背景FP法的应用--树脂薄膜的膜厚定量

散射X射线的理论强度计算法,即背景FP法,作为一种可定量测定树脂薄膜膜厚的新的分析方法之一受到注视。背景FP法是根据新的想法,在以往使用的FP法上添加计算散射X射线的理论强度而发展起来的。背景FP法作为本公司独自开发的数据处理方法之一,配备于岛津XRF-1700型顺序扫描X荧光光谱仪上,并应用于多种样品的定量分析。下面介绍有关背景FP法的想法及其应用例子。■何谓FP法所谓FP法是基本参数法的简称,是根据X射线发射理论,理论计算X射线强度的方法。这个强度叫做理论强度,通过与测定的强度即测定强度比较,可以定量分析样品的膜厚和…     

超细粉末粒度分布的X光小角散射分析

相应于超细多分散系的X光小角度散射强度,提出了精确而简便的解析方法——分割分布函数法。该方法把积分方程转化为线性方程组,通过求解相继给出粒度直方图,百分组成、平均粒度、比表面和分布宽度等特征参数。借助于YHP-97小型计算器,只需数分钟即可解印出全部结果。解算所要求的特定角度下的散射强度,也由相应的自动化测量给出。     

同位素X萤光载流分析富稀土矿浆浓度的研究

本文叙述了一种新的测量方法—同位素X萤光背射法,用低能光子源激发稀土矿浆样品,使之产生特征X射线峰和反散射峰。反散射峰的强度与矿浆浓度存在单值对应的非线性关系。浓度越低反散射峰强度越高,由此可直接测量矿浆浓度。它解决了选矿过程中高原子序数介质的矿浆浓度的在线测量问题。这种新的放射性同位素应用技术,与同位素射线吸收法测量矿浆浓度在原理上有着根本不同。目前,此方法未见公开报导。     

负压差散体颗粒无约束屈服强度实验测量方法

根据Ｇｅｌｄａｒｔ－Ａ类散体颗粒在移动床充气条件下气体均匀分布的特点，结合散体和两相流理论，提出理论模型并导出散体颗粒的无约束屈服强度与静态拱宽度的关系式，通过实验测量在负压差条件下与移动床立管联拉的料斗中Ｇｅｌｄａｒｔ－Ａ类散体颗粒的静态拱宽度来计算其鳄出服强度，对于Ｇｅｌｄａｒｔ－Ａ类散体颗粒，此方法的测量结果比Ｊｅｎｉｋｅ有更准确地描述散体颗粒的无约束屈服强度。     

共振散射光谱法测定环境水样中微量铬Ⅵ

研究了在硫酸介质中,铬Ⅵ与碘化物和淀粉形成离子缔合物的共振光散射增强现象,拟定了一种新的测定铬Ⅵ的共振散射方法,确定了实验的最佳测定条件。采用732型强酸性离子交换树脂,可以较好地消除共存离子的干扰。在λex=λem=290nm处,缔合物共振光散射最强,且共振光散射强度与铬(的质量浓度呈线性关系,线性范围为22.3～400μg/L,检出限为6.7μg/L。该方法简便、快速,用于环境水样中铬的测定,相对标准偏差≤0.51%,加标回收率为91%～116%。     

内标元素强度筛选法在激光诱导击穿光谱定量分析土壤标样中铁钛锶的应用

利用激光诱导击穿光谱(LIBS)技术进行光谱定量分析时,由于实验条件不稳定造成的测量结果检出限高、测量精确度低的问题一直是一个亟待解决的难题。实验选取地质矿产部化探分析质量监控站的标准土壤样品为分析样品,以波长为1064nm的Nd∶YAG激光器为激发光源,脉冲重复频率1Hz,通过激光诱导击穿光谱实验装置采集土壤样品在420~440nm范围内的等离子体光谱图。采用以内标法为基础的数据平均处理和内标元素强度筛选法(即以选定的内标元素谱线强度为参考,进行数据筛选)处理数据分别分析了待测样品中的Fe、Ti和Sr元素的含量并进行了对比,利用内标元素强度筛选法测得Fe、Ti和Sr的质量分数分别为68.4mg/g、10777μg/g和75.5μg/g,相对误差由平均法测得的10.60%、3.20%和8.57%降低为2.01%、0.21%和1.95%。说明内标元素强度筛选法处理数据可以减少数据处理量,简化数据处理过程并提高分析精度,尤其适用于激光能量输出不稳定、时间延迟较难控制的实验条件下的物质成分定量分析。     

热带连轧辊型检测中影响因素的模拟实验研究

对热轧现场的各种影响检测精度的因素进行较为详细的模拟实验研究，并分析其对检测结果的影响，对于制定测量策略和数据处理策略，具有现实意义。在模拟工况实验系统中对各种影响测量精度的因素(工况)进行了实验研究，并对实验结果进行了分析比较，得出了各种影响因素对于测试结果的影响。     

亚微米氧化铈颗粒的粒度分布测量研究

采用新的动态光散射及激光衍射等技术对较高浓度悬浮液中亚微米氧化铈颗粒的粒度分布进行了测量,分析了分散前处理对动态光散射测量结果的影响,计算了动态光散射测量时不同分布基础的粒度分布结果,并以透射电镜观测结果进行了验证。结果表明,激光衍射测得的粒度分布结果数值较大,其基于体积分布的粒度中位值约为2μm;动态光散射测量的粒度分布数值较小,基于体积、数量分布的粒度中位值分别为257.0 nm和157.1nm,分散前处理对粒度测量结果有一定的影响;动态光散射测量的基于数量分布的氧化铈颗粒的粒度分布结果与透射电镜观测所得的数值能够较好地吻合。新的动态光散射技术可准确地测量经过充分分散的较高浓度悬浮液中亚微米氧化铈颗粒的粒度分布。     

OpenGL技术及其在地质剖面图绘制中的应用

摘要：论述了OpenGL技术的特点以及主要工作原理，并针对矿山地质剖面图的绘制，提出了在原始勘探地质数据处理的基础上，应用OpenGL技术建立矿体的三维表面线框模型的理论和方法；通过建立矿体三维实体模型，可以从不同角度全方位地观测矿体的空间态势，从总体上控制矿体的空间形态，实现地质剖面图的任意自动剖切。在此基础上设计并开发了基于OpenGL技术的相应软件。该软件可以用来建立矿体三维模型，实现地质剖面图的任意剖切，大大地提高了地质剖面图的准确性和工作人员效率。     

使用散射X-射线的理论强度进行土壤、岩石中微量重元素的X-射线荧光分析

关于土壤、岩石中的Pb,As等微量重元素的X射线荧光分析方法,在求出荧光X射线和散射X射线的强度比,然后制作工作曲线,进行定量的方法已经有所报道.这种方法能够显著地减轻样品固有的矿物效应等因素,达到提高定量分析准确度的效果.然而,近来发展了不仅依据工作曲线,也能依据FP法进行定量的方法.FP法是对定量元素的荧光X射线进行理论强度计算.本文是对散射X射线也进行计算,用于多种样品的定量分析[1].     

辊式矫直机的两种矫直力计算模型对比研究

利用对中厚板辊式矫直机热态矫直时进行的现场力能参数测试的实验数据,把基于“虚拟支点”的矫直力新的计算模型与传统矫直力计算模型进行对比研究。结果表明传统的矫直力计算模型过于保守,新的计算模型更符合实际的矫直力状况。     

Glassy Carbon as an Absolute Intensity Calibration Standard for Small-Angle Scattering

Absolute calibration of small-angle scattering (SAS) intensity data (measured in terms of the differential scattering cross section per unit sample volume per unit solid angle) is essential for many important aspects of quantitative SAS analysis, such as obtaining the number density, volume fraction, and specific surface area of the scatterers. It also enables scattering data from different instruments (light, X-ray, or neutron scattering) to be combined, and it can even be useful to detect the existence of artifacts in the experimental data. Different primary or secondary calibration methods are available. In the latter case, absolute intensity calibration requires a stable artifact with the necessary scattering profile. Glassy carbon has sometimes been selected as this intensity calibration standard. Here we review the spatial homogeneity and temporal stability of one type of commercially available glassy carbon that is being used as an intensity calibration standard at a number of SAS facilities. We demonstrate that glassy carbon is sufficiently homogeneous and stable during routine use to be relied upon as a suitable standard for absolute intensity calibration of SAS data.     

ARefined Model of Three-roller Elastoplastic Asym-metrical Pre-bending of Plate

The geometry of plate after edge pre-bending mode is compared with that after roll-bending mode and the relationship among edge pre-bending angle, pre-bending edge length, and cylindrical desired radius is presented for a three-roller plate bender with bottom rollers adjustable horizontally. The analytical moment-curvature model and springhaek model for pure bending are established, assuming that the stress-strain relationship of material is linear, and the material is in plain strain and yields according to Mises yield criterion. The mathematical model for three- roller edge pre-bending of plate is developed considering the effect of pre-bending edge length, bottom roller radius, friction between plate and roller, etc. The plate tensile test and plate bending test are done and the numerical results agree well with the test data. The results are shown graphically and analyzed in the following aspects： （1） the error between numerical results and test data of top roiler force; （2） the influence of bottom roller radius, relative curva- ture, and bending arc length on springback angle; （3） the relationship between springhack ratio and edge pre-ben- ding angle.     

稀土氧化物熔盐电解过程数学模型的研究

本文对氧化物熔盐电解工艺进行详尽的分析研究，在此基础上对稀土氧化物熔盐电解试验数据分析，建立了氧化钛熔盐电解过程的回归分析数学模型，并结合电解过程对所得方程进行了分析。本文的目的是为了对电解过程进行数学模拟，提高电解工艺控制精度，为实现稀土氧化物熔盐电解自动化控制提供依据。     

混凝土材料对光子散射系数的Monte Carlo模拟

采用EGS5光子—电子蒙特卡罗程序计算了多种能量的光子以多种入射角照射到混凝土上时在各个方向角上所产生的散射系数,分析了模型的形状及材料厚度对散射系数的影响,EGS5模拟所得的散射系数与MCNP程序计算结果符合度较好,相对偏差基本均在5.0%以内。     

Mathematical model for burden distribution in blast furnace

Burden distribution in a blast furnace is vital to its smooth running. However, it is difficult to directly measure the burden distribution for an operating blast furnace. Therefore, mathematical models have been applied to guide the charging process to achieve the desired burden distribution. The accuracies of such models depend on the prediction of falling curve, stockline profile formation, and burden descent mode. In this study, a new stockline profile formation model is proposed in which new equations have been developed for the inner and outer repose angle by considering the influence of the burden flow's vertical and horizontal velocity at the apex of the stockline profile. Validation of this new stockline profile formation model is provided through comparison between calculated results and experimental data for stockline profile. A stepped burden descending strategy, in which the burden would descend through a specified distance after each ring charging process, is proposed corresponding to the successive charging process. The influence of the burden descending strategy on the falling point, the final burden profile and radial depth ratio of ore to coke is also analysed. The result shows that the burden descending strategy greatly affects the final burden distribution, especially in the peripheral region.     

Measured molecular coherent scattering form factors of animal tissues, plastics and human breast tissue

Photon scattering angular distributions from various animal tissues were measured at two energies of a monochromatic synchrotron x-ray beam. Two plastics and human breast tissue were also measured. From these two measurements, the molecular coherent scattering form factor of each material was extracted. A new data analysis technique that uses Monte Carlo based corrections for air scattering, incoherent scattering and multiple scattering was used. The form factors of the 16 materials are presented in tabular form, suitable for use in computer calculations.     

Shielding of crack tips by inclined pileups of dislocations

A mathematical formulation is developed for a long crack (mode III) with two symmetrical screw dislocation pileups inclined to the crack by an angle φ. Dislocation free zones (DFZ) are allowed at the crack up. The resulting series of equations are solved numerically. The effect of the inclination angle φ on the interaction of the crack and the pileups and on the size of the DFZ is examined. These effects appear to be strongest around φ = 45°.     

The formation of ordered δ′-phase in AlLi alloys by diffuse and small angle neutron scattering

The formation of the L1₂-ordered δ′ precipitates is investigated in AlLi alloys by neutron small angle scattering and by diffuse scattering techniques especially near the [100] ordering wave vector. A comparison of the results obtained gives no evidence for disordered Guinier-Preston zones at low temperatures, in contrast to recent suggestions in the literature. A scaling analysis was applied to the structure function characterizing the small angle scattering data. The results show that the scaled structure function for the higher concentrated Al-10.7 at.% Li alloy is narrower in Q-space than for the Al-8.0at.% Li system. The structure function therefore depends on the concentration but not on the annealing temperature, within the range investigated in this experiment. The narrowing of the structure function near the middle of the miscibility gap indicates the presence of correlations of longer range occurring for more symmetric alloys with respect to the phase diagram.     

Mathematical modeling of sulfide flash smelting process: Part II. Quantitative analysis of radiative heat transfer

A mathematical model has been developed to describe the rate processes in an axisymmetric copper flash smelting furnace shaft. A particular feature of the model is the incorporation of the four-flux model to describe the radiative heat transfer by combining the absorbing, emitting, and anisotropic scattering phenomena. The importance of various subprocesses of the radiative heat transfer in a flash smelting furnace has been studied. Model predictions showed that the radiation from the furnace walls and between the particles and the surrounding is the dominant mode of heat transfer in a flash smelting furnace. Formerly Graduate Student, Department of Metallurgical Engineering, University of Utah.