scholarly journals Metallic Hydrogen

2021 ◽  
Vol 6 (2) ◽  
Author(s):  
Isaac Silvera ◽  
Ranga Dias
Keyword(s):  
Alternative Fuels ◽  
Metallic State ◽  
Metallic Hydrogen ◽  
Holy Grail ◽  
The Earth ◽  
Diamond Anvils

For over eighty years, scientists have been trying to produce lab-made metallic hydrogen, the holy grail of alternative fuels. In that process, diamond anvils must withstand pressures greater than those at the center of the earth—no mean feat. Recent research may have finally achieved hydrogen’s metallic state. All that remains is for another lab to reproduce the results.

How to Tell the Left From the Right

1979 ◽  
Vol 9 (3) ◽  
pp. 387-412
Author(s):  
John McMurtry
Keyword(s):  
Holy Grail ◽  
Left Hand ◽  
The Earth ◽  
Thomas Malory ◽  
The Cross ◽  
The Right ◽  
Political Vocabulary ◽  
Ways Of Life

“If thou go on the left hand, thou shalt in this way be soon essayed.”Words on the Cross to Sir Galahad, The Holy Grail, by Thomas Malory, Chapter XIIWords on the Cross to Sir Galahad,The Holy Grail, by Thomas Malory, Chapter XIIThough left and right are fundamental terms of our social and political vocabulary, perhaps indeed the ultimate dividing concepts of ways of life on the earth today, their meaning seems to be as obscure as their application is ubiquitous.

scholarly journals Some properties of the metallic state I—Metallic hydrogen and its alloys

1937 ◽  
Vol 159 (897) ◽  
pp. 295-306 ◽  
Keyword(s):  
Low Temperature ◽  
High Temperatures ◽  
Low Temperatures ◽  
Simple Structure ◽  
Negative Ions ◽  
Energy Change ◽  
Metallic State ◽  
Metallic Hydrogen ◽  
Hydrogen Atoms ◽  
Energy Of Formation

An investigation of the properties of metallic hydrogen is of particular interest, on account of the simple structure of a metal composed of protons and electrons. A calculation of the energy change on forming a body centred lattice of metallic hydrogen from hydrogen atoms has recently been made by Wigner and Huntingdon (1935). They find that the energy of formation of metallic hydrogen from hydrogen atoms would be 10 kcal., and of metallic deuterium from deuterium atoms 11·6 kcal., but that metallic hydrogen (Graham’s hydrogenium) would only be stable relatively to covalent hydrogen at pressures not less than 2·5 × 10 5 atmospheres. Experiments on hydrogen at these pressures have not yet been realized. It is however possible to study the properties of metallic hydrogen in a number of alloys. At high temperatures, hydrogen dissolves to an appreci­able extent in a number of metals (Sieverts and Gotta 1928), but at low temperatures the only examples where hydrogen dissolves appreciably without forming covalent links (as GeH 4 ) or negative ions (as LiH) are the “metallic” hydrides of transitional elements such as palladium, tantalum, titanium, etc. The exceptional position of these low temperature alloys of metallic hydrogen is referred to again below. The evidence that hydrogen is in the metallic state has been reviewed (Ubbelohde 1931) and may be summarized by the statements that the hydrogen dissolves as atoms, and that at least a portion of these atoms is ionized to give electrons and protons.

scholarly journals Far-reaching governance of electrode potential: The case of priority in metal exploitation

2019 ◽  
Vol 84 (11) ◽  
pp. 1249-1259
Author(s):  
Svetomir Hadzi-Jordanov
Keyword(s):  
Electrode Potential ◽  
Raw Materials ◽  
Mineral Resources ◽  
Electrode Reaction ◽  
Metallic State ◽  
Technical Standard ◽  
Iron Aluminum ◽  
The Earth ◽  
Oxidation Reduction ◽  
Human Use

Is the priority applied during metals introduction in mankind?s service responsible for the forthcoming crisis in raw materials supply? Was the priority erroneous? To solve this dilemma, the relevant characteristics of GCIAL metals were compared, the acronym standing for gold, copper, iron, aluminum and lithium. These five metals were ranged according to: 1) the time of their incorporation in exploitation, 2) their abundance in the Earth?s crust, 3) reserves of mineral resources, 4) their stability and, partially, 5) the achieved level of mankind?s scientific highlights and technical expertise in that period. It was shown that the start of exploitation of the GCIAL metals does not correlate at all with their abundance, or their reserves in nature, but there is a straight correlation with their stability in the metallic state, as expressed by the corresponding values of the normal electrode potential. This is an expected behavior because the electrode potential is an alternative way of expressing the Gibbs energy change during the oxidation/reduction electrode reaction. Such a result also eliminates any doubt of error mentioned above. Thus, it is clear that the introduction of metals in human use was determined by their nature only and has nothing in common with insufficient abundance not only for the GCIAL metals, but probably for all other ?technical metals?, the main pillars of our technical standard.

scholarly journals Formation of iron hydride and iron carbide from hydrocarbon systems at ultra high thermobaric conditions

2019 ◽  
Vol 64 (9) ◽  
pp. 995-1002
Author(s):  
A. Yu. Serovaiskii ◽  
A. Yu. Kolesnikov ◽  
V. G. Kutcherov
Keyword(s):  
Upper Mantle ◽  
Laser Heating ◽  
Chemical Interaction ◽  
Iron Carbide ◽  
Iron Carbides ◽  
The Earth ◽  
Iron Hydride ◽  
Thermobaric Conditions ◽  
Diamond Anvils ◽  
Iron Bearing

The chemical interaction of hydrocarbon systems and iron-bearing minerals was investigated under extreme thermobaric conditions, corresponding to the Earth upper mantle. As a result of the reaction, the formation of iron carbide and iron hydride was detected. The experiments were carried out in diamond anvils cells with laser heating. Natural petroleum from the Korchaginskoe deposit and a synthetic mixture of paraffin hydrocarbons were used as hydrocarbon systems, and pyroxene-like glass and ferropericlase (57Fe enriched) as iron bearing minerals. The experiments were carried out in the pressure range of 26–95 kbar and temperature range of 1000–1500°C (±100°C). As a result of the experiments, the formation of iron hydride was detected at pressure of 26–69 kbar (corresponds to a depth of 100–200 km), and a mixture of iron carbide and iron hydride at pressure of 75–95 kbar (corresponds to a depth of 210–290 km). The formation of hydrides and iron carbides as a results of the interaction of hydrocarbon systems with iron-bearing minerals may indicate the possible existence of these compounds in the upper mantle.

scholarly journals Metal Carbides & hydrides : Structure and Superconductivity under high pressure

2014 ◽  
Vol 70 (a1) ◽  
pp. C1535-C1535
Author(s):  
Rajeev Ahuja
Keyword(s):  
High Pressure ◽  
Critical Temperature ◽  
Experimental Studies ◽  
Phase Iii ◽  
Metallic State ◽  
Metallic Hydrogen ◽  
Experimental Realization ◽  
Graphite Sheet ◽  
Research Activities ◽  
Critical Temperature Tc

The long-standing prediction that hydrogen can assume a metallic state under high pressure, combined with arguments put forward more recently that this state might even be superconducting up to high temperatures, continues to spur tremendous research activities toward the experimental realization of metallic hydrogen. These efforts have however so far been impeded by the enormous challenges associated with the exceedingly large required pressure. Hydrogen-dense materials allow for the rather exciting opportunity to carry out a proxy study of metallic hydrogen and associated high-temperature superconductivity at pressures within the reach of current techniques. In the present work, we have used first-principles methods in an attempt to predict the superconducting critical temperature (Tc ) as a function of pressure (P) for metal-hydride systems. By comparing the obtained results, we are able to point out a general trend in the Tc-dependence on P. These gained insights presented here are likely to stimulate further theoretical & experimental studies of metallic phases of hydrogen-dense materials. CaC6 is superconducting with a critical temperature Tc of 11.5 K. Under pressure first Tc increases and then suppresses and the superconductivity of this compound is eventually destroyed at about 18 GPa. Here, we report a theoretical finding of the re-emergence of superconductivity in heavily compressed CaC6. The predicted phase III with carbon nanofoam is found to be stable at wide pressure range with a Tc up to 14.7 K at 78 GPa. For CaC2, we found that under compression, dumbbell carbon in CaC2 can be polymerized firstly into one-dimensional chain and then into ribbon and further into two-dimensional graphite sheet at higher pressure. Our results show that calcium can not only stabilize carbon sp2 hybridization at larger range of pressure but also contribute in superconducting behavior, which would further ignite experimental and theoretical interest.

scholarly journals Some properties of the metallic state II—Metallic hydrogen and deuterium

1937 ◽  
Vol 159 (897) ◽  
pp. 306-313 ◽  
Keyword(s):  
Molecular Hydrogen ◽  
Zero Point ◽  
Heat Of Formation ◽  
Metallic State ◽  
Metallic Hydrogen ◽  
Heat Of Solution ◽  
Small Energy ◽  
Point Energy ◽  
The Difference ◽  
Chemical Linkage

The heat of formation of 1 g. atom of metal from the atoms has been calcu­lated to differ by about 1·6 kcal. for hydrogen and deuterium (Wigner and Huntingdon 1935). Allowing for the difference in the zero point energies of molecular hydrogen and deuterium (1·8 kcal. /mol. according to Rideal and Melville (1935)), the heat of formation of the metal from molecular hydrogen is smaller by 0·7 kcal./g. atom than from molecular deuterium. The difference in zero point energy between H and D in the α -phase is 0·5 kcal. /g. atom (Rideal and Melville). No data are available for the β -phase. This difference is about 6 % of the heat of solution in forming the β -phase, and since the expansion of the palladium lattice is sensitive to small energy changes (cf. Part I), an appreciable difference in expansions may be expected in the two alloys (cf. the discussion of other types of chemical linkage, Ubbelohde (1936). Measurements of the lattice expansion, and change of resistance on alloying with the two metals were undertaken to test this.

The motion of a lunar orbiter

1966 ◽  
Vol 25 ◽  
pp. 373
Author(s):  
Y. Kozai
Keyword(s):  
Degrees Of Freedom ◽  
Dimensional Space ◽  
Artificial Satellite ◽  
Equations Of Motion ◽  
Triaxial Ellipsoid ◽  
The Moon ◽  
Secular Motion ◽  
The Earth ◽  
Close Satellite ◽  
The Mean

The motion of an artificial satellite around the Moon is much more complicated than that around the Earth, since the shape of the Moon is a triaxial ellipsoid and the effect of the Earth on the motion is very important even for a very close satellite.The differential equations of motion of the satellite are written in canonical form of three degrees of freedom with time depending Hamiltonian. By eliminating short-periodic terms depending on the mean longitude of the satellite and by assuming that the Earth is moving on the lunar equator, however, the equations are reduced to those of two degrees of freedom with an energy integral.Since the mean motion of the Earth around the Moon is more rapid than the secular motion of the argument of pericentre of the satellite by a factor of one order, the terms depending on the longitude of the Earth can be eliminated, and the degree of freedom is reduced to one.Then the motion can be discussed by drawing equi-energy curves in two-dimensional space. According to these figures satellites with high inclination have large possibilities of falling down to the lunar surface even if the initial eccentricities are very small.The principal properties of the motion are not changed even if plausible values ofJ3andJ4of the Moon are included.This paper has been published in Publ. astr. Soc.Japan15, 301, 1963.

Formation of Lunar Craters and Bright Rays as a Result of Meteorite Impacts

1962 ◽  
Vol 14 ◽  
pp. 415-418
Author(s):  
K. P. Stanyukovich ◽  
V. A. Bronshten
Keyword(s):  
Explosive Charge ◽  
The Moon ◽  
Meteorite Impacts ◽  
The Earth ◽  
Lunar Craters ◽  
The Impact

The phenomena accompanying the impact of large meteorites on the surface of the Moon or of the Earth can be examined on the basis of the theory of explosive phenomena if we assume that, instead of an exploding meteorite moving inside the rock, we have an explosive charge (equivalent in energy), situated at a certain distance under the surface.

The Origin of the Moon

1962 ◽  
Vol 14 ◽  
pp. 149-155 ◽  
Author(s):  
E. L. Ruskol
Keyword(s):  
Chemical Composition ◽  
Solar System ◽  
The Moon ◽  
The Earth ◽  
The Difference ◽  
Origin Of The Moon

The difference between average densities of the Moon and Earth was interpreted in the preceding report by Professor H. Urey as indicating a difference in their chemical composition. Therefore, Urey assumes the Moon's formation to have taken place far away from the Earth, under conditions differing substantially from the conditions of Earth's formation. In such a case, the Earth should have captured the Moon. As is admitted by Professor Urey himself, such a capture is a very improbable event. In addition, an assumption that the “lunar” dimensions were representative of protoplanetary bodies in the entire solar system encounters great difficulties.

The Origin of the Moon and its Relationship to the Origin of the Solar System

1962 ◽  
Vol 14 ◽  
pp. 133-148 ◽  
Author(s):  
Harold C. Urey
Keyword(s):  
Solar System ◽  
The Moon ◽  
The Past ◽  
The Earth ◽  
Short Period ◽  
Origin Of The Moon

During the last 10 years, the writer has presented evidence indicating that the Moon was captured by the Earth and that the large collisions with its surface occurred within a surprisingly short period of time. These observations have been a continuous preoccupation during the past years and some explanation that seemed physically possible and reasonably probable has been sought.

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