爆炸作用驱动液体抛撒初始阶段数值仿真

 针对灭火战斗部引战配合设计,研究爆炸作用驱动液体（水基灭火剂）抛撒初始阶段的特性。依据典型灭火战斗部的结构建立数值仿真模型,采用LS-DYNA软件进行仿真计算,分别获得了加载系数（驱动装药与液体的质量比）对壳体破裂时间和壳体破裂初期液体/空气界面运动速度的影响规律,以及液体/空气界面后续的运动特性。进行了同条件下爆炸驱动水基灭火剂抛撒实验,得到了不同加载系数条件下壳体破裂初期液体/空气界面的运动速度。实验结果与数值仿真结果吻合良好,表明所采用的数值仿真方法具有正确性和有效性,对相关问题的研究具有重要参考价值。     

Observation of E×B Flow Velocity Profile Change Using Doppler Reflectometry in HL-2A

A broadband, O-mode sweeping Doppler reflectometry designed for measuring plasma E×B flow velocity profiles is operated in HL-2A. The main feature of the Doppler reflectometry is its capability to be tuned to any selected frequency in total waveband from 26-40 GHz. This property enables us to probe several plasma layers within a short time interval during a discharge, permitting the characterization of the radial distribution of plasma fluctuations. The system allows us to extract important information about the velocity change layer, namely its spatial localization. In purely Ohmic discharge a change of the E×B flow velocity profiles has been observed in the region for 28 〈 r 〈 30cm if only the line average density exceeds 2.2×10^19 m^-3. The density gradient change is measured in the same region, too.     

Interfacial effect on the reverse of magnetization and ultrafast demagnetization in Co/Ni bilayers with perpendicular magnetic anisotropy

For static magnetic properties of the Co/Ni bilayers, macroscopic hysteresis loops and microscopic magnetic moment distributions have been determined by the object oriented micromagnetic framework(OOMMF). It is found that when the bilayer systems are fully decoupled, the magnetizations of the two phases reverse separately. The coercivity of the bilayers decreases to a valley value sharply with increasing interfacial exchange coupling and then rises slowly to a platform. On the other hand, we have carried out an atomistic simulation for the laser-induced ultrafast demagnetization of the Co/Ni bilayer. A larger damping constant leads to a faster demagnetization as well as a larger degree of demagnetization, which is consistent with the first-principle theoretical results. For the magnetization recovery process, the damping constant has different influences on the recovery time with various peak electron temperatures, which is ignored in previous atomistic simulations as well as the Landau–Liftshit–Bloch(LLB) micromagnetic calculations. Furthermore, as the interfacial exchange coupling increases, the ultrafast demagnetization curves for Co and Ni become coincident, which is a demonstration for the transition from two-phase phenomenon to single-phase phenomenon.     

纳米纤维状Sr3Al2O5Cl2:Eu2+,Tm3+的白色长余辉性能

采用高温固相法在800℃下制备出系列白色长余辉荧光粉Sr₃Al₂O₅Cl₂：Eu²⁺,Tm³⁺,并研究了它们的结构、形貌及发光性能。样品Sr_2.91Al₂O₅Cl₂：0.04Eu²⁺,0.05 Tm³⁺具有单一晶相和纳米纤维结构。该样品在紫外光激发下表现出两个很强的宽带发射（分别位于~448 nm和~590 nm）。它的余辉寿命大约是20 min。利用此种荧光粉所制作出的白光LED器件表现出很强的白光发射。     

HT-7装置电子回旋辐射系统接收天线改进

为了提高HT-7装置上等离子体电子回旋辐射(ECE)超外差诊断系统的极向分辨率,根据高斯光学原理,分析了诊断系统天线的改进方案。优化了天线的圆形角锥喇叭尺寸和凸透镜参数以及在装置上的相对位置,使天线接收到的等离子体ECE异常模二次谐波辐射的高斯光束束半径只有30mm左右,能量的高斯光学性质损失不大于13%。     

High Closed Loop Correction Accuracy with a Liquid Crystal Wavefront Corrector

We investigate the accurate control of a liquid crystal wavefront corrector. First, the Gamma correction technique is adopted to amend the nonlinear phase modulation. Then, the control method and wavefront reconstruction are considered. Lastly, a closed loop correction experiment is carried out and a high correction accuracy is obtained with peak to valley （PV） of 0.08λ （λ = 632.8 nm）, the wavefront phase rms 0.015λ, as well as the Strehl ratio of 0.99. The diffraction-limited resolution is achieved.     

HL—1M装置LHCD系统双管运行及长脉冲实验

通过对ＨＬ－１Ｍ装置的ＬＨＣＤ工程系统的微波耦合天线,传输线,高压调制电源,激励电源,辅电源,冷却系统的改进,实现了双管并联动行和单管长脉冲输,双管输出微波功率８５０ＫＷ,单管长脉冲宽度１０５０ｍｓ,耦合效率达到８５％     

薹草属少花薹草组（莎草科）的果囊形态及其系统学意义

用扫描电镜观察了少花薹草组Carex sect. Paniceae （莎草科） 26种3变种的果囊形态和微形态特征。结果表明：（1）果囊形状（喙除外）为倒卵球形、椭球形或卵球形,均为钝三棱状,果囊长度为1.99～7.27 mm,喙多弯曲（仅1种C. striatula果囊的喙直立）,喙急缩或渐缩,喙长与果囊长度的比值为1/8～1/2,表皮细胞多明显隆起,极少数隆起不明显,且多数性状种内保持稳定;（2）喙口形态分斜截、平截、微二齿和二齿4类,且在种内有变异,如C. arakiana、线柄薹草C. filipes、丝柄薹草C. rouyana、C. purpurifera;(3)可根据果囊长度和喙的收缩情况区分部分近缘种,如线柄薹草与少囊薹草C. egena、浙江薹草C. zhejiangensis与显舌薹草C. macroglossa;(4)果囊长度、喙长与果囊长度的比值在sect. Paniceae s.s.与sect. Laxiflorae 2组间有显著差异,对两组的界定有一定价值;（5）被视为组或亚属重要分类性状的果囊横切形状（三棱状或双凸状）在界定少囊薹草组与相关组时无意义,果囊...     

热裂解气相色谱法测定动物源性食品中敌百虫残留量

通过对热裂解气相色谱及气-质联用技术测定动物源性食品中敌百虫的探讨,建立了气相色谱进样口裂解产物的检测方法,并确定了气相色谱的主要分析条件(进样口280℃,DB-225毛细管色谱柱及FPD检测器)。样品前处理结合动物源性食品的特点,采用V(乙腈)∶V(水)=9∶1提取,乙酸锌水解除酯,并利用三氯化碳相转移的方式,建立了一套前处理方法。检测方法的回收率在80.7%~96.5%之间,RSD<5.5%,线性相关系数为0.9991,检出限为0.02mg/kg。该方法是按照我国关于兽药残留分析方法要求建立的,适合进出口及日常动物源性食品中敌百虫残留量的检测。     

A concise review of Rydberg atom based quantum computation and quantum simulation

Quantum information processing based on Rydberg atoms emerged as a promising direction two decades ago.Recent experimental and theoretical progresses have shined exciting light on this avenue.In this concise review,we will briefly introduce the basics of Rydberg atoms and their recent applications in associated areas of neutral atom quantum computation and simulation.We shall also include related discussions on quantum optics with Rydberg atomic ensembles,which are increasingly used to explore quantum computation and quantum simulation with photons.