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 If a piece of information is incorrect, a link outdated, or the presentation choppy or unclear, the user can just click "Edit Page" at the bottom and then fix the mistake.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 Groups.io 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 Groups.io:?
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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Re: Xrf old faucet
First being shown is Taray's "Tap sediment end.mca) loaded into live_data_2 and showing as? solid red
peaks with the "Tap brass.mca" loaded in live_data_1 with its peaks showing as black outlines. If the user wished to see only one set of peaks, the other ones would have been set to H for HIDE instead of left with no letter in the front. If set up that way, you can animate them back and forth with keystrokes. Sometimes overlaying the peaks is too busy to be effective. I've highlighted different peaks, especially the Pb Ka1. It will be clearer in the second picture what a big difference there is at 10.55kev between the scans. To me this would definitely raise a red flag for Pb but at this stage is not definite enough to call it 100%. Further testing would be merited and could swing it one way or the other. All colors are set by the user as is their intensity (# of pixels) Notice at the top of the display it is showing the name of the active .mca file. When we change the other file to being active instead, this will change to that file name. Now the same two scans, but switched with the outline becoming solid red and vise versa. To me the 10.55keV difference is much clearer in this setting. Close but about half a channel off Pb However below see how we can expand down to 1 keV full width (less is possible, and this scan was taken with only 2048 channels, we can do up to 8k channels for even better resolution but longer scan time). 1 keV = 1000 electron-volts. Look how many individual peaks can be inside a single keV. Have fun? Geo |
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Re: Xrf old faucet
?NOTE: on Library File attached, change .txt to .lib and store on your computer in the Amptek LIBRARY folder. Load into your DPPMCA program using ANALZE then ADD LIBRARY on the top menu line.
Groups.io rejects messages with .lib suffix for some reason, they think is an executable file. Great scan Taray, there is no interfering from the exciter! The main peaks are well placed and perfectly calibrated. Shown in pic is the auto-analysis I did, all main peaks were identified but I had to add Zn-Kb1 it was too small for auto ID. Also shown are the steps to? set up your own auto ANALYZE function. Geo |
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Re: Xrf old faucet
taray singh
Hi guys
I have? some reservations against using any plastic mounts? near my Xray beam, So I repeated with some layers of surgical tape? with cardboard base. Next time probably just the cardboard base. Even white surgical tapes may have some zinc oxide coat which I did not notice in my? ?tape scan Repeated at 3 different sides. There is chromium noted probably coming from the coating. The tap sediment end may be showing some traces of lead Thanks Taray |
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Lead in drinking glass
taray singh
Hi guys
? ? ? ? ?I scanned a free gift tall decorated glass. ? ? ? ? I have been drinking from it for years . ? ? ? ?This particular one is partially broken? and ended in my lab as a holder?? These tall and narrow? glasses? are rather unstable and many have accidentally broken thankfully. ? ? ?So? decided to scan this broken? one hoping to? ?pickup? elements like Ba etc ? ? Surprisingly? found lead instead ? ?On further reading , drinking glasses can contain harmful levels of lead in the decorative enamel. I scanned from bottom(no designs) and from the sides? as a comparison. Only the? painted enamel side show? lead Beware of decorative glasses Scan everything under your nose Taray |
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Amptek Si-PIN at 0-100 keV range
Recent Si-PIN Gamma Spectrometry studies of different types of uranium has shown up some puzzling peaks up around 58-59 keV. Nothing in the databases shows anything to be at the those exact energies, and we all know that uranium has strong peaks above 60 keV- the normal top range of my previous Gamma and XRF scans.
That led to expanding the upper range on the Si-PIN detector which is accomplished by lowering the GAIN, then recalibrating. Using the 59.5 from Am, you can move the peak down to wherever it needs to be from it's normal position near the right edge (high energy) spot.? Icon buttons 27 thru 30 do that. 27 and 28 set the increment of the steps of change make, while 29 and 30 increment up or down by the selected increment. This test with a Spectrum Techniques? Ba-133 calibration disk shows the result. It's being show in both LINEAR and LOGARITHMIC graphical mode to show how each has it's merits. Another function of this test is to demonstrate what using the 81keV Gamma Ray of Ba-133 as an exciter will give you to deal with down at the low end when XRF'ing. For those using DPPMCA, you can print out the first picture to use as a reference when we discuss the Icon Panel controls. When looking at either the LINEAR or LOG display, always keep in mind that the height of the peak is governed by 2 distinct factors. #1 is of course the actual intensity of the radiation making that particular peak and #2- and more important- the point on the energy-efficiency curve that the peak occupies. Two peaks that look early the same in LOG display may be nowhere near the same in LINEAR mode. Si-PIN for example falls off rapidly over 25 keV, as you can plainly see there is life up above 60keV! I put together a .lib file just for Ba-133, which is also attached along with the .mca file for this test. EDIT: Groups.io bounced thisl? library file so it's now a txt file, change the suffix to dot-lib when you download it to your AMPTEK LIBRARY foder. Have fun Geo ? |
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Re: My Si-pin happy in its new home.
That would be nice.? Hearing rumors even here in San Antonio of new or repeat major social lockdowns coming up.? Going to an event at the zoo tomorrow, just in case... On Thu, Nov 12, 2020 at 11:56 PM <GEOelectronics@...> wrote:
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Adding another Medium Energy probe to the lineup.
Pictures of the 3rd CdTe for the XRF lab.
This one is assembled from parts, all by Amptek. Everything was tested before assembly and the sensor is one I picked up on eBay a few years ago and has been in storage until today. Right now it is a backup for the other two but can be put on line with a PX power supply and Amptek MCA8000D if needed. Geo |
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Re: Xrf old faucet
Here is the case, sale at $19.99. Yes, it's been interesting reading everyone's test reports!? I think I got one of your Cs calibrated soil samples a few years back.? I really do need to organize... I was working on the 100 amp service into the shed yesterday and took some pics with my thermal imaging camera.? The corrugated steel outer skin (it's TX!), compared tot eh areas with sheathing and 3.5" of polyiso insulation installed, and then areas with the interior radiant barrier sheathing installed.? Very interesting. On Thu, Nov 12, 2020 at 11:07 AM <GEOelectronics@...> wrote:
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Re: Xrf old faucet
You guys are making me want to hurry up and get some projects done so I can play with my setup! By the way, Home Depot right now has a padded foam travel case on special purchase for $19.99 that is the perfect size to carry/protect the Amptek unit, power supply, some exciters and misc calibration sources. On Thu, Nov 12, 2020 at 10:35 AM taray singh via <sukhjez=[email protected]> wrote:
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Nick Andrews
