Results 101 to 110 of about 6,561 (302)

Resolving the Cu(bdc) Conundrum: Identifying Non‐Porous Packing of Prototypical Coordination‐Network Thin Films Combining Advanced Diffraction Techniques and Computational Modelling

open access: yesAdvanced Functional Materials, EarlyView.
Solution‐processed Cu(bdc) forms prototypical MOF thin films for which a multitude of not fully satisfactory structural models have been suggested. Combining rotating grazing‐incidence diffraction and X‐ray reflectivity on two complementary samples with density‐functional theory, we first discard the previously suggested models and then identify a non ...
Narges Taghizade   +7 more
wiley   +1 more source

Long‐Range Coordination Environment Modulates Single‐Atom Local States and Systemic Impact on CO2 Photoconversion

open access: yesAdvanced Functional Materials, EarlyView.
Terminal groups on Cu porphyrins modulate the electronic states of single‐atom Cu centers through a long‐range electronic effect, without altering the Cu coordination geometry. Meanwhile, a multi‐descriptor framework is established that incorporates porphyrin regulation, hybrid catalyst properties, and CO2 photoreduction capabilities.
Yi Zhang   +13 more
wiley   +1 more source

A selfl-adaptive magnetic charged system for time-suboptimal formation flying maneuvers

open access: yes, 2019
The development of fast and reliable optimization algorithms is required in order to obtain real-time optimal trajectory on-board spacecraft. In addition, the wide spread of small satellites, due to their low costs, is leading to a greater number of ...
Dario Spiller   +2 more
core  

Challenges to Space Activities in the Context of Mega Satellite Constellations: A Focus on Environmental Impacts

open access: yesJournal of Astronomy and Space Sciences
The advent of low Earth orbit (LEO) mega satellite constellations to accelerate high-speed internet worldwide represents a new technological advancement.
Sheer
doaj   +1 more source

Tailoring Li‐ion Storage and Transport in Two‐Dimensional Conjugated Metal‐Organic Frameworks via Precise Nitrogen Incorporation

open access: yesAdvanced Functional Materials, EarlyView.
Two nitrogen‐doped 2D conjugated metal‐organic frameworks (2D c‐MOFs, namely Cu‐Nx‐OHBA, x = 2 or 4) are synthesized, featuring precise nitrogen incorporation via rational ligand design. The Cu‐Nx‐OHBA 2D c‐MOFs are largely tailorable by varying skeletal nitrogen density, with respect to electrical conductivity, Li‐storage capacitance, and Li‐transport
Xiangyu Li   +7 more
wiley   +1 more source

Unraveling the Electronic Structure of Silicon Vacancy Centers in 4H‐SiC

open access: yesAdvanced Functional Materials, EarlyView.
The electronic structure of the silicon vacancy in 4H‐SiC is probed via transient absorption spectroscopy, uncovering previously inaccessible excited states of the quartet and doublet spin channels, including the V2' transition. In combination with theoretical analysis, a comprehensive picture of the electronic structure is established.
Ali Tayefeh Younesi   +9 more
wiley   +1 more source

Designed Lewis Acid–Base Passivation for High Performance Perovskite Solar Cells

open access: yesAdvanced Functional Materials, EarlyView.
ABSTRACT Silicon's high cost and long energy payback time remain major barriers to the global expansion of solar power. In contrast, metal–halide perovskites offer abundant, solution‐processable absorbers, and have achieved efficiencies of 25%–30%, positioning them as strong competitors to silicon.
Afna Manaf   +4 more
wiley   +1 more source

Integrating LEO Satellite Constellations into Internet Backbone

open access: yes, 2007
Low Earth Orbit (LEO) satellite constellations have been used for ubiquitous and flexible Internet access services. However, a number of problems related to the integration of terrestrial with satellite hosts should be resolved for the effective ...
He, Yan
core  

Mercator Projection Superposition: A Computationally Efficient Alternative to Grid-Based Coverage Analysis for LEO Mega-Constellations

open access: yesApplied Sciences
Grid point approaches for LEO mega-constellation coverage analysis become computationally prohibitive for constellations exceeding 103 satellites due to exponential complexity growth.
Guanhua Feng, Linli Lv, Wenhao Li
doaj   +1 more source

A Study on Global Satellite Constellation for Satellite Navigation.

open access: yesJournal of the Japan Society for Aeronautical and Space Sciences, 1994
This paper discusses several types of global satellite constellations applied for the integrated satellite mission which accomplishes radio navigation, mobile communication and earth observation globally, and mainly considers position determination (navigation) accuracy achieved by these constellations.
openaire   +2 more sources

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