储藏期与储藏压力对稻谷籽粒压缩特性的影响研究

Influence of Storage Pressure and Time on the Compression Characteristic of Paddy Grains

利用质构仪压缩稻谷籽粒的短轴来测定稻谷籽粒的压缩特性。测定的稻谷储藏在不同的时间与压力下。实验结果表明:当储藏时间为60d且储藏压力由0kPa增加到300kPa,稻谷籽粒的破坏力由81.6N减小到73.8N,破坏能由8.10mJ减小到6.27mJ,破坏应变由0.139减小到0.117,表观接触弹性模量由171.3MPa减小到57.7MPa,最大接触应力由40.8MPa减小到19.1MPa。当稻谷储藏压力为77、100、139、200kPa且储藏时间由0~60d,稻谷籽粒的破坏力由81.6N分别减小到79.6、79.1、78.2、77.0N;破坏能由8.10mJ分别减小到7.55、7.35、7.08、6.85mJ;破坏应变由0.139分别减小到0.131、0.128、0.126、0.121;表观接触弹性模量由171.3MPa分别减小到136.0、121.8、110.6、83.3MPa;最大接触应力由41.2MPa分别减小到35.0、32.5、30.3、15.0MPa。结果表明储藏压力与储藏时间对稻谷籽粒的压缩特性有重要的影响。

The compression characteristics of rice grains were measured by compressing short axes of rice grains with a gravimeter.The paddy grains were stored under different pressures and for different time.The results showed that as the storage pressure increased from 0 to 300 kPa,the rupture force of paddy grains stored for 60 decreased from 81.6 to 73.8 N,the rupture energy from 8.10 to 6.27 mJ,the rupture strain from 0.139 to 0.117,the apparent contact modulus of elasticity from 171.3 to 57.7 MPa and the maximum contact stress from 40.8 to 19.1 MPa.All of the compression characteristic of the paddy grains exhibited a linear relationship with storage pressure.As for the paddy grains stored under the pressures of 77,100,139,200 kPa,as the storage time increased from 0 to 60 days,the rupture force of the paddy grains declined from 81.6 to 79.6 N,81.6 to 79.1 N,81.6 to 78.2 N and 81.6 to 77.0 N;the rupture energy fell from 8.10 to 7.55 mJ,8.10 to 7.35 mJ,8.10 to 7.08 mJ and 8.10 to 6.85 mJ;the rupture strain decreased from 0.139 to 0.131,0.139 to 0.128,0.139 to 0.126 and 0.139 to 0.121;the apparent contact modulus of elasticity fell from 171.3 to 136.0 MPa,171.3 to 121.8 MPa,171.3 to 110.6 MPa and 171.3 to 83.3 MPa;the maximum contact stress decreased from 41.2 to 35.0 MPa,41.2 to 32.5 MPa,41.2 to 30.3 MPa and 41.2 to 15.0 MPa,respectively.The results revealed that both storage pressure and storage time have a significant influence on the compression characteristics of paddy grains.