Publications by authors named "Hans Agren"

Simultaneous organic pollutant oxidation and heavy metal ion reduction may enhance ocean and medical wastewater treatment. Here a self-cycling piezo-photocatalytic Fenton (SPF) system was developed using an Na-Sm bimetal-doped layered ferroelectric perovskite SrBiNbO (NS-SBNO) and Fe ions. The experimental results and density functional theory calculations demonstrated that bimetal doping induced an enhanced internal electric field, improving electron-hole pair separation and transmission.

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Dissociation upon sulfur K-shell excitation or ionization of SF_{6} is studied by sulfur L-shell emission spectroscopy using synchrotron radiation and multiconfiguration Dirac-Hartree-Fock calculations of emission energies and transition rates. The decay path involves in particular Auger emission with the ejection of one or more electrons, leading to singly or multiply charged intermediate states. Nevertheless, the results of the study show that the observed photon emission at 151-152 eV following excitation at 2485-2489 eV originates dominantly from transitions in neutral sulfur.

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Nitrogen substitutions have shown a great impact for the development of thermally activated delayed fluorescence (TADF)-based organic light-emitting diode (OLED) materials. In particular, much focus has been devoted to nitrogen-substituted polycyclic aromatic hydrocarbons (PAHs) for TADF emitters. In this context, we provide here a molecular design approach for symmetric nitrogen substitutions in fused benzene ring PAHs based on the dibenzo[,]picene (DBP) molecule.

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The oxidative degradation of plastics in conjunction with the production of clean hydrogen (H) represents a significant challenge. Herein, a NiS/ZnCdS heterojunction is rationally synthesized and employed for the efficient production of H and high-selectivity value-added chemicals from waste plastic. By integrating spectroscopic analysis techniques with density functional theory (DFT) calculations, a solely electron transfer-mediated reaction mechanism is confirmed, wherein NiS extracts electrons from ZnCdS (ZCS) to promote the spatial segregation of photogenerated electrons and holes, which not only facilitates H production but also maintains the high oxidation potential of holes on the ZCS surface, favoring hole-dominated plastic oxidation.

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Organic hole-transporting materials (HTMs) with high hole mobility and a defect passivating ability are critical for improving the performance and stability of perovskite optoelectronics, including perovskite quantum dot light-emitting diodes (Pe-QLEDs) and perovskite solar cells. In this study, we designed two small-molecule HTMs, termed and , incorporating the methylthio group (SMe) as defect-passivating sites to enhance the interaction between HTMs and the perovskite layer for Pe-QLED applications. Our study highlights that , featuring SMe groups at the para-position of the carbazole unit, demonstrates a strong interaction and superior passivation effects with perovskite quantum dots.

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The size of the lanthanide upconversion nanocrystals significantly impacts their luminescence properties, yet the underlying mechanisms remain unclear. In this work, we undertake a systematic examination of the size effects in the commonly studied hexagonal phase sodium yttrium fluoride (β-NaYF) nanocrystals codoped with ytterbium and erbium ions and their core-shell structure. We demonstrate the coexistence of surface quenching and finite-size-dependent energy transfer mechanisms, quantify the effects of size-dependent surface quenching and finite-size-dependent energy transfer, and determine an interaction energy transfer distance limit of ∼8.

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We introduce a donors-acceptor-based molecular design strategy of organic heteroaromatic compounds with enhanced photosensitivity in the ultraviolet (UV)/visible/near-infrared (NIR) regions. Three organic dyes are meticulously designed and synthesized, involving various donor (D) moieties and the anthraquinone acceptor (A) unit, following the so-called quasi-orthogonal A-D-D' architecture. The target compounds are synthesized via the Buchwald-Hartwig cross-coupling reactions, with the yields of up to 54 %.

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Oxidative dimerization of π-conjugated molecules is a straightforward approach for effectively extending π-conjugation and absorption features. However, it is challenging to construct dimeric species of bulky π-conjugated frameworks because of the steric hindrances and/or poor regioselectivity. To address these issues, a pyrrole unit has been regioselectively appended to the α position of N-confused hexaphyrin (1.

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It is always important and fascinating to explore new organic emitters that exploit unconventional pathways to unveil their emission with unique properties, such as thermally activated delayed fluorescence (TADF). In this study, we report that the rarely explored sulfur lone pair (n) is a promising alternative, where the correlated π* → n emission can be used to attain strong TADF and thus practical OLEDs. The designed strategy incorporates several key concepts (Figure 1a), in which the persulfide aromatic spirocycle enhances spin-orbit coupling, thereby increasing the intersystem crossing rate.

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Oxidation of thia-pentapyrrane S-P4 with terminal β-linked pyrrole and thiophene units in the presence of various metal ions has been found to afford distinct porphyrinoids. Specifically, N-confused thiasapphyrin (1), Cu(III) norrole (2), neo-confused phlorin (3), and p-benzinorrole (4) were obtained, when S-P4 was oxidized with p-chloranil in acetonitrile in the presence of Ni, Cu, Cd, and Co, respectively. The structures of 1-4 have been clearly elucidated by NMR spectroscopy, HRMS, and X-ray crystal diffraction (for 2-4).

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The line list is essential for accurately modeling various astrophysical phenomena, such as stellar photospheres and atmospheres of extrasolar planets. This paper introduces a new line database for the PS molecule spanning from the ultraviolet to the infrared regions, covering wavenumbers up to 45000 cm and containing over ten million transitions between 150,458 states with total angular momentum J < 160. Accurate line intensities for rotational, vibrational and electronic transitions are generated by using the general purpose variational code DUO.

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This study investigates the equilibrium geometries of four different Se isomers using the coupled cluster single and double perturbative (CCSD(T)) method, extrapolating to the complete basis sets. The ground-state geometry of the Se isomer with the C structure (2.8715 Å, 2.

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Developing new organic radical emission systems and regulating their luminescence properties presents a significant challenge. Herein, we build dynamic and multi-emission band radical luminescence systems by co-assembling inorganic metal salts with carbonyl compounds in ionic liquids. After the assembling, dual-band, and excitation wavelength-dependent emission was observed upon ultraviolet light irradiation, one emission band originates from carbonyl radical after light irradiation, the other band from the ligand-metal charge transfer (LMCT) state, which benefits from the charge transfer from the radicals to the metal salts.

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Background: Clinical characteristics of psychosis in HIV infection have been described, but there have been limited comparative studies in HIV-endemic low-resource regions.

Aim: To compare clinical characteristics of psychosis in HIV-positive and HIV-negative patients at the main psychiatric referral units in Uganda.

Method: Patients with psychosis were consecutively recruited and completed a standardised demographic questionnaire and psychiatric and laboratory assessments including an HIV test.

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Although photochromic molecules have attracted widespread interest in various fields, solid-state photochromism remains a formidable challenge, owing to the substantial conformational constraints that hinder traditional molecular photoisomerization processes. Benefiting from the significant color change upon radical generation, chemical systems enabling a photoinduced radical (PIR) behavior through photoinduced electron transfer (PET) could be ideal candidates for solid-state photochromism within minimized need of conformational freedom. However, the transient nature of radicals causes a dilemma in this Scheme.

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Two-dimensional (2D) chromium(III) sulfide has recently attracted increased attention from researchers due to its interesting electronic and magnetic properties and has great potential for application in spintronics and optoelectronics to create sensitive photodetectors. However, the synthesis of 2D CrS crystals is still a challenging task. At present, the mainly used method is vapor deposition, which is a poorly scalable, time-consuming, and expensive process.

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The N-confused [14]triphyrin(2.1.1) was facilely synthesized and readily converted into N-confused triphyrinone(2.

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Plasmonics serves as a most outstanding feature of nanoparticle technology and is nowadays used in numerous applications within imaging, sensing and energy harvesting, like plasmonically enhanced solar cells, nanoparticle bioimaging, plasmon-controlled fluorescence for molecular tracking in living cells, plasmon-controlled electronic molecular devices and surface enhanced Raman spectroscopy for single molecular detection. Although plasmonics has been utilized since ancient times, the understanding of its basic interactions has not been fully achieved even under the emergence of modern nanoscience. In particular, it has been difficult to address the "ultra-fine" 1-10 nm regime, important for applications especially in bioimaging and biomedical areas, where neither classical nor quantum based theoretical methods apply.

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Glycosylation is an important post-modification reaction in plant secondary metabolism, and contributes to structural diversity of bioactive natural products. In plants, glycosylation is usually catalyzed by UDP-glycosyltransferases. Flavonoid 2'--glycosides are rare glycosides.

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Due to the general incompleteness of photochemical reactions, the photostationary structure in traditional photo-controlled host-guest self-assembly transfer is usually disordered or irregular. This fact readily affects the photoregulation or improvement of related material properties. Herein, a photoexcitation-induced aggregation molecule, hydroxyl hexa(thioaryl)benzene (HB), was grafted into β-cyclodextrin to form a host-guest system.

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Few-layer tin (Sn)-based nanosheets (NSs) with a thickness of ≈2.5 nm are successfully prepared using a modified liquid phase exfoliation (LPE) method. Here the first exploration of photo-electrochemical (PEC) and nonlinear properties of Sn NSs is presented.

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The intensive interest in expanded porphyrins can be attributed to their appealing photoelectric and coordination behavior. In this work, an N-confused heptaphyrin 1 was synthesized by an acid-catalyzed [3+4] condensation reaction. The introduction of an N-confused pyrrolic unit into the heptaphyrin macrocycle led to the formation of a figure-eight-like conformation with nonsymmetrical "NNNN" and "NNNC" coordination cavities employable for bimetallic coordination.

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Fused porphyrinoids have received increasing interest in light of their extended conjugation and unique coordination behavior. On the basis of our previously reported multiply fused pentaphyrin isomers and , a novel isomer has been synthesized in this work. possesses a hexacyclic fused moiety with a nearly coplanar CCNN cavity involving an inverted pyrrole, which is slightly different from the CNNN ones of and involving an N-confused pyrrole.

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Article Synopsis
  • Researchers aim to create a new assay using surface plasmon resonance (SPR) to identify compounds that can detect fibrillar forms of alpha-synuclein and 4-repeat tau, which are important in neurodegenerative diseases.
  • They optimized the SPR protocol to analyze the binding properties of various fluorescent ligands with different fibrils, identifying multiple binding sites on the fibrils and validating findings through immunofluorescence in brain tissue samples.
  • The study suggests that this SPR approach could effectively characterize small molecules for targeting proteinopathies associated with neurodegenerative diseases, improving our understanding of these conditions.
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Exfoliation of 2D non-Van der Waals (non-vdW) semiconductor nanoplates (NPs) from inorganic analogs presents many challenges ahead for further exploring of their advanced applications on account of the strong bonding energies. In this study, the exfoliation of ultrathin 2D non-vdW chromium sulfide (2D CrS) by means of a combined facile liquid-phase exfoliation (LPE) method is successfully demonstrated. The morphology and structure of the 2D CrS material are systematically examined.

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