A few weeks ago I was interviewed for the Chemical Heritage Foundation Distillations Podcast. I spoke about the current state of the Gulf of Mexico after the Deepwater Horizon oil spill. You can listen here.
In December 2010 Katie Sheline ’13 and I were at sea in the Gulf of Mexico examining the impacts of the Deepwater Horizon Disaster oil spill on the seafloor (see earlier posts). When we stepped onboard ship, Katie became very excited and I wasn’t sure why. The smell of simple green? The autonomous underwater vehicle Sentry? The deep submergence vehicle Alvin? The endless delicious food from the Galley? The famous scientists? No, none of these. Even though all of these at some point would provide many exciting moments for us during the cruise, there was a huge grin on Katie’s face for a different reason. Onboard ship accompanying us on our expedition was as Katie put it, “The guy from shark week!” This guy, was Mike DeGruy, filmmaker, underwater adventurer, ocean crusader and as we learned throughout the cruise, amazingly friendly, knowledgeable and all round wonderful human. Sadly, Mike is no longer with us. This is a huge loss for all who knew him and I send my thoughts and condolences to his family. Being at sea with Mike for 10 days, was an incredible experience. I have loved the oceans for as long as I can remember, but his passion for the oceans was infectious and inspiring. I am fortunate to have met Mike. We are all fortunate that he has left us with such beautiful images from the murky depths. You can see more here and hear Mike talk here.
Greetings chemists (and boring people too),
I hope you all have been waiting with bated breath for the past 3 months for this newest blog post. I have been so busy throwing tennis balls at small children by day and sculpting clay figurines of exotic sea creatures by night, that my hands have not been free to type until this morning. Needless to say, we have been productive as ever on the aerosol project in the White lab. Our recent focus has been picking out new sites around the globe from which we can sample aerosol particulate and expand the scope of our project. My ears are quivering with excitement. What pristine, end-member biomes do we have in mind for such an inquiry?
Mordor!
Swamp!
Bryn Mawr!
I finished my work in the lab a couple of weeks ago and definitely enjoyed my time there learning about the applications of chemistry into the field of geology. However, I haven’t been too good about posting, as I’ve had this post drafted for several weeks now. So here it is.
Recently, you may have seen that the fine folks at the Haverford Communications department wrote an article about my internship and I’m going to talk about the sequential iron extraction that was mentioned in the article.
In the Sequential Iron Extraction, we are separating the iron by what mineral phase it is a part of. This allows us to see how much highly-reactive iron (reduced Fe 2+) is present. The ratio of this to the total amount of iron present in the samples, iron tells us whether the ocean was oxic (high in oxygen, like present day) or anoxic. If the ratio is below 0.38, then it is oxic.
If it is anoxic, there are two possible conditions, being euxinic (high in sulfur, similar to the Black Sea today) or ferruginous(iron rich). In this case, we take a ratio of iron as pyrite to highly-reactive iron. We get the amount of pyritic iron from CRS (described in my previous post). If the ratio is below 0.8, then it is ferruginous, which is what we believe data is indicating right now, but we do not have the information about whether it is oxic/anoxic.
This sequential iron extraction has led to “The Case of the Missing Iron”, a tale with a mysterious disappearance of iron from some samples, which is now nowhere to be found.
The extraction method was developed in Simon Poulton’s lab and published in a 2004 paper. There is a specific sequence in which the steps need to be done because later steps also remove the iron associated with the earlier steps. Both Dave and JC, a graduate student in the lab, have run standards in the Poulton lab.
In the procedure, the acetate extraction, requires that it be in a heated water bath, which requires a lot of set-up. Ben Gill, my advisor, had run his own samples to determine if he could just have the samples be spun on a rotator, and found no significant difference. However, Ben, was given the standards to run in Dave’s lab, and was extracting less iron in the acetate step than what Dave and JC had found, even after attempting different methods. Another twist in this tale is that Ben got the same results for the last two steps, meaning that there is some “missing iron” out there. We would usually expect to see the same total amount extracted, with the “missing iron” appearing in a later step.
Samples being spun for an extraction. The picture is sideways.
This summer, I took a couple of days away from lab to collaborate with a couple of artist friends of mine in the Bumpkin Island Art Encampment. With Jesse Kaminsky and Dirk Adams I tried to make visible the broad areas of research that our lab group examines. In particular I focused on exploring ways to visualize source, transport and fate of material in the environment. You can check out photos from the project here. Expect some analysis of the project in the coming months. Happy summer!
This week we packed up the lab and returned to our respective homes.
Katie's home in Georgia
Jenine's home inside of a goblin shark in Brooklyn
Zach's charming suburban NJ home
I write now from the sanctuary of my bed — there is nothing like submerging yourself in blankets to feel at home. No longer will I fall asleep wondering why my ancient apartment mattress is purring. (My theory is that there is a family of raccoons nesting inside of it. Throughout the summer I would occasionally wake up and find that chunks of my hair had been chewed off…)
Raccoons aside, this summer has been a supreme experience and exceeded all expectations, both in the company I had in lab and with the Haverford summer community at large.
The culmination of this summer was our lab retreat to Patrick Lodge in Rothrock State Forest, PA.
Not shown: evangelical christian summer camp next door
When we were not busy fending off bears by using Misha as a human shield, each member of the lab presented a slideshow detailing their goals, methods, data, results, and future directions for their project.
Our fearless leader looks for cell service
In our free time, we made pizza, ate enough snack food to feed a small third world country, and went on a hiking trip which met it’s unfortunate and unspeakable end in a port-a-potty, in a parking lot, in a swamp.
As far as chemistry goes (is that what this blog is about?!), we have made some awesome discoveries in the world of macromolecular organic aerosol material. This includes some exciting evidence for the possibility of aerosol macromolecules coming from marine sediments, a finding we hope to publish alongside the GCMS data we have generated from our sequential degradation.
Here is a picture of something chemistry related to appease Helen:
Sarah removes elemental sulfur from her oxidation extracts with an activated copper column
And on that note I leave you until we return to lab in the fall. In the mean time, stay hydrated, eat popsicles, and ALWAYS keep a roll of toilet paper in your car.
When chemistry goes awry, we see sulfur in places it’s not supposed to be.
When we see sulfur in places it’s not supposed to be, we feel sad.
When we feel sad, we go to the bookstore and buy all of their cheese-flavored snackfood.
Incidentally, this is 3180 calories of food. (We ate all of it)
Eyes glazed over a glaring screen,
Headache pounds and I need caffeine.
How many articles do I have left to read,
My patience does this literature search exceed.
Geochemistry papers seem to multiply,
Scifinder’s sluggishness makes me want to die.
The GCMS is feeling ill once more,
There are chores to be done and morale is poor.
Results are confusing and the data looks bleak,
Solace and comfort food are now what I seek.
Praise the vending machine – my unfailing savior,
Chips in my belly sure do change my behavior.
Food erases the grumpies I had,
Suddenly chemistry doesn’t seem all that bad.
One of the trickiest parts of organic geochemistry is liquid-liquid extraction (or as I have rechristened it, “lick-lick-ex”). The purpose of this procedure is to move gunky organic matter in and out of different solvents depending on whether we want to transport, measure, or react our material. It is finicky, crazy-making work as well as a formidable obstacle in my research. The following comic illustrates my daily struggles:
I. Cloudy solution after RuO4 oxidation, part DCM and part water
II. Adding a few drops of DCM helps separate the mixture into two layers
III. Adding a drop more of DCM warps gravity inside the separatory funnel
IV. Contents of funnel suddenly celebrates marriage laws in the state of New York
V. Extraction goes awry when the sep. funnel bursts into boiling flames of acid
VI. Suddenly the encouraging face of Jesus appears in the depths of the funnel
VII. Finally a drop of water separates the aqueous and organic layers
VIII. Until the funnel shatters when Katie tickles Zach while he holds delicate glassware
I forgot to mention, on the way home from group meeting at Peace a Pizza we picked up some crayons so that we could decorate the lab with beautiful illustrations of our work:
