Alternate wetting and drying irrigation(AWD)significantly influences the cooking and eating quality of rice(Oryza sativa L.).However,the mechanisms by which AWD affects rice cooking and eating quality remain unclear.L...Alternate wetting and drying irrigation(AWD)significantly influences the cooking and eating quality of rice(Oryza sativa L.).However,the mechanisms by which AWD affects rice cooking and eating quality remain unclear.Lipid and free fatty acid contents in grains correlate positively with cooking and eating quality of rice.This study examined Yangdao 6(YD6,a conventional taste indica inbred)and Nanjing 9108(NJ9108,a superior taste japonica inbred)cultivated under conventional irrigation(CI),alternate wetting and moderate drying irrigation(AWMD),and alternate wetting and severe drying irrigation(AWSD)from 10 days after transplanting to maturity.The research investigated the relationship between lipid and free fatty acid biosynthesis in grains and the cooking and eating quality of rice.Compared to CI treatment,AWMD significantly enhanced the contents of lipid,total free fatty acids(TFFAs),free unsaturated fatty acids(FUFAs),linoleic acid,and oleic acid in milled rice by increasing activities of enzymes associated with lipid synthesis,while AWSD produced opposite effects.Correlation analysis revealed that elevated levels of lipid,TFFAs,FUFAs,linoleic acid,and oleic acid contribute to improved rice cooking and eating quality.The findings demonstrate that AWMD enhances cooking and eating quality of milled rice through optimization of lipid and fatty acid synthesis in rice grains.展开更多
为研究一种高强钢的静动态力学特性并构建Johnson-Cook本构模型,利用电子万能试验机进行了准静态压缩和拉伸试验,获取了材料在室温准静态条件下的应力-应变曲线、弹性模量和泊松比。通过分离式霍普金森压杆,在293~1073 K 5种温度和800~2...为研究一种高强钢的静动态力学特性并构建Johnson-Cook本构模型,利用电子万能试验机进行了准静态压缩和拉伸试验,获取了材料在室温准静态条件下的应力-应变曲线、弹性模量和泊松比。通过分离式霍普金森压杆,在293~1073 K 5种温度和800~2100 s^(-1)4种应变率下开展动态压缩试验,获得了材料在不同条件下的动态应力-应变曲线。最后,基于试验数据构建其Johnson-Cook本构模型,并对模型的准确性进行验证。结果表明:材料的屈服应力随着应变率的增加而增加,但增长幅度较小,应变率强化效应不显著;当应变率为1000 s^(-1)时,材料的屈服应力随温度升高而显著降低。通过本构模型计算得到的应力-应变曲线与试验结果吻合良好,表明模型能够较准确地预测材料的应力行为。展开更多
基金supported by the Natural Science Foundation of Jiangsu Province,China(BK20241931 and BK 20221371)the National Natural Science Foundation of China(32071943,32372214,and 31901444)the National Key Research and Development Program of China(2022YFD2300304)。
文摘Alternate wetting and drying irrigation(AWD)significantly influences the cooking and eating quality of rice(Oryza sativa L.).However,the mechanisms by which AWD affects rice cooking and eating quality remain unclear.Lipid and free fatty acid contents in grains correlate positively with cooking and eating quality of rice.This study examined Yangdao 6(YD6,a conventional taste indica inbred)and Nanjing 9108(NJ9108,a superior taste japonica inbred)cultivated under conventional irrigation(CI),alternate wetting and moderate drying irrigation(AWMD),and alternate wetting and severe drying irrigation(AWSD)from 10 days after transplanting to maturity.The research investigated the relationship between lipid and free fatty acid biosynthesis in grains and the cooking and eating quality of rice.Compared to CI treatment,AWMD significantly enhanced the contents of lipid,total free fatty acids(TFFAs),free unsaturated fatty acids(FUFAs),linoleic acid,and oleic acid in milled rice by increasing activities of enzymes associated with lipid synthesis,while AWSD produced opposite effects.Correlation analysis revealed that elevated levels of lipid,TFFAs,FUFAs,linoleic acid,and oleic acid contribute to improved rice cooking and eating quality.The findings demonstrate that AWMD enhances cooking and eating quality of milled rice through optimization of lipid and fatty acid synthesis in rice grains.
文摘为研究一种高强钢的静动态力学特性并构建Johnson-Cook本构模型,利用电子万能试验机进行了准静态压缩和拉伸试验,获取了材料在室温准静态条件下的应力-应变曲线、弹性模量和泊松比。通过分离式霍普金森压杆,在293~1073 K 5种温度和800~2100 s^(-1)4种应变率下开展动态压缩试验,获得了材料在不同条件下的动态应力-应变曲线。最后,基于试验数据构建其Johnson-Cook本构模型,并对模型的准确性进行验证。结果表明:材料的屈服应力随着应变率的增加而增加,但增长幅度较小,应变率强化效应不显著;当应变率为1000 s^(-1)时,材料的屈服应力随温度升高而显著降低。通过本构模型计算得到的应力-应变曲线与试验结果吻合良好,表明模型能够较准确地预测材料的应力行为。
