is it nessesary to do solution stability for 7 days?

724

My question about gas chromatography sulfur chemiluminsecence detector. I test unknown sample gas by GC-SCD (calibrated ) and the result of *H2S is 279 PPM , *but when I test the same sample with the GC-TCD (calibrated ) the value of *H2S is 2500 PPM . I'd like to inform you that both GCs are calibrated and have very good operation conditions with stable parameters . the question is if the sample gas with higher H2S over detection limits of SCD detector (1000 ppm). why the result it 279 ppm Best regards

1550

what is the procedure for cleaning of lenses of hatr accesory of ftir instrument?

2232

How do we quantify crystaline and amarpous forms by using (NMR, XRD)spectroscopic techniques? Which any others instruments are useful for this quantification? explain

2342

how much mass should be there in volumetric flask while in preparation of sample for assay? 

2518

for inorganic molecules require to do RS, Assay and disso?

679

What is diffrence between extractable volume and deliverable volume? Answer pls

4500

UV and PDA detector, which have less signal to noise ratio?

1087

what is the difference between potentiometric titration and karl fischer titration?

3123

If we have 5 strength which is not dose proportinate and excipients also diffrent in each strength then how we can proceed for Force degradation? and excipient are same but not dose propotinate the how FD?

766

In the HPLC Calibration done wavelength accuracy done between 200nm-280nm .but not done remaining 300-400nm not done ?

862

if identification threshold crosses the limits then what next step?

808

which are the sizes of capsules?

898

why salisylic acid not using now days for disdolution calibration?

717

we can use expired sample for validation and analyst qualification?

752