3D RECONSTRUCTION OF INNER STRUCTURE OF RADIOACTIVE SAMPLES UTILIZING GAMMA TOMOGRAPHY

2019 ◽  
Vol 186 (2-3) ◽  
pp. 239-243
Author(s):  
David Zoul ◽  
Pavel Zháňal ◽  
Ladislav Viererbl ◽  
Antonín Kolros ◽  
Milan Zuna ◽  
...  
Keyword(s):  
Chemical Composition ◽  
Three Dimensional ◽  
Small Sample ◽  
Research Centre ◽  
3D Tomography ◽  
Structural Inhomogeneities ◽  
Low Dimension ◽  
Different Levels ◽  
Radionuclide Source ◽  
Fine Crack

Abstract Unique 3D tomography apparatus was built and successfully tested in Research Centre Rez. The apparatus allows three-dimensional view into the interior of low-dimension radioactive samples with a diameter up to several tens of millimeters with a betterresolution then 1 mm3 and is designed to detect domains with different levels of radioactivity. Structural inhomogeneities such as cavities, cracks or regions with different chemical composition can be detected using this equipment. The SPECT scanner has been successfully tested on several samples composed of a 3-mm radionuclide source located eccentrically within homogeneous steel bushings. To detect fine cracks inside a small sample, an ultrafine scan of the sample was carried out in the course of 24 hours with a 0.5-mm longitudinal and transverse step and 18° angular step. The exact location and orientation of a fine crack artificially formed inside a sample has been detected.

Energies and Electric Dipole Moments of the Bound Vibrational States of HN2+ and DN2+

2008 ◽  
Vol 73 (6-7) ◽  
pp. 873-897 ◽  
Author(s):  
Vladimír Špirko ◽  
Ota Bludský ◽  
Wolfgang P. Kraemer
Keyword(s):  
Dipole Moment ◽  
Nearest Neighbor ◽  
Energy Surface ◽  
Dipole Moments ◽  
Three Dimensional ◽  
Vibrational States ◽  
Spacing Distribution ◽  
Triatomic Molecules ◽  
Vibrational Levels ◽  
Different Levels

The adiabatic three-dimensional potential energy surface and the corresponding dipole moment surface describing the ground electronic state of HN2+ (Χ1Σ+) are calculated at different levels of ab initio theory. The calculations cover the entire bound part of the potential up to its lowest dissociation channel including the isomerization barrier. Energies of all bound vibrational and low-lying ro-vibrational levels are determined in a fully variational procedure using the Suttcliffe-Tennyson Hamiltonian for triatomic molecules. They are in close agreement with the available experimental numbers. From the dipole moment function effective dipoles and transition moments are obtained for all the calculated vibrational and ro-vibrational states. Statistical tools such as the density of states or the nearest-neighbor level spacing distribution (NNSD) are applied to describe and analyse general patterns and characteristics of the energy and dipole results calculated for the massively large number of states of the strongly bound HN2+ ion and its deuterated isotopomer.

scholarly journals Community intervention strategies to reduce the impact of financial strain and promote financial well-being: a comprehensive rapid review

2021 ◽  
Vol 28 (1) ◽  
pp. 42-50
Author(s):  
Nicole M. Glenn ◽  
Lisa Allen Scott ◽  
Teree Hokanson ◽  
Karla Gustafson ◽  
Melissa A. Stoops ◽  
...  
Keyword(s):  
Quality Of Life ◽  
Community Intervention ◽  
Well Being ◽  
Small Sample ◽  
Financial Strain ◽  
Rapid Review ◽  
Research Centre ◽  
Future Research ◽  
The Impact

Financial well-being describes when people feel able to meet their financial obligations, feel financially secure and are able to make choices that benefit their quality of life. Financial strain occurs when people are unable to pay their bills, feel stressed about money and experience negative impacts on their quality of life and health. In the face of the global economic repercussions of the COVID-19 pandemic, community-led approaches are required to address the setting-specific needs of residents and reduce the adverse impacts of widespread financial strain. To encourage evidence-informed best practices, a provincial health authority and community-engaged research centre collaborated to conduct a rapid review. We augmented the rapid review with an environmental scan and interviews. Our data focused on Western Canada and was collected prior to the pandemic (May–September 2019). We identified eight categories of community-led strategies to promote financial well-being: systems navigation and access; financial literacy and skills; emergency financial assistance; asset building; events and attractions; employment and educational support; transportation; and housing. We noted significant gaps in the evidence, including methodological limitations of the included studies (e.g. generalisability, small sample size), a lack of reporting on the mechanisms leading to the outcomes and evaluation of long-term impacts, sparse practice-based data on evaluation methods and outcomes, and limited intervention details in the published literature. Critically, few of the included interventions specifically targeted financial strain and/or well-being. We discuss the implications of these gaps in addition to possibilities and priorities for future research and practice. We also consider the results in relation to the COVID-19 pandemic and its economic consequences.

EFFECT OF ABRASIVE TYPE ON THE SURFACE ROUGHNESS AND MRR IN MAF OF AISI 304 STEEL

2021 ◽  
Author(s):  
MAHMUT ÇELIK ◽  
HAKAN GÜRÜN ◽  
ULAŞ ÇAYDAŞ
Keyword(s):  
Surface Roughness ◽  
Removal Rate ◽  
Three Dimensional ◽  
Steel Plates ◽  
304 Stainless Steel ◽  
Average Surface Roughness ◽  
Machining Time ◽  
Aisi 304 ◽  
Average Surface ◽  
Different Levels

In this study, the effects of experimental parameters on average surface roughness and material removal rate (MRR) were experimentally investigated by machining of AISI 304 stainless steel plates by magnetic abrasive finishing (MAF) method. In the study in which three different abrasive types were used (Al2O3, B4C, SiC), the abrasive grain size was changed in two different levels (50 and 80[Formula: see text][Formula: see text]m), while the machining time was changed in three different levels (30, 45, 60[Formula: see text]min). Surface roughness values of finished surfaces were measured by using three-dimensional (3D) optical surface profilometer and surface topographies were created. MRRs were measured with the help of precision scales. The abrasive particles’ condition before and after the MAF process was examined and compared using a scanning electron microscope. As a result of the study, the surface roughness values of plates were reduced from 0.106[Formula: see text][Formula: see text]m to 0.028[Formula: see text][Formula: see text]m. It was determined that the best parameters in terms of average surface roughness were 60[Formula: see text]min machining time with 50[Formula: see text][Formula: see text]m B4C abrasives, while the best result in terms of MRR was taken in 30[Formula: see text]min with 50[Formula: see text][Formula: see text]m SiC abrasives.

Effect of 3D printer enabled surface morphology and composition on coral growth in artificial reefs

2021 ◽  
Vol ahead-of-print (ahead-of-print) ◽  
Author(s):  
Ilse Valenzuela Matus ◽  
Jorge Lino Alves ◽  
Joaquim Góis ◽  
Augusto Barata da Rocha ◽  
Rui Neto ◽  
...  
Keyword(s):  
Additive Manufacturing ◽  
Chemical Composition ◽  
Chemical Elements ◽  
Three Dimensional ◽  
Coral Growth ◽  
Coralline Algae ◽  
Textured Surface ◽  
Crustose Coralline Algae ◽  
Statistical Parameters ◽  
Content Type

Purpose The purpose of this paper is to prove and qualify the influence of textured surface substrates morphology and chemical composition on the growth and propagation of transplanted corals. Use additive manufacturing and silicone moulds for converting three-dimensional samples into limestone mortar with white Portland cement substrates for coral growth. Design/methodology/approach Tiles samples were designed and printed with different geometries and textures inspired by nature marine environment. Commercial coral frag tiles were analysed through scanning electron microscopy (SEM) to identify the main chemical elements. Raw materials and coral species were selected. New base substrates were manufactured and deployed into a closed-circuit aquarium to monitor the coral weekly evolution process and analyse the results obtained. Findings Experimental results provided positive statistical parameters for future implementation tests, concluding that the intensity of textured surface, interfered favourably in the coralline algae biofilm growth. The chemical composition and design of the substrates were determinant factors for successful coral propagation. Recesses and cavities mimic the natural rocks aspect and promoted the presence and interaction of other species that favour the richness of the ecosystem. Originality/value Additive manufacturing provided an innovative method of production for ecology restoration areas, allowing rapid prototyping of substrates with high complexity morphologies, a critical and fundamental attribute to guarantee coral growth and Crustose Coralline Algae. The result of this study showed the feasibility of this approach using three-dimensional printing technologies.

scholarly journals Preclinical Ultrasound-Guided Photoacoustic Imaging of the Placenta in Normal and Pathologic Pregnancy

2018 ◽  
Vol 17 ◽  
pp. 153601211880272 ◽  
Author(s):  
Liliya M. Yamaleyeva ◽  
K. Bridget Brosnihan ◽  
Lane M. Smith ◽  
Yao Sun
Keyword(s):  
Oxygen Saturation ◽  
Early Identification ◽  
Photoacoustic Imaging ◽  
Three Dimensional ◽  
Normal Pregnancy ◽  
Preclinical Study ◽  
Ultrasound Guided ◽  
3 Dimensional ◽  
Sensitive Tool ◽  
Different Levels

Placental oxygenation varies throughout pregnancy. The detection of early changes in placental oxygenation as pregnancy progresses is important for early identification of preeclampsia or other complications. This invited commentary discusses a recent preclinical study on the application of 3-dimensional photoacoustic imaging (PAI) for assessment of regional variations in placental oxygenation and longitudinal analysis of differences in placental oxygenation throughout normal pregnancy and pregnancy associated with hypertension or placental insufficiency in mice. Three-dimensional PAI more accurately reflects oxygen saturation, hemoglobin concentrations, and changes in oxygen saturation in whole placenta compared to 2-dimensional imaging. These studies suggest that PAI is a sensitive tool to detect different levels of oxygen saturation in the placental and fetal vasculature in pathologic and normal pregnancy in mice.

scholarly journals Effect of shoot topping intensity on 'Cabernet Franc' grapevine maturity in high-altitude region

2017 ◽  
Vol 52 (10) ◽  
pp. 946-950
Author(s):  
Douglas André Würz ◽  
José Luiz Marcon Filho ◽  
Alberto Fontanella Brighenti ◽  
Ricardo Allebrandt ◽  
Betina Pereira de Bem ◽  
...  
Keyword(s):  
Chemical Composition ◽  
Leaf Area ◽  
Soluble Solids ◽  
Anthocyanin Content ◽  
Total Polyphenol ◽  
Cabernet Franc ◽  
Grape Berries ◽  
Grape Quality ◽  
Vegetative Canopy ◽  
Different Levels

Abstract: The objective of this work was to evaluate the chemical composition of 'Cabernet Franc' grape subjected to different levels of shoot topping. The experiment was conducted in the 2008 and 2009 vintages, and the levels of shoot topping consisted of: control, without topping; and reductions of 15, 30, and 45% in total leaf area. The effect of shoot topping intensity on the chemical composition of the 'Cabernet Franc' grape berries was observed. A reduction of 26% in the vegetative canopy through a moderate shoot topping increased the total polyphenol index and the anthocyanin content. Shoot topping is a practice that must be carried out with caution, since severe shoot topping, i.e., a reduction greater than 26% of the leaf area, may negatively impact grape quality by reducing the content of soluble solids and decreasing the total polyphenol index and the content of anthocyanins of 'Cabernet Franc' grape berries.

scholarly journals Discrimination of Genealogical Groups of Arabica Coffee by the Chemical Composition of the Beans

2019 ◽  
Vol 11 (16) ◽  
pp. 141
Author(s):  
Larissa O. Fassio ◽  
Marcelo R. Malta ◽  
Gladyston R. Carvalho ◽  
Antônio A. Pereira ◽  
Ackson D. Silva ◽  
...  
Keyword(s):  
Fatty Acids ◽  
Chemical Composition ◽  
Chemical Markers ◽  
Total Lipids ◽  
Germplasm Bank ◽  
Total Sugars ◽  
Coffee Beans ◽  
Different Levels ◽  
Important Marker

This work aimed to characterize and discriminate genealogical groups of coffee as to the chemical composition of the grains through the model created by PLS-DA method. 22 accessions of Coffea arabica, from the Active Germplasm Bank of Minas Gerais, were divided into groups according to the genealogical origin. Samples of ripe fruits were harvested selectively and processed by the wet method, to obtain pulped coffee beans, with 11% (b.u.) of water content. The raw beans were assessed as to the content of polyphenols, total sugars, total lipids, protein, caffeine, sucrose, and fatty acids. The data were submitted the chemometric analysis, PCA and PLS-DA. The results of PLS-DA identified the variables which most influence the classification of genealogical groups and possible chemical markers to accessions processed by the pulped method. The sucrose content was an important marker for the Exotic accession group. However, the content of polyphenols has been identified as a marker for the group Tymor Hybrid, and the caffeine for the bourbon group. The different fatty acids have been identified as markers for all genealogical groups, at different levels. The model PLS-DA is effective in discriminating genealogical groups from the chemical composition of the beans.

scholarly journals Geomorphometric analysis of cave ceiling channels mapped with 3D terrestrial laser scanning

2016 ◽  
Author(s):  
Michal Gallay ◽  
Zdenko Hochmuth ◽  
Ján Kaňuk ◽  
Jaroslav Hofierka
Keyword(s):  
Laser Scanning ◽  
Methodological Approach ◽  
Three Dimensional ◽  
Terrestrial Laser Scanning ◽  
Scalar Fields ◽  
Complex Environments ◽  
Digital Elevation ◽  
Unique Manner ◽  
Elevation Model ◽  
Different Levels

Abstract. The change of hydrological conditions during the evolution of caves in carbonate rocks often results in a complex subterranean geomorphology which comprises specific landforms such as ceiling channels, anastomosing half tubes, or speleothems organised vertically in different levels. Studying such complex environments traditionally requires tedious mapping, however, this is being replaced with terrestrial laser scanning technology. Laser scanning overcomes the problem of reaching high ceilings providing new options to map underground landscapes with unprecedented level of detail and accuracy. The acquired point cloud can be handled conveniently with dedicated software, but applying traditional geomorphometry to analyse the cave surface is limited. This is because geomorphometry has been focused on parameterisation and analysis of surficial terrain. The theoretical and methodological concept has been based on two-dimensional scalar fields which is sufficient for most cases of the surficial terrain. The terrain surface is modelled with a bivariate function of altitude (elevation) and represented by a raster digital elevation model. However, the cave is a three-dimensional entity therefore a different approach is required for geomorphometric analysis. In this paper, we demonstrate the benefits of high resolution cave mapping and 3-D modelling to better understand the palaeohydrography of the Domica cave in Slovakia. This methodological approach adopted traditional geomorphometric methods in a unique manner and also new methods used in 3D computer graphics which can be applied to study other 3-D geomorphological forms

Time Domain Computation of the Wave-Making Resistance of Ships

2005 ◽  
Vol 49 (02) ◽  
pp. 144-158 ◽  
Author(s):  
F. Kara ◽  
D. Vassalos
Keyword(s):  
Steady State ◽  
Time Domain ◽  
Three Dimensional ◽  
Impulse Response Function ◽  
The Body ◽  
Source Distribution ◽  
Research Centre ◽  
Surface Source ◽  
Calm Water ◽  
Marine Engineering

The Ship Stability Research Centre, Department of Naval Architecture and Marine Engineering, The Universities of Glasgow and Strathclyde, Scotland, UKA linearized three-dimensional potential flow formulation in time domain is applied to calculate wave-making resistance of ships in calm water. Steady-state perturbation potentials for resistance are obtained as the steady-state limit of the surge radiation impulse response function using the transient free surface source distribution over the body surface. Five different vessels are used to validate the present numerical approximation. The results, including steady-state wave-making resistance, sinkage force, trim moment, and wave profile along the waterline, are compared with other published numerical and experimental results.

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