Determination of Clay Bound Water in Shales from NMR Signals: The Fractal Theory

Use of the calorimetric and dilatometric methods for determination of ice in frozen tissues is criticized, and a method based on terminal melting points determined after various degrees of drying is proposed. The theoretical background of such a method lends support to it, and experimental work with gelatin is especially convincing. Use of the dehydration – melting point method on blood of Loxostege sticticalis gave results conforming in general to those obtained by other workers with calorimetric and dilatometric techniques, and also to those obtained with salt solutions. The amount of water that is bound is shown to be very low, as in mammalian, frog, and fish muscle. The possible influence of bound water in insect cold-hardiness is discussed and the conclusion is reached that it has little if any protective effect.

Download Full-text

Spin-echo methods for the determination of 31P transverse relaxation times of the ATP NMR signals in vivo

Magnetic Resonance Imaging ◽

10.1016/0730-725x(94)92359-0 ◽

1994 ◽

Vol 12 (1) ◽

pp. 121-129 ◽

Cited By ~ 9

Author(s):

Klaus Straubinger ◽

Wulf-Ingo Jung ◽

Michael Bunse ◽

Otto Lutz ◽

Klaus Küper ◽

...

Keyword(s):

Spin Echo ◽

Relaxation Times ◽

Transverse Relaxation ◽

Nmr Signals

Download Full-text

Zusammensetzung von Rohsulfan, Nachweis der Sulfane H2S9 bis H2S35 Composition of Crude Sulfane Oil, Identification of the Sulfanes H2S9 to H2S35

Zeitschrift für Naturforschung B ◽

10.1515/znb-1985-0220 ◽

1985 ◽

Vol 40 (2) ◽

pp. 263-272 ◽

Cited By ~ 21

Author(s):

Josef Hahn

Keyword(s):

Narrow Range ◽

Benzene Solution ◽

Chemical Shifts ◽

Upfield Shift ◽

Downfield Shift ◽

H Nmr ◽

Intramolecular Hydrogen ◽

Hydrogen Bondings ◽

Nmr Signals

In benzene solution the position of the 1H NMR signals of sulfanes, H2Sn, strongly depends on the sulfur chain length and on the sulfane concentration. Under proper conditions all sulfanes in a mixture are characterized by well-resolved NMR signals showing a downfield shift with increasing length of the sulfur chain. The shift differences between the higher homologues ( n > 8 ) remain nearly constant, thus allowing the assignment of the signals up to H2S35 and the determination of the complete sulfane distribution in crude oils. In sulfane mixtures without solvent as well as in CS2 and CCl4 solutions, however, H2S8 shows the largest downfield shift. The signals of the higher sulfanes overlap in a narrow range at slightly higher field and cannot be characterized except for the CCl4 solution where an assignment up to H2S11 is possible. The chemical shifts are interpreted in terms of inter- and intramolecular hydrogen bondings. The upfield shift caused by benzene is attributed to the formation of H2Sn · benzene complexes.

Download Full-text