Results 1 to 10 of about 56,835 (159)

Flip Angle Errors in Actual Flip Angle Imaging Using Polyvinylpyrrolidone/Water-Based Phantoms. [PDF]

Magn Reson Med
ABSTRACT Purpose The aim of this work is to report and investigate unexpected errors in actual flip angle imaging (AFI) applied to phantom fillings based on polyvinylpyrrolidone (PVP). Methods Flip angle maps of PVP/water mixtures with different PVP ratios were acquired at 3 T and 7 T using a 3D cartesian AFI. The influence of spoiling was investigated
Himburg N, Lutz M, Mitschang L, Frintz JG, Schmitter S.   +4 more
europepmc   +2 more sources

N-Heterocyclic Carbenes on a III-V Semiconductor: From Chain Formation to Ordered Monolayers. [PDF]

Angew Chem Int Ed Engl
The functionalization of GaAs, a model III‐V semiconductor, with N‐heterocyclic carbenes is demonstrated in a multidisciplinary experimental and theoretical approach. In this way, ordered monolayers consisting of chains of molecules binding covalently to the surface are obtained, which are found to strongly modify the surface properties as evident from
Franz M, Das A, Chandola S, Kubicki M, Das M, Sette A, Corona D, Palummo M, Chiodo L, Schöder R, Chahar P, Fuhrmann B, Engelhardt J, Düren O, Rosenzweig DS, Bakos P, Jakob KL, Dähne M, Hogan C, Esser N, Glorius F.   +20 more
europepmc   +2 more sources

Capacitive photocharging of gold nanorods [PDF]

Nature Communications
Light can charge plasmonic nanoparticles by photoredox reactions, significantly modifying their optical and chemical properties. However, the charging process has been challenging to track experimentally, severely hindering its thorough evaluation.
Felix Stete, Matias Bargheer, Wouter Koopman   +2 more
doaj   +2 more sources

Is Phenylnitrene a Missing Link in the Formation of Polycyclic Aromatic Nitrogen Heterocycles? [PDF]

Angew Chem Int Ed Engl
A new formation pathway for polycyclic aromatic nitrogen heterocycles (PANHs) has been found. The reaction of phenylnitrene and the propargyl radical leads to quinoline, proving that nitrenes are suitable precursors for nitrogen incorporation mechanisms.
Arns R, McClish R, Hemberger P, Bodi A, Bouwman J, Kasper T, Schleier D.   +6 more
europepmc   +2 more sources

A multiscale <i>in situ</i> time-resolved study of the nano- to millisecond structural dynamics during protein crystallization. [PDF]

J Appl Crystallogr
Protein crystallization is a crucial method for structure determination and biological studies, but its pathways remain poorly understood, often relying on trial and error to initiate crystallization. Using a multitechnique approach, this study investigates structural and diffusion properties across various time and length scales to compare different ...
Beck C, Mosca I, Miñarro LM, Sohmen B, Buchholz C, Maier R, Reichart LF, Grundel AC, Bäuerle F, Nasro R, Banks H, Christmann S, Pastryk KF, Farago B, Czakkel O, Prévost S, Gerlach A, Grimaldo M, Roosen-Runge F, Matsarskaia O, Schreiber F, Seydel T.   +21 more
europepmc   +2 more sources

Inverted temperature gradients in gold–palladium antenna-reactor nanoparticles [PDF]

Nature Communications
In addition to enhanced fields and possible charge transfer, the concentration of photothermal energy at the nanoscale is a central feature of plasmon-driven photochemistry.
Felix Stete, Shivani Kesarwani, Charlotte Ruhmlieb, Sven H. C. Askes, Florian Schulz, Matias Bargheer, Holger Lange   +6 more
doaj   +2 more sources

Mitigating Mobile-Ion-Induced Instabilities and Performance Losses in 2D Passivated Perovskite Solar Cells. [PDF]

Adv Mater
This study addresses the challenges of mobile‐ion‐induced instability in perovskite solar cells. Introducing bilayer passivation with ammonium salts (EDAI₂/PEAI and ABS/PEAI) significantly reduces ion density and improves device stability. The approach mitigates the detrimental effects of PEAI‐induced ionic losses, enhancing both performance and ...
Seid BA, Ozen S, Castro-Méndez AF, Neher D, Stolterfoht M, Lang F.   +5 more
europepmc   +2 more sources

Eduard Heis, an early pioneer in meteor research [PDF]

History of Geo- and Space Sciences, 2021
At the beginning of the 19th century, meteor observations were not well established. One of its pioneers, who observed meteors on a regular basis, was Eduard Heis in Münster, Germany. We summarise the life of this scientist.
U. Sperberg
doaj   +1 more source

Les tables de réfraction astronomique

Comptes Rendus. Physique, 2023
The paper investigates the refraction as it concerns position astronomy and the attempts of generations of astronomers since Tycho Brahe to estimate its size as a function of the apparent zenith distance of the sources.
Mignard, François
doaj   +1 more source

L’enfant merveilleux chez Héraclite d’Ephèse

Archai: Revista de Estudos sobre as Origens do Pensamento Ocidental, 2020
Dans la phrase marquée DK22 B52, Héraclite décrit un enfant jouant avec de petits objets (pessoi). Le garçon a tout un royaume à sa disposition et il est identifié lui-même avec l’éon.
Małgorzata Kwietniewska
doaj   +1 more source