scholarly journals Improving the technology of gold ore X-ray radiometric separation

2021 ◽  
Vol 1 (3) ◽  
pp. 88-96
Author(s):  
Vadim I. Kulikov
Keyword(s):  
Chemical Elements ◽  
Decision Criterion ◽  
Development Research ◽  
Characteristic Radiation ◽  
X Ray ◽  
Gold Ore ◽  
Sulfide Ore ◽  
Specific Deposit ◽  
Intensive Search ◽  
Secondary Characteristic

Introduction. Gold ore pre-concentration is an urgent issue that can efficiently be solved by the technology of X-ray radiometric separation (XRS). Quarts and quarts-sulfide gold ore XRS is based on the methods of indirect sorting by gold accompanying chemical elements or genetic associate minerals laying the foundation for the creation of separation characteristics for these ores. Additional separation characteristics are required for efficient gold-quartz and gold-quartz-sulfide ore sorting; Irgiredmet Research Institute works on these characteristics search and development. Research methodology. Optimal ore separation characteristics for each specific deposit are chosen after studying and analyzing the spectral information acquired at XRF separators when detecting secondary characteristic radiation from each specific deposit ore samples. The recent modernization of XRF separators significantly enhanced the technological capabilities of XRS concerning intensive search and study of new separation characteristics for gold ore. It has been established that most ores can be efficiently sorted by three characteristics. Research results. A new method of gold ore XRS has been developed which consists of simultaneously applying three, two, or one decision criterion of a lump separation depending on the type, geologicalmineralogical properties, and material composition of the processed ore

Contribution of x-ray total reflection to the background intensity in EPMA

1990 ◽  
Vol 48 (2) ◽  
pp. 202-203
Author(s):  
Werner P. Rehbach ◽  
Peter Karduck
Keyword(s):  
Atomic Number ◽  
Target Material ◽  
Total Reflection ◽  
Background Intensity ◽  
X Rays ◽  
Characteristic Radiation ◽  
X Ray

In the EPMA of soft x rays anomalies in the background are found for several elements. In the literature extremely high backgrounds in the region of the OKα line are reported for C, Al, Si, Mo, and Zr. We found the same effect also for Boron (Fig. 1). For small glancing angles θ, the background measured using a LdSte crystal is significantly higher for B compared with BN and C, although the latter are of higher atomic number. It would be expected, that , characteristic radiation missing, the background IB (bremsstrahlung) is proportional Zn by variation of the atomic number of the target material. According to Kramers n has the value of unity, whereas Rao-Sahib and Wittry proposed values between 1.12 and 1.38 , depending on Z, E and Eo. In all cases IB should increase with increasing atomic number Z. The measured values are in discrepancy with the expected ones.

X-ray mapping without STEM

1994 ◽  
Vol 52 ◽  
pp. 508-509
Author(s):  
Judith M. Brock ◽  
Max T. Otten
Keyword(s):  
Life Science ◽  
Materials Science ◽  
Chemical Elements ◽  
Full Description ◽  
Scanning System ◽  
Elemental Distribution ◽  
X Ray ◽  
Transmission Electron ◽  
Distribution Of Elements ◽  
Made In

A knowledge of the distribution of chemical elements in a specimen is often highly useful. In materials science specimens features such as grain boundaries and precipitates generally force a certain order on mental distribution, so that a single profile away from the boundary or precipitate gives a full description of all relevant data. No such simplicity can be assumed in life science specimens, where elements can occur various combinations and in different concentrations in tissue. In the latter case a two-dimensional elemental-distribution image is required to describe the material adequately. X-ray mapping provides such of the distribution of elements.The big disadvantage of x-ray mapping hitherto has been one requirement: the transmission electron microscope must have the scanning function. In cases where the STEM functionality – to record scanning images using a variety of STEM detectors – is not used, but only x-ray mapping is intended, a significant investment must still be made in the scanning system: electronics that drive the beam, detectors for generating the scanning images, and monitors for displaying and recording the images.

Processing of granite quarry solid waste into industrial high silica materials using leaching process with HCl concentration variation

2020 ◽  
Vol 11 (2) ◽  
pp. 43-50
Author(s):  
Yusup Hendronursito ◽  
Muhammad Amin ◽  
Slamet Sumardi ◽  
Roniyus Marjunus ◽  
Frista Clarasati ◽  
...  
Keyword(s):  
Particle Size ◽  
Rotational Speed ◽  
Inductively Coupled Plasma ◽  
Chemical Elements ◽  
Silica Content ◽  
X Ray ◽  
Concentration Variation ◽  
Leaching Process ◽  
Hcl Concentration ◽  
Granite Powder

This study was aimed to increase granite's silica content using the leaching process with HCl concentration variation. The granite used in this study came from Lematang, South Lampung. This study aims to determine the effect of variations in HCl concentration, particle size, and rotational speed on the crystalline phase and chemical elements formed in the silica product produced from granite. The HCl concentration variations were 6.0 M, 7.2 M, 8.4 M, and 9.6 M, the variation in particle size used was 270 and 400 mesh. Variations in rotational speed during leaching were 500 and 750 rpm. Granite powder was calcined at 1000 ºC for 2 hours. Characterization was performed using X-Ray Fluorescence (XRF), X-Ray Diffraction (XRD), and Inductively Coupled Plasma-Optical Emission Spectroscopy (ICP- OES). The results showed that the silica content increased with increasing HCl concentration, the finer the particle size, and the higher the rotational speed. XRF analysis showed that the silica with the highest purity was leached with 9.6 HCl with a particle size of 400 mesh and a rotational speed of of 750 rpm, which was 73.49%. Based on the results above, by leaching using HCl, the Si content can increase from before. The XRD diffractogram showed that the granite powder formed the Quartz phase.

On the X-Ray Absorption Frequencies Characteristic of the Chemical Elements

1919 ◽  
Vol 14 (6) ◽  
pp. 522-524 ◽  
Author(s):  
William Duane ◽  
Takeo Shimizu
Keyword(s):  
Chemical Elements ◽  
X Ray ◽  
X Ray Absorption ◽  
Absorption Frequencies

CHARACTERISTICS OF AEROSOLS IN BEIJING-TIANJIN AREA OF CHINA BY PIXE AND INAA AND IDENTIFICATION OF THEIR SOURCES BY CEB

1992 ◽  
Vol 02 (04) ◽  
pp. 593-601 ◽  
Author(s):  
Sha Yin ◽  
Liu Pingsheng ◽  
Hu Zhaohui ◽  
Zhong Ming ◽  
Yang Shaojin ◽  
...  
Keyword(s):  
Coal Combustion ◽  
Fine Particles ◽  
Motor Vehicle ◽  
Chemical Elements ◽  
Sea Salt ◽  
Soil Dust ◽  
Air Filter ◽  
X Ray ◽  
Sea Salt Aerosol ◽  
Limestone Dust

Proton Induced X-ray Emission (PIXE) and Instrumental Neutron Activation Analysis (INAA) techniques were used to measure the contents of 45 elements in 150 air-filter samples collected by cascade impactor with 8 stages at 10 sites in Beijing-Tianjin area of China during the periods of the winter of 1983 and the summer of 1984. It was noticed that the toxic elements such as As, Sb, Se, Pb, Hg, Cu and Ni were mainly enriched in fine particles with diameter less than 2 um. The major seven sources of coal burning, soil dust, oi1 burning, sea-salt aerosol, motor vehicle emission, limestone dust and industrial refuse attributing to the pollution in Tianjin area were identified by Chemical Elements Balance method (CEB). Among them the most important sources were the soil dust and the emission from coal-combustion followed by contributions from limestone and industrial refuse.

scholarly journals What the presence of regulated chemical elements in beached lacustrine plastics can tell us: the case of Swiss lakes

2021 ◽  
Vol 193 (11) ◽  
Author(s):  
Montserrat Filella ◽  
Juan-Carlos Rodríguez-Murillo ◽  
Andrew Turner
Keyword(s):  
Polyvinyl Chloride ◽  
Flame Retardants ◽  
Chemical Elements ◽  
Fluorescence Spectrometry ◽  
Lake Geneva ◽  
Plastic Pollution ◽  
X Ray ◽  
Management Schemes ◽  
Standing Stocks ◽  
Insight Into

AbstractPlastics (n = 3880) have been sampled from 39 beaches of ten Swiss lakes of varying sizes, hydrodynamics, and catchments, with a selection (n = 598) analysed for potentially hazardous (and regulated) chemical elements (As, Ba, Br, Cd, Cr, Hg, Pb, Sb, Se) by X-ray fluorescence spectrometry. Plastic objects and fragments with identifiable or unidentifiable origins were present on all beaches surveyed, and were often most abundant in proximity to major riverine inputs. Chemical elements were detected in between two (Hg) and 340 (Ba) samples with maximum concentrations exceeding 2% by weight for Ba, Cd, Cr, Pb, and Sb. Inter-element relationships and characteristics of the samples suggest that elements are largely present as various additives, including pigments (e.g., Cd2SSe, PbCrO4), stabilizers (in polyvinyl chloride), and flame retardants (Br). Observations are similar to, and complement, those previously reported in Switzerland’s largest lake (Lake Geneva). Comparison of concentrations of targeted chemical elements in beached plastic with currently used plastics illustrate the interest of these types of measurements in providing an insight into the persistence of plastics in standing stocks and in lakes. This information could help to introduce management schemes that consider whether plastic pollution is new or old and act accordingly.

scholarly journals Metallic Composition Analysis of Crude Petroleum from Some Oil Fields in Ghana

2021 ◽  
pp. 19-29
Author(s):  
Robert Wilson ◽  
Calvin Kwesi Gafrey ◽  
George Amoako ◽  
Benjamin Anderson
Keyword(s):  
Chemical Elements ◽  
Earth Metal ◽  
Oil Field ◽  
Oil Fields ◽  
Composition Analysis ◽  
Crude Petroleum ◽  
Reservoir Properties ◽  
Exciting Field ◽  
Nuclear Research Institute ◽  
X Ray

Qualitative and quantitative analyses of chemical elements in crude petroleum using energy-dispersive X-ray fluorescence spectroscopic technique has attracted the attention of scientific world because it is fast, cheap, non-destructive and assurance in quality compared to other methods. Metallic element characterisation of crude petroleum is important in the petrochemical industry because it determines rock reservoir properties, the technology needed for extraction and refinery process, hence an exciting field that calls for research. X-ray fluorescence method was used for metallic composition analysis of four rundown crude petroleum samples (SB-2, SB-4, TB-2 and TB-1) from three oil fields (Saltpond, TEN and Jubilee). It was conducted at the National Nuclear Research Institute of Ghana. Analysis of the four samples concluded that oil field maturity decreases orderly from Saltpond, Jubilee and TEN. Vanadium-nickel ratios for each crude petroleum sample was less than 0.5, indicating that both Saltpond and Tano sedimentary rocks are of marine organic origin. Higher concentration levels of rare earth metal elements (scandium and yttrium) in the Saltpond sedimentary basin compared to Tano sedimentary rock suggest seismic effect of McCarthy Hills on Saltpond Basin. The strong negative correlation between the vanadium-nickel ratio (predictor) and scandium concentration (dependent) among the three oil fields implies that scandium concentration can equally be used to characterise the oil fields just as the vanadium-nickel ratios.

scholarly journals Case Study On The Relationships Between Soil Contents Of Some Harmful Chemical Elements Determined By Different Equipment

2015 ◽  
Vol 1 ◽  
pp. 89
Author(s):  
Rimantė Zinkutė ◽  
Ričardas Taraškevičius
Keyword(s):  
Linear Relationship ◽  
Chemical Elements ◽  
Linear Equations ◽  
Atomic Emission ◽  
Energy Dispersive ◽  
X Ray ◽  
Edxrf Analysis

Comparison of total contents of Ba, Cr, Cu, Mn, Mo, Ni, Sn, Pb, V, Zn, Al, Ca, Fe, Mg determined in topsoil of central part of Vilnius by optical atomic emission spectrophotometry (OAES) with respective contents determined by energy-dispersive x-ray fluorescence (EDXRF), analysis of their correlation and linear relationship with and without outliers are the tasks of research. For most elements, except Ca, Sn, Ba, the contents determined by EDXRF are significantly lower and less variable. They can be predicted according to OAES-contents using linear equations. After elimination of outliers for all elements the correlation is significant at p<0.05.

scholarly journals FEATURES OF DENTINE CHEMICAL COMPOSITION OF INTACT TEETH AND TEETH WITH WEDGE-SHAPED DEFECTS

2021 ◽  
Vol 74 (8) ◽  
pp. 1869-1875
Author(s):  
Svitlana P. Yarova ◽  
Iryna I. Zabolotna ◽  
Olena S. Genzytska ◽  
Andrii A. Komlev
Keyword(s):  
Chemical Composition ◽  
Chemical Elements ◽  
Cervical Region ◽  
Cervical Lesions ◽  
X Ray ◽  
Sodium Magnesium ◽  
Calcium Phosphorus ◽  
Cervical Area ◽  
Focused Beam

The aim: Is to define dentine chemical composition of intact teeth and those with wedge-shaped defects followed by the analysis of revealed differences. Materials and methods: Longitudinal sections of 22 clinically removed teeth (12 – clinically intact ones, 10 – with wedge-shaped defects) from both jaws were studied in patients aged between 25-54 years. JSM-6490 LV focused beam electron microscope (scanning) with system of energy-dispersive X-ray microanalysis INCA Penta FETх3 was used. The chemical composition of 148 dentine areas in the incisal region (tubercle), equator, cervical area has been determined as a percentage of the weight amounts of carbon, oxygen, calcium, phosphorus, sodium, magnesium, sulfur, chlorine, zinc, potassium, aluminum. Results: Dentine chemical composition of teeth with wedge-shaped defects differed from those of intact teeth by significantly lower content: sodium, chlorine and calcium – in the incisal region (tubercle); sodium, magnesium − at the equator; sodium, chlorine and calcium – in the cervical region (p≤0.05). In the sample groups with cervical pathology there was more sulfur and oxygen in the incisal region (tubercle), phosphorus and zinc – at the equator, carbon and potassium – in the cervical region (p≤0.05). Conclusions: Differences in the chemical composition of intact teeth and teeth with wedge-shaped defects, the presence of correlation between the studied chemical elements confirm the role of macro- and microelements in the pathogenesis of non-carious cervical lesions.

scholarly journals Determination of chemical elements and cross-section hardness of sclerotic darkened human dentin

2017 ◽  
Vol 20 (3) ◽  
Author(s):  
Mauricio Yugo Souza ◽  
Laura Celia Fernandes Meirelles ◽  
Isabela Roberta Vieira Duque ◽  
Mariane Cintra Mailart ◽  
Taciana Marco Ferraz Caneppele ◽  
...  
Keyword(s):  
Cross Section ◽  
Chemical Elements ◽  
Human Teeth ◽  
Significance Level ◽  
X Ray ◽  
Tooth Remineralization ◽  
Human Dentin ◽  
Knoop Microhardness ◽  
Mg Content

<p><strong>Objective</strong>: The aim of this study was to assess the amount of chemical elements (Ca, O, C, P, Fe, and Mg) and the cross-section hardness of sclerotic darkened dentin in human teeth. <strong>Material</strong> <strong>and</strong> <strong>Methods</strong>: The study was approved by the local IRB and ten extracted teeth (five sound and five presenting sclerotic darkened dentin) were used. Tooth was sectioned mesiodistally and each half was used for each test. Amount of chemical elements (%w) was determined by energy dispersive X-ray spectroscopy (EDS) in three different dentin areas (shallow, medium, or deep sound or sclerotic dentin). Knoop microhardness was determined at the same EDS areas. Data were analyzed by two-way ANOVA and multiple comparison tests, with significance level at 5%. <strong>Results</strong>: No difference on microhardness was detected between sound and sclerotic dentin (p = 0.743) and also among dentin depths (p = 0.837). Lower Ca (p = 0.024) and higher C (p = 0.015) amounts were found at superficial sclerotic dentin. Increased Mg content (p &lt; 0.001) was detected in sound dentin. <strong>Conclusion</strong>: It was concluded darkened sclerotic dentin presents similar cross-section microhardness to sound dentin. The assessed chemical elements were similarly present in sound or sclerotic dentin, except for Mg, which was present higher concentration in sound dentin. Ca and P were lower in superficial sclerotic dentin.</p><p> </p><p><strong>Keywords: </strong>Dentin; Hardness; Minerals; Tooth Remineralization.</p>

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