2,859 publications from this institution
A new class of PANI/Sn(II)SiO3/FCNTs nanocomposite was synthesized by mixing polyaniline into the gel of Sn(II)SiO3 followed by FCNTs (Polyaniline/Sn(II)SiO3/Functionalized Carbon nanotubes). The physico-chemical characterization was carried out by scanning electron microscope, XRD (X-ray Diffraction), FTIR (Fourier Transform Infrared Spectroscopy), ultraviolet–visible spectroscopy, and simultaneous thermogravimetric analysis studies. The ion-exchange capacity (1.2 meq/g) and distribution studies were also determined to understand the ion-exchange capabilities. The DC electrical conductivity studies revile it in the range of 3–5 × 10−3 S/cm. On the basis of distribution studies, ion-selective membrane electrode was designed for Hg(II). The analytical utility of this membrane was established by using it as an indicator electrode in electrometric titrations.
Three carbazole chromophores featuring dicyano, cyano, ethyl acetate and dimethyl acetate groups as an acceptor moiety with a <TEX>${\pi}$</TEX>-conjugated spacer and <TEX>$N$</TEX>-methyl dibenzo[<TEX>$b$</TEX>]pyrole as donor were synthesized by Knovenagel condensation and characterized by IR, <TEX>$^1HNMR$</TEX>, <TEX>$^{13}CNMR$</TEX>, UV-vis, fluorescence spectroscopy, electrochemistry and theoretical B3LYP/6-<TEX>$311G^*$</TEX> level whilst NLO properties and spectroscopic quantities were calculated. Calculations showed remarkable trend with HOMO located on the donor moiety and LUMO on the acceptors dicyano methylene, cyano, ethyl acetate methylene and dimethyl acetate methylene. In agreement with the calculations, solvatochromic, behavior intramolecular charge transfer band was observed in the visible region.
An entry from the Cambridge Structural Database, the world’s repository for small molecule crystal structures. The entry contains experimental data from a crystal diffraction study. The deposited dataset for this entry is freely available from the CCDC and typically includes 3D coordinates, cell parameters, space group, experimental conditions and quality measures.
Tridiminished icosahedron graph is one of nonahedral graphs. In this work, using knowledge of difference equations we drive the explicit formulas for the number of spanning trees in the sequence of some new families of graphs of average degree four based on Tridiminished icosahedron graph by electrically equivalent transformations and rules of weighted generating function. Finally, we compare the entropy of our graphs with other studied graphs with average degree being 4.
Metal-organic frameworks (MOFs) are crystalline porous materials formed from bi- or multipodal organic linkers and transition-metal nodes. Some MOFs have high structural stability, combined with large flexibility in design and post-synthetic modification. MOFs can be photoresponsive through light absorption by the organic linker or the metal oxide nodes. Photoexcitation of the light absorbing units in MOFs often generates a ligand-to-metal charge-separation state that can result in photocatalytic activity. In this Review we discuss the advantages and uniqueness that MOFs offer in photocatalysis. We present the best practices to determine photocatalytic activity in MOFs and for the deposition of co-catalysts. In particular we give examples showing the photocatalytic activity of MOFs in H2 evolution, CO2 reduction, photooxygenation, and photoreduction.
The title compound, (2E)-3-(3,5-dimethyl-1-phenyl-1H-pyrazol-4-yl)-1-(2,5-dimethyl-3-furanyl)prop-2-en-1-one (3) was synthesized in high yield by an aldol condensation between 3-acetyl-2,5-dimethylfuran and 3,5-dimethyl-1-phenylpyrazole-4-carboxaldehyde in ethanolic NaOH at room temperature. Its structure was fully characterized by elemental analysis, IR, 1H NMR, 13C NMR and EI-MS spectral analysis.
The title compound, C(10)H(11)ClN(2)O(2), features an almost planar C(ar)-N(H)-N=C(Cl) unit [torsion angle = 0.8 (1)° whose phenyl substituent is almost coplanar with it [dihedral angle = 2.8 (2)°]; this unit is slightly twisted with respect to the carboxyl -CO(2) fragment [dihedral angle = 10.3 (2)°]. In the crystal, the amino group acts as a hydrogen-bond donor to the carbonyl O atom of an adjacent mol-ecule; the hydrogen bond generates a helical chain that runs along the b axis of the monoclinic unit cell.
The title compound, 2,6-bis(ethyl-9-ethyl-9H-carbazolylmethylene)cyclohexanone has been synthesized by condensation of 9-ethylcarbazole-3-aldehyde and cyclohexanone in ethanol in the presence of pyridine. The structure of this new compound was confirmed by elemental analysis, IR, 1H NMR, 13C NMR and EI-MS spectral analysis.
Three donor acceptor chromophores were synthesized by Knoevenagel condensation. Structures of the chromophoes were conformed by the elemental analysis and EI-MS, FT-IR, 1H-NMR, 13C-NMR spectroscopy. Absorbance and fluorescence spectra of the chromophores were studied in different solvent provide that all the chromophores are good absorbent and emission. All chromophores give same behavior red shift in absorbance and emission spectra as polarity of the solvents increase. Photophysical properties including, oscillator strength, extinction coefficient, transition dipole moment and stokes shift were investigated in order to investigate the physicochemical behaviors of synthesized chromophores. The HOMO energy levels of compound 1, 2 and 3 respectively were calculated front the onset oxidation potential of cyclic voltammogram in acetonitrile.
In the title compound, [Fe(C5H5)(C8H11N4S)], the cyclo-penta-dienyl (Cp) rings of the ferrocene unit are close to being eclipsed. They are inclined to one another at an angle of 1.95 (2)° and lie 3.309 (2)Å away from each other. The ethyl-idene-thio-carbonohydrazide fragment is planar, with an r.m.s. deviation of 0.0347 (2) Å from the mean plane of its eight non-H atoms, and makes dihedral angles of 21.78 (1) and 19.97 (1)° with respect to the two Cp rings. The mol-ecule adopts a trans geometry about the C=N double bond. In the crystal, N-H⋯(N/S) and C-H⋯S inter-actions stack the mol-ecules in an inverse fashion along the b axis.
The synthesis of room-temperature stable ionic liquids was obtained via metathesis reaction, which was accomplished by the reaction 1,10-Phenanthroline monohydrate hydrochloride with lithium-bis(trifluoromethane)sulfonamide in water (shortly, 1,10-PhenanNTf2). The prepared 1,10-PhenanNTf2 was characterized in details with various conventional methods. Finally, it was mixed with conducting binders and deposited on flat-silver electrode (AgE) to result in a sensor that has a fast response to bisphenol A (BPA) in the phosphate buffer phase (PBP). Features include high sensitivity, low-sample volume, reliability, reproducibility, ease of integration, long-term stability, and enhanced electrochemical responses. The calibration plot is linear (r2 = 0.9789) over the 0.1 nM–0.1 mM BPA concentration range. The sensitivity is ∼1.485 μA μM cm−2, and the detection limit is 0.09 ± 0.01 nM (at a signal-to-noise-ratio, SNR of 3). We believe that the developed approach significantly opens up a simple, fast, highly sensitive, and environment-friendly path to fabricate ionic liquid based chemical sensors with broad application prospects.
