Results 111 to 120 of about 410,560 (293)

Low-thrust chemical propulsion [PDF]

Results from investigations leading to the definition of low thrust chemical engine concepts are described. From the thrust chamber cooling analyses, regenerative/radiation-cooled LO2/H2 thrust chambers offered the largest thrust and chamber pressure ...
Shoji, J. M.
core   +1 more source

Unprecedented Spin‐Lifetime of Itinerant Electrons in Natural Graphite Crystals

Advanced Functional Materials, EarlyView.
Graphite exhibits extraordinary spintronic potential, with electron spin lifetimes reaching 1,000 ns at room temperature ‐ over 100 times longer than graphene‐based devices. Magnetic resonance spectroscopy reveals strong anisotropy: out‐of‐plane spins live 50 times longer than their in‐plane counterparts.
Bence G. Márkus, Dávid Beke, Lili Vajtai, András Jánossy, László Forró, Ferenc Simon   +5 more
wiley   +1 more source

Grain Boundary Space Charge Engineering of Solid Oxide Electrolytes: Model Thin Film Study

Advanced Functional Materials, EarlyView.
This study demonstrates unprecedented control of grain boundary electrical properties in solid electrolytes. Selective diffusion of cations through grain boundaries in thin films enables 12 orders of magnitude variation in ionic resistance, proving that systematic chemical modification of grain boundary electrical properties is feasible.
Thomas Defferriere, Yong Beom Kim, Colin Gilgenbach, James M. LeBeau, WooChul Jung, Harry L. Tuller   +5 more
wiley   +1 more source

Trailing-Edge Beveling Effect on Passive Fluidic Thrust Vectoring Nozzle Jet Deflection Control

Aerospace
Passive fluidic thrust vectoring nozzles feature a simple structure and low energy consumption. However, traditional 2D passive fluidic thrust vectoring nozzle suffers from jump and control reversal in thrust angle.
Zi Huang, Yunsong Gu, Linkai Li, Zemin Wu, Yuhang Zhou, Shuai Deng   +5 more
doaj   +1 more source

Hydrogen/oxygen auxiliary propulsion technology [PDF]

A survey is provided of hydrogen/oxygen (H/O) auxiliary propulsion system (APS) concepts and low thrust H/O rocket technology. A review of H/O APS studies performed for the Space Shuttle, Space Tug, Space Station Freedom, and Advanced Manned Launch ...
Reed, Brian D., Schneider, Steven J.
core   +1 more source

Semi-analytical guidance algorithm for autonomous close approach to non-cooperative low-gravity targets [PDF]

, 2014
An adaptive guidance algorithm for close approach to and precision landing on uncooperative low-gravity objects (e.g. asteroids) is proposed. The trajectory, updated by means of a minimum fuel optimal control problem solving, is expressed in a polynomial
Armellin, Roberto, Lunghi, Paolo, Michele, Lavagna   +2 more
core  

Charge‐Induced Morphing Gels for Bioinspired Actuation

Advanced Functional Materials, EarlyView.
This study introduces a novel electroactive actuation mechanism that enables the gel material to generate substantial and reversible shape‐changing while preserving topological and isochoric (volumetric) equivalence. The resultant morphing behaviors can mimic the movements of muscle‐driven organelles in nature, including cilia‐like beating and ...
Ciqun Xu, Saba Firouznia, Charl F. J. Faul, Majid Taghavi, Jonathan Rossiter   +4 more
wiley   +1 more source

Three dimensional thrust chamber life prediction [PDF]

A study was performed to analytically determine the cyclic thermomechanical behavior and fatigue life of three configurations of a Plug Nozzle Thrust Chamber. This thrust chamber is a test model which represents the current trend in nozzle design calling
Armstrong, W. H., Brogren, E. W.
core   +1 more source

Multi‐Ion Doping Controlled CEI Formation in Structurally‐Stable High‐Energy Monoclinic‐Phase NASICON Cathodes for Sodium‐Ion Batteries

Advanced Functional Materials, EarlyView.
The graphical abstract illustrates the synthesis pathway, morphological feature, and thermodynamic feasibility of entropy‐engineered NASICON cathodes for sodium‐ion batteries. Abstract Overcoming the energy density limitations of sodium‐ion batteries (NIBs) requires innovative strategies to optimize cathode materials.
Sharad Dnyanu Pinjari, Vignesh Mahalingam, Purandas Mudavath, Malavika Aarayil, Tasdique Arman, Ipsita Pal, Dipan Kundu, Raghavan Ranganathan, Ashok Kumar Nanjundan, Rohit Ranganathan Gaddam   +9 more
wiley   +1 more source

Unveiling Aggregation‐Induced Singlet Fission in Push–Pull Diketopyrrolopyrrole Water Dispersed Nanoaggregates and Thin Films

Advanced Functional Materials, EarlyView.
Aggregates of diketopyrrolopyrrole dipolar and quadrupolar systems exhibit panchromatic absorption spectra extending in the entire visible range. Upon aggregation in water and in the solid state, their fluorescence is almost completely quenched and their singlet excited state lifetime is significantly shortened.
Roberto Cantoni, Martina Alebardi, Eliana Maria D'Amato, Charu Popli, Yuvraj Patil, Pietro Mancini, Alessandro Di Michele, Anna Spalletti, Rajneesh Misra, Theodore Goodson, Benedetta Carlotti   +10 more
wiley   +1 more source