scholarly journals Effect of Ferric Ions on Sulfidization Flotation of Oxidize Digenite Fine Particles and Their Significance

Minerals ◽  
2021 ◽  
Vol 11 (3) ◽  
pp. 305
Author(s):  
Jiwei Xue ◽  
Dawei Ren ◽  
Sen Wang ◽  
Xianzhong Bu ◽  
Zhenguo Song ◽  
...  
Keyword(s):  
Photoelectron Spectroscopy ◽  
Iron Sulfide ◽  
Fine Particles ◽  
Surface Hydrophobicity ◽  
Ferric Ions ◽  
Angle Measurements ◽  
The Poor ◽  
Contact Angle Measurements ◽  
Iron Sulfide Minerals ◽  
Microscopy Analysis

Digenite fine particles are easily oxidized and ferric ions (Fe3+) commonly exist in the flotation pulp of digenite. This study investigated the effect of Fe3+ on the sulfidization flotation of oxidized digenite fine particles using sodium butyl xanthate (SBX) as a collector. The results of microflotation experiments show that the flotation rate and recovery of oxidized digenite fine particles can be improved by adding Na2S and SBX, whereas the existence of large amounts of Fe3+ is not beneficial for the sulfidization flotation of digenite. The results of Fe3+ adsorption, zeta potential, and contact angle measurements indicate that Fe3+ can be adsorbed on the digenite surface mainly in the form of Fe(OH)3, which hinders the adsorption of SBX and significantly reduces the surface hydrophobicity of digenite. X-ray photoelectron spectroscopy analysis further suggests that the poor surface hydrophobicity of digenite in the presence of Fe3+ is due to the production of large amounts of hydrophilic iron and copper oxides/hydroxides on the surface. Furthermore, optical microscopy analysis shows that these hydrophilic species effectively disperse digenite fine particles in the pulp, which eventually leads to the poor floatability of digenite. Therefore, it is necessary to reduce the amount of Fe3+ present in the pulp and adsorbed on digenite surface before sulfidization to realize effective separation of oxidized digenite fine particles and iron sulfide minerals.

scholarly journals Protection of LiFePO4 against Moisture

Materials ◽  
2020 ◽  
Vol 13 (4) ◽  
pp. 942 ◽  
Author(s):  
Nicolas Delaporte ◽  
Michel L. Trudeau ◽  
Daniel Bélanger ◽  
Karim Zaghib
Keyword(s):  
Photoelectron Spectroscopy ◽  
Inductively Coupled Plasma ◽  
Atomic Emission ◽  
Carbon Surface ◽  
Water Contact ◽  
Inductively Coupled ◽  
Spontaneous Reduction ◽  
Angle Measurements ◽  
Contact Angle Measurements ◽  
Carbon Coated

In this study, a carbon-coated LiFePO4 (LFP/C) powder was chemically grafted with trifluoromethylphenyl groups in order to increase its hydrophobicity and to protect it from moisture. The modification was carried out by the spontaneous reduction of in situ generated 4-trifluoromethylphenyl ions produced by the diazotization of 4-trifluoromethylaniline. X-ray photoelectron spectroscopy was used to analyze the surface organic species of the modified powder. The hydrophobic properties of the modified powder were investigated by carrying out its water contact angle measurements. The presence of the trifluoromethylphenyl groups on the carbon-coated LiFePO4 powder increased its stability in deionized water and reduced its iron dissolution in the electrolyte used for assembling the battery. The thermogravimetric and inductively coupled plasma atomic emission spectroscopy analyses revealed that 0.2–0.3 wt.% Li was deinserted during grafting and that the loading of the grafted molecules varied from 0.5 to 0.8 wt.% depending on the reaction conditions. Interestingly, the electrochemical performance of the modified LFP/C was not adversely affected by the presence of the trifluoromethylphenyl groups on the carbon surface. The chemical relithiation of the grafted samples was carried out using LiI as the reducing agent and the lithium source in order to obtain fully lithiated grafted powders.

Evaluation of the Role of Surfactant on the Surface Characterisation of Coal

2013 ◽  
Vol 634-638 ◽  
pp. 755-758
Author(s):  
Liang Gong ◽  
Zhi Yuan Yang ◽  
Jiang Long
Keyword(s):  
Sodium Dodecyl ◽  
Surface Hydrophobicity ◽  
Coal Surface ◽  
Surface Characterisation ◽  
Angle Measurements ◽  
Contact Angle Measurements ◽  
Higher Rank ◽  
The Impact ◽  
Coal Type

The surfaces of three China coals varying widely in coal type(Baode,Xiangshan,Jincheng) have been modified by adsorption of three surfactants( Sodium dodecyl sulfate,Polyethoxylated fatty alcohols,Alkyl phenol gather oxygen vinyl ether).The impact about coals of the surfactant has been explored by correlating three chemical characterisation techniques.Changes in coal surface hydrophobicity were assessed using contact angle measurements at the coal/water interface.The largest variation in zeta potential resulting from addition of surfactants was seen for the higher rank coals.The Specific surface area decreased when surfactants were present.

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 Dynamic Cell Surface Hydrophobicity of Lactobacillus Strains with and without Surface Layer Proteins

2004 ◽  
Vol 186 (19) ◽  
pp. 6647-6650 ◽  
Author(s):  
Virginia Vadillo-Rodríguez ◽  
Henk J. Busscher ◽  
Willem Norde ◽  
Joop de Vries ◽  
Henny C. van der Mei
Keyword(s):  
Ionic Strength ◽  
Cell Surface ◽  
Cell Surface Hydrophobicity ◽  
Interaction Force ◽  
Surface Hydrophobicity ◽  
Force Microscopy ◽  
Angle Measurements ◽  
Atomic Force ◽  
Contact Angle Measurements ◽  
Dynamic Cell

ABSTRACT Variations in surface hydrophobicity of six Lactobacillus strains with and without an S-layer upon changes in ionic strength are derived from contact angle measurements with low- and high-ionic-strength aqueous solutions. Cell surface hydrophobicity changed in response to changes in ionic strength in three out of the six strains, offering these strains a versatile mechanism to adhere to different surfaces. The dynamic behavior of the cell surface hydrophobicity could be confirmed for two selected strains by measuring the interaction force between hydrophobic and hydrophilic tips with use of atomic force microscopy.

Comparison of Molecular Monolayer Interface Treatments in Organic-inorganic Photovoltaic Devices

2009 ◽  
Vol 1154 ◽  
Author(s):  
Jamie M. Albin ◽  
Darick J. Baker ◽  
Cary G. Allen ◽  
Thomas E. Furtak ◽  
Reuben T. Collins ◽  
...  
Keyword(s):  
Photoelectron Spectroscopy ◽  
Molecular Layer ◽  
Sol Gel ◽  
Photovoltaic Devices ◽  
Water Contact ◽  
Angle Measurements ◽  
Contact Angle Measurements ◽  
Ir Transmission ◽  
Transmission Measurements ◽  
Molecular Layers

AbstractIn this study, we explore the effects of alkyl surface terminations on ZnO for inverted, planar ZnO/poly(3-hexylthiophene) (P3HT) solar cells using two different attachment chemistries. Octadecylthiol (ODT) and octadecyltriethoxysilane (OTES) molecules were used to create 18-carbon alkyl surface molecular layers on sol gel-derived ZnO surfaces. Molecular layer formation was confirmed and characterized using water contact angle measurements, infrared (IR) transmission measurements, and X-ray photoelectron spectroscopy (XPS). The performances of the ZnO/P3HT photovoltaic cells made from ODT- and OTES-functionalized ZnO were compared. The ODT-modified devices had higher efficiencies than OTES-modified devices, suggesting that differences in the attachment scheme affect the efficiency of charge transfer through the molecular layers at the treated ZnO surface.

Temperature Stability Of Plasma Polymerized Antiadhesive Coatings

1998 ◽  
Vol 544 ◽  
Author(s):  
W. Michaeli ◽  
R. Dahlmann ◽  
I. Fonteiner
Keyword(s):  
Surface Tension ◽  
Photoelectron Spectroscopy ◽  
Thermo Gravimetric Analysis ◽  
Temperature Stability ◽  
Polymer Coatings ◽  
Gravimetric Analysis ◽  
Angle Measurements ◽  
Wide Range ◽  
Contact Angle Measurements ◽  
Thermal Stability Of

AbstractBy means of microwave-assisted plasma polymerization it is possible to deposit polymer coatings on different surfaces such as plastics or metals. The surface tension can be influenced in a wide range. However, many applications require a high thermal stability of such low surface tension layers. Therefore, the influence of variations of the process parameters on temperature stability of such layers is examined. The produced layers were studied regarding their chemical and physical characteristics under temperature influence by means of contact angle measurements, xray photoelectron spectroscopy (XPS), thermo gravimetric analysis (TGA) combined with Fouriertransformed infrared spectroscopy (FTIR). Fluorine containing monomers offer good perspectives. Up to temperatures of approx. 200°C the antiadhesivity of these coatings is adjustable to values close to those of poly(tetrafluoroethylene) (PTFE).

scholarly journals Interface Characteristics and Anticorrosion Performances of Cold Galvanizing Coatings Incorporated with γ-chloropropyl Triethoxysilane on Hot-Dip Galvanized Steel

Coatings ◽  
2021 ◽  
Vol 11 (4) ◽  
pp. 402
Author(s):  
Jiwen Li ◽  
Qiumeng Wang ◽  
Ningjie Gao ◽  
Izuchukwu Kenneth Nwokolo ◽  
Wanyu Zhang ◽  
...  
Keyword(s):  
Photoelectron Spectroscopy ◽  
Large Scale ◽  
Galvanized Steel ◽  
Water Contact ◽  
Electrochemical Tests ◽  
Angle Measurements ◽  
Dry Adhesion ◽  
Interface Characteristics ◽  
Contact Angle Measurements ◽  
Poor Adhesion

The cold galvanizing coatings (CGCs) are used to repair old hot-dip galvanized steel (HDG) in numerous anticorrosion engineering, but poor adhesion of the CGC restricts its large-scale applications in the industries. For the purpose of overcoming the weak adhesion problems of the CGC on HDG, γ-chloropropyl triethoxysilane (CPTES) was added directly into cold galvanizing coatings (CPTES/CGC). Interface characteristics and related corrosion protection behaviors were investigated by the pull-off adhesion test, water contact angle measurements, Fourier transform infrared spectroscopy (FTIR), X-ray photoelectron spectroscopy (XPS), scanning electron microscope (SEM), and electrochemical tests. The experimental results revealed that, there is an increase by 19.1% of the CPTES/CGC surface free energy when compared with that of CGC. In addition, Si–O–Si and Si–O–Zn bonds were found in the CPTES/CGC, which indicate new network structures formed inside the CPTES/CGC, between the interface of the CPTES/CGC and HDG substrate, resulting in dry adhesion, wet adhesion, and the cathodic protection time of CPTES/CGC increased by 50% and 200% and 300% respectively compared with the CGC.

scholarly journals Evaluation of the Effect of the Microscopic Glass Surface Protonation on the Hard Tissue Thin Section Preparation

2020 ◽  
Vol 10 (21) ◽  
pp. 7742
Author(s):  
Melinda Szalóki ◽  
Viktória Hegedűs ◽  
Tamás Fodor ◽  
Renáta Martos ◽  
Tünde Radics ◽  
...  
Keyword(s):  
Photoelectron Spectroscopy ◽  
Glass Surface ◽  
Microscopic Analysis ◽  
Dihydrogen Phosphate ◽  
Bovine Bone ◽  
Angle Measurements ◽  
Contact Angle Measurements ◽  
Bone Section ◽  
Positively Charged ◽  
Frosted Glass

In this study, a new procedure for mounting tissue blocks was described while cutting and grinding the section remains tightly bound to the inert glass surface both chemically and micro mechanically allowing good quality specimens for staining and microscopic analysis. The micromechanical interlocking was achieved by using of frosted glass, the chemical binding was made with 10-methacryloyloxydecyl dihydrogen phosphate monomer (10-MDP) containing bond material. The glass surface activation was achieved by nitric acid etching and the surface was characterized by zeta potential, X-ray photoelectron spectroscopy (XPS), and contact angle measurements. Cylindrical samples were prepared from epoxy embedding materials, cortical bovine bone, and dental titanium to investigate the shear bond strengths (SBS) to microscopic glass slide compared to a routinely used thermoplastic adhesive. Based on the experiments it was found that the micromechanical retention combined with MDP containing bond material improved the SBS data compared to the thermoplastic adhesive. The acid etched glass became positively charged that significantly increased the SBS data of bone and titanium compared with the uncharged version. Therefore, the thickness of the undecalcified bone section with metal can safely reduce to improve histological microscopic analysis.

scholarly journals Polyhedral Oligomeric Silsesquioxane (POSS) Surface Grafting: A Novel Method to Enhance Polylactide Hydrolysis Resistance

Nanomaterials ◽  
2019 ◽  
Vol 9 (8) ◽  
pp. 1144 ◽  
Author(s):  
Li ◽  
Colonna ◽  
Fina ◽  
Monticelli
Keyword(s):  
Photoelectron Spectroscopy ◽  
Polymer Surface ◽  
Polyhedral Oligomeric Silsesquioxane ◽  
Film Surface ◽  
Surface Hydrophobicity ◽  
Homogeneous Distribution ◽  
Angle Measurements ◽  
The Stability ◽  
Hydrolysis Resistance ◽  
Oligomeric Silsesquioxane

Abstract: This work considers the development of an easy and scalable approach to change the features of poly(l-lactide) (PLLA) films, which is based on the application of a surface treatment with an amino-functionalized polyhedral oligomeric silsesquioxane (POSS). Indeed, the developed approach is based on the potential reactivity of POSS amino group towards the polymer functionalities to produce an aminolysis reaction, which should promote the direct grafting of the silsesquioxane molecules on the polymer surface. Neat and treated films were studied by infrared spectroscopy and X-ray photoelectron spectroscopy, which proved the effectiveness of POSS grafting. Moreover, scanning electron microscopy measurements demonstrated the homogeneous distribution of Si on the film surface treated with the silsesquioxane. The influence of the film treatment on the surface wettability was evidenced by contact angle measurements. These findings demonstrated a relevant enhancement of the surface hydrophobicity, which increase turned out to depend on the conditions applied, as it increased by increasing the reaction temperature and the contact time. Finally, in order to evaluate the stability of neat and of the treated PLLA films the surface morphology of the samples treated with pH 7.4 buffer at 50 °C was studied.

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.

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