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Category: lab day

Tuesday, 9 October 2012

08:54 – More lab work today, but I should finish making up most of the solutions we need for the new batch of biology kits. Then I’ll start filling bottles.

12:58 – Angela Merkel has apparently survived her trip to Greece, although many were concerned about her safety visiting a country that has compared her with Adolph Hitler. Love Merkel or hate her, one has to admit that she is a brave woman. The Greeks laid on a personal security detail for her that included 7,000 cops, water cannon, and at least one helicopter. Of course, they’ll probably expect Germany to pay for that, just as they expect Germany to pay for everything else.

I now have all but a few of the solutions made up for the new batch of biology kits. The main ones still missing are the ones I’m lacking a chemical to make up. Everything I need is currently on order, and I still have enough spares to put together several biology kits if we need them before the chemicals show up.

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Monday, 8 October 2012

08:47 – I switched over this morning from air conditioning to heating. It was under 68F (20C) in the house, and the high today is to be only 50F (10C), with lows tonight in the low 40’s (~ 5C). This cool snap is to last only a few days. We’ll soon be back to needing neither heating nor air conditioning.

Barbara was stunned when she read in the newspaper this morning that one of her co-workers died in a house fire over the weekend. She said today would be tough at work. The woman who died was well-known and well-liked throughout the firm.

Today is a federal holiday, so USPS won’t be delivering. I’ll batch up the kits ordered yesterday, today, and tomorrow morning, and ship them all tomorrow. Today, I’ll spend some time in the lab making up solutions for the biology kits. As I’ve mentioned before, my natural tendency is to use the oh-my-god-we’re-out inventory method. So yesterday I checked inventory against the chemical makeup instructions and found I was out of Eosin Y and Crystal Violet. I just ordered enough of both to make up two liters of each stain.

Fortunately, our filling method means we always have a few left over. For example, the kits include 15 mL each of the Hucker’s Crystal Violet stain and the Eosin Y stain. I make up one liter of each of those at a time, and label 60 bottles for each. We actually get about 66 bottles from a liter, so we typically have six bottles left unlabeled. After we’ve filled bottles, I print the extra labels we need and label the extra bottles. So as of now I have half a dozen bottles of each of those stains still in stock. That means I can make up half a dozen biology kits pretty quickly if we run out before the next batch of 30 is ready.

10:57 – That worked out well. As Barbara and her sister clear out their parents’ old home, Barbara is bringing home stuff her parents don’t want but that she wants or thinks I might want. Saturday, she brought me something I didn’t know existed: a 2-liter polypropylene measuring cup. I’m using that today to make up stuff I need two liters of, including Benedict’s reagent, Barfoed’s reagent, biuret reagent, and so on.

Ordinarily, I just make up stuff that I need in 2-liter quantities in 2-liter soda bottles. (I’ve established where the 2-liter index line falls on soda bottles, so they function as pretty accurate 2-liter “volumetric flasks”–easily within 1% accuracy.) But the problem with soda bottles is that they are made of PET, which some of the solutions I make up will damage. Some, like 6 M sodium hydroxide, damage PET instantly, literally. If I pour 6 M NaOH into a PET bottle, the bottle instantly turns from clear to cloudy white, as the strong base solution starts de-polymerizing the plastic. Having a reasonably accurate 2-liter PP measuring container makes things a lot easier. I’d have bought one (or several) long ago if I’d known they existed.

11:46 – Hmmm. Coyotes may soon be hanging out in your backyard

I’m not worried about Colin. At 70 or 75 pounds (32 to 34 kilos), he’d tear even a large male coyote to pieces. And coyotes are afraid of him because his ears make him look wolf-like. And between the two of us, even a pack of coyotes is going to shy away.

Nor do I worry about black bears. They’re smart, essentially super-dogs. Any bear we see around here is much more likely to run for it than attack or stand and fight.

But if I see a mountain lion roaming around this neighborhood, I’ll shoot it. I don’t care what the law says. Mountain lions, like all cats, are stupid. They don’t have enough sense to fear people and their fire-sticks. Coyotes, being Canidae, and bears, being honorary Canidae, do.

13:07 – How smart are Border Collies? Pretty damned smart. I’ve been running up and down the stairs all day today, working in my lab making up solutions for the new batch of biology kits. Colin completely ignores my trips up and down the stairs, lying on the sofa and watching me the whole time.

Until an hour or so ago, when I headed downstairs to drive over and pick up the newspaper for some friends who are out of town. There was absolutely no difference between that and the other trips I’d made downstairs, but somehow Colin knew I was going to leave the house, so he started barking like crazy. I did nothing to indicate that I was leaving the house. I didn’t check the front door to make sure it was locked (it always is during the day), rattle my car keys, or anything else. So how did he know this trip downstairs was different? I wouldn’t have known.

Crap. I just realized how he knew. I wear my glasses when I’m working on the computer and when I drive, but not when I’m working in the lab. When I headed downstairs to leave the house, I was wearing my glasses. Geez. That’s pretty subtle for a human, let alone a dog.

PS. It’s even more subtle than I thought. I just realized that I wear my glasses when I’m going to leave the house. When I’m running up and down stairs to and from the lab, I’m wearing splash goggles. Geez.

16:06 – If my first love is organic chemistry, coordination chemistry isn’t far behind. I was just down in the lab making up two liters of biuret reagent. I started by dissolving 23.6 grams of copper(II) sulfate pentahydrate in a liter of DI water. (Well, actually, I made up 94.5 mL of 1 M copper(II) sulfate to one liter, which amounts to the same thing.) I then added 33.0 grams of potassium sodium tartrate to the copper sulfate solution with stirring. The solution immediately turned from bright blue to greenish blue and became cloudy. Oops. That was insoluble copper(II) tartrate precipitating out. No worries. I then added 7.0 grams of potassium iodide, which turned the slurry distinctly greenish, but still cloudy. That was insoluble copper(II) iodide making its appearance. What a mess. Then I dissolved 128.4 grams of sodium hydroxide in water, made it up to 600 mL, and added that solution with stirring to the pale greenish slurry. As soon as the hydroxide solution hit the copper solution, the mixture turned an intense deep blue color. When I finished stirring, the precipitate was gone and I had a clear deep blue solution. I love coordination compounds.

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Thursday, 2 August 2012

08:09 – Mario Draghi made what may in retrospect be recognized as a strategic blunder last week when he announced that the ECB would do whatever was necessary to save the euro. It was certainly a tactical blunder by anyone’s standard. Draghi’s comment led to a big upswing in the markets, which took his word for it. The trouble is, it is not within the power of Draghi or the ECB to save the euro, and whatever measures he announces today will either fall well short of what is required or will exceed the authority of the ECB.

The Germans do not control the ECB, and it’s quite possible that Draghi will today announce that the ECB will grant the ESM a banking license. Doing so is not in their power, and is specifically prohibited by treaty, but that may not stop them. And if the ECB announces that it will grant the ESM a banking license, the Germans will go berserk. In effect, granting the ESM a banking license will allow it to make unlimited purchases of sovereign bonds without “sterilizing” those purchases by selling other bonds that it already holds, which means those purchases will be funded by printing money. That is the line in the sand that Germany refuses to cross. If the ECB takes this step, it paints Germany into a corner with only one way out: departing the euro and returning to its own sovereign currency. And you can bet that Germany, which absolutely refuses to give the southern tier what amounts to an unlimited right to spend Germany’s money, will depart the euro before it allows that to happen.

So, Draghi has two choices. He can announce steps that are grossly insufficient to save the euro, and the markets will respond accordingly. Or he can announce that the ECB will grant the ESM a banking license, and Germany will respond accordingly. It sucks to be Draghi.

10:00 – What a shocker. Mario Draghi announced precisely nothing, and the markets are responding accordingly. Draghi didn’t give them the ESM banking license. He didn’t even cut the interest rate. All he did was promise to do something unspecified at some unspecified future date. So much for yet another “last chance to save the euro”. News flash: there is no chance, last or otherwise, for the euro. Speaking of which, I just moved series two of The Walking Dead to the top of our Netflix disc queue.

I just spent a couple hours cleaning up my lab, unpacking and inventorying chemicals, and so on. I really need to get some horizontal space freed up.

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Tuesday, 31 July 2012

07:48 – I spent most of yesterday doing purchase orders for chemicals and other components for the forensic science kits. I’ll do more of that today, along with getting started on making up solutions for the kits. I also have a few solutions that I need to make up for the batch of 60 chemistry kits that’s currently in progress.

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Monday, 16 July 2012

08:02 – We’re in pretty good shape right now on chemistry kits and biology kits. Orders have slacked off a bit for now, so I’m going to spend some time in the lab making up solutions for the forensics kits. Before I do that, though, I need to wash up a bunch of stuff.

One of the advantages of having a lot of glassware and plasticware is that I don’t have to stop in the middle of doing something to wash stuff up. One of the disadvantages is that I don’t have to stop in the middle of doing something to wash stuff up. As it is, when I finish using a vessel, I just rinse it thoroughly and set it aside to drain. So, as of now, I’d guess that I have maybe 50 rinsed-but-not-washed beakers, mostly 500 mL and 1 L, about the same number of graduated cylinders (ranging from 100 mL to 2 L), maybe a dozen volumetric flasks, a couple of filtering flasks, a dozen or so Erlenmeyers, probably 50 each stirring rods and spatulas, and a partridge in a pear tree.

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Friday, 13 July 2012

10:03 – Another lab day today. As usual, I’ve saved the most obnoxious solutions for last. Stuff like concentrated acetic acid, ammonia, hydrochloric acid, and so on. Very concentrated solutions of some chemicals are called “fuming”, as in “fuming nitric acid” or “fuming sulfuric acid”. No one talks about “fuming acetic acid” or “fuming ammonia” or “fuming hydrochloric acid” because the usual concentrations already emit noxious fumes, and those fumes are sufficient to knock your socks off. That’s one major reason I decided to include 6 M solutions of those chemicals in the kits. It would actually have been easier to provide standard concentrated versions–17 M acetic acid, 15 M ammonia, and 12 M hydrochloric acid–but the 6 M solutions are usable for our purposes and the fumes are a lot less obnoxious.

I also need to start getting solutions prepared for the forensics kits. Several of those are hazardous–three or four are basically concentrated sulfuric acid with minor additions–but at least none of them are particularly obnoxious in terms of fumes.

14:05 – I just made something I didn’t know existed: iodine syrup. I was making up three liters of IKI (iodine/potassium iodide) solution that’s 0.1 molar with respect to both iodine and iodide. That meant I needed 38.07 g of iodine and 49.80 g of potassium iodide.

Now, the thing is, iodine is almost insoluble in water. But in the presence of equimolar or more iodide ions, each iodine molecule bonds with an iodide ion to form a triiodide ion, which is extremely soluble in water. But the speed of dissolution depends on the concentration of the iodide ion. If I’d simply dissolved that 49.80 g of potassium iodide in about three liters of water, added the 38.07 g of iodine, and made up the solution to three liters, the iodine would have dissolved. Eventually. It might have taken literally a month to dissolve, but it would have dissolved.

But iodine dissolves very quickly in a concentrated iodide solution, the more concentrated, the better. Potassium iodide is extremely soluble. At room temperature, that 49.80 g of potassium iodide will dissolve in about 36 mL of water. So I weighed out 49.80 g of potassium iodide in a glass 250 mL beaker, added just enough DI water to dissolve the salt, and then added 38.07 g of iodine. As far as I could tell, the iodine crystals dissolved instantly. I say as far as I could tell, because the liquid in the beaker instantly turned an opaque black, so opaque that I couldn’t see any light through the liquid even holding the beaker up against an overhead fluorescent tube and looking through the bottom of the beaker and a couple centimeters of liquid.

If there’d still been iodine crystals in the bottom of the beaker, I wouldn’t have been able to tell. I tried tilting the beaker back and forth to see if any crystals were visible on the bottom of the beaker, but there weren’t. Still, on general principles, I kept swirling the beaker for a few seconds every minute for ten minutes or so. That’s how I discovered that there is such a thing as iodine syrup. The stuff was viscous, kind of like vegetable oil. Not surprising, I guess, with almost 90 g of solids dissolved in maybe 50 mL of water.

Finally, I decided to give it go, so I carefully poured the liquid into a 1 L volumetric flask, which was the largest I have. I was kind of expecting iodine crystals to reveal themselves in the bottom of the beaker, but there weren’t any. So I made up the solution to 1.0 L and transferred it to the storage container, adding two more 1 L flasks’ worth of water. My volumetric flasks are calibrated to-contain rather than to-deliver, but I know from previous tests that the flasks actually deliver about 999+ mL. So I added just enough water to the storage container to make it up to exactly 3.0 L, give or take a mL.

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Saturday, 18 February 2012

10:17 – Along with doing laundry, it’s another lab day for me today, while Barbara labels and fills containers and makes up subassemblies for the biology kits. She’s working upstairs today, filling containers with non-hazardous materials. Tomorrow, we’ll work downstairs, filling containers with hazardous materials. Well, actually, they’re not hazardous, except to our work surfaces and floors. I’m making up several stains today, most of which would indelibly stain counters, tables, and hardwood floors. We’ll fill those containers in the basement.

12:55 – I was doing fine until I made up the last of the stains for the biology kit, Hucker’s crystal violet. When I inverted the container to mix the solution, the cap leaked. So my hands now have pretty (and indelible) purple stains. I wasn’t wearing gloves because this stain is hazardous only in the sense that it, well, stains things. Oh, well. All working chemists get used to having stains on their hands.

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Friday, 17 February 2012

10:13 – Today is a miscellaneous day. I’m going to take a break from writing and get some work done in the lab. I also have a few more purchase orders to get out for the biology kits.

Interestingly, I had to fight off a guy today who wanted to order a biology kit right now. As I pointed out, he had no idea what was in the kit or how much it would cost. He wanted to send me extra money and have me refund the difference when we’d finally set the price. I finally convinced him that we would allocate the very first kit to him and ship it as soon as it became available.

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Friday, 22 July 2011

08:55 – Following the crisis summit, there’s lots of joy in the EU. The feeling among people who don’t understand much about economics is that Greece is saved, the Euro is saved, they’re all saved. Economists and market analysts know better. What the crisis summit accomplished was necessary, but by no means sufficient. All that it really accomplished was to put off the reckoning for a short time, perhaps 90 days or less.

In one very ominous sign, Bulgaria announced that it was putting its plans to join the Eurozone on hold indefinitely. In effect, Bulgaria said that it believes its own currency is stronger than the Euro. And it may well be right. This vote of no-confidence in the Euro will not go unnoticed by investors.

And, of course, Fitch has already declared Greek debt to be in default, with Moody’s and S&P no doubt soon to follow. We’re assured by the Euro authorities that this default is “partial” and “temporary” and “selective”, but as far as investors are concerned, default is default. Nor are investors stupid. They did notice that the crisis meeting left the EU bailout fund at its current level, when it actually needed to be at least tripled in size to have any hope of propping up Spain and Italy as their debt comes due. Investors also noticed that the crisis meeting did nothing to address the critical liquidity problem among European banks. In fact, it worsened it by demanding that the banks “voluntarily” take a hit to their balance sheets on Greek debt, albeit concealing the damage by allowing the banks to continue carrying essentially worthless Greek debt instruments at face value rather than market value.

As hundreds of billions of Spanish and Italian debt matures over the next few months, it’s going to become abundantly clear that the crisis summit accomplished nothing but delaying the problem for a few weeks. Even Keynesian economist Paul Krugman gets it.

Nor is it certain that Merkel and the other leaders of the wealthier northern European countries can deliver what they promised at the summit conference. They have their own legislatures and voters to worry about. German voters almost universally perceive past and future bailouts as simple transfers of money from their own pockets to profligate southern countries, and they’ve had about enough. In Holland, this whole fiasco has accomplished something previously thought impossible: Dutch political parties, from far left to far right and everything in between, are united in their opposition to these huge transfers of their money to southern countries.

So Merkel, Sarkozy, and other leaders are walking a very fine line. Supporting what was needed to actually solve the problem would end up with them and their parties being routed at the polls. That solution, beginning with Eurobonds and ending with full fiscal and political union, is simply unacceptable to voters in Germany, Austria, Holland, and Finland. And rightly so, because the inevitable result would be a united Europe as the world’s newest third-world country.

Anyone who works with plasticware in a lab should keep the chemical resistance of various types of plastics in mind. If it weren’t for the high cost, the various Teflon plastics would be ideal. They’re resistant to almost anything, and anything they’re not resistant to is something I probably don’t want to be using anyway. Polypropylene (PP) and the polyethylenes (LDPE and HDPE) are, with some exceptions, pretty resistant to most chemicals. Polyethylene terephthalate, PET, is most familiar as softdrink bottles. It’s transparent, while PP, LDPE, and HDPE are translucent or opaque, depending on thickness and type. PET is also resistant to most dilute chemicals as well as alcohol and some other organic solvents. What it’s not resistant to, among other things, is concentrated strong acids.

So, yesterday I was down in the lab, making up 2 liters each of various chemical solutions. I was using 2-liter PET Coke bottles as mixing vessels. Among the solutions I was making up was 0.1 M iron(II) sulfate. Like most iron(II) salts, iron(II) sulfate has a nasty habit of spontaneously oxidizing to the iron(III) salt, with the spare iron ions reacting to form insoluble iron hydroxide and iron oxides. The result is a cloudy mess. The way to avoid that is to have sulfate ions present in excess, which is most easily done by adding a small amount of concentrated sulfuric acid to the iron(II) sulfate solution. So there I was, with about 1.5 L of distilled water in a clean 2-liter Coke bottle. I started to add 8 mL of 98% sulfuric acid, and realized as I started to pour what was going to happen.

Yep, as I trickled the concentrated sulfuric acid into the bottle, it ran down the inside of the bottle and instantly started depolymerizing the PET. My pretty transparent bottle turned cloudy white as the PET went from the transparent amorphous form to the opaque semi-crystalline form. I quickly dumped the contents of the bottle down the drain before the PET depolymerized completely. I don’t often have do-overs when I’m making up solutions, but this was one of them.

09:27 – Here’s a pretty amazing video of a group of people in a small boat, at considerable risk to themselves, saving a young humpback whale that had become entangled in a gill net. Even a juvenile humpback could have capsized their boat or turned it into kindling. But the humpback seemed to realize that these humans were trying to help it, and it docilely allowed them to do so. At about 6:30 in, the whale is free. She puts on an incredible display of joy, or perhaps thanks to her saviors. (H/T to Jerry Coyne)

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Tuesday, 19 July 2011

08:28 – Spain auctioned a couple billion worth of short-term bonds today. They kept the face value low and the maturities short, hoping to cherry-pick low interest rates and thereby demonstrate that the market still has confidence in Spanish debt, which it doesn’t. Even with the low face value and short maturities, they ended up paying nearly a full percentage point more than they did on their last auction of similar bonds a month or so ago. That bodes very ill for future bond auctions for Spain, and particularly for Italy, which has a huge amount of debt that needs to be refinanced in the coming months. The next Spanish bond auction is set for Thursday, the same day the EU holds its crisis meeting. That auction is for long-term bonds, which are likely to sell at disastrously high interest rates, if at all.

Lab day today.

12:12 – Merkel says that nothing that happens at the summit meeting Thursday will solve the Greece crisis, and she’s right. But I think what she’s really doing is signaling that, as far as Germany is concerned, enough is enough. All of the “solutions” proposed thus far involve Germany paying the lion’s share of the costs, and Germans are tired of being sucked dry to prop up a poor southern fringe EU country that’s going to fail no matter what happens. Germans rightly consider any additional funding provided to Greece to be good money after bad.

At this point, I really don’t see any alternative to the Eurozone collapsing into fragments. Even if the Greece problem were solvable, which it isn’t, Greece is the least of the Eurozone’s problems. The gorilla in the room is Spanish and particularly Italian debt, hundreds of billions of which will need to be refinanced in the coming year. There is simply no way that Germany can fund that effort, and any money it throws down the Greek rat hole now is simply damaging its future prospects. The real question is whether Germany will opt in the relatively near future to abandon the Euro and return to the Deutschmark, or whether Germany will join with France, the Netherlands, and other relatively stronger northern economies in a new Eurozone. My guess is the former. Germany was never really happy about having a common currency, and events have proved them right.

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