High-pressure behaviours of isomorphous HoMn(2)O(5) and BiMn(2)O(5) (Pbam, Z = 4) were studied, using Raman spectroscopy and single-crystal x-ray diffraction, with the samples in diamond anvil cells pressurized to 10.09 GPa and 8.54 GPa, respectively, at room temperature. No phase transition was detected in either material. The two manganates are most compressible along the a axis with the lattice contractions along the b and c directions nearly the same. Their P-V data fitted with the second-order Birch-Murnaghan equation of state (B' = 4.0) give the bulk moduli B(0) = 138(2) GPa for BiMn(2)O(5) and B(0) = 173(3) GPa for HoMn(2)O(5). The difference in bulk moduli results from BiMn(2)O(5) being more compressible than HoMn(2)O(5) along the a axis. Our study shows that the Mn-O frameworks in isomorphous RMn(2)O(5) compounds (R = Bi and rare earth) are not rigid at high pressures, but rather adapt to the behaviour of the coordination spheres around the R atoms. Bond valence calculations indicate that the pressure-induced charge transfers between the two Mn sites have different characters for the two compounds.
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http://dx.doi.org/10.1088/0953-8984/22/27/275401 | DOI Listing |
Food Chem X
January 2025
Faculty of Food Science and Engineering, Kunming University of Science and Technology, Kunming, 650500, China.
Legume proteins have recently gained significant interest in the food industry for their eco-friendliness and nutritional qualities. Research shows that the replacement of specific animal protein sources with legume proteins presents sustainability and economic benefit. Nonetheless, legume proteins frequently exhibit inferior functional properties and palatability compared to animal proteins.
View Article and Find Full Text PDFJ Hazard Mater
January 2025
State Key Laboratory of Advanced Environmental Technology, Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, Guangzhou, 510640, China; Guangdong-Hong Kong-Macao Joint Laboratory for Environmental Pollution and Control and Guangdong Provincial Key Laboratory of Environmental Protection and Resources Utilization, Guangzhou 510640, China.
The effects of micro- and nano-plastics (MNPs) on human health are of global concern because MNPs are ubiquitous, persistent, and potentially toxic, particularly when bound to atmospheric fine particles (PM). Traditional quantitative analysis of MNPs by pyrolysis-gas chromatography-mass spectrometry (Py-GC/MS) is often inaccurate because of false positive signals caused by similar polymers and organic compounds. In this study, a reliable analytical strategy combining HNO digestion and chromatographic peak reconstruction was developed to improve the precision of pyrolysis-gas chromatography-mass spectrometry analysis of multiple MNPs bound to PM.
View Article and Find Full Text PDFPhys Chem Chem Phys
January 2025
School of Materials and Energy, University of Electronic Science and Technology of China, Chengdu 611731, Sichuan, China.
The structural stability of the energetic material 2,2',4,4',6,6'-hexanitrostilbene (-HNS) under high pressure is critical for optimizing its detonation performance and low sensitivity. However, its structural response to external pressure has not been sufficiently investigated. In this study, high-pressure single-crystal X-ray diffraction data of -HNS demonstrate that the sample exhibits pronounced anisotropic strain, demonstrating an unusual negative linear compressibility (NLC) along the axis, with a coefficient of -4.
View Article and Find Full Text PDFEnviron Sci Pollut Res Int
January 2025
Council for Geoscience, Private Bag X112, Pretoria, 0001, South Africa.
One-step high-pressure and high-temperature direct aqueous mineral carbonation of tailings derived from mining of Platinum Group Metals in South Africa requires a fundamental understanding of the reactivity of the most dominant mineral phases, i.e. pyroxene and plagioclase (66 wt.
View Article and Find Full Text PDFFoods
January 2025
Food Studies and Policies Section, Food Safety Department, Dubai Municipality, Dubai P.O. Box 330127, United Arab Emirates.
High-pressure processing (HPP) is used as a non-thermal approach for controlling microbial viability. The purposes of this study were to (i) establish the decimal reduction times (D-values) for pathogenic bacteria during 350 MPa HPP treatment,; (ii) evaluate the impact of 350 MPa HPP on total plate count (TPC), yeasts and molds (YM), and lactic acid bacteria (LAB) in camel milk; (iii) investigate the behavior of several spoilage-causing bacteria during storage at 4 °C and 10 °C for up to 10 d post-HPP treatment; and (iv) assess the effect of HPP on the protein degradation of camel milk. The D-values for , O157:H7, and spp.
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