Estimating EC and ionic EC contribution percentage of nutrient solution based on ionic activity
作者机构:Key Laboratory of Agriculture Engineering in Structure and Environment of Ministry of Agriculture and Rural AffairChina Agricultural UniversityBeijing 100083China Chiba UniversityKashiwaChiba 277-0882Japan Japan Plant Factory AssociationKashiwaChiba 277-0882Japan
出 版 物:《International Journal of Agricultural and Biological Engineering》 (国际农业与生物工程学报(英文))
年 卷 期:2019年第12卷第2期
页 面:42-48页
核心收录:
学科分类:0710[理学-生物学] 0810[工学-信息与通信工程] 07[理学] 0805[工学-材料科学与工程(可授工学、理学学位)] 0701[理学-数学] 0812[工学-计算机科学与技术(可授工学、理学学位)] 070101[理学-基础数学]
主 题:hydroponics nutrient solution ionic activity soilless culture Debye-Hückel limiting equation ionic EC contribution percentage nutrient formula solution dynamic control
摘 要:The dynamic monitoring technology of inorganic ions using ion selective electrodes has some problems such as low precision,vulnerability to other ions,short service life,and high *** to the difficulty of dynamic control based on ionic concentration of nutrient solution,EC and pH values of nutrient solution are often used as feedback control indexes in hydroponic *** this study,estimation algorisms of EC and ionic EC contribution percentage based on ionic activity were proposed to understand the quantitative relationship between ionic concentration and *** a view to predicting the EC accurately by mean ionic activities of specific salts in nutrient solution based on a specific formula,ionic concentration could also be calculated by the actual measurement of EC combined with ionic EC contribution *** Japanese horticultural experimental nutrient formula and Yamasaki tomato nutrient formula,significant linear correlations between estimated EC and measured EC were found with determination coefficients over *** EC contribution percentage was not affected by different relative concentrations of nutrient ***,ionic EC contribution percentage changed significantly when adding specific salts with different concentrations,and different changes were found in each anions and cations of specific salt *** the same K+concentration was added in different forms of KNO_(3),K_(2_SO_(4),KCl,and KH_(2)PO_(4),the changes of ionic EC contribution percentage of K^(+)were similar,but those of other anions in potassium salts varied *** relative errors of estimated EC of nutrient solutions based on ionic activities were only 1.3%in horticultural experimental nutrient solution and 1.8%in Yamasaki tomato nutrient solution with different relative concentrations compared to measured *** relative errors of estimated EC of nutrient solutions with specific salt added were only 0.1%-0.5%compared to measured EC in two nutrient solution.T