Results 161 to 170 of about 346,306 (411)

A preliminary comparison between the SR-3 propeller noise in flight and in a wind tunnel [PDF]

The noise generated by supersonic-tip-speed propellers is addressed. Models of such propellers were tested for acoustics in the Lewis 8-by-6-foot wind tunnel.
Dittmar, J. H., Lasagna, P. L.
core   +1 more source

Elastic suspension of a wind tunnel test section [PDF]

, 1982
Experimental verification of the theory describing arbitrary motions of an airfoil is reported. The experimental apparatus is described. A mechanism was designed to provide two separate degrees of freedom without friction or backlash to mask the small ...
Debra, D. B., Hacker, R., Rock, S.
core   +1 more source

Resolving the Structural Duality of Graphene Grain Boundaries

Advanced Materials, EarlyView.
Cantilever ncAFM resolves the atomic structure of grain boundaries in graphene, revealing coexisting stable and metastable types. Both contain pentagon/heptagon defects, but metastable GBs show irregular geometries. Modeling shows metastable GBs form under compression, exhibiting vertical corrugation, while stable GBs are flat.
Haojie Guo, Emiliano Ventura‐Macías, Mariano D. Jiménez‐Sánchez, Nicoleta Nicoara, Pierre Mallet, Jean‐Yves Veuillen, Vincent T. Renard, Antonio J. Martínez‐Galera, Pablo Pou, Julio Gómez‐Herrero, Rubén Pérez, Iván Brihuega   +11 more
wiley   +1 more source

Calibration of the Langley 16-foot transonic tunnel with test section air removal [PDF]

The Langley 16-foot transonic tunnel with test section air removal (plenum suction) was calibrated to a Mach number of 1.3. The results of the calibration, including the effects of slot shape modifications, test section wall divergence, and water vapor ...
Corson, B. W., Jr., Igoe, W. B., Runckel, J. F.   +2 more
core   +1 more source

Transistor‐Level Activation Functions via Two‐Gate Designs: From Analog Sigmoid and Gaussian Control to Real‐Time Hardware Demonstrations

Advanced Materials, EarlyView.
Screen gate‐based transistors are presented, enabling tunable analog sigmoid and Gaussian activations. The SA‐transistor improves MRI classification accuracy, while the GA‐transistor supports precise Gaussian kernel tuning for forecasting. Both functions are implemented in a single device, offering compact, energy‐efficient analog AI processing ...
Junhyung Cho, Youngmin Han, Won Woo Lee, Youngwoo Yoo, Kannan Udaya Mohanan, Chang‐Hyun Kim, Junhwan Choi, Young‐Joon Kim, Wonjun Shin, Hocheon Yoo   +9 more
wiley   +1 more source

Resonant Interlayer Coupling in NbSe2‐Graphite Epitaxial Moiré Superlattices

Advanced Materials, EarlyView.
Combining angle‐resolved photoemission spectroscopy and density functional theory derived calculations, this work reveals strong interlayer coupling and moiré replicas of the graphite π states in molecular‐beam epitaxy grown van der Waals heterostructures of monolayer‐NbSe2/graphite, with implications for its collective phases that form. Abstract Moiré
Shu Mo, Ksenija Kovalenka, Sebastian Buchberger, Bruno K. Saika, Anugrah Azhar, Akhil Rajan, Andela Zivanovic, Yu‐Chi Yao, Rodion V. Belosludov, Matthew D. Watson, M Saeed Bahramy, Phil D.C. King   +11 more
wiley   +1 more source

Design study of an entry probe spectro-reflectometer [PDF]

A wind tunnel was built to simulate the rapid movement of an entry probe through the Jupiter atmosphere. Wind speeds range from 1 to 50 meters per second in a closed system.
Fink, U., Sill, G. T.
core   +1 more source

A Functional 2D Carbon Allotrope Combining Nanoporous Graphene and Biphenylene Segments

Advanced Materials, EarlyView.
The synthesis of a novel nanoporous graphene (NPG) is reported with biphenylene segments via thermal fusion of 12‐armchair porous graphene nanoribbons grown on gold surfaces. Characterization using STM, AFM, and DFT reveals low‐defect semiconducting behaviour and tunable band gaps.
Paula Angulo‐Portugal, Martin Irizar, Longfeng Huang, Mamun Sarker, Mustafa A. Ashoush, Zakaria M. Abd El‐Fattah, Johannes Barth, Frederik Schiller, Afaf El‐Sayed, Fei Gao, Dimas G. de Oteyza, Alexander Sinitskii, Aran Garcia‐Lekue, Martina Corso, Ignacio Piquero‐Zulaica   +14 more
wiley   +1 more source

Opportunities of Semiconducting Oxide Nanostructures as Advanced Luminescent Materials in Photonics

Advanced Materials, EarlyView.
The review discusses the challenges of wide and ultrawide bandgap semiconducting oxides as a suitable material platform for photonics. They offer great versatility in terms of tuning microstructure, native defects, doping, anisotropy, and micro‐ and nano‐structuring. The review focuses on their light emission, light‐confinement in optical cavities, and
Ana Cremades, Pedro Hidalgo, David Maestre, Ruth Martínez‐Casado, Emilio Nogales, Beatriz Rodríguez, G. Cristian Vásquez, Bianchi Méndez   +7 more
wiley   +1 more source

Asymmetry of the Ferroelectric Phase Transition in BaTiO3

Advanced Materials, EarlyView.
Phase transitions are typically assumed to behave identically in forward and reverse. This work shows that in the ferroelectric material barium titanate this is not true: heating drives an abrupt, first‐order jump, while cooling gives a smooth, continuous change.
Asaf Hershkovitz, Elangovan Hemaprabha, Rajesh Mandal, Pravin Kavle, Jamil Tanus, Maya Barzilay, Ching‐Che Lin, David Spirito, Semën Gorfman, Bo Wang, Ignacio J. Villar‐García, Neus Domingo, Long‐Qing Chen, Lane W. Martin, Yachin Ivry   +14 more
wiley   +1 more source