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Questions related from Rajeev Roychand
Do all iron containing compounds show fluorescence in XRD with copper radiation or just the oxides of iron show this effect? Say for instance if i have pure tetracalcium aluminoferrite (C4AF) or...
06 June 2019 6,751 2 View
I have got a slag sample that contains high amount of iron in it. I conducted xrd using Cu tube, on the powdered sample with very high background (because of iron efflorescence). Then to improve...
06 June 2019 1,730 6 View
I did XRD on anhydrous sodium sulfate salt (purity>99%) which i bought couple of months ago. For some reason sodium sulpfate peaks from PDF database (anhydrous or hydrated) don't align with the...
03 March 2018 5,963 7 View
I submitted a research paper to one of the Elsevier journals and got a response from the editor as below: "The paper has got 23 % similarity in total and from one single paper 10 %. However, if...
03 March 2017 4,178 3 View
Just wondering if anybody has done thermogravimetric analysis on pure hemi and mono carboaluminate phases? I am looking for the mass loss of chemically bound water. Based on the references I have...
12 December 2016 6,012 2 View
I have a slag sample with following elemental oxide composition:CaO, SiO2, Al2O3, MgO, SO3 and also contains carbonate bearing phase(s). I have identify the following phases in XRD:Gypsum...
11 November 2016 390 3 View
I have a slag sample with following elemental oxide composition: CaO, SiO2, Al2O3, MgO, SO3 and also contains carbon (in calcite). I have managed to identify the following phases: Gypsum...
11 November 2016 2,392 10 View
What are the important factors to select chebychev polynomial order for background function in TOPAS. If am checking the degree of crystallinity and I start with modelling the amorphous hump, do I...
11 November 2016 5,879 5 View
I have conducted TGA and XRD of 7 day hydrated sample containing cement, fly ash and nano silica. The TGA analysis show high amount of mass loss with an endothermic TGA peak located at about...
08 August 2016 7,608 6 View
I have a mix design of cement flyash blend. After doing rietveld refinement I have found that the ettringite percentage that was 1.57% at 7 days reduced to 0.85% at 28days. The gypsum content that...
07 July 2016 659 6 View
Is there any particular order that need to be followed for the rietveld refinement of hydrated cement samples in Bruker TOPAS. I have run rietveld refinement on one sample few times, even though I...
07 July 2016 1,768 7 View
I am using Bruker TOPAS for quantitative analysis of my hydrated cement samples. It gives error on loading CIF files. I initially thought the quality of CIF files from COD database could be an...
07 July 2016 8,300 11 View
What is the best crystalline material that can be used for the XRD quantitative analysis for cementitious materials, with the instrument having Cu Anode. Also, does the particle size have to be of...
07 July 2016 5,331 5 View
I am doing quantitative phase analysis of my hydrated cement paste sample at 7 day of curing. I have identified the following phases: Calcite, Larnite, Alite, Portlandite, Ettringite and...
06 June 2016 9,092 5 View
I am doing rietveld refinement of my hydrated cement paste samples and while varying various parameters I even sometime use flat plate absorption. That option brings about significant changes in...
05 May 2016 2,004 3 View
I am using fly ash and slag in my blended mix designs that have amorphous contents. I read somewhere that we can create hkl phase for the amorphous humps of fly ash and slag separately and then...
04 April 2016 485 4 View
Our XRD lab has only PDF2 database (ICDD), which i use with Brukers EVA search/match software. I have to do rietveld refinement of my hydrated cement paste samples but i can't retrieve cif files...
03 March 2016 4,335 11 View
Just wondering what is the best way to compare the hydration products of two mortar mix designs one with internally cured (25% SSD lightweight sand) and the other with 100% normal sand (control)?...
11 November 2015 5,616 1 View
The attached image shows a 28 day XRD spectra of a mix containing Cement, Fly ash, nano silica and alumina powder. There is an amorphous hump between 5 and 10 deg 2theta. The peak that i have...
07 July 2015 2,685 12 View
I am currently practicing image analysis software ImageJ so that I can use it in my experiment to quantify unreacted flyash and silica fume particles. My mix design contains cement, flyash and...
04 April 2015 5,838 7 View
Can anyone help me in providing me XRD peaks locations for C4AH12 (Calcium aluminate hydrate)? Also, i would highly appreciate if you could provide a reference article as well
01 January 2015 3,821 1 View
I have used Set accelerator in my blended cement mixes containing cement, flyash and nano silica. The strength of the mix containing SA is lower than the one without it. Set accelerator produced...
12 December 2014 562 2 View
I have got large amount of nano silica which i had ordered last year for my research, but after reading about risks associated with silica that can go into your body through breathing i'm bit...
07 July 2014 2,890 2 View
Some perform TGA under nitrogen environment and some under air. Also, some dry their samples before performing TGA and some do the TGA without drying the powdered hardened paste samples. If we dry...
05 May 2014 6,989 9 View
Can we have OPC as a control mix for a mix containing high early strength cement, fly ash and silica fume?
04 April 2014 9,578 5 View
I have to perform an accelerated carbonation test on cylindrical mortar samples. I am wondering if anybody knows what sort of epoxy can be used for covering the flat surfaces, so that only the...
04 April 2014 3,732 1 View
I am after high strength low density hollow spheres of any material glass, ceramic, etc. in the size range of about 5-10mm.
03 March 2013 3,971 3 View
Hi everyone, I have conducted an xrd on the waste tyre crumb rubber particles. It shows an amorphous hump centred around 20 degree two theta, few Zinc Oxide peaks and another two peaks (around...
01 January 1970 6,602 4 View