Bio Sugar Solvents

Well, I was looking for a Eutectic mix to use for the upper bound of a “Smith Scale” thermometer (as I mentioned in the Degrees of Degrees posting) and got side tracked by a very interesting thing…

Deep Eutectic Solvents

First, a digression on Eutectic Metal mixtures:

A Eutectic is a mixture of things that melts / solidifies at one particular point. It is typically significantly lower temperature than either part alone. So mix some lead and some tin and start cooling it, one or the other will form crystals first and leave the solution. Gradually what is left approaches the Eutectic Point, when the temperature stops dropping until the whole mass solidifies.

BTW, I sort of like Eutectic Solder, at Tin 63% / Lead 37% mix with 183 C / 361.4 F melt, or Rose’s Metal, a eutectic mix of Bismuth 50%, Lead 25% and Tin 25%, but have not yet settled… Rose’s metal is listed as having a melt point of 98 C / 208 F in one page and 100C / 212 F melt point in another, so needs more research. I kind of like the Eutectic Solder as it is now readily available, but could even have been made in ancient Egyptian times. It also gives about 360 degrees above 0 F, so using the ammonium salt mix for one end and Eutectic Solder for the other gives 360 degrees of almost the same size as an F degree ;-) But being that close it’s kind of hard to claim it as ‘new’ and not just ‘close but slightly off’…

So this same eutectic idea has a lot of uses. A nice solder that does not have a pasty stage, so far fewer cold soldered joints. Eutectic salts that hold a constant temperature as heat is added or removed (commonly used for storing solar energy overnight while keeping temperatures in a range you like. 68-72 F for passive room temperature stabilizing. In the very high hundreds to thousands of degrees for storing solar thermal at concentrating solar thermal electric facilities.

Sodium Chloride and Ice form a Eutectic Mixture at temperatures below the freezing point of water. That is why putting salt on ice causes it to melt. The water is pulled out of the ice into the eutectic solution until it reaches that stable, lower, temperature. Then with excess ice you can make ice cream. With excess salt you can clear frozen roads.

So there are many eutectic metal alloys, but only a few commonly used and well documented. Field’s Metal and Wood’s Metal are (or were) used in things like fire sprinklers. At a specific temperature, they melt, and let the water run… Wood’s Metal is 158 F / 70 C (but has lead and cadmium in it – so is now considered evil). Lead 26.7% Tin 13.3% Cadmium 10%. Cadmium is a fairly horrid toxin. Lead is toxic, but not to the degree that would warrant the present paranoia about it.

Field’s Metal is a safer replacement. It melts at 144 F / 62 C and has Bismuth 32.5% Tin 16.5% Indum 51%. Other than Indium being a bit rare and Bismuth not being in the local hardware store it’s a great idea for anywhere that people might occupy. OTOH, anywhere that the fire is burning up is likely to have a fair amount of lead in the electronics anyway so I’m not seeing all that much advantage…

Part of the reason we had a Bronze Age was that mixing copper and tin or copper and zinc gives an alloy that melts at a lower temperature, so is easier to create and work.

But more to the point: One can find all sorts of eutectic mixes, be they metals, salts, organics.

On To Organics

So, while wandering around looking for an interesting Eutectic Mix that would make for a nice upper calibration point of a thermometer, I ran into a bit of Unsettling Science. (That’s my neologism for what happens to “Settled Science” when it runs into something closer to the truth / newer and more complete ;-)

For many years I’d sporadically wondered why certain compounds kept showing up in biochemistry. It was not a very important nagging… just a slightly unsettled feeling. A ‘something is not complete there’ feeling. Citric Acid. Malic Acid. Lactic Acid is just about everywhere and I have some making Sourdough as I type. (and some other organic acids) Along with all those sugars. Glucose, sucrose, fructose, etc. It just seemed like there were a few more loose ends than ought to be. In particular, the way Maple Sap is such a sugar rich solution. It just seemed like the tree was being ‘wasteful’ of it’s energy stores leaving them in solution when they could be stuck away as starches.

I’d basically decided to just classify them as “sloppy nature” and not worry about it (but still it was a bit of a bother…) I mean, really. WHY have so many plants got sugars all over. They can just leak out when in solution. WHY have so many plants got various organic acids laying all over. Again they can just be lost from solutions. The amount of Citric Acid needed for the Krebs / Citric Acid cycle is way smaller than what you find in your Citrus Fruits…

But life is not long enough to follow EVERY loose end to a conclusion. You need to pick the ones that are interesting and let the others go. For the others, you can either accept a “forever nagging spot” or paper over it with a “plausible even if I don’t like it”. Rather than go insane from too many unsatisfied itches, I chose to paper over with “well, there must be a good reason and the plant knows.” And moved on.

Now it looks like some clever folks have found out what the ‘good reason’ is, and it has the potential to open whole new areas of chemical synthesis and whole new understandings of how life works. Heck who knows, there might even be some applicability to things like eutectic mixes in ice cores… As various biological dusts get added to ice, what happens to solubilities again?…

The first paper I ran into had a Greenwash flavor to it. Wandering past that I found the original PDF version:

http://www.plantphysiol.org/content/156/4/1701.full

http://media.leidenuniv.nl/legacy/2011-pp-nades.pdf

Are Natural Deep Eutectic Solvents the Missing Link in Understanding Cellular Metabolism and Physiology?[W]
Young Hae Choi1, Jaap van Spronsen1, Yuntao Dai, Marianne Verberne, Frank Hollmann, Isabel W.C.E. Arends, Geert-Jan Witkamp and Robert Verpoorte*
[…]
we asked ourselves why a few very simple molecules are always present in considerable amounts in all microbial, mammalian, and plant cells. It seems that these compounds must serve some basic function in living cells and organisms. These compounds include sugars, some amino acids, choline, and some organic acids such as malic acid, citric acid, lactic acid, and succinic acid. With the exception of sugars, which may serve as storage products and a source of energy, the other compounds are present in such large amounts that it does not make sense to consider them as only intermediates in metabolic pathways.

Here, we develop a novel theory about the role of these compounds, which may explain many questions in the biochemistry of cells and organisms. The theory is based on analogy with green chemistry, where in past years various synthetic ionic liquids (ILs) have been developed for chemical and enzymatic reactions as well as for the extraction of natural products.

So these folks looked in more depth, saw that there wasn’t a simple answer and discovered some really interesting things. It’s at times like this that I regret not scratching some itches… Then I remember that trying to keep all the itches leads to insanity and figure I’m better off reading about it now from someone else ;-)

But it is only in recent years that ILs and deep eutectic solvents (DES) have been revisited by chemical engineering, because such solvents can replace conventional organic solvents. Mixing salts and/or organic compounds may cause a considerable reduction of the melting point, turning them into liquids even at very low temperatures. Using the liquids made from synthetic chemicals, ILs and DES now have many different applications such as dissolving polymers and metals and as media for biotransformation (Welton, 1999; Wasserscheid and Keim, 2000; Abbott et al., 2004; Gorke et al., 2008). In fact, many of the synthetic ILs contain choline and in some cases also natural organic acids.

In analogy with the synthetic ILs, we hypothesized that the metabolites that occur in large amounts in cells may form a third type of liquid, one separate from water and lipids. Taking the plant metabolomics data we have collected over recent years into consideration, we saw a clear parallel with the synthetic ILs. The above-mentioned major cellular constituents seemed perfect candidates for making ILs and DES. As the first step, we made various combinations of these candidates, thereby discovering more than 30 combinations that form viscous liquids (Table I). Here, we will use “natural deep eutectic solvents” (NADES) as a common term for these mixtures. The preparation of NADES and NMR measurements are described in Supplemental Materials and Methods S1.

The article goes on to show various mixes of organic acids and sugars and choline and some other bits can make rather nice ionic liquids that enable various interesting biochemical reactions. Often giving a different mix of products or giving some interesting selectivity options over the products.

The bottom line is that they found a variety of things in living cells dissolve into those DES better than into water or lipids and that even things like starches and cellulose have some greater activity. So if you want to create starches or cellulose, or move it around, it looks like these Deep Eutectic Solvents have a great deal to offer.

Suddenly it makes a lot more sense why Citrus Fruit are full of Citric Acid, why Yogurt makes a lot of Lactic Acid (why our muscles do too, when we exert too fast… it isn’t an inefficiency, it’s a step…) and even why so many fruits are filled with both sugars and organic acids. Heck, even corn in the milk stage has them. Where there is a lot of biochemistry happening, there are a lot of the Eutectic Solvent ingredients around.

That sugars in sap also help prevent freeze damage may be secondary to assisting in materials transport and to assisting in metabolic processes.

Plants in particular have a bunch of things in them that don’t dissolve all that well in water (vis trees not washing away in the rain) nor in lipids. Yet a mushroom can liquefy and absorb it easily. Somehow all sorts of living things can pick up and move all sorts of molecules that are not all THAT easily dissolved in water or lipids. (And besides, lipids are not all that well mixed with the water based parts, so you have a solvent barrier between the two that has to be bridged…)

This raises the question of how these compounds are biosynthesized and stored. For example, the flowers of Sophora species contain between 10% and 30% dry mass of the sparsely water-soluble flavonoid rutin (Paniwnyk et al., 2001). In biosynthesis, it is generally thought that the enzyme-mediated reactions in cells occur in water. However, this raises questions of how these reactions function with substrates and products that are poorly soluble in water. In addition, the biosynthesis of water-insoluble polymers such as cellulose, amylose, and lignins probably needs a stage of the macromolecule being dissolved to enable the further addition of building blocks.

To assess the possibility of NADES being the third liquid phase in organisms in which certain biosynthetic steps or storage of products may occur, the solubility of some common natural products in NADES was measured. For example, we found that the solubility of the flavonoid rutin in various NADES was 50 to 100 times higher than in water (Fig. 2). Moreover, the completely water-insoluble paclitaxel and ginkgolide B showed high solubility: 0.81 and 5.85 mg mL−1, respectively, in Glc-choline chloride. Considering macromolecules, DNA (from male salmon), albumin, and amylase did show good solubility in some of the NADES tested. The solubility of the salmon DNA was shown to be 39.4 mg mL−1 in malic acid:Pro (1:1) compared with 26.9 mg mL−1 in water. The albumin solubility was 30.6 mg mL−1 in Fru:Glc:Suc (1:1:1) and 235.0 mg mL−1 in water. Even the non-water-soluble polysaccharide, starch, showed a solubility of 17.2 mg mL−1 in Glc:choline chloride (1:1).

There is a whole lot more in the paper, so hit the link. It covers things like freeze protection and dessication protection and a variety of ways this can enhance survival in difficult conditions.

For me, one of the more interesting potentials (though NOT said in the article) is that it seems to serve as an alternative Ionic Solvent to water. This implies it might be possible to form life without water at all. Purely based on DES / Lipid chemistry. That, at least for now, has to stay in the realm of Science Fiction… But it does present the potential to have a life form evolve on a hydrocarbon / CO2 rich world without a lot of water present.

So to handle those hard to handle biochemicals, it looks like Nature’s Trick is to use a Eutectic Mix of sugars and organic acids. The “Deep”part refers to how deep the melt temperature is depressed.

http://en.wikipedia.org/wiki/Deep_eutectic_solvent

A deep eutectic solvent or DES is a type of ionic solvent with special properties composed of a mixture which forms a eutectic with a melting point much lower than either of the individual components. The first generation eutectic solvents were based on mixtures of quaternary ammonium salts with hydrogen donors such as amines and carboxylic acids. The deep eutectic phenomenon was first described in 2003 for a mixture of choline chloride (2-hydroxyethyl-trimethylammonium chloride) and urea in a 1:2 mole ratio, respectively. Choline chloride has a melting point of 302 °C and that of urea is 133 °C. The eutectic mixture melts as low as 12 °C. There are four types of eutectic solvents:

That is one heck of a lot of melt point depression. It also explains why so many sugary things end up sticky ;-)

It looks to me like water is needed mostly to make things liquid at ‘closer to zero’ and that a non-water life form at, say, 100 C could be a theoretical possible… Though they might find water caustic and dissolve in it !

There isn’t a whole lot more in the wiki, so I’m just going to quote the whole thing here. Not surprising for a field that looks like it has all of about 8 years of significant interest under it’s belt. (Probably a good field for new students to head into. Lots of room for discovery / Thesis Topics…)

The DESs have been studied for their applicability in industry at lab level, and the DES described above was found to be able to dissolve many metal salts like lithium chloride (solubility 2.5 mol/L) and copper(II) oxide (solubility 0.12 mol/L). In this capacity these solvents are used for metal cleaning prior to electroplating. Because the solvent is conductive it also has a potential application in electropolishing. Organic compounds such as benzoic acid (solubility 0.82 mol/L) also have great solubility and this even includes cellulose. Compared to ordinary solvents, eutectic solvents also have a very low VOC and are non-flammable. Other deep eutectic solvents of choline chloride are formed with malonic acid at 0 °C, phenol at -40 °C and glycerol at -35 °C. Compared to ionic liquids which share many charactistics but are ionic compounds and not ionic mixtures, deep eutectic solvents are cheaper to make, much less toxic and sometimes biodegradable.

Some have suggested the possibility that carboxylic acids in conjunction with compounds such as sugar alcohols show promise and potential as a DES. A small group of undergraduate researchers at a small college in middle Tennessee have reportedly formulated a solvent that shows potential for having practical applications in green chemistry and could possibly have commercial applications in varying fields. They have not released their formulations or ratios, however it has been rumored the solvent was derived from some combination of carboxylic acid and an unknown sugar alcohol.

Due to the increase in research activities on DESs and their applications, it was necessary to characterize them (measure their physical properties and establish a database). So far, one research only published by American Chemical Society/Journal of Chemical and Engineering Data, had dealt with the task of the characterization of these solvents. That research took DESs based on Phosphonium salts as a subject to its study, because this type of salts was yet to be studied.

The applicability of DESs in industry is still subject to a wide study. A search on the internet for “Deep Eutectic Solvents” can return lot of results,
but a specific search with proper keywords can lead to the exact research groups that are researching on DESs. Few papers are already published on DESs’ applications, and it is expected that this will change dramatically in the near future.

So a “watch this space” seems in order.

New industrial chemistry.
New understandings of biochemistry.
New applications in organic chemistry.

And maybe, just maybe, some new planets to look at as potential places to find life. Those a bit shy on water, but rich in organics. Both higher temperature (water vaporized) or potentially lower temperature where liquid hydrocarbons could provide the freeze depression while the organic acids provide the ionic solvent character.

I wonder if anyone has studied Liquid Methane / Ethane / Propane DES mixes?…

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About E.M.Smith

A technical managerial sort interested in things from Stonehenge to computer science. My present "hot buttons' are the mythology of Climate Change and ancient metrology; but things change...
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15 Responses to Bio Sugar Solvents

  1. Jason Calley says:

    @ E.M. “Bismuth not being in the local hardware store ”

    Ah! Thank the environmentalists — you CAN get bismuth at the hardware stores!

    There are special shotgun shells made for hunting waterfowl that use bismuth shot instead of the much feared lead. I think that the bismuth is normally a bit over 98% pure with the rest being tin.

    Buy some shells. Melt the shot down on your stove.

  2. adolfogiurfa says:

    @E.M.: You really surprise us for your polymath abilities.
    One word about eviron-mentalists: Back in the 1960´s or 70´s someone had the perverse idea of concocting a brutal generalization of the word “chemical”, forming indeed an “eutectic” with dissolves common people´s brains. Thus anything became a “chemical”, as something not pertaining to this world. Cadmium was considered among those “chemicals” and, by a gracious extension, all cadmium pigments “chemicals” became forbidden, and a special law was issued (in “Grünes Partei”´s Europe, of course), while reality shows that only salts of this metal have a L.D.(lethal doses) of about 10 mg/kg (of body weight) while cadmium pigments 10 GRAMS per kilo, so in order for a person to poison with a soluble salt had to EAT, say 10mg x 80 kgs=800 milligrams of such a salt (of course no one has such an “appetite”) and in the case of Cadmium pigments, that person would have to have really a big “appetite”: 10 grams x 80 = 800 grams (almost one Kg.) to be (supposedly) fatally poisoned. (BTW: I built a plant for cadmium pigments where a distracted workman with his mouth wide opened over a pump, swallowed in much more than such an amount…and he still lives 20 years after such event). Well, Europe even established a final date for the manufacture prohibition…but all what it happened was that all those factories moved to Asia, as it was never found a good substitute for those pigments, and Europe leaders were not going to easily accept that their Mercedes or Volvos paint fading away under UV sun rays´(Cadmium pigments have the highest “solidity” under UV light).
    * Now, about “eutectics”: You risk being confounded if not drowned in a soup of letters; and this is what happens with our “Über-settled-science”: The more complicated, the more “cool” and “intelligent”, being the obvious “symptom” of self conceited individuals, who were indulged by Daddy and Mommy, or individuals who imitate the former as a way to ascend in the “social ladder”: Both, when grown up, use “mutual caressing”, as shown by Desmond Morris in his book “The Naked Ape”, as a means, not to remove their fleas away, but to remove such unpleasant “parasites” who, not having being indulged by Daddy and Mommy in their early years, have developed a sane reasoning, and, because of that, menace their comforted and dreaming awake existence.
    Such healthy working individuals, whose life, not having being facilitated by anyone and who daily endeavor in struggle for life, perfectly know much more simple laws, which explain reality in by far easier terminology: That of “objective science”.
    Well, in order not to be confounded in an inextricable tangle of words and “cool” concepts: Eutectics, pH, musical notes, polymerization, energy…whatever names you could choose, it has been explained from old.
    We could, of course, just present in its original terminology the ancient knowledge, but our minds´deformation, thanks, again, to the blessings of our modern “education” impede us such simple approach, so I have taken the recourse of presenting it in a “cooler” way (some of you, will recognize in it the “feng-shui”´s compass, the I-Ching´s “Bah-Gooah”, etc.):

    http://www.giurfa.com/unified_field.xlsx
    http://www.giurfa.com/unified_field_explained.pptx

  3. TIM CLARK says:

    Well, I’m not real sure where Adolfo was going, but if he was saying that these materials have been worked with for years, but just renamed, then I concur. I guess these folks are trying to get some type of specific nomenclature standardized. Which is great, I’m not one to poo-poo good research. There’s a whole branch of science on carbohydrate chemistry and about 5 journals because starch, as an additive, does interesting things.
    I used a vast array of these materials on an experimental level without knowing exactly what they did. We were using them as solvents to increase plant uptake, selective penetration into a specific plant part, or translocation (among others). For example, I’m sure you’re aware that cotton is very sensitive to the broadleaf killer 2-4D (2,4 dichloro-phenoxyacetic acid). It’s outlawed in places where they raise cotton because of the extreme sensitivity. Not many people know that when you dissolve 2-4D in PVP (polyvinylpyrrolodone -spelling from memory) and spray a field rate of 10ppm on cotton you get a 15% yield increase. Of course PVP has an LD/50 of 100 GM/KG, and getting a farmer to correctly apply such a small amount with a very narrow window makes it impractical. Another was the use of 30%methanol/5%sodiam acetate to dissolve certain flavonoids from plant extracts. Look up the flavonoid apigenin cross-referenced with Bradyrhizobium japonicum. Acts as a bacterial genetic inducer.One aspect of my thesis involved foliar (as well as soil injected) application of apigenin dissolved in a bunch of different solvents. http://www.devileye.net/catalog/bird_cage/bradyrhizobium_japonicum_nodulation_inducing.html
    These guys did similar research in the late 80’s. My patent was rejected in 82, so it’s probably on page 109 at Google, but I digress. 4-carbon solvents are unbeatable on living material, like butanol. Heck sodium dodecyl sulfate would probably function as Adolfo’s brain solubilizer. SDS penetrates the skin and takes anything dissolved in it, with it (methyl parathion anyone?). One drop will do you. I used tagged sugar alcohols to determine translocation of proprietary chemicals into the harvested plant parts for EPA registration and patent work.
    I’m glad you brought this up. I’ll have to rekindle some memories looking into this.

  4. TIM CLARK says:

    Well, I read what I wrote and realized I didn’t make it very clear what we were doing and how it applied to this topic. We were trying to utilize a material that would 1. solubilize the chemical, and 2. to target our application to a specific plant tissue and the molecules they are made of, be it “melting” the cuticle, or plasmalemma, or the slime produced in the sieve cell tubes as a result of Dutch Elm Disease.

  5. E.M.Smith says:

    @Tim Clark:

    I think that the Deep Eutectic Solvent topic is a subset of what you are addressing. In particular, the use of things that are very common inside living cells, solids on their own at room temperatures (and above!), and seem to have a particularly catalyzing effect on some reactions and / or increased solubility of particular hard to dissolve life chemicals.

    @Adolfo:

    Um, ok…. I think I got lost right after “musical notes”… but I’ll try again ;-)

    Yes, the EU tendency to ban ALL use of an element if ANY use if found to be highly toxic is a bit daft. Then again, Cadmium poisoning is hideous ( it substitutes for zinc in a bunch of enzyme systems and screw up a lot of things, then your bones dissolve and you die from having your muscles and weight crush yourself…) This happened to a city in Japan where they made NiCad batteries and the effluent got into the local fishing… That’s when they found out how bad it was. (About that time I had bought a dozen 1 inch cadmium plated washers that are still in a bin in the garage. I just liked the slightly turquoise hint to the silver color of it and wanted to own some cadmium metal…)

    @Jason Calley:

    Oh Yeah… (Wonder if I can get a refund on 100 bottles of PeptoBismol ;-)

  6. R. Shearer says:

    Interesting! I’m going to have to read more.

    I’ve used ionic liquids for separation of volatiles.The ionic liquids, being ionic, have low volatility and selective solubility for certain species. Your post and comments are thought provoking.

    What did you have in mind with C1-C3 DES mixes? The alkanes are nonpolar so don’t interact like metals, salts or polar molecules and molecules that can hydrogen bond. If someone could come up with a way to separate polar species from water it would have a lot of valuable applications.

  7. Jason Calley says:

    @ E.M. Wonder if I can get a refund on 100 bottles of PeptoBismol

    Bear with me for just a moment…

    Last year there were some major forest fires near me and that night the air was hazy and stinky with smoke. My sinuses were all clogged and I slept with my mouth open all night. When I awoke, my tongue was actually black. I was amazed, astounded! That afternoon I told my daughter-in-law about it, and though I expected some variety of amazement from her as well, to my surprise she started laughing. “Did you take some Pepto-Bismol?” she asked. At that point I remembered that I had in fact, for the first and only time in my life, taken a Peptol-Bismol tablet during the night because my stomach was bothered. I just chewed up a tablet, swallowed it and went back to sleep. Apparently that will make your tongue turn black, and the smoke had nothing to do with it.

    It was news to me, and of course, I always enjoy looking like an idiot in front of pretty young women. Am I the only one uninformed about Peptol-Bismol and black tongues?

  8. E.M.Smith says:

    @R. Shearer:

    Nothing in particular in mind yet. Just looking at it and going Hmmm…. “Lots of ways to take it…”

    @Jason Calley:

    Never heard of that one before… Not seen it when using P.B. either. Must be a selective thing. Some co-factor or ?….

  9. Bruce of Newcastle says:

    E.M. – Been a while since I’ve been visiting your blog. Glad to see both metallurgy and organic chemistry in one post (I did organic chemistry at uni then became a metallurgist, heh!). Did I tell you I once froze 40 m3 of caustic solution because I forgot to dilute it from 50% to 30% before winter? We were wondering why a pump wouldn’t work when we tried to turn it on. Had to wait until Spring to get it out of the tank.

    And once I had a job where we were making a bismuth concentrate, as well as copper and gold, but we had to send it to a storage dam because the only decent market at the time (1980) was France, where they ate it. We had 3000 tonnes of effectively PeptoBismol stored hoping some other country would catch the same fad.

    I’ll segue into another alloy, bronze. We’ve just had Neil Oliver’s History of Celtic Britain pt 1 on our other government broadcaster.

    I mention it because of the posts of yours on the Bond Events. Neil Oliver doesn’t mention them but goes into some detail of the collapse of the bronze age in Britain in about 800 AD because of cooling climate. With some very interesting scientific evidence too. BE2!

    I know you are fascinated with everything (me too, there’s not enough hours in the day) but you might like to keep an eye on this stuff especially with our Mr Archibald getting even more pessimistic about the Sun.

    Oh, and the episode is a metallurgist’s dream. Ok, ok, I’m parochial.

  10. adolfogiurfa says:

    @Bruce of Newcastle (10:06:01) : Something for your fascination: Did you know that the addition of the atomic numbers of copper and tin gives 79: The atomic number of Gold?

  11. Bruce of Newcastle says:

    Adolfo – I can’t speak for others but for myself I am not actually interested in gold. It looks pretty but does not do much (though it is the best conductor). I worked in the gold room of a gold mine for a while, so this may be why. Though it was fun to electrowin the gold and then smelt the cathodes to doré.

  12. E.M.Smith says:

    FWIW I ran the PeptoBismol Tongue Experiment. Chewed a tablet just at bed time, woke up with a black top of tongue. Guess now I need to find out what causes it. (Is it, for example, a micro particle deposition of bismuth? Many metals give a black powder when divided finely enough…)

    I think part of the process is having it sit on the tongue for a while ( i.e. not washed off / rubbed off by food and drink. Usually when I use antacids I stay up for a while and nibble bland foods while slowly and steadily sipping liquids). I’d speculate it is a reduction product of some sort.

    @Bruce of Newcastle:

    40 cubic meters of anything frozen is hard to deal with, but caustic? Oh dear!

    I hope they didn’t get cranky at you as they waited for the seasons to shift ;-)

    The Iron Age Cold Period seems to be far enough back in time that the Warmers don’t feel compelled to erase it from history… Not enough people know about it for them to care, I guess… Yet it is a fascinating part of history. If you go even further back, there is a similar event with the Sea People invading most of the Mediterranean (and the Egyptians having a hard time of it, but managing to stop them…)

    The bottom line is that there IS a long cycle of about 1500 year average (though it looks to be divided into two nodal points at 1300+ and 1800 that only average to 1500…) and that seems to be driven by lunar orbital mechanics ( in that the shift of tides causes cold deep ocean mixing to shift on that cycle, leading to all the rest). But it is also ‘in sync’ with other orbiting things via orbital resonance; so may also happen in phase with solar changes (as we’re now having a cold sun period…) so some of the mechanics are still a bit unclear.

    As we’re now getting things like -20 C all day long in Europe and snow in Tunisia… I think folks are going to notice that it isn’t warmer ;-)

    FWIW, one thing I’ve thought about with this DES thing is the utility in making various confections… Instead of just using straight sugar, making a mix (that also tastes good!) could make for a smoother finish. I’ve had some ‘issues’ with frostings that were just not smooth enough (a bit of granulation left from the sugar). So perhaps a bit of two sugars (say glucose and sucrose) might fix that….

    I would ask “Why in the world did / do the French eat bismuth?”, but asking why the French do anything is risky business ;-)

    (Then again, why to the Nordics eat fish that’s been buried in the ground for months and why to Americans eat plastic food…)

    There’s been interesting stuff done with measuring metals in old bodies and mummies. IIRC it might have even been Utze (the Iceman) where they found deposits of arsenic and some other trace that indicated smelting of copper ore of some sort. Basically, the anthropologists have learned to to toxic metal forensics ;-) So now we can tell which guys hung out near the fire while the ores were being cooked…

    @Adolfo:

    So, you saying to mix them together and squeeze real hard? ;-)

    Interesting factoid, though…

    I’m with Bruce on the gold thing. It’s a nice metal, but not very strong. I like platinum and stainless steel much better… Then again, the ancestors were practicing Blacksmiths, so I’ve a family history of being interested in the practical weapons metals instead of the decorative ones…

  13. E.M.Smith says:

    @Verity:

    I thought you might find it interesting ;-)

  14. Jason Calley says:

    @ E.M.
    “FWIW I ran the PeptoBismol Tongue Experiment. ”

    Ha! I am glad to hear that it was not just me! As near as I can tell from a quick search, the bismuth subsalicylate in the tablet breaks down, then the bismuth combines with sulfur in the mouth to make black bismuth sulfide. Maybe a chewed tablet after a big meal of various sulfur rich brassicas and some sulfurous deviled eggs would be an experiment worth trying.

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