A Study on Correlation of Low Voltage Cathodoluminescent Properties with Electrical Conductivity of In[sub 2]O[sub 3]-Coated ZnGa[sub 2]O[sub 4]:Mn Phosphors

2000 ◽  
Vol 147 (9) ◽  
pp. 3559 ◽  
Author(s):  
Jin Young Kim ◽  
Duk Young Jeon ◽  
Il Yu ◽  
Hong-Gun Yang
2019 ◽  
Vol 7 (2) ◽  
pp. 17-21
Author(s):  
M. Purushothaman ◽  
◽  
K. Natarajan

Concrete is regarded as a composite material that has good mechanical and durability properties for construction. However normal concrete is poor in electrical conductivity. An endeavour has been made with concrete to have all these three properties. The addition of small amounts of short carbon fibers and a nanomaterial silica fume to the concrete mixture causes an increase in strength and durability properties as well as electrical conductivity. In this paper, experimental results of compressive strength and electrical resistivity are presented. This Concrete technology can be applied with low voltage current for de-icing on highways and airfields, during snowfall in the winter season. This technique will help to reduce the cost and environmental issues of roads in snow fall region.


2012 ◽  
Vol 40 (4) ◽  
pp. 972-979
Author(s):  
Robert Rhodes ◽  
Trevor Moeller ◽  
Dennis Keefer

2021 ◽  
Vol 11 (16) ◽  
pp. 7534
Author(s):  
Alejandro Cortés ◽  
Alberto Jiménez-Suárez ◽  
Mónica Campo ◽  
Alejandro Ureña ◽  
Silvia G. Prolongo

This work consists of the development of an easy strategy to transform any structure into an efficient surface heater by the application of a low voltage over 3D printed nanocomposite circuits. To this end, the electrical conductivity and self-heating capabilities of UV-Assisted Direct Write 3D printed circuits doped with carbon nanotubes were widely explored as a function of the number of printed layers. Moreover, an optimization of the printing process was carried out by comparing the accuracy and printability obtained when printing with two different configurations: extruding and curing the ink in the same stage or curing the extruded ink in a second stage, after the whole layer was deposited. In this regard, the great homogeneity and repeatability of the heating showed by the four-layer printed circuits, together with their excellent performance for long heating times, proved their applicability to convert any structure to a surface heater. Finally, the deicing capability of the four-layer circuit was demonstrated, being able to remove a 2.5 mm thick ice layer in 4 min and 4 s.


2014 ◽  
Vol 617 ◽  
pp. 72-77 ◽  
Author(s):  
Kazuyuki Kakegawa ◽  
Chun Ming Wen ◽  
Naofumi Uekawa ◽  
Takashi Kojima

Possibility of a use of SiC as SPS die was examined. Although SiC has good strength even at high temperature, electrical conductivity is too low as the SPS die. Maximum output voltage of typical SPS machine is 10 V. Joule heat of SiC by application of 10 V is too small to increase its temperature. One idea to solve this problem in this study is to apply higher voltage to the SiC die. Using prototype high voltage SPS equipment, the temperature of SiC die was successfully elevated. Another idea is to heat the SiC die in advance. SiC has a semiconducting behavior, so that the electrical conductivity at high temperature becomes sufficient for the ordinary SPS equipment. Using SPS machine which has hot-wall, heaters surrounding the die, the temperature of the SiC die was successfully increased by application of low voltage. This SPS had similar sintering effects as the ordinary ones. Partly transparent alumina was successfully prepared. Initial compositional fluctuation of Pb (Zr,Ti)O3was maintained after it was densified by this SiC-SPS.


Author(s):  
Marek Malecki ◽  
J. Victor Small ◽  
James Pawley

The relative roles of adhesion and locomotion in malignancy have yet to be clearly established. In a tumor, subpopulations of cells may be recognized according to their capacity to invade neighbouring tissue,or to enter the blood stream and metastasize. The mechanisms of adhesion and locomotion are themselves tightly linked to the cytoskeletal apparatus and cell surface topology, including expression of integrin receptors. In our studies on melanomas with Fluorescent Microscopy (FM) and Cell Sorter(FACS), we noticed that cells in cultures derived from metastases had more numerous actin bundles, then cells from primary foci. Following this track, we attempted to develop technology allowing to compare ultrastructure of these cells using correlative Transmission Electron Microscopy(TEM) and Low Voltage Scanning Electron Microscopy(LVSEM).


Author(s):  
Marek Malecki ◽  
James Pawley ◽  
Hans Ris

The ultrastructure of cells suspended in physiological fluids or cell culture media can only be studied if the living processes are stopped while the cells remain in suspension. Attachment of living cells to carrier surfaces to facilitate further processing for electron microscopy produces a rapid reorganization of cell structure eradicating most traces of the structures present when the cells were in suspension. The structure of cells in suspension can be immobilized by either chemical fixation or, much faster, by rapid freezing (cryo-immobilization). The fixation speed is particularly important in studies of cell surface reorganization over time. High pressure freezing provides conditions where specimens up to 500μm thick can be frozen in milliseconds without ice crystal damage. This volume is sufficient for cells to remain in suspension until frozen. However, special procedures are needed to assure that the unattached cells are not lost during subsequent processing for LVSEM or HVEM using freeze-substitution or freeze drying. We recently developed such a procedure.


Author(s):  
John C. Russ ◽  
Nicholas C. Barbi

The rapid growth of interest in attaching energy-dispersive x-ray analysis systems to transmission electron microscopes has centered largely on microanalysis of biological specimens. These are frequently either embedded in plastic or supported by an organic film, which is of great importance as regards stability under the beam since it provides thermal and electrical conductivity from the specimen to the grid.Unfortunately, the supporting medium also produces continuum x-radiation or Bremsstrahlung, which is added to the x-ray spectrum from the sample. It is not difficult to separate the characteristic peaks from the elements in the specimen from the total continuum background, but sometimes it is also necessary to separate the continuum due to the sample from that due to the support. For instance, it is possible to compute relative elemental concentrations in the sample, without standards, based on the relative net characteristic elemental intensities without regard to background; but to calculate absolute concentration, it is necessary to use the background signal itself as a measure of the total excited specimen mass.


Author(s):  
Klaus-Ruediger Peters ◽  
Samuel A. Green

High magnification imaging of macromolecules on metal coated biological specimens is limited only by wet preparation procedures since recently obtained instrumental resolution allows visualization of topographic structures as smal l as 1-2 nm. Details of such dimensions may be visualized if continuous metal films with a thickness of 2 nm or less are applied. Such thin films give sufficient contrast in TEM as well as in SEM (SE-I image mode). The requisite increase in electrical conductivity for SEM of biological specimens is achieved through the use of ligand mediated wet osmiuum impregnation of the specimen before critical point (CP) drying. A commonly used ligand is thiocarbohvdrazide (TCH), first introduced to TEM for en block staining of lipids and glvcomacromolecules with osmium black. Now TCH is also used for SEM. However, after ligand mediated osinification nonspecific osmium black precipitates were often found obscuring surface details with large diffuse aggregates or with dense particular deposits, 2-20 nm in size. Thus, only low magnification work was considered possible after TCH appl ication.


Author(s):  
T. Miyokawa ◽  
S. Norioka ◽  
S. Goto

Field emission SEMs (FE-SEMs) are becoming popular due to their high resolution needs. In the field of semiconductor product, it is demanded to use the low accelerating voltage FE-SEM to avoid the electron irradiation damage and the electron charging up on samples. However the accelerating voltage of usual SEM with FE-gun is limited until 1 kV, which is not enough small for the present demands, because the virtual source goes far from the tip in lower accelerating voltages. This virtual source position depends on the shape of the electrostatic lens. So, we investigated several types of electrostatic lenses to be applicable to the lower accelerating voltage. In the result, it is found a field emission gun with a conical anode is effectively applied for a wide range of low accelerating voltages.A field emission gun usually consists of a field emission tip (cold cathode) and the Butler type electrostatic lens.


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