scholarly journals Inhibition mechanism of Ca 2+ , Mg 2+ and Fe 3+ in fine cassiterite flotation using octanohydroxamic acid

2018 ◽  
Vol 5 (8) ◽  
pp. 180158 ◽  
Author(s):  
Liuyi Ren ◽  
Hang Qiu ◽  
Wenqing Qin ◽  
Ming Zhang ◽  
Yubiao Li ◽  
...  
Keyword(s):  
Contact Angle ◽  
Photoelectron Spectroscopy ◽  
Chemical Properties ◽  
Solution Chemistry ◽  
Inhibition Mechanism ◽  
X Ray ◽  
Force Microscopy ◽  
Atomic Force ◽  
Afm Imaging ◽  
Flotation Performance

The existence of metal ions should not be ignored in both hydrometallurgy and flotation. In this study, the effects of Ca 2+ , Mg 2+ and Fe 3+ on the flotation performance of cassiterite using octanohydroxamic acid (OHA) as the collector were investigated by micro-flotation tests, X-ray photoelectron spectroscopy (XPS), Fourier transform infrared (FTIR) spectroscopy, contact angle, zeta ( ζ ) potential measurements and atomic force microscopy (AFM) imaging. The results of the flotation and contact angle experiments showed that the addition of Ca 2+ , Mg 2+ and Fe 3+ significantly decreased both the recovery and contact angle of cassiterite with pH ranged from 6.0 to 12.0 in the presence of OHA collector. ζ- Potential measurements, solution chemistry analysis and FTIR measurements indicated that the flotation recovery of the cassiterite declined due to the CaOH + , MgOH + and Fe(OH) 3 sites on the cassiterite surface. XPS results indicated that the chemisorption of OHA and calcium ions on the cassiterite surface finally changed its chemical properties. The AFM images also revealed that new species Fe(OH) 3 of Fe 3+ formed and adsorbed on the cassiterite surface at pH 9.0. The adsorption of Fe(OH) 3 reduced the adsorption of OHA on the cassiterite surface, thus the hydrophobicity of cassiterite was deteriorated.

Optical and Structural Properties of TiO2 Films Deposited from Different Titanium Oxide Materials by Electron Beam

2010 ◽  
Vol 663-665 ◽  
pp. 401-404
Author(s):  
Feng Xiang Wang ◽  
Chang Kwon Hwangbo ◽  
Bu Yong Jung ◽  
Jun He Qi
Keyword(s):  
Photoelectron Spectroscopy ◽  
Near Infrared ◽  
Chemical Properties ◽  
X Ray Diffraction ◽  
Tio2 Thin Films ◽  
X Ray ◽  
Force Microscopy ◽  
Atomic Force ◽  
Source Materials ◽  
Deposited Films

TiO2 thin films were deposited from Ti2¬O3, TiO2 and Ti3O5 source materials by e-beam. The refractive index and extinction coefficient of the films in the visible and near infrared（IR） region were measured. The structural and chemical properties of the films were investigated by x-ray diffraction (XRD), atomic force microscopy (AFM) and x-ray photoelectron spectroscopy (XPS). XRD measurements revealed that all the deposited films were amorphous. XPS analysis showed the films were stoichiometric TiO2. The AFM investigation confirmed that the surface roughness of the films was dependent on the deposition conditions.

scholarly journals Chemical, electrochemical and surface morphology investigation of Cichorium intybus extract (CIE) as beneficial inhibitor for Al in 2 M HCl acid

2020 ◽  
Vol 9 (2) ◽  
pp. 1064-1073
Keyword(s):  
Surface Morphology ◽  
Photoelectron Spectroscopy ◽  
Electrochemical Impedance ◽  
Inhibition Mechanism ◽  
X Ray ◽  
Force Microscopy ◽  
Tafel Polarization ◽  
Atomic Force ◽  
Chemical Strategies ◽  
Hcl Medium

The inhibiting activity of CIE(CIE) to the dissolution of Al in 2M HCl medium was carried out by chemical strategies (mass loss and gasometry) and electrochemical systems, for example, tafel polarization (TP), electrochemical impedance spectroscopy (EIS) and electrochemical frequency modulation (EFM). Surface morphology was examined utilizing atomic force microscopy (AFM) and x-ray photoelectron spectroscopy (XPS). Fourier transform infrared spectroscopy (FTIR) outcomes indicated that the inhibition mechanism was by adsorption process through the functional groups that exist in the investigated extract. The results demonstrated that the inhibiting efficiency expanded with expanding amounts of the extract. Polarization information demonstrated that CIE goes about as an inhibitor of mixed type. The procedure of adsorption on Al surface ascribed to Langmuir isotherm. All thermodynamic calculations were determined and discussed. The inhibitive efficiencies obtained from all utilized procedures have acceptable values.

scholarly journals Surface Modification of Polyethersulfone (PES) with UV Photo-Oxidation

Technologies ◽  
2021 ◽  
Vol 9 (2) ◽  
pp. 36
Author(s):  
Ibrahim Cisse ◽  
Sarah Oakes ◽  
Shreen Sachdev ◽  
Marc Toro ◽  
Shin Lutondo ◽  
...  
Keyword(s):  
Surface Roughness ◽  
Contact Angle ◽  
Atomic Force Microscopy ◽  
Photoelectron Spectroscopy ◽  
Water Contact ◽  
X Ray ◽  
Force Microscopy ◽  
Photo Oxidation ◽  
Atomic Force ◽  
Modified Surfaces

Polyethersulfone (PES) films are widely employed in the construction of membranes where there is a desire to make the surface more hydrophilic. Therefore, UV photo-oxidation was studied in order to oxidize the surface of PES and increase hydrophilicity. UV photo-oxidation using low pressure mercury lamps emitting both 253.7 and 184.9 nm radiation were compared with only 253.7 nm photons. The modified surfaces were characterized using X-ray photoelectron spectroscopy (XPS), atomic force microscopy (AFM), and water contact angle (WCA) measurements. Both sets of lamps gave similar results, showing an increase of the oxygen concentration up to a saturation level of ca. 29 at.% and a decrease in the WCA, i.e., an increase in hydrophilicity, down to ca. 40°. XPS detected a decrease of sp2 C-C aromatic group bonding and an increase in the formation of C-O, C=O, O=C-O, O=C-OH, O-(C=O)-O, and sulphonate and sulphate moieties. Since little change in surface roughness was observed by AFM, the oxidation of the surface caused the increase in hydrophilicity.

Development of quasi-two-dimensional Nb2O5 nanoflakes with thickness-depended electro-chemical properties

2015 ◽  
Vol 08 (01) ◽  
pp. 1550007 ◽  
Author(s):  
Serge Zhuiykov ◽  
Eugene Kats ◽  
Tomoaki Sato ◽  
Hiroshi Ikeda ◽  
Norio Miura
Keyword(s):  
Photoelectron Spectroscopy ◽  
Sol Gel ◽  
Chemical Properties ◽  
Two Dimensional ◽  
X Ray Diffraction ◽  
Conductive Atomic Force Microscopy ◽  
X Ray ◽  
Force Microscopy ◽  
Atomic Force ◽  
Structural Surface

Quasi-two-dimensional (Q2D) Nb 2 O 5 nanoflakes were synthesized by combined sol–gel/exfoliation method with the average thickness of 10–25 nm. Their structural, surface- and electro-chemical properties were closely studied and analyzed by X-ray diffraction (XRD), energy dispersive X-ray spectroscopy (EDX), scanning electron microscopy (SEM), conductive atomic force microscopy (AFM), Fourier transform infrared (FTIR) spectroscopy, X-ray photoelectron spectroscopy (XPS) and Raman spectroscopy techniques.

scholarly journals UV Photo-Oxidation of Polybenzimidazole (PBI)

Technologies ◽  
2020 ◽  
Vol 8 (4) ◽  
pp. 52
Author(s):  
Devon Shedden ◽  
Kristen M. Atkinson ◽  
Ibrahim Cisse ◽  
Shin Lutondo ◽  
Tyshawn Roundtree ◽  
...  
Keyword(s):  
Contact Angle ◽  
Photoelectron Spectroscopy ◽  
Treatment Time ◽  
Aerospace Industry ◽  
Water Contact ◽  
X Ray ◽  
Force Microscopy ◽  
Photo Oxidation ◽  
Redox Flow Batteries ◽  
Atomic Force

Since polybenzimidazole (PBI) is often used in the aerospace industry, high-temperature fuel cells, and in redox flow batteries, this research investigated the surface modification of PBI film with 253.7 and 184.9 nm UV photo-oxidation. As observed by X-ray photoelectron spectroscopy (XPS), the oxygen concentration on the surface increased up to a saturation level of 20.2 ± 0.7 at %. With increasing treatment time, there were significant decreases in the concentrations of C-C sp2 and C=N groups and increases in the concentrations of C=O, O-C=O, O-(C=O)-O, C-N, and N-C=O containing moieties due to 253.7 nm photo-oxidation of the aromatic groups of PBI and reaction with ozone produced by 184. 9 nm photo-dissociation of oxygen. Because no significant changes in surface topography were detected by Atomic Force Microscopy (AFM) and SEM measurements, the observed decrease in the water contact angle down to ca. 44°, i.e., increase in hydrophilic, was due to the chemical changes on the surface.

Investigation of the Effect of Uv-Assisted Oxidation and Nitridation of Hafnium Metal Films

2003 ◽  
Vol 780 ◽  
Author(s):  
C. Essary ◽  
V. Craciun ◽  
J. M. Howard ◽  
R. K. Singh
Keyword(s):  
Uv Radiation ◽  
Photoelectron Spectroscopy ◽  
Grazing Angle ◽  
X Ray Diffraction ◽  
Metal Thin Films ◽  
X Ray ◽  
Force Microscopy ◽  
Si Substrates ◽  
Atomic Force ◽  
Silicon Interface

AbstractHf metal thin films were deposited on Si substrates using a pulsed laser deposition technique in vacuum and in ammonia ambients. The films were then oxidized at 400 °C in 300 Torr of O2. Half the samples were oxidized in the presence of ultraviolet (UV) radiation from a Hg lamp array. X-ray photoelectron spectroscopy, atomic force microscopy, and grazing angle X-ray diffraction were used to compare the crystallinity, roughness, and composition of the films. It has been found that UV radiation causes roughening of the films and also promotes crystallization at lower temperatures.Furthermore, increased silicon oxidation at the interface was noted with the UVirradiated samples and was shown to be in the form of a mixed layer using angle-resolved X-ray photoelectron spectroscopy. Incorporation of nitrogen into the film reduces the oxidation of the silicon interface.

Curcumin delivery by modified biosourced carbon-based nanoparticles

Nanomedicine ◽  
2022 ◽  
Author(s):  
Hossein Danafar ◽  
Marziyeh Salehiabar ◽  
Murat Barsbay ◽  
Hossein Rahimi ◽  
Mohammadreza Ghaffarlou ◽  
...  
Keyword(s):  
Photoelectron Spectroscopy ◽  
Free System ◽  
X Ray ◽  
Force Microscopy ◽  
Atomic Force ◽  
Transmission Electron ◽  
Good Biocompatibility ◽  
Drug Free ◽  
Mcf 7 ◽  
Carbon Based

Aim: To prepare a novel hybrid system for the controlled release and delivery of curcumin (CUR). Methods: A method for the ultrasound-assisted fabrication of protein-modified nanosized graphene oxide-like carbon-based nanoparticles (CBNPs) was developed. After being modified with bovine serum albumin (BSA), CUR was loaded onto the synthesized hybrid (labeled CBNPs@BSA–CUR). The structure and properties of the synthesized nanoparticles were elucidated using transmission electron microscopy (TEM), atomic force microscopy (AFM), ultraviolet-visible spectroscopy (UV-Vis), Fourier-transform infrared spectroscopy (FTIR) and x-ray photoelectron spectroscopy (XPS) methods. Results: CBNPs@BSA–CUR showed pH sensitivity and were calculated as controlled CUR release behavior. The drug-free system exhibited good biocompatibility and was nontoxic. However, CBNPs@BSA–CUR showed acceptable antiproliferative ability against MCF-7 breast cancer cells. Conclusion: CBNPs@BSA–CUR could be considered a highly promising nontoxic nanocarrier for the delivery of CUR with good biosafety.

Effect of Surface Chemistry on Ruthenium Wet Etching

2021 ◽  
Vol 314 ◽  
pp. 302-306
Author(s):  
Quoc Toan Le ◽  
E. Kesters ◽  
M. Doms ◽  
Efrain Altamirano Sánchez
Keyword(s):  
Surface Roughness ◽  
Photoelectron Spectroscopy ◽  
Etching Rate ◽  
Wet Etching ◽  
X Ray ◽  
Force Microscopy ◽  
Metal Free ◽  
Atomic Force ◽  
Different Types ◽  
Effect Of Surface

Different types of ALD Ru films, including as-deposited, annealed Ru, without and with a subsequent CMP step, were used for wet etching study. With respect to the as-deposited Ru, the etching rate of the annealed Ru film in metal-free chemical mixtures (pH = 7-9) was found to decrease substantially. X-ray photoelectron spectroscopy characterization indicated that this behavior could be explained by the presence of the formation of RuOx (x = 2,3) caused by the anneal. A short CMP step applied to the annealed Ru wafer removed the surface RuOx, at least partially, resulting in a significant increase of the etching rate. The change in surface roughness was quantified using atomic force microscopy.

Investigation of Ti/CuO interface by X-ray photoelectron spectroscopy and atomic force microscopy

2018 ◽  
Vol 51 (2) ◽  
pp. 246-253
Author(s):  
Dev Raj Chopra ◽  
Justin Seth Pearson ◽  
Darius Durant ◽  
Ritesh Bhakta ◽  
Anil R. Chourasia
Keyword(s):  
Atomic Force Microscopy ◽  
Photoelectron Spectroscopy ◽  
X Ray ◽  
Force Microscopy ◽  
Atomic Force
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