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排序方式: 共有336条查询结果,搜索用时 171 毫秒
331.
Ayaz Mohd Aftab Aslam Parwaz Khan Shaista Bano 《Journal of Dispersion Science and Technology》2013,34(10):1465-1469
The interaction of clofazimine (CFZ) with divalent metal cations was studied by measuring fluorescence quenching spectra, synchronous fluorescence spectra and ultraviolet spectra. The fluorescence quenching spectra of CFZ in the presence of metal ions showed that metal ions quenched the fluorescence of CFZ. The quenching constants were determined using the Stern–Volmer equation. The binding constants (log K) and binding site were obtained. The thermodynamic parameters obtained in this study revealed that the interaction between CFZ and metal ions was mainly driven by a hydrophobic force. The conformational changes of CFZ were investigated by synchronous spectrum studies. 相似文献
332.
Aslam B. Tamboli Rajesh G. Bhorkade Basavraj S. Kalshetti Shivaji D. Ghodake 《高分子科学杂志,A辑:纯化学与应用化学》2013,50(11):983-993
AbstractA new series of soluble aromatic polyamides was synthesized by low temperature solution polycondensation of novel aromatic diamine namely 3,5-bis-(4′-amino phenyl)-4-(4″-methoxy-2″-pentadecyl phenyl) 1,2,4-triazole (VII) with aromatic diacid chlorides, viz. isophthaloyl chloride (IPC) and terephthaloyl chloride (TPC). The aromaticdiamine (VII) was characterized by elemental analysis, FT-IR, NMR (1H, 13C), and mass spectrometry. Copolyamides were also synthesized by employing various mole proportions of IPC and TPC with diamine (VII). Inherent viscosities of these polyamides were in the range of 0.50–0.65 dL/g in DMAc, indicating formation of moderate to high molecular weight of polyamides. These polyamides showed good solubility in polar aprotic solvents such as N,N-Dimethyl acetamide (DMAc), N-Methyl 2-pyrrolidone (NMP), N, N, Dimethyl formamide (DMF), and Dimethyl sulphoxide (DMSO), which may be due to incorporation of pendant methoxyphenyl moiety with pentadecyl units. The amorphous morphology of polyamides as evidenced by XRD. These polyamides had lower glass transition temperatures; as determined by DSC, compared to the Tg of conventional aromatic polyamides due to internal plasticization effect of long alkyl pentadecyl group. Polymers showed good thermal stability, with initial decomposition temperature above 300?°C. 相似文献
333.
Adhem Mohamed Aslam Seenivasan Rajagopal Mariappanadar Vairamani Maddula Ravikumar 《Transition Metal Chemistry》2011,36(7):751-759
Abstract
Iron(III)–salen complexes catalyze the H2O2 oxidation of various ring-substituted anilines in MeCN have been studied, and [O=FeIV(salen)]+· is proposed as the active species. Study of the kinetics of the reaction by spectrophotometry shows the emergence of a new peak at 445 nm in the spectrum which corresponds to azobenzene. Further oxidation of azobenzene by H2O2 leads to the formation of azoxybenzene. ESI–MS studies also support the formation of these products. The rate constants for the oxidation of meta- and para-substituted anilines were determined from the rate of decay of oxidant as well as the rate of formation of azobenzene, and the reaction follows Michaelis–Menten kinetics. The rate data show a linear relationship with the Hammett σ constants and yield a ρ value of −1.1 to −2.4 for substituent variation in the anilines. A reaction mechanism involving electron transfer from aniline to [O=Fe(salen)]+· is proposed. The presence of axial ligands modulates the activity of the complex. 相似文献334.
Aiza Azam Gulzar Muhammad Muhammad Shahbaz Aslam Muhammad Mudassir Iqbal Muhammad Arshad Raza Naeem Akhtar Muhammad Ajaz Hussain Noreen Sajjad Asad Syed Ali H. Bahkali Zahid Shafiq 《应用有机金属化学》2023,37(1):e6923
The multifunctional zinc oxide nanoparticles are synthesized using a cost-effective, efficient, eco-friendly, simple, and clean synthesis approach. Herein, we reported the antibacterial and wound healing potential of zinc oxide nanoparticles (ZnO-NPs) prepared using psyllium gel (PG) as the reducing and stabilizing agent. The PG-mediated zinc oxide nanoparticles (PG-ZnO-NPs) were characterized using UV–Vis, photoluminescence (PL), FTIR, XRD, Raman, and SEM. UV–Vis spectral studies confirmed the surface plasmonic resonance (SPR) band at 364 nm. PL results demonstrated the fluorescent or emission nature of PG-ZnO-NPs. FTIR analysis confirmed characteristic peaks at 873.82 and 619.88 cm−1 due to the tetrahedral coordination of zinc and the formation of the Zn-O bond. XRD and Raman confirm the formation of PG-ZnO-NPs, whereas SEM analysis revealed PG-ZnO-NPs are rod-shaped, having hexagonal prism-like bases, and EDX exhibited the elemental composition of PG-ZnO-NPs. The as-synthesized PG-ZnO-NPs possessed prominent microbicidal potential against gram-positive (Bacillus subtilis and Bacillus licheniformis) and gram-negative (Escherichia coli and Salmonella shigella) bacterial strains in terms of zone of inhibition (ZOI), minimum inhibitory concentration (MIC), and minimum bactericidal concentration (MBC). In vivo biological investigations with mice show that the synthesized PG-ZnO-NPs possess outstanding biocompatibility and wound healing potential. PG-ZnO-NPs dressing significantly speeds up full-thickness wound repair by triggering a decrease in MMP-1 and MMP-2 and escalating the mRNA levels of collagen types (I & III) and fibronectin. Thus, our work validates that the inclusion of PG-ZnO-NPs in dressing shows excellent potential for acute wound management. 相似文献
335.
Optical Review - The effects of guided mode resonance (GMR) are largely used in optical communications because of its accurate line width and good capability. Specially study of titanium dioxide... 相似文献
336.
Thin-film diamond temperature sensor arrays used in harsh aerospace environments were investigated using micro-Raman spectroscopy. Raman spectra of three of the samples obtained under specific experimental conditions are presented. On annealing a sample, an increase in graphite content and restoration of long-range order in its lattice are suggested. Additionally, an untreated sample on irradiation with 1064 nm radiation from a low-power continuous-wave Nd: YAG laser exhibits an increase in graphite content. Similar irradiation of an annealed sample shows an increase in the graphite content, a decrease in diamond-like carbon content and the appearance of a band at 1607 cm−1. 相似文献