scholarly journals Effects of Galvanic Interaction between Chalcopyrite and Monoclinic Pyrrhotite on Their Flotation Separation

Minerals ◽  
2021 ◽  
Vol 12 (1) ◽  
pp. 39
Author(s):  
Liu Yang ◽  
Xiaowen Zhou ◽  
Huashan Yan ◽  
Hongliang Zhang ◽  
Xiaohe Liu ◽  
...  
Keyword(s):  
Photoelectron Spectroscopy ◽  
The Other ◽  
X Ray ◽  
Flotation Recovery ◽  
Xps Characterization ◽  
Monoclinic Pyrrhotite ◽  
Galvanic Interaction ◽  
Monomineral Flotation ◽  
Sem Test ◽  
Scanning Electron

The galvanic interaction between chalcopyrite and monoclinic pyrrhotite and its effect on flotation separation were studied using monomineral flotation tests, adsorption capacity tests, X-ray photoelectron spectroscopy (XPS) characterization, and scanning electron microscopy (SEM) test. These results showed that the interaction promoted the reduction of O2 on the cathodic chalcopyrite surface and accelerated the generation of Fe(OH)3, which was not conducive to collector adsorption; hence, the flotation recovery decreased by 10–16%. On the other hand, galvanic interaction accelerated the oxidation of S on the anodic monoclinic pyrrhotite surface to S0 or SO42− and produced a large amount of H+, thus preventing the formation of Fe(OH)3. Meanwhile, the Cu2+ eluted from chalcopyrite surface activated monoclinic pyrrhotite; hence, the flotation recovery increased by 3–10%. Galvanic interaction reduced the floatability difference between the two minerals, and the separation difficulty was significantly increased. Even with an increase in the amount of lime, the separation could not be improved.

scholarly journals SEM imaging and XPS characterization of doped PVDF fibers

2021 ◽  
Vol 270 ◽  
pp. 01011
Author(s):  
Tereza Smejkalová ◽  
Ştefan Ţălu ◽  
Rashid Dallaev ◽  
Klára Částková ◽  
Dinara Sobola ◽  
...  
Keyword(s):  
Electron Microscope ◽  
Scanning Electron Microscope ◽  
Photoelectron Spectroscopy ◽  
Analytical Methods ◽  
Polyvinylidene Fluoride ◽  
X Ray ◽  
Xps Characterization ◽  
Good Biocompatibility ◽  
The Individual ◽  
Scanning Electron

Polyvinylidene fluoride (PVDF) is one of the most promising electroactive polymers; it exhibits excellent electroactive behaviours, good biocompatibility, excellent chemical resistance, and thermal stability, rendering it an attractive material for biomedical, electronic, environmental and energy harvesting applications. This work aims to further improve its properties by the inclusion of powders of piezoactive materials. Polyvinylidene fluoride was formed by electrospinning into fibres with a thickness of 1.5-0.3 µm and then examined in a scanning electron microscope. The work offers a description of the current procedure in the preparation of samples and their modification for examination in a scanning electron microscope, characterizes the individual components of doped fibres and deals with specific instruments used for various analytical methods. The work contains a theoretical introduction to the analytical methods to which the samples will be further subjected, such as energy dispersive X-ray spectroscopy (EDX), X-ray photoelectron spectroscopy (XPS). The obtained excellent properties of doped PVDF could be used in the design of sensors.

Hypochlorous and Urea Modifications on Carbon Fiber Surface and Effects on Microorganism Immobilization

2011 ◽  
Vol 356-360 ◽  
pp. 106-109 ◽  
Author(s):  
Yan Ling Bao ◽  
Guang Ze Dai ◽  
Chuan Jiang
Keyword(s):  
Electron Microscope ◽  
Carbon Fiber ◽  
Scanning Electron Microscope ◽  
Surface Morphology ◽  
Photoelectron Spectroscopy ◽  
Fiber Surface ◽  
The Other ◽  
X Ray ◽  
Microorganism Immobilization ◽  
Scanning Electron

PAN-based carbon fiber (CF) was modified by hypochlorous and urea in current treatments. The CF surface morphology and natures were characterized by specific facilities, such as scanning electron microscope (SEM), X-ray photoelectron spectroscopy (XPS) and the degree of moisture. On the other hand, the biocompatibility nature was indicated by immobilization results of microorganisms on CF. The results show that the surface hydrophilicity and roughness of CF surface would contribute greatly to improve the immobilization ability of microorganisms on CF surface, and the produced oxygen on CF has more effect on microorganism immobilization than nitrogen.

scholarly journals Investigation of Spin Coating Cerium-Doped Hydroxyapatite Thin Films with Antifungal Properties

Coatings ◽  
2021 ◽  
Vol 11 (4) ◽  
pp. 464
Author(s):  
Simona Liliana Iconaru ◽  
Mihai Valentin Predoi ◽  
Patrick Chapon ◽  
Sofia Gaiaschi ◽  
Krzysztof Rokosz ◽  
...  
Keyword(s):  
Electron Microscopy ◽  
Scanning Electron Microscopy ◽  
Photoelectron Spectroscopy ◽  
Spin Coating ◽  
Laser Scanning ◽  
Laser Scanning Microscopy ◽  
Confocal Laser ◽  
X Ray ◽  
Antifungal Properties ◽  
Scanning Electron

In this study, the cerium-doped hydroxyapatite (Ca10−xCex(PO4)6(OH)2 with xCe = 0.1, 10Ce-HAp) coatings obtained by the spin coating method were presented for the first time. The stability of the 10Ce-HAp suspension particles used in the preparation of coatings was evaluated by ultrasonic studies, transmission electron microscopy (TEM), X-ray diffraction (XRD), and scanning electron microscopy (SEM). The surface morphology of the 10Ce-HAp coating was studied by SEM and atomic force microscopy (AFM) techniques. The obtained 10Ce-HAp coatings were uniform and without cracks or unevenness. Glow discharge optical emission spectroscopy (GDOES) and X-ray photoelectron spectroscopy (XPS) were used for the investigation of fine chemical depth profiling. The antifungal properties of the HAp and 10Ce-HAp suspensions and coatings were assessed using Candida albicans ATCC 10231 (C. albicans) fungal strain. The quantitative antifungal assays demonstrated that both 10Ce-HAp suspensions and coatings exhibited strong antifungal properties and that they successfully inhibited the development and adherence of C. albicans fungal cells for all the tested time intervals. The scanning electron microscopy (SEM) and confocal laser scanning microscopy (CLSM) visualization of the C. albicans fungal cells adherence to the 10Ce-HAp surface also demonstrated their strong inhibitory effects. In addition, the qualitative assays also suggested that the 10Ce-HAp coatings successfully stopped the biofilm formation.

scholarly journals Improvement of the thermal stability of dendritic silver-coated copper microparticles by surface modification based on molecular self-assembly

2021 ◽  
Vol 8 (1) ◽  
Author(s):  
Tae Hyeong Kim ◽  
Hyeji Kim ◽  
Hyo Jun Jang ◽  
Nara Lee ◽  
Kwang Hyun Nam ◽  
...  
Keyword(s):  
Thermal Stability ◽  
Photoelectron Spectroscopy ◽  
Self Assembly ◽  
Electrically Conductive ◽  
X Ray ◽  
Alkyl Chains ◽  
Conductive Film ◽  
Initial Resistance ◽  
Thermal Stability Of ◽  
Scanning Electron

AbstractIn the study reported herein, silver-coated copper (Ag/Cu) powder was modified with alkanethiols featuring alkyl chains of different lengths, namely butyl, octyl, and dodecyl, to improve its thermal stability. The modification of the Ag/Cu powders with adsorbed alkanethiols was confirmed by scanning electron microscopy with energy dispersive spectroscopy, X-ray photoelectron spectroscopy, and thermogravimetric analysis. Each powder was combined with an epoxy resin to prepare an electrically conductive film. The results confirmed that the thermal stability of the films containing alkanethiol-modified Ag/Cu powders is superior to that of the film containing untreated Ag/Cu powder. The longer the alkyl group in the alkanethiol-modified Ag/Cu powder, the higher the initial resistance of the corresponding electrically conductive film and the lower the increase in resistance induced by heat treatment.

Preparation of Carbon Nanofibers from Polyacrylonitrile Nanofibers by Electrospinning

2011 ◽  
Vol 415-417 ◽  
pp. 642-647
Author(s):  
En Zhong Li ◽  
Da Xiang Yang ◽  
Wei Ling Guo ◽  
Hai Dou Wang ◽  
Bin Shi Xu
Keyword(s):  
Electron Microscope ◽  
Carbon Nanofibers ◽  
Photoelectron Spectroscopy ◽  
Solution Concentration ◽  
Dimethyl Formamide ◽  
Ultrafine Fibers ◽  
X Ray ◽  
Scanning Electron ◽  
Pan Fibers

Ultrafine fibers were electrospun from polyacrylonitrile (PAN)/N,N-dimethyl formamide (DMF) solution as a precursor of carbon nanofibers. The effects of solution concentration, applied voltage and flow rate on preparation and morphologies of electrospun PAN fibers were investigated. Morphologies of the green fibers, stabilized fibers and carbonized fibers were compared by scanning electron microscope (SEM). The diameter of PAN nanofibers is about 450nm and the distribution of diameter is well-proportioned. Characterization of the elements changes of fibers were performed by X-ray photoelectron spectroscopy (XPS).

ROOM TEMPERATURE PHOTOLUMINESCENCE OF POLYCRYSTALLINE SIC PREPARED FROM CARBON-SATURATED SI MELT

2002 ◽  
Vol 16 (06n07) ◽  
pp. 1047-1051
Author(s):  
JIANPING MA ◽  
ZHIMING CHEN ◽  
GANG LU ◽  
MINGBIN YU ◽  
LIANMAO HANG ◽  
...  
Keyword(s):  
Electron Microscopy ◽  
Photoelectron Spectroscopy ◽  
Room Temperature ◽  
Uv Light ◽  
X Ray Diffraction ◽  
X Ray ◽  
Room Temperature Photoluminescence ◽  
Composition And Structure ◽  
Light Excitation ◽  
Scanning Electron

Intense photoluminescence (PL) has been observed at room temperature from the polycrystalline SiC samples prepared from carbon-saturated Si melt at a temperature ranging from 1500 to 1650°C. Composition and structure of the samples have been confirmed by means of X-ray photoelectron spectroscopy, X-ray diffraction and scanning electron microscopy. PL measurements with 325 nm UV light excitation revealed that the room temperature PL spectrum of the samples consists of 3 luminescent bands, the peak energies of which are 2.38 eV, 2.77 eV and 3.06 eV, respectively. The 2.38 eV band is much stronger than the others. It is suggested that some extrinsic PL mechanisms associated with defect or interface states would be responsible to the intensive PL observed at room temperature.

Preparation of Graphene/MoS2 Composite for Detection of Dopamine

2022 ◽  
Vol 905 ◽  
pp. 192-197
Author(s):  
Lin Lin Cai ◽  
Xiao Qing Jiang
Keyword(s):  
Raman Spectra ◽  
Photoelectron Spectroscopy ◽  
The Other ◽  
Organic Salt ◽  
Carbon Electrode ◽  
Sodium Tartrate ◽  
X Ray ◽  
Transmission Electron ◽  
Linear Detection ◽  
Potassium Sodium Tartrate

A new composite of graphene/MoS2 is synthesized by co-exfoliation of graphite and MoS2 in isopropanol (IPA) using the organic salt potassium sodium tartrate as the assistant. The composite is characterized by transmission electron microscopy (TEM), X-ray photoelectron spectroscopy (XPS), and Raman spectra. The results of TEM, XPS, and Raman spectra all illustrate that the graphene/MoS2 composite has been synthesized successfully. Furthermore, the composite is modified on glassy carbon electrode to fabricate a sensor to detect dopamine (DA). The sensor shows two linear detection ranges for DA. One is 1-45 μM and the other is 45-120 μΜ. The detection limit of the sensor (S/N=3) is 0.76 μM.

Growth of SiOx Nanowires by Simple Vapor Transport Method and their Optical Properties

2013 ◽  
Vol 534 ◽  
pp. 141-145 ◽  
Author(s):  
Yuto Hakamada ◽  
Shunji Ozaki
Keyword(s):  
Electron Microscopy ◽  
Photoelectron Spectroscopy ◽  
Silicon Monoxide ◽  
Vapor Transport ◽  
X Ray ◽  
Si Substrates ◽  
Vls Growth ◽  
Transport Method ◽  
Vapor Transport Method ◽  
Scanning Electron

SiOx nanowires were grown on Si substrates by a simple vapor transport method of heating the mixture of silicon monoxide and carbon powders at 1000 °C in a tube of the furnace. The dependence of the growth velocity on the growth temperature and on the radius of nanowires indicates that the SiOx nanowires grow through the vaporliquidsolid (VLS) growth mechanism. The properties of the nanowires are characterized using scanning electron microscopy (SEM), X-ray photoelectron spectroscopy (XPS), and photoluminescence (PL).

scholarly journals Effect of Surfactant Addition on Bi2Te3 Nanostructures Synthesized by Hydrothermal Method

2017 ◽  
Vol 62 (2) ◽  
pp. 1005-1010 ◽  
Author(s):  
Peyala Dharmaiah ◽  
C.H. Lee ◽  
B. Madavali ◽  
Soon-Jik Hong
Keyword(s):  
Electron Microscopy ◽  
Hydrothermal Method ◽  
Figure Of Merit ◽  
Bulk Sample ◽  
The Other ◽  
X Ray Diffraction ◽  
X Ray ◽  
Coarse Grains ◽  
Scanning Electron ◽  
Nanostructured Sample

AbstractIn the present work, we have prepared Bi2Te3nanostructures with different morphologies such as nano-spherical, nanoplates and nanoflakes obtained using various surfactant additions (EG, PVP, and EDTA) by a hydrothermal method. The shape of the nanoparticles can be controlled by addition of surfactants. The samples were characterized by x-ray diffraction (XRD) and scanning electron microscopy (SEM). It is found that the minority BiOCl phase disappears after maintained pH at 10 with EG as surfactant. SEM bulk microstructure reveals that the sample consists of fine and coarse grains. Temperature dependence of thermoelectric properties of the nanostructured bulk sample was investigated in the range of 300-450K. The presence of nanograins in the bulk sample exhibits a reduction of thermal conductivity and less effect on electrical conductivity. As a result, a figure of merit of the sintered bulk sample reached 0.2 at 400 K. A maximum micro Vickers hardness of 102 Hv was obtained for the nanostructured sample, which was higher than the other reported results.

scholarly journals Facile preparation of α-Fe2O3 nanobulk via bubble electrospinning and thermal treatment

2016 ◽  
Vol 20 (3) ◽  
pp. 967-972 ◽  
Author(s):  
Peng Liu ◽  
Chun-Hui He ◽  
Fujuan Liu ◽  
Lan Xu ◽  
Yuqin Wan ◽  
...  
Keyword(s):  
Fourier Transform ◽  
Photoelectron Spectroscopy ◽  
Polyvinylidene Fluoride ◽  
Iron Chloride ◽  
Electrospinning Technique ◽  
Broad Application ◽  
X Ray ◽  
Chloride Hexahydrate ◽  
Facile Preparation ◽  
Scanning Electron

In this work, ?-Fe2O3 nanobulk with high aspect ratio were successfully prepared via a facile bubble electrospinning technique using polyvinylidene fluoride and iron chloride hexahydrate (FeCl3?6H2O) as ?-Fe2O3 precursor followed by annealing in air at 600?C. The products were characterized with field emission scanning electron microscope, Fourier transform infrared, X-ray photoelectron spectroscopy, and thermogravimetric analysis. The results showed that ?-Fe2O3 nanobulk has a hierarchical heterostructure which has an extremely broad application prospect in many areas.

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