Precise Measurement of Activation Parameters for Individual Dislocation Nucleation During in Situ Tem Tensile Testing of Single Crystal Nickel

The hydrogen effect on dislocation nucleation in FeAl single crystal with (100) surface orientation has been examined with the aid of a specifically designed nanoindentation setup for in situ electrochemical experiments. The effect of the electrochemical potential on the indent load–displacement curve, especially the unstable elastic-plastic transition (pop-in), was studied in detail. The observations showed a reduction in the pop-in load for both samples due to in situ hydrogen charging, which is reproducibly observed within sequential hydrogen charging and discharging. Clear evidence is provided that hydrogen atoms facilitate homogeneous dislocation nucleation.

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In situ observation of dislocation nucleation and escape in a submicrometre aluminium single crystal

Nature Materials ◽

10.1038/nmat2370 ◽

2009 ◽

Vol 8 (2) ◽

pp. 95-100 ◽

Cited By ~ 314

Author(s):

Sang Ho Oh ◽

Marc Legros ◽

Daniel Kiener ◽

Gerhard Dehm

Keyword(s):

Single Crystal ◽

Dislocation Nucleation ◽

In Situ Observation

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In situ micro tensile testing of He+2 ion irradiated and implanted single crystal nickel film

Acta Materialia ◽

10.1016/j.actamat.2015.08.028 ◽

2015 ◽

Vol 100 ◽

pp. 147-154 ◽

Cited By ~ 45

Author(s):

Ashley Reichardt ◽

Mihail Ionescu ◽

Joel Davis ◽

Lyndon Edwards ◽

R.P. Harrison ◽

...

Keyword(s):

Single Crystal ◽

Tensile Testing ◽

Nickel Film

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Structure of Palladium Single-Crystal Films Prepared by Flash Evaporation onto (001) NaCl Substrates

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100069272 ◽

1970 ◽

Vol 28 ◽

pp. 456-457

Author(s):

L. E. Murr ◽

G. Wong

Keyword(s):

Single Crystal ◽

High Vacuum ◽

Ultra High Vacuum ◽

High Rate ◽

Flash Evaporation ◽

Optimum Load ◽

Single Crystal Films ◽

Crystal Films ◽

A Current

Palladium single-crystal films have been prepared by Matthews in ultra-high vacuum by evaporation onto (001) NaCl substrates cleaved in-situ, and maintained at ∼ 350° C. Murr has also produced large-grained and single-crystal Pd films by high-rate evaporation onto (001) NaCl air-cleaved substrates at 350°C. In the present work, very large (∼ 3cm2), continuous single-crystal films of Pd have been prepared by flash evaporation onto air-cleaved (001) NaCl substrates at temperatures at or below 250°C. Evaporation rates estimated to be ≧ 2000 Å/sec, were obtained by effectively short-circuiting 1 mil tungsten evaporation boats in a self-regulating system which maintained an optimum load current of approximately 90 amperes; corresponding to a current density through the boat of ∼ 4 × 104 amperes/cm2.

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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

10.26434/chemrxiv.11345063.v2 ◽

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 MgCl2·7H2O 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.

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In-situ stabilization of silver nanoparticles in polymer hydrogels for enhanced catalytic reduction of macro and micro pollutants

Zeitschrift für Physikalische Chemie ◽

10.1515/zpch-2020-1721 ◽

2020 ◽

Vol 0 (0) ◽

Author(s):

Luqman Ali Shah ◽

Rida Javed ◽

Mohammad Siddiq ◽

Iram BiBi ◽

Ishrat Jamil ◽

...

Keyword(s):

Catalytic Reduction ◽

Thermo Gravimetric Analysis ◽

Activation Parameters ◽

Reduction Reaction ◽

Gravimetric Analysis ◽

X Ray Diffraction ◽

In Situ Stabilization ◽

Hybrid Hydrogels ◽

Kinetics Of

AbstractThe in-situ stabilization of Ag nanoparticles is carried out by the use of reducing agent and synthesized three different types of hydrogen (anionic, cationic, and neutral) template. The morphology, constitution and thermal stability of the synthesized pure and Ag-entrapped hybrid hydrogels were efficiently confirmed using scanning electron microscopy (SEM), Fourier transform infrared (FTIR) spectroscopy, X-ray diffraction (XRD) and thermo gravimetric analysis (TGA). The prepared hybrid hydrogels were used in the decolorization of methylene blue (MB) and azo dyes congo red (CR), methyl Orange (MO), and reduction of 4-nitrophenol (4-NP) and nitrobenzene (NB) by an electron donor NaBH4. The kinetics of the reduction reaction was also assessed to determine the activation parameters. The hybrid hydrogen catalysts were recovered by filtration and used continuously up to six times with 98% conversion of pollutants without substantial loss in catalytic activity. It was observed that these types of hydrogel systems can be used for the conversion of pollutants from waste water into useful products.

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Laser damage mechanism and in-situ observation of stacking fault relaxation in β-Ga2O3 single crystal by EFG method

CrystEngComm ◽

10.1039/d1ce00131k ◽

2021 ◽

Author(s):

Bo Fu ◽

Gaohang He ◽

Wenxiang Mu ◽

Yang Li ◽

Boyuan Feng ◽

...

Keyword(s):

Single Crystal ◽

Light Field ◽

Damage Mechanism ◽

Stacking Fault ◽

High Light ◽

Laser Damage ◽

In Situ Observation ◽

Structure Destruction

We designed an original and effective method to study the laser damage mechanism of β-Ga2O3 single crystal grown by edge-defined film-fed growth (EFG). The structure destruction under high light field...

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