First-principles calculations and high thermoelectric performance of La–Nb doped SrTiO3 ceramics

In the present study, we have investigated the structural, electronic, and charge transport properties of pristine, hydrogenated, and oxidized Si2BN monolayers via first-principles calculations based on density functional theory (DFT).

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High-Temperature Brazing Molybdenum

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.586.69 ◽

2012 ◽

Vol 586 ◽

pp. 69-73

Author(s):

Chia Chen Lin ◽

Cheng Han Lee ◽

Ren Kae Shiue ◽

Hsiou Jeng Shy

Keyword(s):

High Temperature ◽

Intermetallic Phase ◽

High Temperature Application ◽

Three Point Bending ◽

Brazed Joints ◽

Temperature Application ◽

Titanium Foils

High-temperature brazing molybdenum using palladium and titanium foils have been investigated in the experiment. Successful brazed joints are achieved from using the palladium filler foil. Brazed joints are fully dense and free of any intermetallic phase. Three point bending strengths of 246 and 233 MPa are obtained from joints using 100 m thick palladium filler foil brazed at 1580 and 1610 oC for 600 s, respectively. The application of palladium filler foil shows potential in brazing molybdenum for high-temperature application.

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Technology of Latent Heat Storage for High Temperature Application: A Review

ISIJ International ◽

10.2355/isijinternational.50.1229 ◽

2010 ◽

Vol 50 (9) ◽

pp. 1229-1239 ◽

Cited By ~ 119

Author(s):

Takahiro Nomura ◽

Noriyuki Okinaka ◽

Tomohiro Akiyama

Keyword(s):

High Temperature ◽

Latent Heat ◽

Heat Storage ◽

High Temperature Application ◽

Latent Heat Storage ◽

Temperature Application

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Defect Complexes and Non-Equilibrium Processes Underlying the P-Type Doping of GaN

MRS Proceedings ◽

10.1557/proc-537-g5.3 ◽

1998 ◽

Vol 537 ◽

Author(s):

Fernando A. Reboredo ◽

Sokrates T. Pantelides

Keyword(s):

High Temperature ◽

Experimental Evidence ◽

First Principles ◽

Final Anneal ◽

First Principles Calculations ◽

Defect Complexes ◽

Equilibrium Processes ◽

Open Questions ◽

High Temperature Anneal ◽

P Type

AbstractIt is well known that hydrogen plays a key role in p-type doping of GaN. It is believed that H passivates substitutional Mg during growth by forming a Mgs-N-Hi complex; in subsequent annealing, H is removed, resulting in p-type doping. Several open questions have remained, however, such as experimental evidence for other complexes involving Mg and H and difficulties in accounting for the relatively high-temperature anneal needed to remove H. We present first principles calculations in terms of which we show that the doping process is in fact significantly more complex. In particular, interstitial Mg plays a major role in limiting p-type doping. Overall, several substitutional/interstitial complexes form and can bind H, with vibrational frequencies that account for hitherto unidentified observed lines. We predict that these defects, which limit doping efficiency, can be eliminated by annealing in an atmosphere of H and N prior to the final anneal that removes H.

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