Results 241 to 250 of about 480,384 (278)

Negative Thermal Expansion Coefficient

2019 IEEE 2nd Ukraine Conference on Electrical and Computer Engineering (UKRCON), 2019
Physical nature of negative thermal expansion coefficient ($\alpha$) in polar-sensitive dielectrics and semiconductors is explained. Physical features of inter-atomic bonds in crystals are manifested in their thermal expansion; in the polar dielectrics it is a peculiar polar-sensitive structure, arisen due to compensation of atoms electronegativity ...
Y.M. Poplavko, Y.V. Didenko, Y.I. Yakimenko   +2 more
openaire   +1 more source

Negative thermal expansion of laminates

Journal of Materials Science, 2004
Measurements have been carried out on the in-plane and through the thickness thermal expansion coefficients of glass polypropylene fibre composites of 50% volume fraction between room temperature and 120°C. Only in the temperature range 20° to 75°C are reproducible results obtained.
M. Landert, A. Kelly, R. J. Stearn, P. J. Hine   +3 more
openaire   +1 more source

Thermal Enhancement of Luminescence for Negative Thermal Expansion in Molecular Materials

Journal of the American Chemical Society, 2022
Overcoming thermal quenching is an essential issue in the practical application of luminescent materials. Herein, we found that negative thermal expansion (NTE) can achieve the thermal enhancement of luminescence in molecular materials based on three metal-organic frameworks CuX-bpy (X = Cl, Br, I; bpy = 4,4'-bipyridine).
Liang Chen, Xin Chen, Rui Ma, Kun Lin, Qiang Li, Jian-Ping Lang, Chunyu Liu, Kenichi Kato, Ling Huang, Xianran Xing   +9 more
openaire   +2 more sources

Negative Thermal Expansion

2020
This chapter reviews the various 2D NTE systems, including those constructed from bimaterial strips, laminates (of various stiffness disparity), trusses (of triangular cells, Y-shaped elements, and Hoberman circle), meshes, rigid unit modes, and ring-rod assemblies (both 2D and 3D). Finally, a few examples of 3D NTE structures are briefly mentioned.
openaire   +1 more source

Local behaviour of negative thermal expansion materials

Nuclear Instruments and Methods in Physics Research Section B: Beam Interactions with Materials and Atoms, 2006
EXAFS can represent a powerful probe of the local behaviour of negative thermal expansion (NTE) materials, thanks to the possibility of measuring the expansion of selected inter-atomic bonds and the perpendicular relative atomic displacements. The effectiveness of EXAFS for NTE studies is illustrated by a comparison of results recently obtained on ...
Fornasini, Paolo, Dalba, Giuseppe, Grisenti, Rolly, Purans, Juris, Vaccari, Marco, F. Rocca, Sanson, Andrea   +6 more
openaire   +6 more sources

On the Origin of the Negative Thermal Expansion Behavior of YCu

Inorganic Chemistry, 2019
Among the intermetallics and alloys, YCu is an unusual material because it displays negative thermal expansion without spin ordering. The mechanism behind this behavior that is caused by the structural phase transition of YCu has yet to be fully understood. To gain insight into this mechanism, we experimentally examined the crystal structure of the low-
Hiroshi Mizoguchi, Joonho Bang, Takeshi Inoshita, Toshio Kamiya, Hideo Hosono   +4 more
openaire   +2 more sources

ISOTROPIC NEGATIVE THERMAL EXPANSION

Annual Review of Materials Science, 1998
▪ Abstract  Materials that contract on heating are unusual and have important applications. Materials showing such negative thermal expansion behavior are usually anisotropic and usually exhibit this behavior over only a small temperature range.
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Origin of negative thermal expansion phenomenon in solids

Scripta Materialia, 2011
We show that the negative thermal expansion (NTE) phenomenon originates from the existence of high pressure, small volume phases with higher entropy, with their configurations present in the stable phase matrix through thermal fluctuations, thus exists.
Zi-Kui Liu, Yi Wang, Shun-Li Shang
openaire   +1 more source

Reversible negative thermal expansion of polymer films

Physical Review E, 2002
A basic understanding of the properties of thin polymer films is of fundamental importance for developing applications in nanotechnology. Results of energy and angle dispersive x-ray reflectivity measurements on polymer thin films as a function of temperature exhibit reversible negative thermal expansion below the glass transition temperature T(g ...
M, Mukherjee, M, Bhattacharya, M K, Sanyal, Th, Geue, J, Grenzer, U, Pietsch   +5 more
openaire   +2 more sources

Coprecipitation synthesis and negative thermal expansion of NbVO5

Dalton Transactions, 2011
We develop a coprecipitation synthesis route to prepare NbVO(5) with simple oxide Nb(2)O(5) and NH(4)VO(3) as starting materials. No metal alkoxide or organometallic substance was used in the process. Nano-crystal NbVO(5) was obtained by calcination of the coprecipitates at 550 °C for 2 h. DSC/TG and XRD investigations indicate that the target compound
Wang, Jinrui, Deng, Jinxia, Yu, Ranbo, Chen, Jun, Xing, Xianran   +4 more
openaire   +3 more sources