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1.
本文研究了感耦等离子体原子发射光谱(ECP-AES)法直接测定土、沉积物中常、微量元素的光谱干扰,以及用多元光谱拟合(MSF)校正的方法。讨论了积分时间及谱线漂移对MSF法的影响。比较了离峰扣背景法与MSF法的效果,对水系沉积物GBW07306测定结果表明,MSF法得出的结果更接近推荐值,且其检出限及相对标准偏差比离峰扣背景法分别改善了1.3~9.0倍和1.1~4.9倍。  相似文献   

2.
本文研究了柱芯电极测定西藏斑岩铜矿中8个主次要元素,并与用其他电极测定的结果进行了对比实验。本文还讨论了组分影响及消除方法。对铜矿区样品测定,其RSD(n=15)为Cu±3.3%,Mo±4.1%,Ag±3.7%,Pb±6.5%。Zn±6.5%,As±7.3%,W±6.9%以及Bi±6.9%。用化学分析,外检和标样验证了方法的可靠性。  相似文献   

3.
ICP—AES法测定复合肥中磷,钾,锌,锰和硼   总被引:6,自引:1,他引:5  
用ICP-AES法同时测定了复合肥中磷,钾锌锰和硼,确定了仪器的工作参数,对分析线的选择,背景扣除。酸度影响和共存元素间的干扰等进行了研究。方法的回收率为95%-104%,相对标准偏差为2.66%-5.54%。  相似文献   

4.
罗马 《中国物理 C》1984,8(5):539-547
我们在γ-p质心系里用微扰QCD方法计算了γ+p→2γ(大PT)反应的双微分截面d2σ/dxTdxL, 并分析了它的两种可能的背景(γ+p→γ+q(q)和γ+p→γ+q(q)). 文中指出, 利用该反应所具备的大pT光生和直接光子对出射过程的双重特点, 可以把这两种背景大大压低. 计算结果表明, 用QCD预言的γ+p→2γ(大PT)反应不但具有本底干净的显著特点, 而且在相当大的(xT, xL)范围内, 计算得到的反应截面可以在目前的实验精度下测量. 因而, 在实验上精确测定此过程, 对于检验QCD上有意义的.  相似文献   

5.
铬渣中铬,镍,锌,锰和铁的X射线荧光法测定   总被引:1,自引:0,他引:1  
本文首次研究了用X射线荧光光谱法测定铬渣中Cr、Zn、Ni、Mn和Fe元素的模拟标样,样品直接压片不经化学处理。用稀释样品校正试样的基体效应。用人工模拟标样所建立的元素浓度与X射线强度间的线性函数关系令人满意,所试元素的线性相关系数均在0.99以上,测定结果与化学法基本一致。Cr的检测下限为0.036%;Fe为0.039%;Ni为35.33μg/g;Mn为498.18μg/g;Zn为55.61μg/g。各元素的相对标准偏差均低于2.48%。并首次用非线性方法研究了铬渣样品稀释比中Cr、Ni、Zn、Mn、Fe与X射线强度的线性关系。  相似文献   

6.
锰结核中硅,铝,铁,镁,磷,钾,锰,钛的XRFA   总被引:1,自引:0,他引:1  
本文叙述了用XRF分析锰结核中Si、Al、Fe、Mg、P、K、Mn和Ti的方法。按照通常锰结核的主次成分制备6个人工合成标准,根据Sherman方程计算了已知成分(二元系统)的相对强度。用L-T方求得了互致元素校正的理论α系数(基本的、混合的、修正的),用DATAFLEX151B计算机以BASIC语言汇了“PRA,APU”计算机程序。然后进行非线性回归分析了锰结核样品得到了满意的结果。  相似文献   

7.
本文研究了用10%N_(7402)-MIBK萃取预富集,以XRFS测定岩石、土壤中Pb、Zn、Cu、Cd、Mo、Bi、Sn等痕量元素的方法,并研究了背景对检出限的影响,选Sm作内标。确定了样品分解,薄样制备方法和测定条件,检出限较直接粉末压片法约降低两个数量级,精密度通常优于4%,本法分析结果与标样推荐值吻合。  相似文献   

8.
本文对于原子核乳胶核—2、核—3制备方法中的几个主要问题进行了初步研究。通过这些研究,我们掌握了制备过程中各种主要因素的关系和它们对于乳胶性能的影响,从而制成了性能良好的原子核乳胶。我们用控制乳化过程中溴离子浓度的方法解决了颗粒大小均匀问题;选择适当的成熟条件和用三乙醇胺增感解决了乳胶对质子的灵敏度问题;用加金盐的方法解决了潜影衰退问题;用纯化明胶的方法解决了雾点问题。  相似文献   

9.
火焰原子吸收法测定钢铁中钴时的背景吸收及消除   总被引:7,自引:0,他引:7  
对于背景校正装置的原子吸收分光光度计,用火焰原子吸收法测定钴时,由于铁等有背景吸收(指铁的背景通过吸收池以后的背景,称为背景吸收),故无法用标准加入法测定钢铁中低含量钴。本文对测钴时的背景吸收及铁的干扰做了详细的研究,用金242.8nm谱线做为测钴时背景吸收校正线,可完全扣除背景吸收。用标准加入法测定了钢及高温合金中低含量钴。  相似文献   

10.
多特征融合匹配的多目标跟踪   总被引:3,自引:0,他引:3  
闫辉  许廷发  吴青青  徐磊  吴威 《中国光学》2013,6(2):163-170
针对复杂背景的视频图像多目标跟踪遮挡问题,提出了一种多特征融合匹配的多目标跟踪方法。基于自适应高斯混合背景模型重构和更新背景策略,实现当前帧背景减除和多目标检测;采用目标的颜色特征、质心位置、运动速度等特征进行融合匹配跟踪;最后,通过区域辅助判定策略将场景下的目标状态分为目标进入场景、目标退出场景、目标暂消、目标重现、目标融合和分裂5种状态,用质心预测方法和遮挡因子辅助匹配来提高匹配正确率。仿真实验结果表明:采用该方法跟踪同一目标和不同目标的相似度平均值分别为0.949 71和0.505 73,优于单一颜色特征信息匹配;目标遮挡结束后重新匹配相似度为0.972 83,实现了复杂背景下具有表面相似性的多目标实时跟踪。  相似文献   

11.
氢化物发生原子荧光光谱法测定钢铁及合金材料中痕量铋   总被引:3,自引:0,他引:3  
采用氢化物发生原子荧光光谱法 ,研究了用硫代氨基脲—抗坏血酸及磷酸作干扰抑制剂消除大量基体元素干扰 ,提出了钢铁及合金材料中痕量铋的分析方法。方法的检出限为Bi=0 0 2 μg·g-1( 3δ ,n =11,0 2 0 0 0 g试样 )。用该方法分析了中低合金钢 ,铁镍基、镍基、钴基高温合金 ,铜合金等样品 ,获得了满意的结果。  相似文献   

12.
This paper reports on the results of the analysis of the mesostructure of phase precipitates formed in the steel P91 during heat treatment in the temperature range of 600–820°C after quenching at 1050°C for 30 min. Measurements have been performed by the small-angle polarized neutron scattering (SAPNS) method with the separation of nuclear-magnetic interference scattering. The characteristic sizes of the phases precipitated during heat treatment have been determined to be in the range of 150–450 Å. It has been demonstrated that the method is highly effective for solving problems of this class, which is based on the possibility to separate and investigate nuclear-magnetic contrast scattering against the background of the total nuclear and magnetic small-angle scattering.  相似文献   

13.
本文提供了一种测定金属硅中B,Fe,Al,Ca,Mn等14个杂质元素的ICP-AES方法,在样品处理过程中,加入适量体积的甘露醇能够抑制B的挥发。用本方法测定了一个国家地球化学标准样(GSR-4),结果令人满意。  相似文献   

14.
The adhesion of steel cord to rubber is very important for the quality of reinforced rubber products, e.g. tyres. Therefore, steel cord is often plated with brass, which will lead to CuxS bonds after reaction with sulfur compounds in the rubber. A unique in‐situ analytical method has been developed to investigate the sulfur–brass interface: the sulfuring process has been simulated via a heating process in a water‐free transparent ionic liquid with added sulfur and the reaction at the brass‐coated steel cord has been monitored in real time with Raman spectroscopy. The grown CuxS film seems to be similar to the layers at the steel cord interface in real rubber materials. The model system can also be used to perform electrochemical measurements at the same time. The thickness of the CuxS layer has been estimated from the measured current during a cathodic stripping process. Copyright © 2013 John Wiley & Sons, Ltd.  相似文献   

15.
人工神经网络直读光谱法测定钢中酸溶铝   总被引:1,自引:0,他引:1  
用火花直读光谱法测定钢中不同状态的铝是目前研究的热点之一。本文确立了直读光谱法的分析条件,将人工神经网络用于直读光谱法,用直读光谱的全铝光谱强度值作为网络的输入,标样中的酸溶铝值作为期望值,建立神经网络模型,用神经网络直读光谱法测定中低合金钢中酸溶铝含量,分析结果的准确度与化学分析法基本一致。神经网络使用改进的BP算法,避免了学习过程可能产生的麻痹现象,提出了目标向量的简单变换方法。该法用于钢中酸溶铝的直接测定,获得满意结果。  相似文献   

16.
背景扣除和强度校正对激光诱导等离子体光谱参数的影响   总被引:1,自引:0,他引:1  
激光诱导击穿光谱技术以其无需样品预处理、分析速度快、能实现多元素同时检测和远程分析等优点已经被广泛应用于诸多领域的物质成分定性或定量分析。该技术的理论基础是激光诱导等离子体。对等离子体光谱参数(如光谱谱线强度、等离子体温度等)的准确测量是利用该技术进行定性或定量分析的前提条件。实际的实验系统中,由于仪器本身固有的性能限制,会造成采集光谱信号的失真,从而限制等离子体光谱参数的精确测量或计算。为了克服仪器固有性能的影响,分析了实验系统所用中阶梯光栅光谱仪和传输光纤的固有性能缺点对光谱信号背景噪声和元素谱线绝对强度的影响,然后采用剥峰法对光谱信号中存在的锯齿状背景噪声进行扣除,利用辐射定标光源的标准光谱数据对谱线绝对强度进行校正,并对比了背景扣除和强度校正对等离子体谱线强度和等离子体温度的影响,实验表明谱线强度校正对合金钢等离子体380 nm以下的光谱信号具有较大影响,通过背景扣除和强度校正后,等离子体温度由13 401.75 K降低至8 980.72 K,玻尔兹曼平面法求解等离子体温度的拟合决定系数由0.60提高至0.91。因此在光谱数据处理之前对测量光谱进行背景扣除和强度校正是十分必要的,为提供可靠地光谱数据进行物质成分定性或定量分析奠定了基础。  相似文献   

17.
中低合金钢中不同形态铝硼的直读光谱分析法   总被引:3,自引:1,他引:2  
马键 《光谱实验室》1998,15(4):60-63
在直读发射光谱仪上用峰值积分法(PIM)对中低合金钢中不同形态(固溶态和夹杂态)铝和硼的成分进行了测定,方法的精密度和准确度均能满足一般生产的要求。  相似文献   

18.
Raman spectroscopy has attracted interest as a non‐invasive optical technique to study the composition and structure of a wide range of materials at the microscopic level. The intrinsic fluorescence background can be orders of magnitude stronger than the Raman scattering, and so, background removal is one of the foremost challenges for quantitative analysis of Raman spectra in many samples. A range of methods anchored in instrumental and computational programming approaches have been proposed for removing fluorescence background signals. An enhanced adaptive weighting scheme for automated fluorescence removal is reported, applicable to both polynomial fitting and penalized least squares approaches. Analysis of the background fitting results for ensembles of simulated spectra suggests that the method is robust and reliable and can significantly improve the background fit over the range of signal, shot noise and background parameters tested, while reducing the subjective nature of the process. The method was also illustrated by application to experimental data generated from aqueous solutions of bulk protein fibrinogen mixed with dextran. Copyright © 2013 John Wiley & Sons, Ltd.  相似文献   

19.
Schaaf  Peter  Landry  Felix  Han  Meng  Carpene  Ettore  Lieb  Klaus-Peter 《Hyperfine Interactions》2002,139(1-4):307-314
Nitriding is a common method for improving the hardness, mechanical properties, wear and corrosion resistance of metals. Laser nitriding of metals is an efficient process, where the irradiation of surfaces in air or nitrogen atmospheres with short laser pulses leads to a fast take-up of nitrogen into the irradiated surfaces. This process has been extensively investigated for pure iron, but usually, no tools or functional parts are made of pure iron. Mainly steel or cast iron is used as a base material. Therefore, when looking for technical applicability, also the influence of alloying elements on the laser nitriding process is of great interest. Besides the pure iron various carbon steels and an austenitic stainless steel were studied in laser nitriding experiments in order to investigate the influence of the material itself. Here, the process is investigated via Conversion Electron and X-ray Mössbauer Spectroscopy (CEMS and CXMS), Resonant Nuclear Reaction Analysis (RNRA), and X-Ray Diffraction (XRD). It appears that carbon steels are even better suited for the laser nitriding process than pure iron, and the laser nitriding also works efficiently for the stainless steel which is normally difficult to be nitrided.  相似文献   

20.
This paper discusses a new method of background estimation in the energy‐dispersive X‐ray fluorescence (EDXRF) analysis, which is based on Fourier Transform (in this paper, we call it Fourier Transform background estimation method). Compared with the Sensitive Nonlinear Iterative Peak method, the new method has the feature of FWHM independence. It has been proved that a background can be estimated automatically and accurately by the new method in the synthesized spectrum and the spectra from measurement. Fourier Transform background estimation method can estimate the background accurately in the EDXRF spectrum using an X‐ray tube source. Copyright © 2011 John Wiley & Sons, Ltd.  相似文献   

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