Arcing is a ubiquitous phenomenon and a crucial issue in high-voltage applied systems, especially low-temperature plasma (LTP) engineering. Although arcing in LTPs has attracted interest due to the severe damage it can cause, its underlying mechanism has yet to be fully understood. To elucidate the arcing mechanism, this study investigated various signals conventionally used to analyze arcing such as light emission, arcing current and voltage, and background plasma potential. As a result, we found that light emission occurs as early as 0.56 μs before arcing current initiation, which is a significant indicator of the explosive development of arcing as well as other signals. We introduce an arcing inducing probe (AIP) designed to localize arcing on the tip edge along with multiple snapshot analysis since arcing occurs randomly in space and time. Analysis reveals that the prior light emission consists of sheath and tip glows from the whole AIP sheath and the AIP tip edge, respectively. Formation mechanisms of these emissions based on multiple snapshot image analysis are discussed. This light emission before arcing current initiation provides a significant clue to understanding the arcing formation mechanism and represents a new indicator for forecasting arcing in LTPs.
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http://dx.doi.org/10.1038/s41598-022-25550-2 | DOI Listing |
Environ Res
January 2025
School of Materials and Chemistry, University of Shanghai for Science and Technology, Shanghai 200093, China. Electronic address:
The pressing necessity to mitigate climate change and decrease greenhouse gas emissions has driven the advancement of heterostructure-based photocatalysts for effective CO₂ reduction. This study introduces a novel heterojunction photocatalyst formed by integrating potassium-doped polymeric carbon nitride (KPCN) with metallic Zn₃N₂, synthesized via a microwave-assisted molten salt method. The resulting Schottky contact effectively suppresses the reverse diffusion of electrons, achieving spatial separation of photogenerated charges and prolonging their lifetime, which significantly enhances photocatalytic activity and efficiency.
View Article and Find Full Text PDFBiomacromolecules
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Polymer Research Centre and Centre for Advanced Functional Materials, Department of Chemical Sciences, Indian Institute of Science Education and Research Kolkata, Nadia, Mohanpur 741246, West Bengal, India.
The present investigation aims to develop a reactive oxygen species (ROS) and esterase-responsive biodegradable mannosylated polyurethane to effectively deliver the encapsulated antileishmanial drug amphotericin B (AmB) selectively to infected macrophage cells. Owing to suitable amphiphilic balance, the as-synthesized glycosylated polyurethane () with aryl boronic ester-based diol () moiety as ROS-trigger, water-soluble mannose pendants, and fluorescent 4,4-difluoro-4-bora-3a,4a-diaza--indacene (BODIPY) chain ends for bioimaging formed nanoaggregates in an aqueous medium as confirmed by H NMR spectroscopy, dynamic light scattering (DLS), field emission scanning electron microscopy (FESEM), transmission electron microscopy (TEM), and critical aggregation concentration (CAC) measurements. Aided by two endogenous stimuli present in phagolysosome, ROS and esterase, AmB-encapsulated polymeric nanoaggregates as drug delivery vehicles achieved an efficient reduction of both and intracellular amastigote burden compared to the free AmB.
View Article and Find Full Text PDFPhys Rev Lett
December 2024
Department of Physics and Astronomy and Center for Fundamental Physics, Northwestern University, Evanston, Illinois 60208, USA.
We introduce a novel technique for enhancing the robustness of light-pulse atom interferometers against the pulse infidelities that typically limit their sensitivities. The technique uses quantum optimal control to favorably harness the multipath interference of the stray trajectories produced by imperfect atom-optics operations. We apply this method to a resonant atom interferometer and achieve thousandfold phase amplification, representing a 50-fold improvement over the performance observed without optimized control.
View Article and Find Full Text PDFAlzheimers Dement
December 2024
Harvard Medical School, Boston, MA, USA; Brigham and Women's Hospital/Massachusetts General Hospital, Boston, MA, USA.
Background: Apathy is a common neuropsychiatric symptom of Alzheimer's disease (AD) and has been linked to greater levels of AD biomarkers (i.e., global cortical amyloid burden and regional tau levels) in preclinical individuals.
View Article and Find Full Text PDFJ Am Chem Soc
January 2025
McKetta Department of Chemical Engineering and Texas Material Institute, The University of Texas at Austin, Austin, Texas 78712, United States.
Germanium (Ge) colloidal quantum dots (CQDs) were synthesized by thermal decomposition of GeI using capping ligand mixtures of oleylamine (OAm), octadecene (ODE), and trioctylphosphine (TOP). Average diameters could be tuned across a wide range, from 3 to 18 nm, by adjusting reactant concentrations, heating rates, and reaction temperatures. OAm promotes decomposition of GeI to Ge and serves as a weakly bound capping ligand.
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