排序方式: 共有28条查询结果,搜索用时 15 毫秒
1.
Application of TiO2-nanotubes/PbO2 as an anode for the electrochemical elimination of Acid Red 1 dye
Santos José Eudes L. de Moura Dayanne Chianca da Silva Djalma Ribeiro Panizza Marco Martínez-Huitle Carlos A. 《Journal of Solid State Electrochemistry》2019,23(2):351-360
Journal of Solid State Electrochemistry - In this study, galvanostatic electrolysis, through the use of the platinum supported on Ti (Ti/Pt) and Ti/TiO2-nanotubes/PbO2 anodes, was conducted in an... 相似文献
2.
Labiadh Lazhar Barbucci Antonio Carpanese Maria Paola Gadri Abdellatif Ammar Salah Panizza Marco 《Journal of Solid State Electrochemistry》2017,21(8):2167-2175
Journal of Solid State Electrochemistry - In this paper, the electrocatalytic properties of PbO2 and TiRuSnO2 anodes for direct and indirect electrochemical oxidation of a synthetic solution... 相似文献
3.
The binary path selection of droplets reaching a T junction is regulated by time-delayed feedback and nonlinear couplings. Such mechanisms result in complex dynamics of droplet partitioning: numerous discrete bifurcations between periodic regimes are observed. We introduce a model based on an approximation that makes this problem tractable. This allows us to derive analytical formulae that predict the occurrence of the bifurcations between consecutive regimes, establish selection rules for the period of a regime, and describe the evolutions of the period and complexity of droplet pattern in a cycle with the key parameters of the system. We discuss the validity and limitations of our model which describes semiquantitatively both numerical simulations and microfluidic experiments. 相似文献
4.
Nozawa K Gailhanou H Raison L Panizza P Ushiki H Sellier E Delville JP Delville MH 《Langmuir : the ACS journal of surfaces and colloids》2005,21(4):1516-1523
Control over the synthesis of monodisperse silica particles up to mesoscopic scale is generally made difficult due to intrinsic limitation to submicrometric dimensions and secondary nucleation in seeded experiments. To investigate this issue and overcome these difficulties, we have implemented single step processing by quantifying the effects of the progressive addition of a diluted tetraethyl orthosilicate solution in ethanol on the size and monodispersity of silica particles. Contrary to particles grown in seeded polymerization, monodisperse particles with size up to 2 microm were synthesized. Moreover, the particles exhibit a final diameter (d(f)), which varies with V(-1/3) over more than 2 orders of magnitude in rate of addition (V). On the basis of a kinetic study in the presence of addition showing that particle growth is limited by the diffusion of monomer species, we developed a diffusion-limited growth model to theoretically explain the observed d(f)(V) behavior and quantitatively retrieve the measured amplitude and exponent. Using a single parameter procedure, we can therefore predict and generate in the room temperature range, monodisperse particles of a targeted size by simply adjusting the rate of addition. 相似文献
5.
We study the behavior of a confined stream made of two immiscible fluids when it reaches a T junction. Two flow patterns are witnessed: the stream is either directed in only one sidearm, yielding a preferential flow pathway for the dispersed phase, or splits between both. We show that the selection of these patterns is not triggered by the shape of the junction nor by capillary effects, but results from confinement. It can be anticipated in terms of the hydrodynamic properties of the flow. A simple model yielding universal behavior in terms of the relevant adimensional parameters of the problem is presented and discussed. 相似文献
6.
We report on the design and realization of photonic integrated devices based on 3D organic microresonators (MR) shaped by an applied fluid mechanism technique. Such an interdisciplinary approach has been judiciously achieved by combining microfluidics techniques and thin-film processes, respectively, for the realizations of microfluidic and optical chips. The microfluidic framework with flow rates control allows the fabrication of microresonators with diameters ranging from 30 to 160 μm. The resonance of an isolated sphere in air has been demonstrated by way of a modified Raman spectroscopy devoted to the excitation of Whispering Gallery Modes (WGM). Then the 3D-MR have been integrated onto an organic chip and positioned either close to the extremity of a taper or alongside a rib waveguide. Both devices have proved efficient evanescent coupling mechanisms leading to the excitation of the WGM confined at the surface of the organic 3D-MR. Finally, a band-stop filter has been used to detect the resonance spectra of organic resonators once being integrated. Such spectral resonances have been observed with an integrated configuration and characterized with a Δλ = 1.4 nm free spectral range (FSR), appearing as stemming from a 78 μm-radius MR structure. 相似文献
7.
Controlled production of emulsions and particles by milli- and microfluidic techniques 总被引:1,自引:0,他引:1
The recent developments of soft lithography and microfluidic techniques now permit the manipulation of small quantities of fluids with very good control and reproducibility. These advances open a new “bottom-up” route to emulsification that paves the way to the fabrication of calibrated hierarchically organized emulsions and particles. In this article, we describe the microfluidic techniques elaborated for engineering emulsions and new dispersed materials and discuss their advantages over “top-down” approaches. We review and comment the high potentialities these techniques offer to emulsion and colloid science, to the development of high-throughput set-ups for chemistry, physics and biology. We illustrate them through a few examples taken from the current literature. 相似文献
8.
An increase of intensity of second harmonic generation is observed in p-nitrophenylhydrazine between room temperature and 77 K. The variation is present only when the applied laser field has a non-zero component parallel to the b edge of the unit cell. 相似文献
9.
A dynamic study of onion phases under shear flow: size changes 总被引:5,自引:0,他引:5
P. Panizza A. Colin C. Coulon D. Roux 《The European Physical Journal B - Condensed Matter and Complex Systems》1998,4(1):65-74
It has been shown that lyotropic lamellar phases under shear flow form structures corresponding to a close packed assembly
of monodisperse multilamellar vesicles (onions). The size, which is fixed by the shear rate, can vary from a few microns to
a tenth of a micron. In this study, we investigate for the first time the transient behaviour of size changes of onions under
shear flow by means of small angle light scattering, direct microscopic observations, and conductivity measurements. We evidence
two regimes: continuous and discontinuous. The nature of which (continuous or discontinuous) depends on the initial and final
shear rate, and can be described by a dynamic phase diagram.
Received: 14 November 1997 / Received in final form: 2 March 1998 / Accepted: 9 March 1998 相似文献
10.
We report that, when a train of confined droplets flowing through a channel reaches a junction, the droplets either are alternately distributed between the different outlets or all collect into the shortest one. We argue that this behavior is due to the hydrodynamic feedback of droplets in the different outlets on the selection process occurring at the junction. A "mean field" model, yielding semiquantitative results, offers a first guide to predict droplet traffic in branched networks. 相似文献