bluuebunny/crossref_metadata_2025_split huggingface dataset:
A Pd/Al2O3-based micro-reformer unit fully integrated in silicon technology for H-rich gas production
Authors: Bianchini M , Alayo N , Soler L , Salleras M , Fonseca L , Llorca J , Tarancon A 
Published: December 2019

Abstract
This work reports the design, manufacturing and catalytic activity characterization of a micro-reformer for hydrogen-rich gas generation integrated in portable-solid oxide fuel cells (μ-SOFCs). The reformer has been designed as a silicon micro monolithic substrate compatible with the mainstream microelectronics fabrication technologies ensuring a cost-effective high reproducibility and reliability. Design and geometry of the system have been optimized comparing with the previous design, consisting in an array of more than 7x103 vertical through-silicon micro channels perfectly aligned (50 μm diameter) and a 5 W integrated serpentine heater consisting of three stacked metallic layers (TiW, W and Au) for perfect adhesion and passivation. Traditional fuels for SOFCs, such as ethanol or methanol, have been replaced by dimethyl ether (DME) and the chosen catalyst for DME conversion consists of Pd nanoparticles grafted on an alumina active support. The micro-channels have been coated by atomic layer deposition (ALD) with amorphous Al2O3 and the influence of rapid thermal processing (RTP) on such film has been studied. A customized ceramic 3D-printed holder has been designed to measure the specific hydrogen production rates, DME conversion and selectivity profiles of such catalyst at different temperatures.
Magnetic Pendulum Arrays for Efficient Wireless Power Transmission
Authors: Mysore Nagaraja S P , Tok R U , Zhu R , Bland S , Propst A , Wang Y E 
Published: December 2019

Abstract
In this paper we would like to propose an innovative electromechanical transmitter called Magnetic Pendulum Array (MPA), for efficient wireless power transmission at Ultra Low Frequencies (ULF). We take advantage of the high Quality (Q) factor and low dissipation in the electromechanical system to demonstrate efficient power transfer. It has been shown that using Magnetic Pendulum arrays leads to about 10dB% higher power transfer efficiency at the resonance frequency of 447 Hz as compared to a coil of similar dimensions.
A mechanically tunable GHz passive voltage element using microstrip resonator
Authors: Ni Di , Ravi Adarsh , Vinaya Kumar K B , Lal Amit 
Published: December 2019

Abstract
The ability to detect very low RF signals can be used to wake-up a sensor node only when needed to sense or transmit data, reducing the sensor node power consumption. A passive voltage transforming stage from the antenna to a nano-watt receiver can be useful to reduce the minimum detectable RF signal. At high RF frequencies, the transformer is harder to implement owing to the low impedance of load capacitive loads. We demonstrate a gigahertz frequency range passive voltage transformer, using a mechanically tunable strip-line resonator at 1-2 GHz. The transformer exhibited a 19.5dB gain at 1.007 GHz and achieved gains over 19dB with load capacitances of 0.8-2.4pF. A piezoelectric AlN GHz transducer was also used to measure the gain of the resonator. An RF waveguide model has been developed which matches experiments well for both frequency and gain responses.
Development of thermoelectric thin films and characterization methods
Authors: Mori T , Aizawa T , Mitani S , Tsujii N , Ohkubo I , Tynell T , Kakefuda Y , Baba T , Mitome M , Kawamoto N , Golberg D 
Published: December 2019

Abstract
This work reports on the fabrication of thin films of inorganic thermoelectric materials like borides, germanides, manganese compounds, and characterization of their thermoelectric properties. We have utilized a unique high temperature molecular beam epitaxy (MBE) apparatus to grow hexaboride thin films and manganese germanides. Magnetic manganese based alloy thin films were also grown using sputtering, since we are interested in the possibilities of utilizing magnetism to develop thermoelectric materials.
Optimization of Carbon Electrodes for Solid-State E-Textile Supercapacitors
Authors: Hillier N , Yong S , Beeby S 
Published: December 2019

Abstract
The integration of flexible supercapacitors (FSC) into electronic textiles (e-textiles) offers a promising power source, capable of fast charge-discharge rates, high-power density and long lifetimes. The design parameters for such a device are varied and complicated, with the need for low weight, cheap production, breathability and low toxicity. This work presents the optimization of the carbon electrodes within a solid-state, single-layer textile supercapacitor that meets these device requirements. Three commercial activated carbons are investigated with different ratios of activated carbon to Carbon Black, at differing loading levels. The maximum areal capacitance observed was 23.6 mF.cm−2
Miniature, 3D-Printed, Monolithic Arrays of Corona Ionizers
Authors: Sun Zhumei , Velásquez–García Luis F 
Published: December 2019

Abstract
We report the design, fabrication, and characterization of the first 3D-printed, monolithic corona ionizer arrays (CIAs) in the literature. The CIAs are binder inkjet-printed in stainless steel 316L and have 5, 9, or 32 emitters (emitter pitch equal to 6 mm, 4 mm, or 2 mm, respectively); each emitter is 5 mm tall, with 1.7 mm diameter at the base and 300 μm diameter at the tip. Current-voltage data were collected in air with the emitter array biased negatively with respect to a counter-electrode for varying inter-electrode separation; the current divided by the bias voltage has a linear dependence with respect to the bias voltage minus the onset voltage –in agreement with the Townsend current-voltage law. 3D finite element simulation of the electrostatics of the densest CIA using the COMSOL Multiphysics evidences that the emitters at the periphery of the array have the highest electrical field, while a 1D electrohydrodynamic model implemented in the same software predicts a 400 μm-thick corona region surrounding the corona tip.
Generation of asymmetric incommensurable torque signals
Authors: Kurmann L. , Duarte J.L. 
Published: December 2019

Abstract
Asymmetric incommensurable torque signals can be achieved by exploiting magnetic nonpolar repulsion techniques, see also [1], aiming at designing kinetic energy harvester (KEH) systems. This paper confirms by using three different simulation methods that an asymmetric incommensurable torque signal is feasible to be reached, exploiting non-conservative magnet fields. All shown calculations are in full agreement with the classical Electromagnetic Theory. The first method (I) is based on time consuming full 3D FE generated torque and force signals. The second method (II) is using also FE generated torque and force signals, but they are calculated only in orthogonal directions, approximated with Fourier Series and normalized to provide 2D stiffness signals. The third approach (method III) focuses on filamentary current rings to calculate the magnetic field of permanent magnets (PM) to generate in a purely analytically way the same force and torque signals as in the previous methods. However, only speculation about the energy source as required to maintain the forecasted persistent torque can be given.
Graphene-porous semiconductor nanocomposites scalable synthesis for energy applications
Authors: Dupuy A , Sauze S , Jellite M , Arvinte R , Arès R , Boucherif A 
Published: December 2019

AbstractThe aim of this work is to develop a cost effective and scalable fabrication process for graphene-enhanced porous semiconductor nanocomposite (GPNC). This class of materials combines the remarkable properties of graphene with the unique properties of porous semiconductors, such as porous silicon (PSi) and porous germanium (PGe). The experimental results show that these nanocomposites are chemically resistant to most of the commonly used microfabrication solutions and have enhanced electrical and thermal properties. Besides, we demonstrate the potential of graphene-porous germanium nanocomposite (GPGNC) for energy storage application.
Hydrogen Evolution Catalytic Performance of Metal Doped MoS2
Authors: Leng X , Wang Y , Wang F 
Published: December 2019

Abstract
Metal doped Molybdenum disulphide (MoS2) has been synthesized through hydrothermal method. The layer distance of MoS2 has not changed due to the tiny doping amount of metal element while the hydrogen evolution catalytic performance has been modified. The structure and morphology has been observed through SEM and XRD pattern. Hydrogen evolution reaction has been carried out in a standard three electrode system and the results showed that doped MoS2 performed good catalytic activity. Both Co and Fe showed obvious improvement in the catalytic performance.
A cm-scale, low wind velocity and 250°C-compliant airflow-driven harvester for aeronautic applications
Authors: Gasnier P , Willemin J , Boisseau S , Goubault De Brugière B , Pillonnet G , Gomez B , Neyret I 
Published: December 2019

Abstract
This paper reports the design, fabrication, and testing of a centimeter-scale (Ørotor=35mm), 250°C-compliant microturbine for aeronautic applications. Dedicated to low-speed air flows (≈3 m/s and down to 2 m/s), this device is the first flow-driven harvester withstanding such high temperatures and high vibration levels (10
7
cycles at 20G). Furthermore, the proposed harvester exhibits the highest output power per unit cross sectional area compared to prior art in the cm-scale and low velocity ranges.
Wearable generator with rotating oscillating mass
Authors: Ortiz M , Fenollal E , Restrepo B , Espinoza A , Romero E 
Published: December 2019

Abstract
This paper reports the design, fabrication, and testing of a rotating, oscillating mass electromagnetic generator for wearable applications. This work presents a custom design architecture to evaluate the differences in generation output for swinging motion when driven at different frequencies, and load conditions. Body movement is characterized by large amplitude motion, such as the limbs when walking, whereas machine vibration displacement is relatively small and well catered with linear energy harvesters. The proposed study evaluates a rotational generator mounted on a swinging arm driven by a sinusoidal input motion to determine the parameters that lead to higher power output. Power measurement up to 0.25 μW was generated under sinusoidal input motion.
Dynamic Analysis of Electrostatic Energy Harvesting Device with Multi-step Structure
Authors: Guo Xinge , Zhang Yulong , Wang Fei 
Published: December 2019

Abstract
In this paper, the dynamic features of an electrostatic energy harvester with out-of-the-plane gap closing scheme has been studied with different stopper heights and surface potentials. The displacement and output power of the devices with various stopper heights have been simulated, measured and analysed and “pull-in” effect has been considered. The “pull-in” effect is observed for device with high surface potential, which limits the output power. And a decrease of output power for device with higher stoppers and same gap and acceleration is also noticed, which is different from the phenomenon observed previously. The dynamic analysis of the device will facilitate the design of electrostatic vibration based energy harvesters.
Equivalent circuit model of piezoelectric vibration energy harvesters composed of trapezoidal unimorph cantilevers
Authors: Umegaki Toshihito , Ito Takashi , Tan Goon , Kanno Isaku 
Published: December 2019

Abstract
We have constructed a time-resolved equivalent circuit model of the piezoelectric vibrational energy harvesters (PVEHs) with the trapezoidal unimorph structure not only to optimize the dimensional parameter of trapezoidal PVEHs but also to anticipate the output power by a variety of external vibrations. To calculate the output responses by arbitrary mechanical input accelerations such as impulses or sinusoidal, we have formulated simultaneous first order differential equations based on this model. In order to express dynamics with large amplitudes enough to drive actual devices such as micro-sensors with BLEs, we have considered the nonlinear effects, and successfully reproduced experiments by our calculations.
Determination of mechanical force generated by growing seed in inkjet 3D printed microdevice
Authors: Adamski K , Kawa B , Dziuban J , Walczak R 
Published: December 2019

Abstract
An inkjet 3D printed microdevice for germinating seed root and stalk driving force measurement is proposed. The device consists of two cantilever-type sensors for the forces monitoring. The cantilevers are first mechanically characterized by force-deflection measurements. Deflection of the cantilevers in the microdevice is determined by optical analysis of the captured “micropot” images. Then deflection is converted to force value. Successful monitoring of the root and stalk driving forces in different cultivation mediums was achieved.
Dynamics of direct hydrocarbon polymer electrolyte membrane fuel cells
Authors: Kong E H , Ronney P D , Surya Prakash G K 
Published: December 2019

Abstract
Hydrocarbons have 50-100 times higher energy per unit weight compared to commercially available batteries, thus harvesting only 10% of the energy from hydrocarbons could provide a far lighter energy source for portable electronic devices. With this motivation, the feasibility of using polymer electrolyte membrane fuel cells with propane fuel, operating at low temperatures (< 100˚C), was explored. It was interesting to note that there was a significant influence of the current history on the fuel cell performance. In particular, at higher current densities (>24 mA/cm2) the power output gradually decreases then rapidly “extinguishes” (i.e., produces no power). However, by employing an unconventional operating mode (load-interrupt) where the current is shut off for a short period of time and then reapplied, the average maximum power density increased to 11.6 mW/cm2. Furthermore, the extinction of the fuel cell can be further improved by seeding a small amount of unsaturated hydrocarbons (~2000ppm) into the fuel stream and can extend the lifetime of the fuel cell by more than 10 times.
Improved sensitivity of thin film sensor for humidity measurement inside a operating PEMFC
Authors: Hasegawa Noriyoshi , Otsuki Yota , Kurosu Masato , Araki Takuto 
Published: December 2019

Abstract
Water management inside a proton exchange membrane fuel cell (PEMFC) is an important issue for improving the performance of a PEMFC. It is necessary to understand water transport phenomena inside a PEMFC for water management. Especially humidity measurement near the membrane electrode assembly is indispensable. In order to measure the humidity, we fabricated the capacity type humidity sensor with thickness of 7 μm using micro-electro-mechanical system techniques. In addition, in order to measure the humidity locally, we reduced the parasitic capacitance by changing the shape of the sensor, and improved the sensitivity of the sensor by carrying out O2 plasma etching on the humidity sensitive layer. Finally, the improved sensor was inserted between the catalyst layer and micro porous layer inside a PEMFC, and the humidity inside it during power generation was measured to confirm that the sensor was functioning.
Microfabrication of a Silicon Turbopump with Embedded Thermal Isolation for a Rankine MEMS Heat Engine
Authors: Amnache Amrid , Fréchette Luc G. 
Published: December 2019

Abstract
This paper presents the fabrication of a silicon MEMS microturbopump with embedded thick thermal isolation, covering the key building blocks to incorporate thermally insulated zones in a multiple wafer stack, and the resulting device. Thermal insulation is a roadblock for the implementation of heat engines at the MEMS scale. To implement the Rankine cycle on a chip, insulation is required to prevent boiling of water in the pump while the turbine is exposed to high temperature vapour flows. To prevent heat from conducting through the silicon rotor, thick glass insulation was embedded into the rotor structure using glass molding and planarization. This composite rotor approach allows us to leverage the capabilities of silicon DRIE, while creating over 100 micron thick glass insulation between the turbine and the pump. Also, in-plane thermal insulation is required between the central pump zone and the surrounding fluid film bearings, fed with steam. This was accomplished by etching deep trenches in silicon to form an array of thin walls, followed by a thermal oxidation step that consumes the silicon walls and closes the trenches to form a deep monolithic oxide zone. These techniques were successfully implemented for the fabrication of a complete MEMS turbopump, which consists of a stack of 4 silicon wafers and one glass wafer, and a total of 18 lithography/etch steps.
A narrow-band and ultra-low-power 433 MHz wake-up receiver
Authors: Koeble S , Heller S , Woias P 
Published: December 2019

Abstract
For the design of wireless sensor nodes (WSNs) the inclusion of a wake-up receiver becomes interesting as soon as an asynchronous bidirectional communication between the WSN and its host is mandatory, to e.g. reprogram the WSN or to trigger the delivery of data. For these purposes the use of the WSNs standard RF interface is not suitable in most cases, as the high power consumption of the same may drain the WSNs battery or overload the capabilities of an integrated energy harvesting module. To solve this principal conflict between flexibility and power consumption, we present the design and characterization of an ultra-low-power wake-up receiver. The concept is based on an optimized modulation/demodulation concept, to achieve a high RF sensitivity and narrow-band operation at the same time. The final device works in the license-free 433 MHz frequency band, with a high RF sensitivity of -63.4 dBm, an ultra-low power consumption of 8.7 µW, and with a low supply voltage of 2 V only.
A Papertronic Sensing System for Rapid Visual Screening of Bacterial Electrogenicity
Authors: Tahernia Mehdi , Mohammadifar Maedeh , Choi Seokheun 
Published: December 2019

Abstract
In this work, we report a papertronic sensing system with the ability to achieve easy, rapid, and sensitive characterization of bacterial electrogenicity from a single drop of culture. Paper was used as a device substrate that inherently produces favorable conditions for easy, rapid, and sensitive and potentially high-throughput controlling of a microbial liquid sample. Through an innovative microscale device structure and a simple transistor amplifier circuit directly integrated into a single sheet of paper substrate, a powerful sensing array was constructed, resulting in the rapid and sensitive characterization of bacterial electrogenicity from a microliter sample volume. The microbial current generations were amplified by the transistor providing power to a 4-wide LED circuit board indicator bar for the direct visual readout with the naked eyes. Depending on bacterial electrogenicity, the LED intensity was changed. We validated the effectiveness of the sensor using two known bacterial electrogens (wild-type S. oneidensis and P. aeruginosa) and hypothesis-driven genetically modified P. aeruginosa mutant strains.
Glucose oxidase bioelectrodes in devices implanted in living plants for energy applications.
Authors: Galindo-de-la-Rosa J. , Hernández-Torres A. , Araiza-Ramírez M.G. , Arriaga L.G. , Ledesma-García J. 
Published: December 2019

Abstract
The growth of the world population and the lack of energy supply have led to the development of technologies to obtain alternative energy that has a minimal environmental impact, as is the case of fuel cells. In this work, the development of electrodes using glucose oxidase enzyme immobilized with functionalized carbon nanofibers on graphite rods is proposed for its application in a fuel cell implanted in living plants, specifically in cacti. The purpose is to convert solar energy to chemical and then, to electric energy, carrying out the glucose oxidation contained in these plants. The use of a living plant as a fuel cell comes from the idea of taking advantage of more efficiently the conversion of chemical energy, which comes from the plant’s photosynthesis until is converted into electrical energy.
Thin-Film π-Type Micro TEG Using Vacuum/Insulator-Hybrid Isolation with Convex-Shape Hot-Plate Module Structure for Wearable Device Applications
Authors: Shiotsu Y , Seino T , Chiwaki N , Sugahara S 
Published: December 2019

Abstract
Design optimization and performance of a micro thermoelectric generator (μTEG) using human body heat are investigated. A newly introduced thin-film π-type μTEG module structure using vacuum/insulator-hybrid thermal isolation with the convex-shape hot plate is useful to achieve a high thermal resistance of the module and also to suppress the unwanted heat flow passing through the supportive wall structure for the vacuum isolation. The optimum design of this μTEG module can exhibit sufficiently high output power suitable for a power source of self-powered wearable devices.
A Voltage-Boost Rectifier Circuit for Energy Harvesting from Environmental Vibrations
Authors: Tohyama Y , Honma H , Ishihara N , Sekiya H , Toshiyoshi H , Yamane D 
Published: December 2019

Abstract
We propose a VBR (voltage-boost rectifier) circuit based on the 0.18-μm Si CMOS (complementary metal oxide semiconductor) technology, which is designed for vibrational energy harvesters utilizing environmental vibrations. The VBR employs a single-end Dickson type charge-pump topology, and the circuit would be realized as a monolithic chip. The evaluation results obtained by multi-physics simulations on a circuit simulator reveal that the proposed circuit can deliver boosted DC voltage from the input of sub-threshold AC voltage.
Design of a MEMS relay based on SOI fabrication technology
Authors: Schwarz M. , Lambrecht F. , Bauer A. , Seidel H. 
Published: December 2019

Abstract
The deployment of MEMS relay for high power switching applications requires a matrix-like arrangement of many single MEMS relay units. For consistent performance the sameness of the individual switches representing the array is crucial. We present the design, simulation and fabrication of a MEMS relay based on silicon-on-insulator (SOI) technology. The measurement results show high accordance with simulations confirming the predictability and thereby the homogeneity of SOI-based MEMS relays.
Laser-bonding of FEP/FEP interfaces for a flexible manufacturing process of ferroelectrets
Authors: Flachs D. , Emmerich F. , Roth G.-L. , Hellmann R. , Thielemann C. 
Published: December 2019

Abstract
This paper presents an optimized laser-bonding process for piezoelectric energy-harvesters based on thin fluorinated-ethylene-propylene (FEP) foils, using an ultra-short-pulse (USP) laser. Due to the minimized thermal stress in the material during bonding, achieved by pulse durations of few picoseconds, we created seams down to 40 µm width without generating holes in the 12.5 µm thick FEP-foils. Using a galvanometer scanning system allowed for fast bonding-speed up to several centimeters per second, making the process also suitable for large structures and areas. The achieved bond strength of the seams under influence of shearing stress was examined using tensile testing, which showed a sufficient strength of about 25 % of the maximum strength of an unbonded, single layer of FEP.
Ethanol Tolerant Catalyst Based in Platinum and Silver in Graphene
Authors: Estrada-Solís M. J. , López-González B. , Guerra-Balcázar M. , Cuevas-Muñiz F.M. 
Published: December 2019

Abstract
In this work, the use of the electrochemical deposit PtAg on the glassy carbon modified with graphene (PtAg/G) is proposed. The electrochemical test (Rotatory Disc Electrode, RDE) showed a better performance to reduce oxygen for PtAg/G compared to a similar material obtained in Vulcan carbon (PtAg/V). The reduction potential is around 0.82 V versus RHE in PtAg/G compared to 0.77 V versus RHE in PtAg/V. The PtAg/G has a smaller particle size, this was attributable to the better distribution of active graphene sites.