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

Materials ◽  
2020 ◽  
Vol 13 (7) ◽  
pp. 1722 ◽  
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.

5d and 4f electron configuration of CeB6 at 340 and 535 K

2008 ◽  
Vol 64 (5) ◽  
pp. 534-549 ◽  
Author(s):  
Ryoko Makita ◽  
Kiyoaki Tanaka ◽  
Yoshichika Ōnuki
Keyword(s):  
Electron Transfer ◽  
Crystal Field ◽  
Ground State ◽  
Room Temperature ◽  
Atomic Orbital ◽  
Energy Levels ◽  
Electron Configuration ◽  
Acta Cryst ◽  
X Ray ◽  
The Difference

X-ray atomic orbital (XAO) analysis revealed that at both temperatures the electrons are transferred from B 2px (= py ) to Ce 5d and 4f orbitals. At 340 K 5d(j = 5/2)Γ8 orbitals are occupied partially, but 4f(j = 5/2)Γ8 orbitals are more populated than 4f(j = 5/2)Γ7 orbitals, in contrast to our observation at 430 K [Makita et al. (2007). Acta Cryst. B63, 683–692]. At 535 K the XAO analysis revealed clearly that the order of the energy levels of 4f(j = 5/2)Γ8 and Γ7 states reversed again and is the same as that at room temperature. It also limited the possible 5d configurations to three models among the nine possible ones. However, the XAO analysis could not decide which of the three models was the best with the present accuracy of the measurement. Two of them have partially and fully occupied 5d(j = 5/2)Γ7 orbitals and the remaining one has a fully occupied 5d(j = 3/2)Γ8 orbital. Since the lobes of 5d(j = 3/2)Γ8 or 5d(j = 5/2)Γ7 orbitals do not overlap with the 4f(j = 5/2)Γ8 orbitals as well as the 5d(j = 5/2)Γ8 orbitals, the order of the energy levels of the 4f(j = 5/2) orbitals became the same as that at room temperature. These results indicate that the crystal field varies with temperature due to the electron transfer from B 2p to Ce 5d orbitals. The difference densities after the spherical-atom refinement at the three temperatures clearly revealed the different combinations of 4f and 5d orbitals which are occupied. In the present study positive peaks due to the 4f electrons appear near the Ce nucleus and those due to 5d orbitals are found in the area outside the 4f peaks. Between the two areas there is a negative area distributed spherically at 340 K. The negative area produced by the contraction of 4f(j = 5/2)Γ8 orbitals seems to reduce the electron repulsion of the 5d(j = 5/2)Γ8 orbitals and helps the 4f(j = 5/2)Γ8 orbitals to remain as the ground state.

Effect of Deposition Temperature on the Structure and Mechanical Properties of Ti-6Al-4V Film

2013 ◽  
Vol 749 ◽  
pp. 643-647 ◽  
Author(s):  
Lei Li ◽  
Ya Feng Lu ◽  
Wen Xue Li ◽  
Li Ying Zeng ◽  
Yi Yang ◽  
...  
Keyword(s):  
Mechanical Properties ◽  
Room Temperature ◽  
Elastic Moduli ◽  
Preferred Orientation ◽  
Nanoindentation Test ◽  
X Ray Diffraction ◽  
X Ray ◽  
Phase Direction ◽  
Higher Temperature ◽  
Substrate Temperatures

Ti-6Al-4V films were deposited by direct-current magnetron sputtering at different substrate temperatures. The structure and the surface morphology of the films were characterized by X-ray diffraction (XRD) and scanning electron microscopy (SEM). The hardness and elastic moduli of Ti-6Al-4V films were measured by nanoindentation test. The results showed that the phase direction of the films deposited at room temperature was (102) orientation, and turned to almost complete (002) preferred orientation at 300°C. For a higher temperature of 500°C, the preferred orientation of the film disappeared and presented a random grain orientation. The hardness and elastic moduli of Ti-6Al-4V films obviously showed the dependence on the temperature. The relationships among temperature, microstructure and mechanical properties of Ti-6Al-4V films were discussed in this paper.

Granular Structure and Magnetic Properties of FePt/C Films

2005 ◽  
Vol 475-479 ◽  
pp. 3729-3732
Author(s):  
Cong Mian Zhen ◽  
Xiao Xia Zhai ◽  
Chengfu Pan ◽  
Xiangfu Nie
Keyword(s):  
Room Temperature ◽  
Magnetic Measurements ◽  
Carbon Layer ◽  
Fept Nanoparticles ◽  
X Ray Diffraction ◽  
X Ray ◽  
L10 Structure ◽  
Probe Microscope ◽  
Higher Temperature ◽  
20 Nm

FePt/C mutilayer films were successfully prepared by using RF and DC magnetron sputtering system. FePt nanoparticles embedded in a C matrix were formed by consequently annealing. X-ray diffraction (XRD) results show the degree of atomic ordering of the L10 structure increases with higher temperature annealing. Room temperature magnetic measurements reveal that in-plane coercivity HC, and squareness Mr/MS depend on the thickness of carbon layer. Relatively High HC (3245.1Oe) and squareness (0.67) were obtained when the thickness of C layer is 2.0 nm. The carbon layer not only isolates the FePt grain, but also suppresses the growth of fct FePt grains. When the thickness of carbon layer is 2.0 nm, the FePt grain size decreases down to ~20 nm measured by Scan Probe Microscope (SPM). Interactions between particles can be tuned to near zero when we select the proper thickness of C layer.

Beiträge zum thermischen Verhalten von Sulfaten, IV* Neues zum Verhalten von PbSO4 bei höherer Temperatur / Contributions to the Thermal Behaviour of Sulfates, IV* New Facts About the Behaviour of PbSO4 at Higher Temperature

1979 ◽  
Vol 34 (3) ◽  
pp. 431-433 ◽  
Author(s):  
Manfred Spieß ◽  
Reginald Gruehn
Keyword(s):  
High Temperature ◽  
Crystal Structures ◽  
Thermal Behaviour ◽  
Room Temperature ◽  
X Ray ◽  
Temperature Form ◽  
Higher Temperature ◽  
Thermal Dilatation ◽  
High Temperature Form

Abstract Thermal Behaviour, Crystal Structures, Modifications Using the high temperature Guinier technique the transformation of the room temperature form N-PbSO4 to the cubic high-temperature form H-PbSO4 was observed. The nonquenchable H-PbSO4 modification crystallizes in the α-NaClO4-type with a(900°) = 7,23 Å, Z = 4 and dX-ray (900 °C) = 5,33 g/cm3 . The thermal dilatation of N-and H-PbSO4 was measured.

Two- and Three-Beam X-ray Diffraction Imaging of Domains in Magnetite

1998 ◽  
Vol 31 (5) ◽  
pp. 726-732
Author(s):  
C. Medrano ◽  
F. Heyroth ◽  
M. Schlenker ◽  
J. Baruchel ◽  
J. Espeso
Keyword(s):  
Synchrotron Radiation ◽  
Room Temperature ◽  
X Ray Diffraction ◽  
Large Crystal ◽  
Angular Sensitivity ◽  
X Ray ◽  
Diffraction Imaging ◽  
The Difference ◽  
Topographic Imaging ◽  
Radiation Beams

The X-ray diffraction topographic imaging process for ferrimagnetic domains in magnetite Fe3O4at room temperature is investigated, in two- and three-beam cases, for incident synchrotron radiation beams differing in angular divergence and energy spread. In the usual two-beam configuration, domain or wall contrast is obtained from the difference in Bragg conditions, or from the slight difference in the direction of the beams diffracted by neighbouring domains, revealed by the large crystal-to-film distance that can be used at a third-generation synchrotron radiation facility. A three-beamUmweganregungcase involving the weak 171 and the strong 131 reflections shows unusual domain contrast on the 171 topographs, even on images involving energy or angle integration; this contrast is particularly evident on white-beam topographs. The high angular sensitivity this implies is associated with the difference in dispersion relation between the two reflections.

A METHANOL–WATER COMPLEX STABILIZED ON A Zn(0001) SURFACE

2003 ◽  
Vol 10 (01) ◽  
pp. 87-94 ◽  
Author(s):  
S. VIJAYALAKSHMI ◽  
C. P. VINOD ◽  
G. U. KULKARNI
Keyword(s):  
Photoelectron Spectroscopy ◽  
Room Temperature ◽  
Bond Cleavage ◽  
Liquid Mixtures ◽  
Proton Abstraction ◽  
X Ray ◽  
Water Complex ◽  
Higher Temperature ◽  
Pure Methanol ◽  
Rich Mixtures

Coadsorption of water and methanol on a clean Zn(0001) surface has been investigated by employing X-ray photoelectron spectroscopy after exposing the surface at 80 K to the binary vapor from water–methanol liquid mixtures of varying compositions and subsequently warming the surface up to the room temperature. When the surface was exposed to the vapor from a mixture with water molefraction, xw, of 0.5, the proton abstraction and the C–O bond cleavage in methanol leading to methoxy (CH3O) and the hydrocarbon ( CH x) species respectively, occurs at a much higher temperature of 180 K, compared to 120 K in the case of pure methanol adsorption. For water-rich mixtures (xw = 0.7 and 0.9) molecular methanol is stabilized on the surface up to 200 K, beyond which water itself desorbs. For xw = 0.7, virtually no dissociation is observed up to 200 K. The increased stability of molecular methanol on the Zn(0001) surface is attributed to the surface-mediated hydrogen bonds that stabilize a water–methanol complex.

scholarly journals Synthesis, thermal, structural and electrical properties of vanadium-doped lithium-manganese-borate glass and nanocomposites

Ionics ◽  
2019 ◽  
Vol 26 (3) ◽  
pp. 1275-1283 ◽  
Author(s):  
Agata Jarocka ◽  
Przemysław P. Michalski ◽  
Jacek Ryl ◽  
Marek Wasiucionek ◽  
Jerzy E. Garbarczyk ◽  
...  
Keyword(s):  
Photoelectron Spectroscopy ◽  
Borate Glass ◽  
Room Temperature ◽  
Melt Quenching ◽  
Initial Value ◽  
X Ray ◽  
Maximum Value ◽  
Structural And Electrical Properties ◽  
Glassy Sample ◽  
Quenching Method

Abstract A glassy sample with a nominal formula LiMn1 − 3x/2VxBO3 (where x = 0.05) was synthesised using the melt-quenching method. Material was characterised by differential thermal analysis (DTA), X-ray diffactometry (XRD) at room temperature and as a function of temperature (HT-XRD), X-ray photoelectron spectroscopy (XPS), impedance spectroscopy (IS) and scanning electron microscopy (SEM). Dependences of glass transition and crystallisation temperatures on the heating rate in DTA experiments were determined. The initial value of electrical conductivity of the glass was 1.4 × 10− 15 Scm− 1. It was significantly increased by a proper thermal nanocrystallisation. The maximum value was higher by 6 orders of magnitude and reached 2.6 × 10− 9 Scm− 1 at room temperature. Expected crystalline phases (i.e. monoclinic and hexagonal LiMnBO3) upon heating were identified and assigned to thermal events observed with DTA. Microstructure of nanocrystalline samples observed by SEM revealed nanocrystalline grains noticeably smaller than 100 nm. Results explaining nanocrystallisation process are coherent.

Drawing Properties of Modified Polyamide 6 Fibers

2011 ◽  
Vol 189-193 ◽  
pp. 3031-3034
Author(s):  
Jen Taut Yeh ◽  
Wei Wei ◽  
Fang Chang Tsai ◽  
Yu Ching Lai
Keyword(s):  
Draw Ratio ◽  
Reactive Extrusion ◽  
Polyamide 6 ◽  
Deformation Mechanisms ◽  
Wide Angle ◽  
X Ray Diffraction ◽  
X Ray ◽  
Drawing Temperature ◽  
Maximum Value ◽  
Spun Fiber

The drawing properties of the modified PA 6 (MPA) fiber specimens prepared at varying drawing temperature were systematically investigated, wherein the MPA resins were prepared by reactive extrusion of PA 6 with the compatibilizer precursor (CP). At any fixed drawing temperature, the achievable draw ratio (Dra) values of MPA as-spun fiber specimens increase initially with increasing CP contents, and then approach a maximum value, as their CP contents are close to the 5 wt% optimum value. The maximum Dra values obtained for MPA as-spun fiber specimens prepared at the optimum CP content reach another maximum as their drawing temperatures approach the optimum drawing temperature at 120 °C. The tenacity and birefringence values of PA 6 and MPA fiber specimens improve consistently as their draw ratios increase. Similar to those found for their achievable drawing properties, the ultimate tenacity and birefringence values of MPA fiber specimens approach a maximum value, as their CP contents and drawing temperatures approach the 5 wt% and 120 °C optimum values, respectively. Investigations including Fourier transform infrared, melt shear viscosity, gel content, thermal and wide angle X-ray diffraction experiments were performed on the MPA resin and/or fiber specimens to clarify the optimum CP content and possible deformation mechanisms accounting for the interesting drawing and ultimate tensile properties found for the MPA fiber specimens prepared in this study.

Crystallization of Cis-Polyisoprenes in a Capillary Rheometer. I

1971 ◽  
Vol 44 (1) ◽  
pp. 1-11 ◽  
Author(s):  
V. L. Folt ◽  
R. W. Smith ◽  
C. E. Wilkes
Keyword(s):  
Natural Rubber ◽  
Atmospheric Pressure ◽  
Room Temperature ◽  
Fibrillar Structure ◽  
Capillary Rheometer ◽  
X Ray ◽  
Complex Morphology ◽  
Structure Changes ◽  
Degree Of Orientation ◽  
Commercial Processing

Abstract Natural rubber is readily crystallized under the pressure and orientation forces existing in a capillary rheometer. The crystallization of natural rubber is readily effected over the temperature range covering commercial processing and fabricating temperatures. The crystalline rubber is stable at atmospheric pressure and room temperature. The observed crystalline melting point increases with increasing crystallization temperatures. Wide angle x-ray pictures show the crystals to be highly oriented in the direction of flow. Electron micrographs of fracture surfaces of the crystalline rubber show the existence of a very complex morphology. Where the degree of orientation is highest, a fibrillar structure is observed parallel to the direction of flow. The fibrillar structure changes to a shish-kebab structure about midway down the capillary. Apparently, a regrouping occurs with chain folded lamellae forming at right angles to the oriented fibrillar type crystals. A rotation of the chain-folded lamellae may occur as the exit end of the capillary is approached.

scholarly journals Effect of the Alloying Metal on the Corrosion Resistance of Pd-Rich Binary Alloys with Pt, Rh, and Ru in Sulfuric Acid

Materials ◽  
2021 ◽  
Vol 14 (11) ◽  
pp. 2923
Author(s):  
Katarzyna Hubkowska ◽  
Julian Kubisztal ◽  
Małgorzata Pająk ◽  
Bożena Łosiewicz ◽  
Andrzej Czerwiński
Keyword(s):  
Corrosion Resistance ◽  
Sulfuric Acid ◽  
Room Temperature ◽  
Electrochemical Impedance ◽  
Binary Alloys ◽  
Roughness Factor ◽  
Kelvin Probe ◽  
X Ray ◽  
The Difference ◽  
Scanning Electron

The paper presents the study of the corrosion resistance of electrodeposited Pd and its binary alloys with Pt, Rh, and Ru on a polycrystalline Au substrate. The corrosion resistance was tested in 0.5 M sulfuric acid at room temperature using potentiodynamic polarization and electrochemical impedance spectroscopy techniques. The morphology/composition and work function values were determined by scanning electron microscopy/energy–dispersive X–ray spectroscopy and scanning Kelvin probe, respectively. The obtained results revealed that the Pd electrode is the most resistant to corrosion, whereas the Pd-Ru electrode is the most susceptible to dissolution. It was found that the corrosion resistance of Pd-binary alloys decrease in the following order: Pd > Pd-Pt > Pd-Rh > Pd-Ru. This effect was assigned mainly to the difference in surface roughness factor of tested electrodes.

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