scholarly journals DETERMINATION OF THE 234U ISOTOPE CONTENT IN URANIUM-BEARING MATERIALS USING HIGH-RESOLUTION GAMMA SPECTROMETRY

2021 ◽  
pp. 81-85
Author(s):  
D.V. Kutniy ◽  
D.D. Burdeinyi ◽  
N.N. Savchenko
Keyword(s):  
Standard Samples ◽  
Physical Chemical ◽  
Alternative Approach ◽  
Wide Range ◽  
Bearing Materials ◽  
Intrinsic Efficiency ◽  
Non Destructive ◽  
High Resolution Gamma Spectrometry ◽  
Isotope Content

The paper presents an overview of the research into the available non-destructive methods of determining the 234U isotope content in uranium-bearing materials. An alternative approach to a problem of detector calibration by the characteristic “intrinsic” efficiency is proposed. Certified reference uranium-bearing materials CRM 969 and CRM 146 (a range of 235U enrichments studied was 0.3…93%) were used as test samples, measurements were carried out with a wide-range energy detector based on the high-purity BeGe 3830 germanium (Canberra, USA) with 38 cm2 area and 3 cm thickness. An approach used for the “intrinsic” efficiency calibration for the 234U analysis permits to decrease the measurement error to 7.5% in the whole range of 235U enrichment (from 0.3 to 93%) and 234U concentrations (20 to 9800 µg/g). The proposed method does not demand standard samples for equipment calibration and does not depend on the physical (chemical) form of the investigated material and measurement geometry.

scholarly journals Determination of 234U isotope in uranium-bearing materials by high-resolution gamma-spectrometry

2018 ◽  
pp. 41-46
Author(s):  
D. V. Kutnii
Keyword(s):  
Measurement Error ◽  
Standard Samples ◽  
Software Products ◽  
Isotopic Analyses ◽  
Absolute Efficiency ◽  
Bearing Materials ◽  
Intrinsic Efficiency ◽  
Enriched Uranium ◽  
Isotope Content

The paper presents research of the existing methods of non-destructive quantitative determination of 234U isotope content in uranium bearingmaterials. Also alternative method is proposed, which is based on the approach of detector calibration on “intrinsic” efficiency. The method is based on finding the ratio of the 234U and 235U isotopes activities using their most intense gamma lines in the energy range of 120...210 keV and as a consequence does not require an estimate of the absolute efficiency of registration of the gamma detector. Certified reference standard samples of uranium-bearing materials CRM 969 and CRM 146 were used as research samples (interval of investigated enrichments on 235U 0,3…93 %), measurements were performed by means of broad-energy detector based on high-purity germanium BeGe 3830 (Canberra, USA) with area 36 cm2 and thickness 3 cm. It was shown that using of the up-to-date software products for isotopic analyses of uranium (MGAU, FRAM) it is difficult to perform of reliable estimation of 234U isotope content in depleted and natural samples due to significant measurement error (from 35 % to 100 %). In case of analyses of enriched uranium the software code MGAU systematically underestimates the content of 234U on 20…30 %. Use of alternative approach for calibration of detector on “intrinsic” efficiency for analyses of 234U results in decrease of measurement error up to 7,5 % in the whole range of enrichment on 235U (0,3…93 %) and investigated concentrations of 234U (20…9800 μg/g). The proposed method does not demand standard samples for equipment calibration and not depend on physical (chemical) form of investigated material and geometry of measurements.

scholarly journals PHYSICAL-CHEMICAL FORMATION CONDITIONS OF URANIUM-TITANIUM-METAGEL MINERALIZATION AT THE GOLD-URANIUM ELKON DEPOSIT

2017 ◽  
pp. 52-57 ◽  
Author(s):  
M. M. Komarova ◽  
VL. B. Komarov ◽  
A. P. Aleshin ◽  
T. L. Krylova
Keyword(s):  
Crystalline Form ◽  
Fluid Regime ◽  
Ore Formation ◽  
Physical Chemical ◽  
Wide Range ◽  
Moderate Salinity ◽  
Formation Conditions ◽  
Carbonate Composition ◽  
Main Factor

A wide range of the temperatures of hydrothermal fluid regime (430-103 °C) has been revealed in the result of microthermometric study of the fluid inclusions in the minerals of pre-ore and post-ore stages developed at the Elkon deposit. Average temperatures, as well as the temperature variation are similar for both pre-ore and post-ore stages. It allows sure determination of temperatures of uranium ore formation as 400-120 °C. Fluids possessed Na-chloride, rarely Na-chloride-carbonate composition and moderate salinity (6-16 wt. % · NaCl equiv.). The wide range of tem-peratures confirms an assumption made before that various temperatures were the reason of formation of uranium mineralization both in the form of predominantly amorphous phase (U-Ti-metagel), as well as the rarely crystalline form (brannerite). Abrupt temperature decrease was apparently the main factor of the ore precipitation.

Extremely Light Weight Rheocast Components for Automotive Space Frame

2012 ◽  
Vol 192-193 ◽  
pp. 545-550 ◽  
Author(s):  
Mario Rosso ◽  
Ildiko Peter ◽  
Gianluigi Chiarmetta ◽  
Ivano Gattelli
Keyword(s):  
High Performance ◽  
Mechanical Tests ◽  
Standard Samples ◽  
Fe Content ◽  
Wide Range ◽  
Automotive Parts ◽  
Fracture Surface Analysis ◽  
High Level ◽  
Non Destructive ◽  
Very High

This paper presents an analysis of a new rheocasting process suitable for the manufacturing of high performance automotive parts. The process is able for the realization of components using Al alloys. An important aspect is related to the possibility to obtain quite wide range of thicknesses, starting from 2.5 mm. The used alloy is the well known A356, with low Fe content, maximum 0.08 wt%. T6 heat treatments has been performed, while the soundness of the parts has been certified by non destructive tests. These parts are produced to be mounted on a top level and famous sport car. Non standard samples for mechanical tests have been machined directly from the components. Following the mechanical tests fracture surface analysis has been carried out by SEM to observe some morphological details and to evaluate the influence of the process and of the alloy conditions on the fracture behaviour. On the polished transverse sections of the samples morphological analysis has been performed. The obtained results shown high level of mechanical strength for all series of components. The reliability of the process is very high at a convenient level of manufacturing rate. The weldability of the parts has been demonstrated.

scholarly journals Quantitative Analysis of Asbestos-Containing Materials Using Various Test Methods

Minerals ◽  
2020 ◽  
Vol 10 (6) ◽  
pp. 568
Author(s):  
Kiho Yang ◽  
Kyu-Cheul Yoo ◽  
Jaewoo Jung
Keyword(s):  
Electron Microscopy ◽  
Test Methods ◽  
Standard Samples ◽  
Fibrous Minerals ◽  
Transmission Electron ◽  
Low Costs ◽  
Non Destructive ◽  
Mineral Identification ◽  
Xrpd Analysis

The advantages of X-ray powder diffraction (XRPD) analysis are its non-destructive nature, reliability, fast and easy sample preparation, and low costs. XRPD analysis has been used for mineral identification and the quantitative/qualitative determination of various types of fibrous minerals in asbestos-containing materials (ACMs). In order to test the detection limit of ACMs by XRPDD, standard samples with various concentrations of ACMs (0.1%, 1%, and 3%) were fabricated using three matrix materials (talc, vermiculite, and sepiolite). Asbestiform tremolite and chrysotile were identified in the XRPD profiles of the samples with 1% and 3% ACMs. Their integral intensities were positively correlated with the concentrations. However, the XRPD peak of asbestos was not found in the samples with 0.1% ACMs. Therefore, scanning and transmission electron microscopy were utilized to investigate the samples with a very low concentration of ACMs. Although the ACM concentration (0.1%) was negligible and its direct observation was time-consuming, electron microscopy allowed for the detection of asbestos in several matrix materials. Thus, a combination of XRPD and electron microscopy improve analytical performance and data reliability.

scholarly journals Reviews and syntheses: Gaining insights into evapotranspiration partitioning with novel isotopic monitoring methods

2020 ◽  
Author(s):  
Youri Rothfuss ◽  
Maria Quade ◽  
Nicolas Brüggemann ◽  
Alexander Graf ◽  
Harry Vereecken ◽  
...  
Keyword(s):  
Land Surface ◽  
Monitoring Methods ◽  
Current State ◽  
Wide Range ◽  
Stable Isotopic ◽  
Land Surface Modelling ◽  
High Vertical Resolution ◽  
State Of Research ◽  
Non Destructive

Abstract. Disentangling ecosystem evapotranspiration (ET) into evaporation (E) and transpiration (T) is of high relevance for a wide range of applications, from land surface modelling to policy making. Identifying and analysing the determinants of the ratio of T to ET (T / ET) for various land covers and uses, especially in view of climate change with increased frequency of extreme events (e.g., heatwaves and floods), is prerequisite for forecasting the hydroclimate of the future and tackling present issues, such as agricultural and irrigation practices. A powerful partitioning method consists in determining the water stable isotopic compositions of ET, E, and T (δET, δE, and δT, respectively) from the water retrieved from the atmosphere, the soil, and the plant vascular tissues. The present work emphasises the challenges this particular method faces (e.g., the spatial and temporal representativeness of the T / ET estimates, the limitations of the models used and the sensitivities to their driving parameters) and the progress that needs to be made in light of the recent methodological developments. As our review is intended for a broader audience beyond the isotopic ecohydrological and micrometeorological communities, it also attempts to provide a thorough review of the ensemble of techniques used for determining δET, δE, and δT, and solving the partitioning equation for T / ET. From the current state of research, we conclude that the most promising way forward to ET partitioning and capturing the sub-daily dynamics of T / ET is in making use of non-destructive online monitoring techniques of the stable isotopic composition of soil and xylem water. Effort should continue towards the application of the eddy covariance technique for high-frequency determination of δET at the field scale as well as the concomitant determination of δET, δE, and δT at high vertical resolution with field-deployable lift systems.

scholarly journals Postharvest behavior and lycopene content of tomatoes at different harvest times

2020 ◽  
Vol 42 ◽  
pp. e48403
Author(s):  
Denise Candido Gonçalves ◽  
Cristiane Maria Ascari Morgado ◽  
Edson Pablo Silva ◽  
Gilmarcos de Carvalho Correa ◽  
Abadia dos Reis Nascimento ◽  
...  
Keyword(s):  
Storage Time ◽  
Titratable Acidity ◽  
Soluble Solids ◽  
Ambient Conditions ◽  
Physical Chemical ◽  
Red Color ◽  
Lycopene Content ◽  
Future Work ◽  
Non Destructive

The objective of this study was to evaluate the physical, chemical and bioactive behavior of the tomatoes of the commercialized tomato at the Central of Supply of Goiás at different times of the year and stored for 15 days in ambient conditions and propose the construction of a model to estimate the content of lycopene from the coloring of the fruits. Seven monthly collections of tomatoes were carried out between February and August. The fruits were evaluated for color, firmness, fresh weight loss, titratable acidity, pH, soluble solids, lycopene, total extractable polyphenols, and antioxidant activity. The variation of brightness and firmness were inversely proportional to the storage time. The linear regression model generated from the correlation between the red color and the lycopene content can be used to estimate the lycopene value of the fruits. Future work may be carried out for developing non-destructive models of determination of lycopene for industrial tomato.

scholarly journals Moisture Damage in Ancient Masonry: A Multidisciplinary Approach for In Situ Diagnostics

Minerals ◽  
2021 ◽  
Vol 11 (4) ◽  
pp. 406
Author(s):  
Noemi Proietti ◽  
Paola Calicchia ◽  
Francesco Colao ◽  
Sara De Simone ◽  
Valeria Di Tullio ◽  
...  
Keyword(s):  
Holistic Approach ◽  
Point Of View ◽  
Moisture Distribution ◽  
Non Invasive ◽  
Unilateral Nmr ◽  
Moisture Effects ◽  
Wide Range ◽  
Non Destructive

San Nicola in Carcere, one of the minor basilicas in the historical center of Rome, was the location of a wide investigation campaign of the water-related deterioration causes, present in the lower sector of the apse and adjacent pillars, affected by water infiltrations, mould and salt efflorescence. The results obtained identify the presence of water content and related effects mainly on the sides of the apsidal wall. This work focuses on the use of five Non-Destructive Techniques (NDT) and intends to show the gains obtained by integrating widely interdisciplinary methods, namely the Infrared Thermography (IRT), the Unilateral Nuclear Magnetic Resonance (Unilateral NMR), the Acoustic Tomography (AT), the Acoustic Imaging (AI) and the Laser-Induced Fluorescence (LIF). All the techniques contribute to the rapid, non-invasive and early identification of the moisture distribution, while some of them (LIF and AI) also address the determination of some moisture effects. The integrated use of different techniques helps to take the multidisciplinary point of view necessary to formulate an effective restoration intervention based on a sound scientific rationale; nonetheless, it allows to experiment a holistic approach, verifying the potential of a wide range of NDTs available within the context of a restoration yard.

Determination of Coating Thickness Using Impulse Excitation and Laser Measurements

2015 ◽  
Vol 801 ◽  
pp. 323-327
Author(s):  
Liviu Bereteu ◽  
Eva Nyaguly ◽  
Gheorghe Drăgănescu ◽  
Dorin Simoiu
Keyword(s):  
Coating Thickness ◽  
Surface Coating ◽  
The Other ◽  
Laser Measurements ◽  
Physical Chemical ◽  
Impulse Excitation ◽  
Development And Validation ◽  
Non Destructive ◽  
Destructive Methods

Coating is an application of a surface finish to another material and it provides the surfaces of manufactured parts with a number of desirable physical, chemical, and appearance qualities. Nearly all manufactured or fabricated products made of metal or having metal components have some types of surface coating. The coating increases sturdiness, prevents corrosion, provides hardness, or gives an attractive finish to an object. The amount of coating applied to a material, that is, the coating thickness, is crucial to the product’s final use and cost. On the other hand, in the case of surfaces subjected to wear, the same thickness is very important in the life of the product. There are several non-destructive methods of measuring coating thickness. The aim of this paper is the development and validation of an impulse excitation technique and laser measurements to determine coating thickness of metallic or nonmetallic surface.

scholarly journals Enrichment determination of low – enriched uranium material by gamma spectroscopic method

2014 ◽  
Vol 4 (2) ◽  
pp. 1-6
Author(s):  
Van Loat Bui ◽  
Van Quan Nguyen ◽  
Tuan Anh Le ◽  
Van Bay Nguyen ◽  
Thi Hong Bui ◽  
...  
Keyword(s):  
Spectroscopic Method ◽  
Efficiency Calibration ◽  
Uranium Enrichment ◽  
Activity Ratios ◽  
Intrinsic Efficiency ◽  
Enriched Uranium ◽  
Non Destructive ◽  
Good Agreement

In this work the non - destructive gamma spectroscopic method for determination of uranium enrichment is presented. In order to determine the uranium enrichment the activity ratios of 234U/235U and 238U/235Uwere measured. The activity ratios234U/235U and 238U/235U were determined by using intrinsic efficiency calibration. As a test of this method, low - enriched uranium standard was measured, the obtained result was in good agreement with the estimated value.

scholarly journals Reviews and syntheses: Gaining insights into evapotranspiration partitioning with novel isotopic monitoring methods

2021 ◽  
Vol 18 (12) ◽  
pp. 3701-3732
Author(s):  
Youri Rothfuss ◽  
Maria Quade ◽  
Nicolas Brüggemann ◽  
Alexander Graf ◽  
Harry Vereecken ◽  
...  
Keyword(s):  
Land Surface ◽  
Monitoring Methods ◽  
Current State ◽  
Wide Range ◽  
Stable Isotopic ◽  
Land Surface Modelling ◽  
High Vertical Resolution ◽  
State Of Research ◽  
Non Destructive

Abstract. Disentangling ecosystem evapotranspiration (ET) into evaporation (E) and transpiration (T) is of high relevance for a wide range of applications, from land surface modelling to policymaking. Identifying and analysing the determinants of the ratio of T to ET (T/ET) for various land covers and uses, especially in view of climate change with an increased frequency of extreme events (e.g. heatwaves and floods), is prerequisite for forecasting the hydroclimate of the future and tackling present issues, such as agricultural and irrigation practices. One partitioning method consists of determining the water stable isotopic compositions of ET, E, and T (δET, δE, and δE, respectively) from the water retrieved from the atmosphere, the soil, and the plant vascular tissues. The present work emphasizes the challenges this particular method faces (e.g. the spatial and temporal representativeness of the T/ET estimates, the limitations of the models used, and the sensitivities to their driving parameters) and the progress that needs to be made in light of the recent methodological developments. As our review is intended for a broader audience beyond the isotopic ecohydrological and micrometeorological communities, it also attempts to provide a thorough review of the ensemble of techniques used for determining δET, δE, and δE and solving the partitioning equation for T/ET. From the current state of research, we conclude that the most promising way forward to ET partitioning and capturing the subdaily dynamics of T/ET is by making use of non-destructive online monitoring techniques of the stable isotopic composition of soil and xylem water. Effort should continue towards the application of the eddy covariance technique for high-frequency determination of δET at the field scale as well as the concomitant determination of δET, δE, and δE at high vertical resolution with field-deployable lift systems.

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