Alex Gupta

9 Questions 6 Answers 0 Followers

Questions related from Alex Gupta

How can the Compression Stress on a membrane electrode assembly be calculated from the torque on the bolts of a proton exchange membrane fuel cell?

I'm trying to calculate the compression stress on the fuel cell components so that I can determine the porosity of the diffusion media as in the following paper: R. W. Atkinson, Y. Garsany, B. D....

12 November 2020 2,515 3 View

How to Quantify the Surface Concentration of Features on Particles in ImageJ?

I have AFM images of the topography of a sample which contains particles and tunneling AFM images of the current map over the particle surfaces. I have segmented the particle image (image showing...

16 September 2020 3,737 3 View

What energy value do I use to determine the mass attenuation coefficient for an element?

I would like to calculate the infinite thickness of a tungsten-containing sample for an x-ray fluorescence experiment. To calculate the infinite thickness, a mass attenuation coefficient is...

28 July 2020 6,253 1 View

How can the dopant concentration in a Nafion membrane be measured via XRF?

I am doping Nafion membranes with tungsten-containing molecular additives. I would like to measure the concentration (in wt%) of these additives inside of the membrane using x-ray fluorescence....

28 July 2020 7,505 2 View

Where is the heteropolyacid H3PW12O40 protonated?

Please refer to the attached images. The heteropolyacid should be protonated on the terminal oxygens, correct? Would protonation on the bridging oxygen cause disintegration of the...

06 April 2020 6,474 0 View

What is the best way to functionalize a silicon or silicon nitride surface with silanol groups?

I am trying to convert a silicon surface (SiO2 under normal conditions if I understand correctly) or silicon nitride surface of an AFM probe to a silanol surface with as complete of silanol...

08 February 2020 9,115 1 View

How can the surface of a fluorine-doped tin oxide film be hydroxylated?

We are working with glass pieces coated with a FTO film, as purchased from a supplier. We would like to covalently attach silane groups to the surface via reflux. First, we need to figure out how...

18 October 2019 8,725 2 View

How can solution resistance be determined?

We are trying to determine the conductivity of organic solutions (acetonitrile solvent). EIS gives negative solution resistance for these species. We are using a conductivity cell with two...

01 October 2019 3,359 3 View

How can I determine the grain size distribution of a perovskite film from SEM images?

I have an SEM image of a perovskite film (see attached). I want to determine the grain size distribution (histogram of grain size on x-axis vs. counts on y-axis). I am currently using ImageJ, but...

13 August 2019 1,182 17 View