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891.
B-doped ZnO and N-doped ZnO powders have been synthesized by mechanochemical method and characterized by TG-DTA, XRD, SEM-EDX, XPS, UV-visible and photoluminescence (PL) spectra. X-ray diffraction data suggests the hexagonal wurtzite structure for modified ZnO crystallites and the incorporation of nonmetal expands the lattice constants of ZnO. The room temperature PL spectra suggest more number of oxygen vacancies exist in nonmetal-doped ZnO than that of undoped zinc oxide. XPS analysis shows the substitution of some of the O atoms of ZnO by nonmetal atoms. Solar photocatalytic activity of B-doped ZnO, N-doped ZnO and undoped ZnO was compared by means of oxidative photocatalytic degradation (PCD) of Bisphenol A (BPA). B-doped ZnO showed better solar PCD efficiency as compare to N-doped ZnO and undoped ZnO. The PCD of BPA follows first order reaction kinetics. The detail mechanism of PCD of Bisphenol A was proposed with the identification of intermediates such as hydroquinone, benzene-1,2,4-triol and 4-(2-hydroxypropan-2-yl) phenol. 相似文献
892.
A fluorimetric method based on fluorescence enhancement effect was developed for the determination of adenosine 5′-monophosphate
(AMP) with 9-anthracene carboxylic acid (9-ANCA)–cetyl trimethyl ammonium bromide (CTAB) system. Fluorescence intensity of
9-ANCA was decreased by the addition of CTAB but addition of AMP again rose the intensity of 9-ANCA gradually. The observed
fluorescence enhancement is attributed to the competitive binding reaction of 9-ANCA and adenosine to CTAB. The enhancement
in the fluorescence intensity was found proportional to the concentration of AMP over the range 2.0 × 10−4 to 1.2 × 10−3 mol dm−3. The ion pair complex is formed spontaneously between 9-ANCA and CTAB. Since the binding interaction is larger for the adenosine–CTAB
pair, the fluorophore 9-ANCA will be released. The quantum yield of free 9-ANCA is higher therefore its fluorescence observed
at 417 nm wavelength is enhanced. This mechanism of competitive molecular interaction is further confirmed by conductometric
measurements. The method was applied successfully for the determination of AMP from pharmaceutical sample. The method is more
selective, sensitive and relatively free from interferences. 相似文献
893.
D. R. Mane D. D. Birajdar Swati Patil Sagar E. Shirsath R. H. Kadam 《Journal of Sol-Gel Science and Technology》2011,58(1):70-79
Cu0.7−
x
Co
x
Zn0.3Fe2O4 (0 ≤ x ≤ 0.5) nanoparticles are prepared by sol–gel auto combustion method, using copper nitrate, zinc nitrate, ferric nitrate,
cobalt nitrate, and citric acid as the starting materials. The process takes only a few minutes to obtain as-received Co-substituted
Cu–Zn ferrite powders. X-ray diffraction (XRD), vibrational sample magnetometer and thermo gravimetric analysis are utilized
in order to study the effect of variation in the Co substitution and its impact on particle size, lattice constant, density,
cation distribution and magnetic properties like magnetization, coercivity, remanent magnetization, ferritization temperature
and associated water content. Lattice parameter found to increase with increasing Co content, whereas X-ray density, bulk
density, particle size showed decreasing trend with the Co content. Cation distribution indicates that the Co and Cu ion show
preference towards octahedral [B] site, Zn occupy tetrahedral (A) site whereas Fe occupy both tetrahedral (A) and octahedral
[B] site. Redistribution of cations takes place for x > 0.3. Saturation magnetization (Ms) increases from 52.99 to 79.62 emu/g (x ≤ 0.3), for x > 0.3 Ms decreases with increase in Co content x. However, coercivity, magnetocrystalline anisotropy and remanent magnetization increases with the Co2+ substitution. 相似文献
894.
Vijay Satam Pravin Patil Balaji Babu Toni Rice Alexander Porte Shannon Alger 《合成通讯》2014,44(7):968-975
Pyrrole- and imidazole-containing polyamides can be tailored to recognize the DNA 6–8 base pair sequence. We found that adding a second amino group via the N1-position of pyrrole or imidazole in polyamides could enhance their DNA binding affinity and water solubility while retaining sequence specificity. Synthesis of the key 1-substituted-4-nitropyrrole (and imidazole)-2-carboxylic acid building blocks are described.
[Supplementary materials are available for this article. Go to the publisher's online edition of Synthetic Communications® for the following free supplemental resource(s): Full experimental and spectral details.] 相似文献
895.
896.
Rahul Patil Umesh Fegade Rajinder Kaur Suban K. Sahoo Narinder Singh 《Supramolecular chemistry》2013,25(7-8):527-532
A new receptor 3-((2-(1H-benzo[d]imidazol-2-yl)phenylimino)methyl)benzene-1,2-diol (1) was synthesised and developed as a highly selective fluorescent chemosensor for the detection of Hg2+ in semi-aqueous media. The fluorescence of receptor 1 was dramatically and selectively quenched on complexation with Hg2+ ion with the detection limit down to 0.20 μM. The developed sensor was successfully applied for the determination of Hg2+ content in water samples. Density Functional Theory (DFT) calculations were performed to study the mechanistic behaviour behind the binding of Hg2+ with receptor 1. 相似文献
897.
In chemical graph theory, several degree-based topological indices are introduced and put forward in the development of quantitative structure-property relationships (QSPR)/quantitative structure-activity relationships (QSAR) studies. However, only a few of them are considered employable in the prediction of physical and chemical properties and biological activities of molecular compounds. Here, we focus our attention on some foremost characteristics of newly defined Geometric–Quadratic and Quadratic–Geometric indices such as prediction power, degeneracy and structure sensitivity. Based on these attributes, we discuss their comparison with other well-established degree-based topological indices with the help of statistical analysis and computational techniques on the data sets of octane, nonane and decane isomers. Some of the graphical approaches, statistical outcomes and computational tests exhibit the dominating nature of the and indices over other topological indices. 相似文献
898.
Siddalingaiah AH Naik SG Patil HD 《Spectrochimica acta. Part A, Molecular and biomolecular spectroscopy》2004,60(11):2499-2503
The solvent effect on the electronic spectra of di(4-bromophenyl)carbazone and its Cu(II), Zn(II), Cd(II) complexes have been studied by synthesizing and characterizing them by magnetic moment, IR, EPR and 1H NMR spectral measurements. The electric dipole moments of these compounds in the first electronically excited state have been determined. The results indicate that the observed band systems in these compounds may be attributed to pi(*) <-- pi transition. 相似文献
899.
Current status on the chemical aspects of nuclear fuel reprocessing is presented with special emphasis on the Purex process which continues to be the process of choice for the last four decades. Better decontamination from fission products, new methods for uraniumplutonium partitioning and removal of actinides from high active waste are challenging areas in process chemistry. The development work on TRUEX and DIAMEX process for treating high active waste is briefly described. An overview of pyrochemical processes, which are important for Integral Fast Reactor Concept, is presented. 相似文献
900.
V. L. Mathe K. K. Patankar R. N. Patil C. D. Lokhande 《Journal of magnetism and magnetic materials》2004,270(3):380-388
Single-phase polycrystalline samples of Bi1−xNdxFeO3 were prepared by standard solid state reaction method. X-ray diffraction (XRD) patterns of the powder samples were recorded and analyzed for the confirmation of crystal structure lattice parameters. Further, these samples were characterized by IR technique to identify and understand the aspect of bonding in the present samples. The dielectric measurements were carried out on the samples as a function of frequency in the range 100 Hz to 1 MHz at room temperature and also as a function of temperature in the range 300–750 K at certain fixed frequencies. The DC and AC electrical resistivity studies were carried out in order to understand conduction mechanism in the samples. 相似文献