A liquid forced through an orifice into immiscible fluid ultimately breaks drops due to surface tension. Drop formation can occur right at the in a dripping process. Alternatively, inner form jet, which further downstream. The transition from jetting is not understood for coflowing streams, unlike case of drop air. We show that stream this be characterized by state diagram depends on capillary number outer and Weber fluid.

We describe new developments for the controlled fabrication of monodisperse emulsions using microfluidics. use glass capillary devices to generate single, double, and higher order with exceptional precision. These can serve as ideal templates generating well-defined particles functional vesicles. Polydimethylsiloxane microfluidic are also used picoliter-scale water-in-oil at rates high 10 000 drops per second. have great potential individual microvessels in high-throughput screening...

Microgel structures such as spherical microgel shells (picture on the upper left) and particles that incorporate quantum dots, magnetic nanoparticles, polymer microparticles (other images) have been prepared by a capillary microfluidic technique. Because these change their volume with changes in temperature, they may find application in, for example, drug delivery. Supporting information this article is available WWW under http://www.wiley-vch.de/contents/jc_2002/2007/z604206_s.pdf or from...

Colloidal dispersions have been studied for decades as a result of their utility in numerous applications and models molecular atomic condensed phases. More recently, number groups exploited such studies submicrometer-sized hydrogel particles (microgels) that environmentally tunable sizes. The experimental convenience tuning the dispersion's colloidal volume fraction while maintaining constant density provides clear advantage over more tedious employ traditional hard-sphere particles....

Transport of fluid through a pipe is essential for the operation macroscale machines and microfluidic devices. Conventional fluids only flow in response to external pressure. We demonstrate that an active isotropic fluid, composed microtubules molecular motors, autonomously flows meter-long three-dimensional channels. establish control over magnitude, velocity profile, direction self-organized correlate these structure extensile microtubule bundles. The inherently transition from...

We use double-emulsion drops to experimentally investigate the defect structures of spherical shells nematic liquid crystals. uncover a rich scenario coexisting dictated by unavoidable finite thickness even thinnest shell and variation around sphere. These are characterized varying number disclination lines pairs surface point defects on inner outer surfaces shell. In limit very thick structure ultimately merges with that bulk crystal drop.

Cylindrical liquid jets are inherently unstable and eventually break into drops due to the Rayleigh-Plateau instability, characterized by growth of disturbances that either convective or absolute in nature. Convective instabilities grow amplitude as they swept along flow, while at a fixed spatial location. Liquid nearly always convectively unstable. Here we show two-phase can breakup an instability depends on capillary number outer liquid, provided Weber inner is >O(1). We verify our...

We present a robust and straightforward approach for fabricating novel colloidosome system where colloidal particles are assembled to form shells on the surface of stimuli-responsive microgel scaffolds. demonstrate that structural properties can be controlled through particle size modulus, state supporting particles. This technique offers new way engineer colloidosomes, enabling fine control over their permeability wide range length scales.

We review a powerful regularization method, known as CONTIN, for obtaining the size distribution of colloidal suspensions from dynamic light scattering data. show that together with so-called L-curve criterion selecting optimal parameter, method correctly describes average and microgel independently characterized using small-angle neutron scattering. In contrast, we find when default process, where regularizer is selected via "probability to reject" results are not satisfactory.

The presumed ground state of a nematic fluid confined in cylindrical geometry with planar anchoring corresponds to that an axial configuration, wherein the director, free deformations, is along long axis cylinder. However, upon confinement lyotropic chromonic liquid crystals geometries, here we uncover surprising corresponding doubly twisted director configuration. stability this state, which involves significant can be rationalized by saddle-splay contribution energy. We show sufficient...

Impurities in crystals generally cause point defects and can even suppress crystallization. This general rule, however, does not apply to colloidal formed by soft microgel particles [Iyer ASJ, Lyon LA (2009) Angew Chem Int Ed 48:4562-4566], as, this case, the larger are able shrink join crystal a majority of smaller particles. Using small-angle X-ray scattering, we find limit large-particle concentration for spontaneous deswelling persist. We rationalize our data context those counterions...

We present a robust and straightforward method for fabricating remarkably responsive hydrogel scaffolds consisting of submicron-sized microgel particles. demonstrate that the particles assemble either through bridging or depletion interactions to yield structure swells deswells at macroscopic level in much shorter times as compared bulk polymer gel similar characteristics. This approach offers new way functional with controllable responsiveness applied stimuli excellent loading capability...

We study the nematic-smectic phase transition of a thermotropic liquid crystal confined to spherical shell. Far from temperature, ${T}_{\mathrm{NS}}$, we observe configuration with four $+1/2$ defects, as predicted by theory. Since in this case ${K}_{1}\ensuremath{\approx}{K}_{3}$, defects are at thinnest part shell minimize energy associated defect cores. By contrast, near where ${K}_{3}\ensuremath{\gg}{K}_{1}$, bend distortions become prohibited and organize themselves along great circle...

We stabilize nematic droplets with handles against surface-tension-driven instabilities using a yield-stress material as outer fluid and study the complex textures defect structures that result from competition between topological constraints elasticity of liquid crystal. uncover surprisingly persistent twisted configuration director inside when tangential anchoring is established at their boundaries, which we explain after considering influence saddle-splay on elastic free energy. For...

We use a simple method to generate toroidal droplets and study how they transform into spherical droplets. The relies on the viscous forces exerted by rotating continuous phase over liquid which is extruded from an injection needle; resultant jet forced close torus due imposed rotation. Once formed, transforms single or multiple spheres. Interestingly, we find there are two routes for this process depending aspect ratio of torus. For thin tori, classical hydrodynamic instabilities induce its...

The elastic modulus, G′p, of concentrated suspensions thermoresponsive microgel particles highlights transitions between glassy, liquidlike, and gel-like behavior as the temperature is varied. Approaching low critical solution particles, Tc ≈ 29 °C, material undergoes solid-to-liquid even above random close packing irrespective particle concentration. Detailed facts importance to specialist readers are published "Supporting Information". Such documents peer-reviewed, but not copy-edited or...