Tritium-permeation-barrier properties of erbium oxide (TPB) coating on CLAM steel

Abstract Tritium (T) permeation through plasma-facing component (PFC) into the coolant is a major concern of fusion reactor operation. In this work, deuterium (D) permeation through CLAM steel, CLAM/CLAM and CLAM/Fe-Cr-Al samples prepared by hot isostatic pressing (HIP) are tested in a linear plasma device. Only the downstream surfaces of the samples are oxidized with controlled atmosphere to form permeation barrier. No significant effect on D diffusion and penetration can be observed for the joining interfaces, while the dense oxide layer at the downstream side plays an important role in suppressing D permeation. The downstream surface oxidization of CLAM/Fe-Cr-Al is found to effectively reduce D permeation flux by a factor up to 1000.

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Effect of Substrate Surface Oxidation on Tritium Permeation Barrier Properties of MOD Er2O3 Coating

Fusion Science & Technology ◽

10.13182/fst11-1t2 ◽

2011 ◽

Author(s):

Dongxun Zhang

Keyword(s):

Substrate Surface ◽

Surface Oxidation ◽

Barrier Properties ◽

Tritium Permeation

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Investigation of coating CLAM steel substrates with erbium oxide by a magnetron sputtering method

Fusion Engineering and Design ◽

10.1016/j.fusengdes.2010.03.059 ◽

2010 ◽

Vol 85 (7-9) ◽

pp. 1401-1405 ◽

Cited By ~ 8

Author(s):

Shuai Liu ◽

Xin Ju ◽

Yong Xin ◽

Jie Qiu ◽

Tao Li ◽

...

Keyword(s):

Magnetron Sputtering ◽

Erbium Oxide ◽

Clam Steel ◽

Steel Substrates

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Organization of tight junctions in the choroid plexus epithelium

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100082546 ◽

1978 ◽

Vol 36 (2) ◽

pp. 336-337

Author(s):

B. Van Deurs ◽

J. K. Koehler

Keyword(s):

Choroid Plexus ◽

Present Report ◽

Freeze Fracture ◽

Barrier Properties ◽

Cell Junctions ◽

Structural Basis ◽

Apical Surface ◽

Choroid Plexus Epithelium ◽

Solid Nitrogen ◽

Special Composition

The choroid plexus epithelium constitutes a blood-cerebrospinal fluid (CSF) barrier, and is involved in regulation of the special composition of the CSF. The epithelium is provided with an ouabain-sensitive Na/K-pump located at the apical surface, actively pumping ions into the CSF. The choroid plexus epithelium has been described as “leaky” with a low transepithelial resistance, and a passive transepithelial flux following a paracellular route (intercellular spaces and cell junctions) also takes place. The present report describes the structural basis for these “barrier” properties of the choroid plexus epithelium as revealed by freeze fracture.Choroid plexus from the lateral, third and fourth ventricles of rats were used. The tissue was fixed in glutaraldehyde and stored in 30% glycerol. Freezing was performed either in liquid nitrogen-cooled Freon 22, or directly in a mixture of liquid and solid nitrogen prepared in a special vacuum chamber. The latter method was always used, and considered necessary, when preparations of complementary (double) replicas were made.

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Growth of near noble metal Pd and Pt thin film silicides morphology and structure

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100112464 ◽

1984 ◽

Vol 42 ◽

pp. 498-499

Author(s):

E. I. Alessandrini ◽

M. O. Aboelfotoh

Keyword(s):

Noble Metals ◽

Annealing Temperature ◽

Chemical Compounds ◽

Barrier Properties ◽

Solid State Reactions ◽

Transmission Electron ◽

Stable Chemical ◽

Metal Thickness ◽

Amorphous Si ◽

Si Films

Considerable interest has been generated in solid state reactions between thin films of near noble metals and silicon. These metals deposited on Si form numerous stable chemical compounds at low temperatures and have found applications as Schottky barrier contacts to silicon in VLSI devices. Since the very first phase that nucleates in contact with Si determines the barrier properties, the purpose of our study was to investigate the silicide formation of the near noble metals, Pd and Pt, at very thin thickness of the metal films on amorphous silicon.Films of Pd and Pt in the thickness range of 0.5nm to 20nm were made by room temperature evaporation on 40nm thick amorphous Si films, which were first deposited on 30nm thick amorphous Si3N4 membranes in a window configuration. The deposition rate was 0.1 to 0.5nm/sec and the pressure during deposition was 3 x 10 -7 Torr. The samples were annealed at temperatures in the range from 200° to 650°C in a furnace with helium purified by hot (950°C) Ti particles. Transmission electron microscopy and diffraction techniques were used to evaluate changes in structure and morphology of the phases formed as a function of metal thickness and annealing temperature.

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