为了探究棉花的耐盐机制,以中棉所49、中棉所35和中51504为材料,研究了盐胁迫对棉花幼苗的生长及K+/Na+平衡生理的影响。结果表明,150 mmol·L-1 Na Cl处理对幼苗的生长具有明显抑制作用,降低了叶片的光合速率(Pn)、PSⅡ实际光量子...为了探究棉花的耐盐机制,以中棉所49、中棉所35和中51504为材料,研究了盐胁迫对棉花幼苗的生长及K+/Na+平衡生理的影响。结果表明,150 mmol·L-1 Na Cl处理对幼苗的生长具有明显抑制作用,降低了叶片的光合速率(Pn)、PSⅡ实际光量子产额(ΦPSII)和电子传递速率(ETR),增加了非光化学荧光猝灭系数(q N)。与中棉所49和中棉所35相比,中51504的干物质累积受盐胁迫影响最小,且保持较高的Pn、ΦPSII、ETR和q N值及较低的ETR/Pn值。盐胁迫提高了棉花组织中Na+的浓度,降低了K+的浓度;但中51504组织中保持了相对较低的Na+浓度和较高的K+浓度,维持了较高的K+/Na+比;通过非损伤微测技术(NMT)测定的离子流结果也表明,中51504的根系对Na+有较强的外排能力,而对K+有较强的保留和向地上部转运能力。能够有效地调节Na+和K+的跨膜转运进而维持K+/Na+平衡是棉花耐盐的重要生理机制之一。展开更多
Cross sections for K-shell ionization have been measured at electron energies of 0.1-0.40 MeV for Cu and Sn, and of 0.30MeV for Ag. The present results have been compared with theoretical calculations and previously r...Cross sections for K-shell ionization have been measured at electron energies of 0.1-0.40 MeV for Cu and Sn, and of 0.30MeV for Ag. The present results have been compared with theoretical calculations and previously reported experimental values.展开更多
The influence of the chiral mean field on the in-plane flow in heavy ion collisions at SIS energy is investigated within covariant kaon dynamics. For the kaon mesons inside the nuclear medium a quasi-particle picture...The influence of the chiral mean field on the in-plane flow in heavy ion collisions at SIS energy is investigated within covariant kaon dynamics. For the kaon mesons inside the nuclear medium a quasi-particle picture including scalar and vector fields is adopted and compared to the standard treatment with a static potential. It is confirmed that a Lorentz force from spatial component of the vector field provides an important contribution to the in-medium kaon dynamics and strongly counterbalances the influence of the vector potential on the in-plane flow. The calculated results show that the new FOPI data can be reasonably described using the Brown & Rho parametrization, which partly takes into account the correction of higher order contributions in the chiral expansion. This indicates that one can abstract the information on the kaon potential in a nuclear medium from the analysis of the in-plane flow.展开更多
The energy spectra of reflected electrons from the substrates of targets have been calculated by the bipartition model of electron transport, the contributions of the inner shen ionization events produced by the refle...The energy spectra of reflected electrons from the substrates of targets have been calculated by the bipartition model of electron transport, the contributions of the inner shen ionization events produced by the reflected electrons from the substrates in the targets to the x-ray counting in a St(Li) detector have been estimated. It has been confirmed that, by such correction to the measured data, the experimental results of inner shell ionization cross sections by electron impact with fine precision may be obtained under the condition of thick substrate.展开更多
文摘Cross sections for K-shell ionization have been measured at electron energies of 0.1-0.40 MeV for Cu and Sn, and of 0.30MeV for Ag. The present results have been compared with theoretical calculations and previously reported experimental values.
文摘The influence of the chiral mean field on the in-plane flow in heavy ion collisions at SIS energy is investigated within covariant kaon dynamics. For the kaon mesons inside the nuclear medium a quasi-particle picture including scalar and vector fields is adopted and compared to the standard treatment with a static potential. It is confirmed that a Lorentz force from spatial component of the vector field provides an important contribution to the in-medium kaon dynamics and strongly counterbalances the influence of the vector potential on the in-plane flow. The calculated results show that the new FOPI data can be reasonably described using the Brown & Rho parametrization, which partly takes into account the correction of higher order contributions in the chiral expansion. This indicates that one can abstract the information on the kaon potential in a nuclear medium from the analysis of the in-plane flow.
文摘The energy spectra of reflected electrons from the substrates of targets have been calculated by the bipartition model of electron transport, the contributions of the inner shen ionization events produced by the reflected electrons from the substrates in the targets to the x-ray counting in a St(Li) detector have been estimated. It has been confirmed that, by such correction to the measured data, the experimental results of inner shell ionization cross sections by electron impact with fine precision may be obtained under the condition of thick substrate.
