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

error in running a model in Abaqus

Excessive rotation of nodes in node set ErrNodeExcessRotation-Step1

17 August 2021 0 0 View

error in modelling model in Abaqus

Excessive rotation of nodes in node set ErrNodeExcessRotation-Step1

17 August 2021 0 0 View

MGL tools

20 June 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

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

i have some problem with chtMultiRegionSimpleFoam

--> FOAM FATAL ERROR: Maximum number of iterations exceeded From function Foam::scalar Foam::species::thermo::T(Foam::scalar, Foam::scalar, Foam::scalar, Foam::scalar (Foam::species::thermo::*)(Foam::scalar, Foam::scalar) const, Foam::scalar (Foam::species::thermo::*)(Foam::scalar, Foam::scalar) const, Foam::scalar (Foam::species::thermo::*)(Foam::scalar) const) const [with Thermo = Foam::hConstThermo >; Type = Foam::sensibleEnthalpy; Foam::scalar = double; Foam::species::thermo = Foam::species::thermo >, Foam::sensibleEnthalpy>] in file /home/ubuntu/OpenFOAM/OpenFOAM-4.1/src/thermophysicalModels/specie/lnInclude/thermoI.H at line 66. FOAM aborting #0 Foam::error::printStack(Foam::Ostream&) at ??:? #1 Foam::error::abort() at ??:? #2 Foam::heRhoThermo >, Foam::sensibleEnthalpy> > > >::calculate() at ??:? #3 Foam::heRhoThermo >, Foam::sensibleEnthalpy> > > >::correct() at ??:? #4 ? at ??:? #5 __libc_start_main in "/lib/x86_64-linux-gnu/libc.so.6" #6 ? at ??:?

24 March 2021 0 0 View

How to compare two groups with only two measurements?

Hiiiii everyone! I have an enquiry on statistical analysis. I was looking for many forum and it's still cannot solve my problem. I want to compare means of two groups of data but only with two...

03 March 2021 8,796 3 View

Can we classify HV and LV lines based on line length?

I have dataset which shows the length of power lines. I need to classify the lines based on the line length. Is there a rule to classify the High voltage (HV) and low voltage (LV) lines based on...

03 March 2021 4,116 4 View

Enhanced Yellow Fluorescent Protein (Aequorea victoria) DNA sequence?

I am on the lookout for the Enhanced Yellow Fluorescent Protein (Aequorea victoria) DNA sequence. Does anyone know where I can find it? Thank you in advance

03 March 2021 3,568 1 View

What kind of fluid could I use for a pitfall trap that also does not invalidate molecular testing?

Hi, I want to start testing pitfall trap to obtain ants samples, but I need to conduct molecular analysis on those insects. So, what kind of fluid can I use? Ethanol expires too early and I need...

03 March 2021 5,978 5 View