Selecting particular columns from large datasets (csv) using R Studio?

So I have large number of csv files (100+) in a directory with same structure and column names. The data is in time series and there are approx 30 columns/file. However i only want to aggregate...

08 February 2021 245 5 View

Hey guys, I'm looking for an efficient protocol to transfect patient-derived tumor cells with a high rate of transient transfection?

As you know it's quite tricky to get primary cells transfected at a relatively high rate!

31 January 2021 3,580 4 View

How much pre-PCR dilution of mixed-template DNA extracted from pollen (honey) is appropriate for Metabarcoding?

I'm working on pollen DNA metabarcoding to identify the floral composition of honey. How much pre-PCR dilution of mixed-template DNA extracted from pollen (honey) is appropriate for the...

28 December 2020 9,132 1 View

How to add two vertical and parallel Fresnel reflection coefficients to retrieve overall reflection coefficient for a right hand circular wave?

I have a problem in which a right hand circular polarized wave (GPS wave) encounters an ideal smooth plane obliquely, and then is reflected off that. To solve this kind of problems, the wave is...

28 December 2020 2,271 3 View

Which is better to focus on teaching or research for a good academic life and Why?

Which is better to focus on teaching or research for For a good academic life and Why?

26 December 2020 5,737 9 View

Is ag paste suitable for back contact on silicon wafer? or i should deposit al on the back surface using pvd or plasma sputtering?

Fabricating silicon solar cell

22 December 2020 4,906 7 View

Which renewable source is the best ?

wind hydro solar etc.

21 December 2020 6,360 16 View

Why is light pure energy?

light is pure because the light is the simplest electromagnetic construct but the energy of any object is also of the same kind.

20 December 2020 207 4 View

How to handle Missing Values for Skipped Questions (Systematic Missing) in R ?

10 December 2020 435 4 View

What is the best industrial emulsifier to make silicon oil in water emulsion?

I need to make long-lasting stable emulsions of 6 wt. % percent silicon oil in DI water. The previousely made emulsions using Tween and Span Emulsifiers did not remain stable after a week.

31 October 2020 3,568 3 View

Polymer composites suddenly solidifies?

I am making polymer composite by solvent mixing method. When I am trying to add filler solution in polymer solution it quickly get solidified. How to make them then uinform? It doesn't give time...

03 March 2021 7,540 4 View

What solvent can I used for Paal Knorr reaction between 6-amino hexanoic acid and 2.5 hexanedione?

I am try to make the Paal Knorr reaction between 2.5 hexnedione and 6-amino hexanoic acid, my problem is type of solvent to use, because 6-hexaminohexanoic acid is soluble in water but I am not...

02 March 2021 4,443 2 View

How to polymerize TEOS?

I want to polymerize TEOS on a surface. I know that NH4OH is a preferred catalyst and an alcoholic solvent should be used .But I can not find certain amounts of each material to use. Does any one...

02 March 2021 1,404 6 View

Does Napabucasin soluble in dichloromethane and in ethanol?

I need to prepare a solution of Napabucasin (inhibitor of cancer cell stemness) in dichloromethane. The drug is expensive, so maybe somebody already tried to do it. If it is soluble, what is the...

02 March 2021 9,945 3 View

How can extract ciprofloxacin hydrochloride disolve in water er to organic solvent such as dichloromethan or any other solvent?

I need a procedure to extract the ciprofloxacin hydrochloride from aqueous solution by using dichloromethane in detail,. I thank you very much.

01 March 2021 4,306 1 View

How to separate water from glycerol solvent in a solvent recovery vacuum distillation column?

I am currently doing my third year design project. I have been assigned to design a glycerol recovery column in vinyl acetate monomer production. The process unit before the recovery column is an...

01 March 2021 9,525 4 View

What is the state of the drug inside solid lipid nanoparticles (SLNs)?

I am a little confuse with the mechanism of solid lipid nanoparticles (SLNs). The main point of encapsulating drugs into SLNs is because some drugs have low solubility in water. Therefore, SLNs...

01 March 2021 3,703 3 View

Are protein samples in SDS compatible with ELISA?

I have used an AllPrep DNA/RNA/Protein Mini Kit QIAGEN kit to extract RNA and protein from my samples. At the end of the protein purification, I resuspend my protein in 5% SDS. Will these samples...

28 February 2021 7,370 3 View

How to make fractions of chloroform extract of plant, using seperating funnel?

28 February 2021 8,466 2 View

Why am i not getting solid after reacting APTES with salicylaldehyde?

The reaction of APTES with salicylaldehyde in ethanol leads to the formation of imine compound yellow solid which is mention in literature, but I am not getting yellow solid I don't know why? when...

28 February 2021 2,955 2 View