Operando measurement of lattice deformation profiles of synchrotron radiation monochromator

This study presents a new method for characterizing the thermal lattice deformation of a monochromator with high precision under service conditions and first reports the operando measurements of nanoscale thermal lattice deformation on a double-crystal monochromator at different incident powers.The nanoscale thermal lattice deformation of the monochromator first crystal was obtained by analyzing the intensity of the distorted DuMond diagrams.DuMond diagrams of the 333 diffraction index,sensitive to lattice deformation,were obtained directly using a 2D detector and an analyzer crystal orthogonal to the monochromator.With increasing incident power and power density,the maximum height of the lattice deformation increased from 3.2 to 18.5 nm,and the deformation coefficient of the maximum height increased from 1.1 to 3.2 nm/W.The maximum relative standard deviation was 4.2%,and the maximum standard deviation was 0.1 nm.Based on the measured thermal deformations,the flux saturation phenomenon and critical point for the linear operation of the monochromator were predicted with increasing incident power.This study provides a simple solution to the problem of the lower precision of synchrotron radiation monochromator characterizations compared to simulations.

Design and implementation of the monochromator shielding for the cold neutron spectrometers XINGZHI and BOYA

An innovative monochromator shielding is designed and implemented for the cold neutron spectrometers XINGZHI and BOYA operated by Renmin University of China at China Advanced Research Reactor.Via Monte Carlo simulations and careful mechanical designs,a shielding configuration has been successfully developed to satisfy safety requirements of below 3μSv/h dose rate at its exterior,meanwhile fulfilling space,floor load and nonmagnetic requirements.Composite materials are utilized to form the sandwich-type shielding walls:the inner layer of boron carbide rubber,the middle layer of steel-encased lead and the outer layer of borated polyethylene.Special-shaped liftable shielding blocks are incorporated to facilitate a continuous adjustment of the neutron energy while preventing radiation leakage.Our work has demonstrated that by utilizing composite shielding materials,along with the sandwich structure and liftable shielding blocks,a compact and lightweight shielding solution can be achieved.This enables the realization of advanced neutron scattering instruments that provide expanded space of measurement,larger energy and momentum coverage,and higher flux on the sample.This shielding represents the first of its kind in neutron scattering instruments in China.Following its successful operation,it has been subsequently employed by other neutron instruments across the country.

Cooling of double crystal monochromator with sagittal focus at SSRF

In SSRF, the design of 1st crystal cooling geometry of double crystal monochromator with sagittal focus is mainly reported by China. Our simulation indicates that the broadening of the full width at half maximum of the rocking curve of the double crystal monochromator induced by the heat load is about 3.7 μrad, and is in agreement with the experimental value of 5 μrad. Our scheme showed that the photon flux is reliably linear with electron current of the storage ring, which is extracted from the monochromator.

Implementation of effective control system for variable-included angle plane-grating monochromator

The variable-included angle plane-grating monochromator is a homemade key equipment of the scanning transmission X-ray microscopy (STXM) beamline at Shanghai Synchrotron Radiation Facility (SSRF).Monochromatic light of various wavelengths is achieved by an effective control system that handles the rotation of the plane mirror and plane grating mounted in a high vacuum chamber.M511.DDB made by PI Corp.is used as motion stage which has a DC servo motor controlled by a C862 controller based on RS232 protocol.The software platform of STXM is EPICS,so the local control functions are implemented by LabVIEW program to satisfy physics control.For the remote control functions,the program is integrated into EPICS with ShareMemoryIOC.Experimental tests show that the repeat precision of motion control is less than 0.2μm,which meets the control demand.

浅析富士monochrome instax mini

本文对富士monochrome instax mini的微观结构进行了分析,并对涂层结构和影像形成机理进行了剖析。结果表明:富士monochrome instax mini含有多个功能涂层,结构复杂,采用正性乳剂技术、特殊显影加工技术、染料释放扩散技术以及染料固定等技术手段,通过染料的扩散叠加形成黑白影像。制作monochrome instax mini需要掌握彩色一次成像相关技术,制作难度偏大。

C-T曲线通用性分析和试验研究

提出了疲劳寿命预腐蚀影响系数曲线(C- T 曲线)通用性分析的 C值直接对比法和C -T 曲线参数统计对比法,并进行相关试验研究,得到了 C -T 曲线和载荷谱、应力水平以及裂纹尺寸基本无关的结论。C- T曲线是进行腐蚀条件下飞机结构疲劳寿命评定和分析的基础,为验证分析 C- T 曲线和载荷谱、应力水平以及裂纹尺寸的相关性,从C的定义和分布规律出发,提出了 C值直接对比法和C -T 曲线参数统计对比法,近似谱、不同恒幅应力水平以及不同指定裂纹尺寸下的预腐蚀疲劳寿命数据均表明了 C- T 曲线基本具有通用性;并进行了某型飞机结构主梁模拟试件在随机谱及恒幅谱下的预腐蚀疲劳试验,试验结果同样验证了上述结论,从而说明了C- T 曲线的通用性。

非平行光束光栅照明C-T成像光谱仪消像散研究与设计

切尔尼-特纳(Czerny-Turner,C-T)光谱仪是光栅光谱仪中常用的光谱仪器。其结构紧凑,无非球面镜,常被用于单色仪和光谱辐射计中。对于成像光谱仪,像散是影响其空间分辨和光能利用的主要像差。就非平行光束光栅照明像散校正方法进行了理论分析和实验验证,提出会聚和发散光栅照明C-T成像光谱仪都可以进行像散校正,其根本取决于光栅入射角和衍射的余弦平方比大于或小于1,大于1对应发散照明消像散,小于1则对应会聚照明消像散。

一种新型C-T变换电路

一种新型Ｃ┐Ｔ变换电路湖北华中精密仪器厂（４４３３０４）胡学红郑建国电容—时间间隔（Ｃ－Ｔ）变换是电容数字化测量技术的核心环节。本文提出的Ｃ－Ｔ变换方案基于双斜率积分原理，其组成电路简单、准确度高，同时具有很强的抗共模干扰性能。该Ｃ－Ｔ变换电路较容易...

苯妥英钠C-T曲线的双峰现象

报道5例健康志愿者单剂量po苯妥英钠200mg,在0.5,1,2,4,6,8,12,16,24h时,取静脉血,采用荧光偏振免疫法测定其血药浓度.结果发现5例志愿者的C-T曲线均有双峰现象.

佳灵JP6C-T9系列变频器RS485-CAN转换器的设计

针对佳灵JP6C-T9系列变频器通讯功能上的缺陷,在对可靠性、转换效率、成本以及体积进行充分考虑的基础上设计了一种适合于这一系列变频器的RS485-CAN转换器,并介绍了转换器的硬件设计和软件设计方法.

硅MOS结构C-t瞬态分析中产生区宽度的新模型

在分析已有的半导体表面产生区宽度模型的基础上 ,提出了可用于产生寿命直接计算且精度较高的产生区宽度新模型 ,它也可以看作是对 Zerbst模型的一种修正 .新模型的标准偏差小于 Pierret模型的标准偏差 .实验数据的分析表明 ,用该模型得到的产生寿命值与

一种基于C-T空间数字势场的机器人避碰规划方法

提出一种基于C-T(configuration-time)空间数字势场的机器人避碰路径规划方法,通过构造一种栅格化的C-T空间数字势场,根据数字势场中的排斥势和吸引势,利用C-T空间离散路径点的插值方法,实现机器人对运动障碍物的避碰.通过一个2连杆机器人臂的避碰仿真实验研究,表明了该方法具有较高的计算效率,避免了一般避碰算法的大量C空间显式计算,能够适用于机器人的动态环境路径规划.

C-T/T值用于儿童胸腺X线测量上的意义

本文应用 Gewolb 提出的测量胸腺的方法测量185例0～15岁正常儿童和44例肺炎儿童胸片上的 C-T/T 值,碍出正常儿童 C-T/T 的均值为0.283±0.004(M±SEM),0.35为其上限,可作为胸腺肥大的指征。通过分析可看出 C-T/T 值随年龄增加而变小,3岁内的变化幅度明显;而性别之间,正常与肺炎组儿童之间无显著差异。

一种基于集成扫描光栅微镜和改进型非对称式C-T结构的微型近红外光谱仪

近红外光谱分析技术在航空航天、生物医药、环境检测、食品安全等众多领域均有广泛应用。高性能、微型化、低成本近红外光谱仪是制约基于近红外连续光谱分析的微小型检测装备发展的主要瓶颈,是当前光谱仪发展的主要研究方向。提出了一种基于微光机电系统(Micro-optical electro-mechanical system,MOEMS)集成扫描光栅微镜和改进型非对称式切尼-特纳(Czerny-Turner,C-T)光学结构的微型近红外光谱仪系统结构,分析了光谱仪系统和集成扫描光栅微镜的工作原理,基于光栅相关参数和光谱仪性能指标要求确定了集成扫描光栅微镜最大扫描角度。分析了改进型非对称式C-T初始光学结构像差,基于ZEMAX光学设计平台完成了光谱仪光学系统的仿真和优化设计,确定了系统关键参数。仿真分析了平凸柱面透镜对改进型非对称式C-T光学结构系统分辨率、检测灵敏度等性能参数的影响。基于仿真优化结果,完成了微型近红外光谱仪机械结构设计、加工与装调,搭建实验平台完成了光谱仪相关性能参数测试。结果表明,设计的基于MOEMS集成扫描光栅微镜和改进型非对称式C-T光学结构的微型近红外光谱仪,采用重庆大学自主研发的谐振频率为677.1 Hz的MOEMS集成扫描光栅微镜来实现同步扫描和分光,0.8 ms时间内即可完成一次波长范围800~1800 nm的光谱测量,光谱准确性与国外品牌光谱仪比较无明显差异,光谱整体分辨率半峰全宽(FWHM)≤11 nm,波长稳定性≤±1 nm;基于平凸柱面透镜的光学结构设计可将探测输出光强值提高15%以上,可有效提高光谱测量的灵敏度;同时,经过平凸透镜二次聚焦后的光斑尺寸更小,可选用感光面积小、截至频率大的单管探测器实现光谱探测,可降低系统成本、抑制外部光噪声,满足扫描频率较高的扫描光栅式光谱仪的光谱分辨率需求。因此,提出的基于MOEMS集成扫描光栅微镜和改进型非对称式C-T结构的近红外光谱仪满足高性能、微型化和低成本的光谱仪发展需求。

一种C-T结构改进型光谱仪的光路结构设计

针对光纤光谱仪传统的Czerny-Turner结构存在性能不稳定、调节效率低的问题,提出了用1面反射镜来同时充当准直镜和聚焦镜的新光路结构,并以200~1000 nm为工作波段、分辨率不低于1.5 nm为初始条件,结合零阶和一阶消像散条件及消彗差条件,推导出了对称交叉型C-T结构的一阶消散条件;随后使用Zemax对设计的光路结构进行了仿真分析和优化,并根据优化结果完成了相应的机械结构设计。对优化后的光路结构进行了稳定性、分辨率、波长工作范围测试,结果显示,实现了工作波段在200~1000 nm、分辨率1.5 nm、稳定性有所提高的设计要求。

The development,performances and applications of the monochromatic X-rays facilities in(0.218–301)keV at NIM,China

Space scientific exploration is rapidly becoming the primary battlefield for humankind to explore the universe.Countries worldwide have launched numerous space exploration satellites.Accurate calibration of the detectors on the ground is a crucial element for space science satellites to obtain observational results.For the purpose of providing calibration for various satellite-borne detectors,multiple monochromatic X-rays facilities have been built at the National Institute of Metrology,P.R.China(NIM).These facilities mainly pertain to grating diffraction and Bragg diffraction,and the energy range of the produced monochromatic X-rays is 0.218–301 ke V.These facilities have a high performance in terms of energy stability,monochromaticity,and flux stability.The monochromaticity was greater than 3.0%.The energy stability of the facility is 0.02%at 25 ke V over 8 h,and the flux stability was within 1.0%at 25 ke V over 8 h.Calibration experiments on the properties of satellite-borne detectors,such as energy linearity,energy resolution,detection efficiency,and temperature response,can be conducted at the facilities.Thus far,the calibration of two satellites has been completed by the authors,and the work on three other satellites is in progress.This study will contribute to the advancement of X-ray astronomy the development of Chinese space science.

C-T组合型锁扣钢管桩在深水围堰工程中的应用

随着国家对水利及海洋工程的投资建设力度不断加大,涉水工程越来越多,围堰作为涉水工程的重要围护结构,其应用越来越广泛。在深水工程围堰中,围堰封堵止水历来是围堰施工中的难点,也是决定后期围堰内能否安全施工的重要因素,本文以小清河复航工程引黄济青倒虹吸围堰为例,详细介绍C-T组合型锁扣钢管桩插打及封堵止水工艺,总结了C-T组合型锁扣钢管桩的施工控制要点及优缺点,以期给类似工程提供参考。

A tunable XUV monochromatic light source based on the time preserving grating selection of high-order harmonic generation

We accomplish a laboratory facility for producing a femtosecond XUV coherent monochromatic radiation with a broad tunable spectral range of 20 eV-75 eV. It is based on spectral selected single-order harmonics from intense laser driven high harmonic generation in gas phase. The time preserving for the selected harmonic radiation is achieved by a Czerny-Turner type monochromator designed with a conical diffraction grating mount for minimizing the time broadening caused by grating diffraction and keeping a relatively high diffraction efficiency. Our measurement shows that the photon flux of the 23-order harmonic（H23） centered at 35.7 eV is 1×10~9 photons/s approximately with a resolving power E/？E ≈ 36.This source provides an ultrashort tunable monochromatic XUV beam for ultrafast studies of electronic and structural dynamics in a large variety of matters.

C-T型锁扣钢管桩在嘉鱼长江大桥围堰施工中的应用

嘉鱼长江大桥北岸10号主墩承台位于长江岸边,承台采用矩形结构,几何尺寸为58.5m×29.5m×8m,承台施工工期较紧,通过方案比选,采用锁扣钢管桩围堰法进行施工,介绍工艺流程及施工要点,工程效果较好。

C-T型分光系统避免零级回反的设计计算方法

一些C-T型单色器存在光栅零级回反现象,这会引起严重的杂散光问题。从球面准直反射镜及光栅系统的基本几何关系入手,运用几何光学原理入手,分析了C-T型单色器光栅准直镜系统产生零级回反的充分必要条件,即零级光柱落在第一准直镜反射面,同时光栅一部分位置落入第一准直球面镜的边缘法线以内。从而提出了在初始设计计算阶段避免光栅准直镜系统产生回反的理论措施及设计计算方法。即在设计阶段适当增加入射角,以及适当增加光栅与第一准直镜的相对距离。从而使得光栅位置全部落在第一准直镜边缘法线以外,因此能够确保系统无零级回反产生。