XRF Wiki
Welcome to the XRF Wiki. This Wiki is a repository of information contributed by members of [email protected]. Members can view and edit the pages. The pages are currently not viewable by the public. The pages below represent a rough overview of the technology and techniques associated with X-Ray Florescence Spectroscopy as well as serving as a place for members to organize the spectra that they have contributed to the forum.?
As a starting point, the pages will be populated by information taken from member posts from the past few years - with references/attribution. Perhaps in time, these pages can be edited by members to make them more complete and less choppy. Members can also edit this page, making the structure of the content more organized.?
Pages can contain information about a particular topic, links to relevant resources (such as manuals, research papers, etc.), links to relevant forum discussions on the topic, book titles, or anything that might be useful.
What follows is very much a work in progress.
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Adding to the Wiki
For those unfamiliar with the Wiki phenomenon, it is basically a user editable encyclopedia. The idea is that there are pages with different articles, which the user can read and also choose to edit if desired. If a piece of information is incorrect, a link outdated, or the presentation choppy or unclear, the user can just click "Edit Page" at the bottom and then fix the mistake. There is also a "Page History," so if you a user were to make a mistake or maliciously destroy a page (which wouldn't happen here) an editor can come along and restore the page to a previous version.?
If you have used MediaWiki (the engine that runs behind the scene of Wikipedia.org) you will be familiar with a certain style of creating an article. There are tags that one uses to change the formatting of the parts of the article. The Wiki on 开云体育 uses a different background engine and so the standard MediaWiki syntax does not apply here. Rather, the page is edited using the same tools as one would use to compose a message on the forums. If you are a programmer or someone who likes using the tagged syntax directly, you can access the underlying page source code, be activating the advanced editing toolbar (the icon with three lines on the far right of the basic toolbar) and then clicking on the source code icon <> on the far right of the Advance Editing Toolbar. You will immediately notice that the underlying source code is HTML. Most things can be done just by using the various icons, but advanced features like table can only be implemented by manually writing the source code. (Although there are website available that will generate the source code for you through a graphical interface.)
Here are some useful resources from 开云体育:?
Wiki Guide for Users and Editors
Message Composition Tips and Tricks
Overview of XRF
X-Ray Florescence vs. X-Ray Diffraction
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Hardware
This section describes the hardware used for XRF. We will describe the basic theory of operation of each stage in the processing tool chain and then present different commercial systems that are available as these systems are often integrated together.
[Editor note: General theory needs to be in an independent page separate from specific manufacturer information.
[Editor note - question: Should this be arranged by category, e.g detectors, preamps, etc or by manufacturer with the manufacturers product line on one page. Perhaps it's best to put a list of products with theory but the details of the products on a manufacture page...]
Detectors?- what's available, theory of operation, tradeoffs
Detector Cooling?- keeping detectors cool to avoid thermal noise and keeping the TEC from overheating
Preamps?- theory of operation, brief summary of what out there (and what not to do - such as trying to use a PMT preamp for a SiPIN diode...)
Pulse Processing Theory - high level overview of the stages of going from detector pulse to channel peaks on the computer
Commercial Systems - many commercial systems are integrated so it seems to make sense to present, for example all Amptek products together. [question: are their other affordable integrated systems besides Amptek?]
Amptek XRF System
Activation Sources - what do you use to make the sample fluoresce (that's within the amateur budget and doesn't require special licensing)
Software
- Device Control Software - what do you use to collect the data from the detector system
- XRF Analysis Software - what do you use to analyze the data, especially for quantitative measurements (composition percentages, thin film measurement)
- Free Software Tools
Note: there may be software packages that possess some or all of these characteristics.
Materials Spectra
Metals Spectra
Historic/Archeological Spectra
Reference Materials Spectra
Household Objects Spectra
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Resources
Videos
Articles
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Non-XRF Techniques
Gamma Spectroscopy
Raman Spectroscopy
FTIR - Fourier Transform Infrared Spectroscopy
Atomic Emission Spectroscopy
Inductively Coupled Atomic Emission Spectroscopy
Spark Emission Spectroscopy
Atomic Absorption Spectroscopy
LIBS - Laser Induced Breakdown Spectroscopy
Photoacoustic Spectroscopy
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Pure metals for calibrations and experiments
I was looking at buying some silver yesterday from JM Bullion and noticed they have 1oz bars of other metals. I ordered ytterbium, yellow niobium, iron, and molybdenum and a 1-lb copper bar, along with silver coins and goldbacks. They have a deal for new customers, you can buy 10oz of silver at spot rate which is a good deal. And free shipping. As well as what I ordered, they also sell purple niobium, tantalum, and some other more exotic elements too. Likely will order those at a later date. The purple niobium was out of stock.
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FYI An XR generator, new, 20-75kV $500...Something I don;t know anything about.
FYI, no connection to seller, "no shipping", so not practical but this is something new to me and would have some possible use if we knew more: 254370244711 Geo
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European powders, colors
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I bought this just for fun. I wonder if a scan of the powders will reveal what else is in the compounds for different colors. https://www.ebay.com/itm/281970344585?mkcid=16&mkevt=1&mkrid=711-127632-2357-0&ssspo=kjFjGo9nT1-&sssrc=2349624&ssuid=9S4jfnnKS4i&var=&widget_ver=artemis&media=COPY
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Hi guys Here I have a meteorite specimen I bought from eBay more than 5 years ago .It was sold as a Zag meteorite which hit Moroccan Sahara in 1998. Apparently there many episodes of meteorite falls there which go undeclared. Perhaps that is why I got it. It weighs about 7 gms and about an inch wide . I really think it is not a “meteorwrong” cos 1 Brown crusty outer layer due entry into earth’s atmosphere with a lighter shade within . 2 It is quite magnetic for its small size Furthermore it’s looks very similar to samples on the net .Possibly a H3-6 Breccia. I believe it is a stony iron /nickel silicate minerals consisting of free iron/nickel and silica among other elements I examine it under a light microscope which show free metal interspersed with rock .Due to the 3 dimensional nature I focused on selected areas only Only a thin section will reveal more . There could also be some halide compound within but I am not able to visualize it My xrf analysis with Am241/Bicron X-ray detector show iron consistent with my magnet and light microscopy Gamma spectrometry was negative probably due to the small size .Meteorites can be radioactive though Thank you Taray
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Hi guys In dentistry traditionally a metal alloy mixture is mixed with liquid mercury in a amalgam making machine . Looks like a small coffee machine. This method is still used today Newer methods are by using special amalgam capsules . Here is a file of the grey metal alloy mixture minus the mercury. Copper and silver noted Thanks Taray P.S The mca file will follow on reply
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Links to handy XRF Spectrum lookup tables.
XRF Spectra (xrfresearch.com) Geo
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Geo, Here’s a shot after struggling with trying to get the detector loaded with LN2. The dewar dip stick had a problem and low pressure so it took quite a while to fill 5L and the I checked the LN2 burn rate by measuring weight loss over several days. It will last 4.9 days which is at spec and allows camping field work without have to lug around a 30L dewar which won’t fit in the 4 runner anyhow . The detector is a Canberra Broad Energy carbon window HPGe. This calibrate was done using the ISOCS modeling program for a point source located 3.25” from the detector face. I didn’t have enough time to get it set up in the shield / collimators as I was running out of LN2 at that point so it’s got some background U and Th in the spectra due to REE samples laying around. The other file is aGAD6 Thorium Energy cal disk. No stated activity but it looks like they got some u in there as well. Dud From: [email protected] [mailto:[email protected]] On Behalf Of GEOelectronics@... Sent: Friday, February 12, 2021 4:58 PM To: [email protected] Subject: Re: [XRF] Xrf coffee ground Hey Dud, how did the Ln2 project go? Got some results to post? Geo
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When this group is out of memory, move to XRF-Page-2
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We'll try to limit the size of our picture posts, and try to NOT repost pictures in your replies. Also without the WIKI, we may get along fine. your host, George Dowell Geo Group Email Addresses * Post: [email protected] * Subscribe: [email protected] * Unsubscribe: [email protected] * Group Owner: [email protected] * Help: [email protected]
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Hi guys Here is an repeat xrf of my office coffee . This time with x ray source KV 60 MA 0.1 Exposure time about 5 secs ALARA protections taken The peaks are Fe,Ni,Zn and possibly rubidium The Fe/Ni could be from any stainless steel heating element during roasting or brewing plus naturally existing. Ni is a concern since some of us including myself have nickel allergy. There appears to be lots of noise on the left? Kindly pm any questions regarding setup Taray
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X-ray emission spectra from a tungsten target produced at 100 kV. Curve 1 is the theoretical spectrum without any filtration. Curve 2 is the typical spectrum with the inherent filtration of the x-ray tube and added filtration. Curve 3 shows the effect of additional filtration.
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Phase II Now moving on to OTHER excitation. Transferring our new-found technical knowledge to other sources of excitation, basically starting all over from the previous TUBE tests. First up- AmX1 Amptek Si-PIN 25mm^2 NO Collimator, but a Kapton safety cap. Source pointed straight up, sensor is at 90 degrees to the source beam. Sample intersects the beam at 45 degrees. Pretty much a standard setup, to establish a baseline. Geo
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The sample is Rainbow Hematite, weight 5 mg. Longest dimension is about 1mm, thickness is a fraction of that. Like a flake. It was a free sample from a supplier, as shown in the watch glass, a total of 0.065g, from dust to small flakes. The sample holder today is a punched disc of cardboard (3X5 card, extra heavy) with a central hole punched to hold the sample. A piece of clear Scotch tape covers the hole from the back side and onto the sticky side of that we affixed the sample, in the middle of the hole. Over the top of the sample is a cover layer also of clear Scotch tape. The idea was to be able to see through the sample holder to get it positioned over the 1mm hole in the collimator. It works but next time I'll make the hole in the middle larger for better viewing through it.. The picture is of the sample holder ready to be positioned in the XRF tester stand. I can report that the holder works fine at the energies we are using for this test series (Fe Ka1 @ 6.40keV, Fe Kb1 @7.06keV). We are testing the equipment assembled into our current XRF demonstrator. as well as the optimum level of energy in the beam required to produce specific results. On the beam port is a 1mm shielded collimator, on the detector, an Amptek Si-PIN, is a tungsten collimator with a 1mm hole for a window. Geo
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Skimming angle XRF- Experiment This came up in a discussion so here's an experimental setup to test the principle. The idea is that no matter what angle the exciting energy arrives in relation to the atom, or the surface of the material, that the resulting characteristic X-Ray can leave the material isotopically, that is without regard to direction, as if from a point source. Skimming angle refers to those rays that happen to leave along the surface of the material. In this setup the highly collimated beam hits the surface of the copper target at right angles (perpendicular). There the beam is about 2mm wide. Characteristic X-Rays emissions are sampled from the far end of the material, with the detector also highly collimated, with a tungsten shield with a 2mm central hole. An Amptek Si-PIN detector and DPP5 MCA is used to record the results. The setup- really the only difference compared to normal is the target would usually be at 45 degrees. A closeup of the bottom of the Cu target and the angle the rays have to go to reach the detector through the tungsten shield, over an inch away.... The funny thing is, it actually works! Not only does it works but the display is remarkably clean of interference..... Geo
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Hi guys Two common ways for Am241 housing is coaxial and converging plates Here is an another way I am toying round. Using radionuclide lead pigs I manage to squeeze 4 buttons and made a pair The advantage is mainly when using small samples where they can be placed very close to the Am beam I installed iphone app to resize photo Taray
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This 开云体育 memory problems
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Yesterday I tried to upload some documents concerning the Tel-X-Ometer and its copper target tube generator, the whole post was rejected by the system with a warning about exceeding the free memory limits of this group. Come to find out there is only 1GB free of cost. Not much for a pictures based discussion. So please try to limit the size of the pictures, and when replying to a post with pictures, learn to to so without repeating the pictures unless is is important to the discussion. Now I'm going back to the beginning post and manually removing the repeated pictures to hopefully buy us some time before we have to move the XRF-PAGE2 group and archive this one. If members can do this themselves for their own posts it would be welcomed. Shades of our original groups on Yahoo much? PS there is a monthly fee of $20 for an extra 9GB but I'm personally in no position to fund that for 15 groups! Geo
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Hi guys Pharmaceuticals have some active ingredients but their main components are fillers. These fillers have some functions which are not necessarily therapeutic but can influence the tolerance to a drug. But they can be used for identification of manipulated products such as presence of inorganic compounds especially in some generics. As a reference I have provided a micro xrf lab results of a sample of Aspirin Baeyer original and a generic. The generic filler has more inorganic compounds compared to the original Pb is astonishingly present in the generic Unfortunately Pb residual peaks makes it difficult to make an analysis regarding the presence of lead with Am setup Here I am using generic form of clopidogrel a common antiplatelet medication better known as Plavix My sample is a few tablets in a polyethylene container. Ideally should be ground to a flat sheet for xrf Anyway my xrf show peaks of Ti and Fe like the lab results Best stay away from generics for long term usage drugs Taray
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Wavelength Dispersive X-Ray Fluorescence Spectrometer (WDXRF Spectrometer)
Up until now, the main subject being discussed on this group has been technically called ED-XRF. The ED is for energy dispersive. Specifically simultaneous ED, since the excitation produces a spectrum of electron shell transition energies, from which we derive the individual energy peaks all at the same time with our sensor. There is no reason in the world that an enterprising young amateur scientist couldn't do essentially the same thing manually, using a very simple SCA (single channel analyzer), analyzing the important energy peaks one step at a time. https://randomuseless.com/spectra/spectra.html In this thread we will explore and discuss yet another manual sequential method called WD-XRF for Wavelength Dispersive-XRF. in which we can analyze crystal structures and have better access to the lowest energy element's identity. Have fun, Geo
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HI guys Before doing this xrf .I knew little about timing belts and how they actually function. I thought made of just plain rubber or something like that until my car timing belt almost snapped on the freeway weeks ago. Replaced a new one together with the full timing belt kit. Kept the old stuff for xrf. Xrf was pretty short because the peaks were appearing and therefore I decided no need for a longer scan. Xrf with Am 241 show iron and zinc peaks. On further reading noted that these belts are made of rubber reinforced with fibreglass,steel or neoprene. Most likely the iron is in the cords and zinc as neoprene in the rubber Pics are for a section of the timing belt exposing the cords and mca . Thanks Taray
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Hi guys Vanadium is quite an elusive element and rarely makes a solo appearance in xrf spectrum Usually associated with Fe,Cr or titanium alloys Used in implants and tools etc The very fact it lies between Ti and Cr with closely resembling peaks makes it quite indistinguishable. My attempts to capture V peaks clear cut has failed before. Today I placed a few grams of almost pure V in a small polyethylene container . The peaks for V are noted together with Fe probably impurities. My sample is not magnetic, testing with a strong Nd magnet A comparison spectrum of empty polyethylene containers show some residual Pb like in the V spectrum Pics for vanadium ore ,vanadium spectrum and V/ polyethylene mca Taray
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Sat 8:39am