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 If a piece of information is incorrect, a link outdated, or the presentation choppy or unclear, the user can just click "Edit Page" at the bottom and then fix the mistake.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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XRD X-Ray Diffraction (Crystallography, powder camera, XRF)
XRD discussion topic.
How about one FDA approved instrument that contains an 20/30 kVp X-Ray source, Goniometer, crystal holder, HV section, detector holders, timers, X-Ray shielding, and sits on a
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GEOelectronics@...
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#134
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Re: Meteorites
This picture is of a different Si-PIN + electronics stack being tested on the same jig. This one is set to 214K temp. The scan after only 60 seconds. Same Fe-Ni meteorite.
Since the earlier tests the
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GEOelectronics@...
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#133
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Re: OK Dude, how do we excite those RE's above 50 keV cleanly and how to detect it.
On that one shown, yes there is uranium, but not enough to notice by XRF compared to the huge niobium content. Enough to make the Geiger counter (pancake probe) go nut but not enough to analyze with
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GEOelectronics@...
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#132
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Re: OK Dude, how do we excite those RE's above 50 keV cleanly and how to detect it.
Oops had that backwards not a lot of Ta, Nb dominates. Makes it look like a samarskite.
Dud
From: [email protected] [mailto:[email protected]] On Behalf Of Coats-Mine-Petaca-Columbite-w-Ta.jpg
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Dude
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#131
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Re: OK Dude, how do we excite those RE's above 50 keV cleanly and how to detect it.
Hmm no U or Th? Not a lot of Nb. This would be a good Ta Coltan ore if the T is 30%
Dud
Sent: Sunday, November 3, 2019 1:21 PM
To: [email protected]
Subject: Re: [XRF] OK Dude, how do we excite
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Dude
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#130
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Re: OK Dude, how do we excite those RE's above 50 keV cleanly and how to detect it.
Here's one from the Petaca District showing Nb plus definite Ta. It was labeled as Columbite-Tantalite, by the collector.Nb K's 16.61/ 18.62, while the dark blue ones to the left are Ta Ls
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GEOelectronics@...
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#129
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Analysis of a neutron activated down-hole well tool part.
Normal Gamma Spectroscopy with a CZT crystal sows significant Co-60 present, due to nuetron activation of the base metal.XRF reveals most is tungsten (840 keV and 9.67 keV L lines)More analysis and
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GEOelectronics@...
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#128
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Re: Gas Purge vs Vacuum
Will look up dry N2 Randall, thanks
Geo
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GEOelectronics@...
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#127
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Re: Gas Purge vs Vacuum
Hi Geo,
You don't need a high vacuum so a small, 12VDC pump would probably be sufficient
and eliminate 70 to 80% of the ambient air.
Plus if you incorporate two or more pump down cycles with a dry
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Randall Buck
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#126
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Re: Gas Purge vs Vacuum
This one is another gas purge experiment, this time instead of a hydrocarbon, it's a N+O mixture. More aimed at eliminating the Ar peak ~3 keV with simple equipment.
Two scans of sub gram chunk of Yb
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GEOelectronics@...
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#125
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Re: OK Dude, how do we excite those RE's above 50 keV cleanly and how to detect it.
sent in private email, ask if questions. Geo
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GEOelectronics@...
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#124
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Re: OK Dude, how do we excite those RE's above 50 keV cleanly and how to detect it.
Ok looks like a columbite.
I have the AMPTEK software and some of the .mca files. But there are no notes as to what the .mca spectra were obtained from. I need the field notes describing what rock
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Dude
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#123
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Re: OK Dude, how do we excite those RE's above 50 keV cleanly and how to detect it.
No Ta could be definitively identified. Later in the day yesterday ran pure Ta metal, no problems, just to verify the correct peaks.
When you download and activate the free AMPTEK software, I'll
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GEOelectronics@...
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#122
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Re: OK Dude, how do we excite those RE's above 50 keV cleanly and how to detect it.
Look for Tantalum in that as it might be Coltan Nb/Ta U. Yep the low end is a mess when you get into a rock matrix. Fe, Ti, and Mn should be ban from the XRF periodic table in my opinion
Dud
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Dude
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#121
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Re: OK Dude, how do we excite those RE's above 50 keV clkeanly and how to detect it.
Randall,
The Laser Induced Breakdown System (LIBS) I put together uses a Quantel Brilliant 360 mJ 1064nm Q-switched laser with a 4ns pulse and up to a 10 hZ pulse rate. I delay the Q-switch and run
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Dude
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#120
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Re: OK Dude, how do we excite those RE's above 50 keV cleanly and how to detect it.
Dudley, I can start to see what you meant about the clutter at the low end. Testing a nice (what I think is) Columbite, it has gobs of niobium and uranium. The low end is a mess. Def. need the K's for
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GEOelectronics@...
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#119
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Re: OK Dude, how do we excite those RE's above 50 keV cleanly and how to detect it.
Hi Dud,
Nevertheless, very nice bit of apparatus.
What kind of laser are you using, solid state ?
Randall
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Randall Buck
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#118
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Re: OK Dude, how do we excite those RE's above 50 keV cleanly and how to detect it.
Hi Randall,
Yes you never know what state you may be looking at and the ion abundances are different. Are you referring to Ritz vs Observed wavelengths?
Lines will move up very slightly with an
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Dude
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#117
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Re: OK Dude, how do we excite those RE's above 50 keV cleanly and how to detect it.
Hi Dud,
Don't you have to pay attention to ionization states greater than one and the consequent line shift, when using LIBS ?
Randall
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Randall Buck
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#116
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Re: OK Dude, how do we excite those RE's above 50 keV cleanly and how to detect it.
Less than 1 gram of Eu Oxide, powdwered, inside a plastic baggie 62s
Show L and K shells and the drop off of efficiency as energy rises.
Si-Pin. @59.5 X 8
PS I brought this discussion concerning
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GEOelectronics@...
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#115
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