This paper studied the index system of ecological balanced fertilization for maize by data mining method based on data of"3414 fertilizer field trials"of maize by published papers from national soil testing ...This paper studied the index system of ecological balanced fertilization for maize by data mining method based on data of"3414 fertilizer field trials"of maize by published papers from national soil testing and recommendation since 2005.The results and conclusions were as follows.①Soil nutrient content could not be used as indicator of fertilizer application of maize.②The conceptual model of N conversion rate of maize for plot was Y N≈a+b×optimum production-c×optimum fertilizer amount of N-d×optimum phosphorus application amount-e×optimum potassium application amount-f×temperature in growth season-g×rainfall in growth season.The conceptual model of P conversion rate of maize for plot was Y P≈a+b×optimum phosphorus application amount-c×optimum nitrogen application amount-d×optimum potassium application amount.The conceptual model of K conversion rate of maize for plot was Y K≈a+b×optimum yield-c×optimum nitrogen application amount-d×optimum phosphorus application amount-e×optimum potassium application amount-f×temperature in growth season-g×rainfall in growth season.③The conceptual model of the optimum fertilizer amount of N of maize for plot was Y N≈a+b×optimum phosphorus application amount+c×optimum potassium application amount+d×temperature in growing season+e×rainfall in growing season,and the conceptual model of the optimum fertilizer amount of P was Y P≈a+b×optimum nitrogen application amount,and the conceptual model of the optimum fertilizer amount of K was Y K≈a+b×optimum nitrogen application amount+c×temperature in growth season+d×rainfall in growth season-e×optimum yield.④The conceptual model of relative abundance-deficiency value of soil N of maize for plot was that Y N≈a,and the conceptual model of relative abundance-deficiency value of soil P was Y P≈a,and the conceptual model of relative abundance-deficiency value of soil K was Y K≈a+b×optimum nitrogen application amount+c×optimum phosphorus application amount.展开更多
Oil storage in cavern tank is one of the important ways of oil storage.More than 80%of the oil tanks in the cave storage have been used for around 30 years in China and leakage accidents are likely to occur.When it oc...Oil storage in cavern tank is one of the important ways of oil storage.More than 80%of the oil tanks in the cave storage have been used for around 30 years in China and leakage accidents are likely to occur.When it occurs,the motor closing facilities preventing leakage spreading should be set up.The leaking oil flow characteristic in tunnel must be known for setting up the motor closing facilities.Based on the open-channel unsteady flow theory,a numerical model of tank leakage coupling the oil flow in tunnel was developed,and the characteristic line method was used to solve the model under the given initial condition and boundary condition.The variation of the depth and flow rate with time of oil flowing in the tunnel can be obtained.In order to verify the accuracy of model,the measurement data of high accuracy experimental system for unsteady open-channel flow were conducted to compare with the calculation.It fully confirms the high precision of the numerical model and reflects the variation characteristics of each hydraulic parameter in the numerical model of unsteady open channel flow truly.And then,the leaking oil flow characteristic in tunnel was obtained.It is that the farther from the leaking tank,the lower depth and flow rate of the oil in the tunnel revealed.Furthermore,the effect of the size of oil tank crack on the depth and flow rate was investigated.The greater size of crack makes the oil flow rate higher and the oil deeper in the tunnel and flow faster.展开更多
基金Major Scientific and Technological Projects in Guangxi(GUIKE AA17204077)Special Project of Guangxi Science and Technology Base and Talent(GUIKE AD18126012)+2 种基金First-class Discipline(Geography)Construction Project in GuangxiSpecial Funds for"Guangxi Bagui Scholars"Collaborative Innovation Task of Science and Technology Innovation Project of Chinese Academy of Agricultural Sciences—Integration and Demonstration of Green and Efficient Agricultural Technology Innovation in Danjiangkou Water Conservation Area(CAAS-XTCX2016015).
文摘This paper studied the index system of ecological balanced fertilization for maize by data mining method based on data of"3414 fertilizer field trials"of maize by published papers from national soil testing and recommendation since 2005.The results and conclusions were as follows.①Soil nutrient content could not be used as indicator of fertilizer application of maize.②The conceptual model of N conversion rate of maize for plot was Y N≈a+b×optimum production-c×optimum fertilizer amount of N-d×optimum phosphorus application amount-e×optimum potassium application amount-f×temperature in growth season-g×rainfall in growth season.The conceptual model of P conversion rate of maize for plot was Y P≈a+b×optimum phosphorus application amount-c×optimum nitrogen application amount-d×optimum potassium application amount.The conceptual model of K conversion rate of maize for plot was Y K≈a+b×optimum yield-c×optimum nitrogen application amount-d×optimum phosphorus application amount-e×optimum potassium application amount-f×temperature in growth season-g×rainfall in growth season.③The conceptual model of the optimum fertilizer amount of N of maize for plot was Y N≈a+b×optimum phosphorus application amount+c×optimum potassium application amount+d×temperature in growing season+e×rainfall in growing season,and the conceptual model of the optimum fertilizer amount of P was Y P≈a+b×optimum nitrogen application amount,and the conceptual model of the optimum fertilizer amount of K was Y K≈a+b×optimum nitrogen application amount+c×temperature in growth season+d×rainfall in growth season-e×optimum yield.④The conceptual model of relative abundance-deficiency value of soil N of maize for plot was that Y N≈a,and the conceptual model of relative abundance-deficiency value of soil P was Y P≈a,and the conceptual model of relative abundance-deficiency value of soil K was Y K≈a+b×optimum nitrogen application amount+c×optimum phosphorus application amount.
基金by Natural Science Foundation of Chongqing(cstc2019jcyj-msxmX0268,cstc2019jcyjmsxmX0286 and cstc2019jcyj-msxmX0628).
文摘Oil storage in cavern tank is one of the important ways of oil storage.More than 80%of the oil tanks in the cave storage have been used for around 30 years in China and leakage accidents are likely to occur.When it occurs,the motor closing facilities preventing leakage spreading should be set up.The leaking oil flow characteristic in tunnel must be known for setting up the motor closing facilities.Based on the open-channel unsteady flow theory,a numerical model of tank leakage coupling the oil flow in tunnel was developed,and the characteristic line method was used to solve the model under the given initial condition and boundary condition.The variation of the depth and flow rate with time of oil flowing in the tunnel can be obtained.In order to verify the accuracy of model,the measurement data of high accuracy experimental system for unsteady open-channel flow were conducted to compare with the calculation.It fully confirms the high precision of the numerical model and reflects the variation characteristics of each hydraulic parameter in the numerical model of unsteady open channel flow truly.And then,the leaking oil flow characteristic in tunnel was obtained.It is that the farther from the leaking tank,the lower depth and flow rate of the oil in the tunnel revealed.Furthermore,the effect of the size of oil tank crack on the depth and flow rate was investigated.The greater size of crack makes the oil flow rate higher and the oil deeper in the tunnel and flow faster.
