Is caffeine a primary standard in analytical chemistry?

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I got 02 moderator values defining Johnson-Neyman significance regions. Is it an error?

Hi everyone, I am conducting research for my Master's thesis. I am using PROCESS by Johnson-Neyman to analyze my Moderator model. I test the relationship between Public Service Motivation and...

03 March 2021 2,350 2 View

How to include original NMR data in a manuscript?

hello. i am junior researcher. I received a comment from a reviewer that he could not find NMR data in my submitted paper. I had included the NMR graph with explanation and formula to calculate...

27 February 2021 734 4 View

What influences inter-day reproducibility in UPLC-MS/MS analysis?

I was analyzing some metabolites in human plasma. While the intraday precision of these metabolites was acceptable ( less than 20%), the interday precision was quite large. So what influences...

13 February 2021 9,183 9 View

Despite single-cell RNA, how can I characterize a new cell subtype/phenotype?

A new cell subtype was found out only during regeneration phases after a cuprizone-induced demyelination model. How can I characterize this cell? It is important to highlight that was already...

13 February 2021 1,245 1 View

Where can I find FDI data by sector/industry for Asian countries like India and China for the last 30 years?

Common databanks like UNCTAD, OECD, WorldBank and ASEAN Website did not have the data for the last 30 years.

09 February 2021 4,701 4 View

Permanent Fluid temperature initialization in Ansys Fluent?

Dear researchers, I am coupling Design Optimization with ANSYS Fluent in Workbench 2020 R2. I can do the analysis. I am patching the initial Temperature values of the zones. However, the patch...

28 January 2021 4,265 2 View

Luciferase assay for miRNA-gene: How to obtain DNA (PCR product) from the mutated primer?

To perform the Luciferase assay for microRNA-gene interaction its necessary a primer (wild-type) to amplificate the specific ligation site and also a mutated primer. But if your primer has a...

19 January 2021 8,568 3 View

How to solve AMPS 1D simulation error?

I am trying to model a photovoltaic device using AMPS-1D software. But once I am submitting it to the queue, it remains there for an infinite amount of time without giving the result. I couldn't...

11 January 2021 9,801 2 View

How to couple Moldex 3D with MATLAB for design optimization of an injection mould?

Hello, I would like to use the software Moldex 3D for the design optimization of an injection mould. How can I couple Moldex 3D with a MATLAB code? Any help appreciated, I wish you all a happy...

09 January 2021 569 2 View

How to setup ANSYS Fluent for simulating the filling stage of an injection mould?

Hello, I am using ANSYS Fluent for simulating the filling stage of an injection mould. However, when comparing the results with those of specialized software, such as Moldex 3D, I found the...

07 January 2021 7,992 1 View

MD MOE RMSD

How to calculate the RMSD values for a MD simulation using MOE?

07 August 2021 0 0 View

MD MOE RMSD

How to calculate the RMSD values for a MD simulation using MOE?

07 August 2021 0 0 View

fatal error

When I tried to energy minimization my system, I got fatal error as below. Fatal error: Atomtype opls_116 not found Although I've already added this line: ; include water #include "oplsaa.ff/spc.itp" to [molecultype] directive in my topology.

16 June 2021 0 0 View

fatal error

16 June 2021 0 0 View

fatal error

16 June 2021 0 0 View

fatal error

16 June 2021 0 0 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

I am interested in medicinal chemistry field, which books are highly recommended to learn from?

I am at the beginner level in drug design and drug discovery, and I am interested to learn more about this field. Which books are highly recommended to start from and gives me all essential...

02 March 2021 8,437 2 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

Marcos Steola

Hi Lucas, Ali is correct, but remember you need know purity of caffeine standard for use in an analytical analysis.

Michael G. Weller

For analytical purposes, it is the best to use a certified reference material, for example https://www.sigmaaldrich.com/catalog/product/sial/56396?lang=de®ion=DE