Analysis of the Corrosion Products Formed on Ti and a Ti-Pd Alloy During Exposure in Hot Water

1981 ◽  
Vol 11 ◽  
Author(s):  
Ingemar Olefjord ◽  
HÅkan Mattsson
Keyword(s):  
Surface Analysis ◽  
Room Temperature ◽  
Aqueous Media ◽  
Chloride Ions ◽  
Hot Water ◽  
Short Exposure ◽  
Reaction Products ◽  
Pd Alloy ◽  
Temperature Exposure ◽  
Water Saturated

ABSTRACTThis is a preliminary report dealing with the surface analysis of reaction products formed on Ti and a Ti-Pd alloy during their exposure in hot water. The compositions of the aqueous media were varied with respect to the dissolved oxygen and the content of chloride ions. The temperature was 60°C and the exposure times were 10 min. and 6 months. Work is in progress in which samples are exposed at 80°C and 95°C in the aqueous solutions. Surface analysis was also performed on a sample which had been exposed in water-saturated bentonite.It appears from the ESCA spectra that the oxide products formed on the surface consist of TiO The results also indicate that the thickness of the film formed at 60°C in water is in the range 50 Å to 100 Å. This is somewhat more than that obtained after exposure in water at room temperature. Exposure for 6 months increases the thickness of the oxide two to three times compared to that obtained during the short exposure at 60°C. The analyses of the samples that had been embedded in bentonite indicate that the surface reaction products are thinner than those found on the surface after exposure in an open vessel.

scholarly journals Effect of Zr Addition on Overaging and Tensile Behavior of 2618 Aluminum Alloy

Metals ◽  
2019 ◽  
Vol 9 (2) ◽  
pp. 130 ◽  
Author(s):  
Stefania Toschi ◽  
Eleonora Balducci ◽  
Lorella Ceschini ◽  
Eva Mørtsell ◽  
Alessandro Morri ◽  
...  
Keyword(s):  
Electron Microscopy ◽  
Room Temperature ◽  
Base Alloy ◽  
Heat Treatment Condition ◽  
Tensile Behavior ◽  
Hot Water ◽  
Overaged Condition ◽  
Zr Addition ◽  
Precipitate Microstructure ◽  
Temperature Exposure

The effect of Zr addition on overaging and tensile behavior in a 2618 Al–Cu–Mg–Ni–Fe alloy has been investigated in this study. The chemical composition of the base 2618 alloy, containing ~0.1 wt % of Zr, was modified by adding Zr to reach the target content of 0.25 wt %. Cast bars were T6 heat-treated according to industrial parameters, involving soaking at 525 °C for 8 h, quenching in hot water (50 °C), and artificial aging at 200 °C for 20 h. Both the T6 2618 and 2618 + Zr alloys were overaged at 250 and 300 °C for up to 192 h, to evaluate the decrease in hardness with high temperature exposure time. The tensile behavior of the alloys was investigated in the overaged condition, both at room temperature and at 250 °C. The microstructure of the as-cast and solution-treated samples was investigated by optical and scanning electron microscopy, while the precipitate microstructure at the nanoscale was analyzed by transmission electron microscopy in overaged condition. Experimental data revealed that the presence of 0.25 wt % Zr does not induce modifications at the macroscale on the microstructure of 2618 alloy while, at the nanoscale, the presence of Zr-based precipitates was observed. The overaged Zr-enriched alloy showed increased yield and ultimate tensile strength in comparison to the base alloy, at equal heat treatment condition, both at room temperature and 250 °C.

Au–Pd bimetallic nanoparticles supported on a high nitrogen-rich ordered mesoporous carbon as an efficient catalyst for room temperature Ullmann coupling of aryl chlorides in aqueous media

2018 ◽  
Vol 54 (52) ◽  
pp. 7155-7158 ◽  
Author(s):  
Babak Karimi ◽  
Hossein Barzegar ◽  
Hojatollah Vali
Keyword(s):  
Mesoporous Carbon ◽  
Room Temperature ◽  
Bimetallic Nanoparticles ◽  
Aqueous Media ◽  
Coupling Reaction ◽  
Efficient Catalyst ◽  
Aryl Chlorides ◽  
Ordered Mesoporous ◽  
Pd Alloy ◽  
Ullmann Coupling

An ionic liquid derived highly nitrogen-rich mesoporous carbon supported Au–Pd alloy was found to be an efficient and recyclable catalyst for the Ullmann coupling reaction of various aryl chlorides at room temperature.

ESCA Investigation of the Reaction Products Formed on Titanium Exposed to Water Saturated Bentonite Clay

1985 ◽  
Vol 50 ◽  
Author(s):  
Håkan Mattsson ◽  
Ingemar Olefjord
Keyword(s):  
Spent Nuclear Fuel ◽  
Bentonite Clay ◽  
Oxide Thickness ◽  
Oxide Growth ◽  
Main Constituent ◽  
Reaction Products ◽  
Metal Interface ◽  
Pd Alloy ◽  
Logarithmic Law ◽  
Water Saturated

AbstractTitanium is one of the materials proposed in the Swedish programme for the final containment of spent nuclear fuel. In the present investigation, the final repository environment was simulated on the laboratory scale by embedding titanium and a Ti-Pd alloy in dense, water-saturated bentonite clay. The temperature was 95°C and the exposures lasted between 4 months and 2 years. Analysis was performed using ESCA combined with ion etching.The reaction products formed on the surface consists of TiO2 Montmorillonite - the main constituent of bentonite - is incorporated in the oxide. Suboxides exist near the oxide/metal interface.The oxide thickness is in the range 70–100 Å. The oxide growth between 4 months and 2 years is small. No significant influence of Pd could be noted. If it is assumed, that the oxide growth follows a logarithmic law, the expression giving the thickest oxide is y = 5.5 In t (where y is the oxide thickness (Å) and t is the exposure time (s)).

Temperature Dependence of the Self-Assembled Styrene Based Random Ionomers in Aqueous Solution

2003 ◽  
Vol 775 ◽  
Author(s):  
Sung-Hwa Oh ◽  
Ju-Myung Song ◽  
Joon-Seop Kim ◽  
Hyang-Rim Oh ◽  
Jeong-A Yu
Keyword(s):  
Partition Coefficients ◽  
Room Temperature ◽  
Aqueous Media ◽  
The Self ◽  
Spectroscopic Methods ◽  
Ion Content ◽  
Repeat Units ◽  
Notable Effect ◽  
Order Of Magnitude ◽  
Experimental Errors

AbstractSolution behaviors of poly(styrene-co-sodium methacrylate) were studied by fluorescence spectroscopic methods using pyrene as a probe. The mol% of methacrylate was in the range 3.6–9.4. Water and N,N-dimethylforamide(DMF) mixture was used as a solvent (DMF/water = 0.2 mol %). The critical micelle (or aggregation) concentrations of ionomers and the partition coefficients of pyrene were obtained the temperature range 10–80°C. At room temperature, the values of CMCs (or CACs) were in the range 4.7 ×10-6 5.3 ×10-6 g/mL and we could not find any notable effect of the content of ionic repeat units within the experimental errors. Unlike CMCs, as the ion content increased, partitioning of pyrene between the hydrophobic aggregates and an aqueous media decreased from 1.5 ×105 to 9.4 ×104. As the temperature increased from 10 to 80 °C, the values of CMCs increased less than one order of magnitude. While, the partition coefficients of pyrene decreased one order of magnitude and the effect of the ion content became negligible.

The Influence of Palladium Addition on the Texture Transition in Silver

2005 ◽  
Vol 495-497 ◽  
pp. 1461-1466
Author(s):  
Kazuyoshi Sekine ◽  
Zheng Rong Zhang
Keyword(s):  
Recrystallization Texture ◽  
Room Temperature ◽  
Stable State ◽  
Rolling Texture ◽  
Transition Process ◽  
Superconducting Tapes ◽  
Alloying Element ◽  
Metallic Substrates ◽  
Pd Alloy ◽  
Texture Transition

Texture transition in silver introduced by the addition of 10 at% Pd alloying element was analyzed in this study. Experimental results show that the dependence of rolling texture on rolling reduction in thickness rather than on rolling temperature has been mostly detected, and the recrystallization texture transition process in pure silver is so strongly influenced by the addition of alloying element palladium that the final stable state of recrystallization texture has been changed from Brass {011}<211> orientation to Copper {112}<111> orientation. The single cube {001}<100> recrystallization texture in warm rolled silver, Brass {011}<211> recrystallization texture in room-temperature rolled silver, and Copper {112}<111> recrystallization texture in room-temperature rolled or warm rolled Ag-10 at% Pd alloy have been successfully developed for the fabrication of metallic substrates suitable for high-temperature superconducting tapes.

A Ag–Pd alloy supported on an amine-functionalized UiO-66 as an efficient synergetic catalyst for the dehydrogenation of formic acid at room temperature

2016 ◽  
Vol 6 (3) ◽  
pp. 869-874 ◽  
Author(s):  
Shu-Tao Gao ◽  
Weihua Liu ◽  
Cheng Feng ◽  
Ning-Zhao Shang ◽  
Chun Wang
Keyword(s):  
Catalytic Activity ◽  
Formic Acid ◽  
Room Temperature ◽  
High Catalytic Activity ◽  
Amine Functionalized ◽  
Pd Alloy

Ag–Pd alloys deposited on an amine-functionalized UiO-66(NH2–UiO-66) have been successfully prepared via a pre-coordination method and used as a AgPd@NH2–UiO-66 catalyst with 100% H2 selectivity and a high catalytic activity.

On the Chemistry of Tetrabenzyl Thiuram Disulfide and Tetramethyl Thiuram Disulfide with Bis (Triethoxysilylpropyl) Tetrasulfide in Silica Compounds

2003 ◽  
Vol 76 (4) ◽  
pp. 876-891 ◽  
Author(s):  
R. N. Datta ◽  
A. G. Talma ◽  
S. Datta ◽  
P. G. J. Nieuwenhuis ◽  
W. J. Nijenhuis ◽  
...  
Keyword(s):  
High Performance ◽  
Room Temperature ◽  
Succinic Anhydride ◽  
Dynamic Properties ◽  
The Other ◽  
Resonance Spectroscopy ◽  
Reaction Products ◽  
Negative Effect ◽  
Higher Temperature ◽  
Analytical Tools

Abstract The use of thiurams such as Tetramethyl thiuram disulfide (TMTD) or Tetrabenzyl thiuram disulfide (TBzTD) has been explored to achieve higher cure efficiency. The studies suggest that a clear difference exists between the effect of TMTD versus TBzTD. TMTD reacts with Bis (triethoxysilylpropyl) tetrasulfide (TESPT) and this reaction can take place even at room temperature. On the other hand, the reaction of TBzTD with TESPT is slow and takes place only at higher temperature. High Performance Liquid Chromatography (HPLC) with mass (MS) detection, Nuclear Magnetic Resonance Spectroscopy (NMR) and other analytical tools have been used to understand the differences between the reaction of TMTD and TESPT versus TBzTD and TESPT. The reaction products originating from these reactions are also identified. These studies indicate that unlike TMTD, TBzTD improves the cure efficiency allowing faster cure without significant effect on processing characteristics as well as dynamic properties. The loading of TESPT is reduced in a typical Green tire compound and the negative effect on viscosity is repaired by addition of anhydrides, such as succinic anhydride, maleic anhydride, etc.

Uranyl Complexation by Chloride Ions. Formation of a Tetrachlorouranium(VI) Complex in Room Temperature Ionic Liquids [Bmim][Tf2N] and [MeBu3N][Tf2N]

2006 ◽  
Vol 45 (26) ◽  
pp. 10419-10421 ◽  
Author(s):  
M.-O. Sornein ◽  
C. Cannes ◽  
C. Le Naour ◽  
G. Lagarde ◽  
E. Simoni ◽  
...  
Keyword(s):  
Ionic Liquids ◽  
Room Temperature ◽  
Chloride Ions ◽  
Room Temperature Ionic Liquids
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