Search

Among various strategies for energy harvesting in micro and meso-scale, Piezoelectric Energy Harvesting System (PEHS) brought about an ideal prospect of green source of energy to power electrical devices at low driving voltage. As it is expected, Micro Electro-Mechanical Systems (MEMS) and Wireless Sensor Nodes (WSN) are considered as substantial applications of PEHS in diverse fields such as biomedical, vehicles and security system. However like most of mechatronics systems a PEHS can be optimized mechanically and electrically to achieve more electrical power besides adaptive performance regardless of ambient vibration variation. Considering electrical standpoint instead of mechanical concern, in this paper after a glance at analysis and modeling of a designed PEHS an electrical optimization in interface circuit will be examined and tested. Using off the shelf components and a relatively simple structure of this optimized and self-powered interface circuit substituted for Standard Energy Harvesting Circuit (SEHC) are the striking features of this scheme. [ABSTRACT FROM PUBLISHER]

All scientific instruments in the field of astronomy and lasers are now using adaptive mirrors to improve the spot size quality. For X-ray mirrors, which are used in grazing angle, the design of such mirrors has to be specific to take into account the rectangular shape of the mirror. We introduce the differences between traditional mechanical active optics and adaptive mirrors based on a bimorph structure with piezoelectric ceramics and give the detail of the last achievements. © 2007 American Institute of Physics [ABSTRACT FROM AUTHOR]

A new macromolecular crystallographic facility developed by GM/CA-CAT is operational at the Advanced Photon Source (APS). The facility consists of three beamlines: two lines based on the first “hard” dual canted undulators and one bending magnet beamline. The ID lines are operational, and the BM line is being commissioned. Both insertion device (ID) beamlines are independently tunable over a wide energy range. The inboard ID lines have been upgraded with a new insertion device to provide enhanced performance for MAD phasing experiments near the selenium and bromine K-edges. The ID line monochromators’ crystals are indirectly, cryogenically cooled for improved performance and reliability. Focusing is achieved by long bimorph mirrors in a Kirkpatrick-Baez geometry. This paper describes the design of the beam lines and the optical characterization of the mirrors and monochromators. © 2007 American Institute of Physics [ABSTRACT FROM AUTHOR]