Science topic

X-Rays - Science topic

Penetrating electromagnetic radiation emitted when the inner orbital electrons of an atom are excited and release radiant energy. X-ray wavelengths range from 1 pm to 10 nm. Hard X-rays are the higher energy, shorter wavelength X-rays. Soft x-rays or Grenz rays are less energetic and longer in wavelength. The short wavelength end of the X-ray spectrum overlaps the GAMMA RAYS wavelength range. The distinction between gamma rays and X-rays is based on their radiation source.
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Hello,
I am working on a research project that involves detecting cavities or other teeth problems in panoramic X-rays. I am looking for datasets that I can use to train my convolutional neural network. I have been searching on the internet for such datasets, but I didn't find anything so far. Any suggestions are greatly appreciated! Thank you in advance!
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you may have a look at:
Good luck and
best regards
G.M.
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(This also answers the criticism that the natural and the artificial shouldn't be mixed. The discussion takes the view that “natural” and “artificial/technological” are the same thing – and explains HOW they are the same thing)
Let's begin with a statement I read recently, “Special relativity is the most fundamental, and thoroughly proven, theory in all physics.” I won’t question that but I will suggest that we consider quantum gravity (QG). There’s no theory of quantum gravity at present but modern physics seems to have little doubt that we will have a successful theory one day. Despite the enormous success of general relativity, that theory will require adjustments to fit in with QG. Quantum mechanics will also need modifications to fit in, as Einstein realized when he called it incomplete. In all history, there has never been a single theory that could be called 100% perfect in the sense that it explained every detail forever, and never needed refinements – and there will never be such a theory. Our period of history is no different and that other product of Einstein’s brain (special relativity) has brought great advances but must inevitably endure the same fate of being refined.
May I suggest possible modifications to the above theories – not to attempt to compete with quantum mechanics or the relativity theories but merely to demonstrate that refinements of them are conceivable.
First, quantum mechanics –
Reliance on bodily senses – extended to our technology – tells us things and events are distinct and separate. Acknowledging the correctness of this frame of reference means there are countless particles forming the cosmos. Recognizing the truth of a different point of view means these particles are unified by the action of advanced and retarded waves into one particle* - whether it be classified as a boson or fermion (or both). The interpretation of particles being in two or more places at once can be reinterpreted as being in one position i.e. unipositional, from the Latin ūnus meaning one. This unipositioned particle interferes with itself since it’s composed of self-intersecting Mobius strips which, because mass is united with spacetime, account for spacetime’s curvature. Unipositional quantum mechanics also means every particle is entangled with every other.
* "When we solve (19th-century Scottish physicist James Clerk) Maxwell's equations for light, we find not one but two solutions: a 'retarded' wave, which represents the standard motion of light from one point to another; but also an 'advanced' wave, where the light beam goes backward in time. Engineers have simply dismissed the advanced wave as a mathematical curiosity since the retarded waves so accurately predicted the behavior of radio, microwaves, TV, radar, and X-rays. But for physicists, the advanced wave has been a nagging problem for the past century."
("Physics of the Impossible" by Michio Kaku, 2009, Penguin Books, p. 276)
Second, addressing the subjects “non-causal” and “at once” –
All mass is composed of gravitational and electromagnetic waves, according to vector-tensor-scalar (VTS) geometry inspired by the title of Einstein's 1919 paper "Do gravitational fields play an essential role in the structure of elementary particles?" Both types of waves possess retarded and advanced components which cancel each other and entangle all masses. Wick rotation (time) is built into the Mobius strips and figure-8 Klein bottles composing (respectively) electromagnetism's photons and gravitation's gravitons. Therefore, all time (the entire past and present and future) is united into one thing just as all space and all mass are united into one thing. If time only passed rectilinearly - from past to present to future - the idea of waves travelling back in time would make no sense at all. But if time is curvilinear - with past, present, and future interconnected - time must be able to move from future to present to past.
(Unity of past/present/future may remove the issue of non-simultaneity – in special relativity – because the timing or sequence of events being different in different frames of reference can only exist if past/present/future are separate. The concepts of cause and effect are no longer separate when all periods of time are united, and everything can happen “at once”. This is similar to watching a DVD – every event on the DVD exists at once since the whole DVD exists but we’re only aware of sights and sounds occurring in each tiny fraction of a second.)
Third, proposing faster-than-light travel (a feature of special relativity is light-speed as the universal speed limit).
The Riemann hypothesis, proposed in 1859 by the German mathematician Georg Friedrich Bernhard Riemann, is fascinating. It seems to fit these ideas on various subjects in physics very well. The Riemann hypothesis doesn’t just apply to the distribution of prime numbers but can also apply to the fundamental structure of the mathematical universe’s space-time. Cosmic maths incorporates
1) topology (the two-dimensional Mobius strip and figure-8 Klein bottle which is immersed [not embedded] in three dimensions),
2) BITS aka electronics’ BInary digiTS, or base 2 maths, which encode the topology,
3) the real and imaginary numbers of Wick rotation (time),
4) vector-tensor-scalar geometry, describing interaction between photons and gravitons, and
5) the Mobius Matrix, combining the topological Mobius and mathematics' Matrix to explain higher dimensions.
How does the Riemann Hypothesis support Faster-Than-Light travel? Answer – Using the axiom that there indeed are infinitely many nontrivial zeros on the critical line (calculations have confirmed the hypothesis to be true to over 13 trillion places), the critical line is identified as the y-axis of Wick rotation (stated above to be the time component of space-time). This suggests the y-axis is literally infinite and that infinity equals zero. In this case, it is zero distance in time and space. Travelling zero distance is done instantly and is therefore faster-than-light travel.
It must be stressed again that I’m not saying the above ideas are either correct or incorrect. I’m merely seeking to show that modifications to special relativity, general relativity, and quantum mechanics are indeed possible!
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Gravitational, electrostatic and Planck’s constant change value at relativistic velocities.
March 4, 2023, By Samuel Lewis Reich, slrcxh53@gmail.com, Tribco Inc.
Abstract:
Proofs that the gravitational. electrostatic constant and Planck's constants change value at relativistic velocities in equations applied to particles with REST mass. When in equations applied to things moving at the speed of light, they are constants even at relativistic velocities.
Givens:
The link at the end is to a PDF file containing original proofs that the axial and gravitational Doppler shifts changes observed time and distance. Others came to that conclusion also.
For objects with a test mass the frequency(f) ratio of the axial Doppler shift is
Ka=f’/f=t/t’=l/l’=[1+(v/c) cos q] implying the that of time (t) and distance (l) =1/[1+(v/c) cos q]; where ‘ is the observed, v is positive for blue shift and negative for red shift. The angle between v and a line of sight to the observer (could be and instrument) is q.
Gravitational and Electrostatic Constants.
The formular for gravitational force is Fg=G (ma/ra)(mb/rb). For the case where the observer is much further than ra or rb away the a and b can be dropped because Doppler shifts for both are the same. The observed masses have a change with velocity of Doppler shift of 1/Kt=1/transverse Doppler shift for objects with a rest mass and 1 for other things. Force is
Energy(E)/time (t).
Therefore: G=(E/t)/(m/r)^2 ; ^=exponent E=mf cc (mf=mass transferred by the force). Since we are just interested in units not values.
G=r^2/(mt)
Because m, t, and r have the same transverse Doppler shift Kt can be ignore or set to one. However m has an axial Doppler shift of one (1). The axial Doppler shift of t and r = 1/Ka.
Therefore the observed G=G’=[r^2/(mt)] Ka/(Ka Ka)= 1/[1+(v/c) cos q].
The result is the gravitational constant varies with and q at relativistic velocities. Since electric charge has a mass and force between electric charges has the same equation, the electro static constant also varies as 1/[1+(v/c) cos q.
Planck’s constant h:
E=hf
h=E/f for light E and f have the same Doppler shifts = Kt Ka and h is a constant.
For things with a rest mass:
But when applied to particles with an a rest mass as does the uncertainty principle E has a Doppler shift = Kt and f =Ka Kt. The result is the Doppler shift of h is h’/h= 1/Ka.
The uncertainty equation (let # be the symbol for uncertainty): h/4Pi = #E#t; therefore
h’/(4 Pi)= #(E Kt) (#t/(Ka Kt))=#E#t (Kt^2)(Ka). Here h is a function of q and v.
Link to a PDF file of proofs that the gravitational and axial Doppler shifts change observed
time and distance like the transverse does:
---------------------------------------------------------------------- https://drive.google.com/file/d/1agua51JKM3nE7L17tmaWuluPiqQ4Ag55/view?usp=share_link
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In energy dispersive X-ray Fluorescence (EDXRF) the continuum "Bremsstrahlung" frequently appears to the right of the spectrum, in its most energetic range. How does this X-rays originated from the source interact with the sample to return to the detector? Could it be used this intensity as a sample density predictor?
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the continuum "Bremsstrahlung" in the high energy part of the EDXRF spectrum is the due to the Compton scatter of the Bremsstrahlung of the primary x-ray beam.
Its strength is proportional to (local) electron density of the sample; and thus for a given atomic number Z, proportional to the mass density of the sample.
Compton scatter imaging relies on this principle; here mainly the spectrum integral is used, but not the spectrum itself.
However there is some calibration necessary for getting absolute density numbers.
Best regards
G.M.
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I am planning to set up xray transmission system for my research work.
Which one is the better resolution for xray sensor:
a. 25 Lp/mm
b. 33 Lp/mm
Which xray sensor is better in image quality:
a. Schik33
b. Polariod
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33 lp/mm will offer high resolution as compared to 25 lp/mm. Depending on your applicattion,, 25lp/mm may suit well when considering the higher quantum noise associated with 33 lp/mm.
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Brother Potamian (Dr Michael O Reilly, 1845-1917) was a Brother of the Christian Schools. He taught physics at Manhattan College (Nex-York). He was spécialized in radiotelegraphy and electricity. He collaborated a little with Lord Kelvin and John Tyndal, but more importantly with Marconi. He studied the X-rays after their discovery by Roentgen and acquired a skill in this area. Did he make real discoveries?
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I'm familiar with Brother Potamian because of his excellent biographical history of electromagnetism, Makers of Electricity: https://archive.org/details/makerselectrici00reigoog
Thanks for the paper, Susan Barber. If any one else has any biographical information on this fascinating scientist and author, please share.
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For example, for X-rays generated from a tungsten target.
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You have to elaborate your question. There are many ways to reach to the dose rates. However, it is important to focus on direct problem.
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What will happen if other metals will be used in this analysis?
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According to Moseley law, higher the atomic number of target material lower will be the characteristic wavelength. The target has to be metallic (conducts electron) and has a high melting point (40 kV at 30 mA generates 1.2kW of heat). This limits the choice of anode materials. Cu gives the shortest wavelength above 1 angstrom and gave reproducible data at low and high angles.
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What can be objectively defined as measurable and auditable standard
1 Question is justifiable and essential Xray chest requests in children less than 3years presenting to Emergency department expressed as a percentage?
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According to the disease condition of the child
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After extracting the Raw file using Powerdll software, the extracted file is usually plotted in Origin. What other route can be used to analyse your XRD result?
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E.O. Achukwu You can improve your results by using XperHighScore Plus and fullproof with the assistance of origin. If you are examining XRD results for the first time, Origin is also an excellent program to use. It's appropriate for novices. Origin is an excellent piece of software for novices.
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I am working on detection of covid19 through Xray images and CT scans images using Deep learning and CNN , now i want to add new feature in my project that after detection of covid 19 it will also detect the age of patient too. please any one help me out ??
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Please answer should be in one sentences
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In addition to all interesting answers, x rays are waves if they are used as part of Maxwell classical equations. They can be quasiparticles (with no mass but they have linear momentum p) if they are used in the second quantization formalism, in such a case there are two subfields: the nonrelativistic quantum optics [1] or the QED, where they both use the creation and destruction operators for photons as quasiparticles.
Let us wait for a specialist in QuanOpt to see if there are differences among the three approaches. The energy for which they are emitted or absorbed is around:
  • 1 MeV (106 eV) for intranuclear transitions.
  • 1KeV (103 eV) for inner electron transitions.
[1] Loudon, R. (2010). The quantum theory of light.
Best Regards.
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I have to summarize model of care for staffing of diagnostic imaging that includes the following modalities: Xray, CT, MRI, interventional radiology, nuclear medicine.
Looking at number of staff required on a shift based on number of inpatients and outpatients
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I have been asked this question at my work quite frequently. I think the general agreement is that it is difficult to overgeneralise - cannot use the answer from one hospital/facility/practice to another. Some places have a very specific type of population/patient and it can be much more tedious than another that reports a lot of "normal" studies - which would be much easier/faster.
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Dear All,
I'd like to share my experience with our manuscript (theoretical concept) reviewing process. Currently, we are studying radiation shielding materials, particularly glass substances. The effect of different oxides and various glass types is under our scope. In literature, almost all researchers are trying to understand the same scope, as well. However, our recent paper submission was reviewed, and the reviewer concluded that the impact of heavy metal oxides has already been known, and no need to evaluate the manuscript for a possible publication. However, our paper did not only have radiation protection but also physical, mechanical, and optical properties.
What I am trying to ask you all is that this is a fair decision within radiation shielding studies? Is it not the correct way to investigate different glass types, as well as various oxide contributions in terms of theoretical radiation shielding parameters?
Thanks in advance for your valuable comments.
With warm regards.
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Also i consider the reviewers just consider the shielding performance, but as new materials, the comprehensive proeprties are needed
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I am trying to find a table of the energy absorption coefficients (or mass energy absorption coefficients, I don't care because I can convert) in silicon dioxide for a variety of photon energies representative of x-rays and gamma rays. I expected this information to be easy to find because ionizing dose is a concern for electronic devices exposed to radiation, but the only tables that I found so far apply to various biological materials and not SiO2. Other types of attenuation coefficients can be found for SiO2 but these are not the same as the energy absorption coefficient.
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You can try the free software MUPLOT which can be found at the following link:
To download, please go to the corresponding page. Let me suggest to compute the mass attenuation coefficients for the compound SiO2.
Kind regards
Jorge
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Now in the electronics industry day by day, we are able to reduce the size of the transisitor. Now presently researchers are working on 10nm or 5nm technology. So in the industry how people will pattern such small features say 10nm or 5nm. which lithography tool(UV, E beam, Xray) will be used in this patterning?
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Dear colleagues,
recently there was a question here on RG about a mysterious high energy shoulder of a gamma peak.The real reason for that is unknown up to now.
One of my ideas is EMI interference with cell phone radiation.
It is well known, that cell phone (handy) radiation affects/irritates sensitive electronic equipment.
A HPGe detector is such a sensitive device.
Does anybody of you have performed tests about that issue; are there any experiences?
Any contributions are welcome...
Thanks in advance and best regards
G.M.
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does the shoulder appear in the total energy peak in the HPGe gamma spectrum of certain samples, there are two probabilities, if the problem in the HPGE detector, adjust it if not it is problem due to the high activity of the sample therefore it is necessary to remove the sample at the level of the detector to eliminate the peak sum phonomene
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I would like to simulate the electrical response of nanowire field effect transistors that exposed to nano-focused hard X-rays using Sentaurus TCAD tool. How can I model the X-ray source?
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In such an electromagnetic radiation nanowire detector device, use Sentaurus ATLAS with a suitable photonic module like Blaze
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When particles get really small (down into the nm range) they are too small to be observed optically and are resonant in the lower xray spectrum. They don't have enough mass to be affected by gravitational objects and have no or little magnetic dipole interaction.
My questions are based on extensive internet searches that come up empty:
Could outer space be filled with nanoparticles of every kind from all matter? Celestial objects are smashing into each other constantly, producing every size particle imaginable. If the nanoparticles were separated by enough distance, xray telescopes, like Chandra wouldn't have the resolution to detect them unless they were massed together. Have there been any space probes that have been designed to test for the presence of individual, stray nanoparticles in outer space?
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We are looking for to find xray card for my organic dyes to specified Miller indices present in XRD powder e.g (c39H44N606)(C18H26N9O6) Best regards and thank you very much for your help and guidance where can i found xray card .
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You can easily get XRD Reference File here,
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Dear members, please recommend the best and easy way for structure refinement from a given single crystal or powder x-rays integration peaks.
mean how to refine fully solved structure from X-rays data.
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Dear Shahab Khan,
For powder diffraction data, I would recommend to use Topas, Gsas II, Fullprof or Jana for refinement and exporting.
Topas is very quick and has some advanced Peak profile features, but it is also not free.
If you are new to powder diffraction, you might want to look at Jana and Gsas II as they are free and offer an excellent cookbook and tutorials to get you started. The value of this for the self-learner cannot be overstated. Particularly Gsas offers a convenient way to export your results to a cif-file.
For single crystal diffraction data you are likely looking at refining that with the free shelx-package, possibly with some other convenience software such as shelxle. Olex is another option, possibly more popular nowadays. Those packages all offer functionality to export your results to a cif file.
After you have your cif, you will want to check it for its‘ viability through Checkcif (available online).
Overall the process is quite involved, it is probably best if you can find an expert at your institute to walk you through it.
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Dear All,
The search for alternative radiation shielding glass materials is very popular, nowadays. The literature has a variety of investigations in terms of experimental, theoretical, and simulation. At this point, what will be the next for radiation shielding glass? In a commercial manner, there are some products having PbO content for the intended photon energy level, however, is it possible to produce commercial novel lead-free glass compositions in the near future? What are your opinions?
Best regards.
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From a commercial point of view, a new solution is only viable if consistent. So, even with up-and-coming dense materials already available, if they demand a relatively short replacement time due to accelerated aging, the solution is not ideal. Pb doped glasses shielding rest for a lifetime; Dense materials will compete if the lifespan achieves similarities in protection and durability.
Best regards
WNM
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Dear All,
Is it possible to talk about radiation fatigue in shielding glass? I mean, what is the number of cycles that the shielding glass gets exposed until its effectiveness diminishes? Surely, the irradiation source, as well as the glass density, affect the usage cycle, however, I'd like to learn about the number of cycles in a shielding glass. I hope that I have been considering the correct way for understanding the concept.
Thanks in advance.
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The statement by Gerhard Martens is not contradicted, and the statement by Nobuyuki Hamada is supported (with the caveat that CeO2 is added to stabilize the color of the radiation shielding and radiation-resistant optical glasses) in the following book.
[1] Heinz G. Pfaender, (revised and expanded by) Hubert Schroeder; Schott Guide to Glass; Van Nostrand Reinhold Company; 1983; p. 146.
Regards,
Tom Cuff
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My experiment demand x-ray CMT imaging. I need to place my samples over a substrate that should be x-transparent. Can anyone please any suitable materials (rather than foam) that is x-ray transparent?
Thank you in anticipation.
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Dear Pradip Singha , any stiff material consisting of low atomic number elements are suitable.
Examples are PMMA or polycarbonate.
Patient tables for Xray CT are built as sandwich of carbon fibers tissues (plate) -foam-carbon fiber tissue.
For small weight sample a thin carbon fiber plate is sufficient.
You may have seen them already.
In the attached linke there are some picture of such plates:
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I try to crystallize miniprotein by hanging drop method. Here is a drop picture, where the precipitant is 1,4 Dioxane (35%). I think it looks like crystals but they does not have sharp edges and look like walnuts with round shape. Could you suggest me how can I optimize conditions and get more sharp and good crystals?
I think it is because of fast growth probably? Should I try seeding from these crystals?
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Dear Svetlana Korban many thanks for your interesting technical question. As an inorganic chemist I'm not an expert in protein crystallization, but I can suggest to you some potentially useful references which might help you answering your question. Please have a look e.g. at the following articles entitled
1. Introduction to protein crystallization
This article is freely available as public full text on ResearchGate.
2. X-ray structure analysis of a designed oligomeric miniprotein reveals a discrete quaternary architecture
(see attached pdf file)
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Is the signal too noisy? Energy too low? Are all TEM EDX detectors above the sample? There are detectors of electrons below but no EDX. I just wonder why this is.
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in addtion to what Gerhard Martens has already mentioned, I think that you'll get a much higher background due to Bremsstrahlung radiation in foreward direction. So smaller peaks are added on a larger background ... Best regards, Dirk
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When studying EXAFS and XPS, I often see that "X-rays bounce electrons from atoms".
Where will the electrons that are blown off the atoms by X-rays eventually go?
In the case of EXAFS, I think that "electrons are blown off from the atom, but they remain in the substance, and the electrons eventually return to the original atom." Is this the correct answer?
In the case of XPS, how should it be interpreted?
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Dear Jun Kawai,
Thank you for your valuable materials. I got a better understanding of X-ray absorption in the EXAFS region. Read the material and lead to further understanding.
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Generalization of COVID-19 models is a very serious challenge. I'm trying to find a model (ct scans or x-rays) that was trained and evaluated on multiple datasets. It would be particular interesting to look at the model that was evaluated on an entirely different dataset (not in the training set.
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So what exactly are you looking for? A set of CT images with known outcomes? CT data that has been analyzed by another AI algorithm? Answer without using the word Model, since that term appears to be causing most of the confusion.
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gamma radiators or electron beam use on large commercial in your country 
what is your information about same use in others country near your
Have you any statistical like map or published data for trade in irradiated food 
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yes ,we have one for commecial scale of food products and medical products for exportation only for first but the second for local and exportation
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Hello, I need to find Covid-19 chest x-ray images with the details about how many days passed from the onset of symptoms till the x-ray was taken. Does anyone know where I can find it?
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This is also a covid19-radiography public dataset
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Hello,
I wish to calculate inter and intra rater agreement between 2 observers who are gradings Xrays for degree of bony fusion into 6 grades. In all there are 1750 xrays. Which statistical test would be most appropriate for the same? Is there an excel sheet template available for making this calculation for 1750 xrays. If not excel is there any online platform for this calculation apart from SPSS??
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Key phrase here is "agreement between". Cohen's Kappa method is a strong suggestion for comparing the categorical decision scoring of two comparable "judges". Available in the SPSS Analyze-Descriptive Statistics-Crosstabs-Statistics-Kappa menu.
Cohen's Kappa gives you the strength of proportion of agreement (outside of chance agreement) between two independent observers (judges) as well as the probability that this agreement is statistically significant compared to zero (0). This is "Inter-rater" reliability NOT "Intra-rater" reliability (oh what a difference one little letter makes!).
On the other hand for the key logic phrase "agreement among" (aka "Intra-rater" reliability). Use the old reliable Cronbach's Alpha test. SPSS Analyze-Scale-Reliability Analysis-Model Alpha.
Understand that all models have specific mathematical assumptions, and that the data being tested must meet or exceed those assumptions in order for the test results to be considered mathematically valid and publishable in peer reviewed scientific journals.
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Hello,
I am trying to calculate the radiation exposure of an x-ray to determine the safety of it in a medical circumstance.
I've I'm using an x-ray at 1 KeV/sec going into water (1g/cm3), what is the exposure in Sierverts?
If you wouldn't mind elaborating on your calculations that would be great.
Thanks!
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I have experimentally observed that different materials or chemical compounds have significantly different Compton Backscattering efficiencies as a function of the incident X-ray or gamma photon energy. This spectra effect can be used to classify materials into broad types. However what I lack is a sound theoretical basis for why this is the case? I suspect the effect is due to the size of the molecular bonds, with weaker bonds producing an effect where lower energy X-rays are more efficiently scattered than is the case by stronger more localised molecular bonds.
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nice view onto details of Compton scattering.
But what is your answer to the question above?
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In energy dispersive spectroscopy how every element is directly related it's corresponding k l m n series irrespective of their unique atomic structure. It is directly given eds spectra no doubt but it will be interesting to know the element and series relationship irrespective of x rays are given out from shell with ejection of electrons at different levels. Is their any relationship between outer electronic configuration and different series
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So, just to recapitulate: your question is why the EDS/EDX peaks are as characteristic and well-localized as they are and why they don't shift due to the outer binding situation?
If that is the question, you have to be aware that you are working with keV-sized incident electron and outgoing photon energies. In XPS (i.e. the reverse effect) the outer shells lead to binding energy shifts in the single eV magnitude (=3 orders of magnitude smaller). The resolution of EDS is much lower than that, see
So, there is an influence, but it's so small you can't resolve it. If your sample allows it, XPS is a good option for that.
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Hello,
I am new to the study of electromagnetic interactions with mediums, and I am trying to calculate the depth an x-ray would penetrate water.
From my findings, I understand that I would need to use the mass attenuation coefficient of water at a certain wavelength (λ) of x-rays, and from there I would be able to find the depth achieved by the x-ray.
Does anyone know how to put this all together in a single equation, i.e. where given the eV or wavelength (λ) of the x-ray, how deep will it penetrate into water?
Thanks!
Antoine
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the penetration of x-rays obeys the Lambert-Beer law:
I=Io*exp(-µ*d).
Here Io is the primary x-ray intensity and I the intensity at depth d. µ is the linear attenuation coefficient and depends on the photon energy E ( or wave length λ) : µ=µ(E) .
According to the exponential law the penetration depth dmean is defined as:
dmean = 1/µ
For calculating the µ you have to go via the mass attenuation coefficient µ/rho (with rho being the density).
The mass attenuation µ/rho is provided by:
Please enter the necessary data and press the submit button.
You may enter special photon energy values but you also may skip the standard energy grid .
From the calculated table please take the 'Total Attenuation' column 'with coherent scatter'.
Fortunately the density of water is 1g/cm³. So the numerical value of the data will not change but the unit will change into 1/cm when multiplying the µ/rho value (in cm²/g) by 1g/cm³.
Please play around wiht this nice page.
For any question please do not hesitate to contact me here.
Good luck
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In an upcoming experiment I would like to embed some powder in a media, and polish it to low surface roughness. Even though I have used epoxy-resin embedded samples before on a synchrotron (and with hard X-rays) I was now advised to look for other possibly "more resistant" embedding media. Does anyone have experience with long exposition times of epoxy in a hard x-ray beam?
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if having enough sample material pressing the powder to a rectangular or cylindrical pellet could solve your issue.
You will get a flat surface according to the surface of your pressing tool.
Part of the compression mould can be used as sample support.
So you can easily use your sample in an horizontal directed beam without removing the pellet out of the mould.
A further advantage of this method is to avoid any additional material in your sample, which will lead to signal reduction due to x-ray attenuation (Please note that your are below 5keV).
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In designing the Xray machine, we always want a monochromatic Kalpha radiation of X-ray source. For this purpose we generally put a filter to reduce the k beta radiation but still we get some k beta intensity.
My question is If we design a filter material whose K absorption edge lie exactly at K beta radiation peak of targeted source then maximum possible absorption take place. So is there any problem to design this material or it will affect the X-ray performance.
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Spectral contamination in 'old' tubes is observed via the W L-alpha doublet, caused by W atoms arising from the hot tube filament.
Here we accidently have the quite ideal situation where in the energy spectrum the Ni K-edge position ( 8,333keV) is just in front of the W L-alpha lines (8,335keV and 8,398keV). In case of a Cu based tube Ni is used to reduce the Cu k-beta line. So this filter fortunately will reduce the W L-alpha line(s) too.
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I have followed the advice on this site, Penn State research papers and numerous www.ncbi.nim.nih.gov articles. A man was diagnosed with osteoarthritis of the knee due to a severe motocross accident. I've attached his x-rays from before and after the plates were finally removed from his leg which was one year after his crash. I need advice. Does the second set of x-rays reveal a total healing, or are we just seeing the effects of numerous chondroprotective supplements which were given to him in the hopes of opening the space in his knee? I ask because it seems to soon to experience this level of healing. I've also attached the patient's supplement list with dosages and dates. Please understand that the supplement list was created for my benefit and not necessarily to be read by others. By this, I mean I was only attempting to keep my research straight.
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On A/P radiograph measurements between the medial femoral condyle and the midpoint from medial tibial spine to medial border of the medial tibial condyle can provide Joint space measurements. Using the Baumgaertner score can help to determine clinical results with radiographs. (Bae et al J Korean Orthop Assoc 2008). However, if one is looking to determine cartilage healing, MRI, biopsy (histological assessment), arthroscopy, immunohistochemical staing and Western blotting test for type II collagen after microfracture can be used.
(Bae et al, J Arthroscop & Rel Surg 2006; Systematic Analysis microfracture technique, Mithoefer et al Amer J Sport Med, 2009). I hope this helps.
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Scattering characteristics of both are expected to be different by two techniques i.e. X rays and neutrons
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The xray scattering cross section is essentially proportional to Z^2. Therefore the signal will be largely dominated by scattering from heavy atoms. In contrast the neutron scattering cross section varies from element to element. You can get an overview of scattering cross sections for thermal neutron energies at https://www.nist.gov/ncnr/planning-your-experiment/sld-periodic-table .
Since xrays scatter strongly from electrons it carries information about a scattering volume at the surface which is determined by the energy-dependent penetration depth. Neutrons interact weakly with matter and unless your sample contains some strongly absorbing element like cadmium or boron will probe the bulk of the sample. Also xrays can be focused onto a tiny scattering volume and can often give a lot of information from tiny samples. For neutrons usually large samples are needed to get a decent signal.
These are the most obvious general differences. Depending on your specific project other qualities can become relevant. What are you planning to do?
A comprehensive source of information on xray, electron and neutron scattering is volume C of the international tables on crystallography. (https://it.iucr.org/C/)
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How can I generate powder XRD pattern by simulating Single crystal xray data ?
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Dear Saurodeep
If you didn’t solve it yet, I recommend you to use VESTA software. It is a free software.
If you want the steps to generate the XRD pattern, it is as follow:
Utilities ® Powder diffraction pattern ® then click on conditions ®
you can change the No “FE” to single if you want, of course it depends on your approach.
Then click on “calculate”
After the software finish its calculation, click on “plot”, to see its XRD pattern.
If you want to look the value of different items at each peak, you can click on “reflection” then you will get a table and you can get important items like: hkl, M(multiplicity) and others at the respective degree (2 theta).
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Does anybody know any X-Rays vertebra image segmentation dataset with their Ground-truth? I need labelled dataset with both normal and fractured bone images.
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We are trying to focus ultra-short (femtosecond) x-rays from a point source (laser plasma x-ray source) on a sample. There are several options available. Among them there are Poly-capillary optics, Crystal optics and Multilayer optics are main contenders.
Multilayter optics is best among them due to its high reflectivity and low temporal stretch of the x-rays. In multilayer optics, Montel optics (two multilayer curved mirrors mounted at right angle) and Single bounce mirror (toroidal bend multilayer mirrors) are two options.
Kindly suggest which of these two (Montel optics and Single bounce mirror) is better and easy to handle.
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We are currently using toroidal mirrors for the purpose of registration of HHG spectra. They are definitely easier to operate and align.
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X rays tubes are Highly evacuated
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Usually the leftover gas in the tube only provokes Lilienfeld-radiation, which corresponds to a loss of energy in the bremsstrahlung [close to the anode]. At high energies (10-100 kV) sputtering is a much bigger problem, especially with static anodes, as well as self-absorption of emitted photons close to the anode. The pressure of the tube corresponds to its lifetime, but only in theory. In reality there is no big difference.
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X Ray radiations might be sequentionally accumulating in the walls of x ray tubes with each production of x rays
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In addition to Nikolay's answer,
degradation of the anode/target surface is another point with respect to tube ageing, especially for high power tubes.
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Hi Fellow Research Folks,
I have been looking for a transgenic mouse model to track the temporal association of two known protein interaction. I came across a paper "Noninvasive imaging of protein–protein interactions in living animals' by Luker et al. 2002. But I was wondering anyone has worked on a similar scenario and can shed some more light about any existing tool to look at such interactions without sacrificing the mice(Imaging modalities like Xray, MRI,CT or PET etc).
Thanks a lot!!
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Nisha Kuzhuppilly Ramakrishnan : Thanks a lot. I was leaning towards that idea as well but thanks for the heads-up!!
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In radiation, the transfer of heat from one body to another body requires no transmitting medium. There are several types of electromagnetic radiations such as cosmic rays, gamma rays, x- rays, ultraviolet rays, infrared rays, etc. However, in calculation of radiation heat transfer between two bodies only thermal radiation is considered. What could be the reason? and what would be the limitations?
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Hi Pisipaty,
certainly, energy can be transferred between bodies by em radiation of any frequency. Which part of the spectrum is mainly involved depends on the nature of the bodies. If they are not devices specifically designed to emit radiation then - in the temperature range we usually deal with, say below 3000° K - nearly all of the energy radiated by them is located in the infrared domain, i. e. it's thermal radiation (see Plank's black-body radiation law).
Of course, this is not true if we deal with devices like microwave ovens or mobile phones. If you want to estimate the increase of temperature in your body caused by a mobile phone you have to take the frequency band used for transmission into account.
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or an equivalent device that can be used the same as for instance LDR but this one varies with difference in amount of X-radiation incident on it
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Mohammad is right.
Creation of charge carriers in the case of x-rays is utilized in the x-ray semiconductor dectectors such as HPGe ; Si(Li) or CZT
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I am studying the performance of deep learning (DL) models toward abnormality detection in chest X-rays. Due to sparsity of data, I augmented the data using different augmentation strategies including: a) traditional augmentation methods including Gaussian smoothing, unsharp masking, and minimum filtering; and b) Generative Adversarial Networks. Contrary to the existing literature, I find that the DL models showed promising results with traditional augmentation methods (that i have mentioned herewith) than with GAN-generated synthetic images. What brings this performance difference?
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We have studied the effect of utilizing synthetic images produced by GAN for data augmentation purposes. The effect is studied for object detection and segmentation tasks. The paper can be accessed by the link below:
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I am trying to plot a radiation dose response curve using graphpad prism. I an using a nonlinear regression (curve fit)> linear quadratic survival (Y is percentage). X is radiation dose in Grays (0, 1, 5, 10, 15, 20). The input equation is Y= 100*exp(-1*(A*X+B*X^2)). Rule for initial values of A = 1.0 amd B= 0.1. No constraints. No weighting. The best fit values for A obtained following analysis = 0.1687 and that of B= -0.005797 and A/B ratio = -29.10. This does not make any sense. Could some one help?
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How did Dr Sasidharan S Lucky determine the survival of cancer organoids? LQ is a model for cellular clonogenic inactivation. Target theory was proposed in the 1940s based on experiments in bacteria, but the LQ model has broadly been used for clonogenic survival curve since mid-1970s ( )
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The working teems in the x-ray unite in veterinary branch exposed for daily x-ray dosage ,and must of the working staff afraid from the x-rays power for its disadvantage properties.even the students have the same felling .so we suffering from changing these information ,I know that the over expose to this power with out protection methods or in case of immunity depression is not safe and dangers .
I hope to know how to calculate the real x-ray dosage for both the human being and patient ( x-ray permissible dosage).
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It's well known that our environment itself has minimum level of radiation. Added to that radiologist are supposed to work in the same environment. Though 20mSv/a is advisable by US govt, it's advisable to carry Digital Pocket Dosimeter with them.
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These are Highly evacuated thick glass tubes
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How to measure it
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Simple access to tabulated values are available via the website of the Center of Xray Optics: http://henke.lbl.gov/optical_constants/
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Anyone, please refer me to some pixel level annotated medical image data-sets. I have proposed a technique to annotate the disease at pixel level using weak labels e.g. image level labels. Now I have to evaluate that technique using some metric say Intersection over Union in my case. So please refer me to some medical imaging data-sets in which there are some images available with some annotated bounding box or pixel level annotation. The data-set shouldn't be too complex. If some of the images are annotated at the pixel level and remaining are at image level it will be appreciated too. Anyone available with some pixel level chest X-rays for TB detection is much appreciated.
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Hi,
you can maybe benchmark your method on one of the following challenge:
See you,
Cyril
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Hi there scientist!
I'm try to enstablish what kind of radiation are emitted from a 200 keV Si ion stopped in a Si target for ionic implantation.
I'm expecting to have just fluorescence X rays, but I'd like to know if there's a way to calculate the X rays maximum energy and if there are any other possible radiations emitted.
Thanks for your help!
Oliviero
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The primray ions in such energy will NOT result in any radiative X-ray. However, You will see characteristic X-ray resulting from relaxation of exited and ionized atoms. Also, the secondary electrons might undergo Bremsstrahlung interaction and produce contentious X-ray spectrum depending on how much energy they pick from the primary ions.
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Have a nice day everyone,
How does a Si/Ge photon detector discern energy from intensity, when both the energy of a photon and intensity of photons would proportionally contribute to the signal?
(The following is optional to read)
The working principles of energy-dispersive x-ray spectroscopy (EDXS) include the use of a semiconductor detector. The semiconductor is induced electron-hole pairs upon incident ionizing radiation. The number of induced electron pairs is proportional to the energy of the incident photon.
Ehv = N Eeh
where Ehv is the energy of an incident photon; Eeh is the electron-hole pair formation energy and N is the number of induced electron-hole pairs.
It is said that the detector use this proportionality to discern the energy of incident x-rays.
However, the number of induced electron-hole pairs is also proportional to the incident photon intensity/flux/number. Then we should also have
NhvEhv = Nt Eeh (I added this one. It was not written in the textbook.)
where Nhv is the incident photon number and Nt is the total electron-hole pair number induced: Nt = Nhv N
The question is: How does a semiconductor detector discern photon energy from photon intensity, if two of them both contribute to the number of electron-hole pair induced?
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adding to Erik's answer. The electronics of the detector must be designed to collect the electrons from a single photon. The detector and electronic system has a rate limit on collecting and forming the electron pulse. The photon rate striking the detector must be lower than the rate limit of the detector and electronics. The higher the photon rate the more pulse pile up and summing. A too high photon rate will render the system useless for both energy and intensity.
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Have a nice day everyone,
The working principles of energy-dispersive x-ray spectroscopy (EDXS) include the use of a semiconductor detector. The semiconductor is induced electron-hole pairs upon incident ionizing radiation. The number of induced electron pairs is proportional to the energy of the incident photon.
Ehv = N Eeh
where Ehv is the energy of an incident photon; Eeh is the electron-hole pair formation energy and N is the number of induced electron-hole pairs.
It is said that the detector use this proportionality to discern the energy of incident x-rays.
However, the number of induced electron-hole pairs is also proportional to the incident photon intensity/flux/number. Then we should also have
NhvEhv = Nt Eeh (I added this one. It was not written in the textbook.)
where Nhv is the incident photon number and Nt is the total electron-hole pair number induced: Nt = Nhv N
The question is: How does a semiconductor detector discern photon energy from photon intensity, if two of them both contribute to the number of electron-hole pair induced?
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Dear Yen-Chun Chen,
your issue is a matter of the time scale of the incoming photons.
Imagine that you have got ‚only‘ 1 photon for example in 1 sec.
Here the detector has enough time to collect the charges and to provide a voltage signal in the form of a voltage peak. The shaping time of the detector’s circuitry governs the width of the peak. Its height is proportional to your number N = Ehv / Eeh given above by you.
So far all things are ok.
But now the intensity comes into play.
Having increasing photon intensity falling onto the detector the time distance between two successive photons more and more decreases down to that point when two photons interact with the detector within the shaping time of the detector.
In the worst case now the electric charges arising from absorption of two photon are collected and the voltage peak height will be proportional to the sum N1+N2 of the two charge clouds. This effect is called ‚pile-up‘. However due to the statistical distribution of the photon time distances in the x-ray beam the fraction of voltage peaks suffering from pile-up is quite small. But for increasing intensity the amount of pile-up events increases nonlinearily.
For sufficient ‚high‘ photon intensity even three-photon pile-up events may show up.
In a peaky x-ray spectrum (e. g. from x-ray fluorescence or gammas from radio nuclides) pile-up shows up when sum peaks in addition to XRF or gamma peaks are popping up. Sum peaks have got the an energy position which is equal to the sum of the photon energies of the involved photons (double or even triple photon coincidence).
In countinous x-ray spectra arising from an x-ray tube, pile-up artifacts are seen as an up-coming photon background beyond the kV limit of the x-ray spectrum. In the ideal case(i.e. no pile up) only a very few counts are showing up from surrounding radio-activity and radiation from space.
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Ruby (Al2O3 doped with Cr3+ ions), when exposed to ionizing radiation (for e.g. X-rays), emits luminescence. What is the mechanism that causes this 'Radio-luminescence? Does Cr3+ accept electrons or give up?
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@Raju: It may happen that we use such conversion for understanding but possibly no such experimental evidences are available in many cases. Even if conversion is there, it may be well below detection limit and negligible. See sizes of different states, they may find difficult to adjust in lattice etc.In CaSO4:Dy we assume Reduction as per Nambi Model, but experimental evidence is not there. There is no change in colour evan after huge irradiation for CaSO4:Dy, if reduction holds, colour should change. You may contact Dr. B. C. Bhatt, who is also on ResearchGate and has done pioneering work in these fields. I am also sharing the question with him.
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The attached pictures are pole figures of 0 and 90 degrees azymuthal angles. MAUD program is used with texture (E-WIMV). The symmetry used was orthorhombic symmetry because my sample is orthorombic. In figure with 0 azymuthal angle, it looks like fiber. However, at 90 azymuthal angle the amximum mrd intensity of 002 is in center but 020 and 200 on edges. Is it means that 002 is oriented parallel and 020, 200 oriented to perpendicular to x-rays? or any other meaning?
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Dear Gert Nolze,
Thank you for your answer.
I meant that the phase of my sample is orthorombic that is why I choose generate symmetry as orthorombic in MAUD program. Should I used symmetry as none and refine again?
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Dear Valeria,
Your project is entirele medical one!
I have some understanding in orbital mechanics and in x-rays, electron and neutron radiation transfer.
If I can help you, please, write.
Sergey Meshcheryakov
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no thanks
but maybe you should contact that Valeria guy directly
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Dear Researchers
XRD measurements were carried out using Bruker D8 Advance X-ray diffractometer. The x-rays were produced using a sealed tube and the wavelength of x-ray was 0.154 nm (Cu K-alpha). The x-rays were detected using a fast counting detector based on Silicon strip technology (Bruker LynxEye dtector).
I obtained the result in UXD. file format. Please help me regarding any software to open it.
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Open with notepade copy all to origin software and click plote
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We are doing a study on prevalence of osteoarthritis, and while in advanced step of the study we'll be diagnosing through physical assessment and X-rays; I want to know if I can make a primary assumption based on WOMAC and SF-36 results.
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hello, my name es Sergio Abate. Since 2013 I have pain in all my joints. Y dont have evidences for lupus, or another pathology according to repeatedlaboratory studies. Only have elevated erythrosedimentation and reactive protein C . Nuclear magnetic resonance could not confirm ankylosing spondylitis or another kind of rheumatic pathology, but as X-rays and tendon ultrasound Y have damage to all joints, tendons and synovial bags. I consumed sulfasalazine, prednisolone, amitriptyline, duloxetine, etoricoxib, however my pains persist, and every time I have more damage to my joints. Despite the distance can I be a useful case for your project? . I've been looking for medical answers for years and I do not get them in my country
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The 3D Bragg coherent x-ray diffractive imaging involves the measurement of rocking curve scans in the vicinity of Bragg reflections. The counting time at 3rd generation synchrontron is on the order of minutes for 200 nm objects. However, in a lot of cases the particles start to rotate under the beam.
Are there any known good ways to fixate the particles under high fluxes of x-rays (1e11 ph/µm) ?
Thanks!
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intense and completely coherent X-ray pulses with repetition rates of 10–100 Hz and duration of tens of femtoseconds have been available at X-ray free electron laser (XFEL) facilities.
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I'm a chemist, not a biologist or paleontologist. But I'm very interested in fossils.
I bought a fossil from the early Devonian (Emsian) of Bundenbach, Germany (Hunsrück slate), which I cannot assign. At first I thought of Porifera, but I know only glass sponges like Protospongia from Bundenbach and they look different (at least for me). The x-rays show structures that I cannot interpret; but I would not expect such structures in sponges. Any idea what this is? Somebody help me, please!
Thanks
Thomas
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Thomas:
Discernable features at first glance rule out organic nature of such structures. Also have a look at this link:
Best
Syed
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In an XRD experiment, the incident X-ray beam (usually Cu K-alpha, Mo K-alpha and etc.) falls on a single crystal and, while a small portion of it gets diffracted, forming the spot pattern, most of it gets absorbed by the sample, leading to atomic transitions. These transitions will generate characteristic x-rays from the sample atoms, leaving the sample in almost all directions. As x-rays can penetrate tens of microns into the sample (depending on the elements of the sample, of course) then would it be possible that these characteristic x-rays originating from the elements of the sample be diffracted by the atomic planes of the remaining sample volume and contribute to the diffraction pattern? I would think that the phases of these x-rays will vary but this also applies to the x-rays coming from the tube (keeping in mind that the ideal explanation of diffraction considers the incident beam to consist of the same phase incident plane waves). Perhaps such an effect is possible but too small and is negligible, still I wanted to put the question out there for comments. Thanks.
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Dear Dr. Lanza,
You are indeed right: In a XRD experiment in transmission mode, the brightest spot on the pattern is the directly transmitted beam. There might be also inelastically scattered X-rays contributing to that beam but still, quite a number of photons contribute to that central beam. Out of the rest of the photons, most will be absorbed by atomic transitions and only a small portion will elastically scatter and form diffracted beams. I should have said probably "out of those x-rays that interact with the sample". Thanks for your response.
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i want to know the exact cause why along certain prefferred directions the X Rays are highly diffracted.
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Different atomic planes have different atomic densities, hence, density of scatterers (add on top of that the different form factors of atoms on these planes if your sample is a compound). Intensity is proportional to the number of scatterers per unit area of a given atomic plane and therefore the peak intensities in an XRD experiment will vary. Usually, with increasing plane indices (higher angles in the pattern), the intensity of the peak goes down. There is also the form factor, i. e., how an atom scatters an incident radiation (the "f" in the structure factor formula). You can start looking into these as a starting point.
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I need to find some studies on radiographers prescribing ED x-rays (as like what is being done by triage nurses in the ED currently) but I just can't find any studies done on the effectiveness/suitability of having radiographers requesting x-rays. Which is odd considering that I'm pretty sure radiographers are capable of doing so. Anyone knows of any studies done on this? I've searched everywhere! (I need at least 3)
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have you look for this studies in some international pages ?, until now i dont now any studies about it.
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Just wondering if anybody has ever done this. I would suppose the oligos could suffer, since they´ll be exposed to ionizing radiation for a brief period... but i´m not quite sure if enough to destroy them.
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Unique Response of Double-Stranded Oligonucleotides Containing a Single 8-Oxo-7,8-Dihydroguanine to Gamma Rays in the Frozen Aqueous State at 77 K
may be useful
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Usually the chemistry (Elemental composition) by Rietveld results is not correlating with Chemical assays (XRF or Whole Rock Analysis). When I refine my diffractogram, using scale refining, i'm matching  more or less the Rietveld  chemistry, however to hold the visual match and good GOF I refine (constrained) the occupancies. Is it right?  
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Dear Eduardo,
I have downloaded your *.PRO file and I have opened and run it as I received. Several points to take into account:
-You have included 16 different phases. Most of them have a wt% below 1%.
-I have serious doubts about the presence of some of these phases as Anhydrite (0.1%), calcite (0.27%), chalcopyrite (0.38%), etc. because there aren't isolated peaks that can demostrate the presence of such phases. 
- You are refining the sites occupancies of covellite (1.72 wt%). I think that try to refine such occupancies in a minor phase have a risk: you can get unreliable values.
- If you see the error associated to each refined parameter (Fit/Calculate Errors) you would have a good idea what you really can refine. The errors associated to the site occupancies are huge indicating you that you cannot do it. 
- You can introduce as many phases as you want and also refine as many parameters as you desire and TOPAS will always allow you. Also you will see that the refinement is always improved when you increase both the phases ans the refined parameters but then you can get unreliable results.
- I recommend you to introduce only the phases that you are sure about their presence and with such a high number of phases involved you cannot refine the sites occupancies. Also remember that the error associated with the wt% of minor phases is really high, whatever is the Rwp value.
Regards
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I want to use Monte Carlo program in order to determine the mass attenuation coefficient and attenuation cross-section of human tissue, such as the liver, kidney, thyroid, breast and spleen for different ages and from both male and female, in photon energy range of 1 keV to 100keV
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you may use
GEANT4 Application for Tomographic Emission (GATE) on GATE script
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Is it true that the compounds which are UV sensitive should be sensitive to x-rays or gamma rays as well because the energy of x-rays or gamma rays is much higher than ultraviolet rays?  If it is not so then what could be it's probable cause?   
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Ulf,
in priniciple you are right for the first stage of x-ray interaction (ionizing core shells). But at the following stages of interaction a huge number of secondary electrons will come up from a) emitted photo-electrons, b) Auger elctrons and c) recoiled electron from x-ray Compton scatter processes.
These electrons slow down due to multiple scattering processes (& increasing the number of low energy electrons) down to energies which are able to break bonds.
So x-rays themselves do not break bonds but the secondary electrons will perform that task.
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suggestion required for survey meter.suggest model of survey meter as it will going to be used in radiology (CT , X-ray , Nuclear medicine). .
Thanks
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You may also consider the FLUKE 451P. I have never tested for nuclear medicine purpose, but it is a very reliable and precise tool for monitoring a wide spectrum of X ray, up to rates very close to ground level.
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Please, how do I convert intensity to counts in a NaI detector? For example, If I calculated Intensity of 6mR/hr at 1m, and I need to use the NaI detector to measure the same sample at 1m, the detector returns the reading as counts per minute. Please, how do I relate this to intensity? Convert from counts to the intensity and vice versa?
Can anyone help with technical information on the Co-60 calibration for a gamma spectrometer? (NaI detector)
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This is simple calibration. Divide 6 mR/h by cpm. You are calibrated for that radionuclide at that particular geometry.
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For whole body monitoring thermo luminescence  TL, OSL Film RPL etc are used at chest level or so. Of  which material phosphor your dosimeter is made and what is frequency of use? 
What does it measure Hp(x)?
What type of radiations it can measure other than photons?
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In Romania  the Regulatory Body authorizes the systems of individual dosimetry and appoints the individual dosimetric services approved in compliance with the national regulations. The systems of dosimetry are used with the purpose of evaluating the individual penetrating dose equivalent, H(p)(10) and the individual superficial dose equivalent, H(p)(0,07).
The following types of dosimetric systems may be used with the purpose of the individual monitoring provided that they meet the requirements of these norms:
a) systems of dosimetry with film;
b) thermoluminiscent systems of dosimetry
c) electronic digital systems of dosimetry
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I need to perform Monte Carlo simulations of a imaging device (dental) with static anode x-ray tube.  Can you provide me one or point out a reference/paper/article? Thanks in advance!
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I'm not sure, if someone can provide measured data as gamma (photon) spectroscopy for such X-ray tubes is hard to perform. Scintillator-based detectors mostly have a too rough energy resolution for this purpose. Semiconductor-based detectors are mostly too sensitive resulting in dead time problems. One can increase the distance to the X-ray tube or use collimation to decrease the photon flux photon, but then you will loose low energy photons which would otherwise contribute to your spectrum. In addition, low energy photons are also absorbed inside the cover of the detector (stainless steel cap for cooling).
But maybe you are lucky and someone solved these problems :-)
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i use MCNPX  code for calculate the neutron and photon dose in BNCT but for GdNCT we have auger and conversion electron and i don't know how can i calculate electron dose.
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