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71.
Umar Farooq Rizvi Hamid Latif Siddiqui Saeed Ahmad Matloob Ahmad Masood Parvez 《Acta Crystallographica. Section C, Structural Chemistry》2008,64(10):o547-o549
Molecules of (E)‐3‐(2‐chloro‐6‐methylquinolin‐3‐yl)‐1‐(5‐iodo‐2‐thienyl)prop‐2‐en‐1‐one, C17H11ClINOS, (I), and (E)‐3‐(2‐chloro‐6‐methylquinolin‐3‐yl)‐1‐(5‐methyl‐2‐furyl)prop‐2‐en‐1‐one, C18H14ClNO2, (II), adopt conformations slightly twisted from coplanarity. Both structures are devoid of classical hydrogen bonds. However, nonclassical C—H...O/N interactions [with C...O = 3.146 (5) Å and C...N = 3.487 (3) Å] link the molecules into chains extended along the b axis in (I) and form dimers with an R22(8) motif in (II). The structural analysis of these compounds provides an insight into the correlation between molecular structures and intermolecular interactions in compounds for drug development. 相似文献
72.
Abbasi MA Ahmad VU Zubair M Nawaz SA Lodhi MA Farooq U Choudhary MI 《Natural product research》2005,19(5):509-515
Phytochemical investigation of Symplocos racemosa resulted in the isolation of a new ethyl substituted glycoside, 1-ethyl brachiose-3'-acetate (1) along with four known compounds ketochaulmoogric acid (2), nonaeicosanol (3), triacontyl palmitate (4) and methyl triacontanoate (5). The substitution of ethyl group on 1 was natural because during the course of extraction and purification ethanol was not used. The structural elucidation of the isolated compounds was based primarily on 1D- and 2D-NMR analysis, including COSY, HMQC, and HMBC correlations. The glycoside 1 and triacontyl palmitate (4) displayed the inhibitory potential against lipoxygenase and urease enzyme, respectively. 相似文献
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Abdul Shakoor Tasneem Zahra Rizvi Hafiz Umer Farooq Najmul Hassan Abdul Majid Muhammad Saeed 《Polymer Science Series B》2011,53(9-10):540-545
Polypyrrole was synthesized and doped with dodecylbenzenesulphonic acid; the latter was confirmed by means of FTIR spectroscopy. The percentage of crystallinity of synthesized polymers was estimated from X-rays diffraction studies. The formation of flaky structure in doped polypyrrole was observed by means of SEM. DC conductivity was found to be influenced by dopant dodecylbenzenesulphonic acid. Temperature dependant DC shows three dimensional variable ranges hopping (3D VRH). Activation energy, density of states and hopping length were calculated and found to be influenced by adding dopant to polypyrrole. The doped polypyrrole was found to be more thermally stable as compared to that of pristine polypyrrole. 相似文献
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Kaleem Ahmad Walid Tawfik Wazirzada A. Farooq Jagdish P. Singh 《Applied Physics A: Materials Science & Processing》2014,117(3):1315-1322
In this work, alumina (Al2O3) containing different volume % of titanium carbide (TiC) ranging from 0 to 30 were consolidated by the novel spark plasma sintering. The spectroscopic analysis of the plasma generated by irradiation of laser Nd:YAG (λ = 1,064 nm) on different concentrations of the composites in air atmospheric pressure was performed. The qualitative examination of the composites confirms the presence of aluminum, titanium, and carbon as major elements, while magnesium and sodium have been found as minor trace elements. Plasma parameters were estimated by assuming the LTE conditions for optically thin plasma. The electron density and temperature were evaluated by using the Stark broadening and intensity of selected aluminum emission lines, respectively. The addition of TiC to Al2O3 shows a linear behavior with plasma temperature corroborated by the calibration curve of Ti in the composites. The results suggest that calibration curve between plasma temperature and the composites can be used to estimate different concentrations of TiC in Al2O3 without analyzing the whole elements in the composites and thus opens up new applications of LIBS in ceramic industry. 相似文献
80.
W. Aslam Farooq M. Atif Syed Mansoor Ali Amanullah Fatehmulla M. Aslam 《Optics and Spectroscopy》2014,117(3):386-391
TiO2 thin film has been widely used as photoelectrode in dye-sensitized solar cells. It can also be used in quantum dot synthesized solar cells. Study of its effects in different spectrum of light is important for its use in solar cells. We have reported effects of 1064 nm laser on the surface morphology, structural and optical properties of nanostructured TiO2 thin film deposited on glass substrates using sol-gel spin coating technique. Q-Switched Nd:YAG pulsed laser at various power densities is used in this study. Surface morphology of the film is investigated using X-ray diffraction (XRD) and atomic force microscopy technique. The XRD pattern of as deposited TiO2 thin film is amorphous and after laser exposure it became TiO2 anatase structure. Atomic force microscopy of the crystalline TiO2 thin film shows that the grain size increases by increasing laser power density. The calculations of the band gap are carried out from UV/Visible spectroscopy measurements with JASCO spectrometer. For laser power density of 25 MW/cm2 there is an increase in the transmission and it decreases at the value of 38 MW/cm2 and band gap decreases with increasing laser power density. Photoluminescence spectra of the crystalline TiO2 thin film indicate two broad peaks in the range of 415 and 463 nm, one for band gap peak (415 nm) and other for oxygen defect during film deposition process. 相似文献