基于疏水聚集作用的pH、电流以及热响应性的多形状记忆水凝胶研究

多重敏感和多重形状记忆功能是形状记忆材料发展的两大趋势。本文研究了一种对pH、电流及热敏感,并具备性多重形状记忆功能的聚丙烯酰胺基水凝胶。其中。水凝胶中修饰的丹磺酰基团由于可在水溶液中表现出pH值以及热敏感性的疏水聚集,因此可以作为水凝胶形状记忆性能的可逆的分子开关。研究结果表明:在低pH值或较高温度下,由于丹磺酰基团形成疏水聚集开关被打开,材料表现出优异的pH、温度以及电流响应的形状记忆功能,其双重形状记忆的形状固定率和回复率均可达100%。并且,由于该水凝胶具有很宽的玻璃化转变温度范围,因此在0-90℃范围还可表现出热诱导的三形状记忆性能。这些多功能的形状记忆性能使材料更能满足复杂的应用要..

Measurement of integrated luminosity of data collected at 3.773 GeV by BESIII from 2021 to 2024

We present a measurement of the integrated luminosity e+e- of collision data collected by the BESIII detector at the BEPCII collider at a center-of-mass energy of Ecm = 3.773 GeV. The integrated luminosities of the datasets taken from December 2021 to June 2022, from November 2022 to June 2023, and from October 2023 to February 2024 were determined to be 4.995±0.019 fb-1, 8.157±0.031 fb-1, and 4.191±0.016 fb-1, respectively, by analyzing large angle Bhabha scattering events. The uncertainties are dominated by systematic effects, and the statistical uncertainties are negligible. Our results provide essential input for future analyses and precision measurements

Determination of the number of ψ(3686) events taken at BESIII

The number of ψ(3686) events collected by the BESIII detector during the 2021 run period is determined to be (2259.3±11.1)×106 by counting inclusive ψ(3686) hadronic events. The uncertainty is systematic and the statistical uncertainty is negligible. Meanwhile, the numbers of ψ(3686) events collected during the 2009 and 2012 run periods are updated to be (107.7±0.6)×106 and (345.4±2.6)×106, respectively. Both numbers are consistent with the previous measurements within one standard deviation. The total number of ψ(3686) events in the three data samples is (2712.4±14.3)×10^