Carbon Fiber Reinforced Thermosetting Composites(CFRTS)are crucial materials for lightweight manufacturing in the aerospace industry.To achieve high-quality butt joining between CFRTS,the Metal-Assistant-Clamping(MAC)...Carbon Fiber Reinforced Thermosetting Composites(CFRTS)are crucial materials for lightweight manufacturing in the aerospace industry.To achieve high-quality butt joining between CFRTS,the Metal-Assistant-Clamping(MAC)laser rotational welding method is proposed.In this method,two TC4 titanium alloy plates were clamped at the docking position of the CFRTS butt joint,and the TC4 titanium alloy plates were joined with the CFRTS using laser rotational welding technology.Laser cleaning and micro-textures as interface pretreatment were applied to enhance the joining strength.The impact of laser cleaning on the strength of the CFRTS butt joint was examined,revealing that epoxy resin on the CFRTS surface was effectively removed,leading to an increase in bonding strength between the CFRTS and TC4 titanium alloy.The microtextures,mechanical properties,and failure mechanism of CFRTS butt joints were investigated.The results indicate that the interface pretreatment created mechanical interlocks and chemical bonds between the CFRTS and TC4 alloy,further strengthening the CFRTS butt joint.The failure of the CFRTS butt joint was observed to occur between the Polyamide-6(PA6)resin and the surface carbon fibers of the CFRTS,predominantly through CFRTS interlayer tearing.展开更多
The dynamic control equation of a new prestressed partially concrete-filled rectangular steel tube(CFRT)beam can be derived based on D’Alembert’s principle.It is used to infer the theoretical results of the dynamic ...The dynamic control equation of a new prestressed partially concrete-filled rectangular steel tube(CFRT)beam can be derived based on D’Alembert’s principle.It is used to infer the theoretical results of the dynamic characteristics for the prestressed CFRT beam.Additionally,the finite element model is set up by ABAQUS for simulation analysis.The results show that the natural vibration frequencies and mode function of the prestressed CFRT simply supported beam calculated by the theoretical formulas are reliable since the relative errors of the first-order frequencies under different prestressing levels are within 6%compared with the finite element results.Further analysis of the prestressing parameters is carried out using the theoretical formulas,in which factors such as the prestressing level,eccentricity of tendons,and tensile stiffness of prestressed tendons have different influences on the natural vibration frequencies.Finally,it provides a theoretical basis for the dynamic design of the prestressed CFRT beams.展开更多
Experimental results of new type joints between the column and the. steel beam of concrete-filled rectangular steel tubular （CFRT） under reversed cyclic loads are presented. The earthquake resistant capacity of the ...Experimental results of new type joints between the column and the. steel beam of concrete-filled rectangular steel tubular （CFRT） under reversed cyclic loads are presented. The earthquake resistant capacity of the joint is influenced by infilled concrete, stiffener length and relative dimensions of column and beam. It is found that the hysteresis curves obtained in the experiment are full and the joints have a good energy dissipation capacity. The nonlinear finite element models are also used to analyze the hysteresis behavior of the joints under reversed cyclic loads using ANSYS 8.0. The influences of the stiffener length and the infilled concrete are analyzed. Analytical results show that the stiffener length and the infilled concrete are critical for the joints. Furthermore, the skeleton curves of the finite element models are in good agreement with those of experiments.展开更多
Objective:The aim of this study was to evaluate the optimal field arrangement for conformal radiotherapy (CFRT) for prostate cancer patients.Methods:Thirty patients with prostate cancer of different grades and stages ...Objective:The aim of this study was to evaluate the optimal field arrangement for conformal radiotherapy (CFRT) for prostate cancer patients.Methods:Thirty patients with prostate cancer of different grades and stages were treated with 3D conformal radiotherapy to minimize the dose to bladder,rectum and head of both femora using four fields (4F),five fields (5F),six fields (6F) and ARC techniques to minimize the risk of over dose to bladder,rectum and femoral heads.Patients received a total dose between 76 to 78 Gy given in 38 to 39 fractions over 7.5 to 8 weeks.Results:It was observed that V95,D95,D50 and D5 values for planning target volume (PTV) were comparatively higher when planned by 5 fields technique than when planned by fixed field technique (91%,91%,90% and 91.4% for skip-scan technique versus 85%,87%,86% and 88% by fixed field).The organs like rectum and urinary bladder get much higher dose when treated by fixed field techniques than rotation or 5 fields technique,when comparison was made for V95,V50 and DM values for rectum and urinary bladder obtained by 5 fields technique planning and 4/6 field planning,the value for 5 fields technique was found to be lower than 4/6 field technique (1%,70% and 51% versus 13%,91% and 55% for rectum and 4%,25% and 51% versus 16%,38% and 56% for urinary bladder respectively).Conclusion:Similarly for femoral heads,planning by full rotational technique had been observed to be beneficial as compared to when planning was done by fixed field technique (0%,0% and 29% versus 0%,1% and 28%).展开更多
基金the financial support by the Ningbo"Science and Technology Innovation Yongjiang 2035"Key Research and Development Program,China(Nos.2025Z188,2025Z016)"The 14th Five Year Plan"Major Technical Research and Development Project of Zhenhai District,China(No.2023001)the CAS Youth Interdisciplinary Team,China(No.2023-135)。
文摘Carbon Fiber Reinforced Thermosetting Composites(CFRTS)are crucial materials for lightweight manufacturing in the aerospace industry.To achieve high-quality butt joining between CFRTS,the Metal-Assistant-Clamping(MAC)laser rotational welding method is proposed.In this method,two TC4 titanium alloy plates were clamped at the docking position of the CFRTS butt joint,and the TC4 titanium alloy plates were joined with the CFRTS using laser rotational welding technology.Laser cleaning and micro-textures as interface pretreatment were applied to enhance the joining strength.The impact of laser cleaning on the strength of the CFRTS butt joint was examined,revealing that epoxy resin on the CFRTS surface was effectively removed,leading to an increase in bonding strength between the CFRTS and TC4 titanium alloy.The microtextures,mechanical properties,and failure mechanism of CFRTS butt joints were investigated.The results indicate that the interface pretreatment created mechanical interlocks and chemical bonds between the CFRTS and TC4 alloy,further strengthening the CFRTS butt joint.The failure of the CFRTS butt joint was observed to occur between the Polyamide-6(PA6)resin and the surface carbon fibers of the CFRTS,predominantly through CFRTS interlayer tearing.
基金the National Natural Science Foundation of China(No.51878407)。
文摘The dynamic control equation of a new prestressed partially concrete-filled rectangular steel tube(CFRT)beam can be derived based on D’Alembert’s principle.It is used to infer the theoretical results of the dynamic characteristics for the prestressed CFRT beam.Additionally,the finite element model is set up by ABAQUS for simulation analysis.The results show that the natural vibration frequencies and mode function of the prestressed CFRT simply supported beam calculated by the theoretical formulas are reliable since the relative errors of the first-order frequencies under different prestressing levels are within 6%compared with the finite element results.Further analysis of the prestressing parameters is carried out using the theoretical formulas,in which factors such as the prestressing level,eccentricity of tendons,and tensile stiffness of prestressed tendons have different influences on the natural vibration frequencies.Finally,it provides a theoretical basis for the dynamic design of the prestressed CFRT beams.
基金Supprorted by the Science and Technology Foundation of Jiangsu Construction Committee(JS200214)the Science Research Foundation of Nanjing Institute of Technology(KXJ08122)~~
文摘Experimental results of new type joints between the column and the. steel beam of concrete-filled rectangular steel tubular （CFRT） under reversed cyclic loads are presented. The earthquake resistant capacity of the joint is influenced by infilled concrete, stiffener length and relative dimensions of column and beam. It is found that the hysteresis curves obtained in the experiment are full and the joints have a good energy dissipation capacity. The nonlinear finite element models are also used to analyze the hysteresis behavior of the joints under reversed cyclic loads using ANSYS 8.0. The influences of the stiffener length and the infilled concrete are analyzed. Analytical results show that the stiffener length and the infilled concrete are critical for the joints. Furthermore, the skeleton curves of the finite element models are in good agreement with those of experiments.
文摘Objective:The aim of this study was to evaluate the optimal field arrangement for conformal radiotherapy (CFRT) for prostate cancer patients.Methods:Thirty patients with prostate cancer of different grades and stages were treated with 3D conformal radiotherapy to minimize the dose to bladder,rectum and head of both femora using four fields (4F),five fields (5F),six fields (6F) and ARC techniques to minimize the risk of over dose to bladder,rectum and femoral heads.Patients received a total dose between 76 to 78 Gy given in 38 to 39 fractions over 7.5 to 8 weeks.Results:It was observed that V95,D95,D50 and D5 values for planning target volume (PTV) were comparatively higher when planned by 5 fields technique than when planned by fixed field technique (91%,91%,90% and 91.4% for skip-scan technique versus 85%,87%,86% and 88% by fixed field).The organs like rectum and urinary bladder get much higher dose when treated by fixed field techniques than rotation or 5 fields technique,when comparison was made for V95,V50 and DM values for rectum and urinary bladder obtained by 5 fields technique planning and 4/6 field planning,the value for 5 fields technique was found to be lower than 4/6 field technique (1%,70% and 51% versus 13%,91% and 55% for rectum and 4%,25% and 51% versus 16%,38% and 56% for urinary bladder respectively).Conclusion:Similarly for femoral heads,planning by full rotational technique had been observed to be beneficial as compared to when planning was done by fixed field technique (0%,0% and 29% versus 0%,1% and 28%).
