scholarly journals Magnetoplasmon Excitations at Graphene Vortex Hall Fluid Edge

2016 ◽  
Vol 2016 ◽  
pp. 1-5
Author(s):  
M. Rabiu ◽  
S. Y. Mensah ◽  
I. Y. Seini ◽  
S. S. Abukari
Keyword(s):  
Resonant Mode ◽  
Present Observation ◽  
Vortex Matter ◽  
Experimental Conditions ◽  
Anomalous Term ◽  
Fluid Boundary ◽  
Sharp Edges ◽  
Qualitative Effect ◽  
Second Peak ◽  
Graphene Edge

We investigate magnetoplasmon dynamics localized on the edges of graphene vortex Hall fluid. The vortex matter captures an anomalous term that causes vortex localization near fluid boundary and creates a double boundary layer, Δ0∝(β-1)lB with β being filling factor. The term also has qualitative effect on resonant excitations of edge magnetoplasmons. We found that, for sharp edges under experimental conditions, graphene edge magnetoplasmon (EMP) resonances have similar behavior as in recent experiments. Gradual distinctions arise for smooth edges in the presence of the anomalous term, where a weak EMP peak appears. The second peak becomes well noticed as the smoothness is increased. We identified the resonant mode as an Inter-EMP. It originates from the oscillations of charges in the inner boundary of the double layer. The present observation brings to light the direct cause of Inter-EMP which remained to be detected in graphene experiments.

Electrolytic Isolation of Twin-Type Shock Deformation Structures

1967 ◽  
Vol 25 ◽  
pp. 318-319
Author(s):  
F. I. Grace ◽  
L. E. Murr
Keyword(s):  
Grain Boundaries ◽  
Thin Foil ◽  
Electrolyte Composition ◽  
Experimental Conditions ◽  
Average Current Density ◽  
Electron Transmission ◽  
Deformation Structures ◽  
The Matrix ◽  
Average Current ◽  
Specimen Edge

During the course of electron transmission investigations of the deformation structures associated with shock-loaded thin foil specimens of 70/30 brass, it was observed that in a number of instances preferential etching occurred along grain boundaries; and that the degree of etching appeared to depend upon the various experimental conditions prevailing during electropolishing. These included the electrolyte composition, the average current density, and the temperature in the vicinity of the specimen. In the specific case of 70/30 brass shock-loaded at pressures in the range 200-400 kilobars, the predominant mode of deformation was observed to be twin-type faults which in several cases exhibited preferential etching similar to that observed along grain boundaries. A novel feature of this particular phenomenon was that in certain cases, especially for twins located in the vicinity of the specimen edge, the etching or preferential electropolishing literally isolated these structures from the matrix.

Site of Lysosome Production During Hepatic Injury

1969 ◽  
Vol 27 ◽  
pp. 348-349
Author(s):  
Nalin J. Unakar
Keyword(s):  
Electron Microscopy ◽  
Golgi Apparatus ◽  
Mouse Liver ◽  
Hepatic Injury ◽  
Close Approximation ◽  
Experimental Conditions ◽  
Toxic Injury

The increased number of lysosomes as well as the close approximation of lysosomes to the Golgi apparatus in tissue under variety of experimental conditions is commonly observed. These observations suggest Golgi involvement in lysosomal production. The role of the Golgi apparatus in the production of lysosomes in mouse liver was studied by electron microscopy of liver following toxic injury by CCI4.

Optimizing conditions for x-ray microchemical analysis in analytical electron microscopy

1978 ◽  
Vol 36 (1) ◽  
pp. 548-549 ◽  
Author(s):  
N. J. Zaluzec
Keyword(s):  
Solid Angle ◽  
Analytical Electron Microscopy ◽  
Incident Beam ◽  
Thin Foil ◽  
Experimental Conditions ◽  
X Ray ◽  
Microchemical Analysis ◽  
Analytical Electron ◽  
Image Position ◽  
Incident Beam Energy

The ultimate sensitivity of microchemical analysis using x-ray emission rests in selecting those experimental conditions which will maximize the measured peak-to-background (P/B) ratio. This paper presents the results of calculations aimed at determining the influence of incident beam energy, detector/specimen geometry and specimen composition on the P/B ratio for ideally thin samples (i.e., the effects of scattering and absorption are considered negligible). As such it is assumed that the complications resulting from system peaks, bremsstrahlung fluorescence, electron tails and specimen contamination have been eliminated and that one needs only to consider the physics of the generation/emission process.The number of characteristic x-ray photons (Ip) emitted from a thin foil of thickness dt into the solid angle dΩ is given by the well-known equation

SEM analysis of the change in the reaction rates with deposit structures in the copper-iron cementation system

1978 ◽  
Vol 36 (1) ◽  
pp. 456-457
Author(s):  
V. Annamalai ◽  
L.E. Murr
Keyword(s):  
Structural Characteristics ◽  
Secondary Electron Emission ◽  
Copper Deposit ◽  
Reaction Rates ◽  
Sem Analysis ◽  
Experimental Conditions ◽  
Major Drawback ◽  
Emission Mode ◽  
Scrap Iron ◽  
Image Position

Economical recovery of copper metal from leach liquors has been carried out by the simple process of cementing copper onto a suitable substrate metal, such as scrap-iron, since the 16th century. The process has, however, a major drawback of consuming more iron than stoichiometrically needed by the reaction.Therefore, many research groups started looking into the process more closely. Though it is accepted that the structural characteristics of the resultant copper deposit cause changes in reaction rates for various experimental conditions, not many systems have been systematically investigated. This paper examines the deposit structures and the kinetic data, and explains the correlations between them.A simple cementation cell along with rotating discs of pure iron (99.9%) were employed in this study to obtain the kinetic results The resultant copper deposits were studied in a Hitachi Perkin-Elmer HHS-2R scanning electron microscope operated at 25kV in the secondary electron emission mode.

Relative Intensities in ED Patterns From Thin Gold Films

1972 ◽  
Vol 30 ◽  
pp. 636-637
Author(s):  
R. H. Morriss ◽  
J. D. C. Peng ◽  
C. D. Melvin
Keyword(s):  
Theoretical Calculations ◽  
Diffraction Theory ◽  
Gold Films ◽  
Reasonable Accuracy ◽  
Experimental Conditions ◽  
Crystal Perfection ◽  
Heavy Atoms ◽  
Fine Focus ◽  
Convergent Beam ◽  
Beam Diffraction

Although dynamical diffraction theory was modified for electrons by Bethe in 1928, relatively few calculations have been carried out because of computational difficulties. Even fewer attempts have been made to correlate experimental data with theoretical calculations. The experimental conditions are indeed stringent - not only is a knowledge of crystal perfection, morphology, and orientation necessary, but other factors such as specimen contamination are important and must be carefully controlled. The experimental method of fine-focus convergent-beam electron diffraction has been successfully applied by Goodman and Lehmpfuhl to single crystals of MgO containing light atoms and more recently by Lynch to single crystalline (111) gold films which contain heavy atoms. In both experiments intensity distributions were calculated using the multislice method of n-beam diffraction theory. In order to obtain reasonable accuracy Lynch found it necessary to include 139 beams in the calculations for gold with all but 43 corresponding to beams out of the [111] zone.

Structure and migration of planar defects in crystals observed in atomic scale

1978 ◽  
Vol 36 (1) ◽  
pp. 284-285 ◽  
Author(s):  
H. Hashimoto ◽  
Y. Sugimoto ◽  
Y. Takai ◽  
H. Endoh
Keyword(s):  
Electron Microscope ◽  
Rotation Angle ◽  
Crystal Surface ◽  
Electron Gun ◽  
Atomic Scale ◽  
Present Observation ◽  
Twist Boundary ◽  
Optical Magnification ◽  
Zinc Crystal ◽  
And Migration

As was demonstrated by the present authors that atomic structure of simple crystal can be photographed by the conventional 100 kV electron microscope adjusted at “aberration free focus (AFF)” condition. In order to operate the microscope at AFF condition effectively, highly stabilized electron beams with small energy spread and small beam divergence are necessary. In the present observation, a 120 kV electron microscope with LaB6 electron gun was used. The most of the images were taken with the direct electron optical magnification of 1.3 million times and then magnified photographically.1. Twist boundary of ZnSFig. 1 is the image of wurtzite single crystal with twist boundary grown on the surface of zinc crystal by the reaction of sulphur vapour of 1540 Torr at 500°C. Crystal surface is parallel to (00.1) plane and electron beam is incident along the axis normal to the crystal surface. In the twist boundary there is a dislocation net work between two perfect crystals with a certain rotation angle.

Control of Autogenous Vein Grafts Prior to Reimplantation, By Electron Microscopy

1972 ◽  
Vol 30 ◽  
pp. 106-107
Author(s):  
John H. L. Watson ◽  
John L. Swedo ◽  
M. Vrandecic
Keyword(s):  
Electron Microscopy ◽  
Light And Electron Microscopy ◽  
Physiological Saline ◽  
Experimental Conditions ◽  
Vein Grafts ◽  
Arterial Blood ◽  
Saphenous Veins ◽  
Autogenous Vein ◽  
Control Of Parameters ◽  
Post Implantation

The ambient temperature and the nature of the storage fluids may well have significant effects upon the post-implantation behavior of venus autografts. A first step in the investigation of such effects is reported here. Experimental conditions have been set which approximate actual operating room procedures. Saphenous veins from dogs have been used as models in the experiments. After removal from the dogs the veins were kept for two hours under four different experimental conditions, viz at either 4°C or 23°C in either physiological saline or whole canine arterial blood. At the end of the two hours they were prepared for light and electron microscopy. Since no obvious changes or damage could be seen in the veins by light microscopy, even with the advantage of tissue specific stains, it was essential that the control of parameters for successful grafts be set by electron microscopy.

A comparative study on the cold type and thermal type field emission guns used in the same electron microscope

1978 ◽  
Vol 36 (1) ◽  
pp. 58-59
Author(s):  
M. Iwatsuki ◽  
Y. Kokubo ◽  
Y. Harada
Keyword(s):  
Electron Microscope ◽  
Field Emission ◽  
Signal To Noise Ratio ◽  
Electron Source ◽  
Resolving Power ◽  
Optical Source ◽  
Experimental Conditions ◽  
High Brightness ◽  
Illumination System ◽  
Transmission Electron

On accout of its high brightness, small optical source size, and minimal energy spread, the field emission gun (FEG) has the advantage that it provides the conventional transmission electron microscope (TEM) with a highly coherent illumination system and directly improves the resolving power and signal-to-noise ratio of the scanning electron microscope (SEM). The FEG is generally classified into two types; the cold field emission (C-FEG) and thermal field emission gun (T-FEG). The former, in which a field emitter is used at the room temperature, was successfully developed as an electron source for the SEM. The latter, in which the emitter is heated to the temperature range of 1000-1800°K, was also proved to be very suited as an electron source for the TEM, as well as for the SEM. Some characteristics of the two types of the FEG have been studied and reported by many authors. However, the results of the respective types have been obtained separately under different experimental conditions.

Structural and functional renal alterations in five-sixth nephrectomized rats on unrestricted diet

1986 ◽  
Vol 44 ◽  
pp. 342-343
Author(s):  
I. Stachura ◽  
M. Pardo ◽  
J. Costello ◽  
D.M. Landwehr
Keyword(s):  
Wistar Rats ◽  
Renal Damage ◽  
Standard Diet ◽  
Experimental Conditions ◽  
Phosphate Intake ◽  
Dietary Restrictions ◽  
Severe Reduction ◽  
Male Wistar Rats ◽  
Unrestricted Diet ◽  
Progressive Renal Insufficiency

Under experimental conditions severe reduction of renal mass results in the hyperfiltration of the remaining nephrons leading to a progressive renal insufficiency. Similar changes are observed in patients with various renal disorders associated with a loss of the functioning nephrons. The progression of renal damage is accelerated by high protein and phosphate intake, and may be modified by the dietary restrictions.We studied 50 five-sixth nephrectarrized male Wistar rats on a standard diet (Rodent Laboratory Chow 5001 Ralston Purina Co., Richmond, Indiana; containing 23.4% protein) over a 20 week period.

Sign in / Sign up

Export Citation Format

Share Document