Can the Time weighted average (TWA) exposure concentration be estimated starting from the Short-Term Exposure Limit (STEL)?

Hello, I have got an MSDS indicating the STEL of a compound and I'd like to know what the relevant TWA would be. Is there a general ratio which roughly links the two parameters (regardless of the...

31 December 2019 4,439 4 View

How is water activity of pharmaceutical products measured?

Hello All, Which methodology should I follow to measure water activity of pharmaceutical materials? I am aware that there are two USP procedures in this regard, chapter 922 and 1112. Which of...

04 May 2019 4,158 5 View

How can I calculate the time per step if scan range, scan speed and step size are known?

Hello All, I am trying to reproduce an XRD method. I know scan range, scan speed and step size. How do I work out the time per step? Thanks, Antonio

05 June 2018 225 8 View

Could anybody provide references to water vapour pressure data at 25deg for the saturated solutions of the following salts?

I am just looking for references on water vapour pressures for the saturated solutions of the following salts: LiBr LiCl MgCl2 Mg(NO3)2 NaCl KCl KNO3 I have found the following reference...

02 March 2018 8,365 2 View

Could anybody suggest any (possibly pharmaceutical) material which could be used for PXRD proficiency testing?

I would like to fin out more information about which type of material (ideally pharmaceutical compounds) could be suitable to perform both qualitative and quantitative Powder X-ray diffraction...

31 December 2017 2,559 10 View

Could anybody suggest how to calculate the heat of adsorption/desorption from heat flow data (DSC) in mW?

Hi, I have got some DSC data related to the heat flow in mW (milliWatt I presume?) measured during adsorption/desorption of CO2 onto/from an activated carbon. I'm getting some inconsistent...

05 June 2015 3,006 5 View

Could anybody advise about the demineralization procedure of activated carbons?

01 February 2015 9,201 4 View

Could anyone recommend any companies in UK to purchase activated carbons from?

I'd need to purchase some activated carbons. Ideally, I would need two different type of products, a carbon having high micropore volume (d

06 July 2014 2,299 2 View

Has anybody been to any previous editions of the EUEC (Energy, Utility & Environment Conference)?

I'm planning to go to this year's edition in San Diego. It looks like a big event. My project is about CO2 capture so it kind of fits quite well in there. However, it would be nice to get some...

06 July 2014 2,669 1 View

What is the best technique for investigating the presence of CaO in a solid sample?

I've seen from the literature that XRF gives results in terms of oxides (e.g. CaO). Is this correct? What's the difference in terms of chemical composition results between XRF, XRD and EDX?

05 June 2014 716 15 View

After a reference from Int J Body Compos Res, can any body help?

Hi, I am after the reference below, my library says it cannot obtain a copy either locally or internationally, any help appreciated! Chris Wang ZM, Heshka S, Wielopolski L, Pi-Sunyer FX, Pierson...

03 March 2021 6,193 1 View

Can we block unwanted images during the x-ray prediction?

i am try to classify the x-ray images. During classification , can i block unwanted images (except x-ray image).

03 March 2021 7,100 1 View

Does anyone know to clarify these changes?

01 March 2021 1,290 2 View

How to remove the residual PDMS on the silicon mold?

Incompletely cross-linked pdms are difficult to remove.

01 March 2021 798 3 View

In an eye with Tyndall, does each dot correspond to an individual cell?

When you observe the presence of Tyndall in an inflamed eye: Does each of the small floating dots correspond to an individual cell or to an aggregate of cells? Does a conventional slit lamp have...

27 February 2021 6,326 2 View

How to calculate the crystallinity of cellulose film?

27 February 2021 2,753 4 View

What could be the reason for not having further low chi square value (better agreement) in my refinement result?

I have tried every combination of parameter changes and after that i have a poor chi square value. I can't get it lower any further. I know there have been a lot of discussion about Rietveld...

26 February 2021 8,480 3 View

Can anyone share his experience regards Smoothing in origin?

I am working on TiO2 composite material and the results of XRD have a lot of small/junk peaks and while I apply a smooth filter in Origin then the other characteristics peaks disappear so anyone...

26 February 2021 8,183 3 View

How to replicate the well conditions of a crystal hit with 20%(w/v) isopropanol?

I had a crystal hit in a well with 0.1M HEPEs pH 7.5, 10%(w/v) PEG 4000, and 20%(w/v) isopropanol. Why is isopropanol in w/v here if it's just solvent? How do I recreate this well condition?

25 February 2021 9,761 1 View

I have need of XRD graph analysis software for phase identification. Can you please provide links for software tools which can be downloaded?

i am trying to download x'pert high score software, but can't download it. please do suggest software for phase analysis

24 February 2021 5,687 4 View