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Artigo Acesso aberto

W. C. Roberts-Austen,

... metallic or other impurity on a mass of metal is shown by a remarkable series of phenomena ... the appearance and the physical properties of a metal as to lead, in the absence of other ... elemental substance. The valuable mechanical properties conferred upon metals by associating them with small, but definite, amounts of other metals constitute the main reason why metals devoted to industrial use are seldom employed in ... quantity of a metalloid on a mass of metal is presented by the extraordinary change in the ...

Tópico(s): History and advancements in chemistry

1888 - Royal Society | Philosophical Transactions of the Royal Society of London (A )

Artigo

Shuh‐ichi Nishikawa, G. Asahara,

X-ray patterns of metals; (1) effect of rolling.---By passing a narrow beam of heterogeneous rays through a thin sheet of metal, a pattern may be photographically recorded which depends on the crystalline structure of the metal. The authors have used this phenomenon to study ... effect of rolling and subsequent annealing on various metals. (a) In the case of aluminum, cadmium, copper, ... of rolling but each characteristic of a particular metal. (b) Silver and tin gave similar ill-defined ... spot patterns characteristic of annealed samples. For these metals, then, the crystal growth which accompanies annealing takes ...

Tópico(s): Electron and X-Ray Spectroscopy Techniques

1920 - American Institute of Physics | Physical Review

Artigo Acesso aberto

Frank Horton,

... been done in connection with the bombardment of metal surfaces by slow cathode rays. The work of ... when such rays fall on a negatively charged metal surface, electrons leave the surface, and that the ... primary stream which have been reflected at the metal surface, the characteristic of these reflected rays being ... above 11 volts—is an ionisation at the metal surface, the material ionised being either the metal itself or gas attached to it. On this ... found to be the same for all the metal surfaces tested, and as it agreed with the ...

Tópico(s): Laser-induced spectroscopy and plasma

1920 - Royal Society | Proceedings of the Royal Society of London Series A Containing Papers of a Mathematical and Physical Character

Primary Document Acesso aberto

Dibarrart, Cen,

Caption title. "L'original de cette note est signé par le Cen. Dibarrart, l'un des Administrateurs des monnaies" Book.

0000 - Gale Group | The Making of Modern World

Artigo

C. V. Kent,

... determination of the two optical constants of molten metals, the index of refraction, $\ensuremath{\nu}$, and the ... from the reflection of polarized light at molten-metal surfaces, placed in an inactive atmosphere.The purpose ... light upon the behaviour of free electrons in metals.Method.---The constants, $\ensuremath{\nu}$ and $\ensuremath{\kappa}$, ... light reflected from the surface of the liquid metal at an angle of incidence $\ensuremath{\varphi}$. A ... of new design.A furnace for melting the metals is made up by winding a few yards ...

Tópico(s): Electron and X-Ray Spectroscopy Techniques

1919 - American Institute of Physics | Physical Review

Artigo

H. B. Peacock,

... filament, were measured. For films of the ferromagnetic metals, Fe, Co, Ni, the Hall coefficients were respectively ... 7.8 times the values for the corresponding metals in bulk, these factors being in the order ... the elements. For the paramagnetic, negative Hall effect metals, Pd and Pt, the Hall coefficients were 0. ... and 0.64 times the values for the metals in bulk. The increased Hall effect for the films of the ferromagnetic metals seems closely related to ferromagnetism, although Ni, the ... films to the specific resistances of the corresponding metals in bulk were found to be 3.1 ( ...

Tópico(s): Graphene research and applications

1926 - American Institute of Physics | Physical Review

Artigo Revisado por pares

Carl Wagner,

Under certain conditions, interaction between positively charged metal ions in an alloy may be considered to be of minor importance as compared to interaction between conduction electrons and metal ions. Then it follows that the activity of a solute metal 2 dissolved in metal 1 will be increased by a third component if metals 2 and 3 change the valence electron/atom ... same direction. Conversely, the activity of a solute metal 2 will be decreased by a third component if metals 2 and 3 change the valence electron/atom ...

Tópico(s): Thermodynamic and Structural Properties of

1951 - American Institute of Physics | The Journal of Chemical Physics

Primary Document -- Manuscript Acesso aberto

... Mascots Bull Dog - paper: 2 Mascots Bull Dog - metal. Ivory Cross. (formerly Soldiers' and Sailors' Dental Aid ...

1918 - Gale Group | ArchivesUnbound Women-War

Artigo

H. E. Farnsworth,

... The apparatus used to study the first six metals has been described in a previous ${\mathrm{paper}.}^{1}$ The last two metals and especially copper were studied with a modified ... depend on the previous heat treatment of the metals, but after heating the higher melting point metals red-hot for some time, limiting curves were obtained which are characteristic of the different metals. Each curve (except for Cu) rises sharply from ... large in comparison with those of the other metals, the ratio to primary current for Al reaching ...

Tópico(s): Ion-surface interactions and analysis

1925 - American Institute of Physics | Physical Review

Primary Document -- Manuscript Acesso aberto

Cloth badge and metal badge of Anglo Russian Hospital. Anglo Russian Hospital Lady Muriel Paget. Russia. RUSSIA 1/21. Book.

0000 - Gale Group | ArchivesUnbound Women-War

Artigo Revisado por pares

I‐Ming Feng,

A new theory of metal transfer and wear is suggested in this paper. The essence of the theory is as follows: Metal transfer and wear take place at points of ... these roughened interfaces is the primary cause of metal transfer and wear. Due to the mechanical interlocking ... at the original interface. A secondary cause of metal transfer is the adhesion or the diffusion process ... high spot to become a blob of transferred metal, the small piece of metal sheared from the high spot can leave as ... surface film. The effect of surface contamination on metal transfer, wear, and the shear component of friction ...

Tópico(s): Adhesion, Friction, and Surface Interactions

1952 - American Institute of Physics | Journal of Applied Physics

Artigo Revisado por pares

Luigi Gorini, Lucienne Audrain,

... des états de dénaturation de la protéine. Le métal peut agir directement (sérumalbumine traitée par la chaleur) ... cas (sérumalbumine non traitée par la chaleur), le métal joue un rôle indirect en agissant sur l' ... formes est attaquable par la trypsine, et le métal déplace l'équilibre vers l'autre forme pour ... The addition of ionised salts of certain bivalent metals such as calcium and manganese (and to a ... the states of denaturation of the protein. The metal can react directly (with serumalbumin warmed) to form ...

Tópico(s): Enzyme Catalysis and Immobilization

1952 - Elsevier BV | Biochimica et Biophysica Acta

Primary Document -- Manuscript Acesso aberto

Pamphlet Wartime Employment of Women in Metal trades. Research Report No. 8. National Industrial Conference Board. Wartime Employment. Employment. Jul. 1918. EMP. 76/1. Book.

1918 - Gale Group | ArchivesUnbound Women-War

Artigo Acesso aberto Revisado por pares

H. M. N. H. Irving, Charles Bell,

... widely used of all organic reagents for trace-metal determinations, its structure, and more particularly the structure of its metal complexes, are still in doubt. Several metals form two dithizone complexes, that with the lower proportion of metal being termed the keto-form, the metal-rich complex being known as the enol form. ... group of dithizone that is replaced by a metal (I, X = monovalent metal; IV, Y = divalent metal); whereas in the enol form the hydrogen atom ... the reagent (II, X = H) is replaced by metal as well (II, X = monovalent metal; V, Y = ...

Tópico(s): Chemical Reaction Mechanisms

1952 - Nature Portfolio | Nature