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To investigate the deterioration characteristics of filling body combinations and surrounding rock in excavating technology without coal pillars in the original roadway filling, uniaxial loading destructive tests and cyclic loading and unloading tests were conducted with various combinations of two, three, and four lithologies to analyze strength characteristics, energy storage, and dissipation laws. The results indicate that when the filling is combined with another lithology, strengthening degree of the filling is negatively correlated with the height of other lithology; the higher the strength of the material combined with the filling, the greater the amplitude of the weakening. The filling exhibits a faster speed and higher upper limit of elastic energy storage compared to mudstone. When filling is combined with two or three lithologies, the strength weakening degree is negatively correlated with their height ratio. However, under same cycles, elastic energy of coal-free combinations has a faster storage speed and a higher upper limit, while coal-containing combinations exhibit higher energy dissipation. During tests, the elastic energy of different lithological combinations is linearly related to the number of cycles, and the energy is divided into four stages. The damage variable is exponentially related to the height of the roof and floor. The intrinsic model was modified using the stress-strain relationship considering the internal damage factor in front of the peak and verified to accurately simulate the deformation damage of the combined body.
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http://dx.doi.org/10.1038/s41598-025-03927-3 | DOI Listing |
Inorg Chem
September 2025
College of Chemistry and Chemical Engineering, Key Laboratory of Shandong Provincial Universities for Functional Molecules and Materials, Qingdao University, Qingdao, Shandong 266071, P. R. China.
Molecular piezoelectrics have garnered significant attention in energy harvesting and sensing fields due to their high intrinsic piezoelectricity, low elastic properties, and excellent solution processability. Recent efforts have primarily focused on rationally tuning the piezoelectric performance of these materials through the molecular predesign of organic components. However, the regulation of piezoelectric properties via the central metal ion has remained relatively underexplored.
View Article and Find Full Text PDFAdv Mater
September 2025
Department of Engineering Science, University of Oxford, Oxford, OX1 3PJ, UK.
Hydrogen embrittlement (HE) poses a significant challenge to the durability of materials used in hydrogen production and utilization. Disentangling the competing nanoscale mechanisms driving HE often relies on simulations and electron-transparent sample techniques, limiting experimental insights into hydrogen-induced dislocation behavior in bulk materials. This study employs in situ Bragg coherent X-ray diffraction imaging to track three-dimensional (3D) dislocation and strain field evolution during hydrogen charging in a bulk grain of austenitic 316 stainless steel.
View Article and Find Full Text PDFLangmuir
September 2025
Neutron Scattering Division, Oak Ridge National Laboratory, MS 6473, Oak Ridge, Tennessee 37831 United States.
Mordenite ((Ca,Na,K)AlSiO·7HO) is a natural and synthetic nanoporous zeolite containing several channels of different sizes in its structure. Because of this, its structure provides an important opportunity to study the relationship between confined and ultraconfined water as these channels have sizes between those typical of these water environments. In this study, the properties of water molecules in these environments were analyzed using inelastic and quasielastic neutron spectroscopy of a natural mordenite.
View Article and Find Full Text PDFInvest Ophthalmol Vis Sci
September 2025
Eye Center, The Second Affiliated Hospital, School of Medicine, Zhejiang University, Zhejiang Provincial Key Laboratory of Ophthalmology. Zhejiang Provincial Clinical Research Center for Eye Diseases, Zhejiang Provincial Engineering Institute on Eye Diseases, Hangzhou, People's Republic of China.
Purpose: Evidence on the association between visceral obesity and diabetic retinopathy (DR) remains sparse and debatable. We aimed to use three novel indicators, body roundness index (BRI), lipid accumulation product (LAP), and visceral adiposity index (VAI), to investigate the longitudinal relationship between visceral obesity and DR, and explore the potential metabolic mechanisms.
Methods: In this prospective study based on the UK Biobank (UKB), 14,738 individuals with diabetes free of DR at baseline were included.
ACS Omega
September 2025
Materials and Manufacturing Directorate, AFRL/RXEE, Air Force Research Laboratory, Wright-Patterson AFB, Ohio 45433, United States.
This study addresses a critical limitation in direct bonded copper (DBC) materials used in power electronics by introducing a copper-zirconium (Cu/Zr) alloy interposing layer at the copper-ceramic interface. This novel design aims to mitigate mechanical stress induced by mismatched material properties, such as the coefficient of thermal expansion (CTE) and elastic modulus, during thermal cycling. The key findings of this study are (1) thermal fatigue improvement: Test samples with the Cu/Zr interface layer (Cu-Cu/Zr-AlN) three times enhanced thermal fatigue resistance, surviving 30 thermal cycles from -55 to 300 °C before delamination, while standard DBC substrates without the Cu/Zr layer failed after just 10 cycles, indicating a performance improvement with the Cu/Zr alloy, (2) durability projections: Based on the Coffin-Manson model, if the upper temperature is capped at 150 °C, the Cu-Cu/Zr-AlN substrates are projected to survive approximately 1372 cycles, underscoring their potential for long-term reliability, and (3) stress mitigation: The Cu/Zr alloy layer bridges the CTE disparity between copper and ceramic, reducing mechanical stress and improving structural integrity across a broad temperature range (-55 to 300 °C).
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