Enzyme immobilization and molecular modeling studies on an organic–inorganic polypyrrole–titanium(<scp>iv</scp>)phosphate nanocomposite
作者:Umair Baig、Mohammed Ashraf Gondal、Md Fazle Alam、Amaj Ahmed Laskar、Mahboob Alam、Hina Younus
DOI:10.1039/c5nj01463h
日期:——
A polypyrrole–titanium(iv)phosphate nanocomposite was synthesized by using facile chemical oxidative polymerization of pyrrole in the presence of titanium(iv)phosphate for YADH immobilization.
Obrubov, V. A.; Shchukin, V. P.; Averbukh, A. Ya., Journal of applied chemistry of the USSR, 1980, vol. 53, p. 197 - 201
作者:Obrubov, V. A.、Shchukin, V. P.、Averbukh, A. Ya.
DOI:——
日期:——
Templated synthesis of mesoporous titanium phosphates for the sequestration of radionuclides
作者:X. Shari Li、Andrea R. Courtney、Wassana Yantasee、Shas V. Mattigod、Glen E. Fryxell
DOI:10.1016/j.inoche.2005.11.014
日期:2006.3
Several mesoporous titanium phosphate phases, with varying pore sizes, were prepared using non-ionic surfactants and easily handled titanium precursors under mild reaction conditions. Preliminary testing reveals that these materials have high affinity for certain radionuclides of environmental concern. (C) 2005 Elsevier B.V. All rights reserved.
Increasing the electrochemical activity of transition metal phosphates in lithium cells by treatment with intimate carbon: The case of titanium phosphate
Amorphous sodium-containing titanium phosphate (sample TiP), obtained by heating a disordered precursor at 300 degrees C under air, electrochemically reacts with lithium by means of non-aqueous lithium cells. Discharge curves of EC/DEC cells in the 3.5-1.5 V region, were different to that observed for NASICON titanium phosphates but the related capacity can be associated to the reduction of Ti4+ to Ti3+. Another sample, C-TiP, obtained by using nitrogen atmosphere during the thermal treatment, was able to provide 75% more capacity in this region. This sample contained carbon because of the incomplete pyrolysis of the surfactant present in the precursor. Carbon is supposed to stay occluded inside the pores considering the values of pores surface area, total conductivity and HRTEM measurements. These titanium phosphates were also tested as negative electrodes. Electrochemical impedance spectroscopy measurements suggest that both titanium phosphates are reduced to yield titanium, lithia and phosphorus at 0.0 V In our opinion, the presence of carbon in C-TiP is the key factor for the enhanced reactivity in the 3.2-1.5 V region but is not enough to obtain a good electrochemical performance, in terms of cycling efficiency. (c) 2006 Elsevier Ltd. All rights reserved.
Methylpyrazine Ammoxidation over Binary Oxide Systems: V. Effect of Phosphorus Additives on the Physicochemical and Catalytic Properties of a Vanadium–Titanium Catalyst in Methylpyrazine Ammoxidation
作者:V. M. Bondareva、T. V. Andrushkevich、O. B. Lapina、D. F. Khabibulin、A. A. Vlasov、L. S. Dovlitova、E. B. Burgina
DOI:10.1023/b:kica.0000016110.21537.0a
日期:2004.1
Oxide vanadium-titanium catalysts modified by phosphorus additives (20V(2)O(5)-(80-n)TiO2-nP(2)O(5), n = 1, 3, 5, 10, and 15 wt %) are studied in methylpyrazine ammoxidation. Two regions of compositions are found corresponding to radically different catalytic properties, namely, catalysts with a low (less than or equal to5 Wt % P2O5) and high (greater than or equal to10 Wt % P2O5) concentration of the additive. In the first case, the introduction of phosphorus is accompanied by a gradual increase in the activity. In the second case, an increase in the additive concentration results in a decrease in the activity and selectivity to the target product, pyrazineamide, and a simultaneous increase in the selectivities to by-products, pyrazine and carbon oxides. The catalysts are characterized by X-ray diffraction analysis, differential dissolution, IR, and NMR spectroscopic data. As in the binary system, the active sites of the samples with a low concentration of phosphorus contain V5+ cations in a strongly distorted octahedral oxygen environment, which are strongly bound to a support due to the formation of V-O-Ti bonds. The catalytic properties of the samples containing greater than or equal to10 wt % P2O5 are due to the presence of the phase of a triple V-P-Ti compound with an atomic ratio V : P : Ti approximately equal to 1 : 1 : 1. The V5+ cations in this compound occur in a weakly distorted tetrahedral oxygen environment and are bound to the tetrahedral P5+ cations.