Results 31 to 40 of about 107,756 (305)

Analytic Model for Low Earth Orbit Satellite Solar Power

IEEE Transactions on Aerospace and Electronic Systems, 2020
An analytic model for calculating the instantaneous and average orbital power available to a satellite in a circular low Earth orbit is presented. By accounting for the effects of angle of solar incidence and eclipsing, for both stabilized and tumbling satellites, this model allows for fast, simple, accurate calculations of available power without the ...
Grey, John Petrus, Mann, Ian R., Fleischauer, Michael D., Elliott, Duncan G.   +3 more
openaire   +1 more source

Utilizing Existing Commercial Geostationary Earth Orbit Fixed Satellite Services for Low Earth Orbit Satellite Communication Relays with Earth [PDF]

New Space, 2019
Abstract There are only a few ways that a low Earth orbit (LEO) satellite can communicate with Earth without a ground station network.
Kopp, Brian, Harris, Jonathan, Lauand, Caio   +2 more
openaire   +2 more sources

Intramolecular Down‐ and Up‐Conversion in Dimeric Tetracene Complexes Centered via Platinum(II) and Palladium(II)

Advanced Functional Materials, EarlyView.
Metal‐tetracene dimeric complexes are synthesized through the pyridyl coordination to either Pt(II) or Pd(II). Photophysical properties are systematically compared as a function of the metal using steady‐state and time‐resolved spectroscopy. The Pt(II) dimer exhibits efficient intramolecular singlet fission and subsequent intramolecular up‐conversion ...
Yifan Bo, Yuxuan Hou, Melchor Matabuena, Rik R. Tykwinski, Dirk M. Guldi   +4 more
wiley   +1 more source

Testing General Relativity and gravitational physics using the LARES satellite

, 2012
The discovery of the accelerating expansion of the Universe, thought to be driven by a mysterious form of `dark energy' constituting most of the Universe, has further revived the interest in testing Einstein's theory of General Relativity.
Ciufolini, Ignazio, Gurzadyan, Vahe, Koenig, Rolf, Matzner, Richard, Paolozzi, Antonio, Pavlis, Erricos, Penrose, Roger, Ries, John, Sindoni, Giampiero   +8 more
core   +1 more source

Cu‐Based MOF/TiO2 Composite Nanomaterials for Photocatalytic Hydrogen Generation and the Role of Copper

Advanced Functional Materials, EarlyView.
HKUST‐1/TiO2 composite materials show a very high photocatalytic hydrogen evolution rate which increases as a function of the irradiation time until reaching a plateau and even surpasses the performance of the 1%Pt/TiO2 material after three photocatalytic cycles.
Alisha Khan, Marie Le Pivert, Alireza Ranjbari, Diana Dragoe, Daniel Bahena‐Uribe, Christophe Colbeau‐Justin, Christian Herrero, Dorota Rutkowska‐Zbik, Johnny Deschamps, Hynd Remita   +9 more
wiley   +1 more source

Atomic Size Misfit for Electrocatalytic Small Molecule Activation

Advanced Functional Materials, EarlyView.
This review explores the application and mechanisms of atomic size misfit in catalysis for small molecule activation, focusing on how structural defects and electronic properties can effectively lower the energy barriers of chemical bonds in molecules like H2O, CO2, and N2.
Ping Hong, Changfan Xu, Huaping Zhao, Yong Lei   +3 more
wiley   +1 more source

Guest Editorial: Low Earth Orbit Satellites to Enable Access Equality [PDF]

, 2022
Güneş Karabulut Kurt, M. A. Vázquez‐Castro, Ejder Baştuǧ   +2 more
openalex   +1 more source

Copper‐based Materials for Photo and Electrocatalytic Process: Advancing Renewable Energy and Environmental Applications

Advanced Functional Materials, EarlyView.
Cu‐based catalysts as a cornerstone in advancing sustainable energy technologies are fully reviewed in this manuscript, highlighting their potential in photo‐ and electrocatalysis. It includes metallic copper, copper oxides, copper sulfides, copper halide perovskites, copper‐based metal–organic frameworks (MOFs), and covalent organic frameworks (COFs),
Jéssica C. de Almeida, Yanjie Wang, Thais A. Rodrigues, Paulo H. H. Nunes, Vagner R. de Mendonça, Paulo H. E. Falsetti, Leticia V. Savazi, Tao He, Alexandra V. Bardakova, Aida V. Rudakova, Jie Tian, Alexei V. Emeline, Osmando F. Lopes, Antonio Otavio T. Patrocínio, Jia Hong Pan, Caue Ribeiro, Detlef W. Bahnemann   +16 more
wiley   +1 more source

Deliberate Satellite Fragmentations and their Effects on the Long-Term Space Environment [PDF]

, 2010
Since 1964 at least 56 spacecraft and two launch vehicle upper stages have been deliberately fragmented while in Earth orbit. Many of these events have had no long-lasting effects on the near-Earth space environment, but one represents the most ...
Johnson, N. L.
core   +1 more source

MnI‐Functionalized Covalent Organic Framework as Efficient Electrocatalyst for CO2 Reduction in a Catholyte‐Free Zero‐Gap Electrolyzer

Advanced Functional Materials, EarlyView.
This work demonstrates the successful integration of a phenanthroline‐based 2D COF with MnI catalytic sites into a catholyte‐free membrane‐electrode‐assembly cell for CO2 electroreduction. The crystalline COF actively suppresses Mn⁰–Mn⁰ dimerization, achieving a turnover frequency of 617 h⁻¹ at 2.8 V (full‐cell potential), and enabling stable operation.
Laura Spies, Marcos Eduardo G. Carmo, Gonçalves J. Marrenjo, Stephan Reuther, Patrick Ganswindt, Antonio Otavio T. Patrocinio, Thomas Bein, Osmando F. Lopes, Jenny Schneider   +8 more
wiley   +1 more source