A New Hot Stage for the Philips EM 200 and Its Calibration

1968 ◽  
Vol 26 ◽  
pp. 312-313
Author(s):  
J. W. Sprys ◽  
P. C. J. Gallagher
Keyword(s):  
Electron Microscope ◽  
Defect Structure ◽  
Full Range ◽  
Temperature Cycling ◽  
List Type ◽  
Thermal Coupling ◽  
Type Number ◽  
Specimen Area ◽  
Degree Of Stability ◽  
High Degree

A hot stage for use in metallurgical investigations with the electron microscope should have several, if not all, of the following characteristics.The specimen temperature should be measurable with accuracy over the full range of operation of the stage.The stage should allow a large tilt angle for diffraction and contrast work.The stage should not restrict expansion of the sample during temperature cycling thus avoiding alteration to the sample's defect structure from the presence of thermal stress.The heater and sample should approach equilibrium rapidly after any change in temperature, with a minimum of drift during the change, and a high degree of stability at temperature.The stage should permit study of as much of the thinned specimen area as is possible compatible with adequate thermal coupling to the furnace.

Electron Microscope Observations of Mechanical Metamorphism in Iron Meteorites

1970 ◽  
Vol 28 ◽  
pp. 488-489
Author(s):  
D. Faulkner ◽  
G.W. Lorimer ◽  
H.J. Axon
Keyword(s):  
Electron Microscope ◽  
Defect Structure ◽  
Shock Loading ◽  
List Type ◽  
Iron Meteorites

It is now generally accepted that meteorites are fragments produced by the collision of parent bodies of asteroidal dimensions. Optical metallographic evidence suggests that there exists a group of iron meteorites which exhibit structures similar to those observed in explosively shock loaded iron. It seems likely that shock loading of meteorites could be produced by preterrestrial impact of their parent bodies as mentioned above.We have therefore looked at the defect structure of one of these meteorites (Trenton) and compared the results with those made on a) an unshocked ‘standard’ meteorite (Canyon Diablo)b) an artificially shocked ‘standard’ meteorite (Canyon Diablo) andc) an artificially shocked specimen of pure α-iron.

Hydration Chamber for Jeolco 200 Kv Microscope

1970 ◽  
Vol 28 ◽  
pp. 542-543
Author(s):  
V. R. Matricardi ◽  
G. G. Hausner ◽  
D. F. Parsons
Keyword(s):  
Electron Microscope ◽  
Water Vapor ◽  
Vapor Pressure ◽  
Pressure Gradient ◽  
Room Temperature ◽  
List Type ◽  
Type Number ◽  
Equilibrium Vapor Pressure

In order to observe room temperature hydrated specimens in an electron microscope, the following conditions should be satisfied: The specimen should be surrounded by water vapor as close as possible to the equilibrium vapor pressure corresponding to the temperature of the specimen.The specimen grid should be inserted, focused and photo graphed in the shortest possible time in order to minimize dehydration.The full area of the specimen grid should be visible in order to minimize the number of changes of specimen required.There should be no pressure gradient across the grid so that specimens can be straddled across holes.Leakage of water vapor to the column should be minimized.

Breeding

1935 ◽  
Vol 8 (4) ◽  
pp. 54-80
Keyword(s):  
Low Temperature ◽  
Moisture Content ◽  
Early Stage ◽  
Control Group ◽  
List Type ◽  
Type Number ◽  
Depressing Effect ◽  
Internal Organs ◽  
Completely Regular ◽  
High Degree

Growth of Chicken-Embryos. Das Wachstum des Hühnerembryos in Abhängigkeit von verschiedenen Temperaturen und Feuchtigkeitsgraden im Brutapparat. N. M. Schkljar. Archiv für Geflügelkunde, 1935, No. 5.Summary:1.A completely regular and strong growth of the hen embryos is obtained with a temperature of 38.4° C. (101.1° F.) and 64% moisture.2.A temperature of 39.9° C. (103.82° F.) and 62% moisture have a somewhat depressing effect on the developement of the embryos during the first six and last two days of the incubation, an increase in growth taking place on the 16th days.3.A high degree of moisture of 77% and a temperature of 38.3 ° C. (100.9° F.) prevent growth up to the 18th day, a decisive increase taking place after this date.4.With a low temperature of 37° C. (98.66° F.) and a moisture content of 63%, the developement of embryos remains noticeably backward, specially during the first few days. Under such conditions, as early as after the sixth day, growth in relation to the control group is delayed by two days.5.Between the increase in weigth and the developement of embryos, there exists, in an early stage, an inverted ratio of dependance.6.The rate of growth of the internal organs is not a process working within itself, but subject to the general conformity to law.7.The growth of the embryo is not the result of an uninterruped developement, but consists of a sequence of increases and depressions.

Toward the biochemistry of individual molecules

1984 ◽  
Vol 42 ◽  
pp. 154-157
Author(s):  
J. S. Wall ◽  
J. F. Hainfeld
Keyword(s):  
Electron Microscope ◽  
Active Sites ◽  
Scanning Transmission Electron Microscope ◽  
List Type ◽  
Type Number ◽  
Low Contrast ◽  
Transmission Electron ◽  
Scanning Transmission ◽  
Conventional Microscopy ◽  
Detailed Interpretation

One goal of the Brookhaven STEM group is to enhance the capabilities of the electron microscope as a biochemical tool, while attempting to open up a new field: the Biochemistry of Individual Molecules. Three aspects of molecular biology seem particularly tractable with the STEM (Scanning Transmission Electron Microscope):Size, shape and molecular weightActive sites: location and environmentInteractions in complex systemsAll these areas have been explored to some extent by conventional microscopy, but definitive conclusions are elusive because of low contrast and radiation damage which usually require staining or shadowing to “see” anything. Periodic features may be rendered faithfully, but detailed interpretation falls prey to arguments about positive vs. negative staining, decoration vs. shadowing, flattening, shrinkage, and other such phenomenon.

scholarly journals Recent Developments in Improving Daytime Angular Resolution from the Ground

1974 ◽  
Vol 56 ◽  
pp. 27-30 ◽  
Author(s):  
K. O. Kiepenheuer
Keyword(s):  
Angular Resolution ◽  
Solar Chromosphere ◽  
List Type ◽  
Type Number ◽  
Modulation Transfer ◽  
Recent Developments ◽  
The Subject ◽  
High Degree ◽  
Atmospheric Seeing

The subject of this symposium is the fine structure of the solar chromosphere. Progress in this field of reserach will depend to a high degree of the quality of seeing, resp. on the effective angular resolution available on the ground. Today's situation of solar ground seeing has changed distinctly in the last years. I would like to report here a few new aspects, which could be condensed into 3 questions: (1)Are there on the ground ‘good seeing windows’, comparable in quality with stratosphere results obtained from balloon borne equipment?(2)Is there a chance to resolve from the ground the solar scale height, corresponding to about 0.1″.(3)Is there a residual fundamental atmospheric seeing noise resp. a basic limit to the atmospheric Modulation Transfer Function (MTF)?

Solar Corona Investigation by the Coronal Line Photometer at Lomnický Peak

1994 ◽  
Vol 144 ◽  
pp. 431-434
Author(s):  
M. Minarovjech ◽  
M. Rybanský
Keyword(s):  
Solar Corona ◽  
Time Resolution ◽  
Active Regions ◽  
High Time ◽  
High Time Resolution ◽  
List Type ◽  
Type Number ◽  
Coronal Line ◽  
Global Cycle

AbstractThis paper deals with a possibility to use the ground-based method of observation in order to solve basic problems connected with the solar corona research. Namely:1.heating of the solar corona2.course of the global cycle in the corona3.rotation of the solar corona and development of active regions.There is stressed a possibility of high-time resolution of the coronal line photometer at Lomnický Peak coronal station, and use of the latter to obtain crucial observations.

The LDE-Type Flare Occurrence (1969-1993)

1994 ◽  
Vol 144 ◽  
pp. 279-282
Author(s):  
A. Antalová
Keyword(s):  
Time Series ◽  
Fourier Analysis ◽  
Sunspot Cycle ◽  
List Type ◽  
Type Number ◽  
Solar Cycles ◽  
Type Iv ◽  
Long Duration ◽  
Cycle Maximum ◽  
Flare Index

AbstractThe occurrence of LDE-type flares in the last three cycles has been investigated. The Fourier analysis spectrum was calculated for the time series of the LDE-type flare occurrence during the 20-th, the 21-st and the rising part of the 22-nd cycle. LDE-type flares (Long Duration Events in SXR) are associated with the interplanetary protons (SEP and STIP as well), energized coronal archs and radio type IV emission. Generally, in all the cycles considered, LDE-type flares mainly originated during a 6-year interval of the respective cycle (2 years before and 4 years after the sunspot cycle maximum). The following significant periodicities were found:• in the 20-th cycle: 1.4, 2.1, 2.9, 4.0, 10.7 and 54.2 of month,• in the 21-st cycle: 1.2, 1.6, 2.8, 4.9, 7.8 and 44.5 of month,• in the 22-nd cycle, till March 1992: 1.4, 1.8, 2.4, 7.2, 8.7, 11.8 and 29.1 of month,• in all interval (1969-1992):a)the longer periodicities: 232.1, 121.1 (the dominant at 10.1 of year), 80.7, 61.9 and 25.6 of month,b)the shorter periodicities: 4.7, 5.0, 6.8, 7.9, 9.1, 15.8 and 20.4 of month.Fourier analysis of the LDE-type flare index (FI) yields significant peaks at 2.3 - 2.9 months and 4.2 - 4.9 months. These short periodicities correspond remarkably in the all three last solar cycles. The larger periodicities are different in respective cycles.

Discussion following the presentation by F. Deubner

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.

Prominences and Solar Activity

1979 ◽  
Vol 44 ◽  
pp. 357-372
Author(s):  
Z. Švestka
Keyword(s):  
Solar Activity ◽  
Solar Cycle ◽  
List Type ◽  
Type Number ◽  
Flare Loops ◽  
Filament Activation

The following subjects were discussed:(1)Filament activation(2)Post-flare loops.(3)Surges and sprays.(4)Coronal transients.(5)Disk vs. limb observations.(6)Solar cycle variations of prominence occurrence.(7)Active prominences patrol service.Of all these items, (1) and (2) were discussed in most detail and we also pay most attention to them in this report. Items (3) and (4) did not bring anything new when compared with the earlier invited presentations given by RUST and ZIRIN and therefore, we omit them.

A New System For Optomanual Semiautomatic Quantitative Image Analysis

1977 ◽  
Vol 35 ◽  
pp. 210-211
Author(s):  
H.P. Rohr
Keyword(s):  
Image Analysis ◽  
Volume Density ◽  
List Type ◽  
Distribution Analysis ◽  
Type Number ◽  
Point Counting ◽  
Human Eye ◽  
Quantitative Image ◽  
Point Density ◽  
Electronic Counting

Today, in image analysis the broadest possible rationalization and economization have become desirable. Basically, there are two approaches for image analysis: The image analysis through the so-called scanning methods which are usually performed without the human eye and the systems of optical semiautomatic analysis completely relying on the human eye.The new MOP AM 01 opto-manual system (fig.) represents one of the very promising approaches in this field. The instrument consists of an electronic counting and storing unit, which incorporates a microprocessor and a keyboard for choice of measuring parameters, well designed for easy use.Using the MOP AM 01 there are three possibilities of image analysis:the manual point counting,the opto-manual point counting andthe measurement of absolute areas and/or length (size distribution analysis included).To determine a point density for the calculation of the corresponding volume density the intercepts lying within the structure are scanned with the light pen.

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