Ferrofluid drop impacts and Rosensweig peak formation in a non-uniform magnetic field.

Vertical drop impacts of ferrofluids onto glass slides in a non-uniform magnetic field have been studied using high-speed photography. Outcomes have been classified based on the motion of the fluid-surface contact lines, and formation of peaks (Rosensweig instabilities) which affect the height of the spreading drop. The largest peaks are nucleated at the edge of a spreading drop, similarly to crown-rim instabilities in drop impacts with conventional fluids, and remain there for an extended time.

Atomic Layer Deposition on Dispersed Materials in Liquid Phase by Stoichiometrically Limited Injections.

Atomic layer deposition (ALD) is a well-established vapor-phase technique for depositing thin films with high conformality and atomically precise control over thickness. Its industrial development has been largely confined to wafers and low-surface-area materials because deposition on high-surface-area materials and powders remains extremely challenging. Challenges with such materials include long deposition times, extensive purging cycles, and requirements for large excesses of precursors and expensive low-pressure equipment.

Preclinical studies evaluating the effect of semifluorinated alkanes on ocular surface and tear fluid dynamics.

Purpose: Dry eye disease (DED) is one of the most prevalent ocular surface disorders that presents clinically. Recently, the semifluorinated alkane (SFA) perfluorohexyloctane (NovaTears; EvoTears) entered the market for the management of evaporative DED, while perfluorobutylpentane has been used as a vehicle to enhance ocular drug delivery. This study evaluated the mechanisms by which SFAs might improve therapeutic outcomes in DED.

Observation of Transient Overcritical Currents in YBCO Thin Films using High-Speed Magneto-Optical Imaging and Dynamic Current Mapping.

The dynamics of transient current distributions in superconducting YBaCuO thin films were investigated during and immediately following an external field ramp, using high-speed (real-time) Magneto-Optical Imaging and calculation of dynamic current profiles. A number of qualitatively unique and previously unobserved features are seen in this novel analysis of the evolution of supercurrent during penetration. As magnetic field ramps up from zero, the dynamic current profile is characterized by strong peaks, the magnitude of which exceed the conventional critical current density (as determined from static current profiles).

Analysis of low-field isotropic vortex glass containing vortex groups in YBa2Cu3O(7-x) thin films visualized by scanning SQUID microscopy.

The glass-like vortex distribution in pulsed laser deposited YBa2Cu3O(7-x) thin films is observed by scanning superconducting quantum interference device microscopy and analysed for ordering after cooling in magnetic fields significantly smaller than the Earth's field. Autocorrelation calculations on this distribution show a weak short-range positional order, while Delaunay triangulation shows a near-complete lack of orientational order. The distribution of these vortices is finally characterised as an isotropic vortex glass.