Ballistic experiments were conducted on thin steel plates that are normally impacted by hemisphericalnosed projectiles at velocities higher than their ballistic limits. The deformation and failure modes of the thin st...Ballistic experiments were conducted on thin steel plates that are normally impacted by hemisphericalnosed projectiles at velocities higher than their ballistic limits. The deformation and failure modes of the thin steel plates were analyzed. A new method was proposed according to the experimental results and the perforation phenomenon of the thin steel plates to determine the radius of the bulging region. In establishing this new method, a dynamic method combined with the plastic wave propagation concept based on the rigid plastic assumption was adopted. The whole perforation process was divided into four consecutive stages, namely, bulging deformation, dishing deformation, ductile hole enlargement, and projectile exit. On the basis of the energy conservation principle, a new model was developed to predict the residual velocities of hemispherical-nosed projectiles that perforate thin steel plates at low velocities.The results obtained from the theoretical calculations by the present model were compared with the experimental results. Theoretical predictions were in good agreement with the experimental results in terms of both the radius of the bulging region and the residual velocity of the projectile when the strain rate effects of the target material during each stage were considered.展开更多
Background Massive presacral venous plexus hemorrhage during radical resection of rectal carcinoma is rare, but when it occurs, bleeding can be uncontrollable, leading to death in some cases. Medical adhesive gauze st...Background Massive presacral venous plexus hemorrhage during radical resection of rectal carcinoma is rare, but when it occurs, bleeding can be uncontrollable, leading to death in some cases. Medical adhesive gauze sticking and packing and thumbtack compressive fixation are often used for hemostasis, but these methods are not effective in cases of uncontrollable massive hemorrhage. Therefore, identifying a practical, accurate, and reliable method of hemostasis in these cases is essential.Methods Between January 2004 and December 2009, we treated 3 patients with massive presacral venous plexus hemorrhage during resection of rectal carcinoma by placing small, trimmed thin steel plates at the bleeding sites. The plates were fixed with a saddle-type application of thumbtacks.Results Bleeding was successfully controlled in all 3 patients, and intestinal anastomosis was carried out after hemostasis. No complications were observed.Conclusions Application of a small, thin steel plate to the bleeding site with thumbtack fixation is a simple and effective method of hemostasis in patients with massive presacral venous plexus hemorrhage during resection of rectal carcinoma.展开更多
The loading capacity in the axial direction of a bolted thin steel plate was investigated.A refined numerical model of bolt was first constructed and then validated using existing experiment results.Parametrical analy...The loading capacity in the axial direction of a bolted thin steel plate was investigated.A refined numerical model of bolt was first constructed and then validated using existing experiment results.Parametrical analysis was performed to reveal the influences of geometric parameters,including the effective depth of the cap nut,the yield strength of the steel plate,the preload of the bolt,and shear force,on the ultimate loading capacity.Then,an analytical method was proposed to predict the ultimate load of the bolted thin steel plate.Results derived using the numerical and analytical methods were compared and the results indicated that the analytical method can accurately predict the pull-through capacity of bolted thin steel plates.The work reported in this paper can provide a simplified calculation method for the loading capacity in the axial direction of a bolt.展开更多
Analyzed and studied the characters of high strength low alloy steel which contain Mo,Cr,Nb and Ni.etc.Following actual rolling,combining the feature of rolling mode,and exploiting the equipment advantage of 5 m Heavy...Analyzed and studied the characters of high strength low alloy steel which contain Mo,Cr,Nb and Ni.etc.Following actual rolling,combining the feature of rolling mode,and exploiting the equipment advantage of 5 m Heavy Plate Mill,optimized the material design,heating temperature and rolling method, stabilized rolling process of thin alloyed steel,the quality index was advanced.展开更多
基金financially supported by the National Security Major Foundation Research Project(973)of China(6133050102)the National Natural Science Foundation of China(Grant No.51409253)
文摘Ballistic experiments were conducted on thin steel plates that are normally impacted by hemisphericalnosed projectiles at velocities higher than their ballistic limits. The deformation and failure modes of the thin steel plates were analyzed. A new method was proposed according to the experimental results and the perforation phenomenon of the thin steel plates to determine the radius of the bulging region. In establishing this new method, a dynamic method combined with the plastic wave propagation concept based on the rigid plastic assumption was adopted. The whole perforation process was divided into four consecutive stages, namely, bulging deformation, dishing deformation, ductile hole enlargement, and projectile exit. On the basis of the energy conservation principle, a new model was developed to predict the residual velocities of hemispherical-nosed projectiles that perforate thin steel plates at low velocities.The results obtained from the theoretical calculations by the present model were compared with the experimental results. Theoretical predictions were in good agreement with the experimental results in terms of both the radius of the bulging region and the residual velocity of the projectile when the strain rate effects of the target material during each stage were considered.
文摘Background Massive presacral venous plexus hemorrhage during radical resection of rectal carcinoma is rare, but when it occurs, bleeding can be uncontrollable, leading to death in some cases. Medical adhesive gauze sticking and packing and thumbtack compressive fixation are often used for hemostasis, but these methods are not effective in cases of uncontrollable massive hemorrhage. Therefore, identifying a practical, accurate, and reliable method of hemostasis in these cases is essential.Methods Between January 2004 and December 2009, we treated 3 patients with massive presacral venous plexus hemorrhage during resection of rectal carcinoma by placing small, trimmed thin steel plates at the bleeding sites. The plates were fixed with a saddle-type application of thumbtacks.Results Bleeding was successfully controlled in all 3 patients, and intestinal anastomosis was carried out after hemostasis. No complications were observed.Conclusions Application of a small, thin steel plate to the bleeding site with thumbtack fixation is a simple and effective method of hemostasis in patients with massive presacral venous plexus hemorrhage during resection of rectal carcinoma.
基金The work described in this paper was financially supported by the Project funded by China Postdoctoral Science Foundation(No.2017M621156)the State Key Research Development Program of China(Nos.2016YFC0801404 and 2016YFC0600704).
文摘The loading capacity in the axial direction of a bolted thin steel plate was investigated.A refined numerical model of bolt was first constructed and then validated using existing experiment results.Parametrical analysis was performed to reveal the influences of geometric parameters,including the effective depth of the cap nut,the yield strength of the steel plate,the preload of the bolt,and shear force,on the ultimate loading capacity.Then,an analytical method was proposed to predict the ultimate load of the bolted thin steel plate.Results derived using the numerical and analytical methods were compared and the results indicated that the analytical method can accurately predict the pull-through capacity of bolted thin steel plates.The work reported in this paper can provide a simplified calculation method for the loading capacity in the axial direction of a bolt.
文摘Analyzed and studied the characters of high strength low alloy steel which contain Mo,Cr,Nb and Ni.etc.Following actual rolling,combining the feature of rolling mode,and exploiting the equipment advantage of 5 m Heavy Plate Mill,optimized the material design,heating temperature and rolling method, stabilized rolling process of thin alloyed steel,the quality index was advanced.
