Enthalpy

If the graphene sheet can be laid on zinc, then H+ going through graphene will release H upon reaction with Zn, and this H will be prevented from grouping to H2, hence stay available for other uses. That would be plausible to me. 190nm is just fine. Among the recent excimer lamps, you have: Ar2 (126 nm), Kr2 (146 nm), Xe2 (efficient 172 nm), KrCl (222 nm) and many more. List there http://old.iupac.org/goldbook/ET07372.pdf Providers: Heraeus, Ushio, Yuasa and more. Affordable, depending on your criteria. Excimer lamps are still a bit new, but with >10% efficiency, multi-kW power, and wavelengths where needed, I suppose they will open fully new paths to chemistry. Up to now, Hg lamps at 254nm needed indirect and inefficient methods like sensitizers. The new sources can excite one particular bond, hence be efficient and selective. Time to make PhD on the subject.

The question of biofuel versus food versus nature isn't obvious. When palm trees replace forest trees in Indonesia, the operation releases no net dioxide, competes with no food production, but takes the habitat for wild life. Brazil (~25 hab/km2) has enough room for both food and biofuel production, so deciders there tell "poverty makes people hungry, not the lack of land". But if growing biofuels around Paris, it does replace food production; the French won't starve from that, but overseas buyers may, as the EU exports less. I'd like to emphasize that biofuels are so heavily targeted by the petrol lobby (and the agriculture lobby, and the tax lobby = the politicians) that most "information" is crap, to a point that it's difficult to make a sensible opinion. Recently I read nonsense like "palm oil diester from Indonesia releases dioxide from cutting the forest and competes with food, so prefer the properly labelled one produced around Paris". Worryingly, some readers are going to believe that.

OK, claiming a known mass for quarks, and attributing it to codata was the bit in excess for me. There is no science in this operation. I give up. Fare well.

Yes. The frame would have to be fine-meshed enough so the current in and out jumps to the mesh, but the conductors must be thick enough. A good earth is difficult to achieve. It demands wet soil, and normally has wires spreading from the rod. Not easy with a mobile home... With an imperfect earth, I'd prefer a good Faraday cage, especially at the bottom of the mobile home.

I don't really grasp what you mean by "between orbitals", since they overlap so much. And as the electron location is centered on the nucleus, it doesn't change its position when it is an orbital or an other - only its shape and size. I don't understand "we don't observe the electron between orbitals". A transition is a weighed sum of both orbitals; it is as much or little observable as the initial or final orbital. The only difference of the wavefunction during the transition is that it is not stationary. What shall mean: electrons crossing quickly between orbitals? Some transitions take millions of years to proceeed. ----- It might possibly be that you imagine a point electron on an orbital. This would mislead you. An electron is a wave (though this wave has quantized properties); trapped around a nucleus, the electron in a stationary state is an orbital.

Is there still any maintained Java interpreter?

It's more probably the cable that catches the radio waves, though a pick-up is possible. The connected preamplifier is sensitive to the voltage induced in the cable. It does happen (and quite naturally...) when circuitry isn't designed well enough. A true antenna, for instance an authentic ferrite rod for radiocom, would be better than the guitar pick-up. If using a headphone, two electrodes in a fruit would suffice; it's a matter of proper design.

In the pre-chamber of a staged combustion engine, the propellant ratio is extremely de-tuned so the gas temperature fits the turbine. This makes the flame difficult to start, keep and re-start. The necessary oxygen amount at once would quench the flame, so instead, a small flow of oxygen first burns the fuel in a balanced, hot, slower flame; then the big flow is injected to obtain much lukewarm gas - there the combustion stops. Cyclopropane and methane (hi there), and all dense fuels, have the same difficulty as kerosene; only hydrogen is easier. This applies also to a fuel-rich pre-chamber where possible - so the sketch can generalize to "minor propellant" and "major propellant". The Rd-170 engine family brings the kerosene and both oxygen flows at each injector individually; due to the dilution and the gas speed after the final injection, the flame can't spread from an injector to an other. As Energomash states, "each injector is a combustion chamber". Some trimethylgallium and trimethylaluminium, hypergolic with oxygen, flow before kerosene to light it. This design has advantages like easily cooled parts, but trimethylgallium is dangerous and the engine would be difficult to restart in flight. I suggest instead to let the hot flames communicate between the injectors, upstream of the main oxygen flow. One or few igniters then suffice, avoiding the pyrophoric propellant. One example is a Diesel glow plug, optionally adapted to rocket engines as I describe there http://forum.nasaspaceflight.com/index.php?topic=27308.0 on 01/13/2012 it likes oxygen-rich flames, has a significant resistance to heat, and is insensitive to soot. The sketched whirl injectors aren't necessarily the best choice. Parts of the pre-chamber must be cooled like a main chamber. And because the small flow flame has more room available, the pre-chamber might be downsized. Marc Schaefer, aka Enthalpy

What do you call Para 31? Does Codata give a mass difference between up and down quark, despite both are unknown (provided "mass" means something for them)? Or what do you call said "mass difference"?

How intimate would be enough? Single atoms of zinc? Nanodots? Or the graphene sheet just sits on zinc, and H+ flow through it? Nice, since graphene would prevent hydrogen atoms to first move at the zinc surface. CO bonds are a more likely candidate to catch hydrogen. What you might give a try: a hydrogen plasma. Low pressure, very low voltage - and low intensity and duration, because graphene contains few atoms... An other direction: excite the pi bonds with light, within gaseous hydrogen. Widely delocalized pi are passive, but excitation gives them punch. Despite they absorb long wavelengths also, I'd go to hard UV (excimer lamps and the like, they're spreading presently) to shake the delocalized electrons locally enough. Fun. So the "nascent hydrogen" was just an electron transfer... Not a good explanation for graphene, since H+ is said not to operate, but H yes.

Brazilians already use ethanol on a daily basis. More precisely, a mixture with gasoline. It works nicely, especially as it pollutes less than pure gasoline: in Rio you can have 5 lanes full of cars waiting at a traffic light, and you cross in acceptable air. I can't tell if the crop for ethanol needs artificial irrigation in Brazil. But we can still use fresh water at one place when it's missing at an other, because water is too difficult to transport.

Starting fusion is rather easy. Fusors do it. Some experiments with exploding conductors around liquid deuterium do it with modest energy and size. I'm absolutely confident that the Z-machine does it routinely when configured to do so. The difficulty is to extract more useable energy from fusion than was invested to attain the conditions. This is difficult even with deuterium and tritium, the most easy candidates by far. The Z-machine is not officially meant for that purpose, but of course people play with this possibility. If some day fusion of nuclides without tritium (which is too scarce) becomes interesting, then possibly thanks to the Z-pinch, which achieves conditions sufficient to ignite exotic combinations, much more naturally than laser shots and tokamaks. Did you mean natural "lightning"? It's much weaker than the Z-machine.

From what I imagine to understand of the general-public-paper, the neutron star has a bigger proportion of its mass composed of the mutual attraction of its particles, and the white dwarves a smaller proportion for being less dense. Then, if the mutual attraction of the particles contributes even slightly more (or less) to the inertial mass than to the gravitational mass, the result cumulated over astronomical time must be observable - something like; one star ejected from the trio. Or, as the movement of neutron stars might be observable accurately, it might result in some kind of precession. Please take with caution.

At least from en.Wiki: "The most abundant isotope, 40Ca, is theoretically unstable on energetic grounds, but its decay has not been observed." So unless you have better sources than Wiki, I read it as "stable until observed to decay" rather than "it must decay, just wait a little". I usual wording: only one element is stable for a given atomic mass. For which I see in my usual http://www.webelements.com/ (choose an element there, click on Isotopes then) and checking at wiki's "isotopes of...": 64Ni and 64Zn (64Zn observationally stable, "believed to decay by double beta-plus" never observed) 58Fe and 58Ni (58Ni observationally stable, "believed to decay by double beta-plus" never observed) 84Kr and 84Sr (84Sr observationally stable, "believed to decay by double beta-plus" never observed) 86Kr and 86Sr (86Kr observationally stable, "believed to decay by double beta-minus" never observed) Until one or several of these decays are observed, I'd feel prudent to consider that the nuclides are stable.

Err, expect no acrylic on a telescope mirror - their metal is on the front side. Recent ceramics for astronomy mirrors aren't even transparent.

If it's not for what many people think at, then maybe as a propellant for a rocket engine: http://www.scienceforums.net/topic/81051-staged-combustion-rocket-engines/ but since methylamine is a mass-produced commodity, I'd expect rocket builders to buy it.

Intuitively (so check other sources) I'd say: Since H+ arrive separated at the zinc surface, atomic H must result at the metal surface. I expect the H atoms to move along the metal surface until they meet an other H atom, then form a H2 molecule, and after some time leave the metal, for instance when enough H2 molecules have met to form a bubble, and the bubble is big enough.

en.wiki tells "is related to the Bose–Einstein condensation, but it is not identical" http://en.wikipedia.org/wiki/Superfluidity http://en.wikipedia.org/wiki/Superfluid_helium-4 For instance the narrow peak of heat capacity at a clear transition temperature tells something more happens than just a Bose-Einstein condensation.

Lightning protection doesn't have to be a complete Faraday cage. It's usually a few conductors: typically 2-3 masts, connected together through the tip of the roof, and to Earth through a single conductor. The conductors I see are like 6 to 8 mm in diameter. If no mast is possible, you won't know in advance where the bolt may strike, and then a metal sheet is better, BUT this sheet would need to evacuate the big current density from any point, hence be thick. A common rule is that a mast protects a cone of 2*45° under it, so it must be tall, or you need several ones. Antennas are bolt catchers, generally unwanted ones. Prefer antenna designs that are in short-circuit for DC. Beware the antenna cable will definitely carry the bolt inside unless you provide a path to Earth, be it the antenna cable itself (less than perfect) or a separate cable. The Earth contact must be excellent. This is difficult at a house, more so at a mobile home, impossible when moving. In a car, where this Earth contact is bad, the Faraday cage protects better.

With 40 nucleons, you have Ar and Ca, both stable. I find many curves interesting in your files, but am a bit mislead by your choice of words. "Nuclide" usually designates one couple of proton and neutron numbers, apparently it's their sum in your files. As well, an "Isotope" uses to designate variants of an element with a distinct number of neutrons. I also wish more detailed captions at the curves, for instance units, explanations of what the axes represent, where numbers start if it's not zero... Just as an exemple, page 5 of Isoanal1.pdf: Is it the density of the lone atom, the element in its standard form, the nucleus? I suppose the nucleus, but why a Rydberg constant then? What is the stable nuclide with 8 nucleons? Or did I misinterpret the curve on page 8 of Isoanal1.pdf? By the way, if someone can explain me why two alphas need an additional neutron to bind, but three and four don't, thanks in advance! I wouldn't like to appear too critic - your work is impressive, and is the kind of broad compilation needed to extract intelligible patterns. ---------- (Later post) The correlation with the crystal form is astounding. Did you check its statistical significance? Which crystal form did you choose for each element? Most have several ones, not mentioning the compounds of these elements. While we can influence the crystal form, this has no effect on the decay energy nor period. So would the correlation, if significant, indicate that the nucleons organise with caracteristic numbers (not periods neither) that, at least over some interval, resemble the electronic shells? ---------- You checked for periods in the curves. Older theories wanted to see so-called magic numbers; these worked a bit better than periods, though not satisfactorily, as for instance 56Co is unstable but 56Fe stable. Possibly an interesting extension would be to subtract the contribution of electronstatic repulsion from the mean nucleon mass. This would: - Show more clearly if there are patterns in the nucleon attraction versus their number - Tell if the protons spread uniformly in the nucleus, or group a little bit at the surface one difficulty being that big nuclei are not all spherical.

He-4 gets superfluid around 2K while He-3 needs some 1mK. This is a strong suggestion of boson versus fermion behaviour - the other difference being the magnetic moment of He-3. A BEC is suggested as the cause of superfluidity, yes.

Hello everybody! Staged combustion lets one propellant pass fully through a pre-chamber (or gas generator) at high pressure, adds a bit of the other propellant to burn it partially to a moderate temperature, and pass the big flow through the turbine. This gives more power to the pumps, and the higher pressure in the main chamber makes a more efficient engine. I've much simplified my obscure sketches here under; the reader may imagine in his clear mind: Each propellant passes first through a booster turbopump. A second impeller brings only the small fraction of auxiliary propellant to the pre-chamber pressure. This saves power, the gain is notable. A propellant flows through the cooling jacket. Preferably at nearly the chamber pressure. Staged combustion has been used on many hydrogen engines. As opposed, hydrocarbon fuels (including methane) would soot with so little oxygen, and oxygen consitutes most their propellant moles anyway, so the pre-chamber is oxygen-rich for hydrocarbons; the difficulty of hot oxygen has been addressed only by the Soviets and Russians up to now, resulting in the superior Rd-180 engine for instance. As an exception, methylamine CH5N would not soot with little oxygen. One might also try ethylene diamine dissolving much guanidine and maybe some methylamine; there are very few possibilities. Because its hot gas is lighter, and nitrogen adds moles, methylamine achieves almost the same main chamber pressure as oxygen with Rg-1, and this better fuel gain 5s specific impulse, with a fuel-rich pre-chamber. The comparison conditions are imperfect but fair: 700bar and 600°C=873K in the pre-chamber, 74%-70%-88% efficiency at the turbines-pumps-injectors, 1.25 mechanical power margin. Though, I doubt about Codata's Hf298Liq = -47.3kJ/mol. -------------------- The next step is a full-flow staged combustion. It was considered for hydrogen-oxygen, and I believe never built; methylamine enables it. Two pre-chambers burn separately all the oxygen and fuel at moderate temperature: more gas in the turbines raise the main chamber pressure to further gain 4s specific impulse. It takes two turbopumps, but the sealing joints are easier. The fuel turbine has some power left and can optionally help rotate the oxygen pump if coupling the shafts: This raises the main chamber pressure from 312 to 334 bar. It gains only 1s specific impulse. Integration and seal joints are more difficult. 5s or 9s improvements do bring an advantage, but I wouldn't go to methylamine: It's very volatile (bp -6°C), flammable, toxic and caustic as an amine. It decomposes irregularly at heat or banal catalysts, without oxygen, producing hot gas. This implies oxygen in the cooling jacket. It has already been done but not gladly. Oxygen-rich staged combustion was developed five decades ago. It must be feasible now with better alloys, ceramic coatings, despite computers. Fuel-rich methylamine isn't required for staged combustion. A molybdenum turbine brings about the same improvement. Light big nozzles of SiC or niobium, also. Replacing Rg-1 by methyl- or cyclopropyl- substituted azetidine, diazetidine, diaza-spiroheptane (choose for liquid range), as well. Oxygen in the cooling jacket enables other, more efficient fuels. Maybe a combination of nonvolatile amines can replace methylamine? Marc Schaefer, aka Enthalpy

Normal people use C++ only to interface with Windows, and program their application nearly in C. For that, you need to know very little of C++. Then, you can cheat an awful lot, and the complexity of C++ keeps manageable. If one really wants to know C++ completely, it's really big, and not so useful. The intermediate version, for someone who needs some features of C++, is to neglect learning the others, and keep a simple reference at hand for what he really needs. Similar to the operator precedence of C, for which programmers know it's in page 48 of Kernighan and Ritchie, you may know where the rules of name visibility are listed, or the precedence of homonym functions, or the type conversions.

The surface of a neutron star comprises protons, electrons and compounds. I imagine it just like a chemical equilibrium: deep enough, the pressure favours the denser form, that is neutrons. And the equilibrium means transformations in both directions, with pressure accelerating the transformation into neutrons.

Engineering is all about figures. Would you check the charge available from a bolt (or the energy, provided one can make the necessary voltage transformation and rectification) and tell us how much hydrogen is produced?