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Porous Architecture (porous + architecture)
Selected AbstractsPorous Polymer Coatings: a Versatile Approach to Superhydrophobic SurfacesADVANCED FUNCTIONAL MATERIALS, Issue 12 2009Pavel A. Levkin Abstract Here, a facile and inexpensive approach to superhydrophobic polymer coatings is presented. The method involves the in situ polymerization of common monomers in the presence of a porogenic solvent to afford superhydrophobic surfaces with the desired combination of micro- and nanoscale roughness. The method is applicable to a variety of substrates and is not limited to small areas or flat surfaces. The polymerized material can be ground into a superhydrophobic powder, which, once applied to a surface, renders it superhydrophobic. The morphology of the porous polymer structure can be efficiently controlled by composition of the polymerization mixture, while surface chemistry can be adjusted by photografting. Morphology control is used to reduce the globule size of the porous architecture from micro down to nanoscale thereby affording a transparent material. The influence of both surface chemistry as well as the length scale of surface roughness on the superhydrophobicity is discussed. [source] Quantification of soil structural changes induced by cereal anchorage failure: Image analysis of thin sectionsJOURNAL OF PLANT NUTRITION AND SOIL SCIENCE, Issue 3 2007Sacha J. Mooney Abstract Cereal anchorage failure, or lodging, is the permanent displacement of a crop from the vertical and results in significant annual yield losses globally. Several factors have been identified as contributors to this phenomenon but the precise mechanisms of failure are still largely unknown because of difficulties in observing these processes as they occur in situ. To identify potential soil management practices to minimize losses associated with cereal root failure, an understanding of the nature of root-soil interactions attributed to lodging is needed. An experiment was conducted that involved field impregnation and subsequent thin sectioning of lodged and unlodged root-soil complexes from contrasting soils, cereal crops, and management practices to elucidate the effects of lodging on soil structure and porous architecture. Using image analysis, size and distribution of pores in soils were quantified at both meso- (100,30 ,m) and microscales (<30 ,m). A significant effect of lodging on porosity was recorded whereby lodging reduced total porosity through compaction created by movement of the stem base, although this was variable among soil types. Pore-size distributions comprehensively supported these trends since alteration in the relative frequency of pores within specific size classes was clearly observed. The effects of lodging were more pronounced at the mesoscale because the data were more susceptible to variations created by natural soil heterogeneity at the microscale. These data suggested that sideways movement of the subterranean stem within the soil is a significant factor which is likely to affect the propensity for a cereal plant to lodge, indicating soil strength in the upper part of the soil profile is crucial. [source] Biomimetic Nanostructures: Diatomaceous Lessons in Nanotechnology and Advanced Materials (Adv. Mater.ADVANCED MATERIALS, Issue 29 200929/2009) The cover picture shows a series of SEM and AFM images of silica structures from several different diatom species. These images demonstrate remarkable structural diversity and unique porous architectures of diatoms justifying their status as the world's smallest nanofabrication factories. Further details can be found in the article by Nicolas Voelcker and co-workers on p. 2947. [source] Porous silicon as a cell interface for bone tissue engineeringPHYSICA STATUS SOLIDI (A) APPLICATIONS AND MATERIALS SCIENCE, Issue 5 2007Wei Sun Abstract A novel cell interface has been constructed on porous silicon. We have demonstrated that nano- to macro-scale porous architectures have promising osteoconductive potentials. Macroporous silicon (pore opening 1,2 µm) is especially favorable for osteoblast adhesion, growth, protein synthesis and mineralization. An electronic/optoelectronic controllable medical implant with both scaffolding and drug delivery functions may be created for orthopaedic tissue engineering with this material. (© 2007 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) [source] | ||||||||||