Nuclear fusion is a reaction in which two or more atomic nuclei are combined to form one or more different atomic nuclei and subatomic particles (neutrons or protons). The difference in mass between the reactants and products is manifested as either the release or the absorption of energy. This difference in mass arises due to the difference in atomic binding energy between the nuclei before and after the reaction. Fusion is the process that powers active or main sequence stars and other high-magnitude stars, where large amounts of energy are released.
A fusion process that produces nuclei lighter than iron-56 or nickel-62 will generally release energy. These elements have relatively small mass per nucleon and large binding energy per nucleon. Fusion of nuclei lighter than these releases energy (an exothermic process), while fusion of heavier nuclei results in energy retained by the product nucleons, and the resulting reaction is endothermic. The opposite is true for the reverse process, nuclear fission. This means that the lighter elements, such as hydrogen and helium, are in general more fusible; while the heavier elements, such as uranium, thorium and plutonium, are more fissionable. The extreme astrophysical event of a supernova can produce enough energy to fuse nuclei into elements heavier than iron.
In 1920, Arthur Eddington suggested hydrogen-helium fusion could be the primary source of stellar energy. Quantum tunneling was discovered by Friedrich Hund in 1929, and shortly afterwards Robert Atkinson and Fritz Houtermans used the measured masses of light elements to show that large amounts of energy could be released by fusing small nuclei. Building on the early experiments in artificial nuclear transmutation by Patrick Blackett, laboratory fusion of hydrogen isotopes was accomplished by Mark Oliphant in 1932. In the remainder of that decade, the theory of the main cycle of nuclear fusion in stars was worked out by Hans Bethe. Research into fusion for military purposes began in the early 1940s as part of the Manhattan Project. Self-sustaining nuclear fusion was first carried out on 1 November 1952, in the Ivy Mike hydrogen (thermonuclear) bomb test.
Research into developing controlled fusion inside fusion reactors has been ongoing since the 1940s, but the technology is still in its development phase.
By comparing hot, cold and soundfusion (sonofusion) power which one yields more energy and more favourable for future power generation?
well as far as i know sonoluminscence are generated from collapse of bubble when excited by ultrasonic sound wave, thus light are emmited from it, and it is...
1.with the hot and cold fusion under experiment level now, would power from sound fusion provides equal or more power and economic value if it has been successfully researched?
2. what is the difficulty faced in building a commercial sound fusion generator?
3. Future of sound fusion...
I have a graph here separated into 5 different parts (A-B, B-C, C-D, D-E, E-F) It is a curve going upwards...I just need to know how to calculate the heat of fusion of the substance using the curve in the graph...I can use the formula and calculate the heat of fusion for each little piece...
well, i stumbled across this link:
http://jlnlabs.imars.com/cfr/index.htm
it seems unbelievable that something is really happening in there...
then i started looking around the net to see what other people think:
http://en.wikipedia.org/wiki/Cold_fusion...
Okay deuterium consists of 1 proton and 1 neutron and tritium consists of 2 protons and 1 neutron, now if one atom of each, smash together that forms an atom of Helium which consists of 2 proton and 2 neutrons, a 3rd neutron is created and released, how does the 3rd neutron come about?
[SOLVED] fusion vs. fission
I was trying to describe to my buddy the difference between fusion and fission and my explanation got a jumbled up, which made me realize how I myself don't really understand the difference. My understanding is...
fission - two or more particles combines...
Is it a rumor or is the government really devolping a fusion rocket. From what I've heard it's so strong it could get us to Mars in as quick as 8 ays. Not lieing 8 days. If you wondering about the acceleration and deccearation it supposedly would have 1.5 time the force of gravity. So you could...
Hello.
Often high temperature data are not available.
I am missing the melting heat of many coumpounds.
However, rather precise binary phase diagrams are available.
(my examples deal with silicates, say CaO-SiO2 for example, http://www.npl.co.uk/mtdata/demo/dgox1.html)
I would like to...
I asked one of the professors in the nuclear engineering department recently how inertial fusion could be a viable energy source if so little matter was fused. He told me that I would be suprised and said that I should do the calculation myself. I found the volume of the pellet, but now I have...
This is a pretty interesting theory on the evolution of stars and planetary systems. If you have the bandwidth, watch the movie linked in the paper. Has anybody seen this movie before, and are there alternate interpretations?
http://xxx.lanl.gov/ftp/astro-ph/papers/0511/0511379.pdf
I recently came upon a reference to http://www.focusfusion.org, which led me to discover http://www.prometheus2.net and http://www.electronpowersystems.com. What these companies have in common is they propose to generate power using "clean" proton-boron fusion in a pulsed reactor. By pulsed, I...
I'm reading up on star formation and from what I've understood so far, is that protogalactic clouds with density fluctuations cool and then fragment after which, they fragment again into subfragments. Now do the density in these individual subfragments increase the temperature enough to start...
Hi. On a general discussion forum, we were debating wether gold could be obtained from iron; I argued that this is possible, since we are at the moment recreating, in accelerators, even harsher conditions that those necessary for the creation of gold (i.e. those of a supernova core collapse). A...
If we made a custom levitating coil like this:
http://www.geocities.com/Area51/Shire/3075/globe.html
so that we could suspend a small Iron ball in the levitation coil.
Next
If we added two small but powerful electromagnets to each opposite equatorial side of the Iron ball so we could play...
In the 1997 5th edition of the Halliday Resnick and Walker fund of Physics this question is asked about colliding two beams of deuterons directly toward each other as well as perhaps colliding deuterons with a steel target. p1116.
Why is this method not presently used.
Doesn't the ITER do...
a fellow physics major was explaining to me that the latest technique in fusion has to do with creating tritium rings and using them to create another ring, using that ring to create yet a third ring.
I'm only second year, so nuclear/particle physics are a bit over my head at this point. I'm...
Having been an avid movie watcher when I was younger, I've developed a sort of assumption that new power sources aren't very welcome in a country driven by oil economics.
I understand a lot of the answers will be speculation, but I'd like to hear some opinions.
Is it true that fusion is...
This is my first post here, so I'm not entirely sure whether or not this topic warrants a new thread. I've just had a simple idea that I'd like to get some feedback on, from people who have a little more experience in nuclear chemistry than I do.
I was wondering if it would be possible to...
http://news.bbc.co.uk/2/hi/science/nature/4629239.stm
What is all this nonsense about what 'we' are going to do about new energy sources? What is the most that 'we' are ever going to do--vote for a new 'Energy Czar' to head-up our worldwide Centrally Planned Economy, and then sit back while...
A 58.0 kg ice-skater moving at 6.25 m/s glides to a stop. Assuming the ice is at 0°C and that 53.5 percent of the heat generated by friction is absorbed by the ice, how much ice melts?
Should I first calculate the work? I know I need to use Delta U= Q-W...but what is Delta U in this case?
This may seem like a crazy or stupid question. Maybe both.
What if there was a way to generate fusion using an element like Hydrogen, and then, miraculously, discover a way to generate fission out of the end result (in this case Hellium)? Could the constant fusion-fission between Hydrogen...
I have been reading about fusors. The articles usually refer to aneutronic reactions as though they are fusion. But are they really? For example, the pB11 reaction yields He, but this is some sort of fission isn't it? I.e. we start of with a heavier isotope and produce lighter ones through...
Hi I was reading an article in the New Scientist, about how fusion can be created in a device no bigger than a coffee cup.
It said that an electrically polarised piece of deuterium doped lithium tantilate (don't know if this is the right spelling) placed in a strong electomagnetic field...
All right, you're going to have to really humor me here.
As far as I know, the only kind of 'cold' fusion that has ever been demonstrated to work is muon-catalyzed. The reason it isn't viable is that is takes so much energy in the first place to create muons and they have a very short...
http://physicsweb.org/articles/news/9/7/8/1
Strangely enough, while it looks similar, the experiment is actually different than the earlier Taleyarkhan experiment. Other than that, it is still equally controversial.
Stay tune for more development in this saga...
Zz.
Question about fusion...
What are the problems for development, continuouly power production and economical, in a nuclear fusion reactor and nuclear fusion power plant ?
PLEASE INFORM ME ABOUT THE CONTROLLED FUSION REACTOR.
Is possible the continuos use the fusor and plasma focus, using fuel : pB11 or D-He3.
Please send me information.
Best Regards
French fusion reactor and some other skeptical stuff
http://www.sciencedaily.com/upi/index.php?feed=Science&article=UPI-1-20050627-10372700-bc-nukefusion.xml
Someone brought this up on a non-scientific site and said it would "provide 2x the worlds energy". Obvious BS so I am wondering if...
I was reading aboot sono-luminescence, and the researcher from llnl, that thought that he had (mistakenly) produced nuclear fusion. With all of the info available that I could find aboot sono-luminescence...it all seems to come down to 'how fascinating, but we don't much aboot it'. With that in...
ok my final exam for chem is tomorrow and i need help badly on this practice problem! here it is:
3. When 9.250 kJ of heat is added to 20.0 g of ice at 0.0 degrees Celcius, what is the final temperature of the water? The heat of fusion for water is 335 J/g.
I don't know how on Earth to...
Would common sense dictate that along with providing energy, that each fusion reactor would double as a Helium balloon factory, or would I have to take it upon myself to lobby for the creation of such a facility when the time comes?
I would assume that any scientist worth his weight in salt...
Hey,
I remember watching a program (Horizon - UK) on an indian scientist who claimed to have caused cold fusion in a lab.
The program tried to recreate it (the procedures were not actually the same - but some big name scientists advised them which equipment would be used), and failed.
I...
I'm sure most saw the article in today's NY Times on "table top fusion".
(For those who haven't...)
http://www.nytimes.com/aponline/science/AP-Tabletop-Fusion.html?hp&ex=1114660800&en=6ac101f390e18d4d&ei=5094&partner=homepage
And the article does mention that this experiment doesn't do...
http://news.yahoo.com/news?tmpl=story&ncid=753&e=1&u=/ap/20050427/ap_on_sc/tabletop_fusion
The article says that the results of this experiment will be published in Thursday's edition of Nature. I'm sure many of you have subscriptions. Would anybody care to recap?
Which graduate field would be best if you want to help out in determining a way to harness fusion power at a net result and such? I was told plasma physics would be a good field if i want to go into that sort of research.
In this post on the blog of Harvard string theorist Lubos Motl, he writes:
Is it true that the power generated from fusion has increased by 14 orders of magnitude since the seventies, and that they're only a few orders of magnitude away from the goal? If so, does his last sentence suggest there...
If this is probable:http://news.bbc.co.uk/1/hi/sci/tech/4270297.stm
then 'Stars in a Jar' would be the ultimate weapon, clean thorough and totally effective.
Lets say the evidence existed from the LAN 'newmexico' database, and this mysteriously vanished along with other relevant papers...
Some principal nuclear fusion reactions which have been considered are:
1) D + T -> n + 4He
2) D + 3He -> H + 4He
3) D + D -> H + T / 3He + n
4) T + T -> 4He + 2n
5) T + 3He -> (various products)
6) H + 11B -> 3 (4He)
from G. H. Miley, H. Towner and N. Ivich, U. of...
I Have A Question about FUSION! Please Help!
I Have A Question about FUSION! Please Help!
the reaction of H and F produces about 500 kj/mol of energy:
how much energy is produced by the reaction of 2.0kg of H with 38 kg of F to produce 2 kmol of HF?
i know the answer is 5.0x 10 to...
I Have A Question about FUSION! Please Help!
I Have A Question about FUSION! Please Help!
--------------------------------------------------------------------------------
the reaction of H and F produces about 500 kj/mol of energy:
how much energy is produced by the reaction of 2.0kg...
Calculate the energy release for the complete fusion of one mole of deuterium
H + H = He + energy
i can't do the signs for mass number etc. it quotes the Avogadro constant so that's a clue but help!
http://billnye.ytmnd.com