Stability of an electrified liquid jet approaching to critical point

This article reports the linear stability analysis of a thermodynamic-transcritical jet sprayed to a radial electrical field. An asymptotic approach was used to obtain the stability solution of a supercritical jet subjected to electrical field. In order to obtain the solutions for the electrified supercritical jet, the surface tension was decreased and consequently led the increase in Weber number in the linear governing equation of subcritical charged jet. To investigate the role of surface tension and electric stress playing in the destabilizing process when approaching the critical point, the energy budget is performed by tracing the energy sources. It was found that, when the Weber number is increased to a sufficiently large value, the solution will become an asymptotic value, which can be considered as a solution under the supercritical conditions. The electric stress can increase both the maximum growth rate and the dominant wave number of electrified supercritical jet, that is, higher electrical field intensity would enhance the instability of the electrified supercritical jet and decrease the wavelength of the disturbances.

Диэлектрический отклик керамических твердых растворов 16BiScO-=SUB=-3-=/SUB=--42PbMg-=SUB=-1/3-=/SUB=-Nb-=SUB=-2/3-=/SUB=-O-=SUB=-3-=/SUB=--42PbTiO-=SUB=-3-=/SUB=- в электрическом поле

Some results of studying the dielectric and electromechanical properties of ceramic 16BiScO_3–42PbMg_1/3Nb_2/3O_3–42PbTiO_3 relaxor ferroelectric samples in electrical fields (0 < E < 20 kV/cm) are presented. An appreciable decrease in the dielectric permittivity with time, and the disappearance of hysteresis in the dependence of the longitudinal strain on the electrical field intensity were revealed in the fields exceeding the coercive field ( E > 10 kV/cm) and explained by the induced ferroelectric phase transition. The field-induced phase (presumably, tetragonal) was shown to be unstable and partially ordered. A nonmonotonical character demonstrated by the dielectric permittivity–time dependences of the studied ceramics unlike the other relaxor ferroelectrics was explained by the coexistence of glassy and ferroelectric phases.

The Optical Properties of Nano-Materials and Electromagnetic Wave Propagation Visualized with MATLAB

The course of electromagnetic fields and waves has properties of abstract concept, strong theory and complex calculation, thus this course is difficult to study and understand, and then is also difficult to teach. In order to make the understanding of the course easier, MATLAB software is used as a platform in classroom teaching of electromagnetic fields and waves. This paper mainly discusses the electrical field intensity distribution of media sphere materials and the properties of electromagnetic wave propagation with MATLAB software. The optical properties of dielectric-metal core-shell multi-layered nano-shell are also studied with Laplace's equation. To enrich the teaching content and improve a better teaching effect, the optical property of nano-materials and electromagnetic wave propagation are visualized with MATLAB software, which makes the properties of nano-materials and electromagnetic wave propagation understand easily.

Electrohydrodynamics of particle-covered drops

We experimentally investigate the effect of surface-absorbed colloidal particles on the dynamics of a leaky dielectric drop in a uniform DC electric field. Depending on the particle polarizabilty, coverage and the electrical field intensity, particles assemble into various patterns such as an equatorial belt, pole-to-pole chains or a band of dynamic vortices. The particle structuring changes droplet electrohydrodynamics: under the same conditions where a particle-free drop would be a steady oblate spheroid, the belt can give rise to unsteady behaviours such as sustained drop wobbling or tumbling. Moreover, particle chaining can be accompanied by prolate drop deformation and tip-streaming.

Research of Organophosphorus Scale Inhibitors Treatment by Photoelectric Catalysis Oxidation Method

Photoelectric catalysis oxidation process, which employs UV lamp as light source,TiO2 electrical as anode and Pt as cathode, has been used for degrading Organophosphorus scale inhibitors.The effects of additional electrical field intensity and pH of the solution on the removal rate of organophosphorus are investigated. The results show that the best additional voltage during the process of photo electrocatalysis is 8V, pH=8.0, and reaction time 10min, the organophosphorus removal rate of HEDP reaches 93.35%, the organophosphorus removal rate of PCAC reaches 96.0%.