scholarly journals FEATURES OF SYNTHESIS OF INORGANIC LUMINESCENT MATERIAL FROM PHOSPHOGYPSUM

2020 ◽  
Vol 63 (10) ◽  
pp. 46-52
Author(s):  
Nina P. Shabelskaya ◽  
Elena V. Vasilieva ◽  
Elena A. Yakovenko ◽  
Yulia S. Podkovyrina ◽  
Alina A. Skorynina
Keyword(s):  
Phase Analysis ◽  
Calcium Sulfate ◽  
Bound Water ◽  
Reduction Process ◽  
Fluorescence Analysis ◽  
Calcium Sulfide ◽  
Luminescent Material ◽  
Isothermal Exposure ◽  
X Ray ◽  
Initial Stage

The paper discusses technological methods for obtaining a luminescent material from phosphogypsum. The obtained materials were characterized using X-ray phase analysis, X-ray fluorescence analysis, and electron microscopy. The elemental composition of the samples was determined using a laboratory micro-fluorimeter. In the course of the study, the technological conditions for converting the main part of phosphogypsum into a luminescent material based on calcium sulfide were established. It is shown that the process of obtaining luminescent CaS consists of dehydration stages: the initial stage, carried out at a temperature of 373 K to remove physically bound water, and the final stage, at a temperature of 1073 K – to remove crystallization water, as well as the stage of phosphogypsum reduced at a temperature of 1173 K for 0.5 h. An environmentally friendly material-sucrose-is considered as a reducing agent. It is shown that in the case of changing the technological modes of reduction the luminescent material cannot be obtained. Conducting the reduction process at a temperature of 773 K is accompanied by obtaining a sample contaminated with products of incomplete decomposition of the organic component of the charge. In this case, the sample does not contain calcium sulfide. Under prolonged isothermal exposure at a temperature of 1173 K, repeated oxidation of samples with loss of luminescence ability was observed. Optimal technological modes for obtaining materials with phosphor properties are formulated. According to the results of X-ray phase analysis, samples that do not show luminescence capacity contain calcium sulfate as the main phase. Samples-phosphors consist of a mixture of calcium sulfate and sulfide. Results obtained open up wide opportunities for involving in the re-processing of production waste to obtain cheap products in demand.

scholarly journals Characterization of Ni-Cd Nanostructured System Obtained by Chemical Reduction of Salts

2016 ◽  
Vol 17 (4) ◽  
pp. 275 ◽  
Author(s):  
V.M. Pugachev ◽  
Yu.A. Zaharov ◽  
A.S. Valnyukova ◽  
V.G. Dodonov
Keyword(s):  
Chemical Reduction ◽  
Structural Parameters ◽  
Reduction Process ◽  
Metal Powders ◽  
X Ray Diffraction ◽  
X Ray ◽  
Initial Stage ◽  
Fcc Lattice ◽  
High Alkalinity

<p>The process of obtaining of highly dispersed metal powders of Ni-Cd system by reduction of their salts by hydrazine in aqueous medium at high alkalinity was investigated. The possibility of production metal powders containing up to 50 mol% of cadmium is established and conditions for their synthesis are optimized. Phase composition, structural parameters, dispersity of solid products during the reduction process were studied by X-ray diffraction (XRD) and SAXS. The formation of metal solid solutions with FCC lattice contradicts to the known phase diagram for Ni-Cd and may be explained by increasing the energy of the particles in the nanostate. The formation of intermetallide NiCd<sub>5</sub> in the studied compositions area is caused by sequential character of reduction process; as a result the metal product on the initial stage of reduction is significantly enriched with cadmium.</p>

scholarly journals Estimation of the Range of Variation in the Mineral Composition of Silicate Lake Bottom Sediments Using Data from XRD and XRF

2020 ◽  
pp. 260-272
Author(s):  
Roman V. Smelyi ◽  
Alexander L. Finkelshtein ◽  
Igor S. Yakimov ◽  
Alena A. Amosova ◽  
Victor M. Chubarov
Keyword(s):  
Phase Analysis ◽  
Mineral Composition ◽  
Bottom Sediments ◽  
Fluorescence Analysis ◽  
X Ray ◽  
Group Content ◽  
Lake Bottom ◽  
Mineral Components ◽  
Using Data ◽  
Lake Bottom Sediments

A method is proposed for estimating the range of mineral group content in the cores of silicate bottom sediments of lakes based on the search for the minimum and maximum content of stoichiometric minals that make up the group of minerals, provided that the balance of the mineral composition and the content of elements in the sample is observed. The mineral components were determined using the method of qualitative X-ray phase analysis, the contents of the main rock-forming elements were determined by X-ray fluorescence analysis. Comparison with the results of quantitative X-ray phase analysis showed that the contents of mineral groups either lie in the range calculated in the extreme search procedure based on data on the element composition, or overlap with the calculated range within the measurement error. The systematic discrepancy between the results of calculating the range of content of the silicon dioxide phase and the results of quantitative X-ray phase determination of quartz observed for the samples under consideration is due to the presence of an X-ray amorphous phase of biogenic silica. The proposed method for estimating the range of mineral group content is easy to implement, uses the publicly available MS Excel software, and can be useful for estimating variations in mineral composition by core depth, in conditions of frequent shortages of individual sample material distributed between different methods of analysis

Quantitative phase analysis of natural products using whole-powder-pattern decomposition

2000 ◽  
Vol 15 (2) ◽  
pp. 86-90 ◽  
Author(s):  
Shigeo Hayashi ◽  
Hideo Toraya
Keyword(s):  
Natural Products ◽  
Phase Analysis ◽  
Raw Materials ◽  
Fluorescence Analysis ◽  
Weight Percent ◽  
Powder Pattern ◽  
Quantitative Phase Analysis ◽  
X Ray ◽  
Quantitative Phase ◽  
Pattern Decomposition

The capability of whole-powder-pattern decomposition in the quantitative phase analysis (QPA) of natural products was investigated using three- to six-component mixtures and pottery bodies. Here, the term pottery body means plastic clay suitable for making pottery and it is compounded of ceramic raw materials. Average errors of the weight fractions for each phase were within 1 weight percent in each mixture of natural products. The amounts of reduced oxides in pottery bodies derived from the X-ray diffraction technique were in good agreement with results obtained by X-ray fluorescence analysis. The present procedure does not require knowledge of crystal structures; it appears adequate for the QPA of natural products.

scholarly journals Joint aluminothermic reduction of oxides Zr, Ta and Nb

2019 ◽  
Vol 60 (11) ◽  
pp. 11-15
Author(s):  
Andrey S. Russkih ◽  
◽  
Sergey N. Agafonov ◽  
Artem A. Ponomarenko ◽  
◽  
...  
Keyword(s):  
Phase Analysis ◽  
Reduction Process ◽  
Zirconium Alloys ◽  
Electrical Energy ◽  
Rare Metal ◽  
Scientific Basis ◽  
Gas Content ◽  
Target Component ◽  
X Ray ◽  
Degree Of Extraction

Alloys based on the Al-Zr system with insignificant Ta and Nb additives are in demand in the synthesis of complex alloys used to produce titanium alloys for aircraft and rocket technology. A common method for producing aluminum-zirconium alloys and ligatures is the out-of-furnace metallothermal reduction of zirconium from oxides and direct fusion of components. The practice of such methods has a number of significant disadvantages: poor separation of the metal and oxide phases, a low degree of extraction of the target component, the use of thermal additives, and the high cost of the resulting product. The solution to the problem may be a technology option where the temperature regime of the metallothermal reduction process is ensured both due to the heat of exothermic reactions and due to the additional supply of relatively inexpensive electrical energy. In this work, we investigated the possibility of obtaining alloys using metallothermal reduction from oxides based on ZrAl with Ta and Nb additives. An experimental technique for producing an alloy is presented. The data of X-ray phase analysis (XRD) and chemical analysis of the alloy. as well as an analysis of the content of oxygen and nitrogen in the alloy. X-ray phase analysis showed the formation of the ZrAl2 compound in all the studied alloys, as well as solid solutions (Zr4Nb)Al3, (Zr0.8Ta0.2)Al3, (Zr4Nb0.5Ta0.5)Al3 corresponding to the added element, ZrO2 is present in the 3 alloys, which tells us about not up to the reduced oxide Zr. These data are confirmed by analysis of the gas content in the alloy, where there is an increased oxygen content. The performed study can serve as a scientific basis for the development of promising metallothermal technologies for the production of rare metal alloys.

scholarly journals Phase Composition of Silicon in the Krasnoslobodsky Deposit of the Tambov Region

2021 ◽  
Vol 27 (1) ◽  
pp. 124-131
Author(s):  
D. M. Mordasov ◽  
◽  
M. D. Mordasov ◽  
Keyword(s):  
Phase Composition ◽  
Silicon Dioxide ◽  
Elemental Composition ◽  
Diffraction Pattern ◽  
Phase Analysis ◽  
Fluorescence Analysis ◽  
Modern Equipment ◽  
X Ray ◽  
Chemical And Phase Compositions

The study of the chemical and phase compositions of tripoli from Krasnoslobodskoye deposit in the Tambov region was carried out using modern equipment. Using the X-ray fluorescence analysis, the main elemental composition of the rock under study was established, determined mainly by the compounds of Si, Al, Fe, K, Mg, Ca, Ti, P, S, Na. It is shown that the proportion of silicon dioxide in the sample under study exceeds its content in tripoli from many Russian deposits and neighboring countries. The X-ray phase analysis with subsequent interpretation of the diffraction pattern showed that tripoli contains minerals of amorphous opal, microcrystalline - and -cristobalites as structural forms of silica, as well as small amounts of quartz, illite and montmorillonite impurities.

scholarly journals INVESTIGATION AND OPTIMIZATION OF COMPLEXATION OF MANGANESE (II) IONS WITH DIHY-DROQUERCETIN IN AQUEOUS SOLUTIONS

2020 ◽  
pp. 47-56
Author(s):  
Yelena Vladimirovna Stolpovskaya ◽  
Natalya Nikolaevna Trofimova ◽  
Vasily Anatolyevich Babkin ◽  
Spartak Spiridonovich Khutsishvili ◽  
Roman Georgievich Zhitov ◽  
...  
Keyword(s):  
Aqueous Solutions ◽  
Maximum Yield ◽  
Bound Water ◽  
Fluorescence Analysis ◽  
Molar Ratio ◽  
Complexation Reaction ◽  
Stoichiometric Ratio ◽  
Scanning Calorimetry ◽  
X Ray ◽  
Molar Ratios

The purpose of this work was to study and optimize the complexation reaction of Mn2+ ions with flavonoid dihydroquercetin (DHQ) in aqueous solutions. It was found that the interaction of DHQ (0.015–0.030 M) with manganese (II) salts at molar ratios of DHQ : Mn2+ from 1 : 1 to 1 : 3 at pH 6.9–7.9 leads to the formation of a complex compound (CC) with a stoichiometric ratio of metal : flavonoid ligand (Met : L) 1 : 1. The conditions for the complexation of Mn2+ ions with dihydroquercetin at laboratory conditions optimized for the yield of the product, are proposed. The maximum yield of the complex (95%) was achieved at the interaction of DHQ with Mn(CH3COO)2∙4H2O under conditions: pH 7.7, 70 °C, the reaction time was 15 min, the molar ratio of the initial reagents DHQ: Mn2+ was 1 : 1.5, the initial concentrations were 0.020 M DHQ and 0.030 M Mn2+. The most probable composition of the complex with the determination of the amount of bound water [MnL(OH)(H2O)2] and the structure of the complex were established using the data of thermogravimetry (TG), differential scanning calorimetry (DSC), elemental analysis and X-ray fluorescence analysis (XRF), confirmed by the data of total reflection X-ray fluorescence analysis (TXRF), and EPR spectroscopy data.

An x-ray microprobe based upon a close-coupled focal-spot / glass capillary arrangement

1992 ◽  
Vol 50 (2) ◽  
pp. 1758-1759
Author(s):  
D. A. Carpenter ◽  
M. A. Taylor
Keyword(s):  
Imaging Techniques ◽  
Fluorescence Analysis ◽  
High Sensitivity ◽  
Specimen Preparation ◽  
X Rays ◽  
Glass Capillary ◽  
Close Coupling ◽  
X Ray ◽  
Point To Point ◽  
Beam Damage

The development of intense sources of x rays has led to renewed interest in the use of microbeams of x rays in x-ray fluorescence analysis. Sparks pointed out that the use of x rays as a probe offered the advantages of high sensitivity, low detection limits, low beam damage, and large penetration depths with minimal specimen preparation or perturbation. In addition, the option of air operation provided special advantages for examination of hydrated systems or for nondestructive microanalysis of large specimens.The disadvantages of synchrotron sources prompted the development of laboratory-based instrumentation with various schemes to maximize the beam flux while maintaining small point-to-point resolution. Nichols and Ryon developed a microprobe using a rotating anode source and a modified microdiffractometer. Cross and Wherry showed that by close-coupling the x-ray source, specimen, and detector, good intensities could be obtained for beam sizes between 30 and 100μm. More importantly, both groups combined specimen scanning with modern imaging techniques for rapid element mapping.

XRMF applications of a monolithic, polycapillary, focusing x-ray optic

1996 ◽  
Vol 54 ◽  
pp. 240-241
Author(s):  
D. A. Carpenter ◽  
Ning Gao ◽  
G. J. Havrilla
Keyword(s):  
Trace Elements ◽  
Point Source ◽  
Focal Spot ◽  
Fluorescence Analysis ◽  
X Rays ◽  
Focal Distance ◽  
Spot Diameter ◽  
X Ray ◽  
Focal Spot Diameter

A monolithic, polycapillary, x-ray optic was adapted to a laboratory-based x-ray microprobe to evaluate the potential of the optic for x-ray micro fluorescence analysis. The polycapillary was capable of collecting x-rays over a 6 degree angle from a point source and focusing them to a spot approximately 40 µm diameter. The high intensities expected from this capillary should be useful for determining and mapping minor to trace elements in materials. Fig. 1 shows a sketch of the capillary with important dimensions.The microprobe had previously been used with straight and with tapered monocapillaries. Alignment of the monocapillaries with the focal spot was accomplished by electromagnetically scanning the focal spot over the beveled anode. With the polycapillary it was also necessary to manually adjust the distance between the focal spot and the polycapillary.The focal distance and focal spot diameter of the polycapillary were determined from a series of edge scans.

Identification of acid-insoluble filter-plugging compounds and optimal acid-washing procedures for tubular backpulse pressure filters

TAPPI Journal ◽  
2011 ◽  
Vol 10 (1) ◽  
pp. 17-23
Author(s):  
KEVIN TAYLOR ◽  
RICH ADDERLY ◽  
GAVIN BAXTER
Keyword(s):  
Calcium Sulfate ◽  
Membrane Filter ◽  
Sulfamic Acid ◽  
Xrd Analysis ◽  
Metal Sulfides ◽  
X Ray Diffraction ◽  
X Ray ◽  
Gypsum Formation ◽  
Acid Washing ◽  
Hydrolysis Of

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.

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