We have used laboratory and synchrotron x-ray diffraction to investigate the structural and chemical changes undergone by polycrystalline RbH(2)PO(4) upon heating within the 30-250 °C temperature interval. Our data show no evidence of the previously reported onset of partial polymerization at T = 96 °C (Park et al 2001 J. Phys.: Condens. Matter 13 9411) which was proposed as an explanation for the high-temperature proton conductivity enhancement in phosphate-based solid acids. Instead, we found that a tetragonal [Formula: see text] monoclinic polymorphic transition initiates at T≈90 °C. The transition is complete at T≈130 °C, and the new monoclinic RbH(2)PO(4) polymorph is stable upon further heating to T = 200 °C. Moreover, its crystal structure is isomorphic to that of monoclinic CsH(2)PO(4). This remarkable similarity suggests that the microscopic structures and dynamics responsible for the high-temperature superprotonic behavior of RbH(2)PO(4) could be the same as those of its Cs-based counterpart.
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http://dx.doi.org/10.1088/0953-8984/21/32/325401 | DOI Listing |
ACS Appl Mater Interfaces
December 2024
Center for Optics Research and Engineering, State Key Laboratory of Crystal Materials, Shandong University, Qingdao 266237, China.
Shear mode ultrasonic waves are in high demand for structural health monitoring (SHM) applications owing to their nondispersive characteristics, singular mode, and minimal energy loss, especially in harsh environments. However, the generation and detection of a pure shear wave using conventional piezoelectric materials present substantial challenges because of their complex piezoelectric response, involving multiple modes. Herein, we introduce a high-quality piezoelectric crystal BiSiO (BSO), exhibiting a robust piezoelectric response ( = 45.
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December 2024
Centre Énergie, Matériaux Télécommunications, Institut National de la Recherche Scientifique, 1650, Blvd, Lionel-Boulet, Varennes, QC, J3X-1P7, Canada.
RF-sputtering is used to deposit TiO-Magneli-phase films onto various substrates at deposition temperatures (T) ranging from 25 to 650 °C. Not only the structural, but also electrical conductivity, optical absorbance and photothermal properties of the TiO films are shown to change significantly with T. A T of 500 °C is pointed out as the optimal temperature that yields highly-crystalized pure-TiO-Magneli phase with a densely-packed morphology and a conductivity as high as 740 S/cm.
View Article and Find Full Text PDFSmall Methods
December 2024
Nanchang Key Laboratory of Photoelectric Conversion and Energy Storage Materials, College of Science, Nanchang Institute of Technology, Nanchang, 330099, P. R. China.
Constructing a hollow structure inside zeolite is very helpful for improving its performance. Unlike the conventional alkaline etching technique usually operated at high temperature (typically 170 °C) and high pressure (autogenerated in autoclave), here, it is discovered that zeolite MFI nano-box can be achieved under mild etching conditions of atmospheric pressure and low temperature of 80 °C, making it very attractive for energy conservation and practical applications. A hollow-structure formation mechanism of protection-dissolution etching is demonstrated by characterizing MFI crystals obtained under different etching time, temperature, and etchant concentration.
View Article and Find Full Text PDFFront Vet Sci
December 2024
College of Animal Science and Technology, Guangxi University, Nanning, China.
Porcine hemagglutinating encephalomyelitis virus (PHEV), porcine pseudorabies virus (PRV), and classical swine fever virus (CSFV) are currently prevalent worldwide and cause similar neurological symptoms in infected pigs. It is very important to establish a detection method that can rapidly and accurately detect and differentiate these three viruses. Targeting the PHEV N gene, PRV gB gene, and CSFV 5' untranslated region (5'UTR), three pairs of specific primers and probes were designed, and a triplex crystal digital reverse transcription-PCR (cdRT-PCR) was developed to detect PHEV, PRV, and CSFV.
View Article and Find Full Text PDFProtein Sci
January 2025
Graduate School of Life and Environmental Sciences, Kyoto Prefectural University, Kyoto, Japan.
Antibodies and antibody mimics are extensively used in the pharmaceutical industry, where stringent safety standards are required. Implementing heat sterilization during or after the manufacturing process could help prevent contamination by viruses and bacteria. However, conventional antibodies and antibody mimics are not suitable for heat sterilization because they irreversibly denature at high temperatures.
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