The genetic base that cotton breeders commonly use to improve Upland cultivars is very narrow.The AD-genome species Gossypium barbadense,G.tomentosum,and G.mustelinum are part of
A quasi-isentropic study on the process of driving a cylinder with aluminized explosives was carried out to examine the influence of the aluminum(Al) reaction rate on cylinder expansion and the physical parameters of ...A quasi-isentropic study on the process of driving a cylinder with aluminized explosives was carried out to examine the influence of the aluminum(Al) reaction rate on cylinder expansion and the physical parameters of the detonation products. Based on the proposed quasi-isentropic hypothesis and relevant isentropic theories, the characteristic lines of aluminized explosives driving a cylinder were analyzed,and a quasi-isentropic model was established. This model includes the variation of the cylinder wall velocity and the physical parameters of the detonation products with the Al reaction degree. Using previously reported experimental results, the quasi-isentropic model was verified to be applicative and accurate. This model was used to calculate the physical parameters for cylinder experiments with aluminized cyclotrimethylenetrinitramine explosives with 15.0 % and 30.0 % Al content. The results show that this quasi-isentropic model can be used not only to calculate the cylinder expansion rule or Al reaction degree, but also to calculate the physical parameters of the detonation products in the process of cylinder expansion. For explosives with 15.0 % and 30.0 % Al, 24.3 % and 18.5 % of the Al was found to have reacted at 33.9 μs and 34.0 μs, respectively. The difference in Al content results in different reaction intensity, occurrence time, and duration of two forms of reaction(diffusion and kinetic) between the Al powder and the detonation products;the post-detonation burning reaction between the Al powder and the detonation products prolongs the positive pressure action time, resulting in a continuous rise in temperature after detonation.展开更多
The near crack line analysis method was used to investigate a crack loaded by two pairs of point shear forces in an infinite plate in an elastic-perfectly plastic solid, and the analytical solution was obtained. The s...The near crack line analysis method was used to investigate a crack loaded by two pairs of point shear forces in an infinite plate in an elastic-perfectly plastic solid, and the analytical solution was obtained. The solutions include: the unit normal vector of the elastic-plastic boundary near the crack line, the elastic-plastic stress fields near crack line, law that the length of the plastic zone along the crack line is varied with an external loads, and the bearing capacity of an infinite plate with a center crack loaded by two pairs of point shear forces. The results are sufficiently precise near the crack line because the assumptions of the small scale yielding theory have not been made and no other assumption have been taken.展开更多
Genetic linkage relationship of the natural colored fiber and six fuzzless seed germplasms in obsolete backgrounds of Gossypium hirsutum(AD genome) and G.barbadense were analyzed in the
辣椒作为常异花授粉作物,在生产实际中利用核不育两用系进行制种是理想手段。α-微管蛋白(α-tubulin)是细胞骨架的主要成分,与植物育性相关。以辣椒核不育两用系AB114为材料,采用扩增片段长度多态性(amplified fragment length polymor...辣椒作为常异花授粉作物,在生产实际中利用核不育两用系进行制种是理想手段。α-微管蛋白(α-tubulin)是细胞骨架的主要成分,与植物育性相关。以辣椒核不育两用系AB114为材料,采用扩增片段长度多态性(amplified fragment length polymorphism,AFLP)技术得到蕾期基因表达差异片段,利用cDNA末端快速扩增(rapid-amplifi cation of cDNA ends,RACE)技术克隆AFLP-F-57全长。ORF finder分析显示,该基因具有1350 bp的最大开放阅读框,编码450个氨基酸;经Standard Protein BLAST和NCBI Conserved Domain Search鉴定,该基因编码蛋白与烟草、辣椒的α-微管蛋白具有高度相似性,均含有α-tubulin保守结构域,故将其命名为CaTUA基因;RT-PCR分析表明,与可育株相比,不育株中该基因的表达量随花蕾发育呈现下降趋势,于大花蕾时期差异显著;系统进化树分析发现CaTUA蛋白与烟草TUA蛋白序列的进化距离较近。研究初步分析了CaTUA基因的功能,为进一步揭示辣椒核不育与CaTUA的关系提供了理论依据。展开更多
文摘The genetic base that cotton breeders commonly use to improve Upland cultivars is very narrow.The AD-genome species Gossypium barbadense,G.tomentosum,and G.mustelinum are part of
基金National Natural Science Foundation of China(Grant No.11872120).
文摘A quasi-isentropic study on the process of driving a cylinder with aluminized explosives was carried out to examine the influence of the aluminum(Al) reaction rate on cylinder expansion and the physical parameters of the detonation products. Based on the proposed quasi-isentropic hypothesis and relevant isentropic theories, the characteristic lines of aluminized explosives driving a cylinder were analyzed,and a quasi-isentropic model was established. This model includes the variation of the cylinder wall velocity and the physical parameters of the detonation products with the Al reaction degree. Using previously reported experimental results, the quasi-isentropic model was verified to be applicative and accurate. This model was used to calculate the physical parameters for cylinder experiments with aluminized cyclotrimethylenetrinitramine explosives with 15.0 % and 30.0 % Al content. The results show that this quasi-isentropic model can be used not only to calculate the cylinder expansion rule or Al reaction degree, but also to calculate the physical parameters of the detonation products in the process of cylinder expansion. For explosives with 15.0 % and 30.0 % Al, 24.3 % and 18.5 % of the Al was found to have reacted at 33.9 μs and 34.0 μs, respectively. The difference in Al content results in different reaction intensity, occurrence time, and duration of two forms of reaction(diffusion and kinetic) between the Al powder and the detonation products;the post-detonation burning reaction between the Al powder and the detonation products prolongs the positive pressure action time, resulting in a continuous rise in temperature after detonation.
文摘The near crack line analysis method was used to investigate a crack loaded by two pairs of point shear forces in an infinite plate in an elastic-perfectly plastic solid, and the analytical solution was obtained. The solutions include: the unit normal vector of the elastic-plastic boundary near the crack line, the elastic-plastic stress fields near crack line, law that the length of the plastic zone along the crack line is varied with an external loads, and the bearing capacity of an infinite plate with a center crack loaded by two pairs of point shear forces. The results are sufficiently precise near the crack line because the assumptions of the small scale yielding theory have not been made and no other assumption have been taken.
文摘Genetic linkage relationship of the natural colored fiber and six fuzzless seed germplasms in obsolete backgrounds of Gossypium hirsutum(AD genome) and G.barbadense were analyzed in the
文摘辣椒作为常异花授粉作物,在生产实际中利用核不育两用系进行制种是理想手段。α-微管蛋白(α-tubulin)是细胞骨架的主要成分,与植物育性相关。以辣椒核不育两用系AB114为材料,采用扩增片段长度多态性(amplified fragment length polymorphism,AFLP)技术得到蕾期基因表达差异片段,利用cDNA末端快速扩增(rapid-amplifi cation of cDNA ends,RACE)技术克隆AFLP-F-57全长。ORF finder分析显示,该基因具有1350 bp的最大开放阅读框,编码450个氨基酸;经Standard Protein BLAST和NCBI Conserved Domain Search鉴定,该基因编码蛋白与烟草、辣椒的α-微管蛋白具有高度相似性,均含有α-tubulin保守结构域,故将其命名为CaTUA基因;RT-PCR分析表明,与可育株相比,不育株中该基因的表达量随花蕾发育呈现下降趋势,于大花蕾时期差异显著;系统进化树分析发现CaTUA蛋白与烟草TUA蛋白序列的进化距离较近。研究初步分析了CaTUA基因的功能,为进一步揭示辣椒核不育与CaTUA的关系提供了理论依据。
