Long Period of Time Cooling Technique Using Liquid Nitrogen for HTS-SQUID System

An analytical discussion of that case of motion in the restricted problem, in which the mean motions of the infinitesimal, and smaller-massed, bodies about the larger one are nearly in the ratio of two small integers displays the existence of a series of periodic solutions which, for commensurabilities of the typep+ 1:p, includes solutions of Poincaré'sdeuxième sortewhen the commensurability is very close, and of thepremière sortewhen it is less close. A linear treatment of the long-period variations of the elements, valid for motions in which the elements remain close to a particular periodic solution of this type, shows the continuity of near-commensurable motion with other motion, and some of the properties of long-period librations of small amplitude.To extend the investigation to other types of motion near commensurability, numerical integrations of the equations for the long-period variations of the elements were carried out for the 2:1 interior case (of which the planet 108 “Hecuba” is an example) to survey those motions in which the eccentricity takes values less than 0·1. An investigation of the effect of the large amplitude perturbations near commensurability on a distribution of minor planets, which is originally uniform over mean motion, shows a “draining off” effect from the vicinity of exact commensurability of a magnitude large enough to account for the observed gap in the distribution at the 2:1 commensurability.

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Discussion following the presentation by F. Deubner

International Astronomical Union Colloquium ◽

10.1017/s0252921100053240 ◽

1977 ◽

Vol 36 ◽

pp. 69-74

Keyword(s):

List Type ◽

The Sun ◽

Type Number ◽

Harmonic Motion ◽

Locally Excited ◽

Long Period ◽

Coherent Wave ◽

Short Period ◽

Global Modes

The discussion was separated into 3 different topics according to the separation made by the reviewer between the different periods of waves observed in the sun :1) global modes (long period oscillations) with predominantly radial harmonic motion.2) modes with large coherent - wave systems but not necessarily global excitation (300 s oscillation).3) locally excited - short period waves.

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The growth of mica polytypes as studied by conventional and high-resolution TEM

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100074690 ◽

1983 ◽

Vol 41 ◽

pp. 174-177

Author(s):

A. Baronnet ◽

M. Amouric

Keyword(s):

Water Pressure ◽

Point Of View ◽

Temperature Fields ◽

Natural Occurrence ◽

Growth Mechanisms ◽

Long Period ◽

High Resolution Tem ◽

Layer Stacking ◽

Experimental Works ◽

Potential Use

The origin of mica polytypes has long been a challenging problem for crystal- lographers, mineralogists and petrologists. From the petrological point of view, interest in this field arose from the potential use of layer stacking data to furnish further informations about equilibrium and/or kinetic conditions prevailing during the crystallization of the widespread mica-bearing rocks. From the compilation of previous experimental works dealing with the occurrence domains of the various mica "polymorphs" (1Mr, 1M, 2M1, 2M2 and 3T) within water-pressure vs temperature fields, it became clear that most of these modifications should be considered as metastable for a fixed mica species. Furthermore, the natural occurrence of long-period (or complex) polytypes could not be accounted for by phase considerations. This highlighted the need of a more detailed kinetic approach of the problem and, in particular, of the role growth mechanisms of basal faces could play in this crystallographic phenomenon.

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Electron Probe Microanalysis of Frozen Hydrated Kidneys, Isolated Cells, and Cultured Cells

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100054595 ◽

1982 ◽

Vol 40 ◽

pp. 402-403 ◽

Cited By ~ 1

Author(s):

Claude Lechene

Keyword(s):

Liquid Nitrogen ◽

Electron Probe Microanalysis ◽

Electron Probe ◽

Cultured Cells ◽

Liquid Nitrogen Temperature ◽

Elemental Content ◽

Isolated Cells ◽

Renal Tubular Cells ◽

Diamond Saw ◽

Saw Blade

Electron probe microanalysis of frozen hydrated kidneysThe goal of the method is to measure on the same preparation the chemical elemental content of the renal luminal tubular fluid and of the surrounding renal tubular cells. The following method has been developed. Rat kidneys are quenched in solid nitrogen. They are trimmed under liquid nitrogen and mounted in a copper holder using a conductive medium. Under liquid nitrogen, a flat surface is exposed by sawing with a diamond saw blade at constant speed and constant pressure using a custom-built cryosaw. Transfer into the electron probe column (Cameca, MBX) is made using a simple transfer device maintaining the sample under liquid nitrogen in an interlock chamber mounted on the electron probe column. After the liquid nitrogen is evaporated by creating a vacuum, the sample is pushed into the special stage of the instrument. The sample is maintained at close to liquid nitrogen temperature by circulation of liquid nitrogen in the special stage.

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A Liquid Nitrogen Cooled Stage for STEM

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100052237 ◽

1974 ◽

Vol 32 ◽

pp. 444-445

Author(s):

Louis T. Germinario

Keyword(s):

Electron Microscope ◽

High Resolution ◽

Liquid Nitrogen ◽

Room Temperature ◽

Objective Lens ◽

Thermal Drift ◽

Specimen Holder ◽

Resolution Capability ◽

Focal Position

A liquid nitrogen stage has been developed for the JEOL JEM-100B electron microscope equipped with a scanning attachment. The design is a modification of the standard JEM-100B SEM specimen holder with specimen cooling to any temperatures In the range ~ 55°K to room temperature. Since the specimen plane is maintained at the ‘high resolution’ focal position of the objective lens and ‘bumping’ and thermal drift la minimized by supercooling the liquid nitrogen, the high resolution capability of the microscope is maintained (Fig.4).

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Field-Ion Microscopy of BCC Metals: A Study of Image Differences and Topographical Variations

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100071016 ◽

1973 ◽

Vol 31 ◽

pp. 114-115

Author(s):

O. T. Inal ◽

L. E. Murr

Keyword(s):

Liquid Nitrogen ◽

Liquid Nitrogen Temperature ◽

Surface Atom ◽

Image Brightness ◽

Field Ion Microscopy ◽

Topographic Features ◽

Bcc Metals ◽

Electron Orbital ◽

Ion Microscopy ◽

Field Ion Microscope

When sharp metal filaments of W, Fe, Nb or Ta are observed in the field-ion microscope (FIM), their appearance is differentiated primarily by variations in regional brightness. This regional brightness, particularly prominent at liquid nitrogen temperature has been attributed in the main to chemical specificity which manifests itself in a paricular array of surface-atom electron-orbital configurations.Recently, anomalous image brightness and streaks in both fcc and bee materials observed in the FIM have been shown to be the result of surface asperities and related topographic features which arise by the unsystematic etching of the emission-tip end forms.

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The Effects of Drying Techniques on Clay-Rich Soil Texture

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100052341 ◽

1974 ◽

Vol 32 ◽

pp. 466-467

Author(s):

T. G. Naymik

Keyword(s):

Critical Point ◽

Liquid Nitrogen ◽

Liquid Nitrogen Temperature ◽

Drying Methods ◽

Air Drying ◽

Freeze Dried ◽

Critical Point Drying ◽

Set Up ◽

The Relationship ◽

Quartz Grains

Three techniques were incorporated for drying clay-rich specimens: air-drying, freeze-drying and critical point drying. In air-drying, the specimens were set out for several days to dry or were placed in an oven (80°F) for several hours. The freeze-dried specimens were frozen by immersion in liquid nitrogen or in isopentane at near liquid nitrogen temperature and then were immediately placed in the freeze-dry vacuum chamber. The critical point specimens were molded in agar immediately after sampling. When the agar had set up the dehydration series, water-alcohol-amyl acetate-CO2 was carried out. The objectives were to compare the fabric plasmas (clays and precipitates), fabricskeletons (quartz grains) and the relationship between them for each drying technique. The three drying methods are not only applicable to the study of treated soils, but can be incorporated into all SEM clay soil studies.

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TEM Analysis of Long-Period Polytypes in SiC—S

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100093110 ◽

1976 ◽

Vol 34 ◽

pp. 630-631

Author(s):

S. Shinozaki ◽

J. W. Sprys

Keyword(s):

Electron Diffraction ◽

Isothermal Annealing ◽

Tem Analysis ◽

Long Period ◽

Transmission Electron ◽

Average Grain Size ◽

High Resolution Tem ◽

Structural Lattice ◽

The Stability ◽

Continuous Curves

In reaction sintered SiC (∽ 5um average grain size), about 15% of the grains were found to have long-period structures, which were identifiable by transmission electron microscopy (TEM). In order to investigate the stability of the long-period polytypes at high temperature, crystal structures as well as microstructural changes in the long-period polytypes were analyzed as a function of time in isothermal annealing.Each polytype was analyzed by two methods: (1) Electron diffraction, and (2) Electron micrograph analysis. Fig. 1 shows microdensitometer traces of ED patterns (continuous curves) and calculated intensities (vertical lines) along 10.l row for 6H and 84R (Ramsdell notation). Intensity distributions were calculated based on the Zhdanov notation of (33) for 6H and [ (33)3 (32)2 ]3 for 84R. Because of the dynamical effect in electron diffraction, the observed intensities do not exactly coincide with those intensities obtained by structure factor calculations. Fig. 2 shows the high resolution TEM micrographs, where the striped patterns correspond to direct resolution of the structural lattice periodicities of 6H and 84R structures and the spacings shown in the figures are as expected for those structures.

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