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

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

Carbon Emission calculation factors ?

I am thinking about writing a paper on carbon emissions based on electricity consumption data from some buildings. From a research perspective, which factors should i specially focus while...

09 October 2020 4,142 3 View

I need to image mesoporous silica nanoparticles that are in ~100 nm size and do high resolution TEM to look at mesopores. what grids should I use?

Need to image mesoporous silica nanoparticles using the TEM. Also, need high resolution TEM images to see the mesoporous structure. Kindly suggest what kind of grids to use. Thanks, Shatadru

02 March 2021 1,787 2 View

Can chitosan alone can act as a reducing agent for Cu(0) nanoparticle sythesis?

[Synthesizing Cu nanoparticles without using chemical reductants]

01 March 2021 8,359 1 View

Timeout error!! Processor in the loop (PIL) using STM32F4 Matlab 2018a?

Dear Researchers I am trying to perform a PIL simulation using STM32F4 Discovery board and comunication serial USB TO TTL. During simulation I receive the following timeout error: An error...

01 March 2021 2,327 1 View

What are the new 2D nanomaterials were used for Silver nanoparticles stabilization?

In the stabilization of AgNPs are vital in current research interest. However, some of the 2D nano-materials like graphene oxide, MoS2, etc... previously used to stabilize it. But still they shown...

01 March 2021 2,207 3 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

How to check the uv-vis absorption of nanoparticle by surface plasmon resonance?

I try to check the uv-vis absorption of Indium nanoparticle. Now I am measuring in solution, can I measure it in the form of a film?

01 March 2021 930 3 View

Distribution of particles in metal matrix?

How would define the "good" and "poor" distribution of particles within the matrix. Is there a quantitative solution to assess the distribution of the particles, which then having denotation of...

28 February 2021 7,397 8 View

How to eliminate Steady state error from Reinforcement learning genetic algorithm code?

The following code (see 1st 2 images attached) is used to produce PID controller values that are designed to control the system (G). The code finds the PID controller values (noted as k) by using...

28 February 2021 6,560 14 View

How can I calculate the rdf of water molecules around 'Na' ions that are closest(adsorbed) to the nanoparticle(solute)?

Hi, I want to calculate the radial distribution function for water molecules around the Na+ ions adsorbed on the surface of a spherical nanoparticle using the gromacs trajectory dynamically? For...

28 February 2021 5,650 1 View

How to prevent ANFIS Model from negative prediction values in MATLAB?

I have input and output data set for "ANFIS modeling in MATLAB", and I am getting some negative predicted values of output in testing. However, the predicted values of output in training are...

28 February 2021 3,459 3 View