A high pressure NMR study of solid methane

Nijman, A.J.; Trappeniers, N.J.

doi:10.1016/0378-4363(78)90087-6

Cited by 13 publications

(9 citation statements)

References 26 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…These perhaps represent the inner accretionary bank of Bluck (I 971) which grades up into massive mudstones of the flood plain. Similar deposits have been reported from the Eocene Castisent Formation of the south Pyrenean Basin (Nijman & Puigdefabregas, 1978). Where thick developments of accretionary bank/levee deposits are present (e.g.…”

Section: Point Bar Modelsupporting

confidence: 81%

“…The Sudmoor Point Sandstone has many features in common with the Castisent Formation described by Nijman & Puigdefabregas (1978). In particular, both sequences are interpreted as having accretionary bank, transverse bar and late stage run-off features, whilst differentiation of facies along the point bars may also be a common characteristic.…”

Section: Point Bar Modelmentioning

confidence: 92%

“…Allen, 1970a;Cant & Walker, 1976). Little is also known about detailed lateral facies changes, although it is becoming increasingly clear that complex lateral facies relationships occur in modern (Bluck, 1971;Jackson, 1976b;Cant, 1978) and ancient (Nami, 1976;Nijman & Puigdefabregas, 1978)…”

Section: Introductionmentioning

confidence: 99%

See 2 more Smart Citations

A meander‐belt sandstone of the Lower Cretaceous of Southern England

Stewart

1981

Sedimentology

View full text Add to dashboard Cite

A B S T R A C TThe meander-belt deposit comprises a sandstone resting on an erosion surface and bounded above and below by massive varicoloured mudstones with rootlet traces. The sandstone unit is composed of six bodies separated from one another, horizontally, by erosion surfaces; together the bodies form a single multilateral sand body. Internally each body is composed of lateral accretion units inclined at up to 6" from the horizontal. Vertical sequences of facies show significant variations but the grain size generally fines upwards. The principal lithofacies within the sandstones are, in common ascending order, intraformational conglomerate, large-scale cross-bedded, horizontal bedded and small-scale cross-laminated sandstone, and alternate sandstones and mudstones. Current directions are normal to the true slope of accretion surfaces and show insignificant scatter within individual bodies but are very diverse overall. Five of the sand bodies are believed to represent individual point bars, and one body an abandoned channel. Together they comprise the meander belt. The river was subject to very variable discharges and carried high suspended loads. Analysis of vertical profiles indicates that grain size segregation along the length of the point bars caused differentiation of the bars into coarsegrained heads and sandy tails.

show abstract

Section: Point Bar Modelsupporting

confidence: 81%

Section: Point Bar Modelmentioning

confidence: 92%

See 1 more Smart Citation

A meander‐belt sandstone of the Lower Cretaceous of Southern England

Stewart

1981

Sedimentology

View full text Add to dashboard Cite

show abstract

“…Study of these processes has been carried out either directly using structural methods [6,7] and the method of nuclear magnetic resonance [8][9][10], or indirectly, by examining the impact of conversion processes on the macroscopic characteristics of solid methane. This most clearly affects the vibrational spectra of methane in the range of translational and librational vibrations [11,12], as well as the thermophysical properties of methane, such as heat capacity [13,14], thermal conductivity [15], and density [16,17].…”

Section: Introductionmentioning

confidence: 99%

Refractive indices and density of cryovacuum-deposited thin films of methane in the vicinity of the α-β-transition temperature

Drobyshev¹,

Aldiyarov²,

Sokolov³

et al. 2017

Low Temperature Physics

View full text Add to dashboard Cite

Experimental studies of the effect of methane condensation temperature on the value of the refractive index and density of the resulting thin films are reported. The main unit of the installation is a high-vacuum chamber, which routinely operates at 10 -8 -10 -6 Torr. Measurements using a two-beam He-Ne laser interferometer in the vicinity of the methane phase transition temperature T = 20.4 K in the range of 14-32 K were carried out. It has been shown that in the vicinity of T = 20 K the temperature dependence of the refractive index undergoes an abrupt decrease with decreasing temperature. It is assumed that this gap is the result of the phase transition from the orientational disordered phase (α-phase) to the partially ordered phase (β-phase) of solid methane. The calculations of the polarizability of the methane molecules in the solid phase at two values of the deposition temperature T = 16 K and T = 30 K were performed using the Lorentz-Lorenz equation.

show abstract

“…Among the many investigations in this field one might mention an early systematic T , measurement (I), information on tunnel splitting (2), structure determination of phase I1 (3), and a high pressure study of phase diagrams (4). A recent nmr study at very low temperatures revealed new aspects of the methane problem.…”

Section: Introductionmentioning

confidence: 99%

Temperature variation of nuclear magnetic resonance line shape in solid CHD₃

Okada¹,

Ozaki²,

Maki³

1988

Can. J. Chem.

View full text Add to dashboard Cite

676 (1988). Faisant I'hypothkse qu'il se produit une conversion conskcutive des modifications de spin, on a calculk la forme des raies en resonance magnktique nuclkaire du CHD3 a l'ktat solide. On peut utiliser une concentration variable des especes de divers spins nuclkaires pour ajuster la variation, en fonction de la tempkrature, des raies d'absorption en rksonance magnktique nuclkaire qui sont observkes 5 basses temperatures a l'aide d'une largeur de raie de Gauss simple.[Traduit par la revue] I. IntroductionThe observation of nuclear magnetic interactions has given valuable information on the structure and molecular motion in the solid methanes. Among the many investigations in this field one might mention an early systematic T , measurement (I), information on tunnel splitting (2), structure determination of phase I1 (3), and a high pressure study of phase diagrams (4). A recent nmr study at very low temperatures revealed new aspects of the methane problem. Precise measurements of nmr line shapes in solid deuterated methanes by Buchman et al. (5)(6)(7) show remarkable temperature variation of the line shapes, especially of CHD3. From their results these authors claim that there is no nuclear spin conversion in CHD3 at low temperatures. Although they obtained good results for the nrnr line shape, their analysis gave a poor fit to the heat capacity data (8) in spite of the employment of many adjustable parameters.In the present article we shall give an alternative and better explanation of the nmr data for solid CHD,. Our model of rotational tunneling in solid CHD3 is the same one already found by one of the present authors to give an excellent fit to the experimental data for the heat capacity of all the isotopic methanes (1 1). We shall show that the nrnr data can also be

show abstract

A high pressure NMR study of solid methane

Cited by 13 publications

References 26 publications

A meander‐belt sandstone of the Lower Cretaceous of Southern England

A meander‐belt sandstone of the Lower Cretaceous of Southern England

Refractive indices and density of cryovacuum-deposited thin films of methane in the vicinity of the α-β-transition temperature

Temperature variation of nuclear magnetic resonance line shape in solid CHD₃

Contact Info

Product

Resources

About

A high pressure NMR study of solid methane

Cited by 13 publications

References 26 publications

A meander‐belt sandstone of the Lower Cretaceous of Southern England

A meander‐belt sandstone of the Lower Cretaceous of Southern England

Refractive indices and density of cryovacuum-deposited thin films of methane in the vicinity of the α-β-transition temperature

Temperature variation of nuclear magnetic resonance line shape in solid CHD3

Contact Info

Product

Resources

About

Temperature variation of nuclear magnetic resonance line shape in solid CHD₃