Reducing Hydrogen Penetration through Corrosion Layer Formed on Zirconium Alloys by Iron Addition

2006 ◽  
Vol 45 ◽  
pp. 1980-1985
Author(s):  
Kazuo Kakiuchi ◽  
Kazutoshi Okubo ◽  
Noboru Itagaki ◽  
Akihiro Miyazaki ◽  
Yoshiaki Ishii ◽  
...  
Keyword(s):  
Hydrogen Absorption ◽  
Electrical Potential ◽  
Potential Gradient ◽  
Zirconium Alloys ◽  
Corrosion Layer ◽  
Potential Measurement ◽  
Irradiation Experiment ◽  
Hydrogen Pickup ◽  
Hydrogen Penetration ◽  
Iron Addition

Latest post-irradiation experiment results of Zry-2 and HiFi alloy (0.4%Fe-Zry2) showed that iron addition reduces the hydrogen pickup by these alloys compared to oxidation amount. In order to clarify the mechanism of reduced hydrogen absorption rate, (1) autoclave test, (2) surface potential measurement and (3) hydrogen absorption test of the intermetallic compound were carried out. Based on these results, a tentative mechanism for hydrogen absorption by zirconium alloys is proposed, taking into account of both the electrical potential gradient over the oxide film as well as the SPP window for hydrogen absorption.

Reducing Hydrogen Penetration through Corrosion Layer Formed on Zirconium Alloys by Iron Addition

2006 ◽  
pp. 1980-1985
Author(s):  
Kazuo Kakiuchi ◽  
Kazutoshi Okubo ◽  
Noboru Itagaki ◽  
Akihiro Miyazaki ◽  
Yoshiaki Ishii ◽  
...  
Keyword(s):  
Zirconium Alloys ◽  
Corrosion Layer ◽  
Hydrogen Penetration ◽  
Iron Addition

Control of hydrogen absorption by nickel films obtained upon magnetic spraying of zirconium alloy using the thermoEMF method

2020 ◽  
Vol 86 (8) ◽  
pp. 32-37
Author(s):  
V. V. Larionov ◽  
Xu Shupeng ◽  
V. N. Kudiyarov
Keyword(s):  
Magnetron Sputtering ◽  
Hydrogen Concentration ◽  
Hydrogen Absorption ◽  
Zirconium Alloy ◽  
Hydrogen Adsorption ◽  
Zirconium Alloys ◽  
Nickel Film ◽  
Protective Film ◽  
Nickel Films ◽  
Hydrogen Penetration

Nickel films formed on the surface of zirconium alloys are often used to protect materials against hydrogen penetration. Hydrogen adsorption on nickel is faster since the latter actively interacts with hydrogen, oxidizes and forms a protective film. The goal of the study is to develop a method providing control of hydrogen absorption by nickel films during vacuum-magnetron sputtering and hydrogenation via measuring thermoEMF. Zirconium alloy E110 was saturated from the gas phase with hydrogen at a temperature of 350°C and a pressure of 2 atm. A specialized Rainbow Spectrum unit was used for coating. It is shown that a nickel film present on the surface significantly affects the hydrogen penetration into the alloy. A coating with a thickness of more than 2 μm deposited by magnetron sputtering on the surface of a zirconium alloy with 1% Nb, almost completely protects the alloy against hydrogen penetration. The magnitude of thermoemf depends on the hydrogen concentration in the zirconium alloy and film thickness. An analysis of the hysteresis width of the thermoEMF temperature loop and a method for determining the effective activation energy of the conductivity of a hydrogenated material coated with a nickel film are presented. The results of the study can be used in assessing the hydrogen concentration and, hence, corrosion protection of the material.

Hydrogen Pickup During Aqueous Corrosion Of Zirconium Alloys

CORROSION ◽  
1961 ◽  
Vol 17 (3) ◽  
pp. 109t-117t ◽  
Author(s):  
WARREN E. BERRY ◽  
DALE A. VAUGHAN ◽  
EARL L. WHITE
Keyword(s):  
Zirconium Alloys ◽  
Aqueous Corrosion ◽  
Hydrogen Pickup

Hydrogen Pickup Mechanism in Zirconium Alloys

2018 ◽  
pp. 312-349
Author(s):  
Adrien Couet ◽  
Arthur T. Motta ◽  
Antoine Ambard ◽  
Robert J. Comstock
Keyword(s):  
Zirconium Alloys ◽  
Hydrogen Pickup

A method of determining electrical potential gradient across mitochondrial membrane in perfused rat hearts

1993 ◽  
Vol 265 (2) ◽  
pp. H445-H452 ◽  
Author(s):  
B. Wan ◽  
C. Doumen ◽  
J. Duszynski ◽  
G. Salama ◽  
K. F. LaNoue
Keyword(s):  
Mitochondrial Membrane ◽  
Electrical Potential ◽  
Potential Gradient ◽  
Order Rate Constant ◽  
Isolated Rat Heart ◽  
First Order ◽  
Order Rate ◽  
Rat Hearts ◽  
Perfused Rat Hearts ◽  
Electrical Potential Gradient

The electrical potential gradient across the mitochondrial membrane (delta psi m) in perfused rat hearts was estimated by calculating the equilibrium distribution of the lipophilic cation tetraphenylphosphonium (TPP+), using measured kinetic constants of uptake and release of TPP+. First-order rate constants of TPP+ uptake were measured during 30-min perfusions of intact rat hearts with tracer amounts (5.0 nM) of tritium-labeled TPP+ ([3H]TPP+) in the perfusate. This was followed by a 30-min washout, during which the first-order rate constant of efflux was estimated. Values of [3H]TPP+ outside the heart and total [3H]TPP+ inside the heart at equilibrium were calculated. From this information and separately estimated time-averaged plasma membrane potentials (delta psi c) it was possible to calculate free cytosolic [3H]TPP+ at equilibrium. It was also possible to calculate free intramitochondrial [3H]TPP+ at equilibrium as the difference between total tissue [3H]TPP+ minus free cytosolic TPP+ and the sum of all the bound [3H]TPP+. Bound [3H]TPP+ was determined from [3H]TPP+ binding constants measured in separate experiments, using both isolated mitochondria and isolated cardiac myocytes under conditions where both delta psi m and delta psi c were zero. Delta psi m was calculated from the intramitochondrial and cytosolic free TPP+ concentrations using the Nernst equation. Values of delta psi m were 144.9 +/- 2.0 mV in hearts perfused with 5 mM pyruvate and 118.2 +/- 1.4 mV in hearts perfused with 11 mM glucose, in good agreement with delta psi m obtained from isolated rat heart mitochondria.(ABSTRACT TRUNCATED AT 250 WORDS)

scholarly journals Hydride Rim Formation in E110 Zirconium Alloy during Gas-Phase Hydrogenation

Metals ◽  
2020 ◽  
Vol 10 (2) ◽  
pp. 247
Author(s):  
Viktor Kudiiarov ◽  
Ivan Sakvin ◽  
Maxim Syrtanov ◽  
Inga Slesarenko ◽  
Andrey Lider
Keyword(s):  
Mechanical Properties ◽  
Gas Phase ◽  
Zirconium Alloy ◽  
Zirconium Alloys ◽  
Subsequent Formation ◽  
Delayed Hydride Cracking ◽  
Hydrogen Penetration ◽  
Significant Change ◽  
Hydride Cracking

The work is devoted to the study of the laws of the formation of a hydride rim in E110 zirconium alloy claddings during gas-phase hydrogenation. The problem of hydrogen penetration and accumulation and the subsequent formation of hydrides in the volume of zirconium cladding tubes of water-cooled power reactors remain relevant. The formation of brittle hydrides in a zirconium matrix firstly, leads to a significant change in the mechanical properties, and secondly, can cause the destruction of the claddings by the mechanism of delayed hydride cracking. The degree of the hydride’s effect on the mechanical properties of zirconium cladding is mainly determined by the features of the hydride’s distribution and orientation. The problem of hydride rim formation in zirconium alloys with niobium is quite new and poorly studied. Therefore, the study of hydride rim formation in Russian zirconium alloy is important and necessary for predicting the behavior of claddings during the formation of the hydride rim.

Electrophysiology of renal capillary membranes: gel concept applied and Starling model challenged

1988 ◽  
Vol 254 (3) ◽  
pp. F364-F373 ◽  
Author(s):  
M. Wolgast ◽  
G. Ojteg
Keyword(s):  
Charge Density ◽  
Electrical Potential ◽  
Potential Gradient ◽  
Swelling Pressure ◽  
Porous Membrane ◽  
Fixed Charge ◽  
Fixed Charge Density ◽  
Capillary Membranes ◽  
External Forces ◽  
Gel Membranes

In the classical Starling model the hydrostatic pressure in the pores is generally lower than that in capillary plasma, a phenomenon that necessitates the assumption of a rigid porous membrane. In flexible gel membranes, the capillary pressure is suggested to be balanced by a gel swelling pressure generated by negative fixed charges. Regarding the fluid transfer, the transmembranous electrical potential gradient will generate a net driving electroosmotic force. This force will be numerically similar to the net driving Starling force in small pores, but distinctly different in large pores. From previous data on the hydrostatic and colloid osmotic forces, the fixed charge density at the two interfaces of 1) the glomerular and 2) the peritubular capillary membrane were calculated and used to predict the flux of a series of charged protein probes. The close fit to the experimental data in both the capillary beds is in line with the gel concept presented. The gel concept (but hardly a rigid membrane) explains the ability of capillary membranes to alter their permeability in response to external forces. Gel membranes can furthermore be predicted to have a self-rinsing ability, as entrapped proteins will increase the local fixed charge density, leading to fluid entry into the region between the particle and the pore rim, which by consequent widening of the channel will facilitate extrusion of trapped proteins.

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