In the present study,three layers of aluminum(Al)and a single layer of copper(Cu)were joined by resistance rolling welding(RRW)and the impact of welding velocity on microstructure,mechanical property and electrical pr...In the present study,three layers of aluminum(Al)and a single layer of copper(Cu)were joined by resistance rolling welding(RRW)and the impact of welding velocity on microstructure,mechanical property and electrical property was investigated.The results showed that the welding velocity was identified as the most significant parameter.With decreasing the welding velocity from 11 mm/s to 1 mm/s,the mechanical property of the joints initially showed an increase,reaching a maximum coach-peel peak load of 185.25 N,due to the larger well bonded region,then decreased owing to the high-temperature softening of the base metal.The elec-trical resistance of the joint demonstrated a consistent varying,characterized by an initial decrease owing to the larger completely bonded region and then increased with the decreasing welding velocity due to the excessive generation of Al2Cu with high electrical resistance.A cooling system was thus utilized to reduce the welding temperature to relieve the high-temperature softening,that suc-cessfully improved the welding quality of the joint by an 11.5%increase in the coach-peel peak load.展开更多
The effect of soil nutrient content on fruit yield and fruit quality is very important.To explore the effect of soil nutrients on apple quality we investigated 200 fruit samples from 40 orchards in Feng County,Jiangsu...The effect of soil nutrient content on fruit yield and fruit quality is very important.To explore the effect of soil nutrients on apple quality we investigated 200 fruit samples from 40 orchards in Feng County,Jiangsu Province.Soil mineral elements and fruit quality were measured.The effect of soil nutrient content on fruit quality was analyzed by artificial neural network(ANN)model.The results showed that the prediction accuracy was highest(R2=0.851,0.847,0.885,0.678 and 0.746)in mass per fruit(MPF),hardness(HB),soluble solids concentrations(SSC),titratable acid concentration(TA)and solid-acid ratio(SSC/TA),respectively.The sensitivity analysis of the prediction model showed that soil available P,K,Ca and Mg contents had the greatest impact on the quality of apple fruit.Response surface method(RSM)was performed to determine the optimum range of the available P,K,Ca,and Mg contents in orchards In Feng County,which were 10∼20 mg⋅kg^(−1),170∼200 mg⋅kg^(−1),1000∼1500 mg⋅kg^(−1),and 80∼200 mg⋅kg^(−1),respectively.The research also concluded that improving the content of available P and available Ca in orchard soil was crucial to improve apple fruit quality in Feng County,Jiangsu Province.展开更多
基金supported by the National Key Research and Development Program of China(Grant No.2023YFB3407400)the National Natural Science Foundation of China(Grant No.52475386,Grant No.52025058).
文摘In the present study,three layers of aluminum(Al)and a single layer of copper(Cu)were joined by resistance rolling welding(RRW)and the impact of welding velocity on microstructure,mechanical property and electrical property was investigated.The results showed that the welding velocity was identified as the most significant parameter.With decreasing the welding velocity from 11 mm/s to 1 mm/s,the mechanical property of the joints initially showed an increase,reaching a maximum coach-peel peak load of 185.25 N,due to the larger well bonded region,then decreased owing to the high-temperature softening of the base metal.The elec-trical resistance of the joint demonstrated a consistent varying,characterized by an initial decrease owing to the larger completely bonded region and then increased with the decreasing welding velocity due to the excessive generation of Al2Cu with high electrical resistance.A cooling system was thus utilized to reduce the welding temperature to relieve the high-temperature softening,that suc-cessfully improved the welding quality of the joint by an 11.5%increase in the coach-peel peak load.
基金supported by the National Key Research and Development Program of China(2019YFD1000103)National Natural Science Foundation of China(31872076)+1 种基金supported by the National Key Research and Development Program of China(2019YFD1000103)National Natural Science Foundation of China(31872076).
文摘The effect of soil nutrient content on fruit yield and fruit quality is very important.To explore the effect of soil nutrients on apple quality we investigated 200 fruit samples from 40 orchards in Feng County,Jiangsu Province.Soil mineral elements and fruit quality were measured.The effect of soil nutrient content on fruit quality was analyzed by artificial neural network(ANN)model.The results showed that the prediction accuracy was highest(R2=0.851,0.847,0.885,0.678 and 0.746)in mass per fruit(MPF),hardness(HB),soluble solids concentrations(SSC),titratable acid concentration(TA)and solid-acid ratio(SSC/TA),respectively.The sensitivity analysis of the prediction model showed that soil available P,K,Ca and Mg contents had the greatest impact on the quality of apple fruit.Response surface method(RSM)was performed to determine the optimum range of the available P,K,Ca,and Mg contents in orchards In Feng County,which were 10∼20 mg⋅kg^(−1),170∼200 mg⋅kg^(−1),1000∼1500 mg⋅kg^(−1),and 80∼200 mg⋅kg^(−1),respectively.The research also concluded that improving the content of available P and available Ca in orchard soil was crucial to improve apple fruit quality in Feng County,Jiangsu Province.