基于EPICS的CSRe束流诊断控制系统升级

兰州重离子加速器(HIRFL)冷却存储环的实验环（CSRe）提供高品质的束流用于高精度的质量测量、原子物理等实验研究,实现束流参数的准确测量是进行物理实验的前提保障。目前,CSRe加速器控制系统已升级为EPICS架构。介绍了基于EPICS的束流诊断控制系统现状,并利用升级后的控制系统测量了束流相关参数。其中,束流位置系统能够测量注入束流的逐圈位置信息,测量结果发现束流在注入过程中存在一定程度的震荡,影响注入效率。流强测量系统通过高分辨的数据采集卡实现对DCCT信号的精确测量,同时增加了D事例触发功能。升级后的控制系统,可以实现束流参数的测量,并集成于加速器控制系统的EPICS CSS界面。     

Relativistic configuration interaction calculations for the K α X-ray transitions of Co XV to Co XXVI ions

Relativistic configuration interaction calculations with the inclusion of the Breit interaction, quantum electrodynamics (QED) and finite nuclear mass corrections have been carried out in the extended optimal level scheme using multiconfiguration Dirac-Fock wave functions on the wavelengths, electric dipole rates, oscillator strengths and line strengths of cobalt ions with a single vacancy in the K shell. The calculated values are compared with the other available data on He-like to Be-like cobalt and are found to be in very good agreement with them. This confirms the present calculations. We predict new data for several levels where no other theoretical and/or experimental results are available. These data provide reference values for level lifetimes, charge state distribution and the average charge of cobalt plasmas.     

基于AOTF的成像光谱仪及其在同色异谱目标鉴别中的应用

为了同时获得同色异谱目标的光谱信息和空间分布信息,设计了基于声光可调谐滤波器(acousto-optic tunable filter, AOTF)的成像光谱仪,主要包括前置成像透镜组、AOTF滤光成像模块、AOTF驱动器、CCD图像检测器、图像采集卡和计算机。在计算机的控制下,实现波长的快速扫描,获取每个设定波段下的灰度图像,构建一个光谱图像立方体,因此可以获得图像中任意一点的光谱信息。所设计的成像光谱仪,光谱范围为550 ～1 000 nm,光谱分辨率2.6 nm(@632 nm),光谱扫描速度快,任意两个波长之间的切换时间小于80 μs,整个仪器无机械运动部件,功耗低,抗振能力强。利用该仪器对真假玫瑰花进行了鉴别试验,对涂改物证进行了信息复原实验,并成功地辨别出真假玫瑰花和复原出涂改物证,证实了该成像光谱仪具有优异的同色异谱目标鉴别本领,在同色异谱物质的鉴别上具有广阔的应用前景。     

U(1) symmetry in the current algebra and N-fermionic massless Thirring model

Local U(1) symmetry in current algebra constructed by fermions has been found. The symmetry is related to the simplest q-deformation of N-fermions. We give the physical interpretation through the N-fermionic massless Thirring model. The Bethe ansatz wavefunction is also given.     

Polymerization of aniline in the galleries of layered HNbMoO6

Insertion of aniline molecules and subsequent polymerization using FeCl₃ as an oxidizing agent were examined in the layers of rutile-type HNbMoO₆. Although the polyaniline/host ratio was variable depending on the amount of intercalated aniline before polymerization, the interlayer spacing was constant as 6.3 Å regardless of the ratios. Comparison of FT-IR and FT-Raman spectra for (PANI)_yNbMoO₆ (0.26≤y≤0.64) clearly showed that both quinoid and benzenoid forms exist in the galleries of inorganic host. IR and Raman active modes of extracted PANI from the matrix were quite similar to those of emeraldine salt.     

可实现防碰撞通信的新型声表面波温度传感器

针对多声表面波传感器系统中各传感器信息读取时会产生通信碰撞的问题,提出了一种可实现防碰撞通信的新型声表面波温度传感器;通过分析声表面波温度传感器的回波脉冲信号,将沃尔什码作为编码内容实现了多声表面波温度传感器系统中各传感器的正交编码;将传感器对应的匹配信号与系统回波信号进行互相关运算,提取了系统中各传感器的感测温度信息,达到了防碰撞通信的目标;该传感器兼顾编码效率和加工工艺两方面要求,简化感测信息提取的复杂程度;仿真实验验证了上述理论的正确性。     

高能光源束流位置探测器支撑架结构优化设计

从热稳定性和振动稳定性两个角度出发,优化设计得到了超高稳定的刚性支撑架结构;通过ANSYS有限元模态分析,验证了结构的热膨胀变化量和特征频率;采用混凝土二次灌浆方法对支撑架进行地面固定和特征频率测试,结果表明,支撑架结构的特征频率达到61.9 Hz、振动幅值小于30 nm,均满足设计要求。最后采用动态刚度测试方法,得到混凝土二次灌浆层的主要刚度值,进一步验证支撑架结构优化结果的准确性。     

等离子体表面梯度硅沉积对环氧树脂电气性能的影响

环氧树脂作为常见的绝缘材料,在高压直流电场作用下易在其表面积累电荷,发生电场畸变,导致材料绝缘性能下降,影响电力系统运行可靠性。为改善气固界面的电荷特性和绝缘性能,在大气压等离子体射流技术的基础上,对环氧树脂表面进行等离子体梯度硅沉积处理。对改性前后环氧树脂表面理化特性、表面电导率、表面电荷消散和沿面耐压特性进行了多参数测量。实验结果表明,梯度改性对材料表面的物理形貌和化学组分均有明显影响,不同区域的电导率实现了梯度分布,加快了表面电荷消散速度,表面陷阱能级变浅;梯度改性后的样品沿面闪络电压提升幅度可达30.16%。通过等离子体表面梯度硅沉积处理能够改善环氧树脂表面电气性能,在高压直流设备的绝缘设计方面具有广阔的应用前景。     

LEO空间目标的非协同共视观测及初轨确定

测角数据的初轨确定(IOD)是通过光学观测技术进行空间目标编目的 关键,然而对于低地球轨道(LEO)空间目标,地基光学观测所获得的数据弧长较短且不包含距离信息.因此,在进行IOD时,所得轨道的误差往往较大,难以应用于进一步的工作中.针对上述问题,研究了LEO空间目标的非协同共视观测技术及其初轨确定,并基于统计学提出了一...     

Bulk viscosity for interacting strange quark matter and r-mode instability windows for strange stars

We investigate the bulk viscosity of strange quark matter in the framework of the equivparticle model,where analytical formulae are obtained for certain temperature ranges,which can be readily applied to those with various quark mass scalings.In the case of adopting a quark mass scaling with both linear confinement and perturbative interactions,the obtained bulk viscosity increases by 1-2 orders of magnitude compared with those in bag model scenarios.Such an enhancement is mainly due to the large quark equivalent masses adopted in the equivparticle model,which are essentially attributed to the strong interquark interactions and are related to the dynamical chiral symmetry breaki ng.Due to the high bulk viscosity,the predicted damping time of oscillatio ns for a can on ical 1.4 M⊙ strange star is less than one millisecond,which is shorter than previous findings.Consequently,the obtained r-mode instability window for the canonical strange stars well accommodates the observational frequencies and temperatures for pulsars in low-mass X-ray binaries(LMXBs).