1

Chemistry / Why did my charcoal turn white in a fire?

« on: 08/06/2011 03:48:54 »

Fantastic, thanks. Makes sense.
I guess I was naive enough to think that the charcoal was actual charcoal!

2

Chemistry / Why did my charcoal turn white in a fire?

« on: 01/06/2011 16:01:03 »

Joel Hillman  asked the Naked Scientists:
   
Dear Naked Scientists...

I've been a little bit confused about something lately, in my house, we have an enclosed fireplace, which burns very hot.

I had some charcoal for sketching, and being the empiricist that I am I put some in the hottest parts of the fire, to see what would happen.

To my surprise, instead of combusting as I had expected it to, it turned an ashy white, if you'll excuse the pun. 

It has a similar weight, texture and size, but it turned pure white. I snapped the block in half and it was white inside as well as out, so it wasn't just transfer of ash.

My first thought was some sort of allotrope or something, but I don't think carbon has any like this, so I don't think that's it... I was wondering what you think?

Why did this charcoal turn white?!

Thanks

Joel 

What do you think?

3

Cells, Microbes & Viruses / Why don't human red blood cells have nuclei?

« on: 01/11/2010 01:30:05 »

Joel Hillman  asked the Naked Scientists:
   
Hello brilliant scientists!

I know human blood cells don't have nuclei, but from memory, reptiles do - I haven't looked into it, but I figure its so more haemoglobin can be jammed in. So why do other animals have nuclei, but not people?

Thanks

-J

What do you think?

4

Cells, Microbes & Viruses / Can parasites extend their host's life?

« on: 23/10/2010 06:57:14 »

I suppose they aren't really the same, and I guess that does push it into commensalism, but what you said about living without, but being benefited if it's there.

The reason I said parasite was that I specifically meant in a parasitic kind of setting, ie not a cleaner wrasse and a shark, where the two can live apart, and not like lichen, where they are dependent upon each other to live, but something that specifically offers a trade - living as a parasite, while extending the lifespan or some such. My own (somewhat pale, in comparison with others I imagine are on here) knowledge of medicine and biological sciences say that there isn't a clear method or path for this to occur, I mean I, for one, cannot see a clear way that an organism could do this, but it does seem logical for it to happen. I'm not necessarily saying that it does, just that it would kinda make sense if it did.
The reason that I ask, despite this is that my knowledge of the world, much to my dismay, is not complete, and thus I must ask other members of the scientific community for help.

I guess my vague ramblings aren't helping much, but that's kind of what I was getting at...

5

Cells, Microbes & Viruses / Can parasites extend their host's life?

« on: 22/10/2010 13:17:36 »

That's not actually parasitic, that's really more of a symbiotic relationship than a parasitic one, I would think. ie the bacterium benefit by having a share of the food, they have a place to live etc., but the body also digests some, and is given the opportunity to make use of certain substances which it might not have otherwise been able to, etc.

I know that many parasites don't kill their host, and I know that pretty much the definition of a parasite is that it gains at the expense of the host, but does anyone know about any parasites which provide a benefit their host, as well as being parasitic?
I also realise that this may push them more into the symbiotic relationship group, but the concept is still the same.

6

Cells, Microbes & Viruses / Can parasites extend their host's life?

« on: 20/10/2010 10:30:03 »

Joel Hillman  asked the Naked Scientists:
   
I was watching a great little sci-fi show a little while ago which had an eight-legged endoparasite, which once inside the body suspended the body's descent into senescence and extended the lifespan indefinitely.

While this is a little too far into the realms of fiction, I was wondering if there was any science to be found? I know there have been a few studies on helminth therapy and the like, that's not what I mean, but I was wondering - is there actually any truth in this?

It does make a vague sort of sense, if the parasite's host lives a longer life, with less disease and faster healing, better health etc surely this provides a very large benefit for the parasite? I mean if it lives off a host, and the host lives indefinitely - then this has a clear advantage.

Thanks very much

J

What do you think?

7

Physiology & Medicine / Why is sleep deprivation fatal?

« on: 22/07/2010 10:30:02 »

Joel Hillman  asked the Naked Scientists:
   
Hello Naked Scientists,

I've heard humans can last approximately 10 days without any appreciable sleep, and though symptoms set in much earlier, it is at this point one dies. The way it was described to me was that the neurons begin regenerating, thus killing the person - I interpreted this as the neurons begin to reform over the top of themselves. I'm not a doctor yet, so I was wondering if you'd be able to help me with this: How does one die from lack of sleep? My idea before this was simply that the body is run down. What would happen to neurons in a situation where no sleep was achieved?

I had one last question: I've spent some time volunteering in an orphanage in India, and while I was there, for a period of about one week, I had virtually no sleep, due to noise disturbance. At the end of that week I began to hallucinate, which was very unpleasant. So, my question is this - how and why does lack of sleep cause hallucinations? And I'm not just randomly linking symptoms with stimuli, hallucination is (as far as I can find) a symptom of sleep deprivation.

Thanks so much
-J

What do you think?

8

Physiology & Medicine / Why is the cartilage holding the trachea open C-shaped?

« on: 15/05/2010 23:30:02 »

Joel Hillman  asked the Naked Scientists:
   Why are the 'C' shaped pieces of cartilage holding the trachea open 'C' shaped? Why not just rings?

Thanks!

-J
What do you think?

9

Chemistry / Does anyone have any tips on memorising the entire periodic table?

« on: 15/04/2010 06:20:37 »

There must be a few different versions, to tell you the truth, I've never heard the out of order one... and now all I can think is: "Theeeeeeeres Hydrogen, Helium, Lithium and Beryllium...".
But mnemonics are one of the best ways, 'fat cows bend in angles'. I like it!

10

Chemistry / Can you turn a liquid into "marbles"?

« on: 15/04/2010 06:17:35 »

haha good ones you two!

Well, like I said, marbles, as in the glass spheres, nope. not a chance.
But as far as the spherification or polymer spheres, then thats different. but spherification that large would be nigh impossible (in my opinion).

So insofar as doing what he says, then as Bored Chemist says, the video is 'Bollocks' (best word ever by the way! it doesn't get used enough here is Australia)

11

General Science / Why are scientists so sure that the light barrier is impenetrable?

« on: 15/04/2010 05:08:20 »

There was something else I forgot to mention, if you went faster that the speed of light, for the same equations:

t_v= t₀/√(1-(v²/c²))
if you had say
t_v= t₀/√(1-((c+1)²/c²))
(which is only 1m/s faster than c, not very much faster!)
√1- (c²+2c +1)/c²
which I work out to be √-0.000000007
 Then you would end up as √-ve. And square rooting a -ve number is a massive no-no. Those are two of the most important rules, never divide by zero, and never square root a -ve number!! (unless you want to go into imaginary numbers and 'i', which still wont make you go at 3x10⁸m/s)

And of course, the same goes for the other equations, as they all have √(1-x), with x being the speed division.

I would be inclined to agree with Krytie, there are far more useful things to be doing with our time than trying to travel faster than light. Though not necessarily spending it making wormholes!

12

Physiology & Medicine / What is the treatment for night-blindness?

« on: 14/04/2010 04:17:18 »

I think if its genetic, then there may not be a particularly easy way to cure it, I mean the same with other genetic 'faults', theres not really much you can do about it. If its a vitamin deficiency or toxicity, then thats different.
So, if like you say, and it IS genetic, and its a congenital problem with the rods in the eye, then sorry... not a huge amount can be done really, at least that I know of

13

Chemistry / Does anyone have any tips on memorising the entire periodic table?

« on: 14/04/2010 04:08:00 »

The periodic table of the elements song is easy to find and is pretty effective too.
Its pretty much just the elements put to music!

14

Chemistry / Can you turn a liquid into "marbles"?

« on: 14/04/2010 04:04:45 »

well... I don't know if I would do it that way, but there are ways you can do it, it's apparently a culinary delicacy, somewhat like caviar. Its called spherification, though that large is a bit unfeasable. You normally use Calcium alginate, rather than acetate though.

I suspect what he has done is get those water-absorbing polymer spheres you can buy from florists, they hold water into jelly like spheres, very soft, very fun to play with.

I don't know about his explanations though, I don't think they're particularly accurate. and the font and music do nothing to add credence!

Sorry to contradict you Bored Chemist!

15

Chemistry / What is the rarest element in the universe?

« on: 14/04/2010 03:57:47 »

I would say the last few on the PT, as Ron pointed out. These don't really appear in nature, they're made by slamming atoms into each other,  so this wouldn't be too common without scientists manipulating things with accelerators and whatnot!
so the ones on the bottom row (not the Actinides and Lactinides) the actual lowest row. These atoms are extremely unstable, especially the larger (the larger the atomic number, the larger the atom), which last only for miniscule amounts of time

16

That CAN'T be true! / Could we send nuclear waste into space?

« on: 14/04/2010 03:51:30 »

Ok, nuclear power, if prepared and utilised in a safe manner is, in my opinion, one of the best power sources yet, and until fusion power gets up and running, it has my vote!
So basically, the thing about nuclear power is it gets the bad views from pop culture, and things like the simpsons dont help - three eyed fish and whatnot.
basically, its only dangerous if people are really foolish and dont pay attention, though the same can be said for coal-powered generators, in Australia a few years ago, something fell into the path of one of the rotors of one of the larger generators in the state, the force that it carried caused the entire system to explode, raining down pieces of iron for kilometres around. fortunately it was in an isolated area.

Things like Chernobyl happen when people are careless, not because of the nature of nuclear power, but this is irrelevant, its just my rant about people being scared of radiation and nuclear power.

The thing about the waste is that there generally isnt as much produced as people would think. In Australia, near me, theres this great research facility called ANSTO, they work with tiny amounts of uranium (dont actually produce power unfortunately) but theres this 'new' compound called Synroc, which can imobilise the radioactive waste and lock it away until it breaks down into harmless atoms, which would be the best (in my opinion) way to deal with it

some info on it can be found here: http://www.world-nuclear.org/info/inf58.html

17

That CAN'T be true! / Person Using Chi Energy !! it's Impossible ?!?!

« on: 14/04/2010 03:31:10 »

because the fact that someone believes something truly, is not something to be ridiculed.
well, i dont think so, and anyway, this is not the forum (if you will excuse the pun) to discuss such maters

So if you went into a boxing ring, you wouldn't expect to get punched? Just because someone believes in something does not make that something sacrosanct. If you believe in that stuff and keep it to yourself, well, that's fine - you're allowed life choices, naive as they may be. But if you express it in a public arena, especially on a science forum, expect it to be treated with the derision it deserves.

I don't go to boxing rings
but I see your point, perhaps I should stay silent in such matters.
I guess that you're right when you say that its not sacrosanct, and perhaps its not...

18

That CAN'T be true! / Why can't a motor hooked up to an alternator provide free power?

« on: 14/04/2010 03:25:28 »

I would agree, despite constant quests for perpetual motion machines, there is no way you can get a free lunch, there are always external factors which make it... not!

19

General Science / Does science recognise psychic abilities?

« on: 14/04/2010 03:21:28 »

I like this:
http://xkcd.com/373/

20

General Science / Why are scientists so sure that the light barrier is impenetrable?

« on: 14/04/2010 02:29:13 »

ecause if you factor the speed of light into the equations:
1. for observed time:
t_v= t₀/√(1-(v²/c²))

2. for observed mass:
m_v= m₀/√(1-(v²/c²))

if you subbed v (the speed of the object) into the equation as c (ie it's traveling at the speed of light c, ~3x10⁸) , you'll get 1/1 = 1, then you'll have √(1-1) = √0 (and that doesn't go down too well with physicists and mathematicians) but is generally accepted as being zero, so you would be dividing by zero, which is a big no-no. NEVER, EVER divide by zero!

so you get an undefined answer for both mass and time

Oh, and then there's length:

l_v = l₀ x √(1-(v²⁄c²))

which would end up as l₀ x 0 = 0
length of zero, undefined mass and time...
not fun!