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Early selection efficiency for fiber dimensions and their relationships with growth and wood quality for Pinus elliotth Engelm.in southern China
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作者 Jing Wen Min Yi +5 位作者 Leiming Dong Lu Zhang Siyu Liu Shenggui Yuan xiaoxiao tao Meng Lai 《Journal of Forestry Research》 SCIE CAS CSCD 2023年第6期1951-1962,共12页
A solid understanding of the efficiency of early selection for fiber dimensions is a prerequisite for breeding slash pine(Pinus elliottii Engelm.)with improved properties for pulp and paper products.Genetic correlatio... A solid understanding of the efficiency of early selection for fiber dimensions is a prerequisite for breeding slash pine(Pinus elliottii Engelm.)with improved properties for pulp and paper products.Genetic correlations between size of fibers,wood quality and growth properties are also important.To accomplish effective early selection for size of fibers and evaluate the impact for wood quality traits and ring widths,core samples were collected from360 trees of 20 open-pollinated Pinus elliottii families from three genetic trials.Cores were measured by SilviScan,and the age trends for phenotypic values,heritability,early-late genetic correlations,and early selection efficiency for fiber dimensions,such as tangential and radial fiber widths,fiber wall thickness and fiber coarseness,and their correlations with microfibril angle(MFA),modulus of elasticity(MOE),wood density and ring width were investigated.Different phenotypic trends were found for tangential and radial fiber widths while fiber coarseness and wall thickness curves were similar.Age trends of heritability based on area-weighted fiber dimensions were different.Low to moderate heritability from pith to bark(~0.5)was found for all fiber dimension across the three sites except for tangential fiber width and wall thickness at the Ganzhou site.Early-late genetic correlations were 0.9 after age of 9 years,and early selection for fiber dimensions could be effective due to strong genetic correlations.Our results showed moderate to strong positive genetic correlations for modulus of elasticity and density with fiber dimensions.The effects on fiber dimensions were weak or moderate when ring width or wood quality traits were selected alone.Estimates of efficiency for early selection indicated that the optimal age for radial fiber width and fiber coarseness was 6-7 years,while for tangential fiber width and wall thickness was 9-10 years. 展开更多
关键词 Pinus elliottii Early selection efficiency Genetic correlation HERITABILITY Fiber dimensions
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高官能度聚氨酯丙烯酸酯的设计制备及光固化性能 被引量:6
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作者 董文静 段华军 +1 位作者 陶晓晓 汪鑫 《高分子材料科学与工程》 EI CAS CSCD 北大核心 2018年第10期129-134,共6页
为了提高树脂的光固化活性,以不同官能度的苯酐聚酯多元醇(PAPP)为核,异佛尔酮二异氰酸酯(IPDI)和季戊四醇三丙烯酸酯(PET3A)为支设计制备了一系列高官能度聚氨酯丙烯酸酯。将其与活性稀释剂、光引发剂复配,通过紫外光(UV)固化,得到树... 为了提高树脂的光固化活性,以不同官能度的苯酐聚酯多元醇(PAPP)为核,异佛尔酮二异氰酸酯(IPDI)和季戊四醇三丙烯酸酯(PET3A)为支设计制备了一系列高官能度聚氨酯丙烯酸酯。将其与活性稀释剂、光引发剂复配,通过紫外光(UV)固化,得到树脂浇铸体。用红外光谱、UV固化机、万能材料试验机、动态力学热分析仪及同步热分析等对光固化树脂及其浇铸体的结构、活性、力学及热学性能等进行测试分析。结果表明,合成了预期结构的聚氨酯丙烯酸酯,当其碳碳双键官能度从6增加到12时,树脂湿膜(100μm)光固化时间从21 s下降至18 s;树脂浇铸体弯曲与拉伸性能呈上升趋势,冲击韧性则有所降低; Tg从135℃上升到147℃,耐热性能变好。 展开更多
关键词 紫外光固化 聚氨酯丙烯酸酯 高官能度 光固化活性
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