Phospholipid molecules are composed of multipolar headgroup and two electrically neutral hydrocarbon tails. The inverted hexagonal phase (HII ) belongs to the biologically most significant non-lamellar phospholipid phases in biomembranes. Hence the geometric properties and conditions of transition to the HII phase are nowadays widely studied. In our derivation of the free energy of lipid monola...

Hexagonal NaYbF4:Tm 3+ upconversion nanoparticles hold promise for use in high contrast near-infrared-tonear-infrared (NIR-to-NIR) in vitro and in vivo bioimaging. However, significant hurdles remain in their preparation and control of their morphology and size, as well as in enhancement of their upconversion efficiency. Here, we describe a systematic approach to produce highly controlled hexag...

Monodisperse emulsion droplets with a high volume fraction form crystalline phases that can potentially serve as adjustable photomasks in photolithography. Such photomasks were prepared using a microfluidic device in which a flow-focusing junction, side channels, and a reservoir were connected in series. Transparent oil droplets were generated in a dye-containing continuous water phase at the f...

Hexagonal NaYbF4:Tm(3+) upconversion nanoparticles hold promise for use in high contrast near-infrared-to-near-infrared (NIR-to-NIR) in vitro and in vivo bioimaging. However, significant hurdles remain in their preparation and control of their morphology and size, as well as in enhancement of their upconversion efficiency. Here, we describe a systematic approach to produce highly controlled hex...

2014 A new series of polar mesogens exhibits both a smectic B phase and a ribbon phase Sc. In this series, an incommensurate hexatic B phase has also been found. In this phase, a long wavelength modulation of the dipolar orientation is superimposed over the in-layer 2D hexagonal array. The structural features of this new phase are compared to those of the normal hexatic B and Sc phases. J. Phys...

Crystals of KC0PO4 were obtained by growth in a gel of tetramethoxysilane/water at 64 °C. The hexagonal crystals have space group P 63, a = 18.206(1), c = 8.5135(8) [Ä], V = 2443.8(4) [A3]. Z = 24. The structure was solved by single crystal X-ray diffraction methods. The struc­ ture is isotypic with a-K Z nP 04. It comprises an ordered three dimensional network of alter­ nating CoÖ4 and P 0 4 t...

In this study, physical vapor deposition (PVD) Ti-Cr-N coatings were deposited at two different temperatures 100 and 400ºC on hardened and tempered tool steel substrates. The influence of the applied deposition temperature on the physical and mechanical properties of coatings such as roughness, thickness, phase composition, hardness and Young’s modulus were evaluated. Phase compositions were st...

Reports of the antiviral activity of aliphatic alcohols led us to investigate the effects of aliphatic alcohols, from 10 to 20 carbons in length, on the phase transition behaviour of model phospholipids and on the fusion of influenza to liposomes. Contrary to the effects of many other antiviral agents, we find that alcohols are potent promoters of the inverted hexagonal phase. However, we also ...

Transition metals Ti, Zr, and Hf have a hexagonal close-packed structure (α) at ambient conditions, but undergo phase transformations with increasing temperature and pressure. Of particular significance is the high-pressure hexagonal ω phase which is brittle compared to the α phase. There has been a long debate about transformation mechanisms and orientation relations between the two crystal st...

Phase diagrams are determined by Monte Carlo lattice simulations for idealized symmetric and asymmetric surfactant molecules mixed with single-site "oil" and "water" molecules. At high concentrations (above 20%) of surfactant, the simulations show the self assembly of liquid crystalline phases, including smectic, hexagonal, BCC sphere packings, and Ia3d gyroid cubic phases. The locations of the...