Nano-textured polymers for future architectural needs

Corresponding author: Prof. Dr. Dirk J. Broer, Professor at Eindhoven University of Technology, Chemical Engineering & Chemistry, Department of Functional Organic Materials & Devices (SFD), Helix building STO 0.34, Den Dolech 2, 5612 AZ Eindhoven, The Netherlands. Tel.: +31 40 247 5875, Mob: +31 6 51662354; E-mail: [email protected] The rapid developments in molecular sciences like nanotechnology and self-organizing molecular systems generate a wealth of new materials and functions. In comparison to electronics the application in architecture remains somewhat underexposed. New functionalities in optics, responsive mechanics, sensing and adjustable permeation for gases and water might add to new opportunities in providing for personal comfort and energy management in houses and professional buildings. With a number of examples we demonstrate how complex but well-controlled molecular architectures provide functionalities worthwhile of being integrated in architectural designs. Optical coatings are capable of switching colors or reflectivity, creating possibilities for design but also for the control of thermal transmission through windows. They respond to temperature, light intensity, or both. Selectively-reflective thin polymer layers or paint pigments can be designed to switch between infrared and visible regions of the solar spectrum. Coatings can be designed to change their topology and thereby their appearance, of interest for in-house light management, or just for aesthetic appeal. Plastic materials can be imbued with the property of autonomous sun tracking and provided morphing behavior upon contact with moisture or exposure to light. Many of these materials need further developments to meet the requirements for building integration with respect to robustness, lifetime, and the like, which will only be accomplished after demonstration of interest from the architectural world

Aerodynamics Flapping-Flight Robotic Bird using Unsteady Lifting-Line Method

The Robird is a bird-like drone, or ornithopter, that generates lift and thrust by flapping and pitching its wings, which performance resembles that of a Peregrine falcon. This paper describes an extension, from steady flow to unsteady flow, of Prandtl’s Lifting-Line method to predict the unsteady lift, thrust, pitching-moment, root-bending moment, required-power and propulsive-efficiency of the robotic bird. The extension comprises the derivation of the Kutta-Joukowski Theorem for unsteady flow, an unsteady trailing-edge Kutta condition and the representation of the wake as a stationary transpiration-type of planar surface carrying a time-dependent dipole distribution. Its instantaneous strength is obtained from the spanwise distribution of the circulation of the lifting line at earlier times. For the cases considered, the numerical method predicts that the section-lift, section-thrust, section-pitching-moment and section-required-power of the wing vary in time. During flapping flight, the cycle-averaged section-lift and section-thrust, as well as the cycle-averaged overall lift and thrust, are mostly positive. The spanwise distributions of cycle-averaged sectional aerodynamic quantities like circulation, lift, etc., as well as the corresponding span-integrated overall quantities and the propulsive efficiency, depend on flight parameters Strouhal number, but not all on pitch amplitude, cycle-averaged effective angle-of-attack nor phase difference between pitching and flapping. The topology of the wake in terms of the unsteady wake dipole distribution, as well as its corresponding vortex distribution, predicted by the unsteady-lifting-line method depend on all flight parameters. The paper provides the relation between wake topology and the generation of lift and thrust

Annual Reports of the Board of Selectmen Treasurer, and Supervisor of Schools of the Town of Greene, for the Year Ending March 6, 1896

An in situ method for sealing an array of pre-filled micro-cavities, such as encountered in electrophoretic displays, is presented. The technique, which is based on photoembossing, forms a hermetic seal between the cover and the cavity walls. The seal locations are defined by ultraviolet exposure through a photolithographic mask, forming a latent image overlapping with the locations of the cavity walls. During a thermal development step, while the cover is mounted on top of the micro-cavities, the seal evolves and makes firm contact with the cavity walls. This technology is demonstrated to be insensitive to small deviations in cavity height, flatness of the cover and thin fluid films remaining between the cover and the top of the cavity walls. In the past, these aspects made it difficult to effectively seal large-area devices