High-resolution measurements of thermal expansion along the uniqueb-axis of squaric acid

1984 ◽  
Vol 56 (1) ◽  
pp. 41-49 ◽  
Author(s):  
T. H. Johansen ◽  
J. Feder ◽  
T. J�ssang
Keyword(s):  
Thermal Expansion ◽  
High Resolution ◽  
Squaric Acid

Novel Silicon-Elastomers for Advanced Soft Lithography

2006 ◽  
Vol 947 ◽  
Author(s):  
Kyung Choi
Keyword(s):  
Thermal Expansion ◽  
High Resolution ◽  
Soft Lithography ◽  
Materials Properties ◽  
Nano Scale ◽  
Thermal Expansion Coefficients ◽  
High Thermal Expansion ◽  
Expansion Coefficients

ABSTRACTHigh resolution pattern transfers in the nano-scale regime have been considerable challenges in ‘soft lithography’ to achieve nanodevices with enhanced performances. In this technology, the resolution of pattern integrations is significantly rely on the materials' properties of polydimethylsiloxane (PDMS) stamps. Since commercial PDMS stamps have shown limitations in nano-scale resolution soft lithography due to their low physical toughness and high thermal expansion coefficients, we developed stiffer, photocured PDMS silicon elastomers designed, specifically for nano-sized soft lithography and photopatternable nanofabrications.

scholarly journals Synchrotron high-resolution XRD and thermal expansion of synthetic Mg calcites

2020 ◽  
Vol 47 (11) ◽  
Author(s):  
Nicole Floquet ◽  
Daniel Vielzeuf ◽  
Vasile Heresanu ◽  
Didier Laporte ◽  
Jonathan Perrin
Keyword(s):  
Thermal Expansion ◽  
High Resolution

scholarly journals An examination of the thermal expansion of urea using high-resolution variable-temperature X-ray powder diffraction

2005 ◽  
Vol 38 (6) ◽  
pp. 1038-1039 ◽  
Author(s):  
Robert Hammond ◽  
Klimentina Pencheva ◽  
Kevin J. Roberts ◽  
Patricia Mougin ◽  
Derek Wilkinson
Keyword(s):  
Thermal Expansion ◽  
High Resolution ◽  
Variable Temperature ◽  
X Ray Diffraction ◽  
Polymorphic Transformations ◽  
X Ray ◽  
Thermal Expansion Coefficients ◽  
Cell Dimensions ◽  
Expansion Coefficients ◽  
Unit Cell Dimensions

Variable-temperature high-resolution capillary-mode powder X-ray diffraction is used to assess changes in unit-cell dimensions as a function of temperature over the range 188–328 K. No evidence was found for any polymorphic transformations over this temperature range and thermal expansion coefficients for urea were found to be αa= (5.27 ± 0.26) × 10−5 K−1and αc= (1.14 ± 0.057) × 10−5 K−1.

scholarly journals Setup of high resolution thermal expansion measurements in closed cycle cryostats using capacitive dilatometers

2021 ◽  
Author(s):  
Neeraj Kumar Rajak ◽  
Neha Kondedan ◽  
Husna Jan ◽  
Muhammed Dilshah U ◽  
Navya S. D. ◽  
...  
Keyword(s):  
Thermal Expansion ◽  
High Resolution ◽  
High Temperature Superconductors ◽  
Linear Thermal Expansion ◽  
Measurement Data ◽  
Relative Sensitivity ◽  
Published Data ◽  
Closed Cycle ◽  
Noise Mitigation ◽  
Thermal Expansion Data

Abstract We present high resolution thermal expansion measurement data obtained with high relative sensitivity of ΔL/L = 10-9 and accuracy of ±2% using closed cycle refrigerators employing two different dilatometers. Experimental details of the set-up utilizing the multi-function probe integrated with the cold head of two kinds of closed cycle refrigerators, namely, pulse tube and Gifford-McMahon cryocoolers, has been described in detail. The design consists of decoupling the bottom sample puck and taking connections from the top of the multi-function probe to mitigate the vibrational noise arising from the cold heads, using which smooth and high quality thermal expansion data could be obtained. It was found that dilatometer #2 performs a better noise mitigation than dilatometer #1 due to the constrained movement of the spring in dilatometer #2. This was confirmed by finite element method simulations that were performed for understanding the spring movement in each dilatometer using which the effect of different forces/pressures and vibrations on the displacement of the spring was studied. Linear thermal expansion coefficient α obtained using both dilatometers was evaluated using derivative of a polynomial fit. The resultant α obtained using dilatometer #2 and either of the closed cycle cryostats on standard metals silver and aluminium showed excellent match with published values obtained using wet cryostats. Finally, thermal expansion measurements is reported on single crystals of two high temperature superconductors YBa2Cu3-xAlxO6+δ and Bi2Sr2CaCu2O8+x along the c-axis with very good match found with published data obtained earlier using wet liquid helium based cryostats.

Thermal expansion of single-crystalline β-Ga2O3 from RT to 1200 K studied by synchrotron-based high resolution x-ray diffraction

2018 ◽  
Vol 113 (18) ◽  
pp. 182102 ◽  
Author(s):  
Zongzhe Cheng ◽  
Michael Hanke ◽  
Zbigniew Galazka ◽  
Achim Trampert
Keyword(s):  
Thermal Expansion ◽  
High Resolution ◽  
X Ray Diffraction ◽  
Single Crystalline ◽  
X Ray

High-resolution measurements of the thermal expansion of superconducting Co-dopedBaFe2As2

2009 ◽  
Vol 79 (21) ◽  
Author(s):  
M. S. da Luz ◽  
J. J. Neumeier ◽  
R. K. Bollinger ◽  
A. S. Sefat ◽  
M. A. McGuire ◽  
...  
Keyword(s):  
Thermal Expansion ◽  
High Resolution

High-resolution thermal expansion of superconducting fulleridesA3C60(A=K,Rb)

1996 ◽  
Vol 54 (10) ◽  
pp. R6865-R6868 ◽  
Author(s):  
G. J. Burkhart ◽  
C. Meingast
Keyword(s):  
Thermal Expansion ◽  
High Resolution

scholarly journals Thermal expansion and atomic displacement parameters of cubic KMgF3perovskite determined by high-resolution neutron powder diffraction

2002 ◽  
Vol 35 (3) ◽  
pp. 291-295 ◽  
Author(s):  
I. G. Wood ◽  
K. S. Knight ◽  
G. D. Price ◽  
J. A. Stuart
Keyword(s):  
Thermal Expansion ◽  
High Resolution ◽  
Powder Diffraction ◽  
Room Temperature ◽  
Coefficient Of Thermal Expansion ◽  
Atomic Displacement ◽  
Debye Model ◽  
Neutron Powder Diffraction ◽  
First Derivative ◽  
Atomic Displacement Parameters

The structure of KMgF3has been determined by high-resolution neutron powder diffraction at 4.2 K, room temperature and at 10 K intervals from 373 K to 1223 K. The material remains cubic at all temperatures. The average volumetric coefficient of thermal expansion in the range 373–1223 K was found to be 7.11 (3) × 10−5 K−1. For temperatures between 4.2 and 1223 K, a second-order Grüneisen approximation to the zero-pressure equation of state, with the internal energy calculatedviaa Debye model, was found to fit well, with the following parameters: θD= 536 (9) K,Vo= 62.876 (6) Å3, K_{o}^{\,\prime} = 6.5 (1) and (VoKo/γ′) = 3.40 (2) × 10−18 J, where θDis the Debye temperature,Vois the volume atT= 0, K_{o}^{\,\prime} is the first derivative with respect to pressure of the incompressibility (Ko) and γ′ is a Grüneisen parameter. The atomic displacement parameters were found to increase smoothly withTand could be fitted using Debye models with θDin the range 305–581 K. At 1223 K, the displacement of the F ions was found to be much less anisotropic than that in NaMgF3at this temperature.

ANISOTROPIC THERMAL EXPANSION IN DIBORIDES AS A FUNCTION OF MICRO-STRAIN

2003 ◽  
Vol 17 (04n06) ◽  
pp. 812-818 ◽  
Author(s):  
S. AGRESTINI ◽  
D. DI CASTRO ◽  
M. SANSONE ◽  
N. L. SAINI ◽  
A. BIANCONI ◽  
...  
Keyword(s):  
Thermal Expansion ◽  
High Resolution ◽  
Powder Diffraction ◽  
Atomic Radius ◽  
The State ◽  
X Ray ◽  
Anisotropic Thermal Expansion ◽  
Thermal Expansion Anisotropy

Thermal expansion of diborides ( AB 2), with different intercalated atoms (A) is studied as a function of temperature in the range of 100-370 K by high-resolution x-ray powder diffraction. The results indicate a well defined relationship between the anisotropy of the thermal expansion and the micro-strain of the boron layers, ε a = (a-a0)/a0 (where a0 = c/1.08 is the equilibrium a-axis for an unstrained AB2 system), determined by the atomic radius of the intercalated atoms. The thermal expansion is isotropic at εa = 0 (i.e., near c/a = 1.08) while the AB 2 system is unstrained, and it gets anisotropic away from the equilibrium. The anisotropy increases with increasing micro-strain in both directions (positive or negative, i.e. tensile or compressive) suggesting that the micro-strain is a key variable to define the state of diborides. As a matter of fact, the MgB 2 with the highest T c shows a tensile micro-strain, εa = 6% and a large thermal expansion anisotropy.

Sign in / Sign up

Export Citation Format

Share Document