Simultaneous measurements of the fluid and the solid phases in homogeneous turbulence: preliminary results at Re λ = 250

AbstractWe have conducted a series of experiments at the KMS CHROMA facility using dot spectroscopy techniques to characterize uncertainties associated with spectral line ratio models commonly applied in determining electron temperatures and densities. Temperatures determined from the slope of the H-like free-bound continuum and densities via holographic interferometry, are compared to line ratio methods. Dot targets of (typically 100µmD Mg or Al) are irradiated with 2 to 40 × 1013W/cm2of 0.53µmlight. Time and spatial gradients are resolved using 4 diagnostics: a 4-frame holographic interferometer, an x-ray streak crystal spectrograph with a spatial imaging slit, a framing crystal x-ray spectrometer, and a conventional space-resolved time-integrating crystal spectrograph used for survey and calibration purposes. Preliminary results indicate the ionization distribution of these laser produced plasmas is not steady-state which plays an important role in measuring the temperature and and density. Electron temperatures derived from line-ratio techniques, assuming steady state conditions, disagree dramatically from simultaneous measurements using the slope of the H-like continuum. Electron densities using He-like triplet to singlet line ratios also differ from densities measured interferometrically.

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Local characterization of homogeneous turbulence in a space plasma from simultaneous Measurements of field components at several points in space

Journal of Geophysical Research Atmospheres ◽

10.1029/90ja02183 ◽

1991 ◽

Vol 96 (A2) ◽

pp. 1789-1802 ◽

Cited By ~ 96

Author(s):

Jean Louis Pinçon ◽

François Lefeuvre

Keyword(s):

Space Plasma ◽

Homogeneous Turbulence ◽

Simultaneous Measurements ◽

Local Characterization

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The O–C diagrams of minor planets − a new approach to modelling the rotation

International Astronomical Union Colloquium ◽

10.1017/s0252921100031407 ◽

1999 ◽

Vol 173 ◽

pp. 185-188

Author(s):

Gy. Szabó ◽

K. Sárneczky ◽

L.L. Kiss

Keyword(s):

Error Analysis ◽

Time Dependence ◽

Theoretical Work ◽

Minor Planet ◽

Minor Planets ◽

New Approach ◽

Preliminary Results ◽

Ccd Observations

AbstractA widely used tool in studying quasi-monoperiodic processes is the O–C diagram. This paper deals with the application of this diagram in minor planet studies. The main difference between our approach and the classical O–C diagram is that we transform the epoch (=time) dependence into the geocentric longitude domain. We outline a rotation modelling using this modified O–C and illustrate the abilities with detailed error analysis. The primary assumption, that the monotonity and the shape of this diagram is (almost) independent of the geometry of the asteroids is discussed and tested. The monotonity enables an unambiguous distinction between the prograde and retrograde rotation, thus the four-fold (or in some cases the two-fold) ambiguities can be avoided. This turned out to be the main advantage of the O–C examination. As an extension to the theoretical work, we present some preliminary results on 1727 Mette based on new CCD observations.

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Cyclic Evolution of Sunspots: Gleaning New Results from Old Data

International Astronomical Union Colloquium ◽

10.1017/s0252921100064411 ◽

2000 ◽

Vol 179 ◽

pp. 163-165

Author(s):

S. K. Solanki ◽

M. Fligge ◽

P. Pulkkinen ◽

P. Hoyng

Keyword(s):

Sunspot Number ◽

Sunspot Cycle ◽

Preliminary Results ◽

Butterfly Diagram

AbstractThe records of sunspot number, sunspot areas and sunspot locations gathered over the centuries by various observatories are reanalysed with the aim of finding as yet undiscovered connections between the different parameters of the sunspot cycle and the butterfly diagram. Preliminary results of such interrelationships are presented.

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Systematic effects in observed parallaxes

International Astronomical Union Colloquium ◽

10.1017/s0252921100073887 ◽

1978 ◽

Vol 48 ◽

pp. 31-35

Author(s):

R. B. Hanson

Keyword(s):

Error Estimates ◽

Zero Point ◽

Absolute Zero ◽

Apparent Magnitude ◽

Coherent System ◽

Preliminary Results ◽

General Catalogue ◽

Systematic Effects ◽

New Evidence ◽

Right Ascension

Several outstanding problems affecting the existing parallaxes should be resolved to form a coherent system for the new General Catalogue proposed by van Altena, as well as to improve luminosity calibrations and other parallax applications. Lutz has reviewed several of these problems, such as: (A) systematic differences between observatories, (B) external error estimates, (C) the absolute zero point, and (D) systematic observational effects (in right ascension, declination, apparent magnitude, etc.). Here we explore the use of cluster and spectroscopic parallaxes, and the distributions of observed parallaxes, to bring new evidence to bear on these classic problems. Several preliminary results have been obtained.

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Quantitative Measurements on the Ion Etching of TMV

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100072125 ◽

1973 ◽

Vol 31 ◽

pp. 336-337

Author(s):

Irwin Bendet ◽

Nabil Rizk

Keyword(s):

Electron Microscope ◽

Tobacco Mosaic Virus ◽

Mosaic Virus ◽

Ion Current ◽

Beam Diameter ◽

Ion Etching ◽

Preliminary Results ◽

Quantitative Measurements ◽

Monitoring Devices

Preliminary results reported last year on the ion etching of tobacco mosaic virus indicated that the diameter of the virus decreased more rapidly at 10KV than at 5KV, perhaps reaching a constant value before disappearing completely.In order to follow the effects of ion etching on TMV more quantitatively we have designed and built a second apparatus (Fig. 1), which incorporates monitoring devices for measuring ion current and vacuum as well as accelerating voltage. In addition, the beam diameter has been increased to approximately 1 cm., so that ten electron microscope grids can be exposed to the beam simultaneously.

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Granular bainite or granular ferrite? A preliminary TEM investigation of an HSLA-100 steel

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100087239 ◽

1991 ◽

Vol 49 ◽

pp. 584-585

Author(s):

R. Varughese ◽

S. W. Thompson ◽

P. R. Howell

Keyword(s):

Room Temperature ◽

Transformation Products ◽

Accurate Description ◽

Granular Bainite ◽

Preliminary Results ◽

The Past ◽

Light Micrograph ◽

Multiphase Reaction ◽

Detailed Nature

Ever since Habraken and Economopoulos first employed the term granular bainite to classify certain unconventional transformation products in continuously cooled steels, the term has been widely accepted and used, despite the lack of a clear consensus as to the detailed nature of the transformation products which constitute granular bainite. This paper presents the preliminary results of a TEM investigation of an 0.04 wt% C, copper-containing steel (designated HSLA-100). It is suggested that the term granular ferrite rather than granular bainite is a more accurate description of this multiphase reaction product.Figure 1 is a light micrograph of a sample which had been air-cooled from 900°C to room temperature. The microstructure is typical of that which has been termed granular bainite in the past and appears to consist of equiaxed ferritic grains together with other minor transformation products. In order to examine these structures in more detail, both continuously cooled and isothermally transformed and quenched materials have been examined with TEM. Granular bainite has been found in virtually all samples.

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