Why am I getting singlet instead of triplet for my sample?

Both 1H and C13 NMR values of my sample can be assigned to a known molecule except at one place. From reference values and theoretical point of view, a methine proton (CH) near to a methylene...

10 November 2016 2,761 5 View

How do i detect difficult-to-stain saponins in TLC?

The only reagent that I could use to see something is Blood reagent but the handling of this reagent is not as easy as anyother reagents. The fraction of such interest has been tried with spray...

07 August 2016 7,371 3 View

TLC Solvent systems for methanol extract of bark?

Kindly share your experience, if any, with bark phytochemistry. It would be grateful if I get a good tlc mobile phase for studying methanol extracts of bark that is known to contain polyphenols.

08 September 2015 9,600 0 View

How can Soxhlet extraction be explained using a mixture of solvents?

05 June 2015 2,921 8 View

Is there a characteristic C13 peak in the NMR spectra for terpenoids and steroids?

Please tell me if there is any in order to distinguish the spectra of terpenoids and steroids.

04 May 2015 9,644 9 View

Does drying affect vitamin content of plant samples?

Can vitamins be estimated/analyzed from dried samples preferably dried at 40 degree celsius?

01 February 2015 1,744 11 View

Is there any negative impact of diethyl amine while using in column chromatography?

I would like to know if there is any especially while purifying a molecule and also in obtaining NMR spectrum of thus purified molecule. Does the presence of trace DEA or its impurities while...

01 February 2015 4,116 5 View

Has anyone ever used cheaper/small/moderate pressure pumps to increase the flow rate in columns?

I would like to have one for my RP open columns. Please share your experience and thoughts. Also please share what kind of pump you have employed for your work.

31 December 2014 5,521 5 View

Any easy explanatory notes about HMBC?

Looking for good explanatory notes to understand HMBC. Simple explanation with worked problem is also much appreciated.

11 December 2014 2,306 11 View

How do I remove perchloric acid from my samples so that it can be loaded onto HPLC columns?

It would be very helpful for my work if anyone can suggest a way to remove perchloric acid from my sample for further chromatographic studies.

10 November 2014 9,563 3 View

error in running a model in Abaqus

Excessive rotation of nodes in node set ErrNodeExcessRotation-Step1

17 August 2021 0 0 View

error in modelling model in Abaqus

Excessive rotation of nodes in node set ErrNodeExcessRotation-Step1

17 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

MD MOE RMSD

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

07 August 2021 0 0 View

MGL tools

20 June 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

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

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

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

flexibility of polymers chain

effect of double bond on the flexibility of polymers

07 April 2021 0 0 View