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A new instrumental neutron activation analysis (INAA) for the simultaneous determination of titanium (TiO) and silica (SiO) dioxide as UV-filters in sunscreens is described. Samples are encapsulated, neutron irradiated (30 s) and after a suitable decay (3 min), the induced Ti (T = 5.76 min) and Al (T = 6.56 min) radionuclides are measured for the emitted γ-ray fingerprint. Three applications were carried out: (i) screening study (analysis of commercial sunscreens in combination with single particle inductively coupled plasma mass spectrometry (sp-ICP-MS); (ii) research study (development of innovative UV-filters such as titanium dioxide or bismuth titanate loaded inorganic mesoporous silica nanoparticles, MSN); (iii) validation study (intercalibration of a spectrochemical method - inductively coupled plasma optical emission spectrometry, ICP-OES). Collectively, the nuclear method appears a powerful tool adequate for quantifying TiO and SiO in the above studies. The limited accessibility at the nuclear reactor for neutron activation is probably one of the reasons why the excellent characteristics of the nuclear technique are not always fully known and exploited in the industrial and research chemical world.
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http://dx.doi.org/10.1016/j.aca.2022.339601 | DOI Listing |
Adv Sci (Weinh)
September 2025
Department Chemie- und Bioingenieurwesen, Lehrstuhl für Chemische Reaktionstechnik (CRT), Friedrich-Alexander-Universität Erlangen-Nürnberg (FAU), Egerlandstr. 3, 91058, Erlangen, Germany.
The supported catalytically active liquid metal solution (SCALMS) concept is based on catalytically active metals dissolved in a low-melting-point liquid metal matrix. These solid alloy particles, deposited over a high area support, transform into a liquid alloy under reaction conditions. In this work, GaPt SCALMS materials of varying composition are investigated and focus on the change in the alloy composition during preheating, the actual high temperature propane dehydrogenation at 823 K, and after cool-down.
View Article and Find Full Text PDFPhys Chem Chem Phys
September 2025
Dubna State University, 141982 Dubna, Russia.
Boron nitride quantum dots combine several unique properties, including chemical stability, biocompatibility, and low cytotoxicity. These properties and tunable optical characteristics make them promising for use in boron neutron capture therapy simultaneously as therapeutic agents and fluorescent markers for cancer cells. In this paper we present a case study, in which the electronic structure of these dots is analyzed using DFT and TD-DFT methods providing a deeper understanding of their absorption properties.
View Article and Find Full Text PDFAngew Chem Int Ed Engl
September 2025
College of Materials Science and Opto-electronic Technology, Center of Materials Science and Optoelectronics Engineering, University of Chinese Academy of Sciences, Beijing, 100049, China.
High-voltage operation enables sodium-sufficient O3-type layered oxides to approach the maximum achievable energy densities for practical sodium-ion batteries (SIBs). This high-voltage regime, however, induces structural degradation strongly correlated with oxygen redox activity, a mechanism still incompletely resolved. Using prototypical O3-type NaNiFeMnO (NFM) as a model system, we identify the origin of this instability as a detrimental feedback loop between σ-type oxygen redox and cation migration.
View Article and Find Full Text PDFFEBS J
September 2025
Neutron Scattering Division, Oak Ridge National Laboratory, USA.
Serine hydroxymethyltransferase (SHMT) is a critical enzyme in the one-carbon (1C) metabolism pathway catalyzing the reversible conversion of L-Ser into Gly and concurrent transfer of 1C unit to tetrahydrofolate (THF) to give 5,10-methylene-THF (5,10-MTHF), which is used in the downstream syntheses of biomolecules critical for cell proliferation. The cellular 1C metabolism is hijacked by many cancer types to support cancer cell proliferation, making SHMT a promising target for the design and development of novel small-molecule antimetabolite chemotherapies. To advance structure-assisted drug design, knowledge of SHMT catalysis is crucial, but can only be fully realized when the atomic details of each reaction step governed by the acid-base catalysis are elucidated by visualizing active site hydrogen atoms.
View Article and Find Full Text PDFACS Nano
September 2025
Materials Genome Institute, Shanghai University, Shanghai 200444, China.
RuO, the benchmark catalyst for the oxygen evolution reaction (OER), has traditionally been considered Pauli paramagnetic; however, recent findings have demonstrated its antiferromagnetic (AFM) properties, hinting at the opportunity to enhance RuO's OER performance by manipulating its magnetic traits. In this study, we successfully induced weak ferromagnetism in commercial RuO, transitioning it from an AFM state using an electrochemical sodiation method. This process resulted in high activity, achieving an overpotential of 145 mV to reach 10 mA cm and extending the service hours by more than 13 times compared to pristine RuO in 0.
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