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This document provides an overview of X-ray diffraction (XRD) and X-ray fluorescence (XRF) techniques. It discusses the principles, methods, applications, advantages, and limitations of both XRD and XRF. XRD is described as a technique that uses X-ray scattering from crystalline materials to determine their atomic structure, while XRF involves bombarding a material with X-rays and analyzing the characteristic secondary X-rays emitted to determine its elemental composition. A variety of applications are outlined for each technique in fields such as materials science, geology, and chemistry.
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X ray
- 1. X ray Author: Md. Waliullah Wali Dept. of pharmacy Southeast University
- 2. Outline LOGO X-ray diffraction Principles of XRD XRD Techniques Applications of XRD Limitations of XRD YOUR SITE HERE
- 3. LOGO X-Ray Fluorescence Principles of XRF XRF Techniques Applications of XRF Advantages & Limitations of XRF YOUR SITE HERE
- 4. XRD LOGO X-ray diffraction (XRD) is an analytical technique looking at X-ray scattering from crystalline materials. Each material produces a unique X-ray "fingerprint" of X-ray intensity versus scattering angle that is characteristic of it's crystalline atomic structure. X-ray diffraction procedures apply only to crystalline Materials. YOUR SITE HERE
- 5. Principles of XRD LOGO X-ray diffraction is based on constructive interference of monochromatic X-rays and a crystalline sample. The interaction of the incident rays with the sample produces constructive interference (and a diffracted ray) when conditions satisfy Bragg's Law (nλ=2d sin θ). YOUR SITE HERE
- 7. XRD Techniques LOGO YOUR SITE HERE
- 8. XRD Techniques LOGO YOUR SITE HERE
- 12. Applications of XRD Determine crystal structures -Characterization of crystalline materials -Identification of finegrained minerals -Determination of unit cell dimensions -Measurement of sample purity LOGO Determine of modal amounts of minerals Make textural measurements YOUR SITE HERE
- 13. Limitations of XRD LOGO Homogeneous and single phase material is best For mixed materials, detection limit is ~ 2% of Peak overlay may sample occur and worsens for high angle 'reflections' Requires tenths of a gram of material which must be ground into a powder YOUR SITE HERE
- 14. XRF LOGO X-Ray Fluorescence is defined as “The emission of characteristic "secondary" (or fluorescent) X-rays from a material that has been excited by bombarding with high-energy X-rays. The phenomenon is widely used for elemental analysis.” X-ray fluorescence procedures applied to the material in any physical state, solid, liquid and gas. YOUR SITE HERE
- 15. Principles of XRF LOGO The XRF method depends on fundamental principles that are common to several other instrumental methods involving interactions between electron beams and X-rays with samples, including, X-ray spectroscopy (e.g. SEM – EDS), X-ray diffraction (XRD) and wavelength dispersive spectroscopy (microprobe WDS). YOUR SITE HERE
- 16. XRF Techniques LOGO YOUR SITE HERE
- 19. Applications of XRF LOGO -Research in igneous, sedimentary, and metamorphic petrology -Soil surveys -mining -Cement production -Ceramic and glass manufacturing -Environmental studies -Petroleum industry -Field analysis Bulk chemical analyses of major elements (Si, Ti, Al, Fe, Mn, Mg, Ca, Na, K, P) in rock and sediment Bulk chemical analyses of trace elements (in abundances >1 ppm; Ba, Ce, Co, Cr, Cu, Ga, La, Nb, Ni, Rb, Sc, Sr, Rh, U, V, Y, Zr, Zn) in rock and sediment YOUR SITE HERE
- 20. Advantages of XRF LOGO Minimal preparation Nondestructive Fast Easy to use Costeffective YOUR SITE HERE
- 21. Limitation of XRF LOGO 0 Relatively large samples, typically > 1 gram Materials that can be prepared in powder form and effectively homogenized Materials containing high abundances of elements for which absorption and fluorescence effects are reasonably well understood Materials for which compositionally similar, well-characterized standards are available YOUR SITE HERE
- 22. References LOGO 1. Elements of physical chemistry by S Glasstone 2. Atkins physical chemistry 3. Pharmaceutical chemistry by LG Chattem 4. Brady, John B., and Boardman, Shelby J., 1995, Introducing Mineralogy Students to X-ray Diffraction Through Optical Diffraction Experiments Using Lasers. Jour. Geol. Education, v. 43 #5, 471-476. 5. Brady, John B., Newton, Robert M., and Boardman, Shelby J., 1995, New Uses for Powder X-ray Diffraction Experiments in the Undergraduate Curriculum. Jour. Geol. Education, v. 43 #5, 466470. 6. Buhrke, V. E., Jenkins, R., Smith, D. K., A Practical Guide for the Preparation of Specimens for XRF and XRD Analysis, Wiley, 1998. YOUR SITE HERE
- 23. LOGO Any ? Thank All of you! YOUR SITE HERE