Week 9 Post 2 -PK

Lahh only 3 more days!~ I'm so excited yet sad. I'm excited because I'm almost done with all of my trials. I'm sad because, well I'm almost done working in Shaevitz's lab. Hahahaaa I mixed feelings seem very weird when explaining them.

So everything I've done up till now essentially was just gathering data. I haven't had any time to analyze it really. I did a little bit in July I think, but while I'm in school. I have to do that. So I still have yet to download the software for analyzing and plotting the data. That always seems like it's a problem huh? The truth is I'm technically not supposed to get ANY software since all of it belongs to Princeton and I'm not a student. As I mentioned in a previous post, I am a "visitor". If I didn't make it clear in my other post, I'm very sad. I get the same status of a 1-day visitor despite working in a lab for 10 weeks, walking in and out of signs that say "restricted access" (or something like that), and walking through doors that require a swipe of a key card! Plus, when I buy food from the campus center, I get charged tax :'(
So coming back from my digression, I will be getting the program I use for analyzing the data on Monday. On  Tuesday, I learn how to use it. On Wednesday, I use it a bit and ask Teuta a lot of questions. Then for the next month, I'm supposed to plot, analyze, and interpret the data all by myself. Hopefully I'll be able to come to the lab during some days in September to get help, but the vast majority of it is going to be done by myself. Truthfully, this is going to be a huge challenge for me. One because I don't know statistics very well. Two, I don't know biology very well, so I may not have the best interpretations. Three, essentially I have to teach myself this program. Four, I have a bunch of other stuff going on in September that I'm supposed to do.

But so far, I think I'm going to be getting enough data to be meaningful. Data is data, but meaningful data is better. We'll see. Only 3 days left and nothing major broken. I'm keeping my fingers crossed, but we'll see.

Oh and apparently someone in the lab is working with Cholera so now whenever he's in the lab, I have to wear a lab coat. No one else does... just me :(

Peace~

-PK

Week 9 Post 1 -PK

OMGSH!~ I only have 1.5 weeks (ish) left! Overall the experience was pretty cool, but there are so many things I still want/need to do! Largh, why is there ALWAYS too little time? Well I guess part of the reason is that I'm limited by the number of trials I can do each day. Since I have to grow the E. coli that day, I can only run two trials, regardless of how fast I am at running the actual experiment. Pity...


So I just got back from my two week Bible camp retreat and I was told that once again, I am going to be doing a slightly different experiment. I still am studying the effects of osmotic shocks on the same strains of bacteria; however, I am going to be looking at a different mechanism the E. coli employ when coping with the osmotic shock. The first mechanism I studied was that certain pumps transferred materials (it depends on which pump one is looking at) in and out of the cell. The mechanism I am beginning to study now is the synthesis of materials, one of which is trehalose.


This is going to be pretty awesome, but there are two downsides of this. One, I don't get as much data on the first mechanism as I would be able to if I concentrated all my efforts on the first mechanism. Two, I have to read a lot more primary articles. It's not really that I mind the second one, but I'd really like to keep my brain fresh for the Peddie homework and college apps I do at night. (Yeah... I've been procrastinating a lot lately :( )


I can't wait for the next two weeks to come. Not just because I'm done, but I finally will feel like I accomplished a lot. Hopefully, it won't end and I'll be able to come to the lab during the school year. I don't know how that'll work out, but I got my fingers crossed that it does.


Peace~


PK

Week 4 Post 2

Since the only canister which had 1/4'' tubing was the sample that was suppose to have atmospheric argon, we tested this one first (all the plumbing we had done was with 1/4'' tubing, for all the other ones we'll probably have to use a union which will connect 3/8'' tubing too 1/4'' tubing). We connected the atmospheric argon canister to our new contraption, which allowed us to pump down on the system, and use the mass specrometer without taking either one off. So one all our piping was leak checked and vacuumed, we started the mass specrometer. This was by far the coolest part of the week, where we got to see some real results. We opened the canister valve which allowed the gas to diffuse through our plumping and then we closed off the canister so we wouldn't lose any more gas.

The gas we wanted to sample using the RGA was in our tubing lines so we first checked the pressure which we had conveniently hooked up within the tubing. Unfortunately, their was only about 4 inches of mercury absolute in the entire canister. This meant we wouldn't have much to sample using the RGA, but we used what we had. With the atmospheric argon trapped between two valves and an RGA port connected between them as well, we began to feed the RGA the argon gas which we hoped was truly atmospheric argon.

Returning to what exactly we were sampling for...

The idea is that primordial gases found in the sun were the first gases on Earth. These gases contained Argon in specific isotopic ratio. Primordial gases contained negligible amounts of the Argon-40 isotope. The early gases are thought to have degassed from the center of the Earth into the atmosphere. The Argon-40 to Argon-36 ratio of atmospheric is supposed to be around 295. This high amount of Argon-40 is attributed to different things that I will probably discuss later. This isotopic ratio changes significantly in the crust, and mantle regions of Earth. Based on this, we can try to draw some connections between the origins of our planet, and what it is composed of. Note: This project is also connected to the Dark Matter project, but has opened up a whole new area to us and it is intriguing to see what we are able to find. This connection, I will discuss in a later post after I discuss it more thoroughly with Geoffrey.

Back to the results. The isotopic ratio of Argon-40 to Argon-36 observed was around 300, which confirms that the first sample canister was indeed atmospheric argon. This sets a good baseline for the rest of our experiments. Since we know that the system worked this time, it gives us more confidence with future results. I am currently on a family trip and will not be back in lab until Wednesday, August 17.

Last Day- Alec Mitchell

So, this will be my last post on the blog. The five weeks I spent at the Owen lab felt a lot shorter than they really were.

Since it was my last day and there was an undergraduate student leaving as well, everybody still in the lab (including the PI) went out for ice cream as a last day party.

In the end my project was what I originally had planned on. Of course, after working on it I know a lot more than before (and I mean a LOT). I've learned what goes into the process of making a film of quantum dots from synthesizing the dots themselves to chlorinating them to cleaning them to actually spinning them to testing them. To summarize my project, I tested a series of washes on the films to find the best process to make them.

While I spent most of my time working on my own project, I also got to do so many other things including: learning about the projects of the others in the lab, going to lectures, helping put together a glove box, learning how a lab is managed and the different positions in it, and what goes into research.

My two favorite parts of working in the Owen lab were:

1. The research. The lab is an organometallic lab. I never really considered this type of chemistry before, but I really enjoyed all of the work that they do. While the research they do is really cool, this kind of chemistry is extremely dangerous, so being careful is a must.

2. The people. I don't think my lab experience could have  been so amazing without the help of everyone in the Owen lab. I never had any problems asking for help, and someone was always willing to explain things to me. This especially applies to my grad student Zak, who took the time to teach me everything I needed to know and beyond as well as looking after me all the time.

As a final note, I just wanted to thank all of the members of the Owen group, especially professor Owen himself for letting me work in the lab and for making it such a great experience. I wish I could of stayed longer, but I will never forget the amazing time I had.

That's all,
Alec

Week 5 part 1- Alec Mitchell

Now that my final day is coming, I finally realized how much work I still have to finish.

Today was mostly spent finishing all of my films and recovering quantum dots. Tomorrow will be the final testing. Basically I am going to wash the films with different solutions to determine which would make the best film for solar cells.

A good amount of this week was spent creating a good solution of dots to spin from. I finally got that done today, so it all comes down to the final testing tomorrow.

Also this week: Dr. Peretz came to visit the lab. After showing her around, I got to show her how we spin films in the glove box.

After saying goodbye to one of undergrads who doesn't work on Fridays (my fellow unpaid minion), I realized how much I'm going to miss working in the lab (despite how cheesy that sounds). Well I'll save the final reflections for tomorrow.

-Alec

Last Entry (Rotimi Opeke)

I'm home now.

I just finished my lab work on Friday and I was able to pull some 3D images of the surfaces I looked at under the microscope. Have a look.

Now that I'm in Nigeria I will finish up the lab report and my paper as a whole. In terms of applied uses and a better understanding of what exactly an "active layer" looks like, check out the link to this article. The "active layer" is the highly transparent film that is on the piece of glass that the hand is holding.

Ala Viva and thanks for reading

http://www.engadget.com/2011/08/11/photovoltaic-polarizers-could-make-self-charging-smartphone-drea/

Week 4 Post 1

At long last, the second project is complete. We have moved the helium from the 150cc canister to the 4 inch tubing and are getting ready to ship it. There are very specific procedures we have to follow in order to ship it so we are waiting for a response from the shipping team at Princeton who will give us the proper procedure. Until then we have shut the valves on both ends of the 4 inch tubing and taped it up so they cannot be opened. The project comes to close.

The underground argon samples from New Mexico, Colorado, and the Helium Reserve. So we opened up the large metal container that held all the samples. Of course, we weren't sure at first what was inside considering it had no labels. So Dr. Calaprice helped us out because he had experience with the container. We didn't want any mishaps. Inside of the large metal container were smaller metal contraptions that held different samples of argon gas from the above mentioned areas. We planned how we wanted to sample each one of these smaller canisters and have to build new plumbing for it. In the next few days we will start sampling each one. We started the construction, but it isn't complete so I will describe it in the next post.

Week 3 Post 2

The calculations which were necessary to make the entire procedure possible were nothing over the top, but instead an application of one of the most fundamental, and important formulas that relates gases: PV=nRT. By manipulating this formula, then finding the inside diameter of the copper tubing, we were able to create a formula which had only one variable, which was length of the copper wire. Trying to get as small as possible, without being too hard to work with, the optimal choice of length was 4 inches. So the process began... we attached two of the best valves we could find to either end of the 4 inch tubing and connected the whole thing to the original system we used to fill the 150cc canister. Luckily, we had filled the 150cc canister with 20psig of gas meaning we had enough purified helium in the canister to fill the 4 inch tube. So the canister was attached at the other end of the 4 inch tubing and valved off so we could safely pump and purge the 4 inch tubing. We did all the plumbing with of the copper lines, and finally got it all set. We hooked up the pump and leak checked the whole system. We wanted to purge the whole system with purified helium a few times to ensure that there was no air contamination in our 4 inch tube. So we passed some additional underground gas through the zeolite and passed this purified helium through the 4 inch tube 3 times. Once we finished pumping and purging. We pumped down one final time and on Monday we will move the helium from the 150cc canister into the 4 inch tubing.

Week 4 posts 1 & 2

After some posting difficulties, I bring to you a double feature post.

This week has been a significant learning experience. I've run into several problems during the course of my project, and that doesn't help the already shortening schedule. Of course a little bit of patience and a lot of help from my grad student goes a long way.

After running the Cd:Se ratio reactions, we concluded that it didn't make a huge difference. Instead, we want to up the Selenium side of the ratio now. As before, we still want to find the best concentration for making quantum dots so that we get more than 3g of dots from a 2L reaction (that's a ridiculously small amount). The 10x concentration reaction didn't work, but we'll try 5x on Monday.

Also on the agenda this week was building, testing, and photographing transistors. Everything went fine until the testing because all of the semiconductor analyzers are at least 20-30 years old and enjoy crashing frequently. We did discover that a 2 molar CdSe spun film cracks, so the concentration has to be lower to build solar cells.

While recovering dots that spun off of the films this week, we found that the aluminum foil that's been used to collect the dots has been reacting with them. Why's that a problem? When it reacts, it makes the dots impossible to clean (we haven't tried everything, but it seems like a lost cause).

The more positive parts of this week were:

1. After chlorination, I got some new dots ready to spin a whole series of 24 films next week. (that series will be about finding the best process of making a film.)
2. I've started working on a presentation that will become my poster.

To be honest, I really wish that next week wasn't my last. I was talking to one of the grad students in the lab and we agreed that it barely felt like I was there for a month. Just another reason to make my last week the best one yet!

-Alec

Week 3 Post 1

After contacting Sujoy, the Harvard geochemist whom we needed to send the helium sample to, he mentioned to us that we needed to directly reduce the amount of gas we had. The 150 cc (cc= ml) metal canister had to much gas and was too much for his very sensitive RGA to test. He said we needed to reduce the amount by a factor of 3-4 in magnitude. That is a very small amount of gas to trap using canisters. Geoffrey thought of the clever idea to trap this small amount of gas in between the copper lines instead of trying to reduce the pressure in the 150cc canister. This also meant we had to carefully purge the copper lines we wanted to send and also valve off the ends with the best valves we could find to reduce any sort of leakage. Because we had to wait for a response planning this procedure took us to the middle of the week.

Sleep is for the weak (Rotimi Opeke Week 7?)

Hey guys!

This is my last week! I can't describe how happy I am to be finishing up this week and heading back home to Nigeria. All though I have lots of work to do when I get back home (college applications, Convocation speech, summer homework and SAT prep), I'll finally be reunited with family....but until then....

This week I have finally started the analysis. For 10 hours on  Monday, I prepared my own organic solar devices for the first time and was able to perform electrical characteristics (I finished it all before midnight!). My devices worked perfectly and gave me the data that I need, so I am really proud of that and it makes my job in analysis a lot easier. Although the graphic extensions in Excel leave much to be desired, I can get enough from the program to analyze my results fully (Power Conversion Efficiencies, Fill Factor, etc.)

Today was my morphology testing and it was a much shorter day. I prepared my mini-samples for the AFM (Atomic Force Microscope) in the advanced instrument building and have been measuring the surface geography of these samples for the past 2 hours. The scanning is really slow and takes about 15 minutes for each image, but I don't mind staying a bit later to get all of my work out of the way.

Tomorrow looks like it is going to a day full of teaching as I need to pass on my knowledge to a visiting researcher before I leave the US on Saturday. Because I developed all of my methods by myself and have used very little help from established literature, I need to pass on my knowledge to another person in the lab to continue as I prepare to go back to school.

Ala Viva.

Week 8 Post 1 --PK

It's great to be back in the lab!... well sort of. I definitely don't miss the delectable aroma of E. coli. But it's nice to work with awesome equipment and know that you're doing something actually productive and brand new.

So, after my break from the lab, I returned today to find out that the next three weeks are going to be extremely  busy for me. So basically I have been running one 3+ hour experiment every day. I've done that for three different E. coli strains for different magnitudes of osmotic shocks. Now, I have to run 6-9 20 minute experiments AND the one 3+ hour experiment every day. It's a lot harder to increase my output by 600-900%! However, it should definitely  be worthwhile since I'll be able to collect a ton of data.

Sadly, I only ran one experiment today. :( This was due to technical difficulties with the optical trap. It took more than two hours to fix and recalibrate. Also, I made a few errors in the slides I prepared. Good thing I have 3 more weeks to practice.

Also, I finally got the installation CDs for a program I need to analyze the data. So hopefully, I won't be needing to analyze everything in Matlab. Matlab is really convenient for data in matrices, but it's a bit tedious and annoying to put the data into the correct format and laying it out as graphs or other such things. The program I will be using is called Labview. I'm pretty sure I won't need to learn another programming language, which is a bit nice. So towards the end of August, I'll be analyzing data while running experiments. So I'll be SUPER busy. Can't wait... seriously.

Also, I'm very happy to say that so far, I haven't broken anything despite the fact that I am constantly rushing around trying to get the timing of my experiment perfect. The problem is that timing the growth of E. coli is hard since they are living organisms and grow at slightly different rates (even if they part of the same colony and strain).

Can't wait to finish! I'll try to keep you, the general public, updated on my most current activities, but it might be hard since I literally will be working 9.5 hours a day with only a 30 minute break for lunch. :( I like breaks.

Peace~

-PK

End of Week 3 - Alec Mitchell

After 3 weeks, I've really gotten into my project. To put it in "layman's layman's terms" (as Dr. Peretz would say), I'm going to be working on optimizing the conditions of the nanocrystal syntheses. Today I ran a series of reactions to see what the best Cadmium to Selenium ratio would be. After 5 reactions and running UV-Vis and fluorescence spectrums on five samples from each of those reactions, the day was already over.

Over the past week, I've been experimenting with recovered dots (nanocrystals that were recollected from the spinner after we spun the films.) While the actual recovery of the dots isn't so difficult, it became a problem after the second recovery. This was because the dots became soluble in everything, so they couldn't be cleaned. Luckily the first recovery still works well, and allows us to change the concentration of the dots if we want.

Looking ahead, I still have to analyze the data from today. Tomorrow I'm going to be testing some of the films we previously spun. After that I'll be doing some more reactions to find how concentrated we can make the dots. The more concentrated, the better the yield will be (right now we get 1g of dots per 1L reaction, but we could bring that anywhere up to 50g of dots). I only have two weeks left, but I know the hard work is just beginning

-Alec