Accurate characterization of the mechanical properties of brain tissue is essential for understanding the mechanisms of traumatic brain injuries and developing protective gears or facilities. However, how storage conditions might affect the mechanical properties of brain tissue remains unclear. The objective of this study is to investigate the effect of in vitro storage duration on the mechanical performance of brain tissue since measurements are usually carried out in vitro. Differential Scanning Calorimetry (DSC) measurements and uniaxial compression mechanical experiments are carried out. The results indicate that, for brain tissue stored at 1 °C without any liquid medium, the bio-molecular interactions and the mechanical strength of both white and grey matter deteriorate with prolonged storage duration. Transmission Electron Microscopy (TEM) results reveal the degeneration of myelin sheaths and the vacuolization of cristae with prolonged storage duration, suggesting that the in vitro storage duration should be carefully controlled. The findings from this study might facilitate the development of guidelines and standards for the in vitro storage of brain tissue.

Four kinds of X100 grade pipeline steels containing different chromium content were designed and corrosion behavior were studied in order to confirm the influence of Cr on the properties of high grade pipeline steel. The corrosion experiments demonstrated that Corrosion rates of Four steels in the experiment decrease with the increasing of Cr content, and the scales on the four steels have a two-layer structure under the corrosion of CO2 and H2S. The outer layer is mainly composed of FeS or FeS1-x and the inner layer consisted of FeCO3. Cr enriches in the inner layer and Cr content of the inner layer increases with the Cr content in matrix. The Cr enrichment enhanced the compactness of the scales further hindered the diffusion of ions from liquid to the surface of steel. The corrosion scale with Cr(OH)3 is anion-selective and reduce the amount of anion reaches metal surface, thus reducing corrosion rate.

The tables used in multi-axis numerical control machine need quicker response ability and higher position precision, so their drive motors must have both high torque density and low torque ripple. In order to realize these requirements, based on the characteristics of the oriental silicon steel sheet which is usually used in the transformers, a similar number of poles and slots PM (permanent magnetic) motor with this material is researched and designed. The motor stator is combined with some single tooth which rolling direction is radical. Because of the excellent magnetic performance along the rolling direction, the proposed stator structure can increase the average torque and decrease the torque ripple. In the end, the finite element soft Ansoft is used to prove that the method is correct and effective.