阶梯光栅光谱仪

德国柏林激光器技术公司生产一种阶梯光栅光谱仪，该光谱仪通过激光诱导等离子体光谱学同时分析元素。仪器在175nm-750nm的波长范围内探测元素，在真空紫外中的光谱分辨力为35000，在紫外一近红外范围内的光谱分辨力为15000。两台对称排列的摄谱仪的光谱照射一个共用探测器。     

分波段式中阶梯光栅原子发射光谱仪

受探测器发展水平的限制,以中阶梯光栅光谱仪为分光模块的ICP-AES电感耦合等离子体原子发射光谱仪（ICP-AES）难以实现宽波段内多元素的同时测量。本文对现有中阶梯光栅光谱仪进行了改进,设计出一种适用于ICP-AES多元素同时测量的分波段式中阶梯光栅光谱仪。通过改变棱镜的入射角度,将系统波长扩展为200~900 nm,光谱分辨率为25 000,突破了现有探测器尺寸的限制,实现了宽波段范围内的多元素快速测量。将中阶梯光栅光谱仪与固态ICP光源组合,进行了系统波长标定与化学试样测试。实验结果表明：波长测试误差小于0.01 nm,满足化学元素精确判读要求;分波段式中阶梯光栅光谱仪在保持原有仪器性能的前提下,增宽了仪器的有效光谱探测范围,为多元素的同时测量提供了有效手段。     

激光诱导等离子体光谱直接探测气溶胶中的锶元素

气溶胶中锶元素的监测对于大气污染防治和工业设施排放监控具有重要意义。激光诱导等离子体光谱技术具有无需采样预处理、可原位快速检测等优势，在环境介质成分直接在线监测方面具有极大的应用潜力。介绍了基于实验室搭建的LIPS装置开展的气溶胶中锶元素的直接探测工作。利用整体平均法对气溶胶等离子体进行光谱分析，结果显示实验装置对锶元素的检测限为809μg/m3。对于低密度气溶胶光谱，条件分析法可以将平均光谱的信噪比提升8倍。基于实验结果讨论了含锶气溶胶统计学特性和数据分析方法的影响。气溶胶中颗粒物的密度对等离子体温度的影响极小，光谱强度变化直接反应了激光激发气溶胶颗粒物的数量。通过对条件分析法使用范围的讨论，提出在测量周期内利用累计光谱取代平均光谱，可将系统的灵敏度提升近3个数量级。实验装置的检测限达到1.3μg/m3，初步满足工业排放监测的需求。     

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。     

小型高精度软X射线-极紫外反射率计

针对探月二期工程中的有效载荷之一极紫外相机中的多层膜光学元件反射率测量的需要,搭建了一台使用液体靶激光等离子体光源的小型软X射线一极紫外波段反射率计。该反射率计主要由激光等离子体光源、Mcpherson247动狭缝掠入射单色仪及相关的数据采集系统组成。单色仪工作波段为1～125nm,光谱分辨率〈0．08nm。无碎屑的液体靶激光等离子体光源的使用避免了光学元件的损坏,而动狭缝掠入射单色仪的使用则提高了光谱分辨率和波段范围。使用该反射率计实测了工作波长为13．5nm和30．4nm的Mo／Si多层膜的反射率,测量结果表明测量重复性优于±0．5％,实现了对多层膜反射率的高精度测量。     

水靶激光等离子体光源11~20 nm波段光谱实验

实验以水为靶材,Nd:YAG激光器为照射激光构成激光等离子体光源,产生软X射线-极紫外辐射。利用McPHERSON 247型掠入射软X射线-真空紫外单色仪、AXUV100硅光电二极管,测量了11~20 nm波段水靶激光等离子体光源的光谱。实验表明,在11~20 nm波段水靶激光等离子体光源存在多条线谱,均由水中氧离子电子跃迁产生。所用单色仪光谱分辨率Δλ≤0.075 nm,波长扫描间隔0.5 nm。另外,采用在喷嘴处加热的办法,很好地解决了水进入真空系统后绝热膨胀与蒸发过程中温度骤降而结冰的问题,有效地抑制了喷射距离缩短,克服了等离子体对喷嘴腐蚀严重的问题。     

碳室约束对激光等离子体辐射的增强效应

以土壤样品为靶,提出利用小型碳室对高能量激光诱导等离子体进行空间限制来提高等离子体发射光谱质量.采用高能量脉冲激光烧蚀土壤样品,利用组合式多功能光栅光谱仪和CCD探测器等组成的光谱分析系统记录光谱信息,研究了激光诱导等离子体在有或无碳室约束条件下辐射强度的变化;通过光谱学测量方法求得电子温度和电子密度,用以解释等离子体辐射增强的机理.实验结果显示,当利用小型碳室约束激光等离子体时,土壤样品元素Mn,K,Fe和Ti的光谱线强度比无碳室约束时分别提高了90.77％,101.71％,104.27％和60.77％;光谱信噪比分别提高了54.29％,55.30％,59.37％和38.80％;等离子体的电子温度和电子密度分别提高了1684 K和1.8×1016 cm-3.得到的结果表明,利用空间约束方法能够有效地提高激光诱导等离子体的发射光谱强度和信噪比,为利用激光诱导击穿光谱技术检测物质中低含量成分奠定了基础.     

小型的高精度软X射线-极紫外反射率计

针对探月二期工程中的有效载荷之一极紫外相机中的多层膜光学元件高精度反射率测量的需要,建立了一台使用液体靶激光等离子体光源的小型软X射线-极紫外波段反射率计。该反射率计主要由激光等离子体光源、Mcpherson 247动狭缝掠入射单色仪及相关的数据采集系统组成。单色仪波段范围1-125nm,光谱分辨率小于0.08nm。无碎屑的液体靶激光等离子体光源的使用避免了光学元件的损坏,而动狭缝掠入射单色仪的使用则提高了光谱分辨率和波段范围。使用该反射率计实测了工作波长为13.5nm和30.4nm的Mo/Si多层膜的反射率,测量结果表明测量重复性优于±0.5%。     

飞秒细丝-纳秒激光诱导击穿光谱技术对土壤重金属Pb元素检测

采用飞秒激光成丝-纳秒脉冲激光诱导击穿光谱技术(Filament-ns DP-LIBS)对土壤中重金属铅元素进行了定量分析。利用飞秒激光等离子体丝烧蚀含铅土壤样品,向外喷射低密度的土壤粒子源,经脉冲间隔Δt后,纳秒脉冲激光再烧蚀低密度土壤粒子,实现等离子体发射光谱强度增强,谱线宽度压缩,降低土壤中重金属铅元素的最小检测限。实验结果表明,相比飞秒激光等离子体丝诱导击穿光谱技术(FIBS),在飞秒-纳秒脉冲间隔Δt=10μs条件时,PbI405.78nm光谱增强因子为9.66,谱线宽度从3.66×10~(-10)m压缩至2.74×10~(-10)m,提高了LIBS光谱分辨率。FIBS和Filament-ns DP-LIBS条件下定标曲线的线性相关系数R~2分别为0.982和0.994。FIBS条件下的RSD和LOD值分别为7.37%和65.86mg/kg,Filament-ns DP-LIBS条件下的RSD和LOD值分别为3.27%和24.39mg/kg。研究结果表明,Filamentns DP-LIBS技术可以降低土壤重金属的最小检测限,提高LIBS的检测灵敏度。     

世界首台在线检测设备工程样机研制成功

正日前,在国家重大科学仪器设备开发专项的支持下,中科院光电研究院基于激光诱导光谱检测技术,研制出世界首台用于真空合金冶炼的在线检测设备工程样机。实时诊断与分析是影响冶金水平和合金成分精确控制的主要因素。目前国内外的钢铁冶炼主要是采用炉前离线分析,这制约了冶金生产技术水平的进一步提高。激光诱导光谱检测技     

在线质谱仪与在线气相色谱仪的比较及应用

本文介绍了在线质谱仪和在线气相色谱仪的原理及结构,并根据各自的特点对其应用进行简单总结和比较。由于两者工作原理的差异,在线质谱仪具有更快的分析速度和定性能力,而在线气相色谱仪对成分复杂的气体可达到更好的分离效果,在日常维护中,两者也存在较大的差别。因此,在实际应用中,要考虑现场监测的需要来选择合适的仪器。     

分光测色仪中的光谱仪系统

根据分光测色仪的应用需要,对分光系统、光电接收系统及相关电路组成的光谱仪进行了模块化设计,以方便仪器的整体设计、装调和测试。考虑分光测色仪是非成像光学仪器,故提出用光纤来连接各光学模块。根据应用需求提出了光谱仪的主要技术指标,所设计光谱仪很好地完成了球差和彗差的校正。分析了用滤光片消除二级衍射光谱的方法,解决了光纤和光谱仪数值孔径不匹配的问题。研制了光谱仪系统,其外形尺寸为130mm×90mm×45mm。实验测试显示,在狭缝宽度为50μm时,光谱仪各波段的光谱分辨率都可以达到2nm。对光谱仪进行了波长定标,定标精度小于0.2nm,整个工作波段占401个像元,满足1nm的波长输出间隔的设计要求。该光谱仪的可弯曲光纤和电子线路便于整机灵活布局与模块拆卸,同时方便单独测试。所述方法为分光测色仪的整机研制与测试打下了良好的基础。     

小型高性能质子转移反应飞行时间质谱仪的研制及其在呼吸气成分分析中的应用

研制可快速、在线分析挥发性有机物(volatile organic compounds,VOCs)的质谱仪器是现代气态有机质谱的重要发展方向.本研究自行研制了小型高性能质子转移反应飞行时间质谱仪(proton transfer reaction time of flight mass spectrometry,PTR-...     

Interstellar dust laser explorer: a new instrument for elemental and isotopic analysis and imaging of interstellar and interplanetary dust

We present the performance characteristics of a time-of-flight secondary ion mass spectrometer designed for 157 nm laser postionization of sputtered neutrals for high sensitivity elemental and isotopic analyses. The instrument was built with the aim of analyzing rare element abundances in micron to submicron samples such as interstellar grains and cometary dust. Relative sensitivity factors have been determined for secondary ion mass spectrometry which show an exponential dependency against the first ionization potential. This allows elemental abundances to be measured with errors below 25% for most major elements. The accuracy for isotope ratios, where isotopes can be resolved from isobaric interferences, is usually limited only by counting statistics. In laser secondary neutral mass spectrometry, the spatial and temporal overlaps between the laser and sputtered neutral atoms are modeled and predictions of total detection efficiency and isotopic and elemental fractionation are compared with experimental data. Relative sensitivity factors for laser-ionized secondary neutrals from a stainless steel standard are found to vary less than 3% above saturation laser pulse energy enabling more accurate quantification.     

一种在线监测快速过程质谱仪的设计与测试

工业生产过程中,如何实现准确、连续、可靠地检测目标组分是产物及排放物在线监测的重点。本工作研制了一种在线监测快速过程质谱仪,采用高增益的复合跨导线性放大技术代替传统的过程质谱仪所采用的对数放大技术,该技术可实现质谱仪在高增益条件下仍然具有超高速的特点,结合16位高速AD转换器,可以实现更快的扫描速度和更高的数据输出频率,能够更准确地捕捉快速反应（如热解）过程的气体生成物随时间的变化信息,进而实现反应特性的精准分析和量化,为反应动力学研究提供无失真的在线分析数据。本实验对该仪器的质量分辨率、灵敏度、质量轴稳定性、长时稳定性等关键技术指标进行了测试,同时结合煤热解反应过程监控需求进行了实际应用测试。结果表明,该仪器各项指标已基本达到市场主流过程质谱仪器的水平。     

Powder size measurement by acoustic emission

Acoustic emission was used to measure particle size properties of steel, cast iron, and alumina powders. Many powder samples with different weight and size distribution were prepared by sieving and their size distribution was measured by means of optical techniques. Acoustic emission measurements were carried out by dropping the powder on a metal plate to which an acoustic emission transducer was fixed, and results were expressed in terms of number of counts of four channels for data acquisition. The measurement set-up and procedure were original and never investigated before. Very good results were obtained for steel and cast iron samples, as measurement curves showed a clear linear trend as a function of the particle mean diameter and were vertically shifted in dependence of the sample weight. Alumina powders showed similar trends only for large particles and high weight differences.     

A real-time microcomputer-assisted array spectroradiometer for measurement and photobiological weighting of irradiance

We have modified a real-time array spectrometer to a spectroradiometer that allows on-line measurement of threshold exposure times for the UV-erythema and direct pigmentation, as well as of colour, by only one portable instrument. The spectral procedure used involves three stages of measuring and data processing; the rapid pick-up of the spectral power distribution of the incident radiation within the range from 200 to 800 nm, with a spectral resolution of 1.5 nm and shortest measuring time of 1.5 ms; the absolute detection of irradiance of an integral part of the spectrum by three GaAsP photodiodes near the entrance slit, with arched Teflon diffusers in front of it; and the photobiological weighting of measured spectral irradiances by the built-in microcomputer.     

Glove Box Adaptation of a High-Resolution Inductively Coupled Plasma Optical Emission Spectrometer for Analysis of Radioactive Materials

A glove box adaptation of a high resolution atomic emission spectrometer (AES) is reported employing sequential radial viewing of an inductively coupled plasma (ICP) source for determination of trace metallic elements in plutonium bearing samples. The original compact ICP-AES unit was converted into separate units. All electronic and optical components were placed outside radioactive containment. The entire assembly of the ICP torch, radiofrequency coil, nebulizer, spray chamber, peristaltic pump, and drainage system were placed inside the glove box for the analysis of radioactive samples. All these modifications were achieved without any compromise on the analytical performance of the spectrometer. Operational experience of the instrument for analysis as well as additional information for the upkeep and maintenance of the same is described. Proper optical alignment of the ICP source and detection system was performed.     

包覆对称组坯热轧制备高铬铸铁/低碳钢耐磨复合板

通过对碳钢板和高铬铸铁板进行六层对称包覆组坯,在1 200 ℃下分别采用30%和60%压下率多道次热轧制备了耐磨复合板。使用扫描电镜对试样的微观组织和界面结合情况进行了观察。试验结果表明：热轧后板形表现平直无翘曲现象;热轧过程中较软碳钢层的协调变形和应力释放作用使得高铬铸铁热变形裂纹敏感度降低,脆性高铬铸铁层实现了一定程度的热变形;两种材质界面结合质量良好,无可辨别的沿界面的夹层和空隙等缺陷;通过EDS能谱检测发现在高铬铸铁侧有无碳化物的过渡区,界面两侧的硬度值连续变化,证明两种材料实现了冶金结合。     

Compact instrumentation and (analytical) performance evaluation for laser-induced breakdown spectroscopy

In this work, a compact laser induced breakdown spectroscopy (LIBS) instrument was developed based on a high energy lightweight laser source and an integrated control system, making the instrument well integrated and convenient to use. The instrument has a compact size of 45?cm ×36?cm ×45?cm and weights only 21?kg. The spectrometer operated in the range from 180 to 850?nm with a resolution of 0.15?nm, which was customizable. The client software was customized as the interface for process control and data acquisition. Some procedures were carried out to evaluate the performance of this instrument. First, the laser source worked at an average energy value of 116?mJ, with a relative standard deviation of 2.58% for 9999 laser pulses after continuously running for 3?hr. Second, qualitative analysis was performed to show the classification ability for copper mineral samples. Besides, the calibration curves were achieved by using the emission lines of Cu (I) 510.55?nm, Cu (I) 521.82?nm, Zn (I) 307.58?nm, and Zn (I) 328.23?nm, with the correlation coefficient R² of 0.97432, 0.9826, 0.97286, and 0.98176, and the limit of detection was shown to be 0.0365%, 0.0399%, 39.581?µg·g^?1, and 47.081?µg·g^?1, respectively. According to the evaluation results, the compact laser source was excellent for stable measurement and the proposed compact instrument performed well for the qualitative and quantitative elemental analysis with satisfied results. Therefore, the proposed LIBS instrument has potential to find applications in a variety of circumstances.