酸性品红褪色光度法测定痕量铁(Ⅲ)

基于Fe(Ⅲ)可使酸性品红氧化褪色,建立了一种褪色光度法测定铁的新方法,该方法线性范围为0-8.25μg/mL,检出限为3.72×10-4μg/mL.用于水样中Fe(Ⅲ)含量的测定,回收率在90%-100%.     

低温翅片管换热器的传热试验研究

为了研究翅片管换热器在低温工况下的传热性能,进行了翅片管汽化器的气化试验。采用低温热电偶连续测量翅片管汽化器8个不同位置的温度,得到8条温度曲线。分析曲线表明气化过程可归结为非稳态与稳态两个阶段,并经历液相、汽液两相及气相三个传热区。试验结果为同类换热器的分段设计提供了依据。     

抽运-检测型非线性磁光旋转铷原子磁力仪的研究

报道了一种抽运-检测型的非线性磁光旋转铷原子磁力仪.其原理是线偏振光通过处于外磁场环境中被极化的原子介质后,由于原子对线偏振光中左、右圆偏成分不同的吸收和色散,导致光的偏振方向会产生与磁场相关的转动.分析了该磁力仪的工作原理,并测试了它对不同磁场大小的响应.测试结果表明,磁力仪测量范围为100—100000 nT,极限灵敏度为0.2 p T/Hz~(1/2),磁场分辨率为0.1 p T.进一步研究了不同磁场下原子系综极化态的横向弛豫时间,讨论了原子磁力仪高磁场采样率的获得方法.本文的原子磁力仪在5000—100000 n T的磁场测量范围内磁场采样率可实现1—1000 Hz范围内可调,能够测量低频的微弱交变磁场.本文的研究内容为大磁场测量范围、高灵敏度、高磁场采样率的原子磁力仪研制提供了重要参考.     

Optical and electrical properties of aluminum-doped ZnO thin films grown by pulsed laser deposition

Transparent aluminum-doped zinc oxide (AZO) thin films were deposited on quartz glass substrates by pulsed laser deposition (PLD) from ablating Zn-Al metallic targets. The structural, electrical and optical properties of these films were characterized as a function of Al concentration (0-8 wt.%) in the target. Films were deposited at a low substrate temperature of 150 °C under 11 Pa of oxygen pressure. It was observed that 2 wt.% of Al in the target (or 1.37 wt.% of Al doped in the AZO film) is the optimum concentration to achieve the minimum film resistivity and strong ultraviolet emission. The presence of Al in the ZnO film changes the carrier concentration and the intrinsic defects.     

武器装备维修性验证试验方法研究

近年来,我军开始推行武器装备三级维修保障体系向两级维修保障体系转变的维修体制改革。武器装备的维修性是实施装备两级维修保障体制改革的关键,在生产定型阶段对其进行维修性验证试验很有必要。为了进一步完善维修性验证试验方法,以适应维修体制改革的需求,分别对开展武器装备维修性验证试验工作的时机、内容、方法与流程进行了概述;在分析了当前维修性验证试验方法特点的基础上,重点对维修性验证试验工作中的试验方法的选取、样本量确定及样本分配、故障模拟及注入三个关键技术及研究现状进行了总结与归纳;通过对试验关键技术的研究,分析了当前开展维修性验证试验工作存在的问题,对进一步开展维修性验证试验方法研究的内容及方向进行了展望。     

机载北斗/GPS/SINS组合导航系统软硬件设计

针对单一导航导航系统在导航精度、稳定性、设备成本以及导航信息完备性等方面的局限性,设计了卫星导航/惯性导航组合导航系统。针对GPS导航系统受制于人及北斗导航系统发展尚不完善的特点,提出了基于北斗/GPS/SINS的军用机载组合导航系统软硬件设计。搭建了北斗/GPS/SINS组合导航系统硬件平台,采用基于不确定度的加权平均数据融合算法提高组合导航系统的导航可靠性和准确性。仿真结果表明,该组合导航系统稳定性好,可靠性高,定位准确。     

基于微波相位补偿的56 km高精度光纤微波频率传递

报道了实验室内56 km光纤微波频率传递的实验研究,在56 km的传递距离上实现了1.8×10-15/s,4×10-18/104s的传递稳定度.系统通过环回法比较往返传递的微波信号相位获得链路上的相位扰动量,并实时控制本地发射端的微波发射信号相位实现预补偿.在环回往返传递的不同方向上,系统方案采用不同频率的微波调制信号...     

Quantum Fisher information of a qubit-qutrit system in Garfinkle–Horowitz–Strominger dilation space–time

We investigate the quantum Fisher information(QFI) of a qubit-qutrit system in the background of Garfinkle–Horowitz–Strominger dilation black hole. After deriving the analytical expression of the QFI, we examine its dynamics with respect to the dilation parameter D and the state parameter γ of the system. Our results show that the QFI for the estimation of γ is a fixed value,which is independent of the parameters D and γ. And the QFI for the estimation of D varies with the parameters D and γ. Additionally, we propose an effective strategy to steer the QFI by introducing weak measurement reversal. We find that the QFI can be remarkably enhanced by adjusting the appropriate reversing measurement strengths. Our findings might provide some useful insights for the study on parameter estimation of hybrid systems in the framework of relativity theory.     

Theoretical research on terahertz wave generation from planar waveguide by optimized cascaded difference frequency generation

A novel scheme for high-efficiency terahertz(THz)wave generation based on optimized cascaded difference frequency generation(OCDFG)with planar waveguide is presented.The phase mismatches of each-order cascaded difference frequency generation(CDFG)are modulated by changing the thickness of the waveguide,resulting in a decrement of phase mismatches in cascaded Stokes processes and an increment of phase mismatches in cascaded anti-Stokes processes simultaneously.The modulated phase mismatches enhance the cascaded Stokes processes and suppress the cascaded anti-Stokes processes simultaneously,yielding energy conversion efficiencies over 25%from optical wave to THz wave at 100 K.     

大白鼠脑中风模型的核磁共振成像(英文)

核磁共振成像现今已经成为临床神经影像的常规工具.在诊断、评估和监测中风从急性到慢性的各个阶段的脑组织的变化过程中,核磁共振成像扮演了一个重要的角色.该综述提供了多种核磁共振成像方法的描述,以及选择性地展示了作者在美国亨利福特医院神经科核磁共振成像实验室所获得的大白鼠栓塞中风模型的核磁共振成像研究成果.