Getting a Little Creaky There...

Oww. I feel elderly today.

There wasn't all that much to do in the lab today, so I cleaned the floor. Yes, the floor*. For safety reasons, only lab personnel can clean the floor - what with all the solvents and reagents and whatnot. And due to the nature of the lab itself, that floor gets really dirty, really fast.

Also by the nature of the lab, floor-cleaning is completely manual, as nothing less can get all the crap off. In other words, it's me with a squeegee**, a putty knife, alot of organic solvents, and several rolls of paper towels. And the lab is not a small place. The task makes me grateful for my very durable lab pants - among other things, it's still free of holes in unintended places, and since it's black, stains don't show.

Now I am sore all over, like some rheumatic oldster. Also going slightly crazy (well, crazier than usual) due to all that solvent fumes. Ow. The weekend is an opportune time to recuperate.

Note to coworkers who won't (or at least, shouldn't) be reading this anyway: the next person who makes a mess on the floor has to deal with me. And I do not plan to make it a pleasant experience. (*glowers*)

*The first time I had to do it, I became um, shall we say, rather bitter. Ok, extremely disgruntled. But I am more-or-less resigned to it now (if the student won't do it, who would?); besides, it's nearly the end of the term.
**For some reason (perhaps the solvent fumes have something to do with this), I like this word. Squeegee!

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Preliminary Report Statistics

Time taken to write report: 56 hours
Actual report length: 20 pages double-spaced, 3491 words
Appendix length: 17 pages
Total report length: 46 pages, 8032 words
Official word limit: 2500 words
Amout of crap in report: 80% (sorry, boss)
Imaginary dedication: to the next co-op student, who's stuck with doing all the work after I am gone. (And for that, I am truly sorry.)

And no, I am not done. It's editing and trimming time! (A confluence of circumstances permitted me to work on one single report for this long. Also, one of my supervisors is really nice, if a little condescending sometimes.)

It didn't help that two of my supervisors um, changed the report scope on me. At least they had the decency to tell me near the beginning of the week. It's hard to understand how they think, sometimes - they shot random, tangential comments and ideas all over the room. It's my job to put those pieces together.

In my opinion, the report's actually pretty useless. It has very little new information; almost everything I've written in it is already known by everyone at the lab. The report thus only serves three purposes:

1. It "collates" most of the existing information in one ungainly package
2. It's something for the next student to read - the report has practically everything the student will need to know about the project, including all my idiosyncracies
3. It's something for me to hand in to the University after this term

Well, ok, my coworkers also have to wade through the report, without the "insert comment" button in Microsoft Word. Finally, a chance to torment my coworkers after all these months. Heh.

Naturally, there are more reports to go; the difference is, I actually have some interest in those, because they are more "my" projects than "something that's all decided already, but boss wanted a report anyway". Sigh.

That's it for today. Editing will happen tomorrow, with a less exhausted pair of eyes. Thank the various computer scientists for writing LyX (automatic Table of Contents generation and label-tracking is awesome).

Reminder to self: I should obtain gifts for the lab, soon. End-of-term is coming.

An utterly tangentially random aside: ohhhhhhhh he meant Saint-Saëns! I had no idea, when he first said the name (I forgot who wrote the Carnival, shame on me...). Define he := boss, who was giving me a ride from lab to corporate HQ.

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Inverting Functions

Inverting functions is probably something we've all learnt in high school. Unfortunately, high-school techniques don't always work. (If only they do...)

From high school/first-year calculus: a (nice, simple, single-variable) function from (say) A to R, A a subset of R, y = f(x), is invertible iff it is one-to-one. Thus it's usually easy to tell whether a function is invertible or not - just find out whether it's one-to-one. Even visual inspection works, sometimes.

A blunt way to find inverses is to take the equation y = f(x), and solve for x. Another way to go is by using integrals and the inverse function theorem (roughly speaking*: dx/dy = 1/(dy/dx)), but integrating to give a closed form is, in general, not easy. Related to using integrals is to use differential equations, which is probably even harder than just using integrals directly.

Well, so now I have a function. It's a composite function, actually, so y = g(f(x)). Given y and a strictly-decreasing g(x), I want to find f(x). (I even have the values for x.)

Obviously, invert g.

But I can't invert g! It just won't invert! Argh!

Well. If I feel inclined to be all about approximations, I suppose I can use power series, assuming that g plays nice (I think it does, actually, but the number-crunching will be brutal).

All this is actually just a roundabout way for me to slack off so I can put off writing more reports - I need the function for one of the lower-priority projects, you see. Stupid reports. (I've missed my first deadline already. Sigh. Second deadline: everything by end of this week *fingers crossed*.)

(Incidentally: all those Wikipedia links are there because I've been doing chemistry for so long, I need reminders. It's a terrible thing, to be so math-deprived...)

*The multivariable versions of these things are bloody complicated and I've forgotten all about them (ahh, the joys of multivariable calculus**...). In truth, for many functions (multivariable or not) it's impossible to find a closed form for the inverse. I was hoping that this isn't the case for my function. Sigh.
**Actually, multivariable calculus was fun, partly because my class pretty much always proved and used theorems in full generality - no sordid number crunching!

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On the Company Christmas Party

I didn't drink anything alcoholic last night (despite the availability of lots of free booze), so why does my head hurt today? *mutters grumpily*

While I totally failed the schmoozing part of the program (I stood around and looked awkward instead), I did find the event fairly interesting. Too bad I didn't take pictures.

Nobody got dead drunk, though many got tipsy. It's hard not to get tipsy, I suppose - the first thing the waitress does upon seeing arrivals is to offer cocktails.

People are a little strange when they are tipsy. Well, more ridiculous than merely "strange", actually; no surprises there. Quite a few giggles and unusual ravings about silly things.

Being feminine in a formal setting is a challenge, as well. Youtube is actually quite useful as a crash course in makeup application. I still fail at using eyeliner, but the rest looked ok. I think. Nobody laughed outright, anyway. Also, high heels, despite the height advantage they confer, are deadly. Not only are they painful to wear, they lack sufficient friction on icy ground to make walking at my usual rate an option. How can people do this on a daily basis, I have no idea.

The jazz ensemble in attendance is pretty decent. Lots of random solos; why am I not surprised? However, the keyboardist's stage piano is absolutely lovely - a Roland RD-700GX! (That's Roland's top-of-the-line stage piano, by the way.) Most handsome being in the room that evening, I tell you, despite being a completely professional stage piano (i.e. far too many buttons, bells and whistles for an amateur player).

Something I've wanted to say to various guys throughout the party, but never did: No, I don't need you to get a drink for me. If I had wanted one, I would have gotten one myself. Now go away.

(In the end, I got myself a glass of water, just to shut people up. "Hey, look, I got a drink! It's water, though.")

Randomly, my boss wore a graph-paper dress shirt with his suit to the party. It was a wonderful shirt! (However, I felt no temptation to graph on it, since I don't like curve sketching anyway.)

More randomly, a senior member of the company cornered me to quiz me about my university, because his child is at the "where should I apply next year?" stage. I hope my sales pitch was sufficient.

Most randomly of all: the keyboardist hit on me. That was quite strange! Such a thing had never, ever happened to me before. You can tell how mentally mature my coworkers and their significant others are by comparing their reactions - most of my coworkers laughed (the bastards*), while their companions tend to be much nicer - even parental - about it.

Overall, it was a worthwhile party to go to, if only to find out from attending coworkers how a major project went. (The answer: the experiments worked, if imperfectly. Yay!) School and work are much easier than social interactions!

And now, one day later, I sit, slacking off. Must...write...reports...

*My coworkers all enjoy swearing; I fear that they have unduly influenced my own diction, as well.

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To-Do List, Writing Edition

I just realized that I really ought to have all my reports written by the beginning of December...which is in a week or so. Coupled with piecemeal data collection, this means that the inclination to run around amok panicking is um, quite strong. Hence a frantic to-do list!

The problem with being a student in a industrial research environment is that everyone piles their low-priority projects on the student. There are alot of such projects, believe me.

By priority:

Project R
This one is more like a proposal than anything else - the main work is intended to be done by the next poor sod student after me. (Why is it that my largest project is given to me last?)

• Write out the "chemical" section
• Write out the "mechanical" section
• Figure out which data I'll need to illustrate my points, and get them all off various lab computers
• Convert data into figures/tables and insert into document
• Write introduction, conclusion, recommendations, executive summary, acknowledgements
• Bibliography and citations
• Editing for formatting (the easy part)
• Editing for grammar and style (the hard part)
• Double-check
• Send it off for coworkers to read/critique
• Make revisions as necessary
• Bind final draft
• Submit to boss, along with an evaluation sheet for him to fill

I am planning for this to be submitted to the university as well; I'd like the draft for this sent off for critique by the beginning of next week. This weekend is going to be fun.

Project HS

• Finish data analysis (what there is of it)
• Figure out what the hell to write - so far, there is near-zero correlation between the variables I want to correlate *cough*
• Write content, introduction, conclusion, abstract, citations. This, unlike the other one, needs to be more-or-less in ACS article form.
• Do the two edits and coworker critique
• Revise, send off final draft to whoever may be vaguely interested.

This, let's try to finish this by the end of the first week of December.

Project pH
This goes pretty much the exact same way as Project HS (deadline and all), except it's more like a "communication" than an "article" - my data set is extraordinarily limited (as in, 5 data points or so), so there's no real conclusion I can get from it.

Project "my boss just thought it'd be fun to do this even though I think it's a waste of time"
This one will have an even more limited data set than Project pH. I might include it as part of Project R. Otherwise, it'll quite literally be a quick email to my boss - "hey, these are the results of what you wanted me to run last time; I don't trust the numbers (for various reasons), but here you go anyway." I'll also have to consult a coworker on the data, because the data contradicts conventional wisdom.

Project Titration
This is a side project, just for fun. It also provides some information to Project pH, but no one cares for this project but me.

• Think of ways to expedite the current procedure, which works but takes quite awhile.
• Write up, well, a lab report/SOP cross, with heavy emphasis on discussion.

I think I've got all the data I will have the chance to collect for this little project, so it'll just take a day for me to write it up if I know what I want to write (which I don't, yet).

Oh dammit, until I have the titlesec package installed and figured out, I have to write all these papers in Microsoft Word instead of my beloved LyX. Dammit! (In case it isn't obvious, I don't like Microsoft Word.)

Randomly: also, company Christmas party coming up. I need to um, make a few (more) purchases (already bought the major things, now onto the minor things). *Sigh*.

One more note to self: Pay Tuition! *Feels destitute*

[Edited]
The magical command in LyX for indenting entire blocks of text requires no titlesec:

{\addtolength{\leftskip}{amount} %in ERT
Section title
Text text text
} %in ERT

Beautiful! Now I can write my reports in LyX and annoy all my coworkers because their computers can't handle LyX (I'll give it to them in .pdf).

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Moral of the Day:*

Do not stand in front of a 1-inch** valve to a 1/3 full tank while trying to catch the latter's contents. Especially if the said valve is aimed right at you rather than downwards.

As a coworker had dryly remarked afterwards: It's a good way to learn. Particularly since the contents of the tank is at pH 2, and has amines in it. Ick. Fortunately, the use of the safety shower is not required. Just paper towels and plenty of complaining.

(And I just washed my lab clothes, too, dammit!)

*Alternate title: Add this to the "stupid undergrad stories" folder.
**Engineers and their quaint system of measurement...*mutters*

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Meet my Gran Plot

A Gran Plot is a rather nice way to find equivalence points in a titration given the titration curve itself. It'll even find analyte K_a (for an acid-base titration). There is some controversy as to exactly which points in the Gran plot to use, but overall I like Gran plots better than using derivatives, since calculating derivatives from data means that every single point on the derivative curve is approximate.

However, most people only show the lovely, linear part of the Gran plot (with a slight curvature near the equivalence point). So, meet my Gran plot.


*Resists urge to laugh*.

(Bonus: An observant reader will notice a second equivalence point on the plot.)

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Death of a Salesman

Let's just say that I committed manslaughter today on a good friend of mine. The evidence will be posted tomorrow because the corpse is still at my workplace.

Of course, that friend isn't human. It's the* pH probe. Yes, the new one, intended for clean samples. We've been through much, the pH probe and I, despite the short time in which we have been acquainted. Samples large and small, clear and opaque, mostly acidic and all aqueous, at a wide range of temperatures.

Unfortunately, little pH probes attached to portable pH meters are never intended for environments like a 200 L tank**, half-filled with a near-boiling solution, with a powerful mixer in the vicinity. The pH reading kept fluctuating, and I wasn't sure whether I actually dipped the probe into the liquid or not due to the steam (and a lid), so I dipped the probe in further. Unfortunately, the probe is surprisingly buoyant and doesn't sink well when there exists a strong "current". It strayed into places where it shouldn't have been - the mixer rotor. The rest, as they say, is history.

There was actually so much steam over the tank that I didn't notice the pH probe was brutally killed until I started getting even wackier readings than usual (i.e. error messages). Then I went through the stages of grief pretty quickly (I needed the pH in a hurry) and did whatever I could to compensate.

My coworkers took the news surprisingly well (we have an old probe stashed somewhere), but I am now very sad. *Sniff* What will I do without a reliable pH probe?

(I realize that the tank solution is now contaminated with bits of a pH probe, some saturated KCl, and something else - maybe AgCl or Hg₂Cl₂; considering the tank size, I am hoping that it won't be an issue.)

Incidentally, that new probe must've been the old probe's protégé or something, because the old probe hates me and does things like drifting and giving me wacky pH values which caused me to overshoot my intended pH value by two (i.e. 100 times, eep!) *Sad*. I'll have to coax it a bit tomorrow*** morning with an acid soak and a base dip.

(On a random tangent, I haven't gotten a chance to do my titration yet. I hope I'll have the time to do it soon...)

[Edited]
Sorry, picture will be forthcoming in a few days - overtime means that I crash pretty much immediately upon arriving back "home".

[Edited again]
Pictures:


*I almost wrote "my" pH probe, except, of course, it isn't.
**It's not actually a tank, and is somewhat ill-suited to the task (among other things, stuff leaches from it). But I'll call it a tank anyway.
***Yep, working on Remembrance day... *feels vaguely guilty*

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Cooking Carbonate Again

Previously, I've made some sodium carbonate for fun (even if the final experiments didn't work). This time, I need sodium carbonate for work.

The thing about my workplace is that they have minimal analytical reagents and equipment. An analytical balance that goes only to three decimal places. A pH meter with buffers. A few volumetric flasks. A burette*. There isn't even a single volumetric pipette in sight.

However, I want to carry out an acid-base titration**. The titrant and analyte are abundant in the lab, but I don't have any primary standards. Now what?

Possibly the most obvious solution would be to buy some standards. Things like KHP and sodium carbonate doesn't cost that much, even at analytical grade (I think). Unfortunately, it takes weeks for reagents to be delivered, and I don't have that much time.

In theory, of course, I can simply calculate the titrant concentration by measuring its pH. The accuracy and precision of the pH meter, however, leaves much to be desired, especially when the standard's pH will lie outside the usual calibration range of 4.01 to 10.00.

So here I am, cooking sodium carbonate so I can use it as a standard. Obviously, food grade reagents are not as pure as primary standards ought to be, but here's to hoping that they will be pure enough. I can't believe this, but I am actually nostalgic for a simple, KHP-NaOH-phenolphthalein titration. *Sigh*.

Which reminds me - the lab doesn't have any acid-base indicators except possibly phenolphthalein (which I'll have to borrow), either. At least there's the pH meter. *Another sigh*. I don't like monitoring titrations with pH because the amount of rinse water used during the titration will significantly influence results, whereas an indicator is somewhat immune to this dilution effect. The fact that a pH titration requires alot more readings doesn't help matters.

The lack of indicators in the titration makes me wonder, though. Usually, a carbonate-acid titration requires the reaction mixture to be boiled at indicator endpoint to expel CO₂ and to allow for a more accurate titration (otherwise the indicator changes colour prematurely due to dissolved carbonic acid). Given that I am monitoring the endpoint using pH, is there much point in me performing the boiling step? Will the inflection point be more obvious, or will there just be a little bump/spike on the pH versus volume curve right before the endpoint? (I am pretty sure the inflection point won't shift much - maybe by a drop of titrant or so.) This powerpoint suggests that yes, I ought to boil anyway, but laziness is a factor here, too...

Alternatively, what if I monitor the first endpoint with phenolphthalein instead? It's not a really good endpoint due to CO₂ absorption from the atmosphere, though. (Maybe if I perform the titration really fast...but that's optimism speaking here.)

The third alternative would be to do both - stick in both a pH probe and a few drops of phenolphthalein, and compare endpoints. The phenolphthalein will affect the pH a bit, but not much (ideally). The CO₂ absorption problem still applies, however.

And yes, I am well aware that my to-do list has things like "write essays" on it, not "toast baking soda" and "blog". I'll get back to work now...

*To it's credit, it's a *long* burette - 100 mL. Haven't seen that before. On the other hand, this means that I'll need a chair when taking readings. Dammit.
**It's a crappy way of determining pKa and molar mass (assuming monoproticity) of my analyte, but it's all I've got. Ideally, I want the temperature dependence of analyte pKa, but the van't Hoff equation needs information that I won't be able to get.

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And Now, A Moment of Silliness...

To (feebly) counteract the effects of my previous post, I offer a bit of levity.


(Yes, I am posting a picture of my lab notebooks instead of a picture of an enormous pot of solution, because the latter is much more difficult to get - I don't actually have access to the lab without my coworkers around.)

My official lab notebook at work is everything one can wish for - hardcover, permanently bound, pre-paginated and with space for project information and notarization...it even has instructions on how to maintain a lab notebook!

My *real* lab notebook is a dog-eared, much maligned spiral-bound booklet, filled with random instructions, calculations of all sorts (including stupid stuff like addition), and much of my raw data.

Technically, this is very poor practice, since there is actually a transfer of information between two lab notebooks. I certainly don't do this with notebooks for schoolwork. However, my little spiral-bound book actually fits in my lab coat pocket, and I can write anything in it - machine configurations, tricks not in the SOPs, random instrument parameters, sudden pieces of information flying my way, reminders to self, in addition to actual procedures, observations and data that I ought to be performing or collecting. I can even rip pages off to give to other people.

I learnt this trick in my first work term, actually. Most of the data there are titration volumes, so the little notebook is definitely much handier than an actual hardcover book (especially within the confines of a huge - but somewhat crowded - fume hood).

Both notebooks are kept in perhaps not the clearest, but certainly the simplest, style: chronologically. I also have tabulated data on my computer, of course. Maybe I should invest in colour-coded stickers so my coworkers can navigate through my notebook after my work term ends.

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Bucket Chemistry

It's almost a little disconcerting how fun it is to make solutions on a large scale. (Why yes, I will be using The Evil Additive.) "Large" as in about 50 kg. Given the limitations of the available lab equipment, the liberties taken with mass and volume measurements in making the solution are plenty to make a proper analytical chemist cringe. But the process itself is done in such a cavalier way, it's fun!

The first step is to simply add water to the solution container (maybe "holding tank" is a better phrase - it's large enough to merit a platform beside it for me to stand on). Alot of water. From the tap. With buckets. On the one hand, the buckets are graduated, so we "sort of" know how much water we are adding. On the other hand...it's a freaking bucket; how accurate can it be? Of course, I can weigh the water one bucket at a time, but that'll make me sad.

The second step is to put in the mixer. Yay for automated devices! It's a relatively heavy mixer, powered by compressed air (whee!); I dragoon a coworker into the exciting task of holding it for me.

The third step is to adjust the pH of the water with HCl or NaOH, as necessary. The poor little portable pH meter that I use doesn't really fare too well in this environment, but it's the only pH meter I have. Trying to avoid getting the pH probe cable tangled with the mixer looks vaguely like fishing in a whirlpool.

The fourth step consists of me adding a molten solute into the water. With a ladle. Rather like a manic chef making an insanely huge pot of soup.

The fifth step consists of re-adjusting the pH, again, so the solute actually dissolves properly.

The sixth step is to add The Evil Additive. This time, I bought a sifter - much handier than a sieve! There are still chunkies* in the solution if I use the sifter, but at least they are smaller. Having a mechanical mixer to agitate the solution for me is also nice. The only problem with the sifter is that it's nearly impossible to clean afterwards and now the one I have is dead from me disassembling it. Oh well, I'll see if I can fix it when I get back to work on Monday.

The seventh step is to add just a little more water to bring the solution up to the appropriate mass. Another bucket, coming up.

The last step is for my purposes only - I take a sample and check its pH. Because one of the additives has weak acid-base properties, the pH tends to stay where I want it. Unfortunately, pH happens to be temperature dependent, and I make my solution hot, so as the sample cools, the pH changes. Water evaporation is a also a problem as the solution sits, heated, over time.

For what it's worth, I do weigh out the amount of the various additives I used. Of course there are ways to make the process more accurate; such improvements are deemed to be too labour-intensive for now, however.

What really strikes me about the solution-making process is the incongruity of it all. If I have the chance I'd love to take a picture of the process. Oh well, at least it works.

*Yes, at the lab, this is a technical term.

(If you found this post silly, well, yes it is. I am undergoing something of an "existential crisis" right now and posts like these help keep me relatively sane.)

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Pancakes in the Lab

It's so easy to take making aqueous solutions for granted. Dump solute in water, mix. In some cases, things may be complicated by temperature, solubility issues and pH (e.g. arsenic trioxide dissolves much better in basic solutions than in neutral, silver cations and halide anions don't usually stay in solution together). In other cases, though, the problem is mechanical.

In the past few days, I was required to experiment with various additives to a particular solution. One additive is liquid, completely miscible with water, and is therefore quite easy to mix. A second additive doesn't dissolve very well and prefers to remain suspended in the solution, but it is a free flowing powder, fairly easy to disperse in a controlled way.

The third additive, however, is evil. It's like flour - an extremely fine powder that just won't disperse easily. Adding this stuff to my solution is like adding flour to milk in a pancake batter* - lumps are inevitable. However, lumps are ok in pancakes. Not ok in this particular solution. Argh. Also like flour, I can't make a slurry out of the additive first - it becomes all doughy and unmanagable. (Actually, it's worse than flour - like gelatin, the stuff swells upon the addition of water. Ick.)

In the end, my coworker had the brilliant idea of sifting the additive into the solution, with vigorous mixing. Like many theoretically brilliant ideas, it doesn't work nearly so well in practice. My arm is sore from stirring so much (stirbars don't agitate the solution well enough), and it's impossible to sift and stir simultaneously. Even worse, in the end the additive *still* clumps, although the clumps are relatively small. Next time (if there is a next time), I am making my coworker try his brilliant idea himself.

With any luck, the Powers that Be will decide to not use this third additive. With my luck, though, it will probably be the additive of choice. We shall see.

*Actually, when making pancakes the usual procedure calls for adding the liquid to the dry ingredients, but the result is still a lumpy, viscous mess.

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Engineers and Balances

At my workplace, half of my coworkers are mechanical engineers of one stripe or another. From paper towel racks made of coat hangers to pilot plant extensions, these engineers build them all.

I admire these coworkers for their mechanical ingenuity - I hardly know which wrench is which*, much less the ways of using a wrench to fix a recalcitrant pump (no, don't whack it). Their knowledge of such seemingly mundane things as valves and fittings, and how they work together in a large system, is amazing. It's a humbling experience to watch these engineers go about their work, and honestly I'd love to help out more often except I will get in their way.**

Sometimes I wonder how such competence turn out - trust me, the majority of engineering students at my university aren't good for anything but consuming beer***. How do they survive in a machine shop drunk/hungover is beyond me.

Anyway, able as my engineering coworkers may be, they don't notice the little things that aren't quite in their field of view. Things that a student can notice.

This leads to me obsessively-compulsively doing things like levelling the top-loading balance after every single time the engineers move it. Yes, it's just a top-loading balance, but levelling just takes a minute or two****, and even a top-loading balance deserves to be treated properly. If they treat the analytical balance like this I think I'll go kick the perpetrator. And no, I am not letting them engineers touch the precious new pH probes.

*Interestingly, depending on type, *both* ends of the wrench can be usable.
**Yes, I am jealous of all those toys they get to play with. More gadgets! More!
***Based on first-year observations. Of course, that's a biased sample.
****The knack for levelling balances is partially innate; it's amusing to watch people who don't have the skill swear for fifteen minutes straight as they try to level the balance. (Of course I offer to help...afterwards *grin*).

Bitter rant-y postscript:
Sadly my job still consists mostly of cleaning - no samples are forthcoming, so there's no data collection/analysis and nothing else to do. Coworkers compliment me on how well I clean stuff - isn't that sad when I am capable of so much more?

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Happy Happy Joy Joy!

Sorry, I was a little incoherent in the blog post title there. It's just that I am quite delighted with new pH electrodes that have finally arrived at work. Now there are separate probes for "clean" and "dirty" samples, which is wonderful. *Clutches the new probes to my chest* I'll take good care of you all...

Why yes, now that you mention it, I can indeed be easily satisfied by the simplest little things. Work is still more-or-less trivial*, but now I have new probes to play with. Yay! Now if I have access to deionized water, that'll be even better. At least the lab has kimwipes.

Reminder to self: the conductivity probe** needs recalibrating also. This one is needy in its own little way, too, but at least the probe can be stored dry.

Strangely enough, my coworkers don't like to calibrate pH meters. I have no idea why.

Incidentally, my supervisor claims that that I'll have something more interesting to do when certain machinery parts arrive. Hmm. Should I be optimistic?

On the down side, my coworkers kind of like my curve-fitting attempts, but the operative phrase is "kind of". There's this interval of particular interest that my functions don't always model well, and when my curves fail, they fail spectacularly. This seems to be hinting towards using splines for curve-fitting. Sigh. (Actually, splines are awesome. The problem is that now there are lots more parameters to worry about, not all of which will have nice relationships with other variables.)

*I spent five hours scrubbing containers of one variety or another***. Sad. As a small consolation, almost everyone else in the lab is cleaning today, too.
**The SI unit for conductance is the siemens. The old name, however, makes me smile.
***It is really rather odd to see a lab with loaf pans and cookie sheets among the list of equipment. They do have their uses, however.

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Vaguely Hopeful, Curve-Fitting Edition

One of the projects at work might actually be yielding something potentially interesting. So all is not lost (yet).

When there's nothing to clean at work, nobody ever thinks of any work for me to do, so I spend the time curve-fitting the painstakingly gathered data (it's either that or twiddle my thumbs - no surfing the Internet on company time!). Since the samples are wildly variable in their properties, the curves aren't expected to fit very well*. In fact, my coworkers probably think that what I do is a waste of time. (Now if they actually *have* something for me to do, I won't be "wasting" my time...).

Anyway, I think I've actually got something that's surprisingly nice. R² > 0.9, for the most part, and visually the curves seem to fit, also. I realize that R² values can be horribly misleading, and I might've calculated it wrong, but I don't know a better way of assessing fit because of my aversion to statistics. (Too bad I am not dealing with probability distributions.) Don't know *why* the data follows such a curve, though. Something to show my coworkers on Monday, perhaps.

Reminder to self: try to automate the data analysis process. (Ick, programming...but there's no denying that things will go faster if the code works.)

Random background:

The project** basically consists of subjecting the samples of interest to strong external forces, and see what happens. It belonged to a previous student and I am supposed to continue the work. The question is, what work, precisely? My coworkers are all pretty "experimental" people (*mutters about chemists who work near mechanical engineers for too long*); previous work on the topic consists of slowly gathering data and plotting them randomly in hopes for some correlation between different factors, then bullsh- making up elucidating the reasons behind the correlations. It's such a haphazard approach, and I don't like it. (Also, some of the observed phenomena are actually fairly well known, and well, why re-invent the wheel?)

Anyway, if one has discovered the correlations between the various parameters and explained them, what more is there to do? "Collect more data", they say, but to what end? What should be done with the data? (Yes, curve-fitting is my answer to this question, but it's a pretty limited answer.)

Some new paths include applying the force in slightly different ways (e.g. constant, piecewise, or oscillatory instead of logarithmic or linear) and see what happens. (The answer to this question, so far, is "nothing much", by the way. But we'll see.)

*At this point, some people will probably say: "welcome to real life". To this I say: real life sometimes matches with theory gorgeously well, too! (E.g. many calibration curves are beautifully linear. *Sigh*, I miss analytical chemistry.)
**I really should think up some handles*** for the projects since there's more than one and now everything is referred to as "the project". Hm.
***Too much Matlab. Bah.

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Janitorial Assistant

Because that's the unofficial title of my job. Warning: another rant/whine, coming up.

Tasks in the past few weeks include cleaning tools, making soap (or, more accurately, diluting soap), handing out paper towels and solvent, mopping the floor when there are spills, and running several relatively docile gadgets (one of which is the much-abused pH meter). Charming, I am sure.

While the coworkers are decent people, nobody around here explains much, and I end up being so confused that I don't really have questions anyway. The company would probably have been better off hiring a mechanic or an electrician, because that's what much of the work is about. At any rate, there's no way they'll let an ikkle student help with this sort of task, lest the said student breaks something (which I admittedly have an unfortunate propensity to do).

Shoutout to certain senior coworkers: I will appreciate it if you treat me like the adult I am, not ten years younger, even if the work I do can be competently completed by such a child.

The "projects" aren't going too well because previously collected data are literally all over the place, poorly stored, and I obtain new data at the rate of one point every other day, at best. My "control" samples precipitate at the temperature where I want to make my measurements. My emulsions don't break nicely. Sigh.

Today I have a day off while the rest of the company pursues "teambuilding activities" from which, thankfully, I am exempt.

The only positive side is that I think I have a very rough model which fits the data. One can only hope that the coefficients of the model actually correlates with existing data to give something useful.

Filling out the timesheet is going to be fun. Three and a half more months remain in this term; with luck perhaps I may get to do something interesting.

Postscript: school research project is going extraordinarily slowly. I am stuck again.

[Edited]
Of course, I spoke too soon. The form of the model doesn't work for a particular type of data. Wonderful.

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Breaking Emulsions

In the lab, there's this (oil in water) emulsion that I want to break in order to study the continuous (aqueous) phase. I am just trying to put my random ideas here.

By design, the emulsion is pretty stable, so doing simple things like washing with a solvent won't work. Because I want to study the continuous phase, I don't want to change the chemical composition of the emulsion too much either. Letting the emulsion sit will work, eventually, with the operative word being "eventually".

My first thought was distillation. In retrospect, it's pretty obviously a bad idea.

My second thought was centrifugation. Lacking a centrifuge, and lacking the resources to rig one up, this is a no go. (Too cheap to buy a drill/something that spins really fast, or I'll try it...)

From The Internet I heard that the following works:

• Freezing
• Adding a saturated NaCl solution
• Adding an alcohol (e.g. isopropanol or glycerol)

For the first one, I'll have to see if I can take some samples home and stick them in the freezer. For the other two, I am not sure how much reagent is required to break the emulsion. The reagents are cheap (always a good thing), and pretty harmless in terms of changing composition, but they will change ionic strength and/or dilute the continuous phase down for sure.

For some reason, pharmacies don't sell the 99% isopropanol much anymore. It's getting increasingly difficult to find the good stuff these days.

Reminder to self: keep the "scrap" emulsion that nobody wants and play with them.


[Edited]
Experimental results, for those who wanted to know:

• I didn't try freezing because I kept forgetting to take the sample to the freezer. Oops.
• Salting causes creaming, but it's still hard to get at the continuous phase
• Alcohol works a little *too* well - the stuff seizes up to this semi-solid mass with all the continuous phase trapped inside (and no way to get it out)

Sadly enough, letting the emulsion sit for a few days seems to work the best. Sigh.

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One-Liner

This is awesome. That's all.
(It's a laser particle sizer. There are two lasers, in fact. So cool!)

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Stunning Practices

I know, I know. Different fields have different standards as to what constitutes "acceptable practice". That much is obvious enough when comparing organic lab with analytical lab - in the former, one rinses most glassware with acetone; in the latter, washing glassware with acetone is an anathema because the solvent is so dirty. In addition, even different workplaces with similar intentions will have different practices. Monitoring the pH inside a pipe is much different from measuring the pH of a 100 mL water sample, even if the meter itself works much the same way.

Some methods, however, are a little beyond the pale. Let's just say that what I saw at work today almost makes me want to shriek: DON'T DO THAT! Of course, I can't do that, either.

In no particular order:

Let's first deal with the pH meter. The usual kind we see in analytical labs. Most labs have one (or many, as the case may be), and most people knows how to calibrate and use one. It's important to calibrate the meter fairly often (e.g. at least once a day or once every time the meter gets turned on, whichever comes first; more often, within reason, is better). When measuring the pH of a solution, equilibriation is important (especially with the more senile meters), and stirring the sample is much preferable to not stirring it. Stirring the solution using the pH meter is not ok. It's also important to keep the pH meter in a suitable medium (e.g. a suitable buffer, or saturated KCl) when the meter is not in use. Plain water is possibly the worst medium to use. The fact that I mentioned all these things is indicative of what the people at the lab did (or didn't do, as the case may be).

Solutions were made using tap water. Warm tap water. Eek. (Warm water is used for a reason, but tap?)

Analysis of samples were also done with tap water (e.g. as blanks). Double eek.

Drying of glassware involve wiping the inside of the glassware (e.g. beaker) with paper towel. Not kimwipes, paper towel. At least it's not the cheap kind.

Fume hood sash *should* be kept as low as possible, but because some people were too tall, they kept the sash far above what it should be. On the positive side, the fume hoods actually work.

The entire lab smells like nonaqeuous solvents because there was alot of cleaning done outside the fume hood. At least it's not ether.

One saving grace good practice: solutions are made up by mass, not by volume. Most concentrations are in mass percents.

One interesting thing to watch: for one of the solutions, the substance to be dissolved is melted before it is added to water. I have a feeling that this is done to make weighing easier. (Beats chipping chunks out of a bottle, that's for sure.)

(Yes, yes, this is all ranting, but I spent most of the day being useless at work, and there wasn't anything else to do other than making critical observations.)

Postscript 1: I have received a project from work, too. Alas, I have no idea where am I supposed to go with this. The topic is either really specific and trivial, e.g. "dependence of acid concentration on pH", or really complicated and somewhat general, e.g. "what are the factors influencing acid concentration in a complex mixture". Also, some work has been done on the subject already.

Postscript 2: I forgot all my linear algebra. All the cool stuff, anyway (what does "positive definite" have to do with sketching conics again?). *Sad.*

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H2S Detection Tubes!

The H₂S safety training I went through today consists mostly of "practical" information, as it is intended for um, the "mechanical"/"industrial technician" type of audience, machine operators and such. Topics include things such as the properties of hydrogen sulfide, safety response in case of an accident, instructions on wearing a self-containing breathing apparatus, and using gas monitors. All quite straightforward, but I did find one thing really cool: H₂S detector tubes!

Obligatory picture:

These things are for determining the concentration of H₂S in air. Other tubes exist for detecting other gases, though they all generally work the same way.

Basically, the ampouled, calibrated glass tube contains a compound that changes colour in the presence of the analyte gas. To use it, break off both ends of the tube and insert it into a specialized pump (arrow points towards the pump). The pump can be a piston or a bellows, and is used to draw a specified amount of gaseous sample (e.g. 100 mL) through the tube; it also has a marker that tells us how long to wait for the reaction to be complete. Multiple draws of sample may be required depending on the tube. Finally, we simply read the concentration of the gas by looking at where the discolouration ends.

These things are cheaper than electronic monitors, and wrecking a tube is much cheaper than wrecking a sensor. (Wrecking the pump will cost alot more, though.) The error is pretty large, though, say ~25%, so it's more used for industrial safety checks than for analytical purposes.

What I like the most about the H₂S detection tubes is that they are filled with lead acetate! I want! (Sadly, I don't get to keep one. Boo.)

I also learnt a little bit of first aid (e.g. different types of rescue carries). A couple of fellow students were volunteered into being "victims"*; sadly, they are too heavy for me to lift. Erk. Things like the portable compressed air tanks with harness and regulator were heavy, too, but at least I can lift that. No glasses with face mask though - doesn't fit.

Oh, and apparently FeS is pyrophoric (with no form specified! Is it a fine powder? A chunk of pyrite? Storage conditions?). Without more details, I don't quite believe that.

*The "volunteers" were both male, and the instructor made them repeat the following:
Lord our father, let us protect our family jewels.
It took awhile for the "volunteers" to realize why. (I couldn't stop laughing for awhile when I heard that...lowbrow humour, I know.)

[Edited]
I spelled "tubes" wrong in the title. Erk.

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