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Bulletproof glass exhibits excellent impact resistance and protective capabilities against bullets, explosive fragments, high-speed projectiles, and various other aggressive threats, making it extensively utilized in the field of safety and security. To investigate the dynamic mechanical properties and constitutive relation of the inorganic glass layers in bulletproof glass under impact loading, we firstly employed an electronic universal testing machine and a split Hopkinson pressure bar (SHPB) test setup to obtain the tensile and compressive mechanical properties of the material at different strain rates. Results reveal a noticeable strain rate effect that the material's strength increases with the strain rate. Secondly, drawing on the experience of geotechnical triaxial compression tests, we designed a high-strength confinement sleeve suitable for assessing the mechanical properties of glass particles under conditions of complete damage. Results show a significantly lower strength compared to that of the intact state of inorganic glass. Finally, by integrating test data, an JH2 constitutive model for inorganic glass with damage was established. By using the non-linear finite element software LS-DYNA, the SHPB test process was simulated. The effectiveness of the constitutive model was verified by comparing test and simulated results. [ABSTRACT FROM AUTHOR]

This review used traditional and network meta-analyses (NMA) to conduct a comprehensive study of antithrombotic therapies in children with thromboembolic disease. We searched the PubMed, Embase, Cochrane Library, Web of Science and ClinicalTrials.gov databases from their inception to 26 February, 2023. And we finally included 16 randomized controlled trials. In the prevention of thromboembolic events (TEs), the use of anticoagulants had a low risk of TEs (relative risk (RR) 0.73, 95% CI 0.56 to 0.94) and a high risk of minor bleeding (RR 1.43, 95% CI 1.09 to 1.86) compared with no anticoagulants. In the treatment of TEs, direct oral anticoagulants (DOACs) were not inferior to standard anticoagulation in terms of efficacy and safety outcomes. In NMA, rivaroxaban and apixaban showed the lowest risk for TEs and major or clinically relevant nonmajor bleeding. According to the overall assessment of efficacy and safety, dabigatran may be the best choice for children with thromboembolic disease. The results of our study will provide references and suggestions for clinical drug selection. [ABSTRACT FROM AUTHOR]

The sapphire single crystal plate with size of 485 mm x 985 mm x 12 mm was successfully prepared by a large-size edgedefined film-fed growth (EFG) furnace designed and developed independently. After cutting and grounding, the crystal was formed into transparent armors composited with glass and polycarbonate. The surface density with the size of 352 mm x 351 mm x 33 mm is 79. 27 kg/m², and the surface density of the other is 79.38 kg/m² with the size of 351 mm x 342 mm x 33 mm. Targeting tests were conducted on the transparent armors using incendiary shells with diameters of 7.62 mm and 12.7 mm, respectively. The experimental results show that the transparent armor based on sapphire crystal plate has excellent impact resistance during firing at a normal angle of 0° and with a distance of 100 m which from target to the armors. [ABSTRACT FROM AUTHOR]

Flexible strain sensors have received widespread attention because of their great potential in many fields. Carbon nanotubes (CNTs) have been used as conductive materials for flexible strain sensors due to their excellent electrical and mechanical properties, and the fabricated flexible strain sensors have excellent sensing performance. This paper systematically summarizes the advances in flexible resistance‐type strain sensors based on CNTs. The strain sensing mechanisms are introduced, including crack extension, tunneling effect, and disconnection of overlapping materials. The performance parameters of the sensors, including sensitivity, stretchability, linearity, hysteresis, dynamic durability, and transparency, are discussed comprehensively. The coating methods, 3D printing techniques, chemical vapor deposition, transfer methods, and spinning processes used to fabricate CNT strain sensors are highlighted. The effect of isolated and porous internal conductive structures, folded and microcracked surface structures, films and fabrics macroscopic structures on sensor performance were systematically analyzed. The applications of the sensors in medical health, motion monitoring, gesture recognition, human–computer interaction, and soft robotics are provided in detail. Finally, the future challenges of CNT flexible strain sensors are summarized and the outlook is presented. Although CNT strain sensors have made great progress so far, there are still many problems that need researchers' attention and solutions. [ABSTRACT FROM AUTHOR]

In order to study the morphology of Fe-Ni alloy films and properties of coated glass at different heat treatment temperatures, the Fe-Ni alloy film is deposited on the glass substrate by vacuum electron beam heating evaporation technology. The structure of the film was analyzed by polycrystalline X-ray diffraction (XRD) and field emission scanning electron microscope (FESEM). Then the optical properties, electromagnetic properties, and electromagnetic shielding properties of the coated glass were tested. The results show that as the heat treatment temperature increases, the crystallinity of the films is better, and the body-centered cubic crystal phase gradually precipitates, which has the preferred orientation in (110) direction. Pores appear in the films when the heat treatment temperature is too high. The influence of heat treatment temperature on the haze of the coated glass is less than 1 %, but the visible light transmittance, surface sheet resistance, and relative permeability of the coated glass show a certain change with the change of heat treatment temperature. The shielding effectiveness of Fe-Ni alloy coated glass is more than 30 dB in the low-frequency electromagnetic waveband below 30 MHz, and the highest is 55 dB at 14 kHz. It is a preferred material for low-frequency electromagnetic shielding. [ABSTRACT FROM AUTHOR]