scholarly journals Distance-Based Skeletonization on the BCC Grid

2021 ◽  
Author(s):  
Gábor Karai ◽  
Péter Kardos
Keyword(s):  
The Body ◽  
Body Centered Cubic ◽  
Thinning Algorithm ◽  
Sequential Thinning ◽  
Curve Skeletons ◽  
Novel Algorithm

Strand proposed a distance-based thinning algorithm for computing surface skeletons on the body-centered cubic (BCC) grid. In this paper, we present two modified versions of this algorithm that are faster than the original one, and less sensitive to the visiting order of points in the sequential thinning phase. In addition, a novel algorithm capable of producing curve skeletons is also reported.

Voids in Irradiated Tungsten and Molybdenum

1969 ◽  
Vol 27 ◽  
pp. 190-191
Author(s):  
Robert C. Rau ◽  
Robert L. Ladd
Keyword(s):  
Melting Point ◽  
Fast Neutron ◽  
Neutron Irradiation ◽  
Elevated Temperatures ◽  
Irradiation Temperature ◽  
The Body ◽  
Face Centered Cubic ◽  
Body Centered Cubic ◽  
Cubic Metals ◽  
Face Centered

Recent studies have shown the presence of voids in several face-centered cubic metals after neutron irradiation at elevated temperatures. These voids were found when the irradiation temperature was above 0.3 Tm where Tm is the absolute melting point, and were ascribed to the agglomeration of lattice vacancies resulting from fast neutron generated displacement cascades. The present paper reports the existence of similar voids in the body-centered cubic metals tungsten and molybdenum.

MINIMAL KNOTTING NUMBERS

2009 ◽  
Vol 18 (08) ◽  
pp. 1159-1173 ◽  
Author(s):  
CASEY MANN ◽  
JENNIFER MCLOUD-MANN ◽  
RAMONA RANALLI ◽  
NATHAN SMITH ◽  
BENJAMIN MCCARTY
Keyword(s):  
The Body ◽  
Computer Algorithm ◽  
Face Centered Cubic ◽  
Body Centered Cubic ◽  
Cubic Lattice ◽  
The Face ◽  
Face Centered ◽  
Body Centered Cubic Lattice

This article concerns the minimal knotting number for several types of lattices, including the face-centered cubic lattice (fcc), two variations of the body-centered cubic lattice (bcc-14 and bcc-8), and simple-hexagonal lattices (sh). We find, through the use of a computer algorithm, that the minimal knotting number in sh is 20, in fcc is 15, in bcc-14 is 13, and bcc-8 is 18.

Poisson's Ratio for Central-Force Polycrystals

1976 ◽  
Vol 31 (12) ◽  
pp. 1539-1542 ◽  
Author(s):  
H. M. Ledbetter
Keyword(s):  
Electron Energy ◽  
Poisson Ratio ◽  
The Body ◽  
Central Force ◽  
Face Centered Cubic ◽  
Polycrystalline Aggregate ◽  
Body Centered Cubic ◽  
The Face ◽  
Predicted Values ◽  
Face Centered

Abstract The Poisson ratio υ of a polycrystalline aggregate was calculated for both the face-centered cubic and the body-centered cubic cases. A general two-body central-force interatomatic potential was used. Deviations of υ from 0.25 were verified. A lower value of υ is predicted for the f.c.c. case than for the b.c.c. case. Observed values of υ for twenty-three cubic elements are discussed in terms of the predicted values. Effects of including volume-dependent electron-energy terms in the inter-atomic potential are discussed.

Rapid Thermal Transformation of A-15 Crystal Structure Metallic Thin Films

1995 ◽  
Vol 387 ◽  
Author(s):  
M. J. O'Keefe ◽  
C. L. Cerny
Keyword(s):  
Crystal Structure ◽  
Thin Films ◽  
Thermal Annealing ◽  
Rapid Thermal Annealing ◽  
Physical Vapor Deposition ◽  
Thermal Transformation ◽  
The Body ◽  
Cubic Phase ◽  
Body Centered Cubic ◽  
Body Center Cubic

AbstractPhysical vapor deposition of Group VI elements (Cr, Mo, W) can lead to the formation of a metastable A-15 crystal structure under certain processing conditions. Typically, a thermally induced transformation of the metastable A-15 structure into the equilibrium body centered cubic structure has been accomplished by conventional furnace annealing at T/Tm ≈ 0.3 from tens of minutes to several hours. In this study we report on the use of rapid thermal annealing to transform sputter deposited A- 15 crystal structure tungsten and chromium thin films into body centered cubic films within the same temperature range but at times on the order of one minute. The minimum annealing times and temperatures required for complete transformation of the A-15 phase into the BCC phase varied from sample to sample, indicating that the transformation was dependent on the film characteristics. The electrical resistivity of A-15 Cr and W films was measured before and after rapid thermal annealing and was found to significantly decrease after transformation into the body center cubic phase.

Textures of the Hot-Forged Ti6Al4V Alloy

2013 ◽  
Vol 203-204 ◽  
pp. 111-114
Author(s):  
Adam Bunsch ◽  
Wiktoria Ratuszek ◽  
Małgorzata Witkowska ◽  
Joanna Kowalska ◽  
Aneta Łukaszek-Sołek
Keyword(s):  
Deformation Temperature ◽  
Phase State ◽  
Hexagonal Phase ◽  
Ti6al4v Alloy ◽  
The Body ◽  
Cubic Phase ◽  
Body Centered Cubic ◽  
Two Phase ◽  
Different Temperatures

This paper presents the results of the texture investigation in the hexagonal phase and the body-centered cubic  phase of the Ti6Al4V alloy hot-deformed by forging. Forging was performed at two different temperatures on the occurrence of the single  and in the two-phase  +  state. It was found that after deformation both  and  phases are textured and their textures strongly depends on deformation temperature.

scholarly journals The Use of Infrared Spectrophotometry for Measuring Body Water Spaces

1999 ◽  
Vol 45 (7) ◽  
pp. 1077-1081 ◽  
Author(s):  
Graham Jennings ◽  
Leslie Bluck ◽  
Antony Wright ◽  
Marinos Elia
Keyword(s):  
Sample Preparation ◽  
Total Body Water ◽  
Biological Fluids ◽  
Deuterium Oxide ◽  
Body Water ◽  
The Body ◽  
Infrared Spectrophotometry ◽  
Significant Difference ◽  
Total Body ◽  
Novel Algorithm

Abstract Background: The conventional method of measuring total body water by the deuterium isotope dilution method uses gas isotope ratio mass spectrometry (IRMS), which is both expensive and time-consuming. We investigated an alternative method, using Fourier transform infrared spectrophotometry (FTIR), which uses less expensive instrumentation and requires little sample preparation. Method: Total body water measurements in human subjects were made by obtaining plasma, saliva, and urine samples before and after oral dosing with 1.5 mol of deuterium oxide. The enrichments of the body fluids were determined from the FTIR spectra in the range 1800–2800 cm−1, using a novel algorithm for estimation of instrumental response, and by IRMS for comparison. Results: The CV (n = 5) for repeat determinations of deuterium oxide in biological fluids and calibrator solutions (400–1000 μmol/mol) was found to be in the range 0.1–0.9%. The use of the novel algorithm instead of the integration routines supplied with the instrument gave at least a threefold increase in precision, and there was no significant difference between the results obtained with FTIR and those obtained with IRMS. Conclusion: This improved infrared method for measuring deuterium enrichment in plasma and saliva requires no sample preparation, is rapid, and has potential value to the clinician.

On sodium clusters in C60 fullerides

1997 ◽  
Vol 75 (1) ◽  
pp. 77-82 ◽  
Author(s):  
M. Apostol ◽  
F. Rachdi ◽  
C. Goze ◽  
L. Hajji
Keyword(s):  
Electric Charge ◽  
The Body ◽  
Electron Charge ◽  
Body Centered Cubic ◽  
Fermi Theory ◽  
Fermi Model ◽  
Thomas Fermi ◽  
Sodium Clusters ◽  
Alkali Fullerides

Sodium (Na) clusters in octahedral cages of Na-intercalated fullerides Na6C60 and Na11C60 are studied within a Thomas–Fermi model. It is shown that the tetrahedral Na4 cluster in Na6C60 has an electric charge ~ +2.7 (in electron charge units), while the body-centered cubic Na9 cluster in Na11C60 is almost electrically neutral. Keywords: sodium clusters, alkali fullerides, Thomas–Fermi theory, ionization charge.

Influence of specimen size on the mechanical properties of microlattices obtained by selective laser melting

2019 ◽  
pp. 095440621986974
Author(s):  
Matteo Gavazzoni ◽  
Laura Boniotti ◽  
Stefano Foletti
Keyword(s):  
Elastic Modulus ◽  
Selective Laser Melting ◽  
Test Procedure ◽  
Specimen Size ◽  
The Body ◽  
Image Correlation ◽  
Good Prediction ◽  
Face Centered Cubic ◽  
Body Centered Cubic ◽  
Laser Melting

A detailed study of compression tests on lattice structures obtained by selective laser melting with AlSi7Mg powder is presented here. Two different cell topologies have been investigated: the body-centered cubic cell and the face centered cubic cell or 3D Warren structure. Specimens of different volume have been printed in order to investigate the effect of the size on the mechanical response and properties of the structure. Particular attention has been paid to the definition of the test procedure and the analysis of the data to properly characterize the microlattice. No remarkable effect of the specimen size has been found in terms of elastic modulus and yielding stress. On the contrary, the maximum stress and the failure mechanism are influenced by the size of the specimen; for the body-centered cubic cell, a detailed analysis has been performed through digital image correlation of the failure. Test results have been compared with the results of an elasto-plastic simulation performed on a single cell of lattice with periodic boundary conditions, showing a good prediction in terms of elastic modulus and yielding stress.

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