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In this work, an Ag–Ti2SnC composite was fabricated by the hot-pressing sintering method, and the erosion behavior of Ag–Ti2SnC with volume percentages of 10–40% was studied at a load voltage of 10 kV. The arc life and breakdown current were observed at about 31–36 ms and 39 A, respectively. The cathode spot traveled the fastest on the surface of the Ag–40 vol% Ti2SnC composite. Due to emission center model, the temperature of the minor protrusions on the cathode surface increased, resulting in Ag ions, Ti ions, and Sn ions being generated. Combining with the ionized oxygen, Ag2O, AgO, TiO2, and SnO2 were formed on the eroded Ag–Ti2SnC surface after arc erosion. The research results will broaden the application range of Ag–Ti2SnC electrical contact material and enrich the arc erosion mechanism.

As a fundamental subject of medical education, human anatomy plays a critical role in the development of medical science. However, because of multiple factors including cultural conservativism and limited social understanding, China is facing a particularly severe shortage of bodies donated for anatomy education. Zhengzhou University (ZZU) has continued to uphold whole-body dissection as the preferred method for medical students to learn anatomy. For this study, records of registered individuals (who have signed a body donation agreement) and donors (whose bodies have been received) from 2001 to 2020 were collected and analyzed. The aim of this study was to explore the factors influencing the body donation program (BDP) at ZZU, and then reinforce the social understanding for the BDP. The results showed a significant increase in the numbers of both registered individuals and donors since 2015, which is the year the publicity and commemoration in honor of donors were increased. There were no significant differences between the biological male and female sexes in the registered individuals, but the number of male donors (12.85 ± 10.86, per year) was significantly higher than that of female donors (4.75 ± 4.53, per year). The current donor profile at ZZU is male in his 60/70s, while the profile of registered individuals is male or female in their 60s. Strengthening the publicity and commemoration in honor of donors may contribute to the implementation of BDPs.

The Triassic tectonic evolution and affinity among the Yangtze Block, Qinling Orogenic Belt and Songpan-Ganzi Terrane remain subjects of ongoing scientific debate. In this context, the sedimentary rocks of Xujiahe Formation (second segment) (T3x2) represent an ideal case for addressing this issue. In this study, new stratigraphic, geochemical and detrital zircon analyses have been conducted on two sections of the T3x2. The stratigraphic assemblage and features suggests a braided delta as the depositional setting. Whole-rock geochemical results indicate that the sandstones from the T3x2 exhibit moderate palaeo-weathering and primarily originate from upper crustal felsic rocks, mostly S-type granites. The detrital zircons within these sandstones display distinctive age peaks at intervals of 200-300 Ma, 700-900 Ma, and 1800-2000 Ma, similar to those from the Qinling Orogenic Belt. Both the clastic particle composition and whole-rock geochemistry indicates that the T3x2 sections were deposited in a tectonic environment transitioning from a passive to an active continental margin, highlighted by a braided delta influenced by rivers flowing from the northeast to the southwest. [ABSTRACT FROM AUTHOR]

In this paper, a numerical model coupling the smoothed particle hydrodynamics (SPH) with peridynamics (PD) is developed to solve the problem of the hydroelastic water entry. By combining the geometric nonlinear peridynamics with the weakly compressible SPH, the proposed model can efficiently simulate the nonlinear deformation of the structure and the deformation of a fluid free surface. The transmission of information between the fluid and solid phases is implemented by a dummy particle boundary treatment method. By simulating benchmark tests, the ability of the proposed model to solve nonlinear fluid–structure coupling problems is verified. In order to improve the computational efficiency, the graphics processing unit parallel acceleration scheme is applied to the SPH-PD model. Compared with the serial scheme, the speedup effect of the parallel scheme in large-scale computation is verified. As an application of the numerical model, the water entry of the flexible panel at a constant entry velocity is studied. The mechanism of hydroelastic effect is explained by analyzing the variations in the fluid pressure field, slamming force, and panel deformation during water entry. In addition, the influences of plate rigidity, impact velocity, and deadrise angle on the hydroelastic effect are investigated. [ABSTRACT FROM AUTHOR]

Wenshang sag is located in Shandong west uplift zone, surface quaternary cover. The Guanzhuang group in paleogene period is a saline rock system, and the research level of this area is low. By collecting the borehole data of past, Guanzhuang group in paleogene period in Wenshang sag of systematic classification and correlation could be divided into Guanzhuang group from the bottom-up Changlu formation, Zhujiagou formation and Dawenkou formation. Changlu formation is sedimentary fluvial facies, Zhujiagou formation is sedimentary piedmont pluvial facies, Dawenkou formation is lacustrine deposition. The rock assemblages of Dawenkou formation have obvious separability (upper, middle and lower segments), wherein the middle segments is containing the gypsum layer. The stratigraphic framework in the area was established, and the formation, evolution and metallogenic conditions were discussed. [ABSTRACT FROM AUTHOR]