Results 141 to 150 of about 736 (155)

Ortho-Parahydrogen Conversion Studies

1960
Quantity production of liquid parahydrogen has been accomplished at the NBS-AEC Cryogenic Engineering Laboratory through use of a chromic oxide catalyst placed in the liquid receiver at the bottom of the hydrogen liquefier. (See Figure 1.) About 175 pounds of a commercial 20 percent chromic oxide on alumina or 100 pounds of a 30–35 percent chromic ...
P. L. Barrick, D. H. Weitzel, T. W. Connolly   +2 more
openaire   +1 more source

The Parahydrogen Conversion on Metals

Bulletin des Sociétés Chimiques Belges, 1958
AbstractLa conversion à basse température de l'hydrogène sur l'or diamagnétique fournit, quoique dans une mesure moindre qu'avec l'aluminium paramagnétique, des indications sur les valences libres superficielles postulées dans des calculs sur les chaleurs de chimisorption.L'effet de la pression à 90° K et à 195° K montre que la conversion est d'ordre 0
A. Couper, D. D. Eley, M. J. Hulatt, D. R. Rossington   +3 more
openaire   +1 more source

Thermal conductivity of parahydrogen

Journal of Chemical & Engineering Data, 1984
Mesure experimentale de la conductivite thermique du parahydrogene pour 8 isothermes de 100 a 275 K avec intervalles de 25 K, des pressions jusqu'a 12 MPa et des densites de 0 a 12 mol ...
openaire   +1 more source

Diffusion of hydrogen fluoride in solid parahydrogen

The Journal of Chemical Physics, 2013
We studied diffusion of hydrogen fluoride (HF) in solid parahydrogen (pH2) around 4 K. Diffusion rates were determined from time dependence of FT-IR spectra of HF monomers. The absorption of HF monomers shows temporal decay due to dimerization reaction via diffusion.
Hiroki, Ooe, Yuki, Miyamoto, Susumu, Kuma, Kentarou, Kawaguchi, Kyo, Nakajima, Itsuo, Nakano, Noboru, Sasao, Jian, Tang, Takashi, Taniguchi, Motohiko, Yoshimura   +9 more
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Sensitivity Enhancement Utilizing Parahydrogen

2007
The sections in this article are 1 Introduction 2 Nuclear Spin States of H2 and D2 3 General Theory of the PASADENA Effect 4 PASADENA Effect in Weakly Coupled Spin Systems 5 Experimental PASADENA NMR Spectroscopy in Liquids 6 The ALTADENA Effect 7 Theory of Ortho/Para D2 Enhancement 8 PASADENA Effect at a Solid Surface
openaire   +1 more source

Parahydrogen Catalysis by Transition Metals

Nature, 1949
WE have made experiments to test the hypothesis put forward in a recent review article1 that the activation of hydrogen gas by the transition metals is connected with the presence of unpaired d-electrons or holes in the electronic d-band of the metal.
A. COUPER, D. D. ELEY
openaire   +1 more source

Parahydrogen conversion on X zeolites

Journal of Catalysis, 1973
Abstract Parahydrogen conversion catalysed by X zeolites containing Na + , H + , and rare earth ions has been investigated over the temperature range 77–610 K. At low temperatures, conversion proceeds by a physical mechanism in which the activity is determined by rare earth ions and paramagnetic impurities.
openaire   +1 more source

Parahydrogen induced polarization

Progress in Nuclear Magnetic Resonance Spectroscopy, 1997
Johannes Natterer, Joachim Bargon
openaire   +1 more source

parahydrogen, n.

2023
openaire   +1 more source

Frontispiece: StereoPHIP: Stereoselective Parahydrogen‐Induced Polarization

Angewandte Chemie International Edition, 2023
Mai T. Huynh, Emily Buchanan, Sara Chirayil, Adeniyi M. Adebesin, Zoltan Kovacs   +4 more
openaire   +1 more source