Monday, December 24, 2012

Nuthatches & Crossbills

This post is about a serendipitous walk through Greenlawn Cemetery in Columbus, OH.  You may be wondering why I would be visiting a cemetery where no one I know is buried.  The reason was because we wanted to catch a glimpse of some white-winged crossbills which had been hanging out there for a few months.  Ben's family is from Columbus and I'm visiting for Christmas, so yesterday we all went out to the cemetery in hopes of seeing a crossbill.  The first 45 minutes or so we didn't see much.  It was cold and had just snowed a few days ago, but fortunately the sun was out.  After a while, we caught up with a winter flock of chickadees, cardinals, and juncos chattering in the thickets.  No crossbills yet, even though we were surrounded by spruce trees laden with cones.  Then Ben and Bob, his stepdad, decided to check out a red oak because the leaves on the ground looked interesting.  Out of nowhere, several nuthatches (at least 3, 1 red-breasted and at least 2 white-breasted) popped up and starting foraging all over the boughs of the oak.  It was awesome!  Mainly because the red-breasted nuthatch has eluded me since this summer when Ben and I were hiking around Long Island and I kept hearing them honking way up in the treetops, but never caught a glimpse of one.  I did see a white-breasted nuthatch on LI though.  Nuthatches are tiny, interesting, hyperactive birds that climb all over tree trunks and branches while foraging.  They also make incredibly loud and distinctive noises despite their tiny size. 

Seeing these nuthatches in full sunlight, on a leafless winter tree, and together on the same tree climbing around and emitting tiny yelps was such a cool experience.  But then things got even better, because after we left that tree we came across a group of white-winged crossbills eating snow from a crack in another tree!

(Photo by Ben)
We watched the crossbills for a while as they flew up into some sweetgums and started eating the ball fruits.  Finally a few did fly over to the spruces and we actually saw them eat the cones, which was neat.
Male white-winged crossbill foraging.

House finch

A very cold-looking junco
Red-bellied woodpecker

Red-bellied woodpecker where you can kind of see the red splotch on its belly

Yellow-bellied sapsucker

Friday, November 16, 2012

Katydids on dead trees

Some old pictures from a weekend trip Ben and I took up to Balcones Canyonlands (the "hill country" around Austin, TX) back in late June.  We really wanted to see a black-capped vireo, but it was getting late in the season.  We did hear one beez-beezying in the brush though.

Western kingbird and a baby

Some skinky dude.

A lark sparrow.

Sunday, November 11, 2012

Plant and bird sketches

A couple drawings I made with markers and pen:

White throated sparrow with bog plants (sundew, butterwort, pitcher plants)

Black-capped vireo with passionflower. 

Thursday, November 8, 2012

Shrews and bats

Today I listened to a talk by a mammal paleontologist about high-resolution stratigraphic records using mammal fossils from the Bighorn Basin, WY.  The talk of pygmy hippos reminded me of a really neat exhibit in the American Museum of Natural History in NY:

Sunday, October 28, 2012

The final Hf column, and my last few days in Lyon

The past week has been a bit of a whirlwind.  We learned that Janne Blichert-Toft (my supervisor here in Lyon) will have to undergo some pretty serious surgery, which will mean she will be out of the lab all of November.  So that means I am coming home early.  Despite this bad news, we managed to finish all my hafnium chemistry last week, as well as finish dissolving another sample (the kelyphitized garnet separate that will replace the "pure" garnet separate we lost early on after difficulty with the bombs).  So, one last look at our scheme:

So now, my Hf fraction is ready to go on the mass spectrometer!  The only other chemistry left to do is the separation of the REE.

To pick up where we left off from Column "1".  After Column "1", we're left with our sample stripped of everything else except for Hf, Zr, and Ti.  In Column "1", a dilute solution of HF and HCl was used so that Hf, Zr, and Ti "stuck" onto the resin (via complexation with the F- in HF.  Amazingly, the F- is so strong that this works even in such a dilute solution!).  While those elements were sticking on to the resin, all the other elements were stripped away.  Finally, to remove the stuck Hf, Zr, and Ti, we eluted with a stronger concentration of HCl (6 M).

So, at this point, all we have left to do is remove Ti, which is what Column "2" is for.  Column "2" is by far the most spectacular looking (IF everything in the previous 2 columns went perfectly!).  The reason is because the very first step of Column "2" is the addition of a small amount of H2O2 to the sample.  H2O2 complexes with the high field strength elements.  All the complexes are colorless, with the exception of the Ti complex - this one is bright orange-red.  We definitely had a highly nervous moment when we added the H2O2 to my samples (everyone in the lab watched) - because if nothing turned red, that means the Hf and Ti got lost somehow earlier.  Thankfully, all the samples did change color, meaning all the previous columns ran fine.  Below, here's the sample + H2O2 loaded onto the column.  You can see the bright red bands that represent Ti:

Below, here are two subsequent photos of the column being run.  So cool how you can watch the Ti (well, watch it very slowly... the narrowness of this column means it takes ~1 hour or more for each elution step):

So, that was it.  All hafnium chemistry done.  The final thing I did was then to evaporate the Hf separates.  So there's about 6 ml of solution at the final step, and after it was completely dried down, all that was left was literally a SPECK in the bottom of the beaker.  That speck is all the Hf and Zr contained in the sample (well, not exactly 100%, but we're hoping at least 90%).  That was definitely a cool moment - after three columns, all we have left is a few black specks.

One thing I have learned about column chemistry is that it can be tedious and take a long time.  Particularly when you re-use columns (which is a good thing, because resin is very expensive).  Re-using columns means they must be cleaned exceptionally well, which is often a whole-day affair, if not more.  I'm amazed by the amount of acid we have gone through in running columns and cleaning them.  With three people running Hf chemistry in the lab, we've probably gone through a liter of HF just in cleaning columns, and more for HCl.  And that's just in 3 weeks.  At one point, we ran out of acid and had to wait a few days for it to be distilled.  Then after distillation, it has to be titrated - which in itself can take an entire afternoon.  Then there is the continual washing and cleaning of beakers so that everyone has enough stuff to use.  It's definitely a lot of work to run and maintain an isotope geochemistry lab!

That was a bit of a stressful week, but the nice thing is now I have a couple days to see as much more of Lyon as possible.  Unfortunately the weather took a nasty turn here:  temperatures around 35 F, rainy, and with a biting wind.  Of course, that has to happen the last few days I am here, while all of October was wonderfully pleasant and anomalously warm.  I wonder if this sudden change to freezing weather has something to do with Hurricane Sandy moving along the Eastern US Seaboard.  The North Atlantic was unusually warm this year, with sea surface temperatures over 2 degrees above average.  These anomalously warm waters are probably what's feeding the hurricane and allowing it to intensify.  Western intensification at its most intense?  While the hurricane is sucking up all that warmth, the eastern side of the ocean basin (Europe) isn't getting any more of that warmth, and instead is now freezing (intensification of what would normally happen for cold eastern boundary currents).  Anyway, as I write this, I can hear the wind roaring outside and I even had to turn the heat on.

So the bad weather is keeping me indoors for now, and giving me some time to work on some job applications.  My brain is kind of dead after this crazy week, so I just decided to work on "easier" stuff like applications, and to relax a bit.  I feel like this whole month has been intense.  With the nature of my samples being so rare and precious (in the sense that it took 5 months to glean enough sample), every step in the lab had to be orchestrated perfectly.  And some parts were pretty dicey.  A few samples behaved really oddly, like being strangely viscous and forming a gel at the bottom of the bomb.  We then had to stick those back into the oven for several more days until a homogenous solution was obtained.  One sample even got stuck in the resin while we were running one of the columns, and lagged behind all the other samples (which meant waiting till late in the evening for it to go through, and hoping it would!).  So, I will be amazed if at the end, we actually get a meaningful number out of all this!  Even if we don't, I still walked away with an invaluable experience.

While being cooped up inside last night, I decided to finally do some drawing.  I used to draw a lot, and took several art classes in college, and have always drawn for fun.  I find it a stress reliever - to be able to concentrate on something that just requires hand-eye-brain coordination and nothing intellectual.  But I literally have not had time to draw anything serious in months, probably years.  Thankfully I still carry around these thin colored pens with me, just in the random event I feel like drawing something.  You can get these at any art supply store or even Staples and Officemax - they're Triplus fineliners, made by Staedtler.  Pretty inexpensive, and highly portable.  I drew two birds I've seen here in France, the blue tit and European robin:

And then I decided to do something more complicated, one of my favorite American birds, the American kestrel:

Sunday, October 21, 2012

A walk in the Parc de la Tete d'Or

Yesterday, the weather was incredibly warm (mid 70's), and it was actually sunny and clear.  The weather in Lyon is really mercurial.  One day, it will be cold, rainy, and foggy, the next (or even in the latter part of the same day), all of that will blow away and the sun will come out.  Since it was Saturday, and nice out, I decided to go up to the Parc de la Tete d'Or.  I had been there one time before a couple weeks ago, but the weather was pretty bad so I didn't stay long.  This time I got to see more of the park, and some new birds too!  Those include little grebe, black-headed gull, greylag goose (I think that's what those were, but the bird book says I shouldn't be seeing them around here right now... so maybe they're something else, or domesticated), coal tit, blue tit, and my favorite one, the European robin.  I didn't bring my DSLR with me, so I just had binoculars and a small point & shoot camera.  Amazingly, this little robin hopped out right in front of me as I was approaching to examine something on a tree.  It paused long enough for me to actually get a somewhat decent photo (on a camera that has like 4x zoom).  It was cool to watch them, they're shy bird but they will occasionally hop out right into the open and sort of look at you quizzically. 

I was inspired to draw one.  For some reason, I serendipitously had a pen that was almost the exact orange of the robin!

Some more photos from the park:

This is the incredibly ornate front gate to the park. 

I thought this was a cool play on "Lyon".

Greylag goose? Also some lovely autumn colors.  Nice to experience a real fall again.

Reminds me of burr oak acorns, must be some Eurasian Quercus.

Sycamore tree bark.  Or maybe it's London plane tree - how does one tell the difference?

A magpie in a tree ablaze with autumn colors. 

Thursday, October 18, 2012

Column chemistry

It's been a productive week in the lab.  On Monday, I observed the Nu Plasma 54 mass spectrometer in action, on Wednesday I ran the second round of Column "0", and today I ran Column "1".  Running Column "0" twice is necessary for samples >300 mg (most of my samples are around 600 mg), due to the limited capacity of the column.  Columns "1" and "2" don't have to be run twice, though, which is nice.  So here's the cartoon again, updated:

After running Column "0" twice, we have collected all the Hf separate (which goes on to Columns "1" and "2" to purify Hf) and the REE separate (which goes on to extraction chromatography to separate individual REE, to be done later, after Hf chemistry).  Of course, the "Hf separate" obviously doesn't just contain Hf (or else we would be done!), but contains Ti (which we need to eradicate via Column "2"), Zr (which we fortuitously don't need to worry about because there isn't a mass interference), and some other elements, such as W (which we do need to worry about, as W 180 interferes on Hf 180, even more important because our spike is Hf 180), and Ta (and probably Nb).  After running Column "1", all we will be left with is Hf, Zr, and Ti.  Column "2" will then take care of Ti, leaving us with just Hf and Zr (and I just told you Zr is OK to have together with Hf).

In contrast to Column "0", Column "1" is an anion-exchange column.  This means that anions (negatively charged ions) will adhere ("stick") onto the resin.  We first take up the sample in 1 ml of 0.5 M HF:0.5 M HCl, do the necessary heating, ultrasonicating, and centrifuging, then load the sample onto the resin.  Next, we elute with this same acid combination (0.5 M HF:0.5 M HCl).  Note this is a pretty dilute acid.  In such a dilute acid, Hf will complex with the F- ion in HF, forming an anion complex that will stick to our resin.  However, all the other elements will fortunately not complex with F-, and will thus be eluted.  So how do we get that Hf (and Zr and Ti) out?  We next elute with a stronger acid, 6 M HCl, which is strong enough to strip away the complexed Hf on the resin.  This is what we collect at the final step, and which will go on to the final column (Column "2") to remove Ti leaving behind just Hf and Zr.

Here's a picture of Column "1".  It's a smaller column that "0", but with a wider resin bed diameter, meaning that care must be taken while loading sample and acids in order to not disturb the resin.

Unfortunately no cool colored band representing an element within the resin in this one.

After we've collected our Hf, Zr, and Ti in clean teflon beakers, the next step is to add ~10 drops (1 drop ~ 30 ul) of perchloric acid, and then we evaporate on a hot plate, but NOT to complete dryness.  If everything gets evaporated, an insoluble precipitate will form and you'll have to re-dissolve it all over again using HF.  We don't want HF on the next column (Column "2"), because if we had HF on this column, it will just strip all the Hf away.  So we are faced with the delicate task of keeping Hf in solution, which means not forming a precipitate, before we can run the next column.  This is done by evaporating with perchloric and leaving a small drop behind in the beaker.  If a precipitate does form (or even if it doesn't and you want to pre-empt one from forming), add 2 drops of HF to keep Hf in solution.  Then when ready to run Column "2", evaporate a little to remove as much of that HF as possible.

Next week, I'll run Column "3".  Till then. 

Sunday, October 14, 2012

Photos of Lyon

I can't believe I've been in Lyon for 3 weeks!  It's definitely flown by.  Some pictures of things around town:

Statues in Parc de la TĂȘte d'Or at the northern end of the city.

Main square in Bellecour

One of the many bridges that cross the Rhone and Saone rivers and that you can walk across.

Chickens from the famous Bresse regions (which is famous for chickens) at Les Halles de Lyon, an indoor market.

Porcini mushrooms.  October is wild mushroom season!


This looks suspiciously like chard, right in the middle of the park!

Queen for a night in the most elaborate chair I've ever sat in at La Comptoir de la Bourse.

Yes, I went to Starbucks in France... :-P  I missed American-style brewed coffee and American-style huge mugs :-)