CHARACTERISTICS AND GENESIS OF BRUNISOLIC SOILS OF NORTHERN ALBERTA

1964 ◽  
Vol 44 (3) ◽  
pp. 292-303 ◽  
Author(s):  
S. Pawluk ◽  
J. D. Lindsay
Keyword(s):  
Electron Microscope ◽  
Iron Oxide ◽  
National Park ◽  
Common Occurrence ◽  
X Ray ◽  
Physical Chemical ◽  
Wood Buffalo National Park ◽  
Pellet Form ◽  
Northern Alberta ◽  
Soil Groups

Exploratory surveys of the Wood Buffalo National Park in Northern Alberta revealed the presence of vast tracts of brunisolic soils. These soils are of common occurrence in the low plains area adjacent to Lake Clare.The brunisolic soils included in this study belong to the Brown Forest, Brown Wooded, and Acid Brown Wooded Great Soil Groups. All profiles were characterized with respect to their physical, chemical, and mineralogical properties. Special attention was directed to the Bf horizons where magnetic, amorphous (to X-ray) humus–iron micropellets were identified with the use of an electron microscope. The release of iron oxide from the weathering of iron-rich chlorites was also evident and is suggested as a mechanism by which the accretion of iron oxide to a pellet form could be explained. The possible genesis of these micropellets is fully discussed.

An occurrence of phlogopite and its transformation to vermiculite by weathering

1965 ◽  
Vol 35 (269) ◽  
pp. 151-164 ◽  
Author(s):  
W. W. Smith Aitken
Keyword(s):  
Thin Films ◽  
Electron Microscope ◽  
Iron Oxide ◽  
Single Crystal ◽  
Orientation Relationship ◽  
Preferred Orientation ◽  
Chemical Methods ◽  
X Ray ◽  
Infra Red

SummaryThe characteristics of a phlogopite and its weathering product, vermiculite, have been studied by X-ray, infra-red, electron-microscope, and chemical methods. Inclusions within these minerals have been identified as thin films rich in iron oxide (which impart a schiller effect), spinel (which may exist in a preferred orientation), and serpentine. The orientation relationship between the fresh mica and its weathering product has been established by single-crystal methods. The mechanism of transformation from a 1-layer to a 2-layer polytype is discussed.

Effect of Annealing on Structural Properties of Fe3O4 Ferrite Nanoparticles

2018 ◽  
Vol 24 (8) ◽  
pp. 5748-5751
Author(s):  
Ravita ◽  
Amita ◽  
Ashok Kumar ◽  
Pawan S Rana
Keyword(s):  
Particle Size ◽  
Electron Microscope ◽  
Iron Oxide ◽  
Structural Properties ◽  
Iron Oxide Nanoparticles ◽  
Annealing Treatment ◽  
Precipitation Method ◽  
Oxide Nanoparticles ◽  
X Ray Diffraction ◽  
X Ray

Nano-crystalline Fe3O4 particles has been synthesized by chemical co-precipitation method. The synthesized samples were annealed at different temperature 300 °C, 500 °C, 700 °C. The effect of annealing temperature on structural properties of synthesized sample has been studied by various analytical techniques like X-ray diffraction (XRD), scanning electron microscope (SEM), transmission electron microscope and Fourier transform infrared spectroscopy (FTIR). The X-ray diffraction patterns confirm the synthesis of single crystalline phase of Fe3O4 nanoparticles. The crystallite size of synthesized iron oxide nanoparticles is about 7 nm. The crystallinity of iron oxide nanoparticles is enhanced by annealing treatment which is also confirmed by corresponding SEM and TEM micrographs. A phase transition from magnetite (Fe3O4) to hematite (α-F2O3) is observed when the samples are annealed above 500 °C. The fundamental groups of the iron oxide and annealed samples have been identified from FTIR spectrum. The particle size calculated from TEM images for the Fe3O4 sample varies in the range 5–20 nm and it has been observed that the particle size increases on annealing.

The biology of Canadian weeds. 98 Potentilla anserina L.

1991 ◽  
Vol 71 (3) ◽  
pp. 791-801 ◽  
Author(s):  
K. Miyanishi ◽  
O. Eriksson ◽  
R. W. Wein
Keyword(s):  
National Park ◽  
Original Data ◽  
Disturbance Ecology ◽  
Review Of The Literature ◽  
Potentilla Anserina ◽  
Wood Bison ◽  
Sedge Meadows ◽  
Wood Buffalo National Park ◽  
Northern Alberta ◽  
Herbaceous Perennial

Potentilla anserina L., silverweed (Rosaceae), occurs in all provinces of Canada as well as in the two territories. Although generally found in wet sandy areas along rivers and on beaches, silverweed also occurs in waste areas, along roadsides, and in lawns. This shade-intolerant stoloniferous plant has recently become dominant in overgrazed sedge meadows of the Peace-Athabasca Delta, resulting in deterioration of portions of the primary range for wood bison in Wood Buffalo National Park in northern Alberta. This contribution presents both a review of the literature and some original data on the biology and ecology of the species. Key words: Silverweed, disturbance, ecology, herbaceous perennial, demography

scholarly journals Utilization of Neem Leaf Extract on Biosynthesis of Iron Oxide Nanoparticles

Molecules ◽  
2019 ◽  
Vol 24 (20) ◽  
pp. 3803 ◽  
Author(s):  
Nur Diyana Syazwani Zambri ◽  
Nurul Izza Taib ◽  
Famiza Abdul Latif ◽  
Zakiah Mohamed
Keyword(s):  
Electron Microscope ◽  
Iron Oxide ◽  
Iron Oxide Nanoparticles ◽  
Magnetite Nanoparticles ◽  
Leaf Extract ◽  
Xrd Analysis ◽  
Oxide Nanoparticles ◽  
Spectra Analysis ◽  
X Ray ◽  
Average Size

The present work reports the successful synthesis of biosynthesized iron oxide nanoparticles (Fe3O4-NPs) with the use of non-toxic leaf extract of Neem (Azadirachta indica) as a reducing and stabilizing agent. The successful synthesis was confirmed by infrared spectra analysis with strong peak observed between 400–600 cm−1 that corresponds to magnetite nanoparticles characteristics. X-ray diffraction (XRD) analysis revealed that iron oxide nanoparticles were of high purity with crystalline cubic structure phases in nature. Besides, the average size of magnetite nanoparticles was observed to be 9–12 nm with mostly irregular shapes using a transmission electron microscope (TEM) and was supported by field emission scanning electron microscope (FESEM). Energy dispersive X-ray analysis shown that the elements iron (Fe) and oxygen (O) were present with atomic percentages of 33.29% and 66.71%, respectively. From the vibrating sample magnetometer (VSM) analysis it was proven that the nanoparticles exhibited superparamagnetic properties with a magnetization value of 73 emu/g and the results showed superparamagnetic behavior at room temperature, suggesting potential applications for a magnetic targeting drug delivery system.

X-ray microanalysis of thin specimens in the transmission electron microscope at voltages up to 1000 Kv.

1978 ◽  
Vol 36 (1) ◽  
pp. 540-541
Author(s):  
G. Cliff ◽  
M.J. Nasir ◽  
G.W. Lorimer ◽  
N. Ridley
Keyword(s):  
Electron Microscope ◽  
Transmission Electron Microscope ◽  
Weight Fraction ◽  
Present Series ◽  
Constant Independent ◽  
X Ray ◽  
Transmission Electron ◽  
Series Of Experiments ◽  
Image Position ◽  
X Ray Absorption

In a specimen which is transmission thin to 100 kV electrons - a sample in which X-ray absorption is so insignificant that it can be neglected and where fluorescence effects can generally be ignored (1,2) - a ratio of characteristic X-ray intensities, I1/I2 can be converted into a weight fraction ratio, C1/C2, using the equationwhere k12 is, at a given voltage, a constant independent of composition or thickness, k12 values can be determined experimentally from thin standards (3) or calculated (4,6). Both experimental and calculated k12 values have been obtained for K(11<Z>19),kα(Z>19) and some Lα radiation (3,6) at 100 kV. The object of the present series of experiments was to experimentally determine k12 values at voltages between 200 and 1000 kV and to compare these with calculated values.The experiments were carried out on an AEI-EM7 HVEM fitted with an energy dispersive X-ray detector.

Aspects of microanalysis in a transmission electron microscope

1978 ◽  
Vol 36 (1) ◽  
pp. 510-511
Author(s):  
R. Sinclair ◽  
B.E. Jacobson
Keyword(s):  
Grain Size ◽  
Electron Beam ◽  
Electron Microscope ◽  
Chemical Analysis ◽  
Transmission Electron Microscope ◽  
Vapor Deposition ◽  
Critical Currents ◽  
X Ray ◽  
Fine Grain ◽  
Transmission Electron

INTRODUCTIONThe prospect of performing chemical analysis of thin specimens at any desired level of resolution is particularly appealing to the materials scientist. Commercial TEM-based systems are now available which virtually provide this capability. The purpose of this contribution is to illustrate its application to problems which would have been intractable until recently, pointing out some current limitations.X-RAY ANALYSISIn an attempt to fabricate superconducting materials with high critical currents and temperature, thin Nb3Sn films have been prepared by electron beam vapor deposition [1]. Fine-grain size material is desirable which may be achieved by codeposition with small amounts of Al2O3 . Figure 1 shows the STEM microstructure, with large (∽ 200 Å dia) voids present at the grain boundaries. Higher quality TEM micrographs (e.g. fig. 2) reveal the presence of small voids within the grains which are absent in pure Nb3Sn prepared under identical conditions. The X-ray spectrum from large (∽ lμ dia) or small (∽100 Ǻ dia) areas within the grains indicates only small amounts of A1 (fig.3).

Thickness and composition determinations from T.E.M. specimens using both x-ray and backscattered electron data

1984 ◽  
Vol 42 ◽  
pp. 576-577
Author(s):  
M.D. Ball ◽  
H. Lagace ◽  
M.C. Thornton
Keyword(s):  
Electron Microscope ◽  
Atomic Number ◽  
Transmission Electron Microscope ◽  
Convenient Method ◽  
Flow Chart ◽  
X Ray ◽  
Intensity Measurements ◽  
Transmission Electron ◽  
Electron Intensity ◽  
Backscattered Electron

The backscattered electron coefficient η for transmission electron microscope specimens depends on both the atomic number Z and the thickness t. Hence for specimens of known atomic number, the thickness can be determined from backscattered electron coefficient measurements. This work describes a simple and convenient method of estimating the thickness and the corrected composition of areas of uncertain atomic number by combining x-ray microanalysis and backscattered electron intensity measurements.The method is best described in terms of the flow chart shown In Figure 1. Having selected a feature of interest, x-ray microanalysis data is recorded and used to estimate the composition. At this stage thickness corrections for absorption and fluorescence are not performed.

X-ray micro tomography in the scanning electron microscope

1978 ◽  
Vol 36 (1) ◽  
pp. 106-107 ◽  
Author(s):  
W. Brünger
Keyword(s):  
Electron Beam ◽  
Electron Microscope ◽  
Scanning Electron Microscope ◽  
Target Surface ◽  
The Body ◽  
X Rays ◽  
Cross Sectional ◽  
X Ray ◽  
Micro Tomography ◽  
Scanning Electron

Reconstructive tomography is a new technique in diagnostic radiology for imaging cross-sectional planes of the human body /1/. A collimated beam of X-rays is scanned through a thin slice of the body and the transmitted intensity is recorded by a detector giving a linear shadow graph or projection (see fig. 1). Many of these projections at different angles are used to reconstruct the body-layer, usually with the aid of a computer. The picture element size of present tomographic scanners is approximately 1.1 mm2.Micro tomography can be realized using the very fine X-ray source generated by the focused electron beam of a scanning electron microscope (see fig. 2). The translation of the X-ray source is done by a line scan of the electron beam on a polished target surface /2/. Projections at different angles are produced by rotating the object.During the registration of a single scan the electron beam is deflected in one direction only, while both deflections are operating in the display tube.

point-Analysis Using the Extrapolation Method in the Analytical Electron microscope

1990 ◽  
Vol 48 (2) ◽  
pp. 430-431
Author(s):  
Zenji Horita ◽  
Ryuzo Nishimachi ◽  
Takeshi Sano ◽  
Minoru Nemoto
Keyword(s):  
Electron Microscope ◽  
Extrapolation Method ◽  
X Ray ◽  
Absorption Correction ◽  
Point Analysis ◽  
Analytical Electron ◽  
Analytical Electron Microscope ◽  
Data Points ◽  
Identical Composition ◽  
X Ray Absorption

Absorption correction is often required in quantitative x-ray microanalysis of thin specimens using the analytical electron microscope. For such correction, it is convenient to use the extrapolation method[l] because the thickness, density and mass absorption coefficient are not necessary in the method. The characteristic x-ray intensities measured for the analysis are only requirement for the absorption correction. However, to achieve extrapolation, it is imperative to obtain data points more than two at different thicknesses in the identical composition. Thus, the method encounters difficulty in analyzing a region equivalent to beam size or the specimen with uniform thickness. The purpose of this study is to modify the method so that extrapolation becomes feasible in such limited conditions. Applicability of the new form is examined by using a standard sample and then it is applied to quantification of phases in a Ni-Al-W ternary alloy.The earlier equation for the extrapolation method was formulated based on the facts that the magnitude of x-ray absorption increases with increasing thickness and that the intensity of a characteristic x-ray exhibiting negligible absorption in the specimen is used as a measure of thickness.

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