Brown carbon aerosols show obvious light absorption properties in the ultraviolet-visible (UV-Vis) range, which has an important impact on photochemistry and climate. In this study, experimental samples originated from the North slope of the Qinling Mountains (at two remote suburb sites) to study the optical properties of water-soluble brown carbon (WS-BrC) in PM. The WS-BrC of TY (a sampling site on the edge of Tangyu of Mei county) has a stronger light absorption ability than CH (a rural sampling site, near the Cuihua Mountains scenic spot). The direct radiation effect of WS-BrC relative to elemental carbon (EC) is 6.67 ± 1.36% in TY and 24.13 ± 10.84% in CH in the UV range, respectively. In addition, two humic-like and one protein-like fluorophore components in WS-BrC were identified by fluorescence spectrum and parallel factor (EEMs-PARAFAC). Humification index (HIX), biological index (BIX) and fluorescence index (FI) together showed that the WS-BrC in the two sites may originate from fresh aerosol emissions. Potential source analysis of Positive Matrix Factorization (PMF) model show that the combustion process, vehicle, secondary formation and road dust are the main contributors to WS-BrC.
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http://dx.doi.org/10.1016/j.envpol.2023.121641 | DOI Listing |
Nanotechnology
January 2025
Centre for Analysis and Synthesis, NanoLund, Lund University, Box 124, Lund, 221 00, SWEDEN.
Developing a reliable procedure for the growth of III-V nanowires (NW) on silicon (Si) substrates remains a significant challenge, as current methods rely on trial-and-error approaches with varying interpretations of critical process steps such as sample preparation, Au-Si alloy formation in the growth reactor, and nanowire alignment. Addressing these challenges is essential for enabling high-performance electronic and optoelectronic devices that combine the superior properties of III-V NW semiconductors with the well-established Si-based technology. Combining conventional scalable growth methods, such as Metalorganic Chemical Vapor Deposition (MOCVD) with in situ characterization using Environmental Transmission Electron Microscopy (ETEM-MOCVD) enables a deeper understanding of the growth dynamics, if that knowledge is transferable to the scalable processes.
View Article and Find Full Text PDFASN Neuro
January 2025
Center for Molecular Medicine and Genetics, Wayne State University School of Medicine, Detroit, MI, USA.
In light of the increasing importance for measuring myelin ratios - the ratio of axon-to-fiber (axon + myelin) diameters in myelin internodes - to understand normal physiology, disease states, repair mechanisms and myelin plasticity, there is urgent need to minimize processing and statistical artifacts in current methodologies. Many contemporary studies fall prey to a variety of artifacts, reducing study outcome robustness and slowing development of novel therapeutics. Underlying causes stem from a lack of understanding of the myelin ratio, which has persisted more than a century.
View Article and Find Full Text PDFInorg Chem
January 2025
Department of Chemistry, University of Southern California, Los Angeles, California 90089, United States.
The functional properties of tetraaryl compounds, M(aryl) (M = transition metal or group 14 element), are dictated not only by their common tetrahedral geometry but also by their central atom. The identity of this atom may serve to modulate the reactivity, electrochemical, magnetic, and optical behavior of the molecular species, or of extended materials built from appropriate tetraaryl building blocks, but this has not yet been systematically evaluated. Toward this goal, here we probe the influence of Os(IV), C, and Si central atoms on the spectroelectrochemical properties of a series of redox-active tetra(ferrocenylaryl) complexes.
View Article and Find Full Text PDFPLoS One
January 2025
School of Ophthalmology and Optometry, Wenzhou Medical University, Zhejiang, P. R. China.
Purpose: To evaluate the corneal biomechanical properties of phacoemulsification in the treatment of cataract patients.
Methods: Pertinent studies were searched in PubMed, EMBASE, Web of Science and clinicaltrials.gov.
Inorg Chem
January 2025
Department of Chemistry, College of Sciences, Northeastern University, Shenyang, Liaoning 110819, China.
Copper-based halides have attracted significant attention due to their unique photophysical properties and diverse coordination configurations. However, enhancing water stability and modulating structural transitions in cuprous halide materials remain challenging. In this work, we successfully synthesized three copper(I) halides, (CHP)CuBr (L1, [CHP] = hexyltriphenylphosphonium), (CHP)CuBr (L2), and (CHP)CuI (L3), via solvent volatilization, demonstrating exceptional water stability even after 27 days of submersion.
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