When Compactness Meets Flexibility: Basic Coaxial SIW Filter Topology for Device Miniaturization, Design Flexibility, Advanced Filtering Responses, and Implementation of Tunable Filters

Large-scale energy storage systems (ESS) are nowadays growing in popularity due to the increase in the energy production by renewable energy sources, which in general have a random intermittent nature. Currently, several redox flow batteries have been presented as an alternative of the classical ESS; the scalability, design flexibility and long life cycle of the vanadium redox flow battery (VRFB) have made it to stand out. In a VRFB cell, which consists of two electrodes and an ion exchange membrane, the electrolyte flows through the electrodes where the electrochemical reactions take place. Computational Fluid Dynamics (CFD) simulations are a very powerful tool to develop feasible numerical models to enhance the performance and lifetime of VRFBs. This review aims to present and discuss the numerical models developed in this field and, particularly, to analyze different types of flow fields and patterns that can be found in the literature. The numerical studies presented in this review are a helpful tool to evaluate several key parameters important to optimize the energy systems based on redox flow technologies.

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Microwave tunable filters and nonreciprocal devices using magnetic nanowires

Proceedings of the 2001 1st IEEE Conference on Nanotechnology. IEEE-NANO 2001 (Cat. No.01EX516) ◽

10.1109/nano.2001.966430 ◽

2002 ◽

Cited By ~ 4

Author(s):

A. Saib ◽

D. Vanhoenacker-Janvier ◽

J.-P. Raskin ◽

A. Crahay ◽

L. Huynen

Keyword(s):

Tunable Filters ◽

Magnetic Nanowires

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Expanding 3D Nanoprinting Performance by Blurring the Electron Beam

Micromachines ◽

10.3390/mi12020115 ◽

2021 ◽

Vol 12 (2) ◽

pp. 115

Author(s):

Lukas Seewald ◽

Robert Winkler ◽

Gerald Kothleitner ◽

Harald Plank

Keyword(s):

Electron Beam ◽

Direct Write ◽

Design Flexibility ◽

Individual Branch ◽

Inclination Angles ◽

3D Architecture ◽

20 Nm ◽

Surface Morphologies ◽

Nm Range ◽

Mechanical Rigidity

Additive, direct-write manufacturing via a focused electron beam has evolved into a reliable 3D nanoprinting technology in recent years. Aside from low demands on substrate materials and surface morphologies, this technology allows the fabrication of freestanding, 3D architectures with feature sizes down to the sub-20 nm range. While indispensably needed for some concepts (e.g., 3D nano-plasmonics), the final applications can also be limited due to low mechanical rigidity, and thermal- or electric conductivities. To optimize these properties, without changing the overall 3D architecture, a controlled method for tuning individual branch diameters is desirable. Following this motivation, here, we introduce on-purpose beam blurring for controlled upward scaling and study the behavior at different inclination angles. The study reveals a massive boost in growth efficiencies up to a factor of five and the strong delay of unwanted proximal growth. In doing so, this work expands the design flexibility of this technology.

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Intermodulation distortion and power handling in RF MEMS switches, varactors, and tunable filters

IEEE Transactions on Microwave Theory and Techniques ◽

10.1109/tmtt.2003.809650 ◽

2003 ◽

Vol 51 (4) ◽

pp. 1247-1256 ◽

Cited By ~ 139

Author(s):

L. Dussopt ◽

G.M. Rebeiz

Keyword(s):

Rf Mems ◽

Tunable Filters ◽

Intermodulation Distortion ◽

Mems Switches ◽

Power Handling ◽

Rf Mems Switches

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Smart DRA for beam width and orientation control

Frequenz ◽

10.1515/freq-2020-0013 ◽

2020 ◽

Vol 74 (11-12) ◽

pp. 383-392

Author(s):

Rajveer S. Yaduvanshi ◽

Richa Gupta ◽

Saurabh Katiyar

Keyword(s):

Radiation Pattern ◽

High Efficiency ◽

Beam Width ◽

Beam Control ◽

Design Flexibility ◽

Compact Size ◽

Close Proximity ◽

Cellular Communication Network ◽

Arc Shape ◽

Broadside Radiation

AbstractSmartdielectric resonator antenna (DRA) having beam control mechanism is anew area to be explored by antenna researchers. Proposed new geometry DRA has low loss, design flexibility, high efficiency, compact size and desired radiated beam control. Developing beam control in new geometry DRAs is investigated for the first time in this letter. Unique technique for beam control and beam width control is proposed using pit top and mount top DRA. Gain is controlled from 5.0 to 9.98 dBi and beam is controlled from ±30° to ±70° in broadside radiation pattern. U shape pit DRA has maximum directive gain of 9.98 dBi and efficiency 98% at 5.8 GHz frequency. Measured and simulated results of radiation pattern and reflection coefficient are found to be in close proximity. Hardware of U shape pit top DRA, mount top DRA, left side arc top DRA, right side arc shape top DRA is developed and investigated. Mobile and cellular communication network need wide coverage, hence large beam width is required. Narrowing of beam width at higher order mode is also achieved.

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FEBID 3D-Nanoprinting at Low Substrate Temperatures: Pushing the Speed While Keeping the Quality

Nanomaterials ◽

10.3390/nano11061527 ◽

2021 ◽

Vol 11 (6) ◽

pp. 1527

Author(s):

Jakob Hinum-Wagner ◽

David Kuhness ◽

Gerald Kothleitner ◽

Robert Winkler ◽

Harald Plank

Keyword(s):

Volume Growth ◽

Point Of View ◽

High Fidelity ◽

Direct Write ◽

General Picture ◽

3D Space ◽

Design Flexibility ◽

Substrate Temperatures ◽

Very High ◽

Comprehensive Discussion

High-fidelity 3D printing of nanoscale objects is an increasing relevant but challenging task. Among the few fabrication techniques, focused electron beam induced deposition (FEBID) has demonstrated its high potential due to its direct-write character, nanoscale capabilities in 3D space and a very high design flexibility. A limitation, however, is the low fabrication speed, which often restricts 3D-FEBID for the fabrication of single objects. In this study, we approach that challenge by reducing the substrate temperatures with a homemade Peltier stage and investigate the effects on Pt based 3D deposits in a temperature range of 5–30 °C. The findings reveal a volume growth rate boost up to a factor of 5.6, while the shape fidelity in 3D space is maintained. From a materials point of view, the internal nanogranular composition is practically unaffected down to 10 °C, followed by a slight grain size increase for even lower temperatures. The study is complemented by a comprehensive discussion about the growth mechanism for a more general picture. The combined findings demonstrate that FEBID on low substrate temperatures is not only much faster, but practically free of drawbacks during high fidelity 3D nanofabrication.

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