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Through the sol–gel process, using the so-called neutral amine route, spherical particles of 1:1 zirconia–titania were synthesized from zirconium(IV) and titanium(IV) butoxides as well as 1,12-diaminododecane as precursor species. The obtained product exhibited a hexagonal structure, as determinated by X-ray diffraction data. The obtained material was also characterized by thermogravimetry, differential scanning calorimetry, infrared spectroscopy, scanning electron microscopy, and surface area measurements. Despite the release of template molecules on heating, the spherical morphology was retained up to about 1200°C, at which the disruption of the spheres took place. 相似文献
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de Farias RF de Souza JM de Melo JV Airoldi C 《Journal of colloid and interface science》1999,212(1):123-129
The effects exhibited by adsorbed conducting polyaniline on the redox process on a molybdenum oxide surface were studied. Thermogravimetric results indicate a 4% polyaniline deposition. Cyclic voltammograms of the adsorbed polymer on MoO3 show that polyaniline exerts remarkable effects on the molybdenum blue oxidation-reduction process, with oxidation and reduction potentials of 0.33 and 0.18 V, respectively. This effect strongly enhances the electrode response, and can be used as an important tool in qualitative and/or quantitative determinations of molybdenum in solution as well as in any substrate. Copyright 1999 Academic Press. 相似文献
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Rafael F. Barostichi Paulo D. Cordaro Gerson Petronilho 《Mathematische Nachrichten》2013,286(14-15):1439-1451
In this work we study the Borel property for smooth solutions to systems of complex vector fields associated to locally integrable structures. Inspired by the recent article [6], in which the Borel property was studied for generic submanifolds of the complex space, we prove similar results in this more general set up. In particular we obtain, for the case of corank one structures, a necessary and sufficient condition for the validity of the Borel property. 相似文献
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Rafael F. Barostichi 《Journal of Mathematical Analysis and Applications》2011,382(1):248-260
Given a Gs-involutive structure, (M,V), a Gevrey submanifold X⊂M which is maximally real and a Gevrey function u0 on X we construct a Gevrey function u which extends u0 and is a Gevrey approximate solution for V. We then use our construction to study Gevrey micro-local regularity of solutions, u∈C2(RN), of a system of nonlinear pdes of the form
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R.F. Barostichi 《Journal of Differential Equations》2009,247(6):1899-260
Let (x,t)∈Rm×R and u∈C2(Rm×R). We study the Gevrey micro-regularity of solutions u of the nonlinear equation
ut=f(x,t,u,ux), 相似文献
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根据 HL-2M 装置物理实验加热的需求,完成了总功率为 8MW 的电子回旋共振加热及电流驱动
(ECRH/ECCD)系统设计,开展了波源、传输及天线等关键部件研制。8MW ECRH/ECCD 系统,由 8 套 105GHz/
1MW/3s 波源系统、8 条内径为 63.5mm 的真空传输线及三套极向实时可控的发射天线构成。目前,已完成
ECRH/ECCD 系统关键部件研制及其相关的桌面与高功率性能测试。测试结果表明,微波源回旋管输出微波功率
达到1MW/3s,在真空度为 10‒2Pa 的过模波纹圆波导传输线中能低耗稳定传输,发射天线极向全量程角度转动响
应时间在 50ms 以内。 相似文献
7.
In this work we study the property of strong unique continuation, at a given point, for Gevrey solutions to homogeneous systems of PDE defined by complex, real-analytic vector fields in involution. We show that when the system is minimal at the point then the strong unique continuation property holds for Gevrey solutions of order σ∈[1,2] and, furthermore, when the minimality property fails to hold then there are non-trivial Gevrey flat solutions of any given order σ>1. The case of Gevrey order σ>2 is also studied for some particular classes of involutive systems. 相似文献
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de Farias RF de Souza JM de Melo JV Airoldi C 《Journal of colloid and interface science》2000,227(1):147-151
Polyaniline deposited on As(2)O(3) surface resulted in a new material, which was characterized by infrared spectoscopy, thermogravimetry, differential scanning calorimetry, scanning electron microscopy, X-ray diffraction, and cyclic voltammetry. The mass percentage of polymer deposited on oxide surface is approximately 13%. The scanning electron microscopy images as well as the X-ray diffraction patterns provided conclusive evidence that the oxide surface is coated by the polymer. The cyclic voltammograms of the polyaniline adsorbed on As(2)O(3) surface showed that the adsorbate exerts remarkable effects on redox processes on this oxide. The pure oxide exhibited two oxidation/reduction peaks at 0.25/-0.06 and 0.47/-0.25 V attributed tentatively to the processes As(2)O(3)(s)+6H(+)+6e(-)=2As(s)+3H(2)O and As(s)+3H(+)+3e(-)=AsH(3)(g), respectively. The polyaniline-coated sample exhibited a better-defined voltammogram in which the first oxidation peak of the oxide had its intensity increased about four times. Copyright 2000 Academic Press. 相似文献
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Dupont J Suarez PA De Souza RF Burrow RA Kintzinger JP 《Chemistry (Weinheim an der Bergstrasse, Germany)》2000,6(13):2377-2381
The crystal structure of 1-n-butyl-3-methylimidazolium tetraphenylborate molten salt (1) shows C-H-pi interactions between the hydrogens of the imidazolium cation and the phenyl rings of the tetraphenylborate anion. The imidazolium ring is surrounded by three tetraphenylborate anions that are connected with the same cation by C-H-pi (phenyl rings) interactions. The nearest inter-ion interaction is found between the N-CH-N proton of the cation and the B-phenyl centroid (2.349 A) with a nearly T-shaped geometry. The inter-ionic solution structure of 1 has been investigated by the detection of inter-ionic contacts in 1H NOESY NMR spectra between the protons of the cation and the anion. The 1H-NMR spectra of molten salt 1 is almost independent of its concentration in [D6]DMSO solution, the imidazolium proton chemical shifts are in the expected region and there are no observable NOE effects between the protons of the cation with those of the anion, indicating that 1 behaves in [D6]DMSO as a solvent-separated ion pair. In CDCl3 the 1H-NMR spectra of 1 are concentration dependent and all the imidazolium protons are shielded as compared with those observed in [D6]DMSO. Moreover, the 1H NOESY NMR spectra show all the peaks affected by the interaction between the protons of the imidazolium cation and those of the anion, indicating that in CDCl3 1 possesses a contact ion pair structure. The NCHN proton of the cation exhibits the greatest shielding (up to -4.5 ppm). an indication of the existence of C-H-pi interactions, even in solution. The calculated distance of this proton to the phenyl centroid is 2.3 A for a C-H -pi angle of 180 degrees. The apparent volumes for the cation and anion, calculated from the measured 13C-NMR relaxation times, increase from 38 and 140 A3 in [D6]DMSO to 360 and 600 A3 in CDCl3, respectively; this indicates the formation of floating aggregates of the type (1)(n) in CDCl3 via weak hydrogen bonds, with increasing concentration. 相似文献
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