Recent content by chops369

  1. C

    Understanding the logistics of oncolytic virotherapy

    I have questions about a particular paper: Oncolytic Poxvirus Armed with Fas Ligand Leads to Induction of Cellular Fas Receptor and Selective Viral Replication in FasR Negative Cancer The authors explain that they're using an oncolytic virus to deliver membrane-bound Fas ligand to cells in a...
  2. C

    Henderson-Hasselbalch & phosphate buffers

    Wow. I stared at that problem for 2 hours...I can't believe the answer was right there. Thanks for clearing that up.
  3. C

    Henderson-Hasselbalch & phosphate buffers

    This is an example calculation about the phosphate buffer system from my Biochemistry textbook. Homework Statement If the total cellular concentration of phosphate is 20 mM (millimolar) and the pH is 7.4, the distribution of the major phosphate species is given by pH = pKa + log10...
  4. C

    Approximate uncertainty in area of circle

    I just figured it out. Turns out it was a rounding error on my part, so what I rounded up to 4 * 108 should have actually been rounded down to 3 * 108.
  5. C

    Approximate uncertainty in area of circle

    Homework Statement What is the approximate uncertainty in the area of a circle of radius 5.3 * 104 cm? Express your answer using one significant figure. Homework Equations A = pi*r2 The Attempt at a Solution Using the given radius, I found the area to be 8.8 * 109 cm2. And since...
  6. C

    H NMR of unknown sample (organic chem)

    Yes it was. I would assume that means the signal really has nothing to do with the structure of the sample?
  7. C

    H NMR of unknown sample (organic chem)

    Homework Statement Last week in organic chem lab, we were provided with an H NMR spectrum of an unknown compound with the formula C7H5NO3. I'm not terribly good at analyzing these spectra, but I've managed to figure out that I'm looking at 4-nitrobenzaldehyde. The only thing that's bothering...
  8. C

    Best organic chemistry book?

    I'm no expert on textbooks, but I used Maitland Jones' 4th edition of Organic Chemistry and I found it to be extremely helpful.
  9. C

    Syn versus anti elimination

    My bad. I meant to ask what the syn and anti arrangements favor. My organic textbook says that syn and anti are favored in the E2 reaction over both a 60o dihedral angle and a 120o dihedral angle. This makes sense to me, since these arrangements would require further rotation to make a planar...
  10. C

    Syn versus anti elimination

    Can someone please help me understand the difference between syn and anti elimination in terms of what they favor? My [extremely] limited understanding leads me to believe that syn elimination favors E2 since it mimics frontside attack, which will not work for Sn2 since there is no net-bonding...
  11. C

    Reasons for unusual infrared spectrum?

    Nope, we just put a small crystal into a drop of the oil. Come to think of it, it didn't really look like it dissolved very well. I remember trying to mix it around for a while.
  12. C

    Reasons for unusual infrared spectrum?

    In my organic lab we recently isolated and crystallized the natural product usnic acid from dried lichen. An IR spectrum of the crystals dissolved in mineral oil was obtained, but it came out looking a bit strange. The thing that's really confusing me is that there is no band that would be...
  13. C

    Estimating area with finite sums

    Oh, ok. I see what you're saying about the lengths. So would my midpoints be 7 and 19? What I'm trying to get at is if there's a really easy mathematical way to get the midpoints of these segments. At this point I'm basically being really methodical about it, using my elementary school...
  14. C

    Estimating area with finite sums

    Homework Statement Use the midpoint rule to estimate the area under the graph of f(x) = 7/x and above the graph of f(x) = 0 from [1,25] using two rectangles of equal width. Homework Equations N/A The Attempt at a Solution So first I found \Deltax by using (b-a) / n and got (25 - 1)...
  15. C

    Calc - Derivatives and Differentiation of Logs

    Ok, now I'm stuck again, but only on something minor. I now have 3y2(dy/dx) * ey3 + 2y(dy/dx) = 8x3 If I want to factor out a dy/dx, how can I combine the 3y2 with the ey3 ? Do I just lump them together, i.e. 3y2ey3 ? If so, my original answer was correct for the most part and I am still...
Top