scholarly journals Effect of Al (III) Ions on the Separation of Cassiterite and Clinochlore Through Reverse Flotation

Minerals ◽  
2018 ◽  
Vol 8 (8) ◽  
pp. 347 ◽  
Author(s):  
Yumeng Chen ◽  
Xiong Tong ◽  
Dongxia Feng ◽  
Xian Xie
Keyword(s):  
Contact Angle ◽  
Photoelectron Spectroscopy ◽  
Interaction Mechanism ◽  
Reverse Flotation ◽  
X Ray ◽  
Angle Measurements ◽  
Mineral Flotation ◽  
Contact Angle Measurements ◽  
Flotation Performance ◽  
Hydrophobic Clay

Most hydrophobic clay minerals, such as clinochlore, are known to cause problems in the recovery of cassiterite. In this study, a new reagent scheme, i.e., sodium oleate (NaOL) as a collector and Al (III) ions as a depressant, for reverse flotation separation of cassiterite and clinochlore was investigated. The flotation performance and interaction mechanism were studied by microflotation tests, adsorption tests, contact angle measurements, and X-ray photoelectron spectroscopy (XPS) analysis. Results of single mineral flotation experiments showed that NaOL had a different flotation performance on cassiterite and clinochlore, and the addition of Al (III) ions could selectively inhibit the floatability of cassiterite. Reverse flotation tests performed on mixed minerals indicated that the separation of cassiterite and clinochlore could be achieved in the presence of NaOL and Al (III) ions. Adsorption experiments demonstrated that Al (III) ions hindered the adsorption of NaOL on cassiterite surfaces but exerted little influence on the adsorption of NaOL on clinochlore surfaces. Results of contact angle measurements indicated that Al (III) ions could impede the hydrophobization process of cassiterite in NaOL solution. XPS results showed that aluminum species were adsorbed onto the cassiterite surfaces through the interaction with O sites.

scholarly journals Surface Modification of the Alloy Ti-7.5Mo by Anodization for Biomedical Applications

2016 ◽  
Vol 869 ◽  
pp. 913-917 ◽  
Author(s):  
Ana Lucia do Amaral Escada ◽  
Javier Andres Muñoz Chaves ◽  
Ana Paula Rosifini Alves Claro
Keyword(s):  
Contact Angle ◽  
Electron Microscope ◽  
Biomedical Applications ◽  
Anatase Phase ◽  
Ammonium Fluoride ◽  
X Ray ◽  
Angle Measurements ◽  
Contact Angle Measurements ◽  
Simple Surface ◽  
Scanning Electron

The purpose of this study was to evaluate the TiO2 nanotubes growth and the variation in its diameter to improve the surface properties of Ti-7.5Mo to use for biomedical applications. For the nanotubes TiO2 growth, the samples were anodized in glycerol and ammonium fluoride and divided according to the anodizing potential at 5V to 10V and 24 hour time. The surfaces were examined by scanning electron microscope (SEM), X-ray analysis (XRD) and contact angle measurements. The average tube diameter, ranging in size from 13 to 23 nm, was found to increase with increasing anodizing voltage. It was also observed a decrease in contact angle in accordance with the increase in the anodizing potential. The X-ray analysis showed the presence of anatase phase in samples whose potential was 10V and this condition represents a simple surface treatment for Ti-7.5Mo alloy that has high potential for biomedical applications.

scholarly journals Effect of Hydrodynamic Cavitation Assistance on Different Stages of Coal Flotation

Minerals ◽  
2020 ◽  
Vol 10 (3) ◽  
pp. 221
Author(s):  
Hua Han ◽  
An Liu ◽  
Huaifa Wang
Keyword(s):  
Contact Angle ◽  
Hydrodynamic Cavitation ◽  
Screening Tests ◽  
Separation Stage ◽  
Coal Flotation ◽  
Angle Measurements ◽  
Coal Particles ◽  
Constant Rate ◽  
Contact Angle Measurements ◽  
Flotation Performance

In this study, the effect of hydrodynamic cavitation (HC) on the conditioning stage (HCCS), separation stage (HCSS), and whole stage (HCWS) of coal flotation was investigated by flotation tests, laser granulometry, and contact angle measurements. The flotation results indicate that compared to conventional flotation, all HC-assisted flotation methods can improve concentrate combustible recovery and flotation constant rate. HCCS and HCSS show similar levels of improvement, while HCWS has a better flotation efficiency. The screening tests demonstrate that HC has the advantage of being able to liberate coarse coal particles (+0.25 mm) prior to being combined with gangues. On one hand, HC promotes the dispersion of both particles and agents, while longer cavitation time in HCCS does not lead to better flotation performance. On the other hand, enhancement of the adsorption of the collector on the surface of coal particles in HCCS is confirmed by flotation concentrate contact angle tests. However, HCSS leads to a decrease in concentrate hydrophobicity, compared to conventional flotation. The micro-nanobubbles generated by HC play an important role in improving flotation performance. HCWS offers the advantages of both HCCS and HCSS, and the cooperated mechanism of different HC modes enhances the recovery of coal particles in flotation.

Effect of electron irradiation on the Crystallite size, Grain size and Contact angle of electrodeposited Cadmium Telluride thin films

2015 ◽  
Vol 8 (2) ◽  
Author(s):  
S. A. Gangawane ◽  
V. P. Malekar ◽  
V. J. Fulari
Keyword(s):  
Thin Films ◽  
Contact Angle ◽  
Grain Size ◽  
Electron Beam Irradiation ◽  
Crystal Size ◽  
X Ray Diffraction ◽  
X Ray ◽  
Angle Measurements ◽  
Contact Angle Measurements ◽  
Cdte Thin Films

In this paper, the effects of electron beam irradiation on the CdTe thin films are studied. The CdTe thin films are characterized by X-ray diffraction (XRD), scanning electron microscope (SEM) and contact angle measurements for different bath concentration. The thin film layers are subjected to irradiation of 6 MeV electrons. Finally the effect of irradiation is correlated to crystal size, grain size and contact angle measurements of the CdTe thin films

Surface Modification of Fluorosilicone Acrylate RGP Contact Lens by Low-Temperature Ammonia Plasma

2009 ◽  
Vol 610-613 ◽  
pp. 1273-1277 ◽  
Author(s):  
Li Ren ◽  
Lian Na Zhao ◽  
Shi Heng Yin ◽  
Ying Jun Wang ◽  
Hao Chen ◽  
...  
Keyword(s):  
Contact Angle ◽  
Low Temperature ◽  
Plasma Treatment ◽  
Contact Lens ◽  
Photoelectron Spectroscopy ◽  
Ammonia Plasma ◽  
Angle Measurements ◽  
Atomic Force ◽  
Contact Angle Measurements ◽  
Surface Contact Angle

In order to improve the surface hydrophilicity and the resistance to protein deposition of fluorosilicone acrylate RGP (rigid gas permeable) contact lens, low temperature ammonia plasma treatment was used to modify the lens surface. The changes of surface structures and properties were characterized by contact angle analyzer, X-ray photoelectron spectroscopy (XPS) and atomic force microscope (AFM). Effects of exposure time and plasma generating power on surface properties of the RGP contact lens were investigated. The surface contact angle measurements showed a great improvement of hydrophilicity after plasma treatment. XPS analysis indicated that the oxygen content and the nitrogen content increased remarkably after ammonia plasma treatment. Furthermore, the content of the hydrophilic group O-C=O/N-C=O on the surface increased and the content of the hydrophobic group CF2 decreased after plasma treatment. AFM results showed that ammonia plasma could lead to surface etching.

scholarly journals The Sensitivity of Estimates of Multiphase Fluid and Solid Properties of Porous Rocks to Image Processing

2019 ◽  
Vol 131 (3) ◽  
pp. 985-1005 ◽  
Author(s):  
Gaetano Garfi ◽  
Cédric M. John ◽  
Steffen Berg ◽  
Samuel Krevor
Keyword(s):  
Image Processing ◽  
Contact Angle ◽  
Surface Area ◽  
Single Phase ◽  
Phase Flow ◽  
Single Phase Flow ◽  
X Ray ◽  
Angle Measurements ◽  
Contact Angle Measurements

AbstractX-ray microcomputed tomography (X-ray μ-CT) is a rapidly advancing technology that has been successfully employed to study flow phenomena in porous media. It offers an alternative approach to core scale experiments for the estimation of traditional petrophysical properties such as porosity and single-phase flow permeability. It can also be used to investigate properties that control multiphase flow such as rock wettability or mineral topology. In most applications, analyses are performed on segmented images obtained employing a specific processing pipeline on the greyscale images. The workflow leading to a segmented image is not straightforward or unique and, for most of the properties of interest, a ground truth is not available. For this reason, it is crucial to understand how image processing choices control properties estimation. In this work, we assess the sensitivity of porosity, permeability, specific surface area, in situ contact angle measurements, fluid–fluid interfacial curvature measurements and mineral composition to processing choices. We compare the results obtained upon the employment of two processing pipelines: non-local means filtering followed by watershed segmentation; segmentation by a manually trained random forest classifier. Single-phase flow permeability, in situ contact angle measurements and mineral-to-pore total surface area are the most sensitive properties, as a result of the sensitivity to processing of the phase boundary identification task. Porosity, interfacial fluid–fluid curvature and specific mineral descriptors are robust to processing. The sensitivity of the property estimates increases with the complexity of its definition and its relationship to boundary shape.

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