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Why mess around when you can get the real deal Triphenylphosphine oxide
98% ! Just sprinkle some powdered TPPO on the carpets and vacuum, poor fido goes into olfactory overload when he walk in.

Ferroce isn't harmeless https://en.wikipedia.org/wiki/... and viologen isn't a nice substance either http://www.sigmaaldrich.com/ca...

How come ferrocene gets a wikipedia page, but viologen has to make do with the Aldrich Chemicals page?

Ferroce isn't harmeless https://en.wikipedia.org/wiki/... and viologen isn't a nice substance either http://www.sigmaaldrich.com/ca...

The article doesn't say how much (in mg) needs to be loaded in to the pen, but here is one source at USP grade from a highly respected supplier, 200mg for $326.50 in the US. A quick google search suggests .3mg per injection so that 200mg should last quite a while.

I believe that the difference is hydrogen is soluable in many metals.

Since I've never heard of such a thing, please provide a link.

Note: given that hydrogen, even when diatomic, is smaller than Helium, it doesn't need to be "soluble" in metal to diffuse better.

Deuterium - Deuterium or Deuterium - Tritium.

Benzene doesn't hurt its use a fuel, and the total exposure is very very low when used as an antiseptic. The assayed benzene concentration in commercially available 200 proof ethanol is less than or equal to 1 ppm (basically the limit of detection of the test, so 1 ppm at worst). You'd be a fool to drink it all of the time, but drinking a few cL while hiking wouldn't be likely to hurt you, besides tasting like shit.

there are no legal sources of it

You were saying?

That's levomethamphetamine, the non-psychoactive enantiomer. It's present in several cold and flu products.

No, the molecule I linked to is dextromethamphetamine. Of course, you can get levomethamphetamine samples there if you want, too.

Oh, and there are a lot of hoops to jump through to [legally] obtain a meth standard.

Actually, it's a piece of cake. Here's one that you don't even need a DEA license to receive. You can get standards for analysis for most any drug easily. Of course, you're only getting g to mg, so there's no real avenue for abuse.

PFTBA is a liquid even if it were in a container on the ground in Death Valley on the hottest day of the year.

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

Even wikipedia gets it wrong by claiming that what is a liquid at any normal temperature measurable on earth is a greenhouse "gas". Perhaps they meant to say the vapor is a greenhouse gas? Someone should edit that article to correct that mistake.

Maybe wikipedia meant volcanic PFTBA. What's that you say, volcanoes don't make PFTBA? Go figure.

http://www.sigmaaldrich.com/catalog/product/supelco/442747u?lang=en&region=US

At STP:

Boiling Point is 352F, Vapor Pressure is 1.3mm/Hg, and Density is 1.88g/mL.

The vapor pressure is so low and the boiling point, density and molecular weight are so high that any vapor is likely to condense and sink to the bottom of the sea.

"... no known processes that would destroy or remove PFTBA in the lower atmosphere ..." is not the same as "no processes". Solar radiation and ozonolysis are likely candidates and are known to break down other classes of halogenated hydrocarbons, such as CFCs. Processes below the atmosphere, i.e. in the sea, are apparently not considered and gravitational condensation is outside their thought processes too.

The nitrogen in PFTBA has an unshared pair of electrons, which means it's capable of forming quaternary ammonium salts which are water soluble. Once it's water soluble, any number of chemical reactions could break it down.

A more likely worrisome scenario than PFTBA causing Global Warming is that a large enough earthquake, or a volcano, on a continental shelf could destablize a large field of clathrates and release more methane into the atmosphere than all the man-made natural gas leaks combined, including Al Gore's flatulence.

Sulfur dioxide and trioxide are potent greenhouse gases and form acid rain too. Think "atmosphere of Venus". Tons of both are released into the atmosphere yearly, much more from volcanic activity than from man-made sources, yet no one seems to be too worried about that problem.

Some would rather cry like Chicken Little about the juice we put into our capacitors than the juice we put into our car batteries.

I'm a little bit worried about Global Cooling.

Perhaps some spray cans of PFTBA would prevent it? We could put Al Gore out to a legume pasture and let him graze and fart.

I am much more worried about the dumbing down of the human race with all of the Global Warming alarmists leading us all to a dismal idiocracy.

Good job trying to hoax us once again, Slashdot.

That is all.

That is exactly what we need to terraform Mars! We need to send few tonnes of this stuff to Mars....

A lot more than a "few tonnes", I'm afraid. I'll also point out that the formula for this is C12F27N-- it has a molecular mass of 671-- that's fifteen times more massive than carbon dioxide molecules. So, per unit MASS it's only 460 times more powerful an infrared absorber than carbon dioxide.

SF6 is a better infrared-trapping greenhouse gas for Mars.

Chemical info here, by the way: http://webbook.nist.gov/cgi/cbook.cgi?ID=C311897

http://www.sigmaaldrich.com/content/dam/sigma-aldrich/structure1/050/mfcd00000436.eps/_jcr_content/renditions/large.png

For the naked eye, the ink would appear as a very pale cyan color. With a proper filter, everything would look very dark due to the filter removing 99% of the visible light, but the ink would show up with much more contrast. Effective long-pass filters do exist, e.g. Schott RG695 or RG715 for a 695 or 715 nm cut-off, respectively. There are plenty of suitable dyes. Probably you would want to have this filter only on one eye, otherwise the world around you might appear very dark.

The other theories that have been posted here make no sense.

Frequency-doubling needs extremely high intensities (like a high-power or focused low-power laser beam), which would render you blind. Moreeover, frequency-doubling requires proper phase matching, which boils down to the requirement of an exact combination of angle and wavelength.

Polarizers: it is not possible to turn unpolarized light into polarized light without throwing away half of the light. Once the light is polarized, the polarization direction can be manipulated with optically active materials, though.

A high-refractive index coating would not only change at the Brewster angle, it would make the cards much more glossy as seen from any angle. It is not possible to make the refractive index change dramatically within a short wavelength range without changing the absorption as well, so the glossiness would appear in visible light as well.

A phosphor coating would not work for several reasons: phosphors do not emit the phosphorence in the same direction as the absorbed radiation; they always convert from short wavelengths to long wavelengths, and the phosphorence light would be completely out of focus.

Chlorine is normally supplied in commerce in liquid form in a steel cylinder. From lecture bottles up to rail cars.

http://www.sigmaaldrich.com/catalog/product/aldrich/295132?lang=en&region=US

When I worked with chlorine I always weighed it. Generally by putting the storage container it was supplied in on a scale.

I never saw anyone count chlorine atoms. The idea is preposterous.

So how much more expensive is the second, "smoothing" phase than the original production phase?

It's another wet-chemistry phase. It's no more expensive than the first synthesis step. But each step of course adds to costs (in terms of manpower, chemicals needed, etc.).

Similarly, adding the lipid layer is just a a ligand exchange: you mix the quantum dots with ligand in the right solvent mixture and they become coated. Simple in principle, not too complicated in practice, but it adds another step to the process.

how much do the products of each of those phases currently cost

Quantum dots are fairly expensive, but they are similar in cost to speciality chemicals that don't have industrial uses and thus don't benefit from economies of scale. Some examples from companies that currently sell quantum dots:
Invitrogen 4 ml of 1 micro-molar QD solution (~15 mg of qdot solids) for $335 ~ $22 million/kg
Sigma-Aldrich CdSe QD, 5mg/mL, 10mL solution for $399 ~ $8 million / kg
SpectrEcology 50 mg CdSe/ZnS QDs for $449.00 ~ $9 million / kg

For comparison, ubiquitous chemicals like gasoline are ~$1/kg, common chemicals like acetone (reagent grade) are ~$30/kg, high-purity semi-rare materials (e.g. pure selenium) are ~$1,000/kg, and speciality chemicals (for which there is no industrial need) are typically $100-$1,000 for a 500 mg quantity, which means $1 million / kg. As you can see, it is much more expensive to synthesise a speciality chemical (basically requires a trained chemist to manually do a small-scale lab synthesis for each batch), as compared to industrial-scale manufacturing.

There's no doubt that quantum dots could be made more cheaply if there were a real need for them. There are huge challenges in terms of how to scale-up the synthesis, but nothing that couldn't be addressed with clever chemical engineering and automation.

Where the HELL can you buy a toxic substance like carbon monoxide, we asked. Not his problem but he wouldn't sign off until we did. After finding out that it was illegal to ship the stuff, and that there was no local supplier,

Not that I don't sympathize with your predicament, but carbon monoxide is routinely used in chemistry labs around the country (I did in graduate school). Call up Aldrich and they will happily ship you just about any chemical.

That being said, carbon monoxide has the potential to be extremely toxic and should not be used without proper training and safety equipment. That's why you have carbon monoxide detectors!

The old chemistry sets of the days long past were particularly nice for their easy-to-read and understand instructions for doing things, which was nice for kids to learn. But these days, most of those instructions are pretty easily found on the internet.

Vat-grown, or printed, meat products are produced using the same basic techniques as other forms of printed tissue culture. Tissue engineering of this type was first developed for medical use in the production of autologous tissue for organ replacement. However this sort of tissue culture was soon found to be useful for the direct production of meat for food on spacecraft and habitats in deep space. See bioforgery.

To achieve the goal of meat production, muscle and other flesh cells are grown on a specially constructed biopolymer scaffold, which replicates the natural extracellular matrix found in living animals. This scaffold is generally printed using a rapid 3d printer device, although several other related techniques such as foaming and self-assembly are also used. Cultured cells are then implanted into the scaffolding, and these cells are induced to bind together into muscle-like or vascular tissue. Once the meat block, known as `slab', is established, the tissue is supplied with nutrients and allowed to grow by as much as 400% by volume before harvesting. To ensure the slab has a healthy texture it is stimulated into regular contractions, simulating exercise; the slab is attached at each end to strain gauges to measure the force of contraction. Each slab is connected to a generous supply of nutrient fluid often closely resembling blood.

Matter compilers in meat factories to produce foods. So, this looks like an interesting area of thought to explore further. Starting with cell culture techniques would be the smart thing to do, then confirming that we can identify particularly nutritious cells, and then working on some tissue growth techniques. Maybe this will start with burn victims?

Artificial cells, tissues, organs compilation,
Background notes on tissue engineering,
Engineering human tissue (paper),
An odd government website,
Obligatory Wikipedia article linkage,
Organ printing,
This source is claiming lab-grown meat in five years,
Fetal farming (what?),
New-Harvest.org for bringing cultivated meat closer to reality,

To answer you question :

1. 200 proof isn't that expensive, and we get it at a fraction of that cost. Denatured would be cheaper.

2. no more than 10-20ml is needed. (half a dollar's worth).

3. using ethanol as a disinfenctant is common practice in microbiological labs (my workplace). Typically, 70% diluted with ddH2O is used, but I'm a bit lazy.

4. propanol (rubbing alcohol, isopropanol) is a household disinfectant that can be picked up at Duane Reade. hope this answers your question.

Who needs them?

http://www.sigmaaldrich.com/catalog/search/Product Detail/ALDRICH/347795

Also available at Fisher, though I dont have the patience to deconstruct their search form into a url...

yeah, but nearly everything is toxic in sufficient doses, including water!
http://en.wikipedia.org/wiki/Water_intoxication
http://news.bbc.co.uk/1/hi/world/americas/6261509. stm

For some perspective, here's an excerpt from the MSDS for table salt:

Sodium Chloride (NaCl) free-flowing powder

Skin Contact: May cause skin irritation.
Skin Absorption: May be harmful if absorbed through the skin.
Eye Contact: Sodium chloride (NaCl) in contact with eyes can
cause irritation or redness due to abrasion.
Inhalation: May be harmful if inhaled. Material may be
irritating to mucous membranes and upper respiratory tract.
Ingestion: May be harmful if swallowed.

http://www.sigmaaldrich.com/catalog/search/Product Detail/FLUKA/50127

Also, it can be hard to obtain (search for "bona fide institution" in this http://www.cs.rochester.edu/users/faculty/nelson/c esium/cesium_faq.htmlpage!

As a poor-person's alternative, try an alloy of
22% Sodium 78% Potassium (by weight)
http://www.sigmaaldrich.com/Brands/Fine_Chemicals/ Product_Focus/Suparna/Sodium_Potassium_Alloy.html this alloy is liquid down to -12C

If you have the inclination
(THIS IS DANGEROUS!),
you could probably make it at home by electrolysis from the hydroxides
(YOU COULD HURT YOURSELF OR SOMEONE ELSE VERY BADLY!)
http://www.sas.org/E-Bulletin/2001-10-05/chem/colu mn.html
(THIS IS DANGEROUS!)

Anhydrous ethanol used for industrial processes may be "spiked" (denatured) with methanol to discourage consumption but this is never the case with reagent grade "absolute" ethanol. When a chemist needs ethanol for an experiment and ONLY ethanol, that better be all that's in the bottle.

no, no. Of course white phosphorous is even more reactive and may even ignite itself when in contact with oxygen. But red phsphorous burns pretty good, too. makes a lot of smoke as well (good for smoke bombs, the smoke forms phosphoric acid thogether with the air humidity though) and together with potassium chlorate (KCl03) it makes nice explosions.
here is a link to a chemicals supplier. notice the risk statements: R11 = Highly flammable, R16 = Explosive when mixed with oxidizing substances

The parent post asks what could be used for staining that isn't a mutagen. One possibility is Blueview. The image of the kit on the discovery site shows the DNA stain with a label "Blue DNA Stain", which is consistant with a product like Blueview being used.
From the Sigma Website: BlueView is a quick, safe alternative to ethidium bromide staining for nucleic acid electrophoresis. BlueView can be used directly as the running buffer and in the gel for instant staining of the bands of nucleic acids during electrophoresis, visible in ambient light.

Sigma Aldrich specializes in high purity chemicals

VWR Scientific is one of Fisher Scientific's main competitors

Spectrum Chemical is known for having good sales on their chemicals.

And, last but certainly not least Lab Safety and Supply can take care of all of your safety needs!
As a chemist who has had the misfortune of experiencing chemical burns due to my boss' stupidity, I can't stress the importance of protecting yourself enough! There is no such thing as overkill when it comes to safety!!!!

Also, be aware that I have only ordered from the afformentioned companies through my job...I have no idea what kind of information they will require before they sell to you...I do however know that ordering certain combinations of chemicals together or within a short time frame will get your activities/purchases reported to the authorities.

It may also be worth noting that there is no such thing as anonimity in the chemical industry...AFAIK, chemical companies are required to put "taggants" in to some, if not all, of the chemicals that they sell..."taggants" are inert compounds that do not affect the properties or behaviors of the chemicals into which they are place that will allow authorities to trace the manufacturer of the chemicals if they are used in an illicit manner...

That these scientists downloaded their instructions off the net and used ordered the sequence mail order is not at all the shock that this story portrays it as. Virtually every common technique in molecular biology can be accomplished with a pre-made "kit" from one of several major vendors (e.g. Sigma, BioRad, Qiagen). These kits contain all the necessary reagents and instructions for completing the procedure. Most of the companies that produce these kits also post the instructions on their websites in case you loose the printed copy. Any trained molecular biologist would have a pretty easy time recreating the "kit" from the directions and the ingredient list.

As for getting DNA by mail, that's standard practice at most research labs I've been involved with. It's more expensive than producing it yourself, but a hell of a lot more convenient. Many universities even have their own, "in house", sequence generation facilities that labs interact with by, you guessed it, inter-departmental mail.

I'd say the poster of this story was taken by the shock value of these statements (and perhaps they are more shocking in our terrorist-paranoid times), but in reality, there's nothing to be suprised by.

Theo is missing some elements for the table, in case you have any spare europium (in a proper container, of course) lying about.

You can get Europium Oxide from Sigma-Aldrich Chemicals. About $162 for 10g. It's an oxide of the element, but it's stable.