In DFT or HF, is it more expensive to calculate the H matrix or to diagonalize it?

I was wondering: in common DFT (or Hartree-Fock) algorithms/codes, and in particular in solving the Roothan equation, what is the most computationally expensive part: 1- evaluate all the terms of...

01 February 2021 396 2 View

Warning in Lavaan, variance-covariance not positive definite!, model is not identified?

Dear colleagues, I am new to R, I have been using Amos for conducting CFA but came to learn that when dealing with Likert scale, Lavaan in R is a better tool to do such analysis. I started using...

30 December 2020 5,608 3 View

How can i figure out whether nanoparticles in my synthesis crosslinked or not?

i prepare protein nanoparticles. in one of my synthesis i use trifle amount of crosslinker and the nanoparticles stick in the bottom of plate. how can i understand that nanoparticles become...

03 December 2020 559 8 View

What is the best solver in OpenFOAM to study melt-water interaction?

During a severe accident in a nuclear reactor an energetic molten fuel/coolant interaction could happen, where a multiphase flow of a steam-water mixture in a region which contain drops of a...

29 November 2020 8,376 2 View

How can we define columns in 3D PLAXIS model for buildings existing near the excavation?

I started by a model using 3D PLAXIS to study the effect of deep excavations on existing buildings. The building was simulated as a surface plate with a surface load. Now I'm trying to do it as a...

29 November 2020 3,198 4 View

How to read forces from a file and apply them to a specified nodes in ANSYS APDL?

I want to apply different forces for every node. These force values are saved in .txt or .csv file. Can anybody help me to do that using APDL command. I attached Ansys input file for my model and...

15 November 2020 2,883 1 View

Where can I find off targets for Apis mellifera?

I would like to find off target sites for my sgRNA, however the more commonly used off target finders do not include apis meliifera, is there an application or website that would allow me to do...

09 November 2020 3,463 1 View

What is the best method to sterilize hydroxyapatite nanoparticles?

Powder insoluble

08 November 2020 509 3 View

Wrong cell dimension (cosAB)?

All input files with bravais lattice that contains an angle doesnt run in my Quantum espresso. i even tried running them in my friends laptop but the crash file displays the same problem. i hope...

03 November 2020 2,722 1 View

How Abaqus can generate lumped mass matrix with non zero values only at the diagonal ?

Hi everybody I generated mass matrix by Abaqus, but it has nonzero off diagonal values. I need to get lumped mass matrix with nonzero values only at the diagonal. In Ansys I can turn Lump on...

28 October 2020 5,960 4 View

flexibility of polymers chain

effect of double bond on the flexibility of polymers

07 April 2021 0 0 View

Formulation of polymer color flakes

I am writing to request some information for making polymer color flakes. I would appreciate the help.

17 March 2021 0 0 View

What is the production process of CaFe ferroalloys?

I looking for ferro calcium production process

03 March 2021 1,755 4 View

1. What is the impact of having different scales in a survey? and how can we solve this problem before and after data collection (Literature)?

1. What is the impact of having different scales in a survey? and how can we solve this problem before and after data collection (Literature-based reflection)? Thank you for your time and for...

03 March 2021 2,870 3 View

No title

02 March 2021 3,060 3 View

12% ledeburitic cold work tool steel, etched for revealing retained austenite, any help for clarifying?

Hello everyone. Given microstructure image belongs to a 12% ledeburitic cold work tool steel (annealed and tempered). The sample was etched with picral (100 mL ethanol and 4 g picric acid). I...

02 March 2021 4,119 3 View

Is there any rich, publicly available English literary corpus?

Hi everyone. I am looking for a rich corpus in English literature, a one which includes literary prose ( e.g., novels or short stories) . can anyone propose a good one? Best regards Fatemeh

01 March 2021 1,970 2 View

How does one access the Cranet survey data on HRM practices?

Hello, The Cranet website does not provide any lead to the data obtained from their multinational survey on HRM practices. Any help on accessing the data would be most appreciated. Thank...

01 March 2021 9,536 3 View

How Can I bring as much common elements in steel as possible to calculate stable phase(s) in OpenCalphad?

As I was tweaking step-by-step OpenCalphad6 Macros step1.ocm involving phase and thermal property calculation of a High-speed steel, I could not incorporate more than 6 elements in the steel...

01 March 2021 8,840 1 View

How can you bring two structures together to create an adhesive bond in LAMMPS?

I have created an Ice 1h crystalline structure and an Aluminium substrate structure and equilibrated both at 250K. Now I need to bring them together in a way that an adhesive bond is created....

01 March 2021 3,325 2 View