scholarly journals The Santaló point for the Holmes-Thompson boundary area

2021 ◽  
pp. 108118
Author(s):  
Florent Balacheff ◽  
Gil Solanes ◽  
Kroum Tzanev
Keyword(s):  
Boundary Area

The observation of solutions in Ni3Nb

1988 ◽  
Vol 46 ◽  
pp. 540-541
Author(s):  
Z.M. Wang ◽  
J.P. Zhang
Keyword(s):  
Electron Microscopy ◽  
High Resolution ◽  
Phase Modulation ◽  
High Resolution Electron Microscopy ◽  
Antiphase Domain ◽  
Boundary Area ◽  
Matrix Type ◽  
Resolution Electron ◽  
Domain Boundaries ◽  
Kontorova Model

High resolution electron microscopy reveals that antiphase domain boundaries in β-Ni3Nb have a hexagonal unit cell with lattice parameters ah=aβ and ch=bβ, where aβ and bβ are of the orthogonal β matrix. (See Figure 1.) Some of these boundaries can creep “upstairs” leaving an incoherent area, as shown in region P. When the stepped boundaries meet each other, they do not lose their own character. Our consideration in this work is to estimate the influnce of the natural misfit δ{(ab-aβ)/aβ≠0}. Defining the displacement field at the boundary as a phase modulation Φ(x), following the Frenkel-Kontorova model [2], we consider the boundary area to be made up of a two unit chain, the upper portion of which can move and the lower portion of the β matrix type, assumed to be fixed. (See the schematic pattern in Figure 2(a)).

High-resolution microscopy of twin boundaries in gold

1987 ◽  
Vol 45 ◽  
pp. 260-261
Author(s):  
William Krakow ◽  
David A. Smith
Keyword(s):  
High Resolution ◽  
Specimen Preparation ◽  
Gold Films ◽  
Boundary Area ◽  
Transmission Electron ◽  
Recent Developments ◽  
Tilt Boundaries ◽  
High Resolution Microscopy ◽  
Twist Boundaries

Recent developments in specimen preparation, imaging and image analysis together permit the experimental determination of the atomic structure of certain, simple grain boundaries in metals such as gold. Single crystal, ∼125Å thick, (110) oriented gold films are vapor deposited onto ∼3000Å of epitaxial silver on (110) oriented cut and polished rock salt substrates. Bicrystal gold films are then made by first removing the silver coated substrate and placing in contact two suitably misoriented pieces of the gold film on a gold grid. Controlled heating in a hot stage first produces twist boundaries which then migrate, so reducing the grain boundary area, to give mixed boundaries and finally tilt boundaries perpendicular to the foil. These specimens are well suited to investigation by high resolution transmission electron microscopy.

Can the mass balance of the entire glacier area of the Tien Shan be estimated?

1992 ◽  
Vol 16 ◽  
pp. 173-179
Author(s):  
M.B. Dyurgerov ◽  
M.G. Kunakhovitch ◽  
V.N. Mikhalenko ◽  
A. M. Sokalskaya ◽  
V. A. Kuzmichenok
Keyword(s):  
Mass Balance ◽  
Vertical Profile ◽  
River Basins ◽  
Annual Runoff ◽  
Snow Accumulation ◽  
Tien Shan ◽  
Exponential Dependence ◽  
Glacier Area ◽  
Equilibrium Line Altitude ◽  
Boundary Area

The total area of glacierization of the Tien Shan in the boundary area of the USSR is about 8000 km2. The computation of mass balance was determined for this area in 12 river basins.In computation procedure, the vertical profile of snow accumulation in these regions and exponential dependence of variation of ablation with altitude are used. Thus the mass balance in each basin, bn, was calculated on the basis of these curves and represented in its relation with the equilibrium line altitude (ELA). It is shown that the relation ELA = f(bn) is linear when the range of bn values is close to zero, and in all altitude intervals this relation can be described by hypsographic curves, in all basins bn positive up to an ELA elevation of 3450 to 3500 m a.s.l. For average annual altitude of ELA, bn is negative for all regions. So the glaciers of these mountains add about 4 km3 of water to the total annual runoff.

Grain Size Modification by Micro Rotary Swaging

2015 ◽  
Vol 651-653 ◽  
pp. 627-632 ◽  
Author(s):  
Svetlana Ishkina ◽  
Bernd Kuhfuss ◽  
Christian Schenck
Keyword(s):  
Grain Size ◽  
Longitudinal Section ◽  
Forming Process ◽  
Boundary Area ◽  
Cold Forming ◽  
Flat Surfaces ◽  
Rotary Swaging ◽  
2D Simulation ◽  
Physical Tests ◽  
Formed Part

Rotary swaging is a well established cold forming process e.g. in the automotive industry. In order to modify the material properties by swaging systematically, a new process of swaging with asymmetrical strokes of the forming dies is investigated. The newly developed tools feature flat surfaces and do not represent the geometry of the formed part as in conventional swaging. Numerical simulation and physical tests are carried out with special regard to the resulting geometry, mechanical properties and the microstructure. During these tests copper wires with diameter d0=1 mm are formed. Regarding the microstructure in the longitudinal section of formed specimens, elongation of grains in the central part and grain size reduction in the boundary area are observed. Furthermore, this approach opens up new possibilities to configure the geometry of wires. 2D-simulation is applied and discussed in the paper to investigate change of the processed geometry (cross-section) and shear strain distribution during the rotary swaging process.

An online tripping index to improve microgrid dynamic stability based on estimating critical boundary area

2021 ◽  
pp. 100520
Author(s):  
Amir Habibzadeh ◽  
Mahmoud Samiei Moghaddam ◽  
Seyyed Javad Mohammadi Baygi ◽  
Soheil Ranjbar
Keyword(s):  
Dynamic Stability ◽  
Boundary Area ◽  
Critical Boundary

Boundary area in the Demon Slayer : Birth of Daisho Monogatari

2021 ◽  
Vol 79 ◽  
pp. 137-159
Author(s):  
LeeJin Park ◽  
ByeongJin Kim
Keyword(s):  
Boundary Area

scholarly journals INVESTIGATION OF HEAT DISTRIBUTION PROCESSES ON THE INNER SURFACE OF THE ENCLOSING STRUCTURE, TAKING INTO ACCOUNT THE MOVEMENT OF AIR IN THE BOUNDARY AREA BETWEEN THE DEVICE AND FENCING

2019 ◽  
Vol 16 (32) ◽  
pp. 345-361
Author(s):  
B. A. UNASPEKOV ◽  
Z. O. ZHUMADILOVA ◽  
S. S. AUELBEKOV ◽  
A. S. TAUBALDIEVA ◽  
G. B. ALDABERGENOVA
Keyword(s):  
Stokes Equations ◽  
Outer Wall ◽  
Conjugate Problem ◽  
Navier Stokes ◽  
Geometrical Parameters ◽  
Downward Flow ◽  
Navier Stokes Equations ◽  
Boundary Area ◽  
Air Mass ◽  
Hydrodynamic Motion

A study was made of the nature of the movement of air mass in the space between the device that warms the room and the confining outer wall of the room. The hydrodynamic motion of the air mass was simulated on the basis of the two-dimensional in space Navier-Stokes equations and the convective heat conduction equation to find out a detailed picture of the physical processes that occur. Also for some particular cases, analytical solutions were obtained for the conjugate problem, where the movement of air is caused by its thermal expansion and the action of gravity in areas with different densities (Archimedes' forces). The simulation of more complex types of air movement with the formation of vortex flows using numerical methods and the corresponding program codes written in C++. It was found that the movement of air mass in the space between the device and the fence strongly depends not only on the temperature of the device, the wall, and the outside air. It was revealed that hydrodynamics and heat transfer are significantly influenced by two geometrical parameters: the distance between the device and the wall, and the distance from the flooring to the bottom of the device. In particular, a thin layer of the downward flow of cold air along the fence and above the floor is possible. The condition for the occurrence of such a downward flow has been found, it is determined by the ratio of the temperature of the wall, the device, and the average temperature in the room.

scholarly journals Distribution patterns and conservation status of Crocus species in Iran, one of the diversity centers of Crocus in the Middle East

2021 ◽  
Vol 48 (2) ◽  
pp. 156-168
Author(s):  
Melika Tabasi ◽  
Ahmadreza Mehrabian ◽  
Sadaf Sayadi
Keyword(s):  
Middle East ◽  
Conservation Status ◽  
Distribution Patterns ◽  
Field Studies ◽  
Distribution Data ◽  
Herbarium Specimens ◽  
Distribution Centers ◽  
Boundary Area ◽  
Universal Transverse Mercator ◽  
Western Asia

Abstract Assessing distribution patterns of valuable taxa plays an important role in the biodiversity conservation of these taxa. The genus Crocus L. (Iridaceae) comprises about 100 species that are distributed mainly in the Mediterranean region and western Asia. The present study purposed to assess the distribution patterns of Iranian Crocus species (including C. sativus L. and 8 wild species) and their conservation status in Iran as one of diversity centers of Crocus in the Middle East. A set of geographic distribution data was compiled through field studies, and reviews of herbarium specimens, iNaturalist, and various Flora. Localities were marked on geo-referenced maps (1/106) of Iran using ArcView version 3.2 (Esri, 2000). The distribution patterns of the taxa were mapped per 0.25° × 0.25° universal transverse Mercator grid cells (25 km2 with the exception of boundary area). Based on the species distribution (SDI) (33%) and species specialization (SSI) (44%) indices, those Iranian Crocus species that are threatened are mainly distributed in Irano-Turanian region. The mountainous ecosystems of Almeh and Western Alborz are important distribution centers of these taxa. Iranian Crocus species with SSI < 0.5 (C. almehensis, C. gilanicus, C. michelsonii, and C. caspius) have the highest conservation value.

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