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1.
平面光栅摄谱仪是地球化学普查样品中,测定银、硼、锡等元素常用的仪器.为提高分析效率和质量,2015年我单位将二米平面光栅摄谱仪改造为CCD-Ⅰ型平面光栅直读光谱仪.改造后的仪器检测限为Ag:0.013μg/g,Sn:0.43μg/g,B:0.71μg/g.精密度(RSD%,n=12)均小于10%,测定国家一级标准物质结果与标准值相符,完全满足地球化学普查样品中银、硼、锡等元素的分析要求.  相似文献   

2.
2017年三月我单位购进湖北地质中心实验室王鹤龄研发专利技术,将原来WP-1米平面光栅摄谱仪改造为CCD-1型平面光栅电弧直读发射光谱仪。CCD-1型平面光栅电弧直读发射光谱仪是对WP-1米平面光栅摄谱仪改造升级后,成为一款高性能全谱直读光谱仪。我们在原有CCD-1平面光栅电弧直读发射光谱仪测定硼锡银钼基础上,通过多次方法实验,研究出一次摄谱同时测定铅锡钼铜银锌六项元素的分析方法。六个元素测定的检出限Pb 1.56 Sn 0.42 Mo0.21 Cu 0.87Ag 0.012 Zn 7.95(RSD﹪ n=12)1.25﹪~7.43﹪,测定结果经验证准确度精密度检出限和合格率各项指标满足地质矿产实验室管理规范的要求。  相似文献   

3.
关于平面反射式闪耀光栅的问题讨论   总被引:1,自引:0,他引:1  
曾泳淮 《大学化学》1997,12(5):47-49
关于平面反射式闪耀光栅的问题讨论曾泳淮(北京师范大学化学系100875)平面反射式闪耀光栅是目前光学分析法中广泛使用的分光元件,无论在原子发射、原子吸收、紫外可见、荧光光谱和红外光谱仪中都用作分光元件。因此,在仪器分析教学中给学生介绍一点闪耀光栅的...  相似文献   

4.
黎拒难 《化学通报》1992,(12):45-47
光栅是各类光谱分析仪器的重要部件,光栅的分光原理特别是闪耀光栅的定向闪耀原理无疑是仪器分析课程的重要内容之一。但是,在仪器分析基础课教材中,怎样深入浅出、简单明瞭地表述这个问题,并对闪耀光栅的一些基本概念给出确切的定义,尚需进一步讨论。学生们在物理光学中已学习过光栅刻槽的反射面与光栅平面重合的理想光栅,对下面两  相似文献   

5.
固体内部压力是国防科技领域需重点监测的参数之一,目前使用较多的测压设备均存在电磁干扰严重、可靠性及准确性差等缺陷.针对以上不足,本研究设计了光纤光栅耐高压固体压力传感器.采用平面薄板作为弹性承压膜片,利用压力作用下的挠度,拉动压力敏感光栅产生轴向位移,实现压力传感.根据测压范围,对其结构进行理论计算,并进行有限元仿真,验证了本设计的可行性.在恒温条件下,进行了压力校准实验,并通过处于同一温度场的温补光栅进行温度补偿,修正应变光栅的温漂.实验结果表明,构建的承压光栅(FBG)压力传感器可以进行压力传感,测压上限可达50 MPa,线性度为99.2%.  相似文献   

6.
简要介绍了WPP2型平面光栅摄谱仪常见故障现象,对故障产生的原因进行了分析,归纳总结了故障排除的方法与过程.  相似文献   

7.
(通信处: 产品名称二米平面光栅摄谱仪 表1北京光学仪器厂部分产品介绍北京通县西门北京光学仪器厂经济部何存兴.电话9526901一355,电报82凡4)型号WSP一1主要用途用于钢铁、有色金属、地质矿产、环保、卫生等样品的定性、半定量和定量发射光谱分析高频等离子体平面光栅摄谱仪WP一ZL 主要技术指标焦距f=1800 mm光栅:1200条/mm一级色散率:4,5入/mm一级复盖波长:1080凡(2 40m州宽)主机指标同上ICP激发方式:自激式激发功率:3.5 kVA 参考价格阮)包括交直流电弧发生器28600元包括ICP光源和交直流电弧49100兀巧0平面光栅摄谱仪WP一075用于微…  相似文献   

8.
为了发挥小仪器的效能,我们试验了用0.5米平面光栅摄谱仪测定低含量锡。采用正交设计选择了主要摄谱条件。测定下限为0.003%。对锡含量为0.134%和0.011%的试样进行7次测定,相对标准偏差分别为7%和8%。用本法测定管理样以及与其它方法结果对照,结果基本吻合。一、仪器及工作条件WSP-2型0.5米平面光栅摄谱仪。三透镜  相似文献   

9.
提出了一种基于灰度投影与位平面匹配的图像全局运动估计算法,并将其应用于无人机图像稳定系统中.算法采用灰度投影获取全局运动,用网格检测和灰度切分图精确匹配的方法获取更准确的运动数据.由于算法中使用自适应性的灰度切分层选择和基于灰度投影的运动估计缩小搜索区域,使算法效率在空间复杂度和时间复杂度上得到提高,具有较好的实时性和对影像的适应性.  相似文献   

10.
本文介绍了多电子原子光谱的基本原理.并结合使用WSP-1型平面光栅摄谱仪拍摄钙原子光谱精细结构,通过朗德能级间隔规则及选择定则的分析,对其4d~3D→4p~3P~0及4p~23P→4p~3P~0谱线进行了认证.提供了多电子原子光谱谱线认证的一般方法.  相似文献   

11.
A comprehensive three-dimensional (3D) microanalysis procedure using a combined scanning electron microscope (SEM)/focused ion beam (FIB) system equipped with an energy-dispersive X-ray spectrometer (EDS) has been developed. The FIB system was used first to prepare a site-specific region for X-ray microanalysis followed by the acquisition of an electron-beam generated X-ray spectral image. A small section of material was then removed by the FIB, followed by the acquisition of another X-ray spectral image. This serial sectioning procedure was repeated 10-12 times to sample a volume of material. The series of two-spatial-dimension spectral images were then concatenated into a single data set consisting of a series of volume elements or voxels each with an entire X-ray spectrum. This four-dimensional (three real space and one spectral dimension) spectral image was then comprehensively analyzed with Sandia's automated X-ray spectral image analysis software. This technique was applied to a simple Cu-Ag eutectic and a more complicated localized corrosion study where the powerful site-specific comprehensive analysis capability of tomographic spectral imaging (TSI) combined with multivariate statistical analysis is demonstrated.  相似文献   

12.
Carbonic anhydrase (CA) IX is a very interesting subject for study due to its overexpression in cancer and its expression in very few normal tissues. There are not yet experimental 3D structures of the catalytic domain of this isozyme, and only a few computational studies have been reported. A homology model of CA IX was developed, and using Gold software 124 CA IX inhibitors were docked. The best poses of the ligands were then used as an alignment tool for the development of the first reported CA IX 3D-QSAR model. The obtained results confirm the reliability of the constructed CA IX model and the proposed computational strategy for investigating CAs.  相似文献   

13.
Density-based spatial clustering of applications with noise (DBSCAN) is an unsupervised classification algorithm which has been widely used in many areas with its simplicity and its ability to deal with hidden clusters of different sizes and shapes and with noise. However, the computational issue of the distance table and the non-stability in detecting the boundaries of adjacent clusters limit the application of the original algorithm to large datasets such as images. In this paper, the DBSCAN algorithm was revised and improved for image clustering and segmentation. The proposed clustering algorithm presents two major advantages over the original one. Firstly, the revised DBSCAN algorithm made it applicable for large 3D image dataset (often with millions of pixels) by using the coordinate system of the image data. Secondly, the revised algorithm solved the non-stability issue of boundary detection in the original DBSCAN. For broader applications, the image dataset can be ordinary 3D images or in general, it can also be a classification result of other type of image data e.g. a multivariate image.  相似文献   

14.
Scanning electron microscopy (SEM) is widely used in the science of materials and different parameters were developed to characterize the surface roughness. In a previous work, we studied the surface topography with fractal dimension at low scale and two parameters at high scale by using the variogram, that is, variance vs. step log-log graph, of a SEM image. Those studies were carried out with the FERImage program, previously developed by us. To verify the previously accepted hypothesis by working with only an image, it is indispensable to have reliable three-dimensional (3D) surface data. In this work, a new program (EZEImage) to characterize 3D surface topography in SEM has been developed. It uses fast cross correlation and dynamic programming to obtain reliable dense height maps in a few seconds which can be displayed as an image where each gray level represents a height value. This image can be used for the FERImage program or any other software to obtain surface topography characteristics. EZEImage also generates anaglyph images as well as characterizes 3D surface topography by means of a parameter set to describe amplitude properties and three functional indices for characterizing bearing and fluid properties.  相似文献   

15.
Automatic registration for images of two-dimensional protein gels.   总被引:5,自引:0,他引:5  
Z Smilansky 《Electrophoresis》2001,22(9):1616-1626
Two-dimensional polyacrylamide gel electrophoresis 1 (2-D PAGE 1) is currently the method of choice for separating complex mixtures of cellular proteins. Despite its usefulness, 2-D PAGE is not being applied to its full potential because of difficulties with both the method and analysis of the results. One of the key problems is the difficulty and slowness of image analysis, especially registration (image alignment), which is laborious and the results unsatisfactory. We have developed a novel system for analysis of 2-D PAGE images, called Z3, that performs the analysis faster and more precisely. The Z3 system employs novel approaches to image registration, image display, computation of differential expression, and the design and analysis of 2-D gel experiments. This paper describes in detail the registration algorithm, and briefly discusses the merits of complementary pseudocolor display. The registration algorithm is novel in that for the first time raw-image-based registration technology is applied to 2-D gel analysis.  相似文献   

16.
Microsomal prostaglandin E synthase-1 (mPGES-1) is a promising target for development of next-generation anti-inflammatory drugs. It is crucial for rational design of the next-generation anti-inflammatory drugs to know the three-dimensional (3D) structure of mPGES-1 trimer and to understand how mPGES-1 binds with substrates and inhibitors. In the current work, a 3D structural model of human mPGES-1 trimer has been developed, for the first time, by performing combined homology modeling, molecular docking, and molecular dynamics simulation. The 3D structural model enables us to understand how mPGES-1 binds with its substrates/inhibitors, and the key amino acid residues for the mPGES-1 binding with ligands have been identified. The detailed 3D structures and calculated binding free energies for mPGES-1's binding with substrates and inhibitors are all consistent with available experimental data, suggesting that the 3D model of the mPGES-1 trimer and the enzyme-ligand binding modes are reasonable. The new structural insights obtained from this study should be valuable for rational design of next-generation anti-inflammatory drugs.  相似文献   

17.
We performed X-ray fluorescence holography measurements on an In-doped Bi2Se3 topological insulator and obtained an in-plane atomic image in the vicinity of In. We found that atomic images at the positions of the first nearest neighbors (NNs) are very weak whereas those at the positions of the second and the third NNs are relatively strong. On the basis of the fact that In is half of the atomic number of Bi, we attributed the origin of this feature to the clustering of the In atoms in the Bi plane. We calculated the intensity of the atomic images and confirmed that the formation of In cluster results in a decrease by 30% in the first NN atomic image intensity. However, the decrease in the magnitude is not enough to explain the experimental results, suggesting another contribution such as the lattice distortions. The effect of the lattice distortion on the atomic image intensity is discussed on the basis of the simulation including the positional fluctuation of In atoms.  相似文献   

18.
非相干数字全息术是当前国际前沿重要研究领域之一。传统全息术由于采用相干光源照明会在全息图记录过程中引入大量散斑噪声和寄生干涉,且对设备和记录条件要求很高,极大地限制了其应用范围。采用非相干光源照明的非相干全息术则可完全避免这些问题。菲涅耳非相干相关全息术是非相干全息术中最重要的类型之一。本文简要说明了菲涅耳非相干全息术的原理与特点,重点分析了该技术在抑制直流项和共轭像干扰、提高成像分辨率、改善再现像质量及相关应用等方面的研究进展。  相似文献   

19.
数字全息技术由于其高灵敏度、高准确度、分辨能力强,且再现、存储及传输方便灵活等特点,在微纳结构与生物细胞的测量领域中得到越来越广泛的应用。然而,记录数字全息图受孔径有限等因素的影响,其重构图像会产生一些类似于波纹的边缘误差,导致成像质量降低和CCD视场不能充分利用。本文首先基于数字全息理论对误差产生原因进行了理论分析,并对边缘误差产生影响的数值参数进行了详细讨论,在此基础上,提出了一种周期延拓迭代方法对全息图进行预处理,并使用图像均方差值对迭代结果进行评价。通过计算机仿真与实验,结果表明,该方法能够显著降低边缘误差,提高再现图像质量。  相似文献   

20.
In recent years, the 3D X-ray microcomputed tomography (3DμCT) has become a useful method to access the internal geometry based microarchitecture of bones. All measurements are based on the image quality. In this context, the aim of this work is to investigate bone quality in terms of strength parameters determined by 3DμCT. The system that was used to do the 3DμCT was a microfocus Fein Focus which has a microfocus X-ray tube, adjustment of the magnification factor of the captured image by mobile supports and an image intensifier with a diameter of 9 in. The results show that microtomography by microfocus X-ray tube is a powerful technique that can be used to analyze bone microstructures. A quantification procedure conducted with a locally developed program, produced images with 20 μm of resolution for different bone samples.  相似文献   

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