scholarly journals The Limitations of 5f Delocalization and Dispersion

2021 ◽  
Vol 11 (9) ◽  
pp. 3882
Author(s):  
J. G. Tobin ◽  
S. Nowak ◽  
S. W. Yu ◽  
R. Alonso-Mori ◽  
T. Kroll ◽  
...  
Keyword(s):  
Photoelectron Spectroscopy ◽  
Emission Spectroscopy ◽  
X Ray ◽  
Fundamental Limitations ◽  
Important Phenomenon ◽  
Novel Approach

Delocalization in the 5f states of the actinides is an important phenomenon, but poorly quantified. Here, the fundamental limitations of 5f dispersion measurements using angle and momentum resolved variants of photoelectron spectroscopy will be discussed. A novel approach will be suggested, based on a theoretical projection, which should circumvent these limitations: M4,5 X-ray emission spectroscopy. This analysis will utilize the case study of U metal, which can be considered to be the paramount example of 5f dispersion.

Synthesis and characterizations of TiN–SBA-15 mesoporous materials for CO2 dry reforming enhancement

2020 ◽  
Vol 92 (4) ◽  
pp. 545-556
Author(s):  
Maslin Chotirach ◽  
Supawan Tantayanon ◽  
Duangamol Nuntasri Tungasmita ◽  
Junliang Sun ◽  
Sukkaneste Tungasmita
Keyword(s):  
Photoelectron Spectroscopy ◽  
Synthesis Method ◽  
High Specific Surface Area ◽  
Dry Reforming ◽  
Dry Reforming Of Methane ◽  
Ni Catalyst ◽  
X Ray ◽  
Novel Approach ◽  
Temperature Programmed ◽  
Adsorption Desorption

AbstractA novel approach of titanium nitride (TiN) incorporated into SBA-15 framework was developed using one-step hydrothermal synthesis method. TiN contents up to ~18 wt% were directly dispersed in a synthetic gel under a typical strong acidic condition. The physico-chemical characteristics and the surface properties were investigated by means of X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), Fourier transform infrared spectroscopy (FTIR), N2 adsorption-desorption, field emission scanning electron microscope (FESEM) equipped with energy dispersive X-ray spectroscopy (EDS), wavelength dispersive X-ray fluorescence (WDXRF) and CO2-temperature programmed desorption (CO2-TPD). The results indicated that the highly ordered mesostructured was effectively maintained with high specific surface area of 532–685 m2g−1. The basicity of the modified SBA-15 increased with rising TiN loading. These modified materials were applied as a support of Ni catalyst in dry reforming of methane (DRM). Their catalytic behavior possessed superior conversions for both CO2 and CH4 with the highest H2/CO ratio (0.83) as well as 50 % lower carbon formation, compared to bare SBA-15 support.

scholarly journals Bio-Performance of Hydrothermally and Plasma-Treated Titanium: The New Generation of Vascular Stents

2021 ◽  
Vol 22 (21) ◽  
pp. 11858
Author(s):  
Metka Benčina ◽  
Niharika Rawat ◽  
Katja Lakota ◽  
Snežna Sodin-Šemrl ◽  
Aleš Iglič ◽  
...  
Keyword(s):  
Hydrothermal Treatment ◽  
Photoelectron Spectroscopy ◽  
Surface Engineering ◽  
Vascular Endothelial Cells ◽  
Surface Characteristics ◽  
Water Contact ◽  
X Ray ◽  
Vascular Stents ◽  
Novel Approach ◽  
Treatment Procedures

The research presented herein follows an urgent global need for the development of novel surface engineering techniques that would allow the fabrication of next-generation cardiovascular stents, which would drastically reduce cardiovascular diseases (CVD). The combination of hydrothermal treatment (HT) and treatment with highly reactive oxygen plasma (P) allowed for the formation of an oxygen-rich nanostructured surface. The morphology, surface roughness, chemical composition and wettability of the newly prepared oxide layer on the Ti substrate were characterized by scanning electron microscopy (SEM) with energy-dispersive X-ray analysis (EDX), atomic force microscopy (AFM), X-ray photoelectron spectroscopy (XPS) and water contact angle (WCA) analysis. The alteration of surface characteristics influenced the material’s bio-performance; platelet aggregation and activation was reduced on surfaces treated by hydrothermal treatment, as well as after plasma treatment. Moreover, it was shown that surfaces treated by both treatment procedures (HT and P) promoted the adhesion and proliferation of vascular endothelial cells, while at the same time inhibiting the adhesion and proliferation of vascular smooth muscle cells. The combination of both techniques presents a novel approach for the fabrication of vascular implants, with superior characteristics.

Electronic Structure of h-WO3 and CuWO4 Nanocrystals, Harvesting Materials for Renewable Energy Systems and Functional Devices

2011 ◽  
Vol 110-116 ◽  
pp. 2188-2193 ◽  
Author(s):  
V.V. Atuchin ◽  
I.B. Troitskaia ◽  
O.Yu. Khyzhun ◽  
V.L. Bekenev ◽  
Yu.M. Solonin
Keyword(s):  
Electronic Structure ◽  
Renewable Energy ◽  
Valence Band ◽  
Photoelectron Spectroscopy ◽  
Emission Spectroscopy ◽  
Energy Production ◽  
Energy Systems ◽  
Renewable Energy Systems ◽  
X Ray ◽  
Valence Band Region

— The electronic structure of hexagonal WO3 and triclinic CuWO4 nanocrystals, prospective materials for renewable energy production and functional devices, has been studied using the X-ray photoelectron spectroscopy (XPS) and X-ray emission spectroscopy (XES) methods. The present XPS and XES results render that the W 5d-and O 2p-like states contribute throughout the whole valence-band region of the h-WO3 and CuWO4 nanocrystalline materialls, however maximum contributions of the O 2p-like states occur in the upper, whilst the W 5d-like states in the lower portions of the valence band, respectively.

scholarly journals X-ray Photoelectron Spectroscopy Study of Electronic Structure of Graphene Nanosheets

2015 ◽  
Vol 16 (2) ◽  
pp. 289-292
Author(s):  
B.I. Ilkiv ◽  
S.S. Petrovska ◽  
R.A. Sergienko ◽  
О.О. Foya ◽  
O.V. Ilkiv ◽  
...  
Keyword(s):  
Electron Microscopy ◽  
Transmission Electron Microscopy ◽  
Photoelectron Spectroscopy ◽  
Emission Spectroscopy ◽  
Graphene Nanosheets ◽  
Oxygen Removal ◽  
Electron Bombardment ◽  
Spectroscopy Study ◽  
X Ray ◽  
Transmission Electron

Investigations of graphene nanosheets and oxidized graphene nanosheets were carried out using X-ray photoelectron spectroscopy. Scanning and transmission electron microscopy investigations were used in addition to X-ray photoelectron spectroscopy. It was found that functional carboxyl and epoxide groups were removed from samples due to argon bombardment in studies of oxidized graphene nanosheets with X-ray photoelectron spectroscopy. Thus the ОKα-band was not revealed in oxidized graphene nanosheets owing to oxygen removal due to electron bombardment with the use of. ultra-soft X-ray emission spectroscopy. 

Sign in / Sign up

Export Citation Format

Share Document