QUADRUPOLE

[@bratwurst5267]

Thank you for the video! Very helpful. At the end around 10:44 you should swap the description "do pass" and "do not pass" because like this it looks like a small window of m/z does not pass. But this is a small mistake in an otherwise very helpful video.

[@TheFormigalformigal]

There is a mistake in the graph at 10:30. The Y edge is wrong. The label "Do pass" should be "Don't pass" and vice versa.

[@haubentaucher8382]

As far as I understand the X-dimensions switch should be shifted more to thr right and the Y-dimensions more to the left, so there is a small overlap. Flipping one of the dimensions would render the flipped one meaningless.

[@codchemistryclub4358]

No, it is correct as written. There are two voltages applied, + and -. Ions that are small WILL pass the first, (so their line is high), but they stop passing at a certain point (drops to the baseline). Large m/z will NOT pass the -DC rods, so they are at baseline (do not pass) and shoot up to "do pass" for +DC. The gap in the middle is the range of m/z of ions that will pass BOTH. The lines only represent the sizes that do or not pass each step. the correct size ions would be a 3rd color, at the top I suppose. The idea is to highlight the narrow window of sizes that will work, not show a line for them.

[@prapsdy]

at 11:34... shouldn't the do pass lines overlap? red line fitler is barring all the molecules that green line filter is allowing and vice versa.

[@apiitg]

You are correct. There is a mistake in that graph. They should have a narrow overlap for m/z to pass.

[@Huangbeibei]

I agree

[@DP-vm2dd]

hi! at 4:04 the potential should not start from 0, because the radiofrequence voltage is V* (cos freq. *t). So it should start with a positive value. is it ri ght?

[@dkreller01]

Yes, I will admit that the explanation is perhaps a bit too qualitative. When I posted I was expecting that there was a weakness there. However, I had a good time trying to explain this, and I am glad if this video helped you in your studies.

[@sammyk1155]

Very nice video Dr Keller, very helpful

[@lorenzwirth]

Thank you very much! Nicely explained, I finally understood.

[@lisaghosh3966]

Excellent! Very informative. 👍👍

[@simonagidova8856]

Thank you from all videos about quadrupole this is the best for understanding😊😊helped much

[@parniunplugged7023]

very nice explanation for beginners.. Thank you very much

[@MrElectricSkittles]

excellent finishing diagram

[@lucnegroni2045]

super bien expliqué, merci Great, thanks a lot

[@neeleshukla]

Very helpful in understanding the working principle of quadrupole.

[@29Valle12]

thanks!I found it very helpful and clear

[@matteopiccioni196]

Great explation..but how can a rod produce both a sinusoidal and constant potential?I also saw the electrical configuration of the genertors..but I'm used to think about than electrons flux are in movement or stationary....it is killing my mind

[@sammyk1155]

A DC voltage and an ac voltage are combined together. So if the DC is say +1 volt and the ac is 1 volt peak to peak it would be like the ac wave was raised 1 volt on the graph, so y=sin(X) becomes y=sin(X) + 1

[@Nellaitamilselvan]

I don't understand a point. How do you apply a RF in DC rod?

[@debanjankar6811]

The ions produced by MALDI can be analysed by TOF but not by Q, whereas ESI can be fitted with the second one. Why?

[@ThomasHaberkorn]

A basic question: how is charge related to mass and in general how does the ion source work?

[@fatemehrajabi2830]

IS this application of magnetic quadrupole?

[@yonatansmn]

what happens to the ion after it crashes?

[@Ed-uz1xw]

The charge is electrically neutralized, at which point the ion is no longer charged. It is then removed by the vacuum system.

[@zhongpingliao3574]

Very helpful vedio for understanding how DCand RF is used to select ions by the four rods. The only mistakes the m/z selection of the two dimentions (X, Y) should be overlapped in order to have a narrow m/z pass through the rods. Otherwise, no ion will pass through.

[@kimtran7045]

thank you very much

[@xuan-lc5vy]

Please let me know, compare the cost of icp-ms quadrupole, flight time, multicollector magnetic sector. thank

[@johnnyzt]

the 5:00 explanation is a mess.

[@fadukhan1697]

Aloha I have Varian 820 ICP MS and have some issues. Can some one help?

[@ThePtgautam]

i liked it

[@mimizizi2373]

Thanks