EXAFS and XANES spectroscopy study of the oxidation and deprotonation of biotite

1989 ◽  
Vol 53 (373) ◽  
pp. 591-602 ◽  
Author(s):  
Bernd Güttler ◽  
Wilhelm Niemann ◽  
Simon A. T. Redfern
Keyword(s):  
Annealing Temperature ◽  
Annealing Process ◽  
Xanes Spectroscopy ◽  
Nearest Neighbour ◽  
Structural Topology ◽  
Spectroscopy Study ◽  
Correlation Peak ◽  
Coordination Numbers ◽  
Thermally Activated ◽  
Significant Process

AbstractThe coupled thermal oxidation and deprotonation in air of iron-rich biotite (FeO + Fe2O3 = 34%) has been investigated by EXAFS and XANES spectroscopy at the Fe-K edge and by XANES spectroscopy at the Ti-K edge. Samples annealed for 5 h at temperatures between 250° to 600°C have been studied. Distortions mainly of the Fe-Fe correlation within the octahedral layers are reflected in increasing Debye-Waller factors of the Fe-Fe correlation peak proportional to the annealing temperature. Unchanged Fe-O nearest-neighbour and Fe-Fe next-nearest-neighbour coordination numbers show that these distortions, nonetheless, do not change the structural topology of the octahedral layers. A model is introduced to demonstrate that increasing distortions are compatible with the expected heterogenous deprotonation mechanism in biotite. Titanium occurs in octahedral coordination. It was found to be unaffected by the coupled oxidation/deprotonation process. Both the coordination number and the valence state stay constant during the annealing process, in spite of dramatic changes of the Fe2+/Fe3+ ratio. Thermally activated hopping conduction involving Ti according to Fe2+Ti4+ → Fe3+Ti3+ is, therefore, not a significant process during thermal deprotonation and oxidation in biotite.

Structural Changes of UHV Deposited Titanium Thin Films in Presence of Oxygen Flow and Temperature

2011 ◽  
Vol 110-116 ◽  
pp. 1094-1098
Author(s):  
Haleh Kangarlou ◽  
Mehdi Bahrami Gharahasanloo ◽  
Akbar Abdi Saray ◽  
Reza Mohammadi Gharabagh
Keyword(s):  
Room Temperature ◽  
Structural Changes ◽  
Annealing Temperature ◽  
Annealing Process ◽  
Oxygen Flow ◽  
Glass Substrates ◽  
Annealing Temperatures ◽  
Titanium Thin Films ◽  
Deposition Angle ◽  
Ti Films

Ti films of same thickness, and near normal deposition angle, and same deposition rate were deposited on glass substrates, at room temperature, under UHV conditions. Different annealing temperatures as 393K, 493K and 593K with uniform 8 cm3/sec, oxygen flow, were used for producing titanium oxide layers. Their nanostructures were determined by AFM and XRD methods. Roughness of the films changed due to annealing process. The gettering property of Ti and annealing temperature can play an important role in the nanostructure of the films.

Raman Spectra of Ion Implanted Graphite

1981 ◽  
Vol 7 ◽  
Author(s):  
B.S. Elman ◽  
H. Mazurek ◽  
M.S. Dresselhaus ◽  
G. Dresselhaus
Keyword(s):  
Raman Spectroscopy ◽  
Ion Implantation ◽  
Raman Spectra ◽  
Annealing Temperature ◽  
Annealing Process ◽  
Lattice Order ◽  
Annealing Temperatures ◽  
High Fluences ◽  
Lattice Damage ◽  
The Way

ABSTRACTRaman spectroscopy is used in a variety of ways to monitor different aspects of the lattice damage caused by ion implantation into graphite. Particular attention is given to the use of Raman spectroscopy to monitor the restoration of lattice order by the annealing process, which depends critically on the annealing temperature and on the extent of the original lattice damage. At low fluences the highly disordered region is localized in the implanted region and relatively low annealing temperatures are required, compared with the implantation at high fluences where the highly disordered region extends all the way to the surface. At high fluences, annealing temperatures comparable to those required for the graphitization of carbons are necessary to fully restore lattice order.

Effect of Homogenization Annealing on Wear Properties of Thixo-Extrued Copper Alloy

2022 ◽  
Vol 327 ◽  
pp. 71-81
Author(s):  
Yun Xin Cui ◽  
Han Xiao ◽  
Chi Xiong ◽  
Rong Feng Zhou ◽  
Zu Lai Li ◽  
...  
Keyword(s):  
Friction Factor ◽  
Annealing Time ◽  
Copper Alloy ◽  
Loss Rate ◽  
Annealing Temperature ◽  
Brinell Hardness ◽  
Annealing Process ◽  
Wear Properties ◽  
Wear Performance ◽  
Semi Solid

The semi-solid extruded CuSn10P1 alloy bushings were homogenization annealed. The effects of annealing process on the hardness and wear properties of bushings were researched. The results show the Brinell hardness increases firstly and then decreases with the increase of annealing temperature and annealing time. With the annealing temperature increasing, the grinding loss rate and friction factor decrease firstly and then increase. At the annealing time of 120 min, the grinding loss rate decreases from 7% at the annealing temperature of 450 °C to 6% at 500 °C, and then increases from 6% at 500 °C to 12% at 600 °C. The friction factor decreases from 0.54 to 0.48 and then increases to 0.83. At the annealing temperature of 500 °C, the grinding loss rate decreases from 11% at the annealing time of 60 min to 6% at 120 min, and then increases to 15% at 150 min. The friction factor decreases from 0.67 to 0.48 and then increases to 0.72. The best wear performance and Brinell hardness can be obtained at annealing temperature of 500 °C for 120 min.

scholarly journals Effect of Annealing Process on the Mechanical Properties of X70 Pipeline Steel

2018 ◽  
Vol 186 ◽  
pp. 02001
Author(s):  
Teng-wei Zhu ◽  
Cheng-liang Miao ◽  
Zheng Cheng ◽  
Zhipeng Wang ◽  
Yang Cui ◽  
...  
Keyword(s):  
Electron Microscopy ◽  
Mechanical Properties ◽  
Scanning Electron Microscopy ◽  
Tensile Strength ◽  
Annealing Temperature ◽  
Pipeline Steel ◽  
Annealing Process ◽  
X70 Pipeline Steel ◽  
Grain Sizes ◽  
Scanning Electron

The influence of the mechanical properties of X70 pipeline steel under different annealing temperature was studied. The corresponding microstructure was investigated by the Field Emission Scanning Electron Microscopy. The results showed that the yield strength and the tensile strength both experienced from rise to decline with the increase of annealing temperature. The grain sizes were coarse and a large amount of cementite precipitated due to preserving temperature above 550 °, which induced matrix fragmentation and deteriorate the -10 ° DWTT Toughness. There were little changes on the microstructure and mechanical properties when the annealing temperature was under 500 °.

scholarly journals Thermal Stability, Hardness, and Corrosion Behavior of the Nickel–Ruthenium–Phosphorus Sputtering Coatings

Coatings ◽  
2020 ◽  
Vol 10 (8) ◽  
pp. 786
Author(s):  
Yu-Cheng Hsiao ◽  
Fan-Bean Wu
Keyword(s):  
Pitting Corrosion ◽  
Annealing Temperature ◽  
Surface Hardness ◽  
Input Power ◽  
Annealing Process ◽  
Nacl Solution ◽  
Annealing Temperatures ◽  
Heat Treated ◽  
Composition Variation ◽  
Heat Treated Temperature

Nickel–ruthenium–phosphorus, Ni–Ru–P, alloy coatings were fabricated by magnetron dual-gun co-sputtering from Ni–P alloy and Ru source targets. The composition variation and related microstructure evolution of the coatings were manipulated by the input power modulation. The as-prepared Ni–Ru–P alloy coatings with a Ru content less than 12.2 at.% are amorphous/nanocrystalline, while that with a high Ru content of 52.7 at.% shows a feature of crystallized Ni, Ru, and Ru2P mixed phases in the as-deposited state. The crystallized phases for high Ru content Ni–Ru–P coatings are stable against annealing process up to 600 °C. By contrast, the amorphous/nanocrystalline Ni–Ru–P thin films withstand a heat-treated temperature up to 475 °C and then transform into Ni(Ru) and NixPy crystallized phases at an annealing temperature over 500 °C. The surface hardness of the Ni–Ru–P films ranges from 7.2 to 12.1 GPa and increases with the Ru content and the annealing temperatures. A highest surface hardness is found for the 550 °C annealed Ni–Ru–P with a high Ru content of 52.7 at.%. The Ecorr values of the heat-treated amorphous/nanocrystalline Ni–Ru–P coatings become more negative, while with a high Ru content over 27.3 at.% the Ni–Ru–P films show more negative Ecorr values after annealing process. The pitting corrosion feature is observed for the amorphous/nanocrystalline Ni–Ru–P coatings when tested in a 3.5M NaCl solution. Severer pitting corrosion is found for the 550 °C annealed Ni–Ru–P coatings. The development of Ni(Ru) and NixPy crystallized phases during annealing is responsible for the degeneration of corrosion resistance.

scholarly journals Effect of Annealing on the Interface and Mechanical Properties of Cu-Al-Cu Laminated Composite Prepared with Cold Rolling

Materials ◽  
2020 ◽  
Vol 13 (2) ◽  
pp. 369
Author(s):  
Xing Fu ◽  
Rui Wang ◽  
Qingfeng Zhu ◽  
Ping Wang ◽  
Yubo Zuo
Keyword(s):  
Mechanical Properties ◽  
Annealing Temperature ◽  
Laminated Composite ◽  
Phase Evolution ◽  
Annealing Process ◽  
High Annealing Temperature ◽  
Roll Bonding ◽  
Cold Roll ◽  
High Annealing ◽  
Cold Roll Bonding

Cu-Al-Cu laminated composite was prepared with cold roll bonding process and annealing was carried out to study the phase evolution during the annealing process and its effect on the mechanical properties of the composite. The experimental results showed that after annealing the brittle intermetallics in the interface mainly includes Al4Cu9, AlCu and Al2Cu. With the increase of annealing temperature, the tensile strength of the composite decreases and the elongation shows a different variation which increases at the beginning and then decreases after a critical point. This phenomenon is related to the evolution of intermetallic compounds in the interface of the composite. It was also found that the crack source of the tensile sample is in the interface and delamination appeared at high annealing temperature (450 °C).

Effect of Annealing on Mechanical Properties of Copper Alloys Deformed at Cryogenic Temperature

2013 ◽  
Vol 745-746 ◽  
pp. 363-370 ◽  
Author(s):  
Xiao Xiang Wu ◽  
Yu Lan Gong ◽  
Shi Ying Ren ◽  
Jing Mei Tao ◽  
Yan Long ◽  
...  
Keyword(s):  
Mechanical Properties ◽  
Annealing Temperature ◽  
Uniform Elongation ◽  
Copper Alloys ◽  
Annealing Treatment ◽  
Annealing Process ◽  
Optimal Annealing Temperature ◽  
Elongation To Failure ◽  
Cold Rolled ◽  
Zn Alloys

The effect of annealing treatment on the mechanical properties and microstructure of cold-rolled Cu-20% Zn alloys was investigated in this work. Mechanical properties changed dramatically with the increase of temperature. According to the microhardness test, it can roughly concluded that 150 is the optimal annealing temperature for deformation, at which a uniform elongation increased from 1.4658% before annealing to about 6.89%, and the elongation to failure increased from 7.426% to 16.81% with the same strength almost retained. The changes of microstructure during the annealing process are mainly distributed to the improvement of mechanical properties.

Effect of Annealing on Microstructure and Properties for Semi-Solid Magnesium Strips

2011 ◽  
Vol 704-705 ◽  
pp. 581-585
Author(s):  
Ying Zhang ◽  
Jin Hua Xu ◽  
Shui Sheng Xie ◽  
Mao Peng Geng ◽  
Hong Min Guo ◽  
...  
Keyword(s):  
Grain Boundary ◽  
Annealing Temperature ◽  
Eutectic Structure ◽  
Annealing Process ◽  
Solidification Structure ◽  
Dispersion Strengthening ◽  
Roll Casting ◽  
Mg17al12 Phase ◽  
Equilibrium Solidification ◽  
Semi Solid

The experiment of the roll-casting for semi-solid AZ91D magnesium was carried out on the equipment made by ourselves in our laboratory. Parameters of annealing process and the effect of annealing temperature on structure and hardness of semi-solid magnesium were investigated. It was shown that annealing process can improve the structure and properties of roll-casting strips for semi-solid magnesium. In addition, it can relieve the eutectic structure segregation and make β-Mg17Al12 phase precipitate from primary α-Mg grain, which can cause dispersion strengthening process when the annealing temperature is about 420°C. With the increasing of annealing temperature, semi-solid primary α-Mg grain boundary become obscure gradually, grain growth is indistinct and β-Mg17Al12 phase is precipitated from the inner α-Mg grain. However, the aberrated eutectic α-Mg grain for non-equilibrium solidification increase continuously and separate gradually from β-Mg17Al12 phase, which makes the β-Mg17Al12 phase connect together and distribute on the α-Mg grain boundary closely approaching the equilibrium solidification structure. Hardness in eutectic structure area is higher than primary α-Mg grain. With the increasing of annealing temperature, hardness in eutectic structure area will increase and then decrease, when the temperature is over 400°C, the hardness will increase again, but hardness of primary α-Mg grain nearly unchanged. Keywords: casting-rolling; anneal; semi-solid; magnesium alloy; microstructure

scholarly journals Effect of Annealing Process on CH3NH3PbI3-XClX Film Morphology of Planar Heterojunction Perovskite Solar Cells with Optimal Compact TiO2 Layer

2017 ◽  
Vol 2017 ◽  
pp. 1-9 ◽  
Author(s):  
Dan Chen ◽  
Xiaoping Zou ◽  
Hong Yang ◽  
Ningning Zhang ◽  
Wenbin Jin ◽  
...  
Keyword(s):  
Solar Cells ◽  
Annealing Temperature ◽  
Photovoltaic Performance ◽  
Perovskite Solar Cells ◽  
Annealing Process ◽  
Film Morphology ◽  
Perovskite Layer ◽  
Optimal Procedures ◽  
Planar Heterojunction ◽  
Annealing Method

The morphology of compact TiO2 film used as an electron-selective layer and perovskite film used as a light absorption layer in planar perovskite solar cells has a significant influence on the photovoltaic performance of the devices. In this paper, the spin coating speed of the compact TiO2 is investigated in order to get a high-quality film and the compact TiO2 film exhibits pinhole- and crack-free films treated by 2000 rpm for 60 s. Furthermore, the effect of annealing process, including annealing temperature and annealing program, on CH3NH3PbI3-XClX film morphology is studied. At the optimal annealing temperature of 100°C, the CH3NH3PbI3-XClX morphology fabricated by multistep slow annealing method has smaller grain boundaries and holes than that prepared by one-step direct annealing method, which results in the reduction of grain boundary recombination and the increase of Voc. With all optimal procedures, a planar fluorine-doped tin oxide (FTO) substrate/compact TiO2/CH3NH3PbI3-XClX/Spiro-MeOTAD/Au cell is prepared for an active area of 0.1 cm2. It has achieved a power conversion efficiency (PCE) of 14.64%, which is 80.3% higher than the reference cell (8.12% PCE) without optimal perovskite layer. We anticipate that the annealing process with optimal compact TiO2 layer would possibly become a promising method for future industrialization of planar perovskite solar cells.

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