scholarly journals Seismic cross sections across the Spokane River valley and the Hillyard Trough, Idaho and Washington

1953 ◽  
Author(s):  
R.C. Newcomb ◽  
Keyword(s):  
Cross Sections ◽  
River Valley ◽  
Spokane River

scholarly journals The Cross Sections of Glaciated Valleys

1947 ◽  
Vol 1 (1) ◽  
pp. 37-38 ◽  
Author(s):  
W. V. Lewis
Keyword(s):  
Climatic Change ◽  
Cross Section ◽  
Cross Sections ◽  
River Valley ◽  
Freezing And Thawing ◽  
Melt Water ◽  
The Cross ◽  
Shaped Cross Section

The typical U-shaped cross-section of glaciated valleys is well known but little understood. If a climatic change results in a glacier occupying a deep river valley, and some erosion is assumed to occur wherever the ice makes contact with the bedrock, then a partial change from the “V” to “U” section is to be expected. A more potent agency in such a change is probably the sapping of the valley sides by the alternate freezing and thawing of melt-water flowing down to, and under, the glacier. This has been briefly suggested by de Martonne and worked out somewhat more fully in the case of cirques1

The Cross Sections of Glaciated Valleys

1947 ◽  
Vol 1 (01) ◽  
pp. 37-38 ◽  
Author(s):  
W. V. Lewis
Keyword(s):  
Climatic Change ◽  
Cross Section ◽  
Cross Sections ◽  
River Valley ◽  
Freezing And Thawing ◽  
Melt Water ◽  
The Cross ◽  
Shaped Cross Section

The typical U-shaped cross-section of glaciated valleys is well known but little understood. If a climatic change results in a glacier occupying a deep river valley, and some erosion is assumed to occur wherever the ice makes contact with the bedrock, then a partial change from the “V” to “U” section is to be expected. A more potent agency in such a change is probably the sapping of the valley sides by the alternate freezing and thawing of melt-water flowing down to, and under, the glacier. This has been briefly suggested by de Martonne and worked out somewhat more fully in the case of cirques 1

scholarly journals Syngenetic and cyclical yedoma strata of Northern Yakutia

2020 ◽  
pp. 34-64
Author(s):  
Yurij Kirillovich Vasil'chuk
Keyword(s):  
Cross Sections ◽  
Sandy Loam ◽  
River Valley ◽  
Approximate Determination ◽  
Ice Wedge ◽  
The Subject

This article demonstrates the evolution of representation on syngenetic formation of frozen strata set by Lopatin, Abolin, Leffingwell and Nekipelov. It is underlined that the theory of syngenesis is substantiated by the works of Gallwitz, Popov and Katasonov. It is mentioned that Dostovalov proposed a method for approximate determination of the age of ice-wedge ice and calculated that 3m wide ice wedges in the vicinity of Abalakh Lake are older than 2160 years, and 30-40 m high ice wedges in the Novosibirsk islands are older than 12,000 years according to Dostovalov’s calculations. The subject of the detailed study is the meso- and macro- cycles in the structure of yedoma strata in Northern Yakutia. Mesocycles in the yedoma strata of the Zelyony Mys, Stanchikovsky Yar, and Batagay have been examined, along with macrocycles of the Batagay yedoma. The mesocyclicity of the cryolithogenic strata is analyzed in the following cross sections: in Bolshoy Lyakhovsky Island, yedoma in the Belyanka River valley, in the outcrop Soplivaya Gora in the Yana River valley, in the valley of the Vilyuy River downstream of Verkhnevilyuysk, etc. The duration of the mesocycles formation in the yedoma strata of the Northern Yakutia is established: a. One subaquatic-subaerial mesocycle in the Zelyony Mys yedoma consisting of a subaquatic sandy loam and a subaerial peaty horizon of 4 m thick accumulated over the period 3,000years. b. One subaquatic-subaerial mesocycle in the Stanchikovsky Yar yedoma 5 m thick accumulated over the period of 3,300 years. c. One mesocycle in the section Soplivaya Gora, in the Yana River valley with a capacity of 3 m formed for about 3.000 years. Three macrocycles are identified in the Batagay section, with capacity of 7, 10 and 40 m; the time of formation of each macrocycle varied from 15-20 to 40 thousand years or more.

Analysis of STEM micrographs of thick objects

1978 ◽  
Vol 36 (2) ◽  
pp. 106-107
Author(s):  
S. Golladay
Keyword(s):  
Inelastic Scattering ◽  
Multiple Scattering ◽  
Mass Distribution ◽  
Cross Sections ◽  
Phase Contrast ◽  
Image Point ◽  
Contrast Effects ◽  
Total Cross Sections ◽  
Elastic And Inelastic Scattering

The theory of multiple scattering has been worked out by Groves and comparisons have been made between predicted and observed signals for thick specimens observed in a STEM under conditions where phase contrast effects are unimportant. Independent measurements of the collection efficiencies of the two STEM detectors, calculations of the ratio σe/σi = R, where σe, σi are the total cross sections for elastic and inelastic scattering respectively, and a model of the unknown mass distribution are needed for these comparisons. In this paper an extension of this work will be described which allows the determination of the required efficiencies, R, and the unknown mass distribution from the data without additional measurements or models. Essential to the analysis is the fact that in a STEM two or more signal measurements can be made simultaneously at each image point.

Direct Observation of Heat Exchanger Deposits by Cross Sectioning

1967 ◽  
Vol 25 ◽  
pp. 364-365
Author(s):  
R. W. Anderson ◽  
D. L. Senecal
Keyword(s):  
Electron Microscopy ◽  
Transmission Electron Microscopy ◽  
Heat Exchanger ◽  
Direct Observation ◽  
Cross Sections ◽  
Preparation Method ◽  
Specimen Preparation ◽  
Flowing Water ◽  
Transmission Electron ◽  
Deposit Layer

A problem was presented to observe the packing densities of deposits of sub-micron corrosion product particles. The deposits were 5-100 mils thick and had formed on the inside surfaces of 3/8 inch diameter Zircaloy-2 heat exchanger tubes. The particles were iron oxides deposited from flowing water and consequently were only weakly bonded. Particular care was required during handling to preserve the original formations of the deposits. The specimen preparation method described below allowed direct observation of cross sections of the deposit layers by transmission electron microscopy.The specimens were short sections of the tubes (about 3 inches long) that were carefully cut from the systems. The insides of the tube sections were first coated with a thin layer of a fluid epoxy resin by dipping. This coating served to impregnate the deposit layer as well as to protect the layer if subsequent handling were required.

An Analysis of Dissociation of Molecules in a High Resolution Electron Microscope

1973 ◽  
Vol 31 ◽  
pp. 486-487
Author(s):  
Mihir Parikh
Keyword(s):  
Electron Microscope ◽  
High Resolution ◽  
Cross Sections ◽  
Resolving Power ◽  
Peak Intensity ◽  
Molecular Film ◽  
Resolution Electron ◽  
Dissociation Cross Section ◽  
High Resolution Electron Microscope ◽  
The Stability

It is well known that the resolution of bio-molecules in a high resolution electron microscope depends not just on the physical resolving power of the instrument, but also on the stability of these molecules under the electron beam. Experimentally, the damage to the bio-molecules is commo ly monitored by the decrease in the intensity of the diffraction pattern, or more quantitatively by the decrease in the peaks of an energy loss spectrum. In the latter case the exposure, EC, to decrease the peak intensity from IO to I’O can be related to the molecular dissociation cross-section, σD, by EC = ℓn(IO /I’O) /ℓD. Qu ntitative data on damage cross-sections are just being reported, However, the microscopist needs to know the explicit dependence of damage on: (1) the molecular properties, (2) the density and characteristics of the molecular film and that of the support film, if any, (3) the temperature of the molecular film and (4) certain characteristics of the electron microscope used

Surface ultrastructure of danazol treated rat endometrium: A SEM study

1983 ◽  
Vol 41 ◽  
pp. 556-557
Author(s):  
R.P. Apkarian ◽  
J.S. Sanfilippo
Keyword(s):  
Cross Sections ◽  
Reproductive Tract ◽  
Preliminary Investigation ◽  
Breast Disease ◽  
Distal Segment ◽  
Uterine Horn ◽  
Female Reproductive Tract ◽  
Ultrastructural Changes ◽  
Cycle Phase ◽  
Sprague Dawley

The synthetic androgen danazol, is an isoxazol derivative of ethisterone. It is utilized in the treatment of endometriosis, fibrocystic breast disease, and has a potential use as a contraceptive. A study was designed to evaluate the ultrastructural changes associated with danazol therapy in a rat model. The preliminary investigation of the distal segment of the rat uterine horn was undertaken as part of a larger study intended to elucidate the effects of danazol on the female reproductive tract.Cross-sections (2-3 mm in length) of the distal segment of the uterine horn from sixteen Sprague-Dawley rats were prepared for SEM. Ten rats in estrus served as controls and six danazol treated rats were noted to have alterations of the estrus cycle i.e. a lag in cycle phase or noncycling patterns. Specimens were fixed in 3% glutaraldehyde in 0.05M phosphate buffer containing CaCl2 at pH 7.0-7.4 and chilled to 4°C. After a brief wash in distilled water, specimens were passed through a graded series of ethanol, critical point dryed in CO2 from absolute ethanol, and coated with 6nm Au. Observations were made with an IS1-40 SEM operated at 15kV.

Electron Irradiation Effects in Polyoxymethylene Crystals Grown Inside Trioxane Crystals

1971 ◽  
Vol 29 ◽  
pp. 78-79
Author(s):  
J. P. Colson ◽  
D. H. Reneker
Keyword(s):  
Cross Section ◽  
Cross Sections ◽  
Detailed Examination ◽  
The Other ◽  
Electron Micrograph ◽  
Irradiation Effects ◽  
Threefold Axis ◽  
Typical Sample ◽  
Polymer Crystals ◽  
Chain Axis

Polyoxymethylene (POM) crystals grow inside trioxane crystals which have been irradiated and heated to a temperature slightly below their melting point. Figure 1 shows a low magnification electron micrograph of a group of such POM crystals. Detailed examination at higher magnification showed that three distinct types of POM crystals grew in a typical sample. The three types of POM crystals were distinguished by the direction that the polymer chain axis in each crystal made with respect to the threefold axis of the trioxane crystal. These polyoxymethylene crystals were described previously.At low magnifications the three types of polymer crystals appeared as slender rods. One type had a hexagonal cross section and the other two types had rectangular cross sections, that is, they were ribbonlike.

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