among the all parameters affecting the performance of a downhole de-oiling hydrocyclone, the investigation of internal flow field deserves more attempts especially in the petroleum industry. in this study, the effects of inlet flow rate, inlet oil volume fraction, and oil droplet diameter on the separation efficiency and pressure drop ratio have been investigated along the hydrocyclone body. al...

The paper proposes a set of technical tools for solving the problem ensuring uniformity measurements micro- and nanoparticles. To do this, it is necessary to ensure traceabilityof particle size unit length – meter, as well equivalent diameters used in various dispersed media (aerosols suspensions). traceability diameter proposed use nanomeasuring machine with an atomic force microscope probing ...

In studying the fluid flow and heat transfer in microchannels, various claims have been made regarding transition at Reynolds numbers significantly below 2300. As a first step in identifying the reasons for such early transition, the effect of entrance geometry on the pressure drop and transition to turbulence is studied experimentally in a conventional channel of 1.9 cm inner diameter. Four ty...

Combination of dynamic and static light scattering experiments gives important information on structural and dynamic properties of polymer solutions and colloidal suspensions. However, the analysis of light scattering experiments in turbid media is highly complicated due to the presence of multiple scattering. Recently, a one-beam set-up has been proposed and it could be shown that the cross co...

This study demonstrates that the hydrodynamic phenomena taking place inside the capillary limits the frequency range of voltage pulses for stable single event electrospraying SEE , when the meniscus/cone size is defined by the inner diameter of the nozzle. For the analysis of SEE, we used a one-dimensional model describing the displacement and oscillations of the liquid inside the nozzle. The f...

In this work, partially hydrolyzed thermoresponsive polyoxazoline was used for complexation with DNA. The resulting polyelectrolyte complex particles were characterized by dynamic and electrophoretic light scattering. They showed narrow size distribution and hydrodynamic diameter of 183 ±5 nm at 65 °C. To improve stability of the system at physiological temperature, the particles were coated wi...

A new siRNA delivery system using a cationic glyco-star polymer is described. Spermine-modified 8-arm amylose star polymer (with a degree of polymerization of approximately 60 per arm) was synthesized by chemoenzymatic methods. The cationic star polymer effectively bound to siRNA and formed spherical complexes with an average hydrodynamic diameter of 230 nm. The cationic 8-arm star polymer comp...

Molecular dynamics studies of nanometer-sized rigid grains, droplets and bubbles in nanometer-sized pores indicate that the drag force may have a hydrodynamic form if the moving object is dense and small compared to the pore diameter. Otherwise, the behavior is nonhydrodynamic. The terminal speed is insensitive to whether the falling droplet is made of liquid or a solid. The velocity profiles w...

A theoretical model based on the molecular interactions between a growing tumor and a dynamically evolving blood vessel network describes the transformation of the regular vasculature in normal tissues into a highly inhomogeneous tumor specific capillary network. The emerging morphology, characterized by the compartmentalization of the tumor into several regions differing in vessel density, dia...

Temperature- and electric field-responsive polymer-conjugated polystyrene beads, termed smart beads, are designed to isolate cancer cells. In smart beads, the reversible "on-off" antigen-antibody reaction and dielectrophoresis force on an electrode are accomplished to realize "on-off" remote manipulation of smart beads and cancer cells. Both the zeta-potential and the hydrodynamic diameter of t...