In this study,the characteristics of heat transfer on an unsteady magnetohydrodynamic(MHD)Casson nanofluid over an exponentially accelerated vertical porous plate with rotating effects were investigated.The flow was d...In this study,the characteristics of heat transfer on an unsteady magnetohydrodynamic(MHD)Casson nanofluid over an exponentially accelerated vertical porous plate with rotating effects were investigated.The flow was driven by the combined effects of the magnetic field,heat radiation,heat source/sink and chemical reaction.Copper oxide(CuO)and titanium oxide(TiO2)are acknowledged as nanoparticle materials.The nondimensional governing equations were subjected to the Laplace transformation technique to derive closed-form solutions.Graphical representations are provided to analyze how changes in physical parameters,such as the magnetic field,heat radiation,heat source/sink and chemical reaction,affect the velocity,temperature and concentration profiles.The computed values of skin friction,heat and mass transfer rates at the surface were tabulated for various sets of input parameters.It is perceived that there is a drop in temperature due to the rise in the heat source/sink and the Prandtl number.It should be noted that a boost in the thermal radiation parameter prompts an increase in temperature.An increase in the Prandtl number,heat source/sink parameter,time and a decrease in the thermal radiation parameter result in an increase in theNusselt number.The computed values of the skin friction,heat andmass transfer rates at the surface were tabulated for various values of the flow parameters.The present results were compared with those of previously published studies andwere found to be in excellent agreement.This research has practical applications in areas such as drug delivery,thermal medicine and cancer treatment.展开更多
Objective:To observe the clinical effect of anterior decompression and reconstruction using titanium mesh with locking plates in the treatment of cervical spondylotic myelopathy. Methods:One hundred and twenty patie...Objective:To observe the clinical effect of anterior decompression and reconstruction using titanium mesh with locking plates in the treatment of cervical spondylotic myelopathy. Methods:One hundred and twenty patients with cervical spondylotic myelopathy were treated by anterior decompression and reconstruction using titanium mesh with locking plates. There were 66 men and 54 women ranges in age from 37 to 72 Years(mean age, 58.3 years). The mean Japanese orthopedic surgery association(JOA) scale was 9.6 points before operation. Patients were followed up clinically and radiographically. Results:Having stood surgery well, the operation time ranged between 60-100 min and bleeding during operation ranged between 20-200 ml. There were no case of postoperative infection, recurrent laryngeal nerve palsy, or esophageal or tracheal laceration or rupture. The average follow-up period was 14.3 months(range, 12 to 24 months) in 96 who were followed up. At the last follow-up visit the mean JOA scale had improved to 14.4 points, reflecting an improvement of 4.8 points. The results were considered to be excellent in 87 patients, good in 25, fair in 6, and poor in 2. No hardware-related complications or adjacent segment degenerative changes were encountered during the follow-up periods. Stable bone union was observed in all cases and the average time required for fusion was 5.7 months. Conclusion:Titanium mesh filled with autologous bone graft can avoid the complications associated with harvesting bone from the iliac crest donor site. When combined with cervical anterior locking plate, it can obtain satisfatory clinical results for the treatment of cervical spondylotic myelopathy.展开更多
In this study,the interface characteristics of a direct hot rolling titanium-clad steel plate were analyzed, and the mechanism of interface cracking was explored. The detrimental effect from the formation of TiFe ,TiC...In this study,the interface characteristics of a direct hot rolling titanium-clad steel plate were analyzed, and the mechanism of interface cracking was explored. The detrimental effect from the formation of TiFe ,TiC,and a Si-enriched layer on the bonding strength was clarified, and an industrial-scaled titanium-clad steel plate with shear strength over 200 MPa was produced with a carefully set schedule accordingly. It was found that hot rolling titanium-clad steel plates had a flat interface without obvious cracks. In the rolling process,both Ti and Fe atoms interdiflhsed,but Fe difthsed much faster than Ti. The Fe-diffused area consisted of three regions. After a high temperature heat treatment, the diffusion depth of Fe and Ti elements increased significantly and evident Si segregation and TiFe layers were identified. Thermal cracking initiated in the Si segregation layer and then propagated along the TiFe layer and Fe-diffused layer on the titanium side.展开更多
The low cycle fatigue behavior of zirconium−titanium−steel composite plate under symmetrical and asymmetric stress control was studied.The effects of mean stress and stress amplitude on cyclic deformation,ratcheting e...The low cycle fatigue behavior of zirconium−titanium−steel composite plate under symmetrical and asymmetric stress control was studied.The effects of mean stress and stress amplitude on cyclic deformation,ratcheting effect and damage mechanism were discussed in detail.The results show that under symmetric stress control,the forward ratcheting deformation is observed.Under asymmetric stress control,the ratcheting strain increases rapidly with mean stress and stress amplitude increasing.Under high stress amplitude,the influence of mean stress is more significant.In addition,by studying the variation of strain energy density,it is found that the stress amplitude mainly promotes the fatigue damage,while the mean stress leads to the ratcheting damage.In addition,fractographic observation shows that the crack initiates in the brittle metal compound at the interface,and the steel has higher resistance to crack propagation.Finally,the accuracy of life prediction model considering ratcheting effect is discussed in detail,and a high-precision life prediction model directly based on mean stress and stress amplitude is proposed.展开更多
Objective To compare the clinical effects of treating cervical prolapse of intervertebral disc by using Solis cage, titanium cage and autogenous iliac crest graft (AICG) combined with titanium plate. Methods 64 cases ...Objective To compare the clinical effects of treating cervical prolapse of intervertebral disc by using Solis cage, titanium cage and autogenous iliac crest graft (AICG) combined with titanium plate. Methods 64 cases of cervical prolapse of intervertebral disc were analyzed retrospectively. All the patients were followed up for about one year. Group A is composed of 20 patients (30 intervertebral spaces) treated with microdiscectomy and Solis cage fusion; group B is composed of 21 patients(22 intervertebral spaces) treated with titanium cage and group C is involved of 23 patients(28 intervertebral spaces) which were dealt with AICG combined with titanium plate. The differences in the total X ray exposure time, time working on iliac bone, incidence of complications, fusion rate, incidence of JOA score recovery rate more than 50% and rehabilitation time of the three groups are analyzed. Results All indexes from group A and B were more satisfactory than those from group C (P<0.05). The statistic analysis results of the incidence of complications of cervical part, rehabilitation time in group A are 5.0±1.8, 5.1±1.2; and that is 14.3±2.6, 7.5 ±1.6 and 26.1±6.2, 8.6±2.3 in group B and group C respectively. There is significant difference between group A and group B on the incidence of complications of cervical part and rehabilitation time (P<0.05). Results of the incidence of JOA score recovery rate >50% in group A(95.8±3.2) was more satisfactory than that in group B(93.6±2.9), while there was no statistical difference between group A and group B (P>0.05). Conclusion The Solis cage is better in treating the cervical prolapse of intervertebral disc than other ways. Also, it makes the operation easier, rehabilitation time shorter, and it causes fewer complications.展开更多
Chest wall reconstruction after en-bloc tumor resection is very important to preserve functional mobility and to enhance the cosmetic effect. Because they are flexible and pliable, titanium plates are proposed to reco...Chest wall reconstruction after en-bloc tumor resection is very important to preserve functional mobility and to enhance the cosmetic effect. Because they are flexible and pliable, titanium plates are proposed to reconstruct the chest wall, even though such chest wall reconstruction has been performed in only a few cases worldwide. We present a case of a 49-year-old man with a chondrosarcoma arising from the left 1st rib, invading the manubrium, clavicle, 2nd and 3rd ribs, and the anterior segment of the left upper lobe. After wide resection, the chest wall was reconstructed using titanium rib plates and Marlex mesh- the Bovine pericardium sandwich type. The patient tolerated the pain well, and fourteen months after surgery, the chest wall was well preserved function mobility and improved pulmonary function test.展开更多
The scanning electron microscope (SEM) results of bone interface of titanium-coated 317L plate screw are reported in this article. 317L plate screw had a rough surface composed of sprayed pure titanium which formed a ...The scanning electron microscope (SEM) results of bone interface of titanium-coated 317L plate screw are reported in this article. 317L plate screw had a rough surface composed of sprayed pure titanium which formed a bone/metal interface in biointegration after implanted into the mandible of dog. Though a bone/metal interface in osseointegration was also formed on the surface of uncoated 317L plate screw after implantation, a smal1 space was seen between the bone and surface of the screw, indicating that the tissue compatibility of titanium-coated 317L plate screw may be better than that of the non-coated screw.展开更多
文摘In this study,the characteristics of heat transfer on an unsteady magnetohydrodynamic(MHD)Casson nanofluid over an exponentially accelerated vertical porous plate with rotating effects were investigated.The flow was driven by the combined effects of the magnetic field,heat radiation,heat source/sink and chemical reaction.Copper oxide(CuO)and titanium oxide(TiO2)are acknowledged as nanoparticle materials.The nondimensional governing equations were subjected to the Laplace transformation technique to derive closed-form solutions.Graphical representations are provided to analyze how changes in physical parameters,such as the magnetic field,heat radiation,heat source/sink and chemical reaction,affect the velocity,temperature and concentration profiles.The computed values of skin friction,heat and mass transfer rates at the surface were tabulated for various sets of input parameters.It is perceived that there is a drop in temperature due to the rise in the heat source/sink and the Prandtl number.It should be noted that a boost in the thermal radiation parameter prompts an increase in temperature.An increase in the Prandtl number,heat source/sink parameter,time and a decrease in the thermal radiation parameter result in an increase in theNusselt number.The computed values of the skin friction,heat andmass transfer rates at the surface were tabulated for various values of the flow parameters.The present results were compared with those of previously published studies andwere found to be in excellent agreement.This research has practical applications in areas such as drug delivery,thermal medicine and cancer treatment.
文摘Objective:To observe the clinical effect of anterior decompression and reconstruction using titanium mesh with locking plates in the treatment of cervical spondylotic myelopathy. Methods:One hundred and twenty patients with cervical spondylotic myelopathy were treated by anterior decompression and reconstruction using titanium mesh with locking plates. There were 66 men and 54 women ranges in age from 37 to 72 Years(mean age, 58.3 years). The mean Japanese orthopedic surgery association(JOA) scale was 9.6 points before operation. Patients were followed up clinically and radiographically. Results:Having stood surgery well, the operation time ranged between 60-100 min and bleeding during operation ranged between 20-200 ml. There were no case of postoperative infection, recurrent laryngeal nerve palsy, or esophageal or tracheal laceration or rupture. The average follow-up period was 14.3 months(range, 12 to 24 months) in 96 who were followed up. At the last follow-up visit the mean JOA scale had improved to 14.4 points, reflecting an improvement of 4.8 points. The results were considered to be excellent in 87 patients, good in 25, fair in 6, and poor in 2. No hardware-related complications or adjacent segment degenerative changes were encountered during the follow-up periods. Stable bone union was observed in all cases and the average time required for fusion was 5.7 months. Conclusion:Titanium mesh filled with autologous bone graft can avoid the complications associated with harvesting bone from the iliac crest donor site. When combined with cervical anterior locking plate, it can obtain satisfatory clinical results for the treatment of cervical spondylotic myelopathy.
文摘In this study,the interface characteristics of a direct hot rolling titanium-clad steel plate were analyzed, and the mechanism of interface cracking was explored. The detrimental effect from the formation of TiFe ,TiC,and a Si-enriched layer on the bonding strength was clarified, and an industrial-scaled titanium-clad steel plate with shear strength over 200 MPa was produced with a carefully set schedule accordingly. It was found that hot rolling titanium-clad steel plates had a flat interface without obvious cracks. In the rolling process,both Ti and Fe atoms interdiflhsed,but Fe difthsed much faster than Ti. The Fe-diffused area consisted of three regions. After a high temperature heat treatment, the diffusion depth of Fe and Ti elements increased significantly and evident Si segregation and TiFe layers were identified. Thermal cracking initiated in the Si segregation layer and then propagated along the TiFe layer and Fe-diffused layer on the titanium side.
基金the financial support from the National Natural Science Foundation of China(Nos.51975271,51675260,51475223)the Starting Research Fund of Nanjing Vocational University of Industry Technology,China(No.YK20-14-05)。
文摘The low cycle fatigue behavior of zirconium−titanium−steel composite plate under symmetrical and asymmetric stress control was studied.The effects of mean stress and stress amplitude on cyclic deformation,ratcheting effect and damage mechanism were discussed in detail.The results show that under symmetric stress control,the forward ratcheting deformation is observed.Under asymmetric stress control,the ratcheting strain increases rapidly with mean stress and stress amplitude increasing.Under high stress amplitude,the influence of mean stress is more significant.In addition,by studying the variation of strain energy density,it is found that the stress amplitude mainly promotes the fatigue damage,while the mean stress leads to the ratcheting damage.In addition,fractographic observation shows that the crack initiates in the brittle metal compound at the interface,and the steel has higher resistance to crack propagation.Finally,the accuracy of life prediction model considering ratcheting effect is discussed in detail,and a high-precision life prediction model directly based on mean stress and stress amplitude is proposed.
文摘Objective To compare the clinical effects of treating cervical prolapse of intervertebral disc by using Solis cage, titanium cage and autogenous iliac crest graft (AICG) combined with titanium plate. Methods 64 cases of cervical prolapse of intervertebral disc were analyzed retrospectively. All the patients were followed up for about one year. Group A is composed of 20 patients (30 intervertebral spaces) treated with microdiscectomy and Solis cage fusion; group B is composed of 21 patients(22 intervertebral spaces) treated with titanium cage and group C is involved of 23 patients(28 intervertebral spaces) which were dealt with AICG combined with titanium plate. The differences in the total X ray exposure time, time working on iliac bone, incidence of complications, fusion rate, incidence of JOA score recovery rate more than 50% and rehabilitation time of the three groups are analyzed. Results All indexes from group A and B were more satisfactory than those from group C (P<0.05). The statistic analysis results of the incidence of complications of cervical part, rehabilitation time in group A are 5.0±1.8, 5.1±1.2; and that is 14.3±2.6, 7.5 ±1.6 and 26.1±6.2, 8.6±2.3 in group B and group C respectively. There is significant difference between group A and group B on the incidence of complications of cervical part and rehabilitation time (P<0.05). Results of the incidence of JOA score recovery rate >50% in group A(95.8±3.2) was more satisfactory than that in group B(93.6±2.9), while there was no statistical difference between group A and group B (P>0.05). Conclusion The Solis cage is better in treating the cervical prolapse of intervertebral disc than other ways. Also, it makes the operation easier, rehabilitation time shorter, and it causes fewer complications.
文摘Chest wall reconstruction after en-bloc tumor resection is very important to preserve functional mobility and to enhance the cosmetic effect. Because they are flexible and pliable, titanium plates are proposed to reconstruct the chest wall, even though such chest wall reconstruction has been performed in only a few cases worldwide. We present a case of a 49-year-old man with a chondrosarcoma arising from the left 1st rib, invading the manubrium, clavicle, 2nd and 3rd ribs, and the anterior segment of the left upper lobe. After wide resection, the chest wall was reconstructed using titanium rib plates and Marlex mesh- the Bovine pericardium sandwich type. The patient tolerated the pain well, and fourteen months after surgery, the chest wall was well preserved function mobility and improved pulmonary function test.
文摘The scanning electron microscope (SEM) results of bone interface of titanium-coated 317L plate screw are reported in this article. 317L plate screw had a rough surface composed of sprayed pure titanium which formed a bone/metal interface in biointegration after implanted into the mandible of dog. Though a bone/metal interface in osseointegration was also formed on the surface of uncoated 317L plate screw after implantation, a smal1 space was seen between the bone and surface of the screw, indicating that the tissue compatibility of titanium-coated 317L plate screw may be better than that of the non-coated screw.