Raman and X-ray Photoemission Identification of Colloidal Metal Sulfides as Potential Secondary Phases in Nanocrystalline Cu2ZnSnS4 Photovoltaic Absorbers

2020 ◽  
Vol 3 (6) ◽  
pp. 5706-5717
Author(s):  
Oleksandr Selyshchev ◽  
Yevhenii Havryliuk ◽  
Mykhailo Ya. Valakh ◽  
Volodymyr O. Yukhymchuk ◽  
Oleksandra Raievska ◽  
...  
TAPPI Journal ◽  
2011 ◽  
Vol 10 (1) ◽  
pp. 17-23
Author(s):  
KEVIN TAYLOR ◽  
RICH ADDERLY ◽  
GAVIN BAXTER

Over time, performance of tubular backpulse pressure filters in kraft mills deteriorates, even with regular acid washing. Unscheduled filter replacement due to filter plugging results in significant costs and may result in mill downtime. We identified acid-insoluble filter-plugging materials by scanning electron microscope/energy-dispersion X-ray spectroscopy (SEM/EDS) and X-ray diffraction (XRD) analysis in both polypropylene and Gore-Tex™ membrane filter socks. The major filter-plugging components were calcium sulfate (gypsum), calcium phosphate (hydroxylapatite), aluminosilicate clays, metal sulfides, and carbon. We carried out detailed sample analysis of both the standard acid-washing procedure and a modified procedure. Filter plugging by gypsum and metal sulfides appeared to occur because of the acid-washing procedure. Gypsum formation on the filter resulted from significant hydrolysis of sulfamic acid solution at temperatures greater than 130°F. Modification of the acid-washing procedure greatly reduced the amount of gypsum and addition of a surfactant to the acid reduced wash time and mobilized some of the carbon from the filter. With surfactant, acid washing was 95% complete after 40 min.


Molecules ◽  
2021 ◽  
Vol 26 (15) ◽  
pp. 4676
Author(s):  
Jorge Luis Costafreda ◽  
Domingo Alfonso Martín

This work describes the newly discovered zeolites in the eastern region of Cuba. In the researched area, there have been no previous studies of natural zeolite exploration. Therefore, the results shown here are new. The main object of this research is to analyse five samples of zeolites and demonstrate their pozzolanic capacity and the possibility of their usage in the industrial manufacturing of pozzolanic cements. The study of the samples was performed by X-ray diffraction (XRD), X-ray fluorescence (XRF) and scanning electron microscopy (SEM). A chemical analysis (CAQ) to determine the quality of the samples as pozzolans was performed, by determining the total SiO2, reactive SiO2, total CaO, reactive CaO, Al2O3, MgO and the insoluble residue (I.R.). Lastly, an eight-day pozzolanicity analysis (PA) was carried out to determine the pozzolanic reactivity of the samples. The results obtained by XRD, XRF and SEM established that the researched zeolite samples have two main zeolitic phases: mordenite and clinoptilolite. Altered volcanic glass, quartz and smectite (montmorillonite) are the secondary phases. The results of the chemical quality analysis (CAQ) showed that the samples contain a considerable amount of reactive SiO2 and reactive CaO, as well as a low content of insoluble residue, which reinforces their properties as pozzolans. The results of the pozzolanicity analysis (PA) concluded that the analysed samples actively react with Ca(OH)2 after eight days. Based on all the results mentioned above, it is established that both mordenite and clinoptilolite behave like pozzolans and can be recommended for the manufacture of pozzolanic cements, which have more effective properties than Portland cement, in terms of physical, chemical and mechanical strength, low heat of hydration, resistance to sulphates, low CO2 emissions to the atmosphere and negligible impacts on the environment.


2013 ◽  
Vol 212 ◽  
pp. 15-20
Author(s):  
Kazimierz J. Ducki ◽  
Jacek Mendala ◽  
Lilianna Wojtynek

The influence of prolonged ageing on the precipitation process of the secondary phases in an Fe-Ni superalloy of A-286 type has been studied. The samples were subjected to a solution heat treatment at 980°C for 2 h and water quenched, and then aged at temperatures of 715, 750 and 780°C at holding times from 0.5 to 500 h. Structural investigations were conducted using TEM and X-ray diffraction methods. The X-ray phase analyses performed on the isolates were obtained by anodic dissolution of the solid samples. After solution heat treatment the alloy has the structure of twinned austenite with a small amount of undissolved precipitates, such as carbide TiC, carbonitride TiC0.3N0.7, nitride TiN0.3, carbosulfide Ti4C2S2, Laves phase Ni2Si, and boride MoB. The application of ageing causes precipitation processes of γ-Ni3(Al,Ti), G (Ni16Ti6Si7), η (Ni3Ti), β (NiTi) and σ (Cr0.46Mo0.40Si0.14) intermetallic phases, as well as the carbide M23C6. It was found that the main phase precipitating during alloy ageing was the γ intermetallic phase.


2021 ◽  
pp. 110010
Author(s):  
Chi Zhang ◽  
Chen Liu ◽  
Xin Li ◽  
Keli Liu ◽  
Guangyuan Tian ◽  
...  

1992 ◽  
Vol 45 (20) ◽  
pp. 12043-12049 ◽  
Author(s):  
D. R. Warburton ◽  
D. Purdie ◽  
C. A. Muryn ◽  
N. S. Prakash ◽  
K. Prabhakaran ◽  
...  

2001 ◽  
Vol 695 ◽  
Author(s):  
M.J. Daniels ◽  
D. King ◽  
J.S. Zabinski ◽  
Z.U. Rek ◽  
J.C. Bilello

ABSTRACTQuasicrystalline films were formed by RF sputtering from a powder composite target onto Inconel substrates, which produces a polymorphic nanoquasicrystalline grain structure, ~2.5 - 10 nm. Subsequent annealing at 500°C for 4 hours, at base pressures of below 5*10-5 Torr, and with Ar flow to 5 - 10 mT, fully develops the quasicrystalline structure with decagonal phase predominating, except near the termination surface. Analysis by XPS indicated extensive oxygen incorporation and limited aluminum enrichment at the termination surface. These results are correlated with structure and strain analysis via synchrotron grazing incidence x-ray scattering (GIXS). By varying the incident angle, hence the x-ray penetration depth, the evolution of an amorphous and crystalline crystalline secondary phases at the surface of the film has been detected. Residual strain analysis shows that this second phase induces a compressive residual strain of 0.10% as measured from the displacement of the major quasicrystalline peaks in the surface layers of the film.


MRS Advances ◽  
2016 ◽  
Vol 2 (10) ◽  
pp. 557-562 ◽  
Author(s):  
D.J. Bailey ◽  
M.C. Stennett ◽  
N.C. Hyatt

ABSTRACTDue to their high actinide content MOX residues require immobilization within a robust host matrix. Although it is possible to immobilize actinides in vitreous wasteforms; ceramic phases, such as brannerite (UTi2O6), are attractive due to their high waste loading capacity and relative insolubility. Brannerites Gd0.1U0.9Ti2O6, Ce0.1U0.9Ti2O6and Gd0.1U0.81Ce0.09Ti2O6were prepared using an oxide route. Charge compensation of trivalent cations was expected to occur via the oxidation of U (IV) to higher valence states (U (V) or U (VI)). Gd was added to act as a neutron absorber in the final Pu bearing wasteform and Ce was used as a structural surrogate for Pu. X-ray absorption spectroscopy showed that Ce (IV) was reduced to Ce (III) in all cases. X-ray powder diffraction of synthesized specimens found that the final phase assemblage was strongly affected by processing atmosphere (air or argon). Prototypical brannerite was formed in all compositions, secondary phases observed were found to vary according to processing atmosphere and stoichiometry. Microstructural analysis (SEM) of the sintered samples confirmed the results of the X-ray powder diffraction.


2019 ◽  
Vol 54 (1) ◽  
Author(s):  
Francisco Méndez-Martínez ◽  
Federico González ◽  
Enrique Lima ◽  
Pedro Bosch ◽  
Heriberto Pfeiffer

This work presents the structural characterization and electrical evaluation of Znx-1CuxMn2O4 spinels, which are materials presented as secondary phases into the varistor ceramic systems. Samples were analyzed by X-ray diffraction, solid-state nuclear magnetic resonance, infrared spectroscopy, scanning electron microscopy and impedance spectroscopy. Although, the addition of copper to the ZnMn2O4 spinel did not produce morphological changes, the structure and electrical behaviors changed considerably. Structurally, copper addition induced the formation of partial inverse spinels, and its addition increases significantly the electrical conductivity. Therefore, the formation of Znx-1CuxMn2O4 spinels, as secondary phases into the varistor materials, may compromise significantly the varistor efficiency.   Ceramic, Impedance Spectroscopy, spinel, Varistor, XRD.


2020 ◽  
Vol 989 ◽  
pp. 577-582
Author(s):  
I.E. Illarionov ◽  
T.R. Gilmanshina ◽  
A.A. Kovaleva

The purpose of this work is to study the structure and mechanical properties of an aluminum – magnesium system alloy after various types of heat treatment (quenching and ageing). The microstructure of an alloy has been studied by means of Zeiss OBSERVER.D1m microscope combined with a camera and image display on a monitor screen. Micro X-ray spectral analysis was performed by means of Carl Zeiss EVO 50 scanning electron microscope. The micro-hardness of the samples has been measured on prepared metallographic sections by means of DM8 micro-hardness meter. In the course of the process it has been found that quenching the Al-12,78% Mg alloy from temperatures of 430–440 ° C does not lead to the formation of a single-phase solid solution. Ageing at 100 ° C enables the formation of secondary phases. It was noted that with an increase in the quenching temperature, the micro-hardness increases slightly. An increase in the exposure time doesn’t influence greatly the micro-hardness of the alloy, while the structure remains practically unchanged.


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