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Node-containing straws exhibit superior mechanical properties compared to node-free straw plants, particularly in terms of shear resistance and compression resistance. We explore the relationship between the structure and mechanical properties of straw materials, providing deeper insights for the field of biomechanics. In this study, we focused on two node-containing straw plants, namely sorghum and reed. The main characteristics of sorghum and reed stalks were compared using macroscopic observation, stereomicroscopy, scanning electron microscopy, infrared spectroscopy, and EDS analysis. This study revealed numerous similarities and differences in the macro- and microstructures as well as the elemental composition of sorghum and reed stalks. The functional groups in sorghum and reed stalks were largely similar, with the primary elements being C and O. Distinguishing features included a higher tapering and a slightly larger reduction in wall thickness in sorghum stalks compared to reed stalks. The cross-section of sorghum stalks was filled with pith structures, while reed stalks exhibited a hollow structure. The vascular bundles in sorghum typically showed a paired arrangement, whereas those in reeds were arranged in odd numbers. Furthermore, sorghum straws contained more Cl and no Br, while the parenchyma of reed straws contained higher Br. The C and O proportions of sorghum straws and reed straws are 50–53% (50–51%) and 45–46% (48–49%), respectively. These variations in elemental composition are believed to be correlated with the mechanical properties of the materials. By conducting a detailed study of the micro/macrostructures and material composition of sorghum and reed straw, this paper provides valuable insights for the field of biomechanics. [ABSTRACT FROM AUTHOR]

A series of photosensitive zirconia ceramic slurry with adjustable viscosity and cured depth have been presented for the construction of high‐quality zirconia ceramic fabricated by digital light processing 3D printing. The rheological and curing behavior of the slurry can be flexibly optimized by tuning the reactive diluent concentration and category, since the change of dominant position of diluent on viscosity and the different curing mode. Monofunctional reactive diluent (HEA, hydroxyethyl acrylate) exhibits an enhanced dilution effect compared with that of bifunctional reactive diluent (HDDA, 1,6‐hexamethylene diacrylate) due to the lower molecular mass of monofunctional diluent. As a result, the viscosity reaches lower than 2000 mPa·s when the concentration of both HEA and HDDA exceeds 50 wt.%. At the same time, the non‐Newtonian properties of the slurry are also changed, which facilitates the printing process. However, excessive addition of diluent may generate more defects in ceramic green body. Consequently, the cured depth of zirconia slurry can reach 55 and 50 µm, respectively, at the curing time of 3 s while introducing the HEA or HDDA with the concentration below 70 wt.%, and the modified feedstock is promising for high‐quality and low‐defect zirconia ceramic components printing for biomedical applications. [ABSTRACT FROM AUTHOR]

In this paper, the multiangle's crashworthiness of the bionic tubes inspired by the cylindrical fibers of bamboo vascular bundles as well as the through-hole structure are studied. A finite element model validated by the theoretical analysis and drop hammer impact experiments is used to assess the optimal core distribution ratio of the bionic tube at 0°, 10°, 20°, and 30° impacts. Finally the effects of the number of circular core and wall thickness on crashworthiness are investigated. The results show that the bionic tube has better crashworthiness at small angle impacts compared to the square tubes, and l14r6 is obtained as the optimum bionic tube: the SEA at small angles improves by 12.72% (0°), 14.91% (10°), and 18.12% (20°), respectively; however, the SEA at 30° impact decreases by 2.53%. As the number of circular core increases, the crashworthiness becomes more significant, but the deformation mode becomes worse. The SEA of the tube with 32 cores increases by an average of 1.85 times (0°), 1.89 times (10°), 1.34 times (20°), and 1.41 times (30°) for each impact condition, respectively, compared to the tube with single core. [ABSTRACT FROM AUTHOR]

In order to study the influence of different structural forms of counterweight crank on the dynamic balance of crank-group mechanism,the dynamic balance conditions is proposed based on the mass moment substitution method and moment of momentum substitution method and the considering the application of this mechanism in tobacco packaging machine,the three virtual prototyping simulation model of six crank-group mechanism with different structural forms of crank are established. The simulation results show that fan-shaped crank,which has better dynamic balance effect than rectangular crank and triangle crank,is the best suited as the counterweight crank structure. It has important reference value and guiding significance for the design and optimization of physical prototype of crank-group mechanism in the future.