Hi Tony, Thanks for your suggestion.
Yes, I tried scanning the major peak of the second phase with increasing temperature. I have good data. However, still I have the doubt of detecting the exact temperature of dissolution of the second phase. Looking forward to meet you at AIF. Best regards Apu On 5/3/14, Tony Wang <ian...@126.com> wrote: > Hi Apu, > > > > As you are running in situ scanning you probably cannot scan the sample for > long time. > > If you are only care about the accurate phase transforming temperature, you > can localize the scan range to the major peak for your second phase, which > will largely improve the detection limit, as Matteo suggested. > > Building some external calibration line may also help. > > > > Xiaodong (Tony) Wang > > Curtin University, coming to AIF > > > > From: rietveld_l-ow...@ill.fr [mailto:rietveld_l-ow...@ill.fr] On Behalf Of > Kurt Leinenweber > Sent: 2014年5月4日 6:05 > To: Habib Boughzala; ILL Forum > Subject: RE: Phase volume fraction > > > > Hi all, > > > > I think looking at the small diffraction peaks (or bumps) of the > low-fraction phase, and comparing them to any bumps that may or may not be > present in the actual data, could go a long way. But I do agree that some > more scientific analysis of the reliability of a very low phase fraction > would be merited. > > > > - Kurt > > > > _____ > > From: rietveld_l-requ...@ill.fr [rietveld_l-requ...@ill.fr] on behalf of > Habib Boughzala [habib.boughz...@ipein.rnu.tn] > Sent: Saturday, May 03, 2014 9:23 PM > To: ILL Forum > Subject: Re: Phase volume fraction > > > Hi everybody, > > > > I am very septic about the 1% of QPA detection limit and even less the 0.1% > in QPA e.s.d. since GSAS, FP, TOPAS, etc give different results for the > same sample with the same treatment. > > So I thing that we need drastically some scientific output in this field. > > > > Regards > > Habib > > > > Pr. Habib Boughzala > > I.P.E.I. Nabeul > > F.S.T Faculté des Sciences de Tunis > > A.T.C. Association Tunisienne de Cristallographie > > Tel 216 20523595 > > > > -------Original Message------- > > > > From: Leonid Solovyov <mailto:l_solov...@yahoo.com> > > Date: 02/05/2014 03:06:35 > > To: rietveld_l@ill.fr > > Subject: Re: Phase volume fraction > > > > Dear Martin, > > > > The main problems of the e.s.u. expressions used in Rietveld programs are > the neglect of correlations between residuals and the loss of > interrelations > between particular residuals and particular parameters in terms of their > mutual influence. > > Some references on the topic: > > J. Appl. Cryst. (1979). 12, 554-563 > > Acta Cryst. (1982). A38, 264-269 > > J. Appl. Cryst. (1983). 16, 159-163 > > J. Appl. Cryst. (1986). 19, 10-18 > > J. Appl. Cryst. ( 1991). 24, 1-5 > > J. Appl. Cryst. (1994). 27, 802-844 > > > > Best regards, > > Leonid > > ******************************************************* > > Leonid A. Solovyov > Institute of Chemistry and Chemical Technology > 660036, Akademgorodok 50/24, Krasnoyarsk, Russia > <http://sites.google.com/site/solovyovleonid> > http://sites.google.com/site/solovyovleonid > ******************************************************* > > _____ > > From: Martin Fisch <m_fi...@bluewin.ch> > To: Leonid Solovyov <l_solov...@yahoo.com> > Sent: Friday, May 2, 2014 2:59 PM > Subject: Re: Phase volume fraction > > > > Hi Leonid > > Everyone says that Rietveld s.u.'s are underestimated. Why is this? Is > there > any reference to this? > > Cheers, > Martin > > > > On 02.05.2014 09:57, Leonid Solovyov wrote: > > Dear Apu, > > > > If you use the Rietveld-based QPA you may assess the detection limit for a > phase from the estimated standard uncertainty of its weight (or volume) > fraction. In this case one should also take into account the fact that the > Rietveld standard uncertainties of QPA are underestimated about 2-3 times. > To have more realistic uncertainties you may use DDM: > > http://sites.google.com/site/ddmsuite/ > > http://sourceforge.net/p/ddmsuite > > > > Best regards, > > Leonid > > > > ******************************************************* > Leonid A. Solovyov > Institute of Chemistry and Chemical Technology > 660036, Akademgorodok 50/24, Krasnoyarsk, Russia > <http://sites.google.com/site/solovyovleonid> > http://sites.google.com/site/solovyovleonid > ******************************************************* > > _____ > > From: Apu Sarkar <mailto:apusar...@gmail.com> <apusar...@gmail.com> > To: "Leoni, Matteo" <mailto:matteo.le...@unitn.it> <matteo.le...@unitn.it> > > Cc: <mailto:rietveld_l@ill.fr> "rietveld_l@ill.fr" > <mailto:rietveld_l@ill. > fr> <rietveld_l@ill.fr> > Sent: Friday, May 2, 2014 3:41 AM > Subject: Re: Phase volume fraction > > > Yes, I meant detection limit. > In my sample I have a second phase which dissolves at some > temperature. I tried to identify the dissolution temperature using > XRD. With increasing temperature the peak intensity for the second > phase decreased. After certain temperature the peak disappeared. I > understand that is not exactly the dissolution temperature. There is a > limit of XRD to detect the phase. > > Thanks > Apu > > Department of Nuclear Engineering > NC State University > Raleigh, USA > > > > On 5/1/14, Leoni, Matteo <matteo.le...@unitn.it> wrote: >> I guess you are talking about detection limit only, not quantification >> limit, right? >> The answer largely depends on your material (scattering power, domain > size), >> tube (sampling volume) and counting time. I have seen cases where you can >> clearly see something below 0.1 wt% and cases where already the percent > was >> off limits. >> Matteo >> >> ----------------------------------------------------------------- >> >> Matteo Leoni, PhD >> >> DICAM >> University of Trento >> via Mesiano, 77 >> 38123 Trento >> Italy >> >> Tel +39 0461 282416 Fax +39 0461 282672 >> >> e-mail: matteo.le...@unitn.it >> ---------------------------------------------------------------- >> >> >> -----Messaggio originale----- >> Da: rietveld_l-requ...@ill.fr [mailto:rietveld_l-requ...@ill.fr] Per >> conto >> di Apu Sarkar >> Inviato: giovedì 1 maggio 2014 22.24 >> A: rietveld_l@ill.fr >> Oggetto: Phase volume fraction >> >> Hi, >> Can any one tell me what is the minimum phase volume fraction that can be >> detected by a laboratory X-ray diffractometer. In there any reference for >> this. >> >> I am using the new Empyrean from PANalytical. >> >> Thanks >> Apu >> >> Department of Nuclear Engineering >> NC State University >> Raleigh, USA >> > > > -- > Apu Sarkar > Postdoctoral Research Scholar > Department of Nuclear Engineering > North Carolina State University > > > Raleigh > USA > > > Mobile: 919-561-9244 > Website: https://sites.google.com/a/ncsu.edu/apu/ > > ++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++ > Please do NOT attach files to the whole list <alan.he...@neutronoptics.com> > Send commands to <lists...@ill.fr> eg: HELP as the subject with no body > text > The Rietveld_L list archive is on > http://www.mail-archive.com/rietveld_l@ill.fr/ > ++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++ > > > > > > > > > > > > > <http://www.incredimail.com/app/?tag=IM2_Default_Stamp_EN&id=509&lang=9&did= > 10500&ppd=2672,201106231034,1125,1,1953940704990396415&rui=156769540&app_tes > t_id=0&sd=20140503> > > -- Apu Sarkar Postdoctoral Research Scholar Department of Nuclear Engineering North Carolina State University Raleigh USA Mobile: 919-561-9244 Website: https://sites.google.com/a/ncsu.edu/apu/
++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++ Please do NOT attach files to the whole list <alan.he...@neutronoptics.com> Send commands to <lists...@ill.fr> eg: HELP as the subject with no body text The Rietveld_L list archive is on http://www.mail-archive.com/rietveld_l@ill.fr/ ++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
