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101.
Journal of Solid State Electrochemistry - A non-enzymatic sensor was developed for simultaneous detection of glucose, ethanol, and glycerol concentrations in wine using nickel nanoparticles on...  相似文献   
102.
Natural hydroxyapatite‐supported MnO2 (MnO2@NHAp) was easily prepared in situ from reduction of potassium permanganate with natural hydroxyapatite derived from cow bones in water at room temperature, and its structure was characterized using flame atomic absorption spectroscopy, X‐ray diffraction, thermogravimetric analysis, scanning electron microscopy and energy dispersive spectroscopy. The catalytic activity of the synthesized catalyst was investigated for the aerobic oxidation of alkylarenes and alcohols. MnO2@NHAp shows excellent catalytic performance for the oxidation of alkylarenes and alcohols to their corresponding carbonyl compounds without using any other oxidizing agent. This catalyst can be readily recycled and reused for several runs without any significant loss of efficiency. Copyright © 2016 John Wiley & Sons, Ltd.  相似文献   
103.
Journal of Inclusion Phenomena and Macrocyclic Chemistry - Beta-carotene (BC) is a vitamin A precursor and has potential anticancer benefits, but the delivery of BC is hindered by its low...  相似文献   
104.
Nonlinear Dynamics - This paper focuses on finding soliton solutions for an intrinsic fractional discrete nonlinear electrical transmission lattice. Our investigation is based on the fact that for...  相似文献   
105.
Nanomagnetic bisethylferrocene‐containing ionic liquid supported on silica‐coated iron oxide (Fe3O4@SiO2@Im‐bisethylFc [HC2O4]) as a novel catalyst was designed and synthesized. The described catalyst was recycled and used without change in the time and efficiency of the condensation reaction. The Fourier transform‐infrared spectroscopy (FT‐IR), scanning electron microscopy images, X‐ray diffraction patterns, energy‐dispersive X‐ray spectroscopy, transmission electron microscope and vibrating‐sample magnetometer results confirmed the formation of Fe3O4@SiO2@Im‐bisethylFc [HC2O4] magnetic nanoparticle. The novel bis‐coumarin derivatives were identified by 1H‐NMR, 13C‐NMR, FT‐IR and CHNS analysis.  相似文献   
106.
The present study describes the synthesis and characterization of titania-silica mixed imidazolium based ionic liquid (Ti-Si-IL) as well as evaluation of its adsorption behavior towards the 2,4-dinitrophenol (2,4-DNP) and 2,4,6-trichlorophenol (2,4,6-TCP). Synthesized Ti-Si-IL adsorbent was characterized by Fourier transform infrared spectroscopy (FT-IR), field emission scanning electron microscopy (FESEM), BET surface area Brunauer-Emmett-Teller (BET), thermogravimetric analysis (TGA) and elemental analysis (CHN). The adsorption of 2,4-DNP and 2,4,6-TCP on Ti-Si-IL was investigated systematically by evaluating the effects of adsorbent dosage, initial pH, contact time and temperature. Satisfactory adsorption 95% and 65% for 2,4-DNP and 2,4,6-TCP was observed at pH 4 and 6, respectively. The kinetic results for 2,4-DNP and 2,4,6-TCP on Ti-Si-IL indicated that the kinetic data follows pseudo-second-order model (R2 = 0.9985 and 0.9750, respectively). Adsorption isotherms were fitted well by the Langmuir model for 2,4-DNP (qm = 44.64 mg g?1 at 318 K) and Freundlich model for 2,4,6-TCP (KF = 0.63 mg g?1 at 318 K). The +ΔH° and -ΔG° values demonstrated that the adsorption of 2,4-DNP was endothermic and spontaneous in nature. While the -ΔH° and +ΔG° values for 2,4,6-TCP adsorption demonstrated exothermic and comparatively nonspontaneous. During the removal process, the role of different functional groups, cyclic structure was monitored and found that the ionic property as well as π-π interactions of host molecules played important role in the extent of adsorption.  相似文献   
107.
The novel title compounds, (pipzH2)1.5(pydcH)3·3.7H2O, 1, (pipzH2)[Zr(pydc)3]·8H2O, 2 and (pipzH2)[Ce(pydc)3]·8H2O, 3 in which pydcH2 is pyridine-2,6-dicarboxylic acid and pipz is piperazine were obtained in aqueous solution. The compounds were characterized by IR, 1H NMR and 13C NMR spectroscopy, elemental analyses, and X-ray crystallography. Compound 1 is resulted from proton transfer between pydcH2 and pipz. However, compounds 2 and 3 are resulted from complexation of 1 and corresponding metallic salts. Both compounds 2 and 3 contain three pyridine-2,6-dicarboxylate species as tridentate ligands, one piperazinediium as counter ion, and eight-uncoordinated water molecules in the asymmetric unit. In both structures each M(IV) is coordinated in a distorted tricapped trigonal prism geometry by three nitrogen and six oxygen atoms of carboxylate groups of three (pydc)2− fragments. In the crystal structures of 1, 2 and 3, extensive O–H···O, N–H···O and C–H···O hydrogen bonds as well as electrostatic forces, C–H···π, C–O···π and π–π stacking play important roles in stabilizing structures. The geometrical parameters of the [M(pydc)3]2− anionic complexes, where M = Ce(IV), Zr(IV) have been optimized with the B3LYP method of density functional theory (DFT) and ab initio Hartree–Fock (HF) methods for comparison. In addition, we have studied the structures of (pydc)2− anion and its mono and doubly protonated forms, (pydcH) and pydcH2. The electronic properties of the anionic complexes and ligands have been investigated based on the natural bond orbital (NBO) analysis at the B3LYP method which verifies that the synergistic effect has been occurred in the title complexes. In solution study of 2, the stoichiometry and stability constant of complexation of pipz, pydc, pydc–pipz proton transfer system and Zr(IV) ion in aqueous solution were investigated by potentiometric method.  相似文献   
108.
A series of phosphine-sulfonate ligands bearing 2-, 3-and 4-vinylphenyl on the phosphorus atom were designed, synthesized,characterized and investigated in Ni-and Pd-catalyzed ethylene polymerization. The structure of the phosphine-sulfonate Pd complex bearing2-vinylphenyl on the phosphorus atom showed 2,1-insertion for the 2-vinyl group. The phosphine-sulfonate Ni complex bearing 2-vinylphenyl resulted in significantly increased thermal stability and polyethylene molecular weights(Mn=3.69×104 g·mol-1 at 80 °C) versus the counterparts bearing 3-/4-vinyl groups as well as previously reported phosphine-sulfonate Ni complexes bearing bulky biaryl substituents.  相似文献   
109.
Journal of the Iranian Chemical Society - Face-centered cubic structure of nickel oxide (NiO) nanoparticles with 30 nm average size was synthesized by co-precipitation method with some...  相似文献   
110.
An efficient synthesis of 2,4,6-triarylpyridines is described which involves heating a mixture of an acetophenone oxime and an epoxy styrene under neutral, solvent-free conditions. Kröhnke pyridine products are obtained in excellent yields.  相似文献   
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