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 If a piece of information is incorrect, a link outdated, or the presentation choppy or unclear, the user can just click "Edit Page" at the bottom and then fix the mistake.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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When this group is out of memory, move to XRF-Page-2
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 *
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GEOelectronics@...
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#2179
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Re: Xrf coffee ground
Hi guys Ludlum 12S??is??my favorite. Yes the readings are not accurate. Actually for low energy x rays ,they overestimate due to energy response curve calibrated to Cs137,advantageous for me.
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taray singh <sukhjez@...>
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#2178
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Re: Xrf coffee ground
Geo, 1 frustrating week of trying to get a 30L dewar to fill a BEGE detector. Only got 3 psi and it would drop to zero on trying to fill the detector. Had a bad dip stick seal in one withdrawal device
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Dude
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#2177
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Re: Xrf coffee ground
Hey Dud, how did the Ln2 project go? Got some results to post?Geo
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GEOelectronics@...
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#2176
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Re: Xrf coffee ground
No, the 12S is not a good instrument for that application. It only reads dose rate correctly when calibrated for Cs-137. All other energies are wrong. The proper instrument would be a Ludlum 17
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Dude
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#2175
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Re: Xrf coffee ground
For DETECTING the Ludlum12S is hard to beat, and is a good instrument for your application. I used a similar instrument to track down a defective industrial X-Ray machine at a factory in an industrial
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GEOelectronics@...
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#2174
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Re: Xrf coffee ground
Taray, Be careful with X-ray tubes as they have a very broad energy range with a very high dose rate. The Ludlum12s is not an appropriate instrument to measure the dose rate with as its response is
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Dude
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#2173
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Re: Xrf coffee ground
Tube tech is simple. The beam is combination of Bremsstrahlung X-Rays from the electron beam stopping on the target and XRF from the tungsten (or other target) caused by the electron stream. Same Ka
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GEOelectronics@...
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#2171
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Re: Xrf coffee ground
Geo Unlike Am241,I am not familiar with the X-ray xrf??spectrum yet Yes I will stack if I have to go beyond 3 secs to cool off. Regarding Br ,it is coming ?likely?from the coffee The
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taray singh <sukhjez@...>
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#2170
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Beam "hardening"
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
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GEOelectronics@...
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#2169
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Re: Xrf coffee ground
Thanks for that analysis Taray. We should keep quite about the free vitamins that are unknowingly being included in coffee, they will raise the price!(joke). A few real ideas - We can see clearly on
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GEOelectronics@...
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#2168
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Re: Xrf coffee ground
Hi guys No analysis is complete without a control Here is an xrf of the? same fresh coffee beans (partly crushed to make it more homogenous) Wrapped in a thin kitchen plastic sheet. In line with the
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taray singh <sukhjez@...>
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#2167
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Re: Xrf coffee ground
Good for you. I have a 4X5"polaroid film holder, will FUji version fit? also 4x5 cut film (negative) and regular X-Ray film holders too. To: [email protected] Sent: Thursday, February 11, 2021 6:55:34 AM
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GEOelectronics@...
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#2166
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Re: Xrf coffee ground
GeoYes I did and success.That was one of my preliminary test?I used a green xray scintillation screenAlso venturing into x ray photography with fujifilm polaroid?So far have??not ?got?the right
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taray singh <sukhjez@...>
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#2165
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Re: Xrf coffee ground
Good start...... Looks like your internal filtering is a bit lower than mine, This could be interesting. Can you see the beam with a screen? A gadolinium based screen shows best. Geo To: [email protected]
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GEOelectronics@...
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#2164
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Xrf coffee ground
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
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taray singh <sukhjez@...>
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#2163
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Re: Small Sample Size XRF with low power (OTHER) excitation
If everything transferred and was entered correctly, these is the last steps and you can add oxygen to your paper. Push OK on the EXPRESSION menu now. On your SPECTRA LIST box, HIDE live_data_1 and
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GEOelectronics@...
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#2162
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Re: Small Sample Size XRF with low power (OTHER) excitation
This is the germanium step. *Add Ge to your paper= Bi-N-Ge* Then go to the DPPMCA program's menu bar, press ANALYSIS From the drop down menu, select EXPRESSION, then on the action box add this formula
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GEOelectronics@...
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#2161
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Edited
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Re: Small Sample Size XRF with low power (OTHER) excitation
*Bi-N Now add nitrogen (N) to you paper. * Then load the .mca file live_data_2 into your program. It was made by removing the sample from the jig and running with no sample target for 2 minutes. This
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GEOelectronics@...
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#2160
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Re: Small Sample Size XRF with low power (OTHER) excitation
Enough work, ;let's play a game. The periodic table of elements game. *Bi-* First we do Bismuth. So mark Bi on a piece of paper, then load this file into your DPPMCA program, it should show up on your
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GEOelectronics@...
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#2159
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