摘要：We study the expansion behaviors of a Fermionic superfluid in a cigar-shaped optical dipole trap for the whole BEC-BCS crossover and various *** low temperature(0:06(1)T_F),the atom cloud undergoes an anisotropic hydrodynamic expansion over 30 ms,which behaves like oscillation in the horizontal *** analyzing the expansion dynamics according to the superfluid hydrodynamic equation,the effective polytropic index y of Equation-of-State(EoS)of Fermionic superfluid is *** y values show a non-monotonic behavior over the BEC-BCS crossover,and have a good agreement with the theoretical results in the unitarity and BEC *** normalized quasi-frequencies of the oscillatory expansion are measured,which drop significantly from the BEC side to the BCS side and reach a minimum value of 1.73 around 1/k_Fa=-0:*** work improves the understanding of the dynamic properties of strongly interacting Fermi gas.

摘要：受天然酶启发,协同作用被广泛应用于小分子的识别及其催化转化,但在聚合物合成领域的研究仍然有限.本文报道了一种柔性桥联双核卟啉铝催化剂(FTBC),成功实现了CO_(2)与环氧丙烷(PO)的高效交替共聚.该策略的关键在于通过调控柔性链的长度使得活性位点相互靠近,从而促进分子内协同作用.受益于活性位点的协同效应,以―CH_(2)―为柔性链的C_(1)-Al_(2)表现出优异的催化活性(380 h^(−1))及较高的聚合物选择性(96%),优于相同条件下的单分子卟啉铝(活性为300 h^(−1),聚合物选择性为78%).即使在低催化剂浓度下,C_(1)-Al_(2)也能保持较好催化活性(250 h^(−1)).动力学实验表明C_(1)-Al_(2)反应级数为一级,证实催化剂的分子内协同催化主导共聚过程.本文报道了一种柔性桥联双核催化剂的构筑策略,为模块化设计高性能催化剂提供了新方向.

摘要：为进一步培养化学专业本科生的实践能力和创新性思维,本研究设计绿色电化学合成技术制备含氟化合物开放实验,创新绿色合成含氟化合物的方法,增设查询文献的环节,筛选最优反应条件,最终通过更加环保的方法合成含氟化合物。该开放实验合理利用实验室资源,提升学生的实验创新探究能力和独立分析解决问题的能力,将科技前沿知识融入本科实验教学,为学生今后独立开展绿色有机合成科学研究打下基础。该类开放性实验创新了实验教学方法,完善了教学体系,对提升高校有机化学实验教学效果具有显著效果。

摘要：For generating a uniform and steady magnetic field, Helmholtz coil is extensively used in nuclear magnetic resonance gyro(NMRG). Unfortunately, the volume of Helmholtz coil makes it inconvenient to miniaturize NMRG. This study introduces Braunbeck coil that can be used in magnetic field excitation system. Braunbeck coil can produce homogeneous magnetic field within a limit space, and occupy a small volume. In addition, this study presents mathematical expressions that can be used to calculate the area of uniform magnetic field. Experimental test verifies the effectiveness of the proposed design, and the results accord closely with the actual simulation.

摘要：研究通讯拓扑为符号有向图的人在环多机械臂系统的预设性能二分一致性跟踪控制问题.为在预设时间内收敛到预设精度,提出一种基于观测器的预设性能控制策略.首先,设计预设时间和精度的观测器以估计领导者的输出信息,通过合作/竞争信息交互实现观测器输出的二分一致性.该观测器不需要领导机械臂的输入信息及输出信息的高阶导数,并通过无芝诺行为的事件触发机制降低不同机械臂间的通讯负担.其次,通过反步法及误差转化法将有约束的机械臂输出跟踪问题转化为无约束的误差系统稳定性问题,进而基于观测器输出设计机械臂的输出调节控制器.值得一提的是,设计的控制策略不需要系统初始状态的先验知识且避免了预设时刻控制增益无穷大的现象,增强了系统的可靠性.最后,仿真结果表明所提控制策略的可行性及优越性.

摘要：为了适应以RBCC为动力的飞行器的总体发展需求,对RBCC推进系统总体设计要求评估方法进行了研究。分别提出了RBCC飞行器总体设计和推进系统总体设计结构矩阵,并分析了其应用范围以及对RBCC推进系统总体设计的指导作用。建立了发动机推力性能设计要求、推进剂质量需求和推进剂冷却性能需求的理论分析方法,实现了RBCC推进系统总体设计要求评估模型,并对空中载机发射的RBCC巡航飞行器进行了推进系统总体设计要求分析。

摘要：研究了一种用于火箭基组合循环发动机(RBCC)初步设计与方案分析的CAD系统。分析并解决了发动机几何特征参数提取、性能分析模型、设计计算集成、三维图形造型与显示等关键技术。基于AC IS几何造型内核软件,搭建了火箭基组合循环发动机初步设计的CAD平台,并利用该平台进行了算例分析。结果表明,该CAD平台能有效地进行火箭基组合循环发动机的设计与分析,实现了设计、计算一体化,为此类发动机实验器的设计提供了技术支持。

摘要：Excited-state double proton transfer(ESDPT)is a controversial issue which has long been plagued with theoretical and experimental ***,we took 1,8-dihydroxy-2-naphthaldehyde(DHNA)as a prototype and used combined complete active space selfconsistent field(CASSCF)and multi-state complete active-space second-order perturbation(MS-CASPT2)methods to investigate ESDPT and excited-state deactivation pathways of *** different tautomer minima of S1-ENOL,S1-KETO-1,and S1-KETO-2 and two crucial conical intersections of S1 S0-KETO-1 and S1 S0-KETO-2 in and between the S0 and S1 states were obtained.S1-KETO-1 and S1-KETO-2 should take responsibility for experimentally observing dual-emission *** addition,two-dimensional potential energy surfaces(2 D-PESs)and linear interpolated internal coordinate paths connecting relevant structures were calculated at the MS-CASPT2//CASSCF level and confirmed a stepwise ESDPT ***,the first proton transfer from S1-ENOL to S1-KETO-1 is barrierless,whereas the second one from S1-KETO-1 to S1-KETO-2 demands a barrier of ca.6.0 kcal/*** linear interpolated internal coordinate path connecting S1-KETO-1(S1-KETO-2)and S_(1) S0-KETO-1(S1 S0-KETO-2)is uphill with a barrier of ca.12.0 kcal/mol,which will trap DHNA in the S_(1) state while therefore enabling dual-emission *** the other hand,the S1/S0 conical intersections would also prompt the S_(1) system to decay to the S_(0) state,which could be to certain extent suppressed by locking the rotation of the C5-C8-C9-O10 dihedral *** mechanistic insights are not only helpful for understanding ESDPT but also useful for designing novel molecular materials with excellent photoluminescent performances.

摘要：Real-time monitoring of the Bragg peak location of carbon ions is urgently required for the quality control of hadron therapy. In this study, we design an annular detector to monitor the Bragg peak location of carbon ions with Geant4 simulation. This 360° surrounding structure has a high detection efficiency for the small-dose situation. The detector consists of a multilayered collimator system and an Na I scintillator for prompt gamma counting. The multilayered collimator includes a lead layer to prevent unwanted gammas and the paraffin and boron carbide layers to moderate and capture fast neutrons. An inclination of the detector further diminishes the background signal caused by neutrons. The detector, with optimized parameters, is applicable to carbon ions of different energies. In addition, the scintillator is replaced by an improved EJ301 organic liquid scintillator to discriminate gammas and neutrons. Inserting thin Fe slices into the liquid scintillator improves the energy deposition efficiency. The Bragg peak location of 200 Me V/u carbon ions can be monitored by prompt gamma detection with the improved liquid scintillator.

摘要：对火箭基组合循环(RBCC)发动机火箭引射模态下一次火箭流量优化方法开展了研究,并对飞行条件下一次火箭流量的变化规律进行了分析。提出了采用有效比冲作为优化目标的一次火箭流量单目标优化模型;建立了求解与一次火箭流量相匹配的二次燃料流量的比例控制方法;在考虑发动机性能优化与弹道分析耦合作用的基础上,采用试验设计和遗传算法,建立了火箭引射模态下一次火箭流量优化方法。针对空中载机发射的RBCC发动机,开展了火箭引射模态下一次火箭流量优化,并根据弹道分析结果,给出了飞行条件下一次火箭流量变化规律。结果表明,为了克服飞行过程中声障阻力,一次火箭流量在Ma=1.0附近达到最大,此时对发动机提出较高的推力设计要求;在Ma=1.5附近,来流空气的冲压作用占主导地位,一次火箭流量出现较大程度的节流,此时对发动机提出较高的比冲设计要求;超过Ma=1.5后,一次火箭以较小的流量状态维持稳定工作;火箭引射模态下一次火箭流量调节比达到了5.0。