基于聚(L-谷氨酸)树状分子的智能药物释放系统研究

以天然氨基酸L-谷氨酸为原料,通过收敛法合成了聚(L-谷氨酸)树状分子,通过半胱氨酸将抗肿瘤药物甲氨蝶呤( MTX)键合到聚(L-谷氨酸)树状分子上,构建氧化还原敏感的药物传输系统.用核磁(1H～NMR)等对载体以及载药粒子进行了表征.体外释放研究发现,载药粒子具有良好的氧化还原响应性,在不同浓度的还原剂二硫苏糖醇(D...     

七(2,3,6-三-O-甲氧甲基)-β-环糊精的合成及其在气相色谱分离中的应用

将甲氧甲基引入β-环糊精的2,3,6-位合成了新的气相色谱手性固定相七(2,3,6-三-O-甲氧甲基)-β-环糊精,并采用静态法将其涂渍在毛细管内壁制备毛细管气相色谱柱。考察了毛细管柱的柱性能和分离性能。结果表明该固定相对Grob试剂、苯的二取代位置异构体(硝基甲苯、溴甲苯、二氯苯和二甲苯)及手性化合物(2-羟基丙酸甲酯、2-羟基丙酸乙酯和2-甲磺酰基丙酸甲酯)都具有良好的分离效果。与固定相2,3,6-三-O-甲基-β-环糊精的手性分离效果对比,结果显示两种手性固定相的分离能力各异,对一些手性脂类化合物对映体的分离存在互补性。     

拉盖尔-高斯幂指数相位涡旋光束传输特性

为实现光折射率传感器小结构、高灵敏度的要求,根据表面等离极化激元的透射特性,提出了一种单挡板金属-介质-金属（MIM）波导耦合类云朵腔结构。此结构引用“腔中腔”的理念,在近场耦合作用下,类云朵腔所形成的较宽的连续态与金属挡板所形成的较窄的离散态经过干涉相长相消,可以产生三重不同模式的法诺共振。结合耦合模理论,对三重法诺共振的产生机理进行分析,并运用有限元分析法对此结构进行模拟仿真,定量分析了不同结构参数对折射率传感特性以及优质因子的影响。结果表明,三种共振模式的灵敏度分别为600,800,1083 nm/RIU,优质因子分别为5.08×10⁴、3.56×10⁵和1.17×10³。     

Detumbling strategy and coordination control of kinematically redundant space robot after capturing a tumbling target

This paper focuses on the motion planning to detumble and control of a space robot to capture a non-cooperative target satellite. The objective is to construct a detumbling strategy for the target and a coordination control scheme for the space robotic system in post-capture phase. First, the dynamics of the kinematically redundant space robot after grasping the target is presented, which lays the foundation for the coordination controller design. Subsequently, optimal detumbling strategy for the post-capture phase is proposed based on the quartic B\(\acute{\text{ e }}\)zier curves and adaptive particle swarm optimization algorithm subject to the specific constraints. Both detumbling time and control torques were taken into account for the generation of the optimal detumbling strategy. Furthermore, a coordination control scheme is designed to track the designed reference path while regulating the attitude of the chaser to a desired value. The space robot successfully dumps the initial velocity of the tumbling satellite and controls the base attitude synchronously. Simulation results are presented for detumbling a target with rotational motion using a seven degree-of-freedom redundant space manipulator, which demonstrates the feasibility and effectiveness of the proposed method.     

高氮奥氏体不锈钢高温动态响应特性及本构关系

在293~873 K的环境下,采用分离式霍普金森杆装置对高氮钢试样进行了102~103 s-1应变率下的动态加载实验。结合准静态实验结果,分析了应变率和温度对材料塑性流动特性的影响。结果表明:高氮钢的动态力学行为具有很强的应变率敏感性和温度敏感性。当应变率达到400 s-1或更高时,流动应力随应变率的增加显著升高;在同一应变率下,流动应力随温度的降低明显升高。研究了温度和应变率耦合效应对材料塑性行为的影响,得出温度软化效应在高氮钢高温动态塑性变形中起主导作用。基于经典的Johnson-Cook（J-C）模型,通过对实验数据的分析,得出了高氮钢材料的修正J-C本构方程,经验证修正J-C方程预测结果与实验结果吻合。     

Electrically tunable magnetic configuration on vacancy-doped GaSe monolayer

Group-IIIA metal-monochalcogenides with the enticing properties have attracted tremendous attention across various scientific disciplines. With the aim to satisfy the multiple demands of device applications, here we report a design framework on GaSe monolayer in an effort to tune the electronic and magnetic properties through a dual modulation of vacancy doping and electric field. A half-metallicity with a 100% spin polarization is generated in a Ga vacancy doped GaSe monolayer due to the nonbonding 4p electronic orbital of the surrounding Se atoms. The stability of magnetic moment is found to be determined by the direction of applied electric field. A switchable magnetic configuration in Ga vacancy doped GaSe monolayer is achieved under a critical electric field of 0.6 V/Å. Electric field induces redistribution of the electronic states. Finally, charge transfers are found to be responsible for the controllable magnetic structure in this system. The magnetic modulation on GaSe monolayer in this work offers some references for the design and fabrication of tunable two-dimensional spintronic device.     

离子色谱法测定卷烟主流烟气中氨含量的不确定度评定

根据《测量不确定度评定与表示》对离子色谱法测定卷烟主流烟气中氨含量的不确定度进行评定,通过分析得出,测量重复性、线性回归方程以及标准溶液的配制是不确定度的主要来源。分析结果结果表明,当卷烟样品主流烟气中氨释放量为12.04μg/支时,扩展不确定度为0.40μg/支,k=2。     

CFETR TF Dummy 线圈 VPI 系统设计

TF 线圈为大型“D”形轮廓, 由高、 中、 低场线圈通过套装和堆叠而成. 需要分别对高中低场线圈进行绝缘处理, 套装后填充高中低场之间的间隙(10 mm~120 mm) , 包绕对地绝缘后, 再对间隙填充层进行绝缘处理. 为了充分验证绕组制造的工艺, 采用一个以中场绕组尺寸的Dummy 绕组进行真空压力浸渍(Vacuum Pressure Impregnation, VPI) 完成线圈绝缘. 针对 VPI 过程中真空环境、 外部压力、 固化温度、 时间控制等方面的技术难点, 完成 TF Dummy 线圈 VPI 系统设计. 采用 CATIA 软件对 Dummy 线圈 VPI 系统进行建模, 合理设计子系统, 有效缩短 VPI过程的时间, 保证绝缘质量. 通过每个子系统的理论分析计算, 更精确地选择 VPI 系统配备的设备型号,CFETR TF Dummy 线圈 VPI 系统的设计和相关工艺的验证对后续 TF 线圈制造至关重要.     

Balancing Interfacial Reactions through Regulating p-Band Centers by an Indium Tin Oxide Protective Layer for Stable Zn Metal Anodes

Metallic zinc (Zn) is considered as one of the most attractive anode materials for the post-lithium metal battery systems owing to the high theoretical capacity, low cost, and intrinsic safety. However, the Zn dendrites and parasitic side reaction impede its application. Herein, we propose a new principle of regulating p-band center of metal oxide protective coating to balance Zn adsorption energy and migration energy barrier for effective Zn deposition and stripping. Experimental results and theoretical calculations indicate that benefiting from the uniform zincophilic nucleation sites and fast Zn transport on indium tin oxide (ITO), highly stable and reversible Zn anode can be achieved. As a result, the I−Zn symmetrical cell achieves highly reversible Zn deposition/stripping with an extremely low overpotential of 9 mV and a superior lifespan over 4000 h. The Cu/I−Zn asymmetrical cell exhibits a long lifetime of over 4000 cycles with high average coulombic efficiency of 99.9 %. Furthermore, the assembled I−Zn/AC full cell exhibits an excellent lifetime for 70000 cycles with nearly 100 % capacity retention. This work provides a general strategy and new insight for the construction of efficient Zn anode protection layer.