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Photobromination of toluene derivatives using blue LED (454 nm) or UV LEDs (365, 385, 395 nm) with aqueous HBr and NaOCl·5H2O in trifluoromethyl benzene afforded the corresponding benzoic acids derivatives. The intermediates were (dibromomethyl)benzene derivatives, isolated in a nitrogen atmosphere. The dibromomethyl benzene derivatives afforded the corresponding aldehydes. After the reaction with HBr, the aqueous layer could be recovered and reused. [ABSTRACT FROM AUTHOR]

Autoxidation of aldehydes to peracids and carboxylic acids holds a significant impact in both academia and industry due to their wide applications in organic synthesis and environmental remediation. However, the multiple pathways involved in this reaction have hindered the development of sustainable methods for peracid synthesis. Herein, we conduct a comprehensive kinetic and mechanistic investigation to elucidate the interplay between these pathways. Subsequently, we introduce an efficient eco-friendly method to oxidize aldehydes to their corresponding peracids under sunlight or UV irradiation using oxygen as the sole oxidant without any additives or photocatalysts. Additionally, we demonstrate a simple method for the autoxidation of aldehydes to carboxylic acids via controlling key parameters such as the wavelength and solvent. These methods exhibit broad applicability to aromatic and aliphatic aldehydes, successful scaling up to the gram scale, and utilizing renewable solar energy making them good alternatives for traditional methods. [ABSTRACT FROM AUTHOR]

E.J. Axton’s experimental database adopted in evaluation of thermal neutron constants by himself and also by a recent project to update the IAEA Neutron Standard was checked against the experimental literature and EXFOR library. We discovered that many data are found neither in the EXFOR library nor in the articles quoted by Axton due to various reasons. This paper summarizes the status of the experimental data cited by Axton in the experimental literature as well as in the EXFOR library.

The fabrication of a current doubler device by capacitively coupling two short arrays of 20 mesoscopic Josephson junctions with a long array of 40 junctions is described.

Phosphatidylcholine- and phosphatidylethanolamine-specific phospholipase C (PC-PLC and PE-PLC) activities, which generate diacylglycerol (DG) and are tricyclodecan-9-yl-xanthogenate (D609)-sensitive, have been detected in both the membrane and cytosolic fractions. We have previously demonstrated that sphingomyelin synthase isozymes, which are transmembrane proteins, exhibit PC-/PE-PLC activities. However, mammalian cytosolic PC-PLC and PE-PLC remain unidentified. Here, we demonstrated that phosphatase orphan 1 (PHOSPHO1), a cytosolic protein, exhibits D609-sensitive PC-PLC and PE-PLC activities. Moreover, the overexpression of PHOSPHO1 in HEK293 cells significantly increased the levels of cellular saturated and/or monounsaturated fatty acid-containing DG. Furthermore, DGKδ cosedimented and colocalized with PHOSPHO1. Collectively, these in vitro findings provide, for the first time, a promising candidate for the long-sought cytosolic PC-/PE-PLC, which may act as DG supply enzyme upstream of DGKδ., (© 2025 Federation of European Biochemical Societies.)

The hydrostatic pressure dependent evolution of the electronic and magnetic structure of LaCo 5 and YCo 5 was investigated by means of x-ray emission spectroscopy, x-ray diffraction, and spin-polarized density functional theory (DFT) calculations. Using experimental lattice parameters the DFT correctly predicts the pressure of the magnetic transition in both compounds to be 26 GPa (La) and 22-23 GPa (Y). The transition was experimentally resolved in the changes of the electronic structure via the integrated absolute difference of the Co Kβ emission spectra. Comparison of theory and experiment confirm for the first time a common feature in both LaCo 5 and YCo 5 to be the source of the transition; the Fermi-level crossing of an up-spin polarized flat band driving the systems into a low spin configuration via a Lifshitz type transition of the Fermi surface. Another phase transition observed around 12 GPa in LaCo 5 was clarified to be caused by the change in the down-spin density of states at the Fermi level., (© 2022 IOP Publishing Ltd.)

A carrier doping by a hydrogen substitution in LaFeAsO 1- x H x is known to cause two superconducting (SC) domes with the magnetic order at both end sides of the doping. In contrast, SmFeAsO 1- x H x has a similar phase diagram but shows single SC dome. Here, we investigated the electronic and crystal structures for iron oxynitride Ln FeAsO 1- x H x ( Ln = La, Sm) with the range of x = 0-0.5 by using x-ray absorption spectroscopy, x-ray emission spectroscopy, and x-ray diffraction. For both compounds, we observed that the pre-edge peaks of x-ray absorption spectra near the Fe- K edge were reduced in intensity on doping. The character arises from the weaker As-Fe hybridization with the longer As-Fe distance in the higher doped region. We can reproduce the spectra near the Fe- K edge according to the Anderson impurity model with realistic valence structures using the local-density approximation (LDA) plus dynamical mean-field theory (DMFT). For Ln = Sm, the integrated-absolute difference (IAD) analysis from x-ray Fe- Kβ emission spectra increases significantly. This is attributed to the enhancement of magnetic moment of Fe 3 d electrons stemming from the localized picture in the higher doped region. A theoretical simulation implementing the self-consistent vertex-correction method reveals that the single dome superconducting phase for Ln = Sm arises from a better nesting condition in comparison with Ln = La., (© 2021 IOP Publishing Ltd.)

We examine electronic and crystal structures of iron-based superconductors Ln FeAsO 1- x H x ( Ln = La, Sm) under pressure by means of x-ray absorption spectroscopy (XAS), x-ray emission spectroscopy (XES), and x-ray diffraction. In LaFeAsO the pre-edge peak on high-resolution XAS at the Fe- K absorption edge gains in intensity on the application of pressure up to 5.7 GPa and it saturates in the higher pressure region. We found integrated-absolute difference values on XES for Ln = La, corresponding to a spin state, decline on the application of pressure, and then it is minimized when the T c approaches the maximum at around 5 GPa. In contrast, such the optimum value was not detected for Ln = Sm. We reveal that the superconductivity is closely related to the lower spin state for Ln = La unlike Sm case. We observed that As height from the Fe basal plane and As-Fe-As angle on the FeAs 4 tetrahedron for Ln = La deviate from the optimum values of the regular tetrahedron in superconducting (SC) phase, which has been widely accepted structural guide to SC thus far. In contrast, the structural parameters were held near the optimum values up to ∼15 GPa for Ln = Sm., (© 2021 IOP Publishing Ltd.)