Low Field Methods (GMR, Hall Probes, etc.)

In this introduction I wish to analyse the problems that we face when using n.m.r. to tackle biological states in vivo . I shall refer to high resolution n.m.r. only, since the second half of the Discussion is devoted to low field methods. When referring to in vivo systems I shall include isolated whole cell systems, excised whole organs, and whole body studies, but I shall not discuss extracted chemical solutions. Studies of extracted solutions proceed by conventional means. I shall use a range of observations for illustrative purposes; most of these observations refer to work in which I have played a part at Oxford. The people who have been concerned in initiating this work are Dr I. D. Campbell, Dr C. M. Dobson, Dr P. E. Wright, Dr B. Levine, Dr A. Daniels and Dr R. G. Ratcliffe. In this symposium Dr Campbell and Dr Dobson will report in detail on some of their independent work.

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Analysis of the ferromagnetic contribution to the susceptibility by low field and high field methods in sedimentary rocks of the Southern Pyrenees and Northern Ebro foreland basin (Spain)

Terra Nova ◽

10.1111/ter.12037 ◽

2013 ◽

Vol 25 (4) ◽

pp. 307-314 ◽

Cited By ~ 5

Author(s):

Óscar Pueyo Anchuela ◽

Antonio M. Casas-Sainz ◽

Emilio L. Pueyo ◽

Andrés Pocoví Juan ◽

Andrés Gil Imaz

Keyword(s):

High Field ◽

Sedimentary Rocks ◽

Foreland Basin ◽

Field Methods ◽

Low Field ◽

Ferromagnetic Contribution

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Near-field scanning optical microscopy

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100144644 ◽

1986 ◽

Vol 44 ◽

pp. 642-643

Author(s):

E. Betzig ◽

A. Harootunian ◽

M. Isaacson ◽

A. Lewis

Keyword(s):

Near Field ◽

Optical Microscope ◽

Visible Radiation ◽

Field Methods ◽

Optical Elements ◽

Optical Region ◽

Order Of Magnitude ◽

Nondestructive Imaging ◽

Scanning Optical Microscopy ◽

Near Field Scanning

In general, conventional methods of optical imaging are limited in spatial resolution by either the wavelength of the radiation used or by the aberrations of the optical elements. This is true whether one uses a scanning probe or a fixed beam method. The reason for the wavelength limit of resolution is due to the far field methods of producing or detecting the radiation. If one resorts to restricting our probes to the near field optical region, then the possibility exists of obtaining spatial resolutions more than an order of magnitude smaller than the optical wavelength of the radiation used. In this paper, we will describe the principles underlying such "near field" imaging and present some preliminary results from a near field scanning optical microscope (NS0M) that uses visible radiation and is capable of resolutions comparable to an SEM. The advantage of such a technique is the possibility of completely nondestructive imaging in air at spatial resolutions of about 50nm.

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