scholarly journals The migration mechanism of transition metal ions in LiNi0.5Mn1.5O4

2015 ◽  
Vol 3 (24) ◽  
pp. 13031-13038 ◽  
Author(s):  
Gui-Liang Xu ◽  
Yan Qin ◽  
Yang Ren ◽  
Lu Cai ◽  
Ke An ◽  
...  
Keyword(s):  
Transition Metal ◽  
Neutron Diffraction ◽  
Metal Ions ◽  
Transition Metal Ions ◽  
High Energy ◽  
X Ray Diffraction ◽  
X Ray ◽  
Migration Mechanism

In situ high-energy X-ray diffraction and neutron diffraction were deployed to trace the migration of transition metal ions in LiNi0.5Mn1.5O4.

Characterization on the Microstructures and Optical Performances of TiO2 Doped with Transition Metals

2014 ◽  
Vol 887-888 ◽  
pp. 388-394 ◽  
Author(s):  
Xin Hua Liu ◽  
Yi Deng ◽  
Yu Chuan Zhang ◽  
Yin Hang Zhou
Keyword(s):  
Transition Metal ◽  
Metal Ions ◽  
Photoelectron Spectroscopy ◽  
Transition Metal Ions ◽  
Ultraviolet Region ◽  
Visible Light Region ◽  
X Ray Diffraction ◽  
X Ray ◽  
Light Region ◽  
Cu Ions

The structures and optical performances of TiO2doped with 4thperiodic transition metal ions were investigated in this paper. The characterization results of X-ray photoelectron spectroscopy and X-ray diffraction showed that the transition metal ions existed in oxidative states, and composites formed because of the reaction between doped metal ions and TiO2. The absorption spectroscopy of TiO2doped with zinc was mainly in ultraviolet region, close to that of the pure TiO2. While for TiO2doped with other transition metal ions including V, Cr, Mn, Fe, Co, Ni and Cu ions, the absorption spectroscopies covered ultraviolet region and visible light region, much broader than that of the pure TiO2.

scholarly journals Effects of Transition Metal Ions on the Colour of Blue-Green Beryl

Minerals ◽  
2022 ◽  
Vol 12 (1) ◽  
pp. 86
Author(s):  
Hui Wang ◽  
Qiyun Guan ◽  
Yuchong Liu ◽  
Ying Guo
Keyword(s):  
Charge Transfer ◽  
Transition Metal ◽  
Metal Ions ◽  
Total Content ◽  
Transition Metal Ions ◽  
X Ray Diffraction ◽  
X Ray ◽  
Vis Spectroscopy ◽  
Industrial Cameras ◽  
Cielab Colour

This study reports the effects of transition metal ions on the colour of blue-green beryl. Industrial cameras were used to measure colour in the CIELAB colour space. X-ray fluorescence (XRF), X-ray diffraction (XRD), infrared spectroscopy (IR), and ultraviolet-visible (UV–vis) spectroscopy were used for characterization. The d–d transition of Fe3+ with sixfold coordination, the O2−→Fe3+ charge transfer, and the charge transition of binuclear metal M–M complexes formed by [Fe2(OH)4]2+ in the channel caused a yellow tone, whereas the charge transfer of Fe2+/Fe3+ with sixfold coordination caused a blue-green tone. The chroma of blue-green beryl was negatively correlated with the ratio of Cs+Mn to Fe contents. The lightness of blue-green beryl was negatively correlated with the total content of transition metal ions.

scholarly journals Stress-controlled decomposition routes in cubic AlCrN films assessed by in-situ high-temperature high-energy grazing incidence transmission X-ray diffraction

2019 ◽  
Vol 9 (1) ◽  
Author(s):  
M. Meindlhumer ◽  
S. Klima ◽  
N. Jäger ◽  
A. Stark ◽  
H. Hruby ◽  
...  
Keyword(s):  
High Temperature ◽  
Transition Metal ◽  
Stress Level ◽  
Grazing Incidence ◽  
High Energy ◽  
Metal Nitrides ◽  
Transition Metal Nitrides ◽  
X Ray Diffraction ◽  
X Ray

AbstractThe dependence of decomposition routes on intrinsic microstructure and stress in nanocrystalline transition metal nitrides is not yet fully understood. In this contribution, three Al0.7Cr0.3N thin films with residual stress magnitudes of −3510, −4660 and −5930 MPa in the as-deposited state were in-situ characterized in the range of 25–1100 °C using in-situ synchrotron high-temperature high-energy grazing-incidence-transmission X-ray diffraction and temperature evolutions of phases, coefficients of thermal expansion, structural defects, texture as well as residual, thermal and intrinsic stresses were evaluated. The multi-parameter experimental data indicate a complex intrinsic stress and phase changes governed by a microstructure recovery and phase transformations taking place above the deposition temperature. Though the decomposition temperatures of metastable cubic Al0.7Cr0.3N phase in the range of 698–914 °C are inversely proportional to the magnitudes of deposition temperatures, the decomposition process itself starts at the same stress level of ~−4300 MPa in all three films. This phenomenon indicates that the particular compressive stress level functions as an energy threshold at which the diffusion driven formation of hexagonal Al(Cr)N phase is initiated, provided sufficient temperature is applied. In summary, the unique synchrotron experimental setup indicated that residual stresses play a decisive role in the decomposition routes of nanocrystalline transition metal nitrides.

scholarly journals In-Situ High-Energy X-ray Diffraction Study of Austenite Decomposition During Rapid Cooling and Isothermal Holding in Two HSLA Steels

2021 ◽  
Vol 52 (5) ◽  
pp. 1812-1825
Author(s):  
Sen Lin ◽  
Ulrika Borggren ◽  
Andreas Stark ◽  
Annika Borgenstam ◽  
Wangzhong Mu ◽  
...  
Keyword(s):  
Isothermal Holding ◽  
Weight Percent ◽  
High Energy ◽  
Decomposition Kinetics ◽  
Bainitic Transformation ◽  
Austenite Decomposition ◽  
X Ray Diffraction ◽  
Rapid Cooling ◽  
X Ray

AbstractIn-situ high-energy X-ray diffraction experiments with high temporal resolution during rapid cooling (280 °C s−1) and isothermal heat treatments (at 450 °C, 500 °C, and 550 °C for 30 minutes) were performed to study austenite decomposition in two commercial high-strength low-alloy steels. The rapid phase transformations occurring in these types of steels are investigated for the first time in-situ, aiding a detailed analysis of the austenite decomposition kinetics. For the low hardenability steel with main composition Fe-0.08C-1.7Mn-0.403Si-0.303Cr in weight percent, austenite decomposition to polygonal ferrite and bainite occurs already during the initial cooling. However, for the high hardenability steel with main composition Fe-0.08C-1.79Mn-0.182Si-0.757Cr-0.094Mo in weight percent, the austenite decomposition kinetics is retarded, chiefly by the Mo addition, and therefore mainly bainitic transformation occurs during isothermal holding; the bainitic transformation rate at the isothermal holding is clearly enhanced by lowered temperature from 550 °C to 500 °C and 450 °C. During prolonged isothermal holding, carbide formation leads to decreased austenite carbon content and promotes continued bainitic ferrite formation. Moreover, at prolonged isothermal holding at higher temperatures some degenerate pearlite form.

scholarly journals Dislocation densities in a low-carbon steel during martensite transformation determined by in situ high energy X-Ray diffraction

2021 ◽  
Vol 800 ◽  
pp. 140249
Author(s):  
Juan Macchi ◽  
Steve Gaudez ◽  
Guillaume Geandier ◽  
Julien Teixeira ◽  
Sabine Denis ◽  
...  
Keyword(s):  
Carbon Steel ◽  
Martensite Transformation ◽  
Low Carbon Steel ◽  
High Energy ◽  
Low Carbon ◽  
X Ray Diffraction ◽  
X Ray ◽  
Dislocation Densities
Sign in / Sign up

Export Citation Format

Share Document