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Rembaum, A.

Publications and source records attributed to Rembaum, A..

At least 55 records · Page 3
All sourcesNASA NTRSDOE OSTI
NASA NTRS1972

Magnetic field effects on superconductivity in alkali metal intercalates of MoS2

The effects of a magnetic field on the superconducting transition in MoS2 intercalated with potassium and sodium were studied. It was found that the potassium intercalated MoS2 has better properties in a magnetic field. In zero magnetic field the transition to superconductivity begins near 6.4 K. Diagrams of the basic circuitry for superconducting transition studies, and charts showing critical magnetic field versus critical temperature for the intercalated MoS2 are included.

Woollam, J. A.↗
NASA NTRS1972

Superconductivity in the alkali metal intercalates of molybdenum disulphide

The complete series of alkali metals, lithium through cesium, have been intercalated into molybdenum disulphide, using both the liquid ammonia and vapor techniques. All the intercalates with the exception of lithium yielded full superconducting transitions with onset temperatures of 6 K for AxMoS2(Ax=K,Rb,Cs) and 4 K for BxMoS2(Bx=Li,Na). The superconducting transition for lithium was incomplete down to 1.5 K. Stoichiometries and unit cell parameters have been determined for the intercalation compounds. Both rhombohedral and hexagonal polymorphs of MoS2 have been intercalated and found to exhibit the same superconductivity behavior. The nature of the extraneous superconducting transition of some intercalated samples on exposure to air was elucidated.

Somoano, R. B.↗
NASA NTRS1972

Viscoelastic cationic polymers containing the urethane linkage

A method for the synthesis and manufacturing of elastomeric compositions and articles containing quaternary nitrogen centers and condensation residues along the polymeric backbone of the centers is presented. Linear and cross-linked straight chain and block polymers having a wide damping temperature range were synthesized. Formulae for the viscoelastic cationic polymers are presented.

Rembaum, A.↗
NASA NTRS1972

Pressure transducer

A pressure transducer is described in which the sensing element is a crystal of the monomeric charge transfer complex of pyrene and tetracyanoethylene.

Rembaum, A.↗
NASA NTRS1972

Superconductivity in intercalated molybdenum disulfide.

X-ray studies show the existence of two different types of expansions of the intercalated unit cell in both Na and K compounds. Two different phases are also indicated in the superconducting behavior of the K compound. All intercalated samples studied show a superconducting transition. K and Rb compounds become superconductors in the temperature range from 6.5 to 6.0 K. The Na compounds become superconductors at about 4.5 K. In all cases, the superconductivity disappears upon a short exposure of the sample to air. This phenomenon confirms that the superconductivity is due to the presence of the alkali metal.

Somoano, R.↗
NASA NTRS1971

Onset of superconductivity in sodium and potassium intercalated molybdenum disulphide

Molybdenum disulfide in the form of natural crystals or powder has been intercalated at -65 to -70 C with sodium and potassium using the liquid ammonia technique. All intercalated samples were found to show a superconducting transition. A plot of the percent of diamagnetic throw versus temperature indicates the possible existence of two phases in the potassium intercalated molybdenum disulfide. The onset of superconductivity in potassium and sodium intercalated molybdenite powder was found to be approximately 6.2 and approximately 4.5 K, respectively. The observed superconductivity is believed to be due to an increase in electron density as a result of intercalation.

Somoano, R. B.↗
NASA NTRS1970

Nuclear alkylated pyridine aldehyde polymers and conductive compositions thereof

A thermally stable, relatively conductive polymer was disclosed. The polymer was synthesized by condensing in the presence of catalyst a 2, 4, or 6 nuclear alklylated 2, 3, or 4 pyridine aldehyde or quaternary derivatives thereof to form a polymer. The pyridine groups were liked by olefinic groups between 2-4, 2-6, 2-3, 3-4, 3-6 or 4-6 positions. Conductive compositions were prepared by dissolving the quaternary polymer and an organic charge transfer complexing agent such as TCNQ in a mutual solvent such as methanol.

Rembaum, A.↗
NASA NTRS1969

Heparin insolubilized with crosslinking agent

New plastic compositions, involving the systhesis of a polymeric system containing heparin insolubilized with crosslinking agents, show appreciable promise in human body implant technology.

Rembaum, A.↗
NASA NTRS1969

Ionene polymers. III

Dicationic crosslinking agents isolation and characterization and formation of polymers with ionic crosslinks

Keyzer, H.↗
NASA NTRS1969

Polyelectrolyte complexes

Polyelectrolyte complexes formed from combined water soluble and negatively charged polyelectrolytes

Rembaum, A.↗
NASA NTRS1968

Preparation of alkali metal dispersions

A method is described for producing alkali metal dispersions of high purity. The dispersions are prepared by varying the equilibrium solubility of the alkali metal in a suitable organic solvent in the presence of aromatic hydrocarbons. The equilibrium variation is produced by temperature change. The size of the particles is controlled by controlling the rate of temperature change.

Rembaum, A.↗