RE: Misconduct

[Julian Richard Tolchard]

That is impressive, but I'm sorry to say that I have seen worse. EM images 
though, not diffraction patterns.


From: rietveld_l-requ...@ill.fr  On Behalf Of Le 
Bail Armel
Sent: fredag 12. januar 2024 12:57
To: Rietveld_L 
Subject: Misconduct


Hi,

A good candidate for the "worst Rietveld refinement of the year" award :

https://pubpeer.com/publications/12069A6AD9D5D34F26031F34705D06

Even the difference pattern is totally fabricated.

Best

Armel
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RE: recommended questions to XRD supplier.

[Julian Richard Tolchard]

My personal recommendations from instrument purchasing are:


  1.  Ask them for a full list of accessories available and a price list. Often 
you just don’t realise what useful accessories they sometimes have available.
  2.  Software licences: Buying a new instrument is a good time to get them 
bundled cheap. Offline networked licenses for users are invaluable in my opinion
  3.  Sample holders, prep stations, peripherals: As for software, they cost a 
lot less when bought with an instrument
  4.  Consumables: Find out what is actually consumable, and what it costs to 
replace. Maybe have a spare tube etc. in the purchase if relevant
  5.  User training: Again, see what you can get bundled in the purchase.

As mentioned by others, get samples measured. Try to send samples relevant to 
what you do, but I would personally also throw in some cobalt or iron 
containing samples to check out how good their fluorescence suppression is.


-jools



From: rietveld_l-requ...@ill.fr  On Behalf Of Shay 
Tirosh
Sent: onsdag 14. juni 2023 08:50
To: rietveld_l@ill.fr
Subject: recommended questions to XRD supplier.

Dear Rietvelds,
We are currently exploring the possibility of acquiring a new benchtop XRD 
instrument, specifically the Benchtop XRD from Malvern-Pananalytical. We have 
scheduled a Zoom meeting with the supplier to discuss this further. Before the 
meeting takes place, I would like to prepare by gathering relevant information.
Could you please provide some recommended questions that we can ask the 
supplier? We aim to gain a comprehensive understanding of the instrument and 
compare its performance to other options available.
Feel free to suggest and comment.
Thank you for your assistance.
Best regards,
Shay

--
Dr. Shay Tirosh
Materials Scientist.
With focusing on Photovoltaics, Electrochemistry, Thin film coatings, and 
nanotechnology.


Mobile: +972-(0)54-8834533
Email: stiro...@gmail.com

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RE: Hyper-Lorentzian effect on quantitative analysis

[Julian Richard Tolchard]

Thinking a little outside of the crystallographic aspects, do you have element 
analysis data? Either XRF or ICP-MS would give a good guide to the sample 
composition, and it should match to the composition you are using in the 
structure model.

I find it is worth drying both the sample and spike before weighing them, as 
you can introduce some errors if one component likes to adsorb a lot of water 
from the air. And are you sure your spike is fully crystalline (95% or more), 
is intimately mixed with the sample and doesn't have massively different 
particle size to the sample?


Jools


-Original Message-
From: rietveld_l-requ...@ill.fr  On Behalf Of 
François Goutenoire
Sent: onsdag 3. mars 2021 13.34
To: rietveld_l@ill.fr
Subject: Hyper-Lorentzian effect on quantitative analysis

Dear Rietveld users,

I have some industrial compound presenting a strong hyper-Lorentzian peak shape 
(eta=1.1 with HighScore). When we calculate the amorphous content after an 
internal standard addition, the result is 40%. The micro-absorption effect has 
been minimized (mu of the internal standard is closed to the compound).

But with some electronic transmission analysis no amorphous is observed.

The question is : Does a strong hyper-Lorentzian peak shape could influence 
quantitative analysis ?

François

--
*
Pr. Francois GOUTENOIRE
e-mail: francois.gouteno...@univ-lemans.fr
Tel: 02.43.83.33.54
FAX: 02.43.83.35.06
Skype Entreprise visio conférence
Département des Oxydes et Fluorures
Institut des Molécules et des Matériaux du Mans IMMM - UMR CNRS 6283 Université 
du Maine - Avenue Olivier Messiaen
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RE: Bruker D8-Discover

[Julian Richard Tolchard]

Davide,

It seems to me that burning out 3 control boards in a short space of time is 
obviously abnormal for any instrument. I would recommend talking directly to 
Bruker about it.


jools


From: rietveld_l-requ...@ill.fr  On Behalf Of Davide 
Levy
Sent: onsdag 23. oktober 2019 10.29
To: rietveld_l@ill.fr
Subject: Bruker D8-Discover

Good Morning,
I would like to have an opinion from other user of Bruker diffractometers.
I have a D8-discover, it is about 8 years old. In the last few month 3 boards 
for the motors burned and were changed.  Is it normal ? or can it be that there 
is another problem in the control rack ?
Thanks for your help
Davide

Dr. Davide Levy, Ph.D.
Head of XRD laboratory
Wolfson Applied Materials Research Center
Tel Aviv University
Phone: +972-3-6407815
Fax:   +972-3-6407819
http://www3.tau.ac.il/wamrc/ 

[cid:image001.jpg@01D58A49.7FB965C0][WAMRC-LOGO_new]

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RE: [EXTERNAL] Mounting Sample on High Temperature XRD Ribbon Heater

[Julian Richard Tolchard]

Andrew,

I agree completely. Pt does definitely have its problems, but it's hard to get 
radiant heaters that go so high in temperature.

My feeling is that if you want to pursue HT-XRD in any serious fashion you need 
to accept the idea that Pt / Ta strips and thermocouples etc are "consumables" 
and live with the associated cost. I know this is difficult for a lot of 
university labs, but once you adopt that mindset you can do much more 
interesting experiments.


Jools


From: Payzant, Andrew 
Sent: torsdag 25. juli 2019 17.08
To: Julian Richard Tolchard ; Mibeck, Blaise 

Cc: rietveld_l@ill.fr
Subject: Re: [EXTERNAL] Mounting Sample on High Temperature XRD Ribbon Heater

Jools,

You are right. “Lab grade” bottled N2 may have enough residual oxygen to cause 
problems, plus it is hard to purge the chamber properly to get the pO2 low 
enough to avoid issues.  But an H2/N2 mix might not be suitable, especially if 
it destabilizes his sample. Here are some other ideas:


  1.  I used to flow high purity N2 through a gettering furnace in series with 
the HTXRD chamber, and that, coupled with multiple purges of the chamber prior 
to starting the experiment, worked pretty well.
  2.  I have in the past used a Bühler HT furnace that had a secondary 
“surround heater” option. I had some success putting a gettering wire across 
these leads and running it at a higher temperature than the heater strip in 
order to remove traces of oxygen from the chamber. This has the advantage that 
as you heat up the walls of the chamber and release adsorbed oxygen it goes to 
the getter rather than the strip. It can be a bit tricky ensuring that the 
getter is hotter than the strip across the range of temperatures that you run.

However, I fully agree with you that a platinum foil is probably a better 
option for Blaise’s experiment. If he has one handy.

There are some caveats regarding platinum though. It is generally more 
expensive. It is readily attacked by silicon, iron, and other elements. You can 
get recrystallization and/or rapid grain growth at high temperatures, which 
dramatically changes the diffraction pattern from the strip during a HTXRD 
experiment. The relatively high CTE means that the strip height will change as 
the temperature increases, which will cause large peak shifts unless you are 
using parallel beam optics and even then will cause intensity variations at the 
lower 2thetas. If you work at a US government lab, platinum is a precious metal 
and there is some paperwork required every time you change heater strips. Also, 
if your sample melts or sinters, you may have some “fun” getting the platinum 
clean.

Andrew

*

Dr. E. Andrew Payzant
Materials Engineering Group Leader
Neutron Scattering Division
Neutron Sciences Directorate

Mailing address:
Oak Ridge National Laboratory
Dr. E. Andrew Payzant
P.O. Box 2008
Bldg. 8600, MS 6475
Oak Ridge, TN 37831

cell: (865) 235-4981
email: payza...@ornl.gov<mailto:payza...@ornl.gov>
https://www.ornl.gov/staff-profile/e-andrew-payzant

**



From: Julian Richard Tolchard 
mailto:julianrichard.tolch...@sintef.no>>
Date: Thursday, July 25, 2019 at 10:47 AM
To: "Mibeck, Blaise" mailto:bmib...@undeerc.org>>, Andrew 
Payzant mailto:payza...@ornl.gov>>
Cc: Rietveld list mailto:rietveld_l@ill.fr>>
Subject: RE: [EXTERNAL] Mounting Sample on High Temperature XRD Ribbon Heater

Actually, i wouldn't recommend that either 

My experience with the Ta heaters is that they react with even the smallest 
amount of oxygen, and bottled N2 has more than enough to kill a Ta strip. The 
best result we had was with a H2/N2 mix, but that still failed (probably 
reaction with the sample).  Personally I think the only reliable way to use 
them is with a high vacuum system (turbo pump), and with relatively inert 
samples.

Ultimately you are better off getting a Pt strip instead.


Jools


From: rietveld_l-requ...@ill.fr<mailto:rietveld_l-requ...@ill.fr> 
mailto:rietveld_l-requ...@ill.fr>> On Behalf Of 
Mibeck, Blaise
Sent: torsdag 25. juli 2019 16.27
To: Payzant, Andrew mailto:payza...@ornl.gov>>
Cc: rietveld_l@ill.fr<mailto:rietveld_l@ill.fr>
Subject: Re: [EXTERNAL] Mounting Sample on High Temperature XRD Ribbon Heater

Thank you -- I will try nitrogen then!



From: Payzant, Andrew mailto:payza...@ornl.gov>>
Sent: Thursday, July 25, 2019 9:08 AM
To: Mibeck, Blaise mailto:bmib...@undeerc.org>>
Cc: rietveld_l@ill.fr<mailto:rietveld_l@ill.fr> 
mailto:rietveld_l@ill.fr>>
Subject: Re: [EXTERNAL] Mounting Sample on High Temperature XRD Ribbon Heater


STOP!!!



The tantalum foil should not be used for high temperature in air. Above a few 
hundred degrees Celsius it will oxidize rapidly and disintegrate.

I accidently learned this the hard way many years ago!  

RE: [EXTERNAL] Mounting Sample on High Temperature XRD Ribbon Heater

[Julian Richard Tolchard]

Actually, i wouldn't recommend that either 

My experience with the Ta heaters is that they react with even the smallest 
amount of oxygen, and bottled N2 has more than enough to kill a Ta strip. The 
best result we had was with a H2/N2 mix, but that still failed (probably 
reaction with the sample).  Personally I think the only reliable way to use 
them is with a high vacuum system (turbo pump), and with relatively inert 
samples.

Ultimately you are better off getting a Pt strip instead.


Jools


From: rietveld_l-requ...@ill.fr  On Behalf Of 
Mibeck, Blaise
Sent: torsdag 25. juli 2019 16.27
To: Payzant, Andrew 
Cc: rietveld_l@ill.fr
Subject: Re: [EXTERNAL] Mounting Sample on High Temperature XRD Ribbon Heater

Thank you -- I will try nitrogen then!



From: Payzant, Andrew mailto:payza...@ornl.gov>>
Sent: Thursday, July 25, 2019 9:08 AM
To: Mibeck, Blaise mailto:bmib...@undeerc.org>>
Cc: rietveld_l@ill.fr 
mailto:rietveld_l@ill.fr>>
Subject: Re: [EXTERNAL] Mounting Sample on High Temperature XRD Ribbon Heater


STOP!!!



The tantalum foil should not be used for high temperature in air. Above a few 
hundred degrees Celsius it will oxidize rapidly and disintegrate.

I accidently learned this the hard way many years ago!  



Either use an inert atmosphere or vacuum. Or use a different heater ribbon, 
suitable for air atmosphere.



Andrew



*



Dr. E. Andrew Payzant

Materials Engineering Group Leader

Neutron Scattering Division

Neutron Sciences Directorate



Mailing address:

Oak Ridge National Laboratory

Dr. E. Andrew Payzant

P.O. Box 2008

Bldg. 8600, MS 6475

Oak Ridge, TN 37831



cell: (865) 235-4981

email: payza...@ornl.gov

https://www.ornl.gov/staff-profile/e-andrew-payzant



**







From: mailto:rietveld_l-requ...@ill.fr>> on behalf 
of "Mibeck, Blaise" mailto:bmib...@undeerc.org>>
Reply-To: "Mibeck, Blaise" mailto:bmib...@undeerc.org>>
Date: Thursday, July 25, 2019 at 10:03 AM
To: Rietveld list mailto:rietveld_l@ill.fr>>
Subject: [EXTERNAL] Mounting Sample on High Temperature XRD Ribbon Heater





I am looking for advice on how to prepar a HTXRD sample (mounting techniques, 
stage preparation, etc...). The ribbon heater is tantalum (brand new). The 
sample contained ammonium di-hydrogen phosphate. The atmosphere is air.



I hope to reach at least 1100C, but have had the ribbon break before 750C. 
Corrosion? or can the sample lower electrical resistance?



Please, any advice.



All the best,

Blaise








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Topas reporting macro

[Julian Richard Tolchard]

Hi all, 

A quick question - does anyone know an easy way to export the individual fits 
for xo_Is type peaks in Topas? I just want a 2 column file for each peak (or a 
collated file of all) that i can plot.  

I can't find anything in the documentation and my usual info repository (John 
Evans' Topas wiki) seems to be offline. 

Thanks, 


jools
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RE: atomic position

[Julian Richard Tolchard]

As a point of semantics, how exactly is copyright enforced with respect to the 
content of these databases? The crystal structures are in most cases published 
elsewhere, so there is no way that ICDD or ICSD can "own" them in any way. And 
even if claimed they did, can a crystal structure actually be copyrighted, as 
it is hardly a creative work?


jools



From: rietveld_l-requ...@ill.fr [rietveld_l-requ...@ill.fr] on behalf of Alan 
Hewat [alan.he...@neutronoptics.com]
Sent: 14 June 2016 11:06
To: Matteo Leoni
Cc: Rachid Abkar; rietveld_l@ill.fr
Subject: Re: atomic position

On 14 June 2016 at 10:16, Matteo Leoni 
>
 wrote:
However, please update your records. The PDF-4+ is not the PDF-2. The PDF-4+ 
... contains also most of the ICSD coordinates that have been however 
thoroughly checked in house, quality marked, cross referenced and corrected 
when needed.

Thank you for the correction :-) As I wrote, both databases are copyright, and 
since the ICSD is more complete (and probably less expensive) my advice to 
purchase that is still valid, though you can already find publications with 
Google. ICSD entries have also been "thoroughly checked in house, quality 
marked, cross referenced and corrected when needed."
__
   Dr Alan Hewat, NeutronOptics, Grenoble, FRANCE
 +33.476.98.41.68

http://www.NeutronOptics.com/hewat
__
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RE: Parafocussing definition?

[Julian Richard Tolchard]

The prefix "para-" has several definitions, one of which is "abnormal, 
incorrect" or "resembling". I assumed this prefix was used because BB geometry 
uses the focusing condition but is not truly a focusing geometry: The 
diffractometer circle and focusing circle being different causes the focusing 
circle (the circle on which the source, sample and detector lie) to effectively 
become smaller as a function of increasing 2-theta.

I didn't think the sample flatness had so much to do with it, because even if 
you define the sample to be infinitely small (or curved) you will still change 
the radius of the focusing circle with changing 2-theta.


jools


From: rietveld_l-requ...@ill.fr [mailto:rietveld_l-requ...@ill.fr] On Behalf Of 
ian.mad...@csiro.au
Sent: 2. mai 2016 10:06
To: rietveld_l@ill.fr; rowle...@gmail.com
Subject: Re: Parafocussing definition?


Hi Matthew,



I've got some nice figures from an old XRD Basics presentation from decades ago 
- the problem is that all this stuff is in my CSIRO office and I'm at home!



However, I will do my best to recall the basic principles of parafocusing In a 
Bragg-Brentano instrument:-

  1.  The source (tube target) and receiving slit are both on the 
diffractometer circle (not to be confused with the focusing circle) and are 
equidistant from the diffractometer (rotation) axis.
  2.  The beam is divergent (strictly speaking, a parallel beam instrument is 
not Bragg-Brentano geometry).
  3.  The sample is an extended flat plate.
  4.  The centre line of the incident beam will strike the sample at the centre 
of the diffractometer rotation axis (assuming the instrument is well aligned 
and the sample properly presented - not always a given!) at some angle theta. 
This beam will diffract from crystal planes parallel to the surface to the 
receiving slit also at an angle theta (yippee - theta + theta = 2theta - I'm a 
maths wiz)
  5.  The lower extremity of the diverging incident beam will strike the sample 
on the tube side of the diffractometer rotation axis at some angle (theta + 
phi). Now (and this is where the magic comes in) this beam will diffract from 
planes rotated phi degrees to the surface - for the same reflection as in 4. 
above, this means that the diffracted beam now makes an angle of (theta - phi) 
to the surface. Now (theta + phi) + (theta - phi) = 2theta - still amazing.
  6.  The upper extremity of the diverging incident beam will strike the sample 
on the detector side of the diffractometer rotation axis ... follow reasoning 
above for planes rotated -phi with respect to the sample surface.
  7.  This works because (this is the important bit) within a circle equal arcs 
make equal angles - a simple ray tracing diagram will help here.
  8.  Part of the reason Bragg-Brentano instruments have good intensity is due 
to the fact that the diverging beam will diffract from a wider range of 
crystallite orientations than say a parallel beam instrument.
  9.  There is no true 'focusing' of the X-ray beam in this context - the 
apparent focusing is happening because of 4 - 6 above in the context of 
diverging beams.
  10. I don't think that flat vs curved sample needs to come into this 
explanation.

I hope this helps.

​


Cheers



ooo0ooo

 Ian Madsen
 Honorary Fellow
 CSIRO Mineral Resources Flagship
 Private Bag 10,  Clayton South 3169
 Victoria,   AUSTRALIA
 Phone +61 3 9545 8785 direct
 +61 3 9545 8500 switch
 +61 (0) 417 554 935 mobile
 FAX+61 3 9562 8919
 Email ian.mad...@csiro.au

ooo0ooo

From: rietveld_l-requ...@ill.fr 
> on behalf of 
Matthew Rowles >
Sent: Monday, May 2, 2016 3:52 PM
To: RIETVELD_L Distribution List
Subject: Parafocussing definition?

Hi all

I've been trying to find a good explanation of what parafocussing (wrt 
Bragg-Brentato geometry) actually is, but haven't been able to find one.

Klug and Alexander just reference Brentano's papers.

"The Basics of Crystallography and Diffraction" 2nd ed say that B-B geometry is 
"semi-focussing" because the sample is flat, and not curved to follow the 
focussing circle (this doesn't sound right to me)

Brentano, J Appl. Phys. 17, 420 (1946) says that a ray reflecting off the arc 
defined by ACB where A is the source, C is the centre of the gonio, and B is 
the detector (ie the focussing circle)  is automatically parafocussing, because 
you only can establish the location of the crystallites, not their orientation, 
but then goes on to say that you can actually find the orientation, as the 
lattice plane normal bisects the angle ACB.

I also haven't been able to find a use of the word "parafocus" outside 

RE: Aking for Advice - reduce the current to X-ray tube to avoid director saturation at low angels

[Julian Richard Tolchard]

Shay,

Can we assume you are working with a reflection mode instrument?

You have two primary sources of background - the primary beam hitting the 
detector directly, and x-rays scattering from the air rather than the sample.

The first of these you control with the divergence slits, but really shouldn't 
be a problem until you go below 4-5 degrees. If you do scan from those sorts of 
angles, set the divergence slits to ~0.1 degrees to keep the beam on the 
sample. I haven't tested it myself, but you could also try reducing the 
detection window on the LynxEye if you want to go to really low angles (<2 
degrees).

The air scatter can be reduced with a special screen/knife that you should have 
received with the instrument, and correctly aligned it will reduce a lot of the 
background increase you see below 10-15 degrees 2-theta. There should be some 
instructions in the instrument manual about this. Using a smaller divergence 
slit (and a receiving slit if you have the option) will also reduce the 
background from airscatter.

I don't think that lowering the tube power will help very much,


jools








From: rietveld_l-requ...@ill.fr [rietveld_l-requ...@ill.fr] on behalf of Shay 
Tirosh [stiro...@gmail.com]
Sent: 06 March 2016 10:51
To: rietveld_l@ill.fr
Subject: Aking for Advice - reduce the current to X-ray tube to avoid director 
saturation at low angels

Dear Rietvelders

I would like to avoid director saturation (we have a LYNXEYE detector) when I 
work at low angles (lower then 10deg).
I thought it would be good to lower the current tube to reduce the current. say 
to 35mA instead of 40mA.
Can you please comment on problems it should encounter?
Can I correct problems by slowing down my scanning time?

Thank you from advance
Shay

--
_

Dr. Shay Tirosh
Institute for Nanotechnology & Advanced Materials
Bar Ilan University
Ramat Gan, 52900
Israel
Phone: +972-(0)30-531-7320
Mobile: +972-(0)54-8834533
Email: stiro...@gmail.com
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Quantitative internal standards

[Julian Richard Tolchard]

Hi all,

I've been asked to do some quantification on some samples which are 
predominantly silica, which means a reasonable amorphous component is pretty 
much inevitable. I'm thus looking for a suitable internal standard for spiking, 
but as this could be quite a big project moving forwards i don't think the NIST 
standards are financially viable. Does anyone have any good sources for spikes 
to use with such light materials?

Regards,


jools

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RE: Proposal to avoid banning for attachments in the list

[Julian Richard Tolchard]

There is a reality here that the web is really a shifting sands of information. 
So the idea we link to images and files we wish to refer to is probably flawed, 
and is not going to achieve the archive role that would be desirable, simply 
because those links will be broken or lost in a few months (maybe a couple of 
years) when the associated host website is re-organised or simply shut down. I 
don't believe that we can achieve the desired goal of a reference archive of 
the mail list in this way, but only by storing files within the mail list. That 
of course is additional overhead.

In that case, the argument against attaching images and files really becomes 
one about data transfer sizes (processing large amounts of data) and the 
spreading of viruses in attachments. In this case imposing a file-size 
limitation is a sensible policy, and i think for people reading the archives in 
2 or 3 years it will give exactly the same result as having a broken embedded 
web link.

I agree with Alan though, that it would be better to have a full permanent 
archive including files and images for reference. What are the options for this?


jools


From: alan.he...@gmail.com [mailto:alan.he...@gmail.com] On Behalf Of Alan Hewat
Sent: 15. juli 2015 08:34
To: Fabrizio Guzzetta
Cc: rietveld_l@ill.fr
Subject: Re: Proposal to avoid banning for attachments in the list

Dear Fabrizio.

1) I would be happy if you or other members created such a dropbox to allow 
people to post images, linking to them in their Rietveld posts. The main 
problem with images is simply that they are not archived on 
http://www.mail-archive.com/rietveld_l@ill.fr/ so are not available for future 
reference.

2) But apparently not everyone thinks their images need be archived - you 
yourself propose they be deleted after one month. In that case, I propose that 
since we already made an exception for Jim, as a test, we allow such people to 
post small images (75 kbyte) directly to the Rietveld mailing list.

They will not be archived, and I personally think that reduces the interest of 
the archive, but I concede that other people have a different opinion. Vive la 
difference !

Alan

On 15 July 2015 at 08:12, Fabrizio Guzzetta 
fabrizio.guzze...@gmail.commailto:fabrizio.guzze...@gmail.com wrote:

I have seen, in the past, that the argument of attachments in the mails/reply 
is always under debate and I understand both parties, the one that is 
pro-attachments because we are visual in the senwe that an image can explain 
better than tons of words sometimes or for particularly difficult patterns to 
visualize, particular problems which can't be resolved with proper data posting 
and so on, and the other one which has designed the mailing list this way, 
probably to avoid scams/viruses/etc...

So I want to make my proposal: why don't we create a virtual space in the 
clouds (e.g. dropbox), shared between the Rietvelders/crystallographers where 
the attachments will be put according to specific arguments (and date), and 
moderated in turn by few rietvelders (who can and want to do this, nothing is 
imposed) to erase data every month (or so) old data previous an email 
remainding when old data will be deleted? This will also eliminate or  reduce 
the needs for hyperlinks.

I hope not to be crucified and especial y I ask Alan (who created this list) an 
opinion on that.

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--
__
   Dr Alan Hewat, NeutronOptics, Grenoble, FRANCE
alan.he...@neutronoptics.commailto:alan.he...@neutronoptics.com 
+33.476.98.41.68
http://www.NeutronOptics.com/hewat
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RE: Cyberstar hot air blowers

[Julian Richard Tolchard]

I bought Leister Mini a couple of years ago. It is a complete system (excluding 
an air supply) for around 2500 CHF purchased here. It doesn't blow a lot of hot 
air, but more than enough to heat up a capillary. The TC is not particularly 
sophisticated either, and i don't think has the option of external control (i 
could be wrong on that though). But it does a good job for a cheap all-in-one 
unit.

I also looked at these 
http://www.sylvania.com/en-us/products/air-heaters/process-air-heaters/Pages/series-i-ii-iii.aspx,
 but then a separate TC is needed.

One thing i did notice when i was looking was that getting above 800C the 
choices thin out a lot, and the Cyberstar is the only one i found that goes 
over 900C.


jools



From: alan.he...@gmail.com [alan.he...@gmail.com] on behalf of Alan Hewat 
[alan.he...@neutronoptics.com]
Sent: 03 July 2015 13:02
To: Radovan Cerny
Cc: SAJ Kimber; rietveld_l@ill.fr; Yaroslav Filinchuk UCL
Subject: RE: Cyberstar hot air blowers


I was not complaining about the cost, just questioning what was quoted - only 
two thousand CHF ? Does that include a precise temperature controller - or just 
the hot air ?

_
  From my mobile telephone
 Dr Alan Hewat, NeutronOptics, Grenoble, FRANCE
alan.he...@neutronoptics.com +33.476.98.41.68
  http://www.NeutronOptics.com/hewat
_

On 3 Jul 2015 12:52, Radovan Cerny 
radovan.ce...@unige.chmailto:radovan.ce...@unige.ch wrote:
Complaining about the cost of small Swiss companies is not appropriate on the 
Rietveld list :)

On Facebook it would be automatically censored by BB …

I have the same heater, and once you calibrate it is quite stable and precise.

Destroying the samples is more expensive in the industry than in our labs …


Radovan Cerny
Laboratoire de Cristallographie, DQMP
Université de Genève
24, quai Ernest-Ansermet
CH-1211 Geneva 4, Switzerland
Phone  : [+[41] 22] 37 964 50, FAX : [+[41] 22] 37 961 08
mailto : radovan.ce...@unige.chmailto:radovan.ce...@unige.ch
URL: http://www.unige.ch/sciences/crystal/cerny/rcerny.htm

De : alan.he...@gmail.commailto:alan.he...@gmail.com 
[mailto:alan.he...@gmail.commailto:alan.he...@gmail.com] De la part de Alan 
Hewat
Envoyé : vendredi 3 juillet 2015 12:15
À : Yaroslav Filinchuk UCL
Cc : SAJ Kimber; rietveld_l@ill.frmailto:rietveld_l@ill.fr
Objet : Re: Cyberstar hot air blowers


2000 CHF? Precise temperature control is essential since often you will want to 
work near transitions where you risk destroying your sample. That also costs.

_
  From my mobile telephone
 Dr Alan Hewat, NeutronOptics, Grenoble, FRANCE
alan.he...@neutronoptics.commailto:alan.he...@neutronoptics.com 
+33.476.98.41.68
  http://www.NeutronOptics.com/hewat
_
On 3 Jul 2015 11:38, Yaroslav Filinchuk UCL 
yaroslav.filinc...@uclouvain.bemailto:yaroslav.filinc...@uclouvain.be wrote:
Hello Simon,

we are successfully using a programmable hot air blower (25-750°C) called Le 
Mini Sensor Kit 800, from the Swiss company Leister. It costs about 2000 CHF, 
and is aimed at the industrial use. It allows to do ramps, it follows the 
protocol very closely, but the temperatures and real ramp rates have to be 
calibrated.

Best regards,
Yaroslav



Friday, July 3, 2015, 10:38:50 AM, you wrote:

Dear All,

Sorry not a direct Rietveld question, but I hope somebody can help  : )

We often use high temperature (RT - 1000 C) gas blowers at ESRF for their 
flexibility and low background. Those made by Cyberstar seem to have become 
prohibitively expensive. Does anyone know of a competing supplier?

best wishes,

Simon

--
-
Dr. Simon A.J. Kimber
European Synchrotron Radiation Facility,
71 Avenue des Martyrs,
38000 Grenoble,
France.
0033 (0)47688 2773


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RE: polarization

[Julian Richard Tolchard]

I seem to remember i asked the same question about Goebel mirrors last year. 
The outcome of that, from the list and a private comm or two, was that they are 
theoretically challenging to calculate because they effectively act as a series 
of monochromators with varying acceptance angles.

The good news is that the acceptance angle is so low that you'll be fine just 
assuming that there is no polarization. I did try refining the polarization on 
a standard from our focusing Mo instrument, and it refused to budge from zero.


jools



From: leopoldosues...@gmail.com [leopoldosues...@gmail.com] on behalf of 
Leopoldo Suescun [leopo...@fq.edu.uy]
Sent: 03 June 2015 16:54
To: Matthey, Björn
Cc: Davide Levy; rietveld_l@ill.fr
Subject: Re: polarization

Dear Björn,

Since the Goebel mirror uses diffraction it should require the same polization 
factor than a crystal monochromator.

http://www.ccp14.ac.uk/ccp/web-mirrors/dirdif/xtal/documents/equipment/d8/accessories/goebel.html

you can get the equations from:

http://reference.iucr.org/dictionary/Lorentz%E2%80%93polarization_correction

Hope this helps,
Leo

2015-06-03 10:39 GMT-03:00 Matthey, Björn 
bjoern.matt...@ikts.fraunhofer.demailto:bjoern.matt...@ikts.fraunhofer.de:
Dear all,

what is he right factor in case of a laboratory diffractometer with „ sealed 
tube or rotating anode source” and especially for a goebel mirror?

Thank you in advance

Björn Matthey

--

Mit freundlichen Grüßen | Best Regards
Björn Matthey

Fraunhofer-Institut für Keramische Technologien und Systeme, IKTS Dresden
Dipl.-Ing. Björn Matthey
Keramografie, Phasenanalyse / Ceramography, Phase Analysis
Winterbergstraße 28, 01277 Dresden, Germany
Telefon +49 351 2553-7973tel:%2B49%20351%202553-7973
Fax +49 351 2554-280tel:%2B49%20351%202554-280
mailto: 
bjoern.matt...@ikts.fraunhofer.demailto:bjoern.matt...@ikts.fraunhofer.de
http://www.ikts.fraunhofer.de

Von: leopoldosues...@gmail.commailto:leopoldosues...@gmail.com 
[mailto:leopoldosues...@gmail.commailto:leopoldosues...@gmail.com] Im Auftrag 
von Leopoldo Suescun
Gesendet: Mittwoch, 3. Juni 2015 15:31
An: Davide Levy
Cc: rietveld_l@ill.frmailto:rietveld_l@ill.fr
Betreff: Re: polarization

Dear Davide,

The polarization factor depends on the incident X-rays not on the type of 
detector.
If your radiation comes from a sealed tube or rotating anode source without 
monochromator there is no polarization of light and the factor is 0.5, the use 
of a filter does not change the polarization state.
If  you have an incident beam monochromator it depends on the material of the 
monochromator (or better on the diffraction angle).
If you are using synchrotron radiation you will need something in the range 
0.95 to 1 depending on the optics of the beamline.
I hope this helps,
Leo


2015-06-03 5:56 GMT-03:00 Davide Levy 
davide.lev...@gmail.commailto:davide.lev...@gmail.com:
Hi to everybody,
Which polarization correction is better to use in GSAS for data collected with 
a linear detector without monochromator?
thanks
Davide

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--
Dr. Leopoldo Suescun
Prof. Agr (Assoc. Prof.) de Física  Tel: (+598) 
29290705tel:%28%2B598%29%2029290705/29249859
Cryssmat-Lab./Cátedra de Fisica/DETEMA  Fax: (+598) 
29241906tel:%28%2B598%29%2029241906*
Facultad de Quimica, Universidad de la Republica. Montevideo, Uruguay

Ahora la cristalografía importa más (www.iucr.orghttp://www.iucr.org/) 
Crystallography Matters more.



--
Dr. Leopoldo Suescun
Prof. Agr (Assoc. Prof.) de Física  Tel: (+598) 29290705/29249859
Cryssmat-Lab./Cátedra de Fisica/DETEMA  Fax: (+598) 29241906*
Facultad de Quimica, Universidad de la Republica. Montevideo, Uruguay

Ahora la cristalografía importa más (www.iucr.orghttp://www.iucr.org/) 
Crystallography Matters more.
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RE: regress in crystallographic good practices and knowledge

[Julian Richard Tolchard]

I also agree that it serves a purpose, even though it is much quieter compared 
to when i first joined many years ago. I would not want to see it closed down, 
as there are questions coming up from time to time that would be very hard to 
get answered anywhere else.

As Kurt suggests – why not just block attachments at the mail server?


jools

From: rietveld_l-requ...@ill.fr [mailto:rietveld_l-requ...@ill.fr] On Behalf Of 
Kurt Leinenweber
Sent: 8. mai 2015 18:17
To: Alan Hewat; Leopoldo Suescun
Cc: rietveld_l@ill.fr
Subject: RE: regress in crystallographic good practices and knowledge

Hi Alan,

I still like the Rietveld list and do read all the posts.

Is it possible to block attachments so that people can’t attach files any more?


-  Kurt

From: alan.he...@gmail.commailto:alan.he...@gmail.com 
[mailto:alan.he...@gmail.com] On Behalf Of Alan Hewat
Sent: Friday, May 08, 2015 9:07 AM
To: Leopoldo Suescun
Cc: rietveld_l@ill.frmailto:rietveld_l@ill.fr
Subject: Re: regress in crystallographic good practices and knowledge

I apologize in advance for attaching a file but I cannot share my astonishment 
without it.
that´s why I worry more and more every day.

And I worry that people are still attaching files to the whole list when they 
are explicitly asked not too. Most papers are on-line now, so just give a link 
to the paper. Or post your file to a free file sharing service - see: 
http://en.wikipedia.org/wiki/Comparison_of_file_hosting_services

Anyone who still posts files to the whole list is automatically suspended for 1 
week.

Actually, I worry that the Rietveld list no longer serves a useful purpose. 
There are few interesting discussions, and apparently few people actually read 
the posts.

Alan
__
   Dr Alan Hewat, NeutronOptics, Grenoble, FRANCE
alan.he...@neutronoptics.commailto:alan.he...@neutronoptics.com 
+33.476.98.41.68
http://www.NeutronOptics.com/hewat
__
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