Results 91 to 100 of about 113,027 (258)

Flight performance of the largest volant bird [PDF]

Proceedings of the National Academy of Sciences, 2014
Significance A fossil species of pelagornithid bird exhibits the largest known avian wingspan. Pelagornithids are an extinct group of birds known for bony tooth-like beak projections, large size, and highly modified wing bones that raise many questions about their ecology.
openaire   +2 more sources

Comparison of Power Requirements: Flapping vs. Fixed Wing Vehicles

Aerospace, 2016
The power required by flapping and fixed wing vehicles in level flight is determined and compared. Based on a new modelling approach, the effects of flapping on the induced drag in flapping wing vehicles are mathematically described.
Gottfried Sachs
doaj   +1 more source

Ultrasmall High‐Entropy Materials: Nanoscale Effects, Synthesis, and Mechanistic Insights

Advanced Functional Materials, EarlyView.
This review article focuses on sub‐10 nm high‐entropy materials that combine nanoscale design with complex compositions for next‐generation applications. ABSTRACT Ultrasmall high‐entropy nanomaterials (USHENMs, <10 nm) merge multicomponent chemistry with size‐dependent effects, forming a distinct class of materials with unprecedented properties.
Yueyue He, Wenbo Wang, Simon Schweidler, Yanjiao Ma, Ben Breitung, Torsten Brezesinski   +5 more
wiley   +1 more source

Reduced Graphene Oxide Transparent Electrodes Enabling Compact Soft Tunable Lenses

Advanced Functional Materials, EarlyView.
By spray‐coating an elastomeric membrane with reduced graphene oxide (rGO) at various surface densities, elastomeric actuators are manufactured. Electro‐mechano‐optical characterizations show the suitability of rGO as an effective material for compliant, semi‐transparent electrodes, enabling soft electrically tunable lenses with a compact form factor ...
Giacomo Sasso, Alec Lamoreux, Nicola Pugno, James J. C. Busfield, Federico Carpi   +4 more
wiley   +1 more source

Calculation Methods of Flight Performance of Flapping Wing Aircrafts Based on Energy Theory and Slipstream Theory (September 2018)

IEEE Access, 2018
Flight performance calculation is an important part of the micro flapping wing air vehicle design. It is used to verify whether the air vehicle design meets the performance requirements so as to make targeted improvements to the design.
Jianlin Xuan, Z. Yang, P. Nian, D. Ma
doaj   +1 more source

Advances in Sustainable and Wearable Textile Based Soft Robotics

Advanced Functional Materials, EarlyView.
This Review examines advances in wearable textile‐based soft robotics, focusing on sustainable materials, integrated sensing, and scalable actuation. It discusses manufacturing and system integration across healthcare, assistive robotics, prosthetics, and human–machine interfaces, and highlights key challenges in circular design, including life‐cycle ...
Zahir Abbas, Marzia Dulal, Sophia K. Novoselov, Victoria K. Novoselov, Kostya S. Novoselov, Shaila Afroj, Nazmul Karim   +6 more
wiley   +1 more source

Low‐Profile, High‐Gain GRIN RF Lenses via Multi‐Material Vat Photopolymerization

Advanced Functional Materials, EarlyView.
We investigate the opportunity of leveraging multi‐material vat photopolymerization printing to manufacture intricate lenses exhibiting permittivity gradients that can increase signal gain in transmitted radiofrequency signals in the X‐ and Ku‐bands. Lenses produced with more distinct low‐loss materials (up to 5) can deliver an 18 dB signal gain with a
Lawrence Romangsuriat, Alexander Peraire‐Bueno, A. John Hart, Randall M. Erb   +3 more
wiley   +1 more source

Interface Effects in Ultrathin Silicon on Insulator Films

Advanced Functional Materials, EarlyView.
This work establishes a systematic framework to discriminate how bulk and interface phenomena affect charge transport in ultrathin P‐doped silicon‐on‐insulator (SOI) films. For Si films below 15 nm, electrical characterization demonstrates that interface states drive charge transport, shifting the metal‐insulator transition (MIT) critical dopant ...
Andrea Pulici, Gabriele Seguini, Fabiana Taglietti, Roman Gumeniuk, Riccardo Chiarcos, Michele Laus, Johannes Heitmann, Marco Fanciulli, Michele Perego   +8 more
wiley   +1 more source

Nano‐Scale Characterization of Impurities Segregation in Solid Oxide Electrolysis Cells

Advanced Functional Materials, EarlyView.
Cathodic polarization induces impurity segregation in Ni, forming an amorphous Na─Al─Si─O amorphous phase at grain boundaries. Under ultralow oxygen partial pressure, multiple elements dissolve, migrate, and reoxidize within the metal. A patterned model system provides direct nanoscale evidence, clarifying the mechanism of polarization‐driven impurity ...
Zhongtao Ma, Qingjie Wang, Bowen Li, Vasileios Bilalis, Søren Bredmose Simonsen, Ming Chen   +5 more
wiley   +1 more source

Circulatory variables and the flight performance of birds [PDF]

Journal of Experimental Biology, 2005
SUMMARYWhen considering the `burst' flight performance of birds, such as during take-off, one of the most important structural variables is the ratio of the mass of the flight muscle myofibrils with respect to body mass. However, when considering `prolonged' flight performance the variable of interest should be the body mass ratio of the mass of the ...
openaire   +2 more sources