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Polychlorinated biphenyls (PCBs) are persistent organic pollutants which are widely present in environment and harmful to human health. In this study, an efficient and convenient magnetic solid phase extraction method with C modified magnetic polyamido-amine (PAMAM) dendrimers as sorbents was established for enriching trace amounts of PCBs in beverage samples. Gas chromatography-tandem mass spectrometry (GC-MS/MS) was utilized for analysis of PCBs. Parameters affecting extraction efficiency were optimized. Under optimal parameters, good linearity can be achieved in concentration range of 0.001-20 μg L and 0.002-20 μg L for nine selected PCBs. The limits of detection for PCBs were in the range of 0.1-0.2 ng L. The spiked recoveries were in the range of 87.0 %-115.1 % (n = 3). The results proved that this established method was reliable for monitoring trace PCBs in beverage samples.
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http://dx.doi.org/10.1016/j.foodchem.2022.133683 | DOI Listing |
Proc Natl Acad Sci U S A
September 2025
Geballe Laboratory for Advanced Materials, Stanford University, Stanford, CA 94305.
The iron-based high-[Formula: see text] superconductors (SCs) exhibit rich phase diagrams with intertwined phases, including magnetism, nematicity, and superconductivity. The superconducting [Formula: see text] in many of these materials is maximized in the regime of strong nematic fluctuations, making the role of nematicity in influencing the superconductivity a topic of intense research. Here, we use the AC elastocaloric effect (ECE) to map out the phase diagram of Ba(FeCo)As near optimal doping.
View Article and Find Full Text PDFmSphere
September 2025
Department of Chemistry, Michigan State University, East Lansing, Michigan, USA.
The structural role of β-1,6-glucan has remained under-investigated in filamentous fungi compared to other fungal cell wall polymers, and previous studies have shown that the cell wall of the mycelium of did not contain β-1,6-glucans. In contrast, the current solid-state NMR investigations showed that the conidial cell wall contained a low amount of β-1,6-glucan. ssNMR comparisons of the and β-1,6-glucans showed they are structurally similar.
View Article and Find Full Text PDFMagn Reson Lett
May 2025
National Center for Magnetic Resonance in Wuhan, State Key Laboratory of Magnetic Resonance and Atomic and Molecular Physics, Wuhan Institute of Physics and Mathematics, Innovation Academy for Precision Measurement Science and Technology, Chinese Academy of Sciences, Wuhan, 430071, China.
Organic structure directing agents (OSDAs), such as tetrapropylammonium (TPA) cations, serve as crucial templates for the formation of zeolite frameworks. These organic molecules interact with inorganic species, guiding the assembly of the zeolite structure. In this study, we investigate the complex interplay between boron species and TPA cations during the crystallization of [B, Al]-ZSM-5 zeolites.
View Article and Find Full Text PDFMagn Reson Lett
May 2025
The State Key Laboratory of Magnetic Resonance and Atomic and Molecular Physics, Innovation Academy for Precision Measurement Science and Technology, Chinese Academy of Sciences, Wuhan 430071, China.
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View Article and Find Full Text PDFSci Technol Adv Mater
August 2025
Research Center for Electronic and Optical Materials, National Institute for Materials Science, Tsukuba, Ibaraki, Japan.
We measured the residual stress tensor in a nitrogen-doped chemical vapor deposition (001) diamond film. The stress tensor was evaluated from the amount of the shift in optically detected magnetic resonance (ODMR) spectra of NV center in the diamond. A confocal microscopy setup was used to observe the spatial variation of the stress tensor in the diamond film.
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