An established aspect of force transmission in quasistatic deformation of granular media is the existence of a dual network of strongly versus weakly loaded particles. Despite significant interest, the regulation of strong and weak forces through the contact network remains poorly understood. We examine this aspect of force transmission using data on microstructural fabric from: (I) three-dimen...

OBJECTIVE We aimed to investigate the effects of silanation time on the shear bond strength (SBS) of metal brackets on gold alloy in a silicoating procedure and compare the SBS of metal brackets on gold alloy and enamel. METHODS Type III gold alloy plates were sandblasted with 30-µm silicon dioxide. Excess particles were removed with gentle air after silica coating, and silane was applied. Ma...

UNLABELLED To evaluate bond strengths of different resin cements to two aluminum oxide-based ceramics. METHODS One hundred ten ceramic cylinders were produced and given four different surface treatments. Resin cement cylinders were then bonded to the ceramic cylinders using different resin cements and the bond strength was determined by shear testing to the breaking point. We were thus able t...

The imidazole-4,5-dicarboxylic acid scaffold is readily derivatized with amino acid esters to afford symmetrically- and dissymmetrically-disubstituted imidazole-4,5-dicarboxamides with intramolecularly hydrogen bonded conformations that predispose the presentation of amino acid pharmacophores. In this work, a total of 45 imidazole-4,5-dicarboxamides bearing amino acid esters were prepared by pa...

The use of a recently developed cation-exchange HPLC packing material for the separation of hemoglobin types in human blood has been investigated. Adult and newborn hemolysates from normal individuals and from subjects with hemoglobin disorders were analyzed using a weak cation carboxymethyl-bonded phase on 5-micron-particle-size silica. Elution was accomplished using a Bistris (2-[bis(2-hydrox...

Time-resolved sum frequency generation (tr-SFG) reveals that the vibrational energy relaxation rate of O-H stretching of dilute HDO in D(2)O at the silica interface is markedly different from that of bulk water. As compared to the bulk liquid, the vibrational lifetime (T(1)) of HDO is shorter at the charged surface than in the bulk, but longer at the neutral surface. The vibrational decoupling ...