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81.
Summary Ternary 1:1:1 complexes of YIII, CoII, NiII, CuII, LaIII, CeIII and UO 2 2+ with N-(2-acetamido)iminodiacetic acid (H2ADA) as primary ligand and salicylic, anthranilic or phthalic acid as secondary ligand are described. The complexes of CoII and CuII were isolated and characterized by microanalysis, molar conductance measurements, thermal analysis, i.r. and u.v.-vis. spectra. The formation constants of the 111 ternary complexes were determined potentiometrically in 20% (w/w) EtOH-H2O at 24 °C. The stabilities of the 111 M n+ :ADA2–:aromatic acid ternary complexes are higher than those of the corresponding 11 M n+ :aromatic acid binary complexes.  相似文献   
82.
In-situ NMR studies on the reactions of Pt{CH2 = CHSi(Me)2}2O)(PCy3) with phosphines, HSiEt3 and--hydrogen or Pt(L)(L')(Me)(2) alone enable the detection of cis-Pt(L)(L')(H)2 [L = PCy3 and L' = PCy2H, PPh3 or PCy3] which then undergo hydride site interchange and H2 reductive elimination on the NMR timescale.  相似文献   
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A N-heterocyclic carbene–copper complex grafted on graphene oxide with an ionic liquid framework was prepared. The synthesis of (i) 1,2,3-triazole derivatives by ‘Click reaction’ and (ii) propargylamine derivatives by ‘A3 coupling reaction’ in aqueous media by this new catalyst were all successfully accomplished. The catalyst is characterized using infrared spectroscopy, Raman spectroscopy, scanning electron microscopy, thermogravimetric analysis and energy dispersive X-ray spectroscopy, X-ray photoelectron spectroscopy, transmission electron microscopy, and elemental analysis. The catalyst is reused in the ten reaction cycles without considerable loss of catalytic activity.

Graphical abstract

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86.
Polyesters consisting of substituted aromatic type Schiff base mesogenic unit andpolymethylene spacers were synthesized and their thermal transitions and liquid crystallineproperties were studied. The liquid crystalline behaviour has been characterized by differentialscanning calorimetry (DSC) and optical polarizing microscopy. Structural broadening bysubstitution of methoxy group in 2, 2" positions of the mesogenic core produce polymers withlower transition temperatures. Polymers synthesized from ortho and meta substituted phenylenediamine did not form a liquid crystal phase.  相似文献   
87.
In this study we investigated the electrocatalytic oxidation of anti‐inflammatory drug (paracetamol) on Nickel and Nickel–copper alloy modified glassy carbon electrodes (GC/Ni and GC/NiCu) in alkaline solution. These electrodes prepared by galvanostatic method and different electrochemical techniques such as cyclic voltammetry and chronoamperometry were used to track the oxidation process and its kinetics. From Voltammetric studies we concluded that in the presence of drugs the anodic peak current of low valences Nickel species increased, followed by a decrease in the corresponding cathodic current peak. This indicates that drugs were oxidized on the redox mediator which was immobilized on the electrode surface via an electrocatalytic mechanism. Using Laviron's equation, the values of α and ks for the immobilized redox species were determined. The anodic peak currents show linear dependency with the square root of scan rate. This behavior is the characteristic of a diffusion controlled process. Under the CA regime the reaction followed a Cottrellian behavior and the diffusion coefficient of paracetamol was found in agreement with the values obtained from CV measurements.  相似文献   
88.
Structural Chemistry - The detection methods used to analyze abused drugs should be sensitive sufficiently. Here in, we propose carbon nanotube (CNT) functionalized with COOH and CONHCH3 groups as...  相似文献   
89.
Immobilization of copper(I) ions on magnetic nanoparticles was performed using surface modification of Fe3O4 with creatine. Fe3O4@creatine-Cu(I) magnetic catalyst was synthesized and applied in C&bond;X cross-coupling reactions with aryl halides in a deep eutectic as a green solvent. The results indicate the Fe3O4@creatine-Cu(I) magnetic nanoparticles showed excellent activity and high stability. In addition, it was revealed that this catalyst can be recycled five times without significant loss in catalytic activity.  相似文献   
90.
Single phase LiCr0.2Ni0.4Mn1.4O4 spinel has been synthesized by a simple sucrose assisted combustion method that yields highly crystalline homogeneous sub-micrometric samples (650 nm). The LiCr0.2Ni0.4Mn1.4O4, with capacity retention of 92% at 60 C discharge rate, shows the highest rate capability among LiNi0.5Mn1.5O4-type cathodes. It delivers very high-power (34.8 kW kg?1 at 60 C). Studies developed at 55 °C demonstrate that LiCr0.2Ni0.4Mn1.4O4 retains huge rate capability and large cycleability at high temperature.  相似文献   
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