Thermal deformation and polymorphic transitions of 1,1-diamino-2,2-dinitroethylene in the temperature range from 145 to 475 K

In the present work, thermal expansion coefficients of a number of organic coatings were studied by a non-destructive technique (NDT) known as shearography. An organic coating, i.e., epoxy, on a metallic alloy, i.e., carbon steels, was investigated at a temperature range simulating the severe weather temperatures in Kuwait especially between the daylight and the night time temperatures, 20-60 0C. The investigation focused on determining the in-plane displacement of the coating, which amounts to the thermal deformation (strain ) with respect to the applied temperature range. Along with the experimental data, a mathematical relationship was derived describing the thermal deformation of a coated film as a function of temperature. Furthermore, results of shearography indicate that the technique is very useful NDT method not only for determining the thermal expansion coefficients of different coatings, but also the technique can be used as a 2Dmicroscope for monitoring the deformation of the coatings in real-time at a submicroscopic scale.

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Polymorphic transitions of ice at a pressure up to 2500 MPa in the temperature range 90–300 K

Crystal Research and Technology ◽

10.1002/crat.2170230503 ◽

1988 ◽

Vol 23 (5) ◽

pp. 595-603 ◽

Cited By ~ 4

Author(s):

N. N. Sirota ◽

T. B. Bizhighitov

Keyword(s):

Polymorphic Transitions ◽

Temperature Range

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Measurement of Thermal Expansion Coefficients of a Thin Film of Different Ceramic Coatings by Shearography

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.334-335.529 ◽

2007 ◽

Vol 334-335 ◽

pp. 529-532 ◽

Cited By ~ 2

Author(s):

Khaled Habib

Keyword(s):

Thermal Expansion ◽

Thermal Deformation ◽

Ceramic Coatings ◽

Carbon Steels ◽

Mathematical Relationship ◽

Night Time ◽

Temperature Range ◽

Thermal Expansion Coefficients ◽

Expansion Coefficients ◽

Plane Displacement

In the present work, thermal expansion coefficients of a number of ceramic coatings were studied by a non-destructive technique (NDT) known as shearography. Ceramic coatings, i.e., a white enamel and a yellow Acrylic Lacquer on a metallic alloy, i.e., carbon steels, were investigated at a temperature range simulating the severe weather temperatures in Kuwait, especially between the daylight and the night time temperatures, 20-60 0C. The investigation was focused on determining the in-plane displacement of the coating, which corresponds to the thermal deformation (strain), with respect to the applied temperature range. A mathematical relationship was derived along with the experimental data. The mathematical relationship described the thermal deformation of a coated film as a function of temperature. Furthermore, results of shearography indicate that the technique is found very useful NDT method not only for determining the thermal expansion coefficients of different coatings, but also the technique can be used as a 2D- microscope for monitoring the deformation of various coatings in at a submicroscopic scale.

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Concomitant cocrystal and salt: no interconversion in the solid state

Acta Crystallographica Section C Structural Chemistry ◽

10.1107/s2053229619001372 ◽

2019 ◽

Vol 75 (3) ◽

pp. 313-319

Author(s):

Evgeniy A. Losev ◽

Elena Boldyreva

Keyword(s):

Phase Transition ◽

Chemical Composition ◽

Solid State ◽

X Ray Diffraction ◽

Melting Points ◽

Polymorphic Transitions ◽

X Ray ◽

Temperature Range ◽

Two Phases ◽

Molecular Salt

A cocrystal and a molecular salt of β-alanine and DL-tartaric acid, C3H8NO2 +·C4H4O6 −, of the same chemical composition, were studied over a wide temperature range by single-crystal and powder X-ray diffraction. Neither the interconversion between the two phases nor any polymorphic transitions were observed in the temperature range from 100 K to the melting points. This contrasts with the solvent-mediated phase transition from the salt to the cocrystal in a slurry that has been documented earlier.

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Defects in ion implanted silicon

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100109070 ◽

1978 ◽

Vol 36 (1) ◽

pp. 386-387

Author(s):

J.A. Lambert ◽

P.S. Dobson

Keyword(s):

Defect Structure ◽

Dislocation Loops ◽

Frank Loop ◽

Burgers Vector ◽

Temperature Range ◽

Perfect Dislocation ◽

Contrast Analysis ◽

Image Position ◽

Ion Implanted

The defect structure of ion-implanted silicon, which has been annealed in the temperature range 800°C-1100°C, consists of extrinsic Frank faulted loops and perfect dislocation loops, together with‘rod like’ defects elongated along <110> directions. Various structures have been suggested for the elongated defects and it was argued that an extrinsically faulted Frank loop could undergo partial shear to yield an intrinsically faulted defect having a Burgers vector of 1/6 <411>.This defect has been observed in boron implanted silicon (1015 B+ cm-2 40KeV) and a detailed contrast analysis has confirmed the proposed structure.

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Domain coarsening by grain boundary migration in ordered Ni4Mo

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100144279 ◽

1986 ◽

Vol 44 ◽

pp. 560-561

Author(s):

K. Vasudevan ◽

H. P. Kao ◽

C. R. Brooks ◽

E. E. Stansbury

Keyword(s):

Grain Boundary ◽

Grain Boundaries ◽

Short Range ◽

Boundary Migration ◽

Grain Boundary Migration ◽

Rapid Cooling ◽

Temperature Range ◽

Fee Structure ◽

Domain Coarsening ◽

Boundary Reaction

The Ni4Mo alloy has a short-range ordered fee structure (α) above 868°C, but transforms below this temperature to an ordered bet structure (β) by rearrangement of atoms on the fee lattice. The disordered α, retained by rapid cooling, can be ordered by appropriate aging below 868°C. Initially, very fine β domains in six different but crystallographically related variants form and grow in size on further aging. However, in the temperature range 600-775°C, a coarsening reaction begins at the former α grain boundaries and the alloy also coarsens by this mechanism. The purpose of this paper is to report on TEM observations showing the characteristics of this grain boundary reaction.

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The reaction of amorphous Ni-Nb films with Si in the presence of a native SiO2 layer

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100176459 ◽

1990 ◽

Vol 48 (4) ◽

pp. 664-665

Author(s):

N. Rozhanski ◽

A. Barg

Keyword(s):

High Temperature ◽

Crystallization Temperature ◽

Diffusion Barriers ◽

Sio2 Layer ◽

Si Substrate ◽

Cross Sectional ◽

Plan View ◽

Temperature Range ◽

Sputter Deposited

Amorphous Ni-Nb alloys are of potential interest as diffusion barriers for high temperature metallization for VLSI. In the present work amorphous Ni-Nb films were sputter deposited on Si(100) and their interaction with a substrate was studied in the temperature range (200-700)°C. The crystallization of films was observed on the plan-view specimens heated in-situ in Philips-400ST microscope. Cross-sectional objects were prepared to study the structure of interfaces.The crystallization temperature of Ni5 0 Ni5 0 and Ni8 0 Nb2 0 films was found to be equal to 675°C and 525°C correspondingly. The crystallization of Ni5 0 Ni5 0 films is followed by the formation of Ni6Nb7 and Ni3Nb nucleus. Ni8 0Nb2 0 films crystallise with the formation of Ni and Ni3Nb crystals. No interaction of both films with Si substrate was observed on plan-view specimens up to 700°C, that is due to the barrier action of the native SiO2 layer.

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A Transmission Electron Microscopical Investigation of Phase Transformations in TiNi

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s1431927600001446 ◽

1980 ◽

Vol 38 ◽

pp. 340-341

Author(s):

P. Moine ◽

G. M. Michal ◽

R. Sinclair

Keyword(s):

Electron Microscopy ◽

Phase Transformations ◽

Applied Stress ◽

Structural Changes ◽

Microscopical Investigation ◽

Temperature Range ◽

Transmission Electron ◽

Electron Microscopical ◽

Diffraction Effects ◽

Microscopy Images

Premartensitic effects in near equiatomic TiNi have been pointed out by several authors(1-5). These include anomalous contrast in electron microscopy images (mottling, striations, etc. ),diffraction effects(diffuse streaks, extra reflections, etc.), a resistivity peak above Ms (temperature at which a perceptible amount of martensite is formed without applied stress). However the structural changes occuring in this temperature range are not well understood. The purpose of this study is to clarify these phenomena.

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