X-ray measure of tensile force in post-tensioned steel cables

Objectives: We previously reported excellent findings of X-ray phase-contrast tomography (PCX) for visualization of the formalin-fixed human aortic wall samples, and PCX enabled to demonstrate changes of tunica media in acute type A aortic dissection (AADA) . This study evaluates quantitative and dynamic measurements of fresh aortic wall samples of AADA with this modality. Methods: Fresh human aortic samples of the ascending aorta (n=7) were obtained during emergent aortic repair for AADA. Formalin-fixed human aortic walls of AADA (n=15) and normal aorta (n=15) were also investigated. PCX is approximately 1000 times more sensitive than absorption-contrast X-ray imaging and effective resolution of PCX is 11.7 μm. Quantitative and dynamic measurement has been developed to visualize changes in imaging of fresh aortic wall under various tensile force to simulate physiological condition, in which aortic wall is stretched according to blood pressure. Results: In normal aorta, quantitative measurement of density of the media was 1.095±0.003(g/cm3), and no different between intimal side (1.083±0.002) and adventitial side (1.085±0.003). On contrast, in formalin-fixed aorta of AADA, the medial density was 1.063±0.027, significantly lower than normal aorta (Figure-1), and different between intimal side and adventitial side (1.061±0.008 vs 1.081±0.011, respectively; p<0.005). In fresh sample of AADA, distribution of the medial density was equal to that of formalin-fixed aorta and differences of the medial density were clearly observed with elevation of tensile force of the aortic wall (Figure-1). These differences in density within tunica media were well correlated with distribution of elastic fibers and existence of cystic medial necrosis in pathological analysis. Conclusions: X-ray phase-contrast tomography was a strong modality to understand aortic structures and pathogenesis of acute type A aortic dissection.

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The Thermal Behavior of γ-PA1010: Evolution of Structure and Morphology in the Simultaneous Thermal Stretched Films

Materials ◽

10.3390/ma13071722 ◽

2020 ◽

Vol 13 (7) ◽

pp. 1722 ◽

Cited By ~ 1

Author(s):

Zhenya Zhang ◽

Wentao Liu ◽

Hao Liu ◽

Aihua Sun ◽

Yeonwoo Yoo ◽

...

Keyword(s):

Draw Ratio ◽

Room Temperature ◽

Tensile Force ◽

X Ray ◽

Maximum Value ◽

Degree Of Orientation ◽

Higher Temperature ◽

Evolution Of Structure ◽

The Difference ◽

Polyamide 1010

In this work, polyamide 1010 (PA1010) films were prepared by melt-quenching. A wide-angle X-ray diffractometer (WAXD) with a thermal stretching stage was used to investigate the structure transformation, crystallinity and degree of orientation in the course of simultaneous thermally stretched PA1010. The crystallinity increased along with the increase of draw ratio and then decreased as the draw ratio was over 2.00 times—which the maximum value reached when the draw ratio was about 2.00 times. The degree of orientation of γ-PA1010 was much greater at higher temperature than room temperature (RT); the difference gradually became weaker with the increase of draw ratio. There was a linear relationship between the draw ratios and tensile force at higher temperatures, and the tensile force increased with the increase of draw ratios. The tensile force may induce crystallization and promote orientation in the course of simultaneous thermally stretched PA1010. These phenomena are beneficial to understand the structure-processing-performance relationship and provide some theoretical basis for the processing and production.

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EXPERIMENT ON SHEAR OF POST-TENSIONED CONNECTION BETWEEN CONCRETE AND CAST IRON PLATE HAVING SHEAR-KEY

Proceedings of International Structural Engineering and Construction ◽

10.14455/isec.res.2015.167 ◽

2015 ◽

Vol 2 (1) ◽

Author(s):

Kiyoka Kinoshita ◽

Yusuke Maida ◽

Hiroyasu Sakata ◽

Kazushi Shimazaki ◽

Eiichiro Saeki ◽

...

Keyword(s):

Cast Iron ◽

Tensile Force ◽

Frictional Resistance ◽

Rc Beam ◽

Iron Plate ◽

Friction Resistance ◽

Shear Key ◽

Post Tensioned

In this paper, post-tensioned connection between concrete and cast iron plate having shear-key was adopted. Frictional resistance acts when there is no displacement between concrete and cast iron plate, shear-key also act to transmit stress to RC beam at the same time as the frictional resistance when the displacement occurs. Each specimen consists of RC beam and plate simulating post-tensioned connection. Ten specimens were tested. The parameter are type of plate, with or without the shear-key, the height of the shear-key, amount of the shear-key, difference between the post-tensioned force and whether or not applying vertical tensile force. In conclusion, it was needless to think their displacement by post-tensioned connection. And the strength of specimens with shear-key is presented by the sum of friction resistance and bearing resistance by using anamnestic formula.

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Space and Time Distribution of Hard X-Ray Emission in a Loop at the Beginning of a Flare

International Astronomical Union Colloquium ◽

10.1017/s0252921100025446 ◽

1994 ◽

Vol 144 ◽

pp. 275-277

Author(s):

M. Karlický ◽

J. C. Hénoux

Keyword(s):

Time Distribution ◽

Electron Bombardment ◽

Spatial Evolution ◽

Superthermal Electrons ◽

Flare Loop ◽

X Ray ◽

Superthermal Electron ◽

Flare Loops ◽

Chromospheric Evaporation ◽

Temporal And Spatial

AbstractUsing a new ID hybrid model of the electron bombardment in flare loops, we study not only the evolution of densities, plasma velocities and temperatures in the loop, but also the temporal and spatial evolution of hard X-ray emission. In the present paper a continuous bombardment by electrons isotropically accelerated at the top of flare loop with a power-law injection distribution function is considered. The computations include the effects of the return-current that reduces significantly the depth of the chromospheric layer which is evaporated. The present modelling is made with superthermal electron parameters corresponding to the classical resistivity regime for an input energy flux of superthermal electrons of 109erg cm−2s−1. It was found that due to the electron bombardment the two chromospheric evaporation waves are generated at both feet of the loop and they propagate up to the top, where they collide and cause temporary density and hard X-ray enhancements.

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Some Problems in Understanding the Solar Corona

International Astronomical Union Colloquium ◽

10.1017/s025292110002491x ◽

1994 ◽

Vol 144 ◽

pp. 1-9

Author(s):

A. H. Gabriel

Keyword(s):

Solar Corona ◽

Solar Atmosphere ◽

Theoretical Modelling ◽

Total System ◽

Major Advance ◽

X Ray ◽

Proper Perspective ◽

Space Observations

The development of the physics of the solar atmosphere during the last 50 years has been greatly influenced by the increasing capability of observations made from space. Access to images and spectra of the hotter plasma in the UV, XUV and X-ray regions provided a major advance over the few coronal forbidden lines seen in the visible and enabled the cooler chromospheric and photospheric plasma to be seen in its proper perspective, as part of a total system. In this way space observations have stimulated new and important advances, not only in space but also in ground-based observations and theoretical modelling, so that today we find a well-balanced harmony between the three techniques.

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White-Light Coronal Structures: Streamers and CMEs

International Astronomical Union Colloquium ◽

10.1017/s0252921100025045 ◽

1994 ◽

Vol 144 ◽

pp. 82

Author(s):

E. Hildner

Keyword(s):

Emission Line ◽

Electron Density ◽

White Light ◽

Coronal Mass Ejections ◽

X Rays ◽

Solar Cycles ◽

Temperature Function ◽

X Ray ◽

Eclipse Observations ◽

Coronal Structures

AbstractOver the last twenty years, orbiting coronagraphs have vastly increased the amount of observational material for the whitelight corona. Spanning almost two solar cycles, and augmented by ground-based K-coronameter, emission-line, and eclipse observations, these data allow us to assess,inter alia: the typical and atypical behavior of the corona; how the corona evolves on time scales from minutes to a decade; and (in some respects) the relation between photospheric, coronal, and interplanetary features. This talk will review recent results on these three topics. A remark or two will attempt to relate the whitelight corona between 1.5 and 6 R⊙to the corona seen at lower altitudes in soft X-rays (e.g., with Yohkoh). The whitelight emission depends only on integrated electron density independent of temperature, whereas the soft X-ray emission depends upon the integral of electron density squared times a temperature function. The properties of coronal mass ejections (CMEs) will be reviewed briefly and their relationships to other solar and interplanetary phenomena will be noted.

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Iron K-Line Emission from X-Ray Binaries

International Astronomical Union Colloquium ◽

10.1017/s0252921100107389 ◽

1988 ◽

Vol 102 ◽

pp. 47-50

Author(s):

K. Masai ◽

S. Hayakawa ◽

F. Nagase

Keyword(s):

Accretion Disk ◽

Radiative Recombination ◽

Characteristic Temperature ◽

Line Emission ◽

Ionization Front ◽

Continuum Radiation ◽

X Ray ◽

Low Mass ◽

X Ray Binaries

AbstractEmission mechanisms of the iron Kα-lines in X-ray binaries are discussed in relation with the characteristic temperature Txof continuum radiation thereof. The 6.7 keV line is ascribed to radiative recombination followed by cascades in a corona of ∼ 100 eV formed above the accretion disk. This mechanism is attained for Tx≲ 10 keV as observed for low mass X-ray binaries. The 6.4 keV line observed for binary X-ray pulsars with Tx> 10 keV is likely due to fluorescence outside the He II ionization front.

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Diagnostics of Gold Laser Plasmas

International Astronomical Union Colloquium ◽

10.1017/s0252921100108085 ◽

1988 ◽

Vol 102 ◽

pp. 357-360

Author(s):

J.C. Gauthier ◽

J.P. Geindre ◽

P. Monier ◽

C. Chenais-Popovics ◽

N. Tragin ◽

...

Keyword(s):

Experimental Results ◽

Pure Gold ◽

Electronic Temperature ◽

X Ray ◽

Laser Plasmas ◽

Collisional Radiative Model ◽

Radiative Model

AbstractIn order to achieve a nickel-like X ray laser scheme we need a tool to determine the parameters which characterise the high-Z plasma. The aim of this work is to study gold laser plasmas and to compare experimental results to a collisional-radiative model which describes nickel-like ions. The electronic temperature and density are measured by the emission of an aluminium tracer. They are compared to the predictions of the nickel-like model for pure gold. The results show that the density and temperature can be estimated in a pure gold plasma.

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Axial Observation of X-Ray Spectra from a Beam-Foil Source

International Astronomical Union Colloquium ◽

10.1017/s0252921100108048 ◽

1988 ◽

Vol 102 ◽

pp. 339-342

Author(s):

J.M. Laming ◽

J.D. Silver ◽

R. Barnsley ◽

J. Dunn ◽

K.D. Evans ◽

...

Keyword(s):

Spectral Resolution ◽

Heavy Ion ◽

Ion Beams ◽

Beam Axis ◽

Doppler Broadening ◽

X Ray ◽

Beam Foil

AbstractNew observations of x-ray spectra from foil-excited heavy ion beams are reported. By observing the target in a direction along the beam axis, an improvement in spectral resolution, δλ/λ, by about a factor of two is achieved, due to the reduced Doppler broadening in this geometry.

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