Which laboratories or institutes in Iran are able to determine estrogen hormone concentrations?

Dear researchers, I want to determine the estrogen hormone concentration in water. Where is the special laboratory to do this in Iran? Could you please guide me? Best regards

11 December 2019 5,705 2 View

How can we calculate the amount of residual non-solvent (pore-former) additives in the membranes?

Dear researcher, We all use the non-solvent additives to improve the structure and performance of the polymeric membranes. However, the non-solvent additives can be easily washed out quickly with...

11 December 2019 5,714 1 View

How can I prepare the polymeric solutions ( polymer+solvent) without using magnets because of removing the PTEE white coating of magnet during mixing?

Dear researchers, I want to produce PES solutions using DMSO as the solvent. I have some tiny white particles in my polymeric solutions even after 48 h mixing using magnetic stirrer at 50 C. I...

09 October 2019 7,755 6 View

Is it true to consider the long macrovoids of a porous membrane as micro-channels?

Hi researchers, Based on the SEM images of the membrane cross section, at the sub-layer of a porous membrane, there are many long macro-voids. Can these macro-voids be considered as...

09 October 2019 7,597 2 View

Can Ethyl lactate dissolve the polysulfone family polymers?

Dear researchers, Ethyl lactate is a green solvent which can be replaced by toxic solvents such as DMAc, DMF, NMP, etc. But there are only a few reports for CA/Ethyl lactate. It seems this solvent...

07 August 2019 4,221 11 View

What is the reason for inserting RO modules "horizontally" in water treatment companies?

Hi researchers, The RO modules are designed in "horizontal packs" in water treatment companies. What is the reason? Could you please give me a reference? Regards Foroogh

31 December 2018 4,971 9 View

How can we estimate the bound water in a dried porous solid and the appropiriate residual moisture concentration?

We all know that during solid drying, free water and bound water has two different mechanisms. How can we estimate the bound water concentration in a porous solid?

08 September 2018 9,735 2 View

What is the difference between mixed polymer solutions by different kinds of impellers (mixer blades)?

Dear researchers, I used 3 different impellers to prepare the same polymer solution (fixed composition) which their pictures were attached. Why the prepared polymer solutions have different...

08 September 2018 7,674 22 View

What is the effect of turbulence and reynolds number on polymer solution properties during mixing step?

Dear researchers, I am preparing polymer solutions with this composition: Polymer= PVDF - 18 wt% Additive= PEG200- 5 wt% Solvent= DMAc- 77 wt% Firstly DMAc+ PEG mix at 100 rpm and 25 C and then...

08 September 2018 9,483 7 View

What are important differences between Lab-scale (glass bottle-50gr) and Pilot-scale (buchi vessel- 1 kg) polymer solution preparation?

Dear researchers, I am producing polymer solutions in both Lab and Pilot scales for membrane manufacturing. What are important differences between Lab-scale (glass bottle-50gr) and Pilot-scale...

08 September 2018 5,074 12 View

what is the simplest definition of ion exchange capacity

What this unit identifies for the ion exchange capacity ca. 0.92 meq. g-1. I am a newcomer in the membrane area. I just started. I highly appreciate your help

08 May 2021 0 0 View

what is the simplest definition of ion exchange capacity

What this unit identifies for the ion exchange capacity ca. 0.92 meq. g-1. I am a newcomer in the membrane area. I just started. I highly appreciate your help

08 May 2021 0 0 View

Looking for Materials with high thermal expansion coefficient and high temperature resistance?

03 March 2021 8,272 1 View

What are anisotropic electrical and optical properties of a semiconductor due to?

In some materials, properties such as band gap, thermal conductivity differ along different crystallographic axes. What are the basics?

01 March 2021 1,923 3 View

What are the countries most affected by extreme rainfall as a result of climate change?

Increased heat, drought and insect outbreaks, all associated to climate change, have increased wildfires. Decreasing water supplies, declined agricultural yields, health impacts in cities owing to...

01 March 2021 7,168 9 View

What is recommended for solid domain in ANSYS FLUENT?

Should I mesh the solid domain ? or should I use wall thickness? or Shell conduction? for Heat Transfer between two fluids of a Heat Exchanger. what is recommended?

01 March 2021 9,785 3 View

Heat exchanger with liquid Nitrogen as coolant?

I want to cool Natural Gas from 195 Kelvin to 138 Klevin in a heat exchanger by using liquid nitrogen as the coolant medium. When entering the heat exchanger, the liquid nitrogen will have a...

01 March 2021 6,450 5 View

How can i resolve the "final solutuin is not converged" error in Comsol for my heat transfer simulation??

I have been trying to simulate heat transfer problem in Comsol 5.5 for long time but it always throw an error stating: "Failed to find a solution. Maximum number of Newton iterations...

28 February 2021 8,626 3 View

1 nm thick MgO thin-film to be deposited on Si wafer using thermal evaporation. What will be the optimum deposition conditions?

Favourable conditions of base pressure, rate of deposition. Also, by which characterisation technique to be used to verify the thickness of the deposited film.

28 February 2021 3,640 3 View

Dapi fluorescence protocol for colon cell lines ?

28 February 2021 2,534 2 View