紫外-可见光双通道拉曼光谱仪光学设计

紫外拉曼光谱技术具有高强度拉曼散射、无荧光干扰的特点;可见光拉曼光谱技术可实现低波数、高分辨率探测。为兼具两种激发波长的优势,设计了一款对称分布的双Czerny-Turner光路聚焦于一个探测器的双通道拉曼光谱仪。通过元器件的选型和初始结构的计算,在不增加多余元器件的情况下,对弧矢方向像散进行补偿,避免了像面上的能量损失。配合Zemax软件对双通道光谱分别进行建模优化,最终实现了对400~5000 cm^-1（266 nm激发）和50~3500 cm^-1（633 nm激发）两段光谱的同时探测。均方根半径、点列图和调制传递函数等评价指标有效验证了设计的合理性和可行性。结果表明,两套拉曼光谱仪分别可达8 cm^-1和5 cm^-1分辨率,本设计具有高分辨率、低波数、多波长激发、集成化等优势。     

高分辨宽光谱微型拉曼光谱仪的设计

为了同时满足光谱分辨率、光谱范围、探测器(CCD)上光谱信号覆盖区域要求,提出一种基于Czerny-Turner(CT)结构拉曼光谱仪的综合设计方法,通过Zemax软件采用逐步手动调节光栅倾斜,自动优化聚焦镜、柱面镜以及CCD间倾角和距离的方式,设计出全波段光谱分辨率优于4cm-1,光谱波数范围为80~3 967cm~(-1),光学结构尺寸为90mm×130mm×40mm的微型拉曼光谱仪。     

多波长激发高分辨率微型拉曼光谱仪设计

针对不同激光波长激发测试样品所需拉曼光谱范围的差异性问题,同时为了保证拉曼光谱仪的小型化及高分辨率需求,提出一种以Czerny-Turner光路结构为基础的微型拉曼光谱仪,通过Zemax光学设计软件对光谱仪的准直镜、聚焦镜、柱面镜、光栅以及CCD的倾角及距离进行了优化。该仪器激光波长为633 nm,光谱范围为640～800 nm。进一步优化光栅旋转角度并配合聚焦镜,可使此光学系统同时适用于激光波长532 nm、光谱范围540～650 nm和激光波长785 nm、光谱范围790～1 000 nm两个波段。拉曼光谱仪分辨率为0.1 nm,该光谱仪在保证高分辨率的情况下解决了不同波段范围光学结构差异性大而导致光机设计很难整合在一起的问题。     

基于非球面反射镜的高分辨KB显微成像系统设计

为了突破球面反射镜面形对传统Kirkpatrick-Baez（KB）显微镜空间分辨率的限制,建立了一种非球面KB显微成像系统的光学设计方法。利用椭圆柱面反射镜代替球面镜,通过几何关系计算出反射镜参数的数学表达式,结合主要光学结构参数对空间分辨率影响的定量分析,提出了一组适用我国现阶段强激光装置的非球面KB显微镜的结构参数,并在实验室内开展背光成像实验。实验结果表明,在中心视场,其空间分辨率优于2 μm,在200 μm的视场范围内,空间分辨率优于5 μm,集光立体角可达1.3×10⁻⁶sr。非球面KB显微镜有效提高了KB显微镜中心视场分辨率,符合内爆靶减速阶段的高分辨诊断需求。     

低强度中子流电视摄像系统

本文介绍了低强度(3～4×10³n/cm²s)中子流电视摄像系统。它利用SEC摄像机独特的积累性能,将一个用人眼直接观察什么也看不见的、不连续光点的低照度(1×10^-4Lx)中子流像转换成一个能在监视器上观察的可视图像。     

极紫外太阳望远镜成像质量检测系统设计

为了在实验室模拟空间环境,检测极紫外太阳望远镜成像质量,提出了由激光等离子光源、Newton型准直光管系统、背照射CCD相机、真空系统等组成的工作波段为17~30 nm的极紫外准直光管检测系统,给出了详细的物理分析、光学设计和真空系统设计方法和结果。真空实验测试结果表明,系统在80 min内,真空度即可达到5×10^-4 Pa的设计指标,满足极紫外波段检测太阳望远镜的要求。     

半导体载流子分布的太赫兹近场显微表征

基于自建的太赫兹散射型扫描近场显微镜系统（THz s-SNOM）,研究了其在显微表征半导体载流子浓度分布中的应用。对基于半导体硅的静态随机存取存储器（SRAM）的纳米结构进行了近场显微成像测量,并采用可见光调控本征硅样品表面的载流子浓度,实现了不同浓度（10¹⁴～10¹⁷ cm⁻³）光生载流子的近场检测。结果表明,此THz s-SNOM能够对半导体微纳结构的载流子分布进行高空间分辨率的显微表征,测量结果与基于偶极子模型的计算结果具有较好的吻合度。     

Fizeau激光波长计测量脉冲激光波长

详细讨论了采用单片机控制的Fizeau波长计测量脉冲激光波长的两种方法,包括脉冲激光同步测量方法与软件判别捕捉方法,文章最后给出了系统的测量结果,其测量精度与测量连续激光相同,即绝对精度<10^-6,分辨率<10^-7.     

Henke型软X射线源的研制与测试

本文叙述了Henke型软X射线源的主要特点及研制、测试工作.我们研制的Henke源采用棱形靶、线焦点、可拆卸式结构.最大阳极电流可达100mA.本文还介绍了70m真空装置上的软X射线接收实验.终端计数率>3×10⁴/s·cm².     

Mg(PO3)2-BaF2-AlF3系统玻璃的振动谱研究

应用红外及拉曼光谱研究了Mg(PO₃)₂-BaF₂-AlF₃系统氟磷玻璃的结构特征.证实了双键氧(P=O)及由Al(O.F)₄四面体和P(O.F)₄四面体所混合构成的网络结构存在于玻璃之中.在拉曼光谱中,V_Ba-F、V_Mg-F和V_Al-F振动吸收峰分别出现在480-510cm^-1、530-550cm^-1和580cm^-1处.根据红外及拉曼光谱的结果得出:随系统中氟化物含量的增加,玻璃结构逐渐由聚磷酸盐转变为焦磷酸盐和一氟正磷酸盐混合物,同时双键氧(P=O)消失.     

Minimal Realization of Linear Graph Models for Multi-physics Systems

An engineering system may consist of several different types of components,belonging to such physical"domains"as mechanical,electrical,fluid,and thermal.It is t...     

INTEGRAL EQUATION METHOD＇S APPLICATION IN HOLE-EDGE STRESS OF COMPOSITE MATERIAL PLATE WITH DIFFERENT SHAPED HOLES

The strength of composite plate with different hole-shapes is always one of the most important but complicated issues in the application of the composite material. The holes will lead to mutations and discontinuity to the structure. So the hole-edge stress concentration is always a serious phenomenon. And the phenomenon makes the structure strength decrease very quickly to form dangerous weak points. Most partial damage begins from these weak points. According to the complex variable functions theory, the accurate boundary condition of composite plate with different hole-shapes is founded by conformal mapping method to settle the boundary condition problem of complex hole-shapes. Composite plate with commonly hole-shapes in engineering is studied by several complex variable stress fimction. The boundary integral equations are founded based on exact boundary conditions. Then the exact hole-edge stress analytic solution of composite plate with rectangle holes and wing manholes is resolved. Both of offset axis loadings and its influences on the stress concentration coefficient of the hole-edge are discussed. And comparisons of different loads along various offset axis on the hole-edge stress distribution of orthotropic plate with rectangle hole or wing manhole are made. It can be concluded that hole-edge with continuous variable curvatures might help to decrease the stress concentration coefficient; and smaller angle of outer load and fiber can decrease the stress peak value.     

Non-monotonic material contrast in scanning ion and scanning electron images

30 keV Ga⁺ focused ion beam induced secondary electron (iSE) imaging was used to determine the relative contrast between several materials. The iSE signal compared from C, Si, Al, Ti, Cr, Ni, Cu, Mo, Ag, and W metal layers does not decrease with an increase in target atomic number Z₂, and shows a non-monotonic relationship between contrast and Z₂. The non-monotonic relationship is attributed to periodic fluctuations of the stopping power and sputter yield inherent to the ion–solid interactions. In addition, material contrast from electron-induced secondary electron (eSE) and backscattered electron (BSE) images using scanning electron microscopy (SEM) also shows non-monotonic contrast as a function of Z₂, following the periodic behavior of the stopping power for electron–solid interactions. A comparison of the iSE and eSE results shows similar relative contrast between the metal layers, and not complementary contrast as conventionally understood. These similarities in the contrast behavior can be attributed to similarities in the periodic and non-monotonic function defined by incident particle–solid interaction theory.     

Application of Feature Extraction through Convolution Neural Networks and SVM Classifier for Robust Grading of Apples

This paper proposes a novel grading method of apples,in an automated grading device that uses convolutional neural networks to extract the size,color,texture,an...     

分布动态载荷识别的抗噪处理

针对正交多项式频域法在用多种响应对矩形薄板进行载荷识别中抗噪性较差的问题,综合运用平均法、矩阵预处理和奇异值截断法等方法对之进行改善,并引入空间映射的思想,将该方法的应用范围拓展为复杂的模型.利用仿真算例,证实了该方法具有较好的抗噪性.     

基于MELTAC-N平台的核电厂安全级DCS环网研究与测试

针对工程实践中环网通讯相关问题的处理缺乏理论基础及国产化安全级DCS平台的开发缺乏成熟经验借鉴问题,对基于MELTAC-N平台核电厂安全级DCS环网的软硬件实现进行了研究。提出了安全级DCS环网双环网冗余设计、光切换开关设计等硬件设计方法,以及以RPR协议为基础,采用全数据收发策略的软件设计方法。在CPR1000安全级DCS平台上对安全级DCS环网的可靠性及实时性进行了评价,并进行了容错能力、响应时间及响应时间稳定性测试验证实验。结果表明,基于MELTAC-N平台安全级DCS环网软硬件设计具有较好的容错能力及响应时间稳定性。     

Short-Term Relay Quality Prediction Algorithm Based on Long and Short-Term Memory

The fraction defective of semi-finished products is predicted to optimize the process of relay production lines, by which production quality and productivity ar...     

End-to-End Multiview Gesture Recognition for Autonomous Car Parking System

The use of hand gestures can be the most intuitive human-machine interaction medium.The early approaches for hand gesture recognition used device-based methods....     

The laboratory simulation of abrasive wear

Abrasive wear has long been recognised as one of the most potentially serious tribological problems facing the operators of many types of plant and machinery; several industrial surveys have indicated that wear by abrasion can be responsible for more than 50% of unscheduled machine and plant stoppages. Locating the operating point of a tribological contact in an appropriate operational ‚map’︁ can provide a useful guide to the likely nature and origins of the surface degradation experienced in use, though care must be exercised in choosing the most suitable parameters for the axes of the plot. Laboratory testing of materials and simulations of machine contacts are carried out for a number of purposes; at one level for the very practical aims of ranking candidate materials or surface hardening treatments in order of their wear resistance, or in an attempt to predict wear lives under field conditions. More fundamentally, tests may be aimed at elucidating the essential physical mechanisms of surface damage and loss, with the longer term aim of building an analytical and predictive model of the wear process itself. In many cases, component surface damage is brought about by the ingress of hard, particulate matter into machine bearing or sealing clearances. These may be running dry although, more usually, a lubricant or service fluid is present at the interface. A number of standardised wear test geometries and procedures have been established for both two- and three-body wear situations, and these are briefly described. Although abrasive wear is often modelled as following an ‚Archard’︁ equation (i.e. a linear increase in material loss with both load and time, and an inverse dependence on specimen hardness) both industrial experience and laboratory tests of particularly lubricated contacts show that this is not always the case: increasing the hardness differential in an abrasively contaminated lubricated pair may not always reduce the rate of damage to the harder surface.     

ANGULAR DISTORTION ALLOWABLE VALUE AND ASSESS METHOD OF WELD ON COKE TOWER

A graph as the new engineering method for estimate the safety of bulging deformation of coke tower is proposed. Through stresses analysis of circumferential weld of coke tower and comparing the stresses produced by pressure with heat stress of steady state, residual stress, bending stress produced by both itself weight and wind loads, it showed that the stresses produced by pressure on the angle distortion are the main factor of equivalent stress of the combined stress. After comparing four kinds of stress controlling conditions, the relation to stress with depth of angular distortion, grade of curvature of angular distortion and half of region of angular distortion has been inferred. Graph of deformation allowable value of coke tower for different condition by angular distortion and half of region of angular distortion has been plotted. The five steps for its engineering use have been explained. The lighter the grade of curvature is, the larger of bulge allowance, may be, and the bigger of depth of angular distortion may pose too. For the coke tower with a popular structure of Dg 5 400 mm×28 mm, the result by graph is nearly more than the result of two formulas formed by other research, the error is less than 7.0%. But, the graph can be easily applied to different size of angular distortion.