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For an evaporating colloidal suspension in which the evaporation velocity exceeds the sedimentation velocity, particles will accumulate at the solvent−air interface. If neither diffusion nor convection can disperse this accumulation, it is expected to grow into a colloidal multilayer several microns thick. We observe that the thickness of colloidal crystals vertically deposited from 1 m diameter polystyrene latex suspensions of 0.002 ≤ ≤ 0.008 increases linearly with distance in the growth direction and that these thickness profiles are consistent with their growth from a horizontal colloidal layer accumulated beneath the solvent−air interface. We describe a means for performing vertical deposition at growth rates slower than the evaporation rate by adding solvent to the bottom of the colloidal suspension and observe that halving the growth rate of vertical deposition increases both the thickness and the reflectivity of the resulting colloidal crystals, effects indistinguishable from those of doubling the concentration of the colloidal suspension, data also consistent with the colloidal crystals' growth from a horizontal layer of particles beneath the interface. If sufficiently little reorganization is involved as particles move from this horizontal layer to the vertically deposited colloidal crystal, slow vertical deposition of polymer microspheres might be thought of as the Langmuir−Blodgett transfer of a horizontal colloidal crystal onto a vertical substrate. Colloidal crystals deposited using both high concentration and slowed growth can have peak IR reflectance in excess of 80%, exceeding most published values. These observations provide a conceptual framework for engineering vertically deposited colloidal crystals that combine thickness with good optical performance.

Quartz surfaces and colloidal silica particles were derivatized with a poly(methyl methacrylate) copolymer containing spirobenzopyran (SP) photochromic molecules in the pendant groups at a concentration of 20 mol %. Two-photon near-IR excitation (∼780 nm) was then used to create chemically distinct patterns on the modified surfaces through a photochromic process of SP transformation to the zwitterionic merocyanine (MC) isomer. The derivatized colloids were approximately 10 times more likely to adsorb onto the photoswitched, MC regions. Surface coverage and adsorption kinetics have been compared to the mean-field model of irreversible monolayer adsorption.

Missing availability of reliable and specific landscape data may pose substantial restrictions to successful exploitation of remote sensing data and fast implementation of GIS (Geo-Information Systems). The possibilities to document conditions with high spacialdisticntion is made between \lsspacial\rs (three-dimensional) and \lsspatial\rs (two-dimensional) resolution at a given time and to review changing aspects by different disciplines represent opportunities for complex environmental programs.

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