Evaluation on Ideal Test Sites and Regional Characteristics of Cotton Fiber Quality in Jiangsu Province

[Objective] The aim of this study was to explore the dominant fiber quality traits of test sites in cotton regional trials, by analyzing the regional characteristics of cotton fiber quality in Jiangsu province, in order to provide the theory background for cotton fiber quality improvement. [Method] The dominant fiber quality traits of test locations were analyzed with eight main fiber quality indexes of hybrid cotton regional trials during 2009-2013 in Jiangsu province by use of the "ideal test site" view of GGE biplot. [Result] The test locations with the best integrative fiber quality were proved to be Yanliang, and followed by Dongxin and Guanyun; The better test locations in terms of the major fiber quality indexes, including fiber strength, fiber Length and micronaire value, were Guanyun, Xinyang and Yanliang; To sum up, the best test location with balanced fiber quality was Yanliang. The test locations with specialties in fiber quality index were listed as bellow: Dafeng, Xinghua and Dongtai performance better in fiber length; Qidong, Liuhe and Yanhai locations were of better fiber length uniformity; Sheyang and Dongxin were better in micronaire value;while Sheyang along was better in fiber elongation and reflectance. Moreover, the correlation between fiber yellowness and other traits was significant(P<0.01). [Conclusion] The regional characteristic of cotton fiber quality index in Jiangsu province was obvious and fiber yellowness was worthy an indicator trait to assist the comprehensive improvement of cotton fiber quality.

Plate Shape Control Theory and Experiment for 20-high Mill

Roll flattening theory is an important part of plate shape control theories for 20-high mill. In order to improve the accuracy of roll flattening calculation for 20-high mill, a new and more accurate roll flattening model was proposed. In this model, the roll barrel was considered as a finite length semi-infinite body. Based on the boundary integral equation method, the numerical solution of the finite length semi-infinite body under the distributed force was obtained and an accurate roll flattening model was established. Coupled with roll bending model and strip plastic deformation, a new and more accurate plate control model for 20-high mill was established. Moreover, the effects of the first intermediate roll taper angle and taper length were analyzed. The tension distribution calculated by analytical model was consistent with the experimental results.