elementcollector1

Carbon fibre is exactly what one should avoid to absorb shocks. Glass fibres aren't good neither. You might try aramide fibres, but they're good only to spread a very local impact as a bullet-proof vest.

 

The real material to absorb shocks is polyurethane. Most resistant, little rebound. If for some reason its shape does not fit you need, you may try a polyamide rope, but it absorbs only one shock through irreversible strain.

Very odd. If you look up 'powerbocking', most of the stilts used there are either carbon fiber or fiberglass. Additionally, prosthetics are leaning more and more towards carbon fiber (and also titanium) nowadays, with some interestingly superhuman side effects (faster run speed, higher jump, etc.)

Additionally, I found out about 'leaf springs', which seem to be very similar to the goal I'm trying to accomplish. They're made of high-carbon steel, and you'd think that would transmit mechanical energy rather than absorb it.

According to my research, sorbothane is polyurethane, just a different form. This makes sense, as the video from the original site states that it was developed from an existing polymer to simulate human skin (which is apparently very good at dampening and absorbing shocks).

This topic is fascinatingly dull.

The OP says "proven by the known laws of physics" over and over again, as though that validates everything. The 'known' laws of physics are not the 'definite' laws of physics, in the sense that they haven't been irrefutably proven - there are several exceptions to what we consider the 'known' laws. Take the ether of the late 20th century - everyone was damn sure it existed, and spent countless experiments trying to find it. They didn't.

Until you start providing real science instead of claiming that your pseudoscience is supported by "the known laws of physics", we'll have to dismiss you as another soapbox preacher. (Hint: the current scientific model focuses on disproving or finding exceptions to a theory, instead of proving it.)

My application is an experiment to see if this stuff will cushion shock to an appreciable level while being dropped from different heights. For example, if I were to wrap an egg in a quarter-inch thick layer so that the egg couldn't move on its own, and dropped the setup from 50 feet up, I would hope that the egg remains intact. If this works, I'd like to see if this applies to humans, e.g. if a human could survive falling from higher distances with a thick pad of this stuff and a few other bracers on.

This is why I mentioned the carbon-fiber/fiberglass setup - my hope is that this would be a sort of leg brace that would also absorb the shock (there might be pads of sorbothane on this as well). I was inspired by the carbon-fiber flat pieces that are attached to an amputated leg - apparently with two of these, humans can jump/fall 15/20 feet and not be hurt.

My best bet right now would be to conserve on the sorbothane until it's only where it's needed, and instead place rubber padding everywhere else.

Natron is sodium *carbonate* decahydrate.

I don't think all those sodium compounds are necessary - while it would do the trick, either the natron or the baking soda would do perfectly well by themselves.

However, if you're shooting for a green solution (which means copper is still present), the salt may just donate its chloride ions to the copper ions from the dissolved copper sulfate to create the tetrachlorocuprate ion, CuCl₄^-. The precipitate from reacting copper sulfate with natron or baking soda would be sky-blue copper hydroxide.

If you put enough baking soda/natron in, there will be no copper sulfate in solution. Copper hydroxide might dissolve in the water to some extent, but this would be extremely limited - on the order of 0.01g/L!

What exactly is the 'goal' here? The copper hydroxide? The green solution?

Not quite what I had in mind, but it'll work very well nonetheless.

EDIT: Checked the site, and I would have to call for pricing nonetheless. Where do you order this stuff cheap? There must be some sort of Chinese manufacturer somewhere... Everywhere I look a 12"-12"-1/8" sheet is around $25 at the cheapest!

Back to my original question: Just how shock-resistant is a mixed-layer composite of fiberglass, carbon fiber and resin? Would it be better in terms of absorbance to just use one or the other? Does the resin factor in?

Didn't we have a topic of this already on the SciMad board?

Check there, we gave you a pretty in-depth walkthrough - but we'll need to know the concentration of your HCl!

I'm wondering how best to make a material, say a thin bar, that has very good shock-absorbing properties and low mechanical stress. I was thinking a layered mix of fiberglass and carbon fiber, bound together by resin, and I was wondering what some more experienced engineers would think of this.

Steel is always better for crucibles, unless you can get nickel or the two holy grails, graphite and platinum.

EDIT: Also, I've seen solder / lead ingots at some local hardware stores - one or two of those could easily make 2 or 3 castings of this size.

Pt/Ir alloy would be excellent for electrolysis, as it's pretty much immune to corrosion short of aqua regia.

(Do you have a source? I might look into buying some of this.)

@ajkoer:

So far, every claim thrown forward by you has been debunked by basic chemistry and physics.

When are you going to accept that your hypotheses are false?

Not as in, "skeptically claimed" or "not likely". As in, entirely, completely, irrefutably false.

You've tried this odd tangent three times now - twice on ScienceMadness, and once here. What exactly does this topic mean to you that you're willing to continue three times after others have told (and proved) that it's wrong?

Yes, this is possible.

A solar panel + ion thruster would be a feasible way to power a space ship.

 

I googled around a bit, and found at least one satellite, called TacSat-2, that has exactly that (launched in 2011)... so your idea is actually already being used. In the list of specs, you should search for the Hall Effect Thruster.

I thought the Hall Effect had to do with electromagnetism, can someone explain this to me?

DPD is an abbreviation of diethyl-p-phenylene diamine.

Look it up!

We've seen (and mentioned) that video several times throughout the thread. It is an interesting one, but an ever-present problem is how to collect the sodium metal at the end.

As it turns out, those requirements were a little too extravagant (as you may be able to tell). I've narrowed down the requirements to a few specifics:

-Fairly small (within the size of 3" by 8" by 3")

-Battery-operated

-Can levitate sideways?

A bit like this, but with the levitation extending out the barrel instead: http://hackaday.com/2012/10/11/hackadays-portal-gun-actually-levitates-a-companion-cube/

As you can see, the main part of the levitation device is tiny, measuring in at just about 2" by 1.5". But the levitation, as noted by the article, is weak - the device cannot be moved without disrupting it.

The prop I have in mind also has three claws and a hollow barrel, so would it be possible to take more than one of those levitation toys and attach them to each claw (and possibly one in the center)? I don't think that each device would interfere much with the others, but then again, I'm new to this kind of engineering.

Additionally, the lowest expense I could find for just 1 of these was $20 on Amazon. Sites like ThinkGeek offer even more expensive versions, so that's a no-go. A cheaper solution would be welcomed.

Thorium-plasma battery.

Interesting! If this works, that is.

and...?

When boiling the solution:

pH goes up - H2SO3

pH goes down - H2SO4

Just another thing to add to the test.

If anything, boiling a solution of H2SO4 lowers the pH - the water boils off first, leaving a greater concentration of H2SO4 (to a point) behind.

Again, maybe that is what happened, but it's not scientific to make up a story - which you pointed out in the story.

And besides, making up a reaction-mechanism, however wrong it may be, is the first step to pinning down the real thing. Who knows, maybe this hypothetical chemist got it on the first try. Maybe not. We'll need to think of some tests to prove that the originally proposed reaction, as it stands, is wrong, and that a different reaction would be better. I'm interested in cutting the Mg content in half, but I still don't understand what that would do. Another test would be to simply heat up KOR under solvent and see if any K forms.

How large is the cellar? If it's small enough, I would recommend the classic DIY trick of placing it in an aluminum container filled with a solution of baking soda - works every time for my pure silver bar.

Corrosion on silver (and also on sterling silver) is due to the formation of AgS from sulfides in the air. To protect your silver, I would keep it away from sulfur-related items, such as synthetic vulcanized rubber and such, and storing it in another good container (regulate the air that it touches).

These are all guesses (I'm too young to own silverware!) but I'm sure they should help.

From prior experience with nickel-plated magnets, nickel has excellent resistance to hydrochloric acid, barely dissolving at all.

As for what it's weak against, I'd try nitric acid or even aqua regia - those will dissolve just about anything.

Ahaha, no. Not the last part, by any means - no one has found a way to make the tertiary-alcohol synthesis work for Na. And I'm not sure about the decomposition part - that would require testing with pure potassium tert-butoxide or some such, as opposed to the usual reaction mix.

As for the story, I admit it'd be humorous, but unless I see some citations, I'll think of it as nothing more than a story. Chalk it up to scientific skepticism, but something you just came up with in your head does not make itself true.

Also, isn't it a bit redundant to synthesize Na metal from K metal? Most experimenters want Na for the drying power or the reaction in water, and K is better in both respects. As for element collectors, they might go after Na from K, but would probably go with Na from Mg or electrolysis first.

The formation of sodium from electrolysis has a few problems with a simple, yet difficult solution. The first is the 'splattering' that tends to happen when NaOH is melted, and this is by no means fun. The second is the sodium immediately oxidizing at the surface once formed, resulting in decreased or no yield. Both of these could be solved with an inert atmosphere - but setting that up can be a challenge in itself. Sodium from Mg via the reaction between NaOH and Mg metal can be viable only if, once again, there is no oxygen or moisture in the reaction container. Nighthawkinlight, who seems to have 'pioneered' this method, simply used a closed steel pot, which could be modified by an inlet and outlet tube and hooked up to an argon tank (the lid would also possibly need to be modified to seal better).

'Remember, good science always wins in the end'

I attempt to educate myself through actual testing - show me a test to prove some calculations, I'll do it and post the results. There are plenty of papers out there that can claim anything they want, but I would much rather see what they're talking about firsthand. To be honest, I did 'jump the gun' on the nascent/chemisorbed hydrogen, and for that I apologize, having no background on the subject but your previous posts and subsequent reactions.

I'd be interested to look at the reaction between NaCl and K, but would first have to check if the reaction is energetically favorable in terms of enthalpy. If it does work, and one can narrow down a good source and repetition of tert-butanol and K formation, then it would be a much simpler and possibly less dangerous path to sodium than I have seen. I wonder if such a reaction could work for lithium, or even rubidium and cesium as well...

Sigh... And one search on YouTube would have saved you all the trouble:

There you go. Not nearly as good as a decent circuitboard, but the point is it works.

Dear AJKOER:

Just because your reactions met with negative feedback on one forum, does not mean you can post them on the other. There's a reason we don't believe in this 'nascent hydrogen'.

Seriously, woelen even suspended your account because you wouldn't stop postulating. Does that send any message to you? Maybe one about hijacking threads with your theories?

Besides, this thread is about sodium. So unless you have a post to make about sodium, move your post to a new thread, titled 'Nascent Hydrogen in K Production' or something, not an already existing thread about a similar element.

Actually first I asked Yahoo Answers and I got it wont effect, but I wanted to make sure more so I copy-paste it here for more information about it. Thanks

 

I want to know all the carcinogen substances and toxic ones, can you help with a website? Thanks!!

 

So I must not worry, right? It was my first exposure for this substance. The amount was too little, barely the size of the upper part of the pointer finger (I mean if you open your hand and turn it around, the upper part of the pointer finger, if you want the third hinge). Thanks!!

Good luck getting *every* carcinogen - there must be millions! And that's what we know: There's probably billions more that we don't.

I found this with a quick Google search:http://www.cancer.org/cancer/cancercauses/othercarcinogens/generalinformationaboutcarcinogens/known-and-probable-human-carcinogens