scholarly journals Application of XRF Scanning to Different Geological Archives

2021 ◽  
Vol 8 (9) ◽  
Author(s):  
Fei Guo ◽  
Steven Clemens ◽  
Xingxing Liu ◽  
Yili Long ◽  
Dong Li ◽  
...  
Keyword(s):  
Xrf Scanning

Chemical imaging of stained-glass windows by means of macro X-ray fluorescence (MA-XRF) scanning

2016 ◽  
Vol 124 ◽  
pp. 615-622 ◽  
Author(s):  
Geert Van der Snickt ◽  
Stijn Legrand ◽  
Joost Caen ◽  
Frederik Vanmeert ◽  
Matthias Alfeld ◽  
...  
Keyword(s):  
Chemical Imaging ◽  
Stained Glass ◽  
X Ray ◽  
Xrf Scanning

Analysis of CoCrMo Surface Oxide Removal by Alumina Blasting before Porcelain Firing in Dental Restorations

2012 ◽  
Vol 730-732 ◽  
pp. 9-14 ◽  
Author(s):  
Bruno Henriques ◽  
Filipe Silva ◽  
Delfim Soares
Keyword(s):  
Heat Treatment ◽  
Surface Roughness ◽  
Chemical Composition ◽  
High Alumina ◽  
X Ray ◽  
Dental Restorations ◽  
Ceramic Bond ◽  
Xrf Scanning ◽  
Oxide Removal

The purpose of this work was to perform a chemical and mechanical characterization of a preoxidized CoCrMo alumina blasted surface. This is a commonly performed surface treatment used in metal-porcelain systems for dental restorations to remove oxides formed during preoxidation heat treatment from the metal’s surface. CoCrMo dental alloy’s specimens produced by lost wax process were examined in terms of chemical composition using X-Ray fluorescence spectroscopy (XRF), Scanning Electron Microscopy (SEM) and Energy Dispersive X-Ray Spectroscopy (EDS); in terms of mechanical characteristics through the means of a microhardness test and in terms of surface roughness using a profilometer. It was investigated the chemical composition of various surface conditions: non-preoxidized, preoxidized, ground oxidized surface and sandblasted oxidized surface. After alumina blasting, the oxides level on metal’s surface remained high. Alumina blasting treatment (Ø110 µm) produced an 84% increase of CoCrMo surface hardening and an increase in surface roughness (Ra=0.58 µm). It was found alumina contaminants on the metal’s surface. Therefore, it was concluded that alumina blasting do not entirely removes the oxide layer formed during preoxidation heat treatment. It produced a chemical and mechanical surface modification that can influence the metal-ceramic bond strength.

scholarly journals CHARACTERISTIC OF XONOTLITE SYNTHESIZED BY HYDROTHERMAL REACTION USING RICE HUSK ASH AND ITS APPLICATION TO ABSORB CHROME (III) SOLUTION

2021 ◽  
Vol 55 (6) ◽  
Author(s):  
Trung Kien Pham ◽  
Tran Ngo Quan
Keyword(s):  
Rice Husk ◽  
Rice Husk Ash ◽  
Hydrothermal Reaction ◽  
Mekong Delta ◽  
Molar Ratio ◽  
X Ray ◽  
Vis Spectroscopy ◽  
Xrf Scanning ◽  
Before And After ◽  
Chrome Iii

In this paper, we report on synthesizing xonotlite, calcium silicate hydrate (CSH), via a hydrothermal reaction using rice husk from the Mekong Delta, Vietnam. The rice husks were burnt at 1000 °C for 3 h. Grey rice husk ash was collected, then mixed with Ca(OH)2 at a Ca/Si molar ratio of 1 : 1. This was followed by a hydrothermal reaction at 180 °C for 24 h and 48 h to obtain the xonotlite mineral. Before and after adsorption, 3-mm xonotlite pellets were thoroughly characterized using X-ray diffractometry (XRD), X-ray fluorescence (XRF), scanning electron microscopy (SEM) and ultraviolet-visible (UV-VIS) spectroscopy. This material has potential application in chromium(III) removal during a chrome-plating process. The adsorption efficiency of the 3-mm pellet samples reached more than 76 % after 12 h.

scholarly journals Data report: summary of XRF scanning on core sections, IODP Expedition 381

2019 ◽  
Author(s):  
L.C. McNeill ◽  
G. De Gelder ◽  
M.L. Machlus ◽  
N. Fabregas ◽  
C. Mahoney ◽  
...  
Keyword(s):  
Xrf Scanning

scholarly journals The potentional of plants to cleanup metals from an old landfill site

2017 ◽  
Author(s):  
Yahya Jani ◽  
Charlotte Marchand ◽  
William Hogland
Keyword(s):  
Contaminated Soils ◽  
Hazardous Materials ◽  
Average Concentration ◽  
Soil Samples ◽  
Landfill Site ◽  
Group Company ◽  
Timothy Grass ◽  
Xrf Scanning ◽  
High Concentrations ◽  
The Stability

Old landfill sites contain different hazardous materials like heavy metals which have the ability to affects the entire environment. These places are sometimes covered by plants to increase the stability of the soil and to reduce the effects of erosion. 15 soil samples (3 samples from each place) and 5-7 timothy-grass (Phleum pretense) plants from 5 different places were taken from an old landfill place in an active landfill site in Högbytorp /Sweden owned by Ragn-sells Group Company. XRF scanning was used to analyze the metal content of soil samples and of plants. High concentrations of metals were detected in the soil samples like Fe with an average of about 25000 ppm, Mn about 250 ppm and 2800 ppm of Ti. The plants results showed an average concentration of Fe in the shoots about 730 ppm, Mn about 60 ppm and Ti about 1760 ppm. On the other hand, the roots results showed an average concentration of about 10 000 ppm of Fe, about 160 ppm of Mn and 2200 ppm of Ti. These results gave the indication that the Timothy-grass has the ability to extract metals from contaminated soils and can help to cleanup these soils.

scholarly journals Hydrogen desorption kinetics of MgH2 synthesized from modified waste magnesium

2014 ◽  
Vol 32 (3) ◽  
pp. 385-390
Author(s):  
Aysel Kantürk Figen ◽  
Bilge Coşkuner ◽  
Sabriye Pişkin
Keyword(s):  
Hydrogen Desorption ◽  
Nitrogen Atmosphere ◽  
Desorption Kinetics ◽  
X Ray Diffraction ◽  
Heating Rates ◽  
Scanning Calorimetry ◽  
X Ray ◽  
Xrf Scanning ◽  
Isothermal Kinetic ◽  
Kinetics Of

AbstractIn the present study, hydrogen desorption properties of magnesium hydride (MgH2) synthesized from modified waste magnesium chips (WMC) were investigated. MgH2 was synthesized by hydrogenation of modified waste magnesium at 320 °C for 90 min under a pressure of 6 × 106 Pa. The modified waste magnesium was prepared by mixing waste magnesium with tetrahydrofuran (THF) and NaCl additions, applying mechanical milling. Next, it was investigated by X-ray diffraction (XRD), X-ray fluorescence (XRF), scanning electron microscopy (SEM) and Brunauer-Emmett-Teller (BET) techniques in order to characterize its structural properties. Hydrogen desorption properties were determined by differential scanning calorimetry (DSC) under nitrogen atmosphere at different heating rates (5, 10, and 15 °C/min). Doyle and Kissenger non-isothermal kinetic models were applied to calculate energy (Ea) values, which were found equal to 254.68 kJ/mol and 255.88 kJ/mol, respectively.

scholarly journals Preparation, Characterization, and Photocatalytic Properties of Modified Red Mud

2015 ◽  
Vol 2015 ◽  
pp. 1-6 ◽  
Author(s):  
Mingjie Ma ◽  
Guanyu Wang ◽  
Zhengpeng Yang ◽  
Shanxiu Huang ◽  
Weijie Guo ◽  
...  
Keyword(s):  
Electron Microscopy ◽  
Aqueous Solution ◽  
Scanning Electron Microscopy ◽  
Uv Irradiation ◽  
Red Mud ◽  
Structure Property ◽  
X Ray Diffraction ◽  
X Ray ◽  
Xrf Scanning ◽  
Scanning Electron

Solid waste red mud was modified by HCl leaching. The structure property and composition of modified red mud were investigated by X-ray diffraction (XRD), X-ray fluorescence spectroscopy (XRF), scanning electron microscopy (SEM), and Brunauer-Emmett-Teller (BET). Under UV irradiation, methyl orange (MO) aqueous solution was photodegraded by modified red mud. The obtained results showed that the specific surface area of modified red mud was 317.14 m2/g, which was about 40 times higher than that of the normal red mud. After UV irradiation for 50 min, the removal percentage of MO reached 94.2%. The study provided a novel way for the application of red mud to the photocatalytic degradation of organic wastes.

Testing the analytical performance of handheld XRF using marine sediments of IODP Expedition 355

2019 ◽  
Vol 157 (6) ◽  
pp. 956-960 ◽  
Author(s):  
A. Hahn ◽  
M. G. Bowen ◽  
P. D. Clift ◽  
D. K. Kulhanek ◽  
M. W. Lyle
Keyword(s):  
Standard Procedure ◽  
Quality Data ◽  
Geochemical Data ◽  
Stratigraphic Correlation ◽  
Common Denominator ◽  
Handheld Device ◽  
Xrf Analysis ◽  
Xrf Scanning ◽  
International Ocean Discovery Program ◽  
Handheld Xrf

AbstractObtaining geochemical profiles using X-ray fluorescent (XRF) techniques has become a standard procedure in many sediment core studies. The resulting datasets are not only important tools for palaeoclimatic and palaeoceanographic reconstructions, but also for stratigraphic correlation. The International Ocean Discovery Program (IODP) has therefore recently introduced shipboard application of a handheld XRF device, making geochemical data directly available to the science party. In all XRF scanning techniques, the physical properties of wet core halves cause substantial analytical deviations. In order to obtain estimates of element concentrations (e.g. for quantitative analyses of fluxes or mass-balance calculations), a calibration of the scanning data is required. We test whether results from the handheld XRF analysis on discrete samples are suitable for calibrating scanning data. Log-ratios with Ca as a common denominator were calculated. The comparison between the handheld device and conventional measurements show that the latter provide high-quality data describing Al, Si, K, Ca, Ti, Mn, Fe, Zn, Rb and Sr content (R2 compared with conventional measurements: ln(Al/Ca) = 0.99, ln(Si/Ca) = 0.98, ln(K/Ca) = 0.99, ln(Ti/Ca) = 0.99, ln(Mn/Ca) = 0.99, ln(Fe/Ca) = 0.99, ln(Zn/Ca) = 0.99 and ln(Sr/Ca) = 0.99). Our results imply that discrete measurements using the shipboard handheld analyser are suitable for the calibration of XRF scanning data. Our test was performed on downcore sediments from IODP Expedition 355 that display a wide variety of lithologies of both terrestrial and marine origin. The implication is that our findings are valid on a general scale and that shipboard handheld XRF analysis on discrete samples should be used for calibrating XRF scanning data.

scholarly journals Bromine counts from XRF scanning as an estimate of the marine organic carbon content of sediment cores

2008 ◽  
Vol 9 (5) ◽  
pp. n/a-n/a ◽  
Author(s):  
Martin Ziegler ◽  
Tom Jilbert ◽  
Gert J. de Lange ◽  
Lucas J. Lourens ◽  
Gert-Jan Reichart
Keyword(s):  
Organic Carbon ◽  
Carbon Content ◽  
Sediment Cores ◽  
Organic Carbon Content ◽  
Xrf Scanning ◽  
Marine Organic Carbon

scholarly journals Calcium Oxide Derived from Waste Shells of Mussel, Cockle, and Scallop as the Heterogeneous Catalyst for Biodiesel Production

2013 ◽  
Vol 2013 ◽  
pp. 1-7 ◽  
Author(s):  
Achanai Buasri ◽  
Nattawut Chaiyut ◽  
Vorrada Loryuenyong ◽  
Phatsakon Worawanitchaphong ◽  
Sarinthip Trongyong
Keyword(s):  
Calcium Oxide ◽  
Heterogeneous Catalysts ◽  
Biodiesel Production ◽  
Molar Ratio ◽  
Catalyst Loading ◽  
X Ray ◽  
Bet Method ◽  
Xrf Scanning ◽  
Waste Shell ◽  
Calcination Method

The waste shell was utilized as a bioresource of calcium oxide (CaO) in catalyzing a transesterification to produce biodiesel (methyl ester). The economic and environmen-friendly catalysts were prepared by a calcination method at 700–1,000°C for 4 h. The heterogeneous catalysts were characterized by X-ray diffraction (XRD), X-ray fluorescence (XRF), scanning electron microscopy (SEM), and the Brunauer-Emmett-Teller (BET) method. The effects of reaction variables such as reaction time, reaction temperature, methanol/oil molar ratio, and catalyst loading on the yield of biodiesel were investigated. Reusability of waste shell catalyst was also examined. The results indicated that the CaO catalysts derived from waste shell showed good reusability and had high potential to be used as biodiesel production catalysts in transesterification of palm oil with methanol.

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