We use micro particle image velocimetry (mPIV) and fluorescence microscopy techniques to characterize microscale segmented gas–liquid flow at low superficial velocities relevant for chemical reactions with residence times of up to several minutes. Different gas–liquid microfluidic channel networks of rectangular cross section are fabricated in poly(dimethylsiloxane) (PDMS) using soft lithograph...

The development of sensor materials which gas sensitivity activates under light illumination is great importance for the design portable analyzers with low power consumption. In present work a ZnO/CsPbBr3 nanocomposite based on nanocrystalline ZnO and colloidal cubic-shaped perovskite CsPbBr3 nanocrystals (NCs) capped by oleic acide oleylamine was synthesized. individual obtained are characteri...

We investigate the thermal fluctuations of the colloidal gas-liquid interface subjected to a shear flow parallel to the interface. Strikingly, we find that the shear strongly suppresses capillary waves, making the interface smoother. This phenomenon can be described by introducing an effective interfacial tension that increases with the shear rate. The increase of sigma(eff) is a direct consequ...

We study experimentally and numerically a (quasi-)two-dimensional colloidal suspension of self-propelled spherical particles. The particles are carbon-coated Janus particles, which are propelled due to diffusiophoresis in a near-critical water-lutidine mixture. At low densities, we find that the driving stabilizes small clusters. At higher densities, the suspension undergoes a phase separation ...

We report theoretical and numerical evaluations of the phase diagram for patchy colloidal particles of new generation. We show that the reduction of the number of bonded nearest neighbors offers the possibility of generating liquid states (i.e., states with temperature T lower than the liquid-gas critical temperature) with a vanishing occupied packing fraction (phi), a case which can not be rea...

The influence of interface porosity on the wetting properties of colloid-polymer mixtures is studied within density functional theory for the Asakura-Oosawa-Vrij model at the surface of a quenched hard-sphere matrix. While the porosity hardly changes the location of the transition from partial to complete wetting at colloidal bulk gas-liquid coexistence, the onset of wetting, as signaled by the...

The mean spherical approximation ~MSA! was used to investigate the phase behavior of charged colloidal systems with and without added salt. The competition between cohesive Coulomb interactions and stabilizing entropic and hard-core interactions controls the stability of the system and under certain circumstances, a liquid–gas-type phase transition can occur. The critical parameters and phase d...

We examine sedimentation density profiles of star polymer solutions as an example of colloidal systems in sedimentation equilibrium that exhibit reentrant melting in their bulk phase diagram. Phase transitions between a fluid and a fluid with an intercalated solid are observed below a critical gravitational strength alpha*. Characteristics of the two fluid-solid interfaces in the density profil...

Pd nanoparticles were fabricated on graphene oxide (GO) using a deposition-precipitation method with a glow discharge plasma reduction at room temperature. Argon was employed as the plasma-generating gas. The novel plasma method selectively reduces the metal ions. The graphene oxide has no change with this plasma reduction according to the Fourier transform infrared analysis. The Pd nanoparticl...

silicon and aluminum sources are most important reactants in the synthesis of zeolite. the use of the silicon source has an important effect on the crystallization of zeolites. also, it can change the properties of the end product. this work reports the influence of three common commercial silica sources such as colloidal silica (ludox am-30), fumed silica and water glass on the crystallinity o...