Diffusion-sensitized magnetic resonance imaging probes the cellular structure of the human brain, but the primary microstructural information gets lost in averaging over higher-level, mesoscopic tissue organization such as different orientations of neuronal fibers. While such averaging is inevitable due to the limited imaging resolution, we propose a method for disentangling the microscopic cel...

Mesoporous fluorinated organosilicate films were synthesized from tetramethoxysilane and perfluoroalkylsilanes (RO)3Si-R’ [R ~ Me, Et; R’ ~ (CH2)2CF3, (CH2)2(CF2)5CF3, or (CH2)2(CF2)7CF3] under acidic conditions in the presence of cetyltrimethylammonium chloride (CTACl) by sol–gel spin-coating. Calcination at 350 uC allowed the removal of surfactants without destroying the other organic content...

Water famously expands upon freezing, foreshadowed by a negative coefficient of expansion of the liquid at temperatures close to its freezing temperature. These behaviors, and many others, reflect the energetic preference for local tetrahedral arrangements of water molecules and entropic effects that oppose it. Here, we provide theoretical analysis of mesoscopic implications of this competition...

Martensite/ferrite (M/F) interface damage largely controls failure of dual-phase (DP) steels. In order to predict the and assess ductility DP steels, accurate models for M/F interfacial zones are needed. Several have been proposed in literature, which however do not incorporate underlying microphysics. It has recently suggested that (lath) martensite substructure boundary sliding dominates init...

Advanced finite element techniques in simulation of the materials behavior under mechanical loading are reviewed. Advantages, limitations and perspectives of different approaches to the simulation of deformation, damage and fracture of materials taking into account their microand mesostructure are analyzed. Development of the methods of simulation of different aspects of the materials behavior ...

We report the synthesis and characterization of a novel mesoporous material with a face-centered cubic (fcc) symmetry and intrinsic bimodal pores. Moreover, an icosahedral (ICO) mesostructure with both meso- and macroscale 5-fold symmetry is observed. We propose a hard-sphere packing (HSP) mechanism for the formation of mesoporous materials by assuming preformed robust surfactant/silicate compo...

Research on the properties and applications of molecules doped into sol-gel-derived silica matrices has expanded rapidly. This Account begins with a brief review of the use of the dopant molecules as probes of the changes that occur as the system evolves from the initial sol to the final xerogel during the formation of monoliths, thin films, and mesostructured films. Methods of deliberately pla...

Mesostructured silica waveguide arrays were fabricated with a combination of acidic sol-gel block copolymer templating chemistry and soft lithography. Waveguiding was enabled by the use of a low-refractive index (1.15) mesoporous silica thin film support. When the mesostructure was doped with the laser dye rhodamine 6G, amplified spontaneous emission was observed with a low pumping threshold of...