A Rapid, Low Cost, Manual Fusion Sample Preparation Technique for Quantitative X-Ray Fluorescence Analysis

1983 ◽  
Vol 27 ◽  
pp. 491-496
Author(s):  
Gerald D. Bowling ◽  
Iris B. Ailin-Pyzik ◽  
David R. Jones

This study compares the quality of the fused samples obtained by three separate methods. The first set of samples was prepared by the method used at USGS in Denver and reported by Taggart and Whalberg (1). The second set was fused by our manual method and cast in graphite molds. The third set was fused in the Herzog HAG-12 automated fusion device.The manual fusion technique requires the use of a muffle furnace capable of 1100°C (2100°F) and graphite molds. No release agents such as KBr and LiBr are required since the disks release easily from the graphite. The 25mm diameter center of the “fire-polished” upper surface of the disk is used for analysis without further surface preparation. This method has been shown to be suitable for preparation of a wide variety of glasses and raw materials including burned dolomite, silicates* high zircon materials such as BCS-388, calcined alumina and alumina refractories.

2018 ◽  
Vol 170 ◽  
pp. 03018 ◽  
Author(s):  
Andrey Medvedev ◽  
Ekaterina Bobrova ◽  
Alexey Poserenin ◽  
Ervand Zarmanyan

The article analyzes the factors affecting the longevity of insu-lating systems and the operational resistance of products based on mineral fibers. It is emphasized that the ratio of acid oxides contained in the charge to the main oxides is the main factor influencing the operational resistance of mineral fibers, as well as the energy intensity of their production. A hy-pothesis has been put forward and confirmed that the operational resistance of a fiber depends on the content of heavy metals (their oxides) in the ini-tial charge. Determination of the elemental composition of stone wool samples was carried out by X-ray fluorescence analysis. Conducted sam-ples with a different acidity module of the study, show, that the fibers are safe by radiation indices, and their operational resistance can be affected by heavy metal oxides. It is substantiated that the durability of building systems in which mineral wool products are used as thermal insulation is determined by the properties of mineral wool products, the literacy of de-sign solutions and the quality of installation. The properties of mineral wool products, including their operational resistance, depend on the prop-erties of mineral fibers and the observance of technological regimes both on the fact of the most complete curing of the binder and on the features of formation of the volume-oriented structure of the mineral wool carpet.


1998 ◽  
Vol 537 ◽  
Author(s):  
M. Suscavage ◽  
M. Harris ◽  
D. Bliss ◽  
P. Yip ◽  
S.-Q. Wang ◽  
...  

AbstractZinc Oxide crystals have historically been grown in hydrothermal autoclaves with a basic mineralizer; however, doubts have been raised about the quality of such crystals because they have often exhibited large x-ray rocking curve widths and low photoluminescence (PL) yield with large linewidths. Several ZnO crystals were grown hydrothermally and sliced parallel to the c-plane. This resulted in opposite surfaces (the C+ and C-) exhibiting pronounced chemical and mechanical differences. Different surface treatments were investigated and compared by PL both at room temperature and liquid helium temperatures, and by double axis X-ray rocking curve measurements. The high quality of hydrothermally-grown ZnO is substantiated by the narrow rocking curve widths and sharp PL peaks obtained. A critical factor in obtaining these results was found to be surface preparation.


2014 ◽  
Vol 936 ◽  
pp. 986-991
Author(s):  
Chuan Hui Gao ◽  
Li Ding ◽  
Yu Min Wu ◽  
Chuan Xing Wang ◽  
Jun Xu

A low-cost raw material, bittern obtained from the production process of sea salt, was used to prepare magnesium oxysulfate hydrate (MgSO4·5Mg (OH)2·2H2O, abbreviated as 152MOS) whiskers via hydrothermal synthesis with ammonia and magnesium sulfate as the other starting raw materials. The bittern was firstly filtered and then used directly without de-coloring. X-ray powder diffraction (XRD), transmission electron microscope (TEM), selected area electron diffraction (SAED), energy dispersive X-ray spectroscopy (EDX) and scanning electron microscope (SEM) were employed to investigate the composition and morphology of the products. It was found that the 152MOS whiskers synthesized from bittern at 190°C for 3 hours exhibited fanlike morphology. The formation of the fanlike whiskers was inhibited and most of the whiskers presented as single fibers when ethanol was used as crystal control agent in the hydrothermal process. From the two-dimensional steps observed at tips of the whiskers, a possible growth mechanism was speculated that it was the extension of dislocations that made the growth of the whiskers.


1968 ◽  
Vol 12 ◽  
pp. 546-562
Author(s):  
R. Tertian

AbstractThe double dilution method has many important advantages. For any element to be determined, let us say A, It enables us to control or calculate the matrix factor (sum of the absorption end enhancement effects) for the sample being Investigated towards A radiation, and it furnishes corrected Intensities which are strictly proportional to A concentration. Thus the results are exact, whatever the general composition of the sample, their accuracy depending only on the quality of measurement and preparation. Another major practical advantage is that the method does not require systematic calibration but only a few permanent standards consisting of a pure compound or of an accurately known sample.The procedure has been tested successfully for accurate determination of rare earth elements using, for solid materials such as ores and oxide mixtures, the borax fusion technique. It also can be readily applied to liquids. All the rare earth elements can be titrated by that method, as well as yttrium, thorium and, if necessary, all the elements relevant to X-ray fluorescence analysis. The concentration range considered for solids is of one comprised between 0.5 and 100 % and, with a lesser accuracy, between 0.1 and 0-5 % Examples are given relative to the analysis of various ores. Finally it rcust be pointed out that the method is universal and applies to the analysis of every solid, especially ores, provided that they can be converted to solid or liquid solutions. It appears that most industrial analyses can be worked on In this way.


2016 ◽  
Vol 714 ◽  
pp. 116-121 ◽  
Author(s):  
Ester Helanova ◽  
Rostislav Drochytka ◽  
Vit Cerný

The quality of the aerated concrete strongly depends on the chemical composition of the raw materials, as well as the process of the hydrothermal reaction during autoclaving. Due to the variable chemical composition of fly ashes, it is necessary to identify the effect of each ion on the formation of the microstructure of aerated concrete. This paper examines the process of formation of tobermorite with the addition of sulphates in various percentage representation. The microstructure of aerated concrete is assessed using SEM images and the mineralogical by means of X-ray analysis.


2009 ◽  
Vol 42 (4) ◽  
pp. 636-641 ◽  
Author(s):  
Stefano Oberti ◽  
Dirk Möller ◽  
Sascha Gutmann ◽  
Adrian Neild ◽  
Jürg Dual

In order to perform X-ray crystallographic analysis, protein crystals are removed from their growing solution by means of a nylon loop, which is then mounted on a goniometer. As this process is repeated for a large number of crystals, there is a need for automation, especially with regard to the placement on the nylon loop. A novel technique involving the use of acoustic radiation forces and a micro-machined fluidic device is introduced here. After insertion into the micro-machined channel, the crystals are positioned in a row along its centre-line by excitation of a high-frequency standing pressure field, and then moved towards an orifice by applying a flow along the channel, which also ensures spatial separation. Once located in a defined orifice, the single crystals can be removed using a nylon loop. X-ray crystallographic analysis showed that application of ultrasound does not influence the diffraction properties of the crystals.


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