17 posts · 14,603 views
Full-time chemistry PhD student, part-time time-waster on Will and Beyond.
Will and Beyond
17 posts
Sort by Latest Post, Most Popular
View by Condensed, Full
- May 19, 2008
- 08:07 PM
- 1,848 views
Determining Nanoparticle Concentration
by Will in Will and Beyond
Back in March, I found a communication in JACS about determining the concentration of quantum dot nanoparticles by measuring their fluorescence burst counts by the Johnson group at York College. The QD solution (which could be in aqueous or organic solvent) was passed through a laser to induce the excitement and the different wavelengths emitted were separated by dichroic mirrors. The scheme is shown below.
They refer to this as a simple and accurate process. They do get good results, so I will give them accurate, but simple? I suppose if you work in lab that do... Read more »
C-y Zhang, & LW Johnson. (2008) Simple and Accurate Quantification of Quantum Dots via Single-Particle Counting. Journal of the American Chemical Society, 130(12), 3750-3751. DOI: 10.1021/ja711493q
Takashi Ito, Ronald Henriquez, & Richard Crooks. (2004) A Carbon Nanotube-Based Coulter Nanoparticle Counter. Accounts of Chemical Research, 37(12), 937-945. DOI: ar040108
- December 2, 2008
- 11:23 AM
- 1,167 views
Helium: Graphene Balloons and Nobility
by Will in Will and Beyond
I haven't done a journal post in almost three months. Although I keep up with journals via RSS, we stopped discussing literature in group meetings, so I haven't bothered to post anything. First off, I normally avoid linking to ScienceDaily, since they annoying make me look up journal references manually, but when I looked today, there was a nice references section at the bottom, which even listed the DOI and gave a link directly to the article. Kudos to them.
Considering how many RSS subscriptions I have, one of my primary ways of filtering through posts is by browsing for catchy titles, and "The Perfect Nanoballoon: How Ultrathin 'Graphene' Carbon Sheets Keep Everything Inside" is pretty catchy.
One of the disappointing things about balloons is that after about a day, they look very old and wrinkly. It's almost as if the balloon has experienced a lifetime of aging overnight. How does this happen? Balloons are typically made of latex, and latex has pores bigger than helium atoms. This allows the helium to leak out, and your birthday party souvenir to wilt.
Graphene is a pretty amazing material, with it's strength, conductivity, and simplicity. Thinking of using it as a balloon sounds like one of those eureka moments when you wake up in the middle of the night after having a weird dream about balloons.
This was first done experimentally in Nano Letters earlier this year. Experimentally in the sense that they used graphene and a helium flow, but disappointingly, didn't make an actual balloon. In continuing the trend of studying, but not making a graphene balloon, some experimentalists published an article in Applied Physics Letters where they do DFT studies.
I realize that this will most likely be used for more useful applications based on this idea, but I want a never-wilting balloon. If someone sells heavy ice just for the novelty, someone has to eventually make this balloon too.
All of this talk of helium reminded me of something else that I skimmed across in my RSS. ScienceDaily caught my eye with another catchy title: "Collapse Of Helium’s Chemical Nobility Predicted By Polish Chemist". The collapse of nobility makes this sound pretty epic, and mentioning anything Polish will also do it for me.
We were first taught that the noble gases are inert and unreactivity; they will always be monoatomic. Then eventually these ideas crash down around us when we were about things like XeF6. Even neon forms a few compounds. Helium was always holier though; the one atom that should never react with anything.
Wow, who knew that there was a helium monument.
Us poles always have to go and mess everything up. In the Polish Journal of Chemistry (see p. 11), the theoretical chemists have predicted two molecules: (HeO)(CsF) and (HeO)(NMe4F). I can't read the full article, since it's advanced publication, and they're not high-tech enough to post articles ASAP like the ACS (and pretty much every other modern journal). Speaking of high-tech, I really do like the new ACS website.
O. Leenaerts, B. Partoens, F. M. Peeters (2008). Graphene: A perfect nanoballoon Applied Physics Letters, 93 (19) DOI: 10.1063/1.3021413
Photo: Flickr
Mmm... graphene balloonsThink those would be expensive?Helium sculpture...?
Godspeed.... Read more »
O. Leenaerts, B. Partoens, & F. M. Peeters. (2008) Graphene: A perfect nanoballoon. Applied Physics Letters, 93(19), 193107. DOI: 10.1063/1.3021413
- September 11, 2008
- 04:30 PM
- 923 views
Quadruple-clicked Catenanes
by Will in Will and Beyond
Browsing through the ASAP articles on JACS, I came across 'General Method for Synthesis of Functionalized Macrocycles and Catenanes Utilizing "Click" Chemistry'. Far from my field, but sounded interesting. Then I noticed it was done by the Schuster group at NYU.
To refresh myself, I read a review by John E. Moses, The growing applications of click chemistry, and through my Supramolecular Chemistry textbook on catenanes.
So they start off by putting alkynes on the ends of a chain so they can be closed. Next, they throw in a copper complex, and allow the phenanthrolines to bind for 30 minutes.
Once the complex is formed, they throw in throw in a 3,5-diazide, 3, with a little bit of heat, and bam. The sulfonated bathophenanthroline, 4, is added to complex with the copper, so it can be removed from the system, leaving just the catenane system.
Normally, catenanes are produce in low yields, but the combination of the copper complex, with the 'spring-loaded' click reaction gives great yields as you can see in the figures. A control experiment without the copper only gave 7% yield and a bunch of other products.
This does not look like a very fun NMR.
Jackson D. Megiatto, David I. Schuster (2008). General Method for Synthesis of Functionalized Macrocycles and Catenanes Utilizing “Click” Chemistry Journal of the American Chemical Society DOI: 10.1021/ja8050519
Click go the azides
Around the copper complex
High-yield chemistry
Godspeed.... Read more »
Jackson D. Megiatto, & David I. Schuster. (2008) General Method for Synthesis of Functionalized Macrocycles and Catenanes Utilizing “Click” Chemistry. Journal of the American Chemical Society. DOI: 10.1021/ja8050519
- August 27, 2008
- 10:29 PM
- 899 views
Slushes, Nanowords and Footnotes
by Will in Will and Beyond
The science
An experimentalist, Z.H. Li from Fudan University, and a computationalist, (is that a word?) D.G. Truhlar from University of Minnesota published a paper in JACS, "Nanosolids, Slushes, and Nanoliquids: Characterization of Nanophases in Metal Clusters and Nanoparticles". The basic idea is transferring the concept of a melting point (well, range) from the bulk scale to the nanoscale.
They did so by studying aluminum clusters, Aln, where n is 10-300. Before I get into their findings, a quote: "For convenience we call the particles with a diameter less than ~1 nm clusters and those with diameters larger than ~1
nm nanoparticles." These are just arbitrary definitions, and it's good to define things like this, to be more specific for the rest of the paper. However, I can't decide if this seems backwards to me. While nanoparticles should be on the scale of nanometers, I always think of clusters as being larger. Do I have this backwards in my mind?
There's a lot of discussion in the paper about the computational aspect, but since I have zero background in computational chemistry, I'm going to skip over this completely, so look into it yourself if that's your thing. They start off by saying, "For the particle sizes studied here, most atoms need to be classified as surface atoms rather than as interior atoms with bulk properties characteristic of a macroscopic particle", which sounds necessary, but I question it's accuracy as n approaches 300 in their study.
Phase isn't as well defined as you approach the nanoscale; changes in heat capacity can be due to changes on the atomic level, such as changes in equilibrium of isomers, so that can't be used as a strict measure, as it often is on the bulk scale. This is a point that's repeated several times, that phase become more ambiguous at this scale, and it's difficult or impossible to determine some of these measurements experimentally. However, I'm sure that it's possible to determine phase at this level, just not with the methods that we traditionally use.
The nomenclature
The title has the words nanosolids, nanoliquids, nanophases, and nanoparticles in it. I've already discussed the overuse of the prefix nano-, but if they've taken it this far, why couldn't they just use the term nanoslush? That's a much more entertaining image to me.
Speaking of nanostuff, there was another ASAP paper that uses the word nanowheels.
The layout
Normally, I'm a big fan of the JACS layout, in that they use footnotes, rather than endnotes, but I think they need to be more flexible about this. When they see how a final paper looks, they should change it to endnotes if need be. Why would they need to do this? Look at the 3rd page of this paper:
More than 50% of this page (all of the stuff in red) is devoted to showing references, and that is just unnecessary. This is a 14 page article, and seemingly a good chunk of that is due to references.
Slurpee image: Jonas Rask Design
Zhen Hua Li, Donald G. Truhlar (2008). Nanosolids, Slushes, and Nanoliquids: Characterization of Nanophases in Metal Clusters and Nanoparticles Journal of the American Chemical Society DOI: 10.1021/ja802389d
Godspeed.... Read more »
Zhen Hua Li, & Donald G. Truhlar. (2008) Nanosolids, Slushes, and Nanoliquids: Characterization of Nanophases in Metal Clusters and Nanoparticles. Journal of the American Chemical Society. DOI: 10.1021/ja802389d
- February 19, 2009
- 07:08 PM
- 886 views
Coffee Grounds as Biofuel
by Will in Will and Beyond
Coffee chemistry[1] and green chemistry are both very fun, and here's a great combination of the two. The Misra group out of University of Nevada took used coffee grounds and used them to create biodiesel and fuel pellets. Below is a flow chart summarizing what they are proposing.
Biodiesel is simply made by transesterifying fats and oils. The chemistry is pretty basic, and I'm not going into it, but take a glance at Wikipedia if it's new to you. Coffee grounds contain oils; the Starbucks grounds that they used contained ~15% oil.[2]
To retrieve 15g of oil from 100g coffee grounds, it takes about 300mL of organic solvent, (works best with hexane extraction), and they were able to reuse that solvent in later steps. They monitored everything via HPLC, and did their analysis with GCMS.
MG, DG, and TG are referring to mono-, di- and triglycerides, and the FFA is free fat oils, which they propose making into soap. I would most definitely use coffee soap.
Once they extract the oil, the remaining waste can be used for composting, or made into fuel pellets. If they efficiently remove the oils and process the fuel pellets the group estimated that $8 million/year could be made[3] from Starbucks' US waste alone.
Ignoring the vague math, it seems like a great idea. Who knows, maybe in a few years big oil and Starbucks will go to war. After a little bit of searching it seems like I'm not the first person to cover this.
[1]: infiniflux! also loves coffee chemistry.
[2]: I wonder how much oil are in other types of coffee grounds: drip coffee maker vs. espresso maker vs. french press (which has leaves a lot of the oil in the coffee, and is delicious).
[3]: Their math for this (which can be found in the SI [PDF link]) doesn't really give any sources for how much it's going to cost to do all of this processing, so I'm skeptical.
Narasimharao Kondamudi, Susanta K. Mohapatra, Mano Misra (2008). Spent Coffee Grounds as a Versatile Source of Green Energy Journal of Agricultural and Food Chemistry, 56 (24), 11757-11760 DOI: 10.1021/jf802487s
Coffee = human fuelCoffee grounds = vehicle fuelIt's amazing stuff
Godspeed.... Read more »
Narasimharao Kondamudi, Susanta K. Mohapatra, & Mano Misra. (2008) Spent Coffee Grounds as a Versatile Source of Green Energy. Journal of Agricultural and Food Chemistry, 56(24), 11757-11760. DOI: 10.1021/jf802487s
- May 20, 2008
- 06:10 PM
- 802 views
Blue Quantum Dots by Microemulsion Oxidation
by Will in Will and Beyond
In an Inorganic Chemistry publication back in March 2008, Yadong Li's group at Tsingua Univ. synthesized CdSe nanoparticles that were small enough to fluoresce blue. Because of quantum confinement, nanoparticles (specifically quantum dots) fluoresce at shorter wavelengths with smaller radii. To synthesize quantum dots with radii this small is difficult; they must be smaller than 2 nm.
The method they employed was to first create nanoparticles by a microemulsion route, then mildly oxidize the nanoparticles to reduce them into smaller particles. The pretty pictur... Read more »
Liping Liu, Qing Peng, & Yadong Li. (2008) An Effective Oxidation Route to Blue Emission CdSe Quantum Dots. Inorganic Chemistry, 47(8), 3182-3187. DOI: 10.1021/ic702203c
- May 22, 2008
- 05:09 PM
- 790 views
Tricky Tricky Viruses
by Will in Will and Beyond
All I know about viruses I learned for the seminar that I gave a month ago or so. I've never taken biochem or virology, so there's my disclaimer.
Vaccinia (MVA) is a poxvirus, the class of viruses which includes smallpox. They're not fun organisms; the damage they do on cells is shown in the image above. MVA is a complex virus; it's not icosahedron or helical, and there's an intracellular and extracellular version. As far as viruses go, that's pretty complicated, they're generally more simple than this, structure-wise. Additionally, the Helenius group at ETH Zu... Read more »
J Mercer, & A Helenius. (2008) Vaccinia Virus Uses Macropinocytosis and Apoptotic Mimicry to Enter Host Cells. Science, 320(5875), 531-535. DOI: 10.1126/science.1155164
- May 21, 2008
- 08:08 PM
- 785 views
Iron Worms: Stealing Your Chromium
by Will in Will and Beyond
In April's Journal of Solid State Chemistry, Honggang Fu's group published a paper on iron oxide nanoworms being used for water treatment. They don't actually use the term nanoworms; they just say "iron oxide with wormlike morphology", but nanoworms sounds cooler, and I've heard the term used before. Morphology is a good word, but it just doesn't match up.
Anyway, the idea is that they were able to create iron oxide that looks like it does in the image above. Creepy looking. They took iron nitrate, mixed it in with a big block copolymer and refluxed it. They ha... Read more »
L WAN, K SHI, X TIAN, & H FU. (2008) Facile synthesis of iron oxide with wormlike morphology and their application in water treatment. Journal of Solid State Chemistry, 181(4), 735-740. DOI: 10.1016/j.jssc.2008.01.019
- May 15, 2008
- 02:15 PM
- 781 views
Chemistry classifies coffee
by Will in Will and Beyond
Lindinger's group at the Nestle Research Center in Switzerland published a study back in March 2008 in Analytical Chemistry about analyzing coffee with mass spec. I read about this on Engadget then promptly forgot about it. I even gave a presentation on it for my Analytical class, only later to see this in my RSS bookmarks.
Basically by using PTR-MS (proton transfer reaction mass spectrometry) they did an analysis of different coffees. They emphasized that this was a data-driven study, not a chemical analysis study, because they weren't necessarily analyzing the different comp... Read more »
C Lindinger, D Labbe, P Pollien, A Rytz, MA Juillerat, C Yeretzian, & I Blank. (2008) When Machine Tastes Coffee: Instrumental Approach To Predict the Sensory Profile of Espresso Coffee. Analytical Chemistry, 80(5), 1574-1581. DOI: 10.1021/ac702196z
- May 14, 2008
- 05:10 PM
- 771 views
Electrical Properties of Viruses Studied by AC-SPM
by Will in Will and Beyond
A paper was published in JACS (see below for reference) a couple months ago by the Matsui group at CUNY Hunter. The idea is that you can uniquely identify a virus by measuring its electrical properties.
We're not talking about a solution of viruses, this is measuring the electrochemistry of one individual virus particle, a virion. I'm not going to go into the details of the method, otherwise this post would be pages long, but the gist is that you put a virus onto a film of gold, locate the virus with AFM, then use the AFM tip and the gold film as electrodes and ru... Read more »
RI MacCuspie, N Nuraje, S-Y Lee, A Runge, & H Matsui. (2008) Comparison of Electrical Properties of Viruses Studied by AC Capacitance Scanning Probe Microscopy. Journal of the American Chemical Society, 130(3), 887-891. DOI: 10.1021/ja075244z
- March 19, 2008
- 09:08 PM
- 760 views
Global Warming... Maybe
by Will in Will and Beyond
I'm definitely not sold on global warming one way or the other. I don't think there's enough data to rule it out or prove it, but I do think research should continue. I'm not so sure I would sure Al Gore over it, though the idea is entertaining. I bring this up because I came across a 2006 paper from the Annual Review of Physical Chemistry, "Atmospheric Field Measurements of the Hydroxyl Radical Using Laser-Induced Fluorescence Spectroscopy". I found this in search of a paper to write about for my dynamics class, and I think I'll use it.
For the most part, I enj... Read more »
Dwayne Heard. (2006) ATMOSPHERIC FIELD MEASUREMENTS OF THE HYDROXYL RADICAL USING LASER-INDUCED FLUORESCENCE SPECTROSCOPY. Annual Review of Physical Chemistry, 57(1), 191-216. DOI: 10.1146/annurev.physchem.57.032905.104516
- March 19, 2008
- 09:08 PM
- 749 views
Detecting Mercury with DNA and Gold Nanoparticles
by Will in Will and Beyond
In my continued search for a paper to do my graduate student literature seminar, I came across this interesting paper.
Published about three weeks ago the web in JACS, researchers at the National University of Singapore have found a way to easily detect mercury in water. The method they are developing is very efficient because it can be performed in the field, without instrumentation, using just the naked in about 5 minutes.
Gold nanoparticles (NPs) are functionalized with two different strands of DNA - half of the NPs are functionalized with one stran... Read more »
X Xue, F Wang, & X Liu. (2008) One-Step, Room Temperature, Colorimetric Detection of Mercury (Hg2 ) Using DNA/Nanoparticle Conjugates. Journal of the American Chemical Society, 130(11), 3244-3245. DOI: 10.1021/ja076716c
- July 21, 2008
- 02:18 PM
- 740 views
Blatant Plagiarism
by Will in Will and Beyond
How do people get away with blatant plagiarism? Read the top introduction in the image below. Then read the second one. Seem familiar? It is the same, word for word. The first was published in Thin Solid Films in 2003 by C. D. Lokhande and his group in India at Shivaji University.
The second was plagiarized by J. J. Vittal and his group in Singapore at the National University of Singapore. The latter was published in the Journal of Materials Chemistry. The latter is definitely a better journal, but who cares? They cheated.
oh, maybe they didn't k... Read more »
Lu Tian, Ti Ouyang, Kian Loh, & Jagadese Vittal. (2006) La2S3 thin films from metal organic chemical vapor deposition of single-source precursor. Journal of Materials Chemistry, 16(3), 272. DOI: 10.1039/b511981b
G Bagde. (2003) Deposition and annealing effect on lanthanum sulfide thin films by spray pyrolysis. Thin Solid Films, 445(1), 1-6. DOI: 10.1016/S0040-6090(03)00467-X
- July 15, 2008
- 02:10 PM
- 714 views
Blatant Plagarism
by Will in Will and Beyond
How do people get away with blatant plagiarism? Read the top introduction in the image below. Then read the second one. Seem familiar? It is the same, word for word. The first was published in Thin Solid Films in 2003 by C. D. Lokhande and his group in India at Shivaji University.
The second was plagiarized by J. J. Vittal and his group in Singapore at the National University of Singapore. The latter was published in the Journal of Materials Chemistry. The latter is definitely a better journal, but who cares? They cheated.
oh, maybe they didn't k... Read more »
Lu Tian, Ti Ouyang, Kian Loh, & Jagadese Vittal. (2006) La2S3 thin films from metal organic chemical vapor deposition of single-source precursor. Journal of Materials Chemistry, 16(3), 272. DOI: 10.1039/b511981b
G Bagde. (2003) Deposition and annealing effect on lanthanum sulfide thin films by spray pyrolysis. Thin Solid Films, 445(1), 1-6. DOI: 10.1016/S0040-6090(03)00467-X
- August 6, 2008
- 01:11 PM
- 704 views
Cool abstract picture of the day and a Lack of binding
by Will in Will and Beyond
The Gardinier group at Marquette Univ. have developed a new pentadentate ligand alpha,alpha,alpha',alpha'-tetra(pyrazolyl)lutidine. They just published their first paper in Inorganic Chemistry about it, and it will be the first in a series. It's made by four pyridines bound to another pyridine and a couple of tertiary or quaternary carbons, resulting in the five nitrogens of the pyridines being available for binding. Their abstract image is below; I approve. It reminds me of the image which appears in my head when I think about the Scorpionates by Trofimenko.
Thi... Read more »
Tyler J. Morin, Brian Bennett, Sergey V. Lindeman, & James R. Gardinier. (2008) First-Row Transition-Metal Complexes of a New Pentadentate Ligand, α,α,α′,α′-Tetra(pyrazolyl)lutidine. Inorganic Chemistry. http://pubs.acs.org/cgi-bin/doilookup/?10.1021/ic801093q
- August 4, 2008
- 03:11 PM
- 676 views
Revisiting Aligned Carbon Nanotubes
by Will in Will and Beyond
A little less than two weeks ago, I wrote about well-aligned CNTs, which was published in JACS.
I don't read Science too much outside of monitoring the RSS feeds, but today I came across a very similar article, Self-Sorted, Aligned Nanotube Networks for Thin-Film Transistors. The ideas behind the work are very similar. In the Science paper, the work was being done on amine/phenyl functionalized silicon surfaces, which is a little more applicable industrially, as compared with the JACS paper which was done on gold surfaces. Yes, you can just put gold plating on silicon surfaces,... Read more »
M. C. LeMieux, M. Roberts, S. Barman, Y. W. Jin, J. M. Kim, & Z. Bao. (2008) Self-Sorted, Aligned Nanotube Networks for Thin-Film Transistors. Science, 321(5885), 101-104. http://www.sciencemag.org/cgi/doi/10.1126/science.1156588
- June 19, 2008
- 01:13 PM
- 608 views
Nanolithography: What's the Point
by Will in Will and Beyond
A paper entitled 'Floating Tip Nanolithography' appeared in my RSS reader this morning. I make it a point to scoff when I see the nano- prefix being overused, but this got me questioning the whole field (assuming nanolithography is considered a field?), not just the world itself. There's too much nanostuff, but that's the point I'm making here. (And in the paper they do say: "NANO" revolution, sigh.) Why do nanolithography at all? Is this just some proof of concept idea?
The wiki entry tells me that it's used for creating microcircuitboards. Okay, that's useful enough, but f... Read more »
Alexander Milner, Kaiyin Zhang, & Yehiam Prior. (2008) Floating Tip Nanolithography. Nano Letters. DOI: 10.1021/nl801203c
topics
join us!
Do you write about peer-reviewed research in your blog? Use ResearchBlogging.org to make it easy for your readers — and others from around the world — to find your serious posts about academic research.
If you don't have a blog, you can still use our site to learn about fascinating developments in cutting-edge research from around the world.
