In this paper, we present the results of research on the thermoluminescence (TL) and optical absorption (OA) properties of colorless natural quartz (including natural quartz samples, sodium ion (Na) rich samples (by diffusion), and alkali metal (M) ion poor samples (by sweep)). In detail, the relationship between the TL glow peaks and the emission wavelength was determined. The dynamics parameters ( , , ) have been computed for all TL peaks on the glow curve. The recombination mechanism electron-hole with the participation of the region energy has been determined for all electron traps in the temperature range of 50-430 °C through thermally stimulated conductivity measurement (TSC). Nonlinearity and approaching signal saturation are observed at doses above 22 Gy for the electron trap at 110 °C, above 45 Gy for the electron trap at 238 °C, and 80 Gy for the electron traps at 325 °C and 375 °C. The role of irradiation and heat treatment in the formation of absorption centers as well as the relationship of these centers to electronic traps have been also investigated in detail. The role of M ions and hydrogen ions (H) for the absorption bands in the UV-vis region has been discussed. The results of the combination of the TL measurement and monochromatic light absorption according to temperature show that the TL process occurs concurrently with the reduction of the absorbent center produced in the irradiation process.
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http://dx.doi.org/10.1039/d4ra03116d | DOI Listing |
Appl Biochem Biotechnol
December 2024
School of Metallurgy, Northeastern University, Shenyang, China.
Electrochemical and shake flask tests were used to examine the corrosion characteristics of typical gangue minerals in biometallurgical systems and their impact on microbial communities. The results show that the solubility order of the three gangue minerals is feldspar, mica, and quartz in descending order. Their corrosion processes are mainly controlled by cathodic electron-donating processes.
View Article and Find Full Text PDFAdv Mater
December 2024
College of Physics and Center of Quantum Materials and Devices, Chongqing University, Chongqing, 401331, China.
Achieving efficient and sustainable hydrogen production through photocatalysis is highly promising yet remains a significant challenge, especially when replacing costly noble metals with more abundant alternatives. Conversion efficiency with noble-metal-free alternatives is frequently limited by high charge recombination rates, mainly due to the sluggish transfer and inefficient consumption of photo-generated holes. To address these challenges, a rational design of noble-metal-free cocatalysts as oxidative sites is reported to facilitate hole consumption, leading to markedly increased H yield rates without relying on expensive noble metals.
View Article and Find Full Text PDFEnviron Geochem Health
December 2024
Research Institute of Mines and Environment (RIME), Université du Québec en Abitibi-Témiscamingue (UQAT), 445 Boul. de l'Université, Rouyn-Noranda, QC, J9X 5E4, Canada.
Phosphate mines produce large quantities of waste rock. These waste rocks are mixed and managed on the surface as large unrestored piles, which makes them difficult to rehabilitate. They primarily comprise carbonates, clays, marls, and cherts (flints).
View Article and Find Full Text PDFACS Appl Mater Interfaces
December 2024
Technical University of MunichTUM School of Natural Sciences, Department of Chemistry, WACKER-Chair of Macromolecular Chemistry, Lichtenbergstraße 485748 Garching, Germany.
Herein, novel, superabsorbent, and pH-responsive hydrogels obtained by the photochemical cross-linking of hydrophilic poly(vinylphosphonates) are introduced. First, statistical copolymers of diethyl vinylphosphonate (DEVP) and diallyl vinylphosphonate (DAlVP) are synthesized via rare earth metal-mediated group-transfer polymerization (REM-GTP) yielding similar molecular weights ( = 127-142 kg/mol) and narrow polydispersities ( < 1.12).
View Article and Find Full Text PDFEnviron Sci Pollut Res Int
December 2024
Departamento de Química, ICEx, Universidade Federal de Minas Gerais, Avenida Antônio Carlos, Belo Horizonte, MG, 6627, 370901, Brazil.
The development of methods for determining volatile and semi-volatile organic compounds in public spaces has become necessary to identify potential health and environmental risks. This study presents a practical methodology for sampling, extracting, detecting, and identifying these compounds in a vehicular traffic region in Belo Horizonte, Brazil. The methodology uses direct-immersion solid phase microextraction (DI-SPME) and static headspace (SHS) to extract SVOCs/VOCs.
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