Reusable Ionogel-based Photo-actuators in a Lab-on-a-disc

This paper describes the design, fabrication and performance of a reusable ionogel-based photo-actuator, in-situ photopolymerised into a lab-on-a-disc microfluidic device, for flow control. The ionogel provides an effective barrier to liquids during storage of reagents and spinning of the disc. A simple LED (white light) triggers actuation of the ionogel for selective and precise channel opening at a desired location and time. The mechanism of actuation is reversible, and regeneration of the actuator is possible with an acid chloride solution. In order to achieve regeneration, the Lab-on-a-Disc device was designed with a microchannel connected perpendicularly to the bottom of the ionogel actuator (regeneration channel). This configuration allows the acid solution to reach the actuator, independently from the main channel, which initiates ionogel swelling and main channel closure, and thereby enables reusability of the whole device.Economía y Competitividad), Spain. This project has receivedfunding from the European Union Seventh Framework Programme(FP7) for Research, Technological Development and Demonstrationunder grant agreement no. 604241. JS and FBL acknowledge fund-ing support from Gobierno de Espa˜na, Ministerio de Economía yCompetitividad, with Grant No. BIO2016-80417-P and personallyacknowledge to Marian M. De Pancorbo for letting them to use herlaboratory facilities at UPV/EHU. A.T., L.F., and D.D. are grateful forfinancial support from the Marie Curie Innovative Training Net-work OrgBIO (Marie Curie ITN, GA607896) and Science FoundationIreland (SFI) under the Insight Centre for Data Analytics initiative,Grant Number SFI/12/RC/2289

Non-linear optical frequency conversion crystals for space applications

Reliable, long term operation of high-power laser systems in the Earth orbit is not a straightforward task as the space environment entails various risks for optical surfaces and bulk materials. The increased operational risk is, among others, due to the presence of high energy radiation penetrating the metallic shielding of satellites and inducing absorption centers in the bulk of optical components, and vacuum exposure which can deteriorate coating performance. Comprehensive testing for analyzing high-energy radiation effects and mitigation procedures were performed on a set of frequency conversion crystals and are discussed in this paper. In addition to a general resistance to space environmental effects, the frequency conversion crystals were subjected to a comparative analysis on optimum third harmonic efficiency, starting from pulsed 1064 nm laser radiation, with the goal of exceeding a value of 30 %. Concomitant modeling supported the selection of crystal parameters and the definition of crystal dimensions

Modeling of wireless remote shape control for beams using nonlinear photostrictive actuators

AbstractPhotostrictive materials produce mechanical strain when irradiated by ultraviolet light, thus may be used in wireless remote control of smart microstructures. This paper presents an investigation into modelling and static shape control of beams with nonlinear photostrictive actuators. Governing equations of beams bonded with photostrictive actuator patches are derived to study the interaction between the photostrictive actuators and the host beams. An analytical solution method is presented to solve the governing equations of the beams with discretely distributed photostrictive actuators. An iterative procedure is developed to find optimal light intensities in photostrictive actuators that best match the actuated shape to the desired one. An example is given to illustrate the model and shape control of a beam with PLZT actuators

Space science/space station attached payload pointing accommodation study: Technology assessment white paper

Technology assessment is performed for pointing systems that accommodate payloads of large mass and large dimensions. Related technology areas are also examined. These related areas include active thermal lines or power cables across gimbals, new materials for increased passive damping, tethered pointing, and inertially reacting pointing systems. Conclusions, issues and concerns, and recommendations regarding the status and development of large pointing systems for space applications are made based on the performed assessments

Carrier-Envelope Offset Stabilized Ultrafast Diode-Pumped Solid-State Lasers

Optical frequency combs have been revolutionizing many research areas and are finding a growing number of real-world applications. While initially dominated by Ti:Sapphire and fiber lasers, optical frequency combs from modelocked diode-pumped solid-state lasers (DPSSLs) have become an attractive alternative with state-of-the-art performance. In this article, we review the main achievements in ultrafast DPSSLs for frequency combs. We present the current status of carrier-envelope offset (CEO) frequency-stabilized DPSSLs based on various approaches and operating in different wavelength regimes. Feedback to the pump current provides a reliable scheme for frequency comb CEO stabilization, but also other methods with faster feedback not limited by the lifetime of the gain material have been applied. Pumping DPSSLs with high power multi-transverse-mode diodes enabled a new class of high power oscillators and gigahertz repetition rate lasers, which were initially not believed to be suitable for CEO stabilization due to the pump noise. However, this challenge has been overcome, and recently both high power and gigahertz DPSSL combs have been demonstrated. Thin disk lasers have demonstrated the highest pulse energy and average power emitted from any ultrafast oscillator and present a high potential for the future generation of stabilized frequency combs with hundreds of watts average output power

Recent Developments in Tough Hydrogels for Biomedical Applications

A hydrogel is a three-dimensional polymer network with high water content and has been attractive for many biomedical applications due to its excellent biocompatibility. However, classic hydrogels are mechanically weak and unsuitable for most physiological load-bearing situations. Thus, the development of tough hydrogels used in the biomedical field becomes critical. This work reviews various strategies to fabricate tough hydrogels with the introduction of non-covalent bonds and the construction of stretchable polymer networks and interpenetrated networks, such as the so-called double-network hydrogel. Additionally, the design of tough hydrogels for tissue adhesive, tissue engineering, and soft actuators is reviewe

Advances in Plasma Diagnostics and Applications

Plasma can be generated via the combination of energy-inducing fragmentation, ionization, and excitation of molecular. Such processes occur throughout the life of the plasma, resulting in a wide variety of atomic and molecular species, which can be electrically charged, energetically excited, highly reactive, or any combination of these states. Plasma diagnostics can demonstrate important discharge characteristics and the mechanisms of plasma-induced processes. Parameter’s dynamic range spans many orders of magnitude, and spatial/temporal scales significantly vary during plasma source configurations. Many diagnostic techniques have been developed to characterize plasma, including scattering techniques, intensified charge-coupled device cameras, laser-based methods, optical emission spectroscopy, mass spectrometry, electron paramagnetic resonance spectroscopy, gas chromatography, etc. Although various mature diagnostic technologies for plasma discharges have been developed, there are still many challenges. The measurement precision is not only affected by the diagnostic equipment/ techniques, but also by the plasma discharge itself. In many applications, direct measurements of the parameters of interest are still not possible. In addition, the plasma environments in application processes are unusually complex, and their reactions are still not fully understood. Plasma can exist in a variety of forms due to discharge modes resulting from different means of creation, resulting in a wide range of applications. This brings together many research fields, including physics, engineering, chemistry, biology, and medicine

Artificial Muscles

Course material for "Artificial Muscles" e-course

Integration of functional materials into microfluidic devices for fluidic control and sensing

165 p.El agua es una fuente clave para el buen estado de las personas y, en la naturaleza, es una fuente nutritiva esencial responsable del crecimiento de la vegetación. Por ello, la monitorización de la calidad del agua es de gran importancia para la sociedad. En esta tesis se pretende contribuir a un futuro donde sensores altamente autónomos y eficaces son capaces de medir y compartir la información de la calidad de nuestro medio ambiente, en particular, de las diferentes matrices de agua. En este sentido, se han desarrollado diferentes módulos para contribuir con bajo coste y tecnología de rápida fabricación a la monitorización continuada de la calidad del agua. Para conseguir reducir los costes asociados a la producción de componentes convencionales, se han implementado materiales inteligentes dentro de dispositivos microfluídicos para conseguir el control fluídico y sensórico

Microelectromechanical Systems and Devices

The advances of microelectromechanical systems (MEMS) and devices have been instrumental in the demonstration of new devices and applications, and even in the creation of new fields of research and development: bioMEMS, actuators, microfluidic devices, RF and optical MEMS. Experience indicates a need for MEMS book covering these materials as well as the most important process steps in bulk micro-machining and modeling. We are very pleased to present this book that contains 18 chapters, written by the experts in the field of MEMS. These chapters are groups into four broad sections of BioMEMS Devices, MEMS characterization and micromachining, RF and Optical MEMS, and MEMS based Actuators. The book starts with the emerging field of bioMEMS, including MEMS coil for retinal prostheses, DNA extraction by micro/bio-fluidics devices and acoustic biosensors. MEMS characterization, micromachining, macromodels, RF and Optical MEMS switches are discussed in next sections. The book concludes with the emphasis on MEMS based actuators