Recent content by kl055

Hi I have a simple question about HPLC regarding the pore size vs the molecule size of the analyte. Are there cases when it is desirable to have a pore size smaller than the analyte molecule size? In this case, the analyte will be eluted first, then the solvent will be eluted later...

Thanks, I will do that.

Thanks. Is normal filter paper sufficient to resist HCl or should I be buying special "hardened" and/or "ashless" filters?

If the solute is ~100um uniform in size (solid outside of the HCl), shouldn't paper filters work? Would be sufficient to use a pore size of 50um, or should I use a smaller size?

Do I need to worry about the pore size, or can I just assume that any/all paper filter will remove the organic compound while letting the smaller HCl molecules through? The molecular weight of the organic compound is listed as "240"

I get that V_A is given by a voltage divider, but why is R_E in parallel with 1/g_m1?

Homework Statement Why is R_E in parallel with 1/g_m1? I drew the small signal model but it does not make sense to me Homework Equations The Attempt at a Solution

Okay, thanks

I suppose not since there is no C^2. So I need to derive another equation?

Sort of. I had a circle in the impedance plane of the locus diagram. There were two intersections (when only the real part of the impedance exists at resonance) meaning that for a given value of L there were two values of C for which the circuit was resonant. Then I shifted the circle up by...

Sorry, I made a mistake in part 1 of my post. I corrected it now. r = R and the problem is to "Find a value of L and C such that there is only one value of C for which there is a resonant freq" the resonant frequency is given in the problem statement. Using only Locus diagrams and...

Finding L and C for which there is only one resonant frequency in cct Homework Statement an inductor in series with a paralle of (a capacitor and a resistor) The inductor and resistor are fixed while C is variable Z = sL + R/(1+RsC) Find a value of L and C such that there is only one...

I did the derivation and my "intuitive" formula for part 1 was incorrect (by a factor of 3). Part 2 was good but I think that I will derive formulas directly from now on. Thanks for the help

I'll do that. I was just hoping that there was an intuitive way to do it since I'd rather not derive formulas when writing exams unless I have to :S

I'm pretty sure that step 2 is correct. The professor did an example in class that was similar enough to that case. But in step 1, I have input voltage at both OPAMP terminals so I do not know what to do. I'd rather take the OPAMP as a black box with a characteristic equation if possible. In...