In Situ X-Ray Diffraction Measurements of the Apparent Modulus of Human Dental Tissue in the Vicinity of the Dentine-Enamel Junction (DEJ)

The dentine-enamel junction (DEJ) is an important biological interface between the highly mineralized hard out layer (enamel) and the comparatively softer tooth core (dentine) of teeth. The remarkable performance of this interface provides the motivation for investigation into the detailed structure and function of the DEJ. In this study, synchrotron X-ray diffraction measurements of the DEJ subjected to the in situ uniaxial loading were carried out to capture the structure-property relationship between the DEJ architecture and its response to the applied force. The knowledge of the architecture and properties of the natural DEJ will hopefully help in biomimetic engineering of superior dental restorations and prostheses, and the development of novel materials to emulate the DEJ.

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Evolution of Carbon Fiber Microstructure During Carbonization and High-Temperature Graphitization Measured In Situ Using Synchrotron Wide-Angle X-ray Diffraction

MRS Proceedings ◽

10.1557/opl.2015.636 ◽

2015 ◽

Vol 1754 ◽

pp. 13-18 ◽

Cited By ~ 1

Author(s):

Michael Behr ◽

James Rix ◽

Brian Landes ◽

Bryan Barton ◽

Eric Hukkanen ◽

...

Keyword(s):

High Temperature ◽

Carbon Fiber ◽

Tensile Modulus ◽

Fiber Bundles ◽

Wide Angle ◽

High Modulus ◽

Structure Property ◽

X Ray Diffraction ◽

X Ray

ABSTRACTThis paper will discuss the structure-property model developed that correlates the tensile modulus to the elastic properties and angular distribution of constituent graphitic layers for carbon fiber derived from a polyethylene precursor. In addition, a high-temperature fiber tensile device was built to enable heating of carbon fiber bundles at a variable rate from 25 °C to greater than ∼2300 °C, while simultaneously applying a tensile stress. This capability combined with synchrotron wide-angle x-ray diffraction (WAXD), enabled observation in situ and in real time of the microstructural transformation from different carbon fiber precursors to high-modulus carbon fiber. Experiments conducted using PAN- and PE-derived fiber precursors reveal stark differences in their carbonization and high-temperature graphitization behavior.

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Structure–Property Relationship in Melt-Spun Poly(hydroxybutyrate-co-3-hexanoate) Monofilaments

Polymers ◽

10.3390/polym14010200 ◽

2022 ◽

Vol 14 (1) ◽

pp. 200

Author(s):

Figen Selli ◽

Rudolf Hufenus ◽

Ali Gooneie ◽

Umit Halis Erdoğan ◽

Edith Perret

Keyword(s):

Melt Spinning ◽

Structure Property ◽

X Ray Diffraction ◽

X Ray ◽

X Ray Scattering ◽

Tensile Performance ◽

Structure Property Relationship ◽

Melt Spun ◽

Structural Differences ◽

Ice Water

Poly(hydroxybutyrate-co-3-hexanoate) (PHBH) is a biodegradable thermoplastic polyester with the potential to be used in textile and medical applications. We have aimed at developing an upscalable melt-spinning method to produce fine biodegradable PHBH filaments without the use of an ice water bath or offline drawing techniques. We have evaluated the effect of different polymer grades (mol% 3-hydroxy hexanoate, molecular weight etc.) and production parameters on the tensile properties of melt-spun filaments. PHBH monofilaments (diameter < 130 µm) have been successfully melt-spun and online drawn from three different polymer grades. We report thermal and rheological properties of the polymer grades as well as morphological, thermal, mechanical, and structural properties of the melt-spun filaments thereof. Tensile strengths up to 291 MPa have been achieved. Differences in tensile performance have been correlated to structural differences with wide-angle X-ray diffraction and small-angle X-ray scattering. The measurements obtained have revealed that a synergetic interaction of a highly oriented non-crystalline mesophase with highly oriented α-crystals leads to increased tensile strength. Additionally, the effect of aging on the structure and tensile performance has been investigated.

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High-speed X-ray diffraction and in situ resistivity measurements at temperatures of 100 to 1000 K

Journal of Applied Crystallography ◽

10.1107/s0021889889006412 ◽

1989 ◽

Vol 22 (6) ◽

pp. 523-527 ◽

Cited By ~ 2

Author(s):

J. Angilello ◽

R. D. Thompson ◽

K. N. Tu

Keyword(s):

High Speed ◽

Angular Resolution ◽

Gold Film ◽

Structure Property ◽

X Ray Diffraction ◽

Ray Method ◽

X Ray ◽

Resistivity Measurements ◽

Beam Focusing

A system has been constructed which uses a primary-beam focusing monochromator Debye–Scherrer X-ray method to perform simultaneously in situ X-ray diffraction and resistivity measurements at temperatures of 100 to 1000 K. The Inel curved linear detector, which is capable of recording 120° of 20 angle without moving the detector, makes the Debye–Scherrer geometry possible for high-speed dynamic studies. The angular resolution of this system is sufficient to observe the separation of a mixture of tungsten and molybdenum powders. The sensitivity of the system makes it possible to record the diffraction pattern from a 100 Å gold film. The sheet resistivity of the sample can be recorded simultaneously to provide a structure-property correlation. Comparisons with other X-ray diffraction methods using thin films are discussed.

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The Use of Advanced Analytical Techniques for Characterization of the Chemical, Physical, and Crystallographic Nature of a Surface

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100071107 ◽

1973 ◽

Vol 31 ◽

pp. 132-133 ◽

Cited By ~ 1

Author(s):

R. E. Herfert

Keyword(s):

Surface Characterization ◽

Analytical Techniques ◽

X Ray Diffraction ◽

Depth Of Penetration ◽

X Ray ◽

The Past ◽

Transmission Electron ◽

Scanning Electron

Studies of the nature of a surface, either metallic or nonmetallic, in the past, have been limited to the instrumentation available for these measurements. In the past, optical microscopy, replica transmission electron microscopy, electron or X-ray diffraction and optical or X-ray spectroscopy have provided the means of surface characterization. Actually, some of these techniques are not purely surface; the depth of penetration may be a few thousands of an inch. Within the last five years, instrumentation has been made available which now makes it practical for use to study the outer few 100A of layers and characterize it completely from a chemical, physical, and crystallographic standpoint. The scanning electron microscope (SEM) provides a means of viewing the surface of a material in situ to magnifications as high as 250,000X.

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