Use of Magnetomechanical Effect for Energy Harvesting and Data Transfer.

The presented paper describes a method where, with the use of a dedicated SMART Ultrasonic Resonant Power System (SURPS) developed by the authors, a power and data transfer between two devices can be performed at the same time. The proposed solution allows power to be supplied to the sensor, located in a hardly accessible place, with simultaneous data transfer in a half-duplex way (e.g., "question-response"). The power transmission mechanism is based on the excitation of a construction with a sinusoidal wave, with an actuator transforming this wave into useful, electrical power through a harvester device. Data transfer is achieved with the use of the F2F (Frequency Double Frequency) procedure, which is a kind of frequency modulation. To receive optimized parameters for each construction, an original software is developed, which allows the selection of the proper type of actuator, modulation, and frequency.

Rapid Demagnetization of New Hybrid Core for Energy Harvesting.

This paper presents the results obtained using the rapid demagnetization method in the case of an NdFeB magnet and a new hybrid core. The developed core consists of three basic elements: an NdFeB magnet, Terfenol-D, and a specifically developed metallic alloy prepared by means of a suction casting method. The main goal of proposing a new type of core in the event of rapid demagnetization is to partially replace the permanent magnet with another material to reduce the rare-earth material while keeping the amount of generated electricity at a level that makes it possible to power low-power electrical devices. To "capture" the rapid change of magnetic flux, a small number of coils were made around the core. However, the very low voltage level at very high current required the use of specialized electronic transducers capable of delivering a voltage level appropriate for powering a microprocessor system. To overcome this problem, a circuit designed by the authors that enabled voltage processing from low impedance magnetic circuits was used. The obtained results demonstrated the usefulness of the system at resonant frequencies of up to 1 MHz.

Laser-Induced Generation of Hydrogen in Water by Using Graphene Target.

A new method of hydrogen generation from water, by irradiation with CW infrared laser diode of graphene scaffold immersed in solution, is reported. Hydrogen production was extremely efficient upon admixing NaCl into water. The efficiency of hydrogen production increased exponentially with laser power. It was shown that hydrogen production was highly efficient when the intense white light emission induced by laser irradiation of graphene foam was occurring. The mechanism of laser-induced dissociation of water is discussed. It was found that hydrogen production was extremely high, at about 80%, and assisted by a small emission of O2, CO and CO2 gases.

Laser induced visible and infrared emission of a tungsten filament.

The measurements of laser induced emission (LIE) of a tungsten filament upon irradiation with the focused beam of a CW IR laser diode are reported. It was found that the emission occurred in visible and infrared range. The influence of the applied DC electric field significantly affected the intensity of LIE of the tungsten filament. The origin of LIE is discussed in terms of multiphoton ionization of tungsten W+ atoms assisted by light emission due to the intervalence charge transfer in the tungsten hybrid domain (W, W+).

Laser-Induced Hydrogen Generation from Methanol with Graphene Aerogel as the Target.

The present work demonstrates a new concept of the efficient generation of hydrogen from methanol by the continuous wave laser diode irradiation of an immersed graphene aerogel (GA) scaffold as the target. It was observed that the process occurred very intensively when it was assisted by bright white light emission in the spot of a laser-irradiated GA scaffold. The yield of hydrogen emission increased exponentially with the applied laser power. The light emission was assisted by the intense production of H2, CH4, and CO gases. It was found that with increasing excitation laser power, the H2 generation increased at the expense of CO. It is shown that the volume of CO decreases because of the formation of C2 molecules and CO2 gases. The mechanism of the laser-driven dissociation of methanol was discussed in terms of the violent ejection of hot electrons from the GA surface as a result of the laser-induced light emission of the graphene target.