Effects of Etching on Zircon Grains and its Implications for the Fission Track Method

2012 ◽  
Vol 66 (5) ◽  
pp. 545-551 ◽  
Author(s):  
Carlos Alberto Tello Sáenz ◽  
Eduardo Augusto Campos Curvo ◽  
Airton Natanael Coelho Dias ◽  
Cleber José Soares ◽  
Carlos José Leopoldo Constantino ◽  
...  
Keyword(s):  
Chemical Composition ◽  
Crystal Lattice ◽  
Fission Track ◽  
Surface Characteristics ◽  
Optical Microscope ◽  
Etching Time ◽  
X Ray ◽  
Track Method ◽  
Zircon Fission Track ◽  
Natural Zircon

Studies of zircon grains using optical microscopy, micro-Raman spectroscopy, and scanning electron microscopy (SEM) have been carried out to characterize the surface of natural zircon as a function of etching time. According to the surface characteristics observed using an optical microscope after etching, the zircon grains were classified as: (i) homogeneous; (ii) anomalous, and (iii) hybrid. Micro-Raman results showed that, as etching time increases, the crystal lattice is slightly altered for homogeneous grains, it is completely damaged for anomalous grains, and it is altered in some areas for hybrid grains. The SEM (energy dispersive X-ray spectroscopy, EDS) results indicated that, independent of the grain types, where the crystallinity remains after etching, the chemical composition of zircon is approximately 33% SiO2:65% ZrO2 (standard natural zircon), and for areas where the grain does not have a crystalline structure, there are variations of ZrO2 and, mainly, SiO2. In addition, it is possible to observe a uniform surface density of fission tracks in grain areas where the determined crystal lattice and chemical composition are those of zircon. Regarding hybrid grains, we discuss whether the areas slightly altered by the chemical etching can be analyzed by the fission track method (FTM) or not. Results of zircon fission track and U-Pb dating show that hybrid and homogeneous grains can be used for dating, and not only homogeneous grains. More than 50 sedimentary samples from the Bauru Basin (southeast Brazil) were analyzed and show that only a small amount of grains are homogeneous (10%), questioning the validity of the rest of the grains for thermo-chronological evolution studies using zircon FTM dating.

The Basic Characteristics of Gasification Slag from Texaco Gasifier and Shell Gasifier

2014 ◽  
Vol 675-677 ◽  
pp. 728-732 ◽  
Author(s):  
Hu Die Yuan ◽  
Hong Feng Yin ◽  
Yun Tang ◽  
Hang Shuai
Keyword(s):  
Chemical Composition ◽  
Optical Microscope ◽  
Residual Carbon ◽  
X Ray Diffraction ◽  
Laminar Structure ◽  
X Ray ◽  
Main Chemical Composition ◽  
Basic Characteristics ◽  
Molten Liquid ◽  
Structure And Microstructure

Gasification slag is one of the solid wastes forming by water-granulation for molten liquid and residual carbon. In this paper, the basic characteristics of gasification slags from Texaco and Shell gasifier (termed as WH and QP, respectively) were studied. X-ray fluorescence (XRF), X-ray diffraction (XRD), optical microscope (OM), and scanning electron microscopy (SEM) were carried to investigate the chemical composition, phase constituents, petrographical structure and microstructure of the slag, respectively. The results showed that: (1) The main chemical composition of WH and QP is SiO2, Al2O3and CaO. In addition, a large amount of residual carbon is also existed in WH. (2) The main phases of WH and QP are vitreous glass and quartz. In addition, calcite is also detected in WH; (3) The microstructural features of the two slags are nearly the same. Residual carbon in WH is existed with laminar structure.

Micro-Raman spectroscopy and SEM/EDX applied to improve the zircon fission track method used for dating geological formations

2009 ◽  
Vol 40 (1) ◽  
pp. 101-106 ◽  
Author(s):  
Airton Natanael Coelho Dias ◽  
Carlos Alberto Tello Saenz ◽  
Carlos José Leopoldo Constantino ◽  
Cleber José Soares ◽  
Felipe Ponciano Novaes ◽  
...  
Keyword(s):  
Raman Spectroscopy ◽  
Fission Track ◽  
Micro Raman Spectroscopy ◽  
Track Method ◽  
Zircon Fission Track ◽  
Geological Formations

Nanotube Morphology Changes of Ti–xTa–Ag–Pt Alloys with Ta Content for Biomaterials

2021 ◽  
Vol 21 (9) ◽  
pp. 4807-4812
Author(s):  
Hye-Ri Cho ◽  
Han-Cheol Choe
Keyword(s):  
Melting Furnace ◽  
Surface Characteristics ◽  
Optical Microscope ◽  
Vacuum Arc ◽  
Image Analyzer ◽  
X Ray ◽  
Heat Treated ◽  
Pt Alloy ◽  
Pt Alloys ◽  
Morphology Changes

In this study, nanotube morphology changes of Ti–xTa–Ag–Pt alloys with Ta content for biomaterials were researched using various experimental instruments. Ti–xTa–Ag–Pt alloys were manufactured in an Ar atmosphere using a vacuum arc-melting furnace with Ta contents of 10 and 50, and then heat-treated at 1100 °C for 1 hr. Nanotube formation of Ti–xTa–Ag–Pt (x = 10, 50 wt%) alloys were performed using a DC power of 30 V in 1.0 M H3PO4 + 0.8 wt% NaF electrolyte solution. Surface characteristics were investigated using an optical microscope, X-ray diffractometer, field-emission scanning electron microscope, energy-dispersive X-ray spectroscopy, and Image analyzer (Image J). Ti–10Ta–Ag–Pt alloy had a needle-like structures, and Ti–Ti–50Ta–Ag–Pt showed the mixed structure (equiaxed and needle-like structures). As the Ta content increased, the α-phase decreased and the β-phase increased. The highly ordered nanotubes were formed on the β-phase, whereas disordered nanotubes were formed on needle-like structure of α-phase in Ti–10Ta–Ag–Pt alloy. As the Ta content increases, large and small nanotube diameters became smaller in size. Anatase and rutile phases were formed on the alloy surface. Ta, Ag, and Pt elements were uniformly distributed over the entire surface and at the edge or inside of the nanotube.

scholarly journals A Review of Glass Fibre Recycling Technology Using Chemical and Mechanical Separation of Surface Sizing Agents

Recycling ◽  
2021 ◽  
Vol 6 (4) ◽  
pp. 79
Author(s):  
Jih-Hsing Chang ◽  
Ya-Shiuan Tsai ◽  
Pei-Yu Yang
Keyword(s):  
Glass Fiber ◽  
Organic Solvents ◽  
Environmental Concern ◽  
Raw Materials ◽  
Fine Powder ◽  
Surface Characteristics ◽  
Optical Microscope ◽  
Industrial Applications ◽  
X Ray ◽  
Surface Sizing

Glass fiber is widely used in various modern industrial applications because it has the advantages of good electrical insulation performance and good process ability. Inevitably, some flawed glass fiber generated during manufacturing processes becomes waste and, in recent years, the treatment or recycling of glass fiber waste has become an environmental concern. Since glass fiber is brittle, non-wearing, and can easily generate static electricity after friction, the surface of glass fiber must be coated with a wetting agent (i.e., surface sizing agent) to overcome these disadvantages. However, glass fiber waste cannot be directly recycled as glass raw materials due to the presence of the surface sizing agent and the high content of sodium element. Therefore, there is a need to develop a feasible technology for removal of surface sizing agent in order to recycle glass fiber waste. In this study, two methods were used to remove surface sizing agent from glass fiber waste. After removing the surface sizing agent, the treated glass fiber waste can replace sand particles for manufacturing controlled low-strength material (CLSM). The first method for removing surface sizing agent used different organic solvents such as ethyl acetate to dissolve the surface coating (i.e., surface sizing agent). Then, an optical microscope was used to observe the surface changes before and after such removal treatments. The second method involved grinding glass fiber waste into a fine powder and heating it to a high temperature. An X-ray diffractometer (XRD) and X-ray fluorescence (XRF) were used to analyze the surface characteristics of the glass fiber waste. The experimental results showed that different organic solvents could not effectively remove the surface sizing agent, even if the glass fiber waste was processed by ultrasonic vibration for 5 h. In contrast, after high heating at 800 °C for 2 h, the surface sizing agent could be removed, and glass fiber waste transformed to cristobalite. The CLSM concrete produced by mixing cristobalite with cement in an appropriate proportion can meet the CLSM specification standard in Taiwan.

scholarly journals Dating pseudotachylyte of the Nojima fault using the zircon fission-track method

2004 ◽  
Vol 31 (12) ◽  
pp. n/a-n/a ◽  
Author(s):  
Masaki Murakami ◽  
Takahiro Tagami
Keyword(s):  
Fission Track ◽  
Track Method ◽  
Zircon Fission Track ◽  
Nojima Fault

scholarly journals Synthesis and Structure of Ceramics of Bisubstituted M-Type Hexaferrite BaFe(11.5-x)Ti0.5AlxO19

2020 ◽  
Vol 12 (4) ◽  
pp. 110-119
Author(s):  
I. Solizoda ◽  
◽  
V. Zhivulin ◽  
D. Sherstyuk ◽  
A. Starikov ◽  
...  
Keyword(s):  
Electron Microscopy ◽  
Chemical Composition ◽  
Physical Properties ◽  
Crystal Lattice ◽  
High Frequency ◽  
Solid Phase ◽  
Functional Materials ◽  
Fine Tuning ◽  
Hexagonal Ferrites ◽  
X Ray

The development of scientific and technological progress is impossible without the creation of new functional materials. One of the classes of such materials are hexagonal ferrites. Their unique physical properties make them an irreplaceable material for the production of high-frequency electronics. The widespread introduction of high-frequency electronics into everyday life, over the past decade, has generated great interest in hexagonal ferrites. The number of publications devoted to the synthesis of mono- and bisubstituted ferrites noticeably increases every year. Modification of the chemical composition of a ferrite by replacing some of the iron atoms with another element, without changing its structure, leads to a change in physical properties of the material. Variation of the final ferrite properties, by changing its chemical composition, is of interest and is promising for fine tuning the material properties for a specific task. The aim of the present work is to experimentally study the possibility of synthesizing ferrite with a magnetoplumbite structure, in which the iron atoms are partially replaced by the Al and Ti atoms. A review of the scientific literature on this issue showed the absence of publications on ferrites with such a set of substitute elements. The X-ray phase and structural analysis, electron microscopy, and energy-dispersive X-ray spectroscopy were used as research methods in the present study. The article offers the results of an experimental study of the possibility of obtaining bisubstituted M-type ferrite of the BaFe(11.5-x)Ti0.5AlxO19 composition, where x (Al) = 0.1, 0.5, 1. Solid-phase synthesis has been used as a method for preparing samples. This method is devoid of technological difficulties and is promising from the point of view of its scaling for the synthesis of ferrite. The samples have been sintered at three different temperatures: 1300, 1350, and 1400 °C. It is shown that in the temperature range 1300–1400 ° C the formation of monophase samples occurs. The calculation of the parameters of the crystal lattice has been made. The influence of temperature and concentration of a substituting element on the change in the parameters of the crystal lattice of the material has been revealed. The study by the electron microscopy method made it possible to reveal the presence of latent microporosity of the samples.

Photocatalytic activity of TiO2 synthesized by anodization and anodic spark deposition

MRS Advances ◽  
2020 ◽  
Vol 5 (61) ◽  
pp. 3141-3152
Author(s):  
Alma C. Chávez-Mejía ◽  
Génesis Villegas-Suárez ◽  
Paloma I. Zaragoza-Sánchez ◽  
Rafael Magaña-López ◽  
Julio C. Morales-Mejía ◽  
...  
Keyword(s):  
Electron Microscopy ◽  
Photocatalytic Activity ◽  
Surface Characteristics ◽  
Amorphous Solids ◽  
X Ray Diffraction ◽  
X Ray ◽  
Catalytic Activities ◽  
Anodic Spark Oxidation ◽  
Porous Surfaces ◽  
Scanning Electron

AbstractSeveral photocatalysts, based on titanium dioxide, were synthesized by spark anodization techniques and anodic spark oxidation. Photocatalytic activity was determined by methylene blue oxidation and the catalytic activities of the catalysts were evaluated after 70 hours of reaction. Scanning Electron Microscopy and X Ray Diffraction analysis were used to characterize the catalysts. The photocatalyst prepared with a solution of sulfuric acid and 100 V presented the best performance in terms of oxidation of the dye (62%). The electric potential during the synthesis (10 V, low potential; 100 V, high potential) affected the surface characteristics: under low potential, catalyst presented smooth and homogeneous surfaces with spots (high TiO2 concentration) of amorphous solids; under low potential, catalyst presented porous surfaces with crystalline solids homogeneously distributed.

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