How can I precipitate CdTe/CdS quantum dots from colloidal aqueous solutions?

More Olena Tynkevych's questions See All

SPSS: A scale with multiple items (7-point Likert) across 4 test conditions. How can I correctly summarize it?

Hello, I am currently writing my master thesis where I have a 2x2 factorial design with one downstream variable (2 independent and 2 dependent variables). I need to conduct a multivariate...

11 February 2021 6,014 4 View

Hi, help please, how to cancel the authorship of the article Civilizational Phenomenon of Narcissism: Vectors of Objectification in a Paradigm...?

Hi, help please, how to cancel the authorship of the article Civilizational Phenomenon of Narcissism: Vectors of Objectification in a Paradigm of Psychoanalysis ?

15 December 2019 9,043 3 View

Where I can order fungal ITS1 and ITS4 primers?

I would greatly appreciate for help in the suggestion of company for ITS1 and IT4 primers purchasing in Europe. Thank you.

12 September 2017 469 3 View

Could the gene silencing be avoided when it is expressed from the episomal plasmid?

In the case of yeast transformants

14 March 2016 9,434 1 View

Does anyone know some kits for express diagnostics basic soil characteristics?

Dear colleagues, I need to estimate the basic soil characteristics - total carbon, nitrogen, potassium content. I also need the content of Fe and halogens (F, Cl, maybe I). The point is that I can...

12 February 2015 4,874 9 View

Has anyone used Mesquite for combining molecular and morphological data? Do you know a algorithm for doing that?

Phylogenetic analysis (combining molecular and morphological data).

10 August 2014 4,406 7 View

Could you please suggest a technique of a plant root preparation for XRF confocal imaging?

Zou Finrock and Kelly Summers have recommended me to contact you. We are using 8-day old Arabidopsis plants to see of the effects of toxic metals, in the root tips, in particular. They are really...

01 January 1970 5,600 3 View

What do you think about the status of ownership in the charing economy?

We understand that in sharing economy, access to usage will be important. How will the attitude to ownership and disposal of property change? Do you want be the owners?

01 January 1970 546 8 View

How Relativistic effects is one reason for lanthanide contraction?

The Lanthanide contraction which is the decrease in ionic radii of the elements in the lanthanide series from atomic number 57, lanthanum, to 71, lutetium, is due to poor shielding of the 4f...

01 March 2021 2,272 4 View

Is there a deep reason for using the squared modulus of the wave function as the probability density of the existence of the particle?

I think we were all surprised at the first time we got to know quantum mechanics that the squared modulus of the wave function is the probability density of the existence of the particle? The role...

28 February 2021 6,282 9 View

Why is NH4OH added in heavy metals limit test?

The limit test I'm referring to is USP method II. In this procedure you need to dropwise add 6N of NH4OH to the sample until it the pH is alkali. After that you need to dilute and add HOAc until...

23 February 2021 2,049 3 View

How to predict the reaction pathway for electro organic synthesis?

Can anyone recommend some any software/models available that can predict substance reactivities and the reaction yield under a specific set of reaction conditions process and proposing pathways to...

17 February 2021 2,383 3 View

How complex systems physics/statistical mechanics would be helpful for particle physics & Networking?

Recently, I've been selected for an ICTP program named Physics of Complex Systems. But, I have a keen interest in Particle Physics & Quantum networks. As statistical mechanics involved in...

11 February 2021 699 3 View

Reason for "reading bands namelist error" in band structure calculation in quantum espresso?

At first, I did the scf run then nscf run followed by another run with calculation set to "bands'. And finally, using command bands.x < example.in > example.out to post-process the data, I...

10 February 2021 7,970 2 View

Applications of General Multiple Sums?

Does anyone know of applications of multiple sums of a sequence? I know of the Multiple Zeta values (which is a multiple sum of 1/N^s). This has multiple applications in quantum physics, QED,...

08 February 2021 8,047 12 View

Why it is required to optimize a unit cell generated from cif lattice parameters and atomic coordinates during ab initio solid state calculations?

A cif file represents a unit cell with minimum energy. My question is, in the start of any ab initio calculation for unit cell generated from the cif file, why we are advised to optimize cell...

19 January 2021 9,883 3 View

Why is the calculation of fluorescence quantum yield involves refraction index of the solvent?

Hi why we are using refractive index of solvents when calculating quantum yield in solvent. What is the effect of refractive index to quantum yield?

17 January 2021 8,848 5 View

Are most sol-gel adhesion issues because of surface impurities?

We are trying to get a sol-gel film coating on diecast aluminum/silica (87%/13%) parts, and it is flaking off quite rapidly. This same flaking isn't happening with prototype milled aluminum...

13 January 2021 1,110 4 View

Rafael Abargues López

Dear Olena

Change to acid pH and the QDs will aggregate.

many regards

R. Abargues

Filip Neupauer

I precipitate my CdTe quatum dots with carboxyl groups on the surface by adding isopropanol with QD solution:isopropanol ratio 1:3

Christian Wolff

Rafael has it right, check the isoelectric point of TGA and go slightly below with the pH. Otherwise add a non-solvent like isoprop/ethanol/methanol in vast amounts and centrifuge at quite high speeds.

Another neat trick is to get some molecular weight filters.

Olena Tynkevych

Thanks for the advices!