid, alcohols, cyanohydrins, amino alcohols, nitro alcohols, thiols, and carboxylic acids with very high shifts in the 1H and 19F NMR. 相似文献
57.
58.
Muhammad Shahid Muhammad Mazhar Mazhar Hamid Paul O' Brien Mohammad A. Malik Madeleine Helliwell 《应用有机金属化学》2010,24(10):714-720
Crystalline copper films were deposited by aerosol‐assisted chemical vapor deposition (AACVD) in the absence of hydrogen from two newly synthesized complexes [Cu(deae)(TFA)]4·1.25THF ( 1 ) and [Cu4(OAc)6(bdmap)2(H2O)2]·4H2O ( 2 ) [deae = N, N‐diethylaminoethanolate, TFA = trifloroacetate, OAc = acetate and bdmap = 1,3‐bis(dimethylamino)‐2‐propanolato]. These precursors were prepared in high yield using mixed ligands and crystallized in tetragonal and triclinic crystal systems with space groups 141/a and P ? 1. Complexes 1 and 2 thermally decomposed at 290 and 250 °C, respectively, to yield copper films which were characterized by SEM/EDX for their morphology and composition and PXRD for their crystallinity and phase. These films have smooth morphologies with particle sizes within the range of 0.3–0.6 µm and may find applications in fabrication of ultralarge‐scale integrated circuits. Copyright © 2010 John Wiley & Sons, Ltd. 相似文献
59.
Effect of surface structure on the catalytic behavior of Ni:Cu/Al and Ni:Cu:K/Al catalysts for methane decomposition 下载免费PDF全文
S. Tajammul Hussain ;Sheraz Gul ;Muhammed Mazhar ;Dalaver H. Anjum ;Faical Larachi 《天然气化学杂志》2008,17(4):374-382
Methane decomposition using nickel, copper, and aluminum (Ni:Cu/Al) and nickel, copper, potassium, and aluminum (Ni:Cu:K/Al) modified nano catalysts has been investigated for carbon fibers, hydrogen and hydrocarbon production. X-ray photoelectron spectroscopy (XPS), static secondary ion mass spectrometry (SSIMS), thermal gravimetric analysis (TGA), Fourier transform infrared (FT-IR), secondary electron microscopy/X-ray energy dispersive (SEM-EDX), and temperature programmed desorption (TPD) were used to depict the chemistry of the catalytic results. These techniques revealed the changes in surface morphology and structure of Ni, Cu, Al, and K, and formation of bimetallic and trimetallic surface cationic sites with different cationic species, which resulted in the production of graphitic form of pure carbon on Ni:Cu/Al catalyst. The addition of K has a marked effect on the product selectivity and reactivity of the catalyst system. K addition restricts the formation of carbon on the surface and increases the production of hydrogen and C2, C3 hydrocarbons during the catalytic reaction whereas no hydrocarbons are produced on the sample without K. This study completely maps the modified surface structure and its relationship with the catalytic behavior of both systems. The process provides a flexible route for the production of carbon fibers and hydrogen on Ni:Cu/Al catalyst and hydrogen along with hydrocarbons on Ni:Cu:K/Al catalyst. The produced carbon fibers are imaged using a transmission electron microscope (TEM) for diameter size and wall structure determination. Hydrogen produced is COx free, which can be used directly in the fuel cell system. The effect of the addition of Cu and its transformation and interaction with Ni and K is responsible for the production of CO/CO2 free hydrogen, thus producing an environmental friendly clean energy. 相似文献
60.
Some new bimetallic carboxylates of tin and germanium with general formula where R1 = m-CH3C6H4, p-CH3C6H4, C6H5, R2 = o-CH3C6H4, p-CH3C6H4, o-CH3OC6H4, C6H5, CH3, have been prepared by the condensation reaction of diethyltin oxide and triarygermyl(substituted)propanoic acid in 1:2 mole ratio, respectively, and characterized by multinuclear (1H, 13C, 119Sn) NMR, 119mSn Mössbauer and IR spectroscopy. The X-ray crystal structure of the ligand I4 [(C6H5)3GeCH(o-CH3OC6H4)CH2COOH] delineate four coordinated germanium atom with a peculiarity of having a molecule of solvent (CHCl3). The chiral center in the synthesized compounds was identified on the basis of 1H NMR data and measurements of angle of rotations. 相似文献