TEM observation and in situ compression tests of transition alumina prepared by high pressure compaction at room temperature

2021 ◽  
Author(s):  
Lucile JOLY-POTTUZ ◽  
Keyword(s):  
High Pressure ◽  
Room Temperature ◽  
Compression Tests ◽  
Transition Alumina

Single Crystal Growth of High-Pressure Phases of Ice and Salt Hydrate Far Below the Original Melting Point by Mixing Alcohol: Crystal Structure Determination of Magnesium Chloride Heptahydrate

2020 ◽  
Author(s):  
Keishiro Yamashita ◽  
Kazuki Komatsu ◽  
Hiroyuki Kagi
Keyword(s):  
Crystal Structure ◽  
High Pressure ◽  
Crystal Growth ◽  
Single Crystal ◽  
Room Temperature ◽  
Growth Technique ◽  
Salt Hydrate ◽  
X Ray

An crystal-growth technique for single crystal x-ray structure analysis of high-pressure forms of hydrogen-bonded crystals is proposed. We used alcohol mixture (methanol: ethanol = 4:1 in volumetric ratio), which is a widely used pressure transmitting medium, inhibiting the nucleation and growth of unwanted crystals. In this paper, two kinds of single crystals which have not been obtained using a conventional experimental technique were obtained using this technique: ice VI at 1.99 GPa and MgCl<sub>2</sub>·7H<sub>2</sub>O at 2.50 GPa at room temperature. Here we first report the crystal structure of MgCl2·7H2O. This technique simultaneously meets the requirement of hydrostaticity for high-pressure experiments and has feasibility for further in-situ measurements.

scholarly journals Drop of Pressure Behavior of Open-Cell Aluminum Foams at High Pressure Flow

2021 ◽  
Vol 19 (6) ◽  
pp. 603-621
Author(s):  
Manuel F. Azamar ◽  
Ignacio A. Figueroa ◽  
Gonzalo Gonzalez ◽  
Ismeli Alfonso
Keyword(s):  
High Pressure ◽  
Room Temperature ◽  
Critical Conditions ◽  
Physical Parameters ◽  
Compression Tests ◽  
Aluminum Foams ◽  
Open Cell ◽  
Geometrical Properties ◽  
Pressure Behavior ◽  
Structural Capacity

Open-cell aluminum foams were produced by the replication technique in three different pore sizes, ranging from 0.71 to 4.75 mm. The manufactured specimens were physically characterized, determining their porosity, relative density, pores per inch and interconnection windows density. A new experimental design is proposed in order to assess the drop of pressure behavior resulting from the injection of gasoline additive at increasing high pressure intervals, ranging from 200 to 25,000 psi, reproducing the tests at room temperature and 200 °C. The regime governing the flow through the investigated samples was determined as a function of flowrate and the foams physical properties. The structural capacity of open-cell Al foams to conduct highly pressurized flow was evaluated by means of compression tests. It was found that at room temperature, the drop of pressure behavior is strongly associated to physical parameters, whilst at 200 °C, dimensional and geometrical properties are negligible. In addition, in this investigation, it is presumed that the studied foams have the structural capacity to conduct fluids at critical conditions of pressure and temperature.

Single Crystal Growth of High-Pressure Phases of Ice and Salt Hydrate Far Below the Original Melting Point by Mixing Alcohol: Crystal Structure Determination of Magnesium Chloride Heptahydrate

2019 ◽  
Author(s):  
Keishiro Yamashita ◽  
Kazuki Komatsu ◽  
Hiroyuki Kagi
Keyword(s):  
Crystal Structure ◽  
High Pressure ◽  
Crystal Growth ◽  
Single Crystal ◽  
Room Temperature ◽  
Growth Technique ◽  
Salt Hydrate ◽  
X Ray

An crystal-growth technique for single crystal x-ray structure analysis of high-pressure forms of hydrogen-bonded crystals is proposed. We used alcohol mixture (methanol: ethanol = 4:1 in volumetric ratio), which is a widely used pressure transmitting medium, inhibiting the nucleation and growth of unwanted crystals. In this paper, two kinds of single crystals which have not been obtained using a conventional experimental technique were obtained using this technique: ice VI at 1.99 GPa and MgCl<sub>2</sub>·7H<sub>2</sub>O at 2.51 GPa at room temperature. Here we first report the crystal structure of MgCl2·7H2O. This technique simultaneously meets the requirement of hydrostaticity for high-pressure experiments and has feasibility for further in-situ measurements.

Texture Evolution of Magnesium Single Crystals Deformed by High-Pressure Torsion

2008 ◽  
Vol 584-586 ◽  
pp. 263-268 ◽  
Author(s):  
Bartlomiej J. Bonarski ◽  
Erhard Schafler ◽  
Borys Mikułowski ◽  
Michael Zehetbauer
Keyword(s):  
High Pressure ◽  
Single Crystals ◽  
Room Temperature ◽  
High Pressure Torsion ◽  
Texture Evolution ◽  
In Situ Stress ◽  
Higher Symmetry ◽  
Strain Measurements ◽  
X Ray

Single crystals of technical purity Magnesium (99.8 wt.%) of initial orientations [ ] 2 1 10 and [ ] 2 2 11 were subjected to HPT deformation at room temperature up to strains of 10. The microstructural evolution has been analyzed by X-ray microtexture investigations and by in-situ stress-strain measurements. The results can be described in terms of shear arising from HPT deformation and - with higher strains - in terms of recrystallization. In crystals with hard orientation[ ] 2 2 11 , these features occur at smaller strains than in crystals with soft orientation [ ] 2 1 10 , i.e. with higher symmetry. In general, the observed textures and strength variations are much stronger than those reported for fcc HPT deformed metals.

HIGH-PRESSURE STRUCTURE STUDY OF CuBa2Ca3Cu4O10 + δ SUPERCONDUCTOR

2005 ◽  
Vol 19 (06) ◽  
pp. 313-316
Author(s):  
X. M. QIN ◽  
Y. YU ◽  
G. M. ZHANG ◽  
F. Y. LI ◽  
J. LIU ◽  
...  
Keyword(s):  
Crystal Structure ◽  
High Pressure ◽  
Room Temperature ◽  
Diamond Anvil Cell ◽  
Structure Study ◽  
X Ray Diffraction ◽  
X Ray ◽  
Diamond Anvil ◽  
Murnaghan Equation

In-situ high-pressure energy dispersive X-ray diffraction measurements on CuBa 2- Ca 3 Cu 4 O 10 + δ (Cu-1234) have been performed by using diamond anvil cell (DAC) device with synchrotron radiation. The results suggest that the crystal structure of Cu-1234 superconductor is stable under pressures up to 34 GPa at room temperature. According to the Birch–Murnaghan equation of state, the bulk modulus is obtained to be ~ 150 GPa.

Size-dependent fracture behavior of GaN pillars under room temperature compression

Nanoscale ◽  
2020 ◽  
Vol 12 (45) ◽  
pp. 23241-23247
Author(s):  
Sufeng Fan ◽  
Xiaocui Li ◽  
Rong Fan ◽  
Yang Lu
Keyword(s):  
Fracture Behavior ◽  
Room Temperature ◽  
Power Device ◽  
Compression Tests ◽  
Single Crystalline ◽  
Size Dependent ◽  
Electron Microscopes

Single crystalline GaN pillars are characterized by in situ compression tests inside electron microscopes, showing distinct size-dependent fracture behavior at room temperature for potential microelectronics, power device and MEMS applications.

scholarly journals Effect of Different Jackfruit Puree Concentrations on the Mechanical Properties of Jackfruit Frozen Confection

2020 ◽  
Vol 1 (1) ◽  
Author(s):  
Amiruddin Mat Johari ◽  
Nur Aliaa Abd Rahman ◽  
Roseliza Kadir Basha ◽  
Azhari Samsu Baharudin ◽  
Mohd Afandi P. Mohammed ◽  
...  
Keyword(s):  
Mechanical Properties ◽  
Stress Relaxation ◽  
Room Temperature ◽  
Relaxation Test ◽  
Compression Stress ◽  
Compression Tests ◽  
Stress Relaxation Test ◽  
Test Device ◽  
Mindstorms Ev3

Jackfruit frozen confection has been mechanically characterised in situ by using compression tests. There are no available studies on the mechanical behaviour of jackfruit frozen confection.   The aim of this study is to identify the mechanical properties of jackfruit frozen confections formulated with different concentrations of jackfruit puree. In this study, the experimental analyses are conducted using a compression test device made from LEGO Mindstorms EV3. The portable device is placed inside a freezer to enable the measurements to be done in low temperatures (-20oC). This is to overcome the limitation of an actual texture analyser which can only be operated at room temperature. The mechanical properties of jackfruit frozen confections at different jackfruit puree concentrations (10%, 20% and 30%) are obtained using the tester and analysed. The tests conducted are uniaxial compression, stress relaxation test and multi-step stress relaxation test. It has been observed that frozen confection with 20% jackfruit puree concentration (JF20) is able to withstand a higher force of compression (27.79kPa) compared to the ones with 10% (JF10) and 30% (JF30) concentrations, at 21.15kPa and 10.48kPa, respectively. For stress relaxation test, JF30 has the highest increasing stress for a strain of 0.05 to 0.2 but it decreases at a strain of 0.3 to 0.4. The results of the multi-step relaxation test on JF30 show agreement with the other two tests where the stress decays starting from the 3rd step until the 5th step of the test. This study provides information on the behaviour of jackfruit frozen confection when subjected to compression and stress that imitates the movement during consumption.

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