6 research outputs found
Self-assembled plasmonic templates produced by microwave annealing: applications to surface-enhanced Raman scattering
Perhaps the simplest method for creating metal nanoparticles on a substrate is by driving their self-assembly with the thermal annealing of a thin metal film. By properly tuning the annealing parameters one hopes to discover a recipe that allows the pre-determined design of the NP arrangement. However, thermal treatment is known for detrimental effects and is not really the manufacturer's route of choice when it comes to large-scale applications. An alternative method is the use of microwave annealing, a method that has never been applied for metal processing, due to the high reflectance of microwave radiation at the surface of a metal. However, in this work we challenge the widely used nanostructuring methods by proving the microwave's annealing ability to produce plasmonic templates, out of extremely thin metal films, by simply using a domestic microwave oven apparatus. We show that this process is generic and independent of the deposition method used for the metal and we further quantify the suitability of these plasmonic templates for use in surface-enhanced Raman scattering applications
Efficient and Rapid Photocatalytic Reduction of Hexavalent Chromium Achieved by a Phloroglucinol-Derived Microporous Polymeric Organic Framework Solid
A microporous polymeric organic framework (POF) based on phloroglucinol (phlo-POF) was for the first time evaluated on photoreduction and removal processes of hexavalent chromium (Cr6+) from aqueous solutions. The phlo-POF synthesis was based on reaction of phloroglucinol and terephthalaldehyde under hydrothermal conditions. Structural and chemical characterization was performed using UV-vis-NIR diffuse reflectance spectroscopy (DRS), FT-infrared spectroscopy, and thermogravimetric methods, while surface area analysis was employed to determine other physical and surface properties. Batch experiments were conducted on contaminated water to determine the rate and extent of Cr6+ removal and its immobilization by the phlo-POF material. The kinetic studies showed a rapid removal of Cr6+ ions from the water in the presence of the phlo-POF, best described by the zero-order kinetic model. The efficiency of the material with UV-C irradiation on Cr6+ reduction was compared with a well-studied material, the Degussa P-25 TiO2 catalyst, and found to be ∼200% higher. Cycle experiments verify the successful reuse of the phlo-POF photocatalyst for at least ten times for Cr6+ reduction
Review Update on Topical Therapy for Psoriasis
© 2018, Springer Science+Business Media, LLC, part of Springer Nature. Purpose of Review: Studies show frequent usage but low adherence rates and poor satisfaction from topical therapy for psoriasis. These were attributed to low efficacy, inconvenience of application, and poor cosmetic quality for different body parts. Recent Findings: Multicenter surveys on patients suggest a two-way holistic approach, where patients convey what bothers them most and doctors explain how products address specific concerns. New rapid response targeted topical agents, in cosmetically acceptable preparations, applied less often, are undergoing efficacy and safety studies, ideally on large populations up to 1 year or more. Until available, this review addresses gaps in knowledge on how to maximize effects of emollients, used alone, with physiologic lipids, or as base for active topical therapy. Summary: Updates—on how psoriasis skin becomes itchy, red, dry, thick, and scaly from inflammation and barrier defects—explain clinical responses to the physical, chemical, and functional properties of psoriasis topical therapies