The MESSENGER spacecraft began detecting energetic electrons with energies greater than 30 kilo-electron volts (keV) shortly after its insertion into orbit about Mercury. In contrast, no energetic protons were observed. The energetic electrons arrive as bursts lasting from seconds to hours and are most intense close to the planet, distributed in latitude from the equator to the north pole, and present at most local times. Energies can exceed 200 keV but often exhibit cutoffs near 100 keV. Angular distributions of the electrons about the magnetic field suggest that they do not execute complete drift paths around the planet. This set of characteristics demonstrates that Mercury's weak magnetic field does not support Van Allen-type radiation belts, unlike all other planets in the solar system with internal magnetic fields.
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http://dx.doi.org/10.1126/science.1211141 | DOI Listing |
Chem Asian J
December 2024
IOCB CAS: Ustav organicke chemie a biochemie Akademie ved Ceske republiky, Chemistry, 16000, CZECHIA.
Single-atom-based Metal-Organic Frameworks (MOFs) hold great promising candidates for heterogeneous catalysis, demonstrating outstanding catalytic activity and exceptional product selectivity. This is attributed to their optimal atom utilization, high surface energy, and the presence of unsaturated coordination environments. Here in, we have developed a nickel single-atom catalyst (UiO-66/Ni) featuring Ni single atoms covalently attached to defect-engineered Zr-oxide clusters within the stable UiO-66 framework, synthesized via a straightforward solution impregnation method.
View Article and Find Full Text PDFJ Chem Phys
December 2024
Max Planck Institute for the Structure and Dynamics of Matter and Center for Free-Electron Laser Science, Luruper Chaussee 149, 22761 Hamburg, Germany.
In this work, we theoretically explore whether a parity-violating/chiral light-matter interaction is required to capture all relevant aspects of chiral polaritonics or if a parity-conserving/achiral theory is sufficient (e.g., long-wavelength/dipole approximation).
View Article and Find Full Text PDFCell Mol Biol (Noisy-le-grand)
November 2024
Department of Plant Sciences and Biotechnology, Faculty of Life Sciences and Biotechnology, Shahid Beheshti University, Tehran, Iran.
The present study aimed to investigate the impact of progressive drought stress (100%, 75%, 50%, and 25% of field capacity) on photosynthetic light reactions of tomato plants. The imposed drought caused a gradual reduction in leaf RWC leading to a decline in pigment concentration and growth indices. Significant alteration in the OJIP fluorescence transient curves and the formation of specific fluorescence bands (L, K, J, H, and G) gradually increased as drought severity increased.
View Article and Find Full Text PDFWater Res
December 2024
School of Resources and Environmental Engineering, Hefei University of Technology, Hefei, Anhui 230009, China; Anhui Engineering Research Center of Industrial Wastewater Treatment and Resource Recovery, Hefei University of Technology, Hefei, Anhui 230009, China; Key Laboratory of Nanominerals and Pollution Control of Anhui Higher Education Institutes, Hefei University of Technology, Hefei, Anhui 230009, China. Electronic address:
Microalgae are recognized for their potential in the bioremediation of acid mine drainage (AMD), despite the challenges posed by AMD's low pH, high heavy metal content, and oligotrophic conditions. However, the impact of AMD chemoautotrophic microorganisms on microalgal growth and remediation efforts within AMD has been largely overlooked. This study aims to elucidate the effects the chemoautotrophic microorganism, Acidithiobacillus ferrooxidans, on the growth activity and metabolism of acid-tolerant microalgae, and to explore the molecular mechanisms of microalgal response.
View Article and Find Full Text PDFChemistryOpen
December 2024
Institut für Chemie, Anorganische Chemie, Universität Potsdam, Karl-Liebknecht-Str. 24-25, 14476, Golm, Germany.
In this paper, we report on the sensing role of the 1,2,3-triazol unit in a 1,4-diyl arrangement in a fully π-conjugated fluorescent probe 1 (cf. Scheme 1) towards the fluorometric detection of 3d metal ions. The 1,2,3-triazol-1,4-diyl-fluoroionophore 1 was designed in a donor(D)-acceptor(A) arrangement with a 1,2,3-triazol unit as a π-linker between a terpyridine (A) ionophore and a diethylaminocoumarin (D) fluorophore to study the fluorescence behavior towards the divalent 3d metal ions Mn, Fe, Co, Ni, Cu and Zn.
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