Results 41 to 50 of about 12,334 (255)
Chemical Maturation Controls Bioavailability of Fetuin‐A‐Mineral Complexes in Biomineralization
Advanced Functional Materials, EarlyView.The role of Fetuin‐A‐mineral complexes in matrix mineralization is unclear. Here, Fetuin‐A‐mineral complexes were found to exist in functionally distinct states that determine mineral bioavailability: chemically labile calciprotein monomers directly mineralize collagen fibrils, while chemically matured primary calciprotein particles require cellular ...
Judith M. Schaart +8 more
wiley +1 more source
Influence of Rotor Dynamic Scattering on Helicopter Radar Cross-Section
Sensors, 2020 With the continuous improvement and development of armed helicopters, the research on their stealth characteristics has become more and more in depth. In order to obtain the complex effect of stealth characteristics caused by the high-speed rotation of ...
Zeyang Zhou, Jun Huang
doaj +1 more source
Sensitivity of tail rotor noise to helicopter configuration in forward flight [PDF]
, 2009 Understanding the mechanisms that lead to the production of noise by tail rotors across a broad range of flight conditions and helicopter configurations remains an active area of research.
Fletcher, Timothy M. +5 more
core
In Situ Amine Formation to Modulate MOF‐Derived PdIn N‐Doped Carbon Catalysts
Advanced Materials, EarlyView.An amine‐assisted approach converts PdIn‐MOF into PdIn intermetallic nanoparticles embedded in N‐doped carbon. In situ‐generated amines trigger early Pd nucleation, producing smaller PdIn domains than direct pyrolysis. Amine sterics and basicity tune composition and particle size, while solvent and amine co‐determine textural features.
Gonzalo Egea +9 more
wiley +1 more source
Some Peculiarities of Helicopter Main Rotor Aeroacoustic for Far-Field Observer [PDF]
EPJ Web of Conferences, 2019 Mathematical models for helicopter rotor acoustics are usually based on the Ffowcs Williams–Hawkings (FW–H) equation. The level of rotor noise is determined by geometry (thickness noise) of a flying vehicle and distributed blade loading (loading noise ...
Kusyumov Alexander +4 more
doaj +1 more source
Numerical Study of Coaxial Main Rotor Aerodynamics in Steep Descent
Aerospace, 2022 Numerical studies of the aerodynamic characteristics of the coaxial main rotor of the Kamov Ka-32 helicopter in steep descent modes, including the area of the vortex ring state (VRS) modes, have been performed.
Pavel Makeev +2 more
doaj +1 more source
Aeroacoustic analysis of main rotor-tail rotor interaction [PDF]
, 2008 The increased restrictions placed on helicopter noise levels over recent decades have encouraged manufacturers to better understand tail rotor noise and its aerodynamic sources. A generic single main rotor and tail rotor helicopter has been simulated in high speed forward, and quartering, flight using the Vorticity Transport Model.
Fletcher, Timothy M. +2 more
openaire +1 more source
Development of an Active Flap Rotor Model [PDF]
, 2004 The research organizations ONERA and DLR initiated a common programme supported by Eurocopter (EC) and Eurocopter Deutschland (ECD) as industry partners within the Active Blade Concept (ABC).
Höfinger, Marc T., Leconte, Philippe
core
Nonlocal Metaspire: A Scalable Elastic Material Platform With Decoupled Mechanical Modes
Advanced Materials, EarlyView.Nonlocal Metaspire introduces sequential rotation to realize wider scalability in implementing complex nonlocal couplings in elastic metamaterials while suppressing unintended mode coupling. Numerical results clarify the underlying wave motions, demonstrate mode‐decoupled roton and maxon formation, and support a straightforward extension to higher ...
Seung Han Kim +3 more
wiley +1 more source
Nihon Kikai Gakkai ronbunshu, 2020 The flow and performance of a rotor of a Savonius hydraulic turbine provided with a shield plate were analyzed by the two-dimensional simulations. The rotor diameter DR is 142 mm, and the Reynolds number based on the velocity of the main flow U0, U0DR/ν,
Kotaro TAKAMURE +5 more
doaj +1 more source