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We use confocal microscopy to study an equilibrated crystal--liquid interface in a colloidal suspension. Capillary waves roughen the surface, but locally the intrinsic interface is sharply defined. We use local measurements of the structure and dynamics to characterize the intrinsic interface, and different measurements find slightly different widths of this interface. In terms of the particle diameter d, this width is either 1.5d (based on structural information) or 2.4d (based on dynamics), both not much larger than the particle size. This work is the first direct experimental visualization of an equilibrated crystal--liquid interface. surface tension | capillary waves | confocal microscopy

We use a confocal microscope to study the aging of a bidisperse colloidal glass near rough and smooth boundaries. Near smooth boundaries, the particles form layers, and particle motion is dramatically slower near the boundary as compared to the bulk. Near rough boundaries, the layers nearly vanish, and particle motion is nearly identical to that of the bulk. The gradient in dynamics near the boundaries is demonstrated to be a function of the gradient in structure for both types of boundaries. Our observations show that wall-induced layer structures strongly influence aging. [ABSTRACT FROM AUTHOR]

An NAMFIS deconvolution analysis for laulimalide in DMSO-d6 is performed to examine the conformational energy surface of laulimalide. 15 laulimalide conformations are identified that can be classified into 5 different families, Supine, Convex, Cobra, Strech, and Concave motifs.

Electric fields produced by coplanar point charges have often been represented by field line diagrams that depict two-dimensional slices of the three-dimensional field. Serious problems with these 'conventional' field line diagrams (CFLDs) have been overlooked. Two of these problems, 'equatorial clumping' and 'false monopole moment,' occur because a two-dimensional slice lacks information vital to the accurate representation of an inherently three-dimensional field. Equatorial dumping causes most CFLDs to exhibit unphysical behavior such as irregular spacing between field lines terminating on negative charges. CFLDs can also mistakenly indicate that a neutral charge distribution has a significant monopole moment. Such phenomena make the visual estimation of local field strengths impossible and render CFLDs of little utility for representing three-dimensional fields. While these 'projection' problems can be avoided by using two-dimensional field line diagrams to represent two-dimensional (1/r) electric fields, or by using three-dimensional field line diagrams to represent three-dimensional fields, other forms of distortion generally remain.

Electrostatic interactions have affected the immersion depth of nanoparticles into an interface, which is proved by measuring the diffusion constant of charged nanoparticles at a sodium chloride solution/air interface. The results have shown that the location of nanoparticles at interfaces is determined by an intricate interplay between the electrostatic properties of the solution/air interface, the solution/solid interface and the classical contact angle.

A genetic toolbox of natural and engineered protein modules is used to create several materials that form reversible networks in the presence of [Ca.sup.2+]. The modular framework can be extended to create a variety of new sensing materials using modules from the diverse array of signaling pathways that are mediated by reversible protein-protein interactions.

A study on the laboratory demonstrations that manifests properties of squishy substances, explained as materials that are not clearly solid, liquid, or gas, is presented.

Confocal microscopy is used in the study of colloidal gels, glasses, and binary fluids. We measure the three-dimensional positions of colloidal particles with a precision of approximately 50 nm (a small fraction of each particle's radius) and with a time resolution sufficient for tracking the thermal motions of several thousand particles at once. This information allows us to characterize the structure and the dynamics of these materials in qualitatively new ways, for example, by quantifying the topology of chains and clusters of particles as well as by measuring the spatial correlations between particles with high mobilities. We describe our experimental technique and describe measurements that complement the results of light scattering. OCIS codes: 110.2960, 110.0180, 180.1790.