Day: April 28, 2014

Monday, 28 April 2014

08:01 – Barbara is headed back to work this morning, after being off for a week. That means Colin is likely to be a bit demonic today, expecting more attention than I’ll be able to give him. I’ll be working on filling the backlog of labeled bottles, starting with ones for biology kits. Costco shipped the second identical Core i3 laptop to me this morning. I’ll be a lot happier when it’s here and set up to produce shipping labels.

I guess I’m just not as interesting as I used to be. Over the weekend, I happened across some archived web site stats, so I compared them to my current ones. Nowadays, 1,000 page reads per day is a pretty good day, and I seldom have more than 1,200 per day. Ten years ago, a good day was 10,000 to 15,000 page reads, and my heaviest days were routinely over 20,000 page reads. Making matters worse, now each day is its own page, while back then I had an entire week’s entries on one page. I conclude that my audience now is maybe 5% of what it was back then. Oh, well. As I’ve said before, I write my journal for me. If anyone else chooses to read it, fine. But I really don’t care how many people read it.

10:45 – Yuck. I just realized that among the biology kit chemical bottles I need to fill are 90 each of glyercol and 1.5% methylcellulose, two of my least-favorite chemicals to fill. The problem is that they’re both extremely viscous. That means they’re difficult to fill bottles with. Using my automated dispensers is difficult because it’s a struggle both to fill the dispensing chamber on the upstroke and to dispense into the bottles on the downstroke. At times, I’ve tried filling manually, but the problem with that is that I’m using narrow-mouth 15 mL bottles and the glycerol or methylcellulose tends to blurp over the mouth and run down the sides.

With glycerol, I can at least heat it before filling the bottles. The viscosity of glycerol at 50C is about one tenth what it is at 20C, albeit still about 200 times the viscosity of water. Methylcellulose, conversely, actually becomes more viscous as the temperature increases. There’s no point to cooling it, because the viscosity is essentially level from room temperature down to the freezing point.

Every time I have to fill glycerol and methylcellulose bottles, I swear that next time I’ll use 30 mL bottles instead of 15 mL bottles. The mouth of a 30 mL bottle is enough wider than that of a 15 mL that it’s much easier to fill manually. But I always forget, so this time I’ve gone out and noted that in the procedures list while I’m thinking about it.

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