7,109 research outputs found
A Graphene Field-Effect Device
In this letter, a top-gated field effect device (FED) manufactured from
monolayer graphene is investigated. Except for graphene deposition, a
conventional top-down CMOS-compatible process flow is applied. Carrier
mobilities in graphene pseudo-MOS structures are compared to those obtained
from top-gated Graphene-FEDs. The extracted values exceed the universal
mobility of silicon and silicon-on-insulator MOSFETs.Comment: 12 pages, 3 figure
Ferromagnetism and temperature-dependent Electronic Structure of hcp Gadolinium
We use a combination of a many-body model analysis with an ab initio band
structure calculation to derive the temperature dependent electronic
quasiparticle structure of the rare-earth metal Gadolinium. As a local-moment
system Gd is properly represented by the ferromagnetic (multiband)
Kondo-lattice model (s-f (d-f) model). The single-particle part of the
model-Hamiltonian is taken from an augmented spherical wave (ASW) band
calculation. The proposed method avoids the double counting of relevant
interactions by exploiting an exact limiting case of the model and takes into
account the correct symmetry of atomic orbitals. The a priori only weakly
correlated 5d conduction bands get via interband exchange coupling to the
localized 4f levels a distinct temperature dependence which explains by a
Rudermann-Kittel-Kasuya-Yosida (RKKY) -type mechanism the ferromagnetism of Gd.
We get a self-consistently derived Curie temperature of 294.1 K and a
T=0-moment of 7.71 , surprisingly close to the experimental
values. The striking induced temperature-dependence of the 5d conduction bands
explains respective photoemission data. The only parameter of the theory
(interband exchange coupling J) is uniquely fixed by the band calculation.Comment: 12 pages, 9 figure
Microstructural characterization of AISI 431 martensitic stainless steel laser-deposited coatings
High cooling rates during laser cladding of stainless steels may alter the microstructure and phase constitution of the claddings and consequently change their functional properties. In this research, solidification structures and solid state phase transformation products in single and multi layer AISI 431 martensitic stainless steel coatings deposited by laser cladding at different processing speeds are investigated by optical microscopy, Scanning electron microscopy (SEM), energy dispersive spectroscopy (EDS), orientation imaging microscopy (OIM), ternary phase diagram, Schaeffler and TTT diagrams. The results of this study show how partitionless solidification and higher solidification rates alter the microstructure and phase constitution of martensitic stainless steel laser deposited coatings. In addition, it is shown that while different cladding speeds have no effect on austeniteβmartensite orientation relationship in the coatings, increasing the cladding speed has resulted in a reduction of hardness in deposited coatings which is in contrast to the common idea about obtaining higher hardness values at higher cladding speeds.
Method of filling databases of electronic components based on the uniform tables of document parameters
Π Π°ΡΡΠΌΠ°ΡΡΠΈΠ²Π°ΡΡΡΡ Π²ΠΎΠΏΡΠΎΡΡ ΡΠ°Π·ΡΠ°Π±ΠΎΡΠΊΠΈ ΠΌΠ΅ΡΠΎΠ΄ΠΈΠΊΠΈ Π°Π²ΡΠΎΠΌΠ°ΡΠΈΠ·ΠΈΡΠΎΠ²Π°Π½Π½ΠΎΠ³ΠΎ Π½Π°ΠΏΠΎΠ»Π½Π΅Π½ΠΈΡ Π±Π°Π· Π΄Π°Π½Π½ΡΡ
ΡΠ»Π΅ΠΊΡΡΠΎΡΠ°Π΄ΠΈΠΎΠΈΠ·Π΄Π΅Π»ΠΈΠΉ, ΠΎΡΠ½ΠΎΠ²Π°Π½Π½ΠΎΠΉ Π½Π° ΠΎΠ±ΡΠ΅Π΄ΠΈΠ½Π΅Π½ΠΈΠΈ ΡΠ°Π±Π»ΠΈΡ ΠΏΠ°ΡΠ°ΠΌΠ΅ΡΡΠΎΠ² Π½ΠΎΡΠΌΠ°ΡΠΈΠ²Π½ΠΎΠ³ΠΎ Π΄ΠΎΠΊΡΠΌΠ΅Π½ΡΠ°. ΠΠΎΠΊΠ°Π·Π°Π½Ρ Π΅Ρ ΠΎΡΠ½ΠΎΠ²Π½ΡΠ΅ ΡΡΠ°ΠΏΡ ΠΈ ΠΎΡΠΎΠ±Π΅Π½Π½ΠΎΡΡΠΈ. ΠΡΠ΅Π΄Π»ΠΎΠΆΠ΅Π½ΠΎ ΠΎΡΠΎΡΠΌΠ»ΡΡΡ ΡΠ²ΡΠ·ΠΈ ΠΌΠ΅ΠΆΠ΄Ρ ΠΏΠ°ΡΠ°ΠΌΠ΅ΡΡΠ°ΠΌΠΈ ΠΈ ΠΏΡΠ°Π²ΠΈΠ»ΠΎ ΡΠΎΡΠΌΠΈΡΠΎΠ²Π°Π½ΠΈΡ Π½Π°ΠΈΠΌΠ΅Π½ΠΎΠ²Π°Π½ΠΈΡ ΡΠ»Π΅ΠΌΠ΅Π½ΡΠΎΠ² Π² ΡΠ΅ΠΊΡΡΠΎΠ²ΠΎΠΌ ΡΠ°ΠΉΠ»Π΅-ΡΠ°Π±Π»ΠΎΠ½Π΅. ΠΡΠΈΠ²ΠΎΠ΄ΠΈΡΡΡ ΠΏΡΠ΅Π΄Π²Π°ΡΠΈΡΠ΅Π»ΡΠ½Π°Ρ ΠΎΡΠ΅Π½ΠΊΠ° Π²ΡΠ΅ΠΌΠ΅Π½ΠΈ ΠΎΡΠΎΡΠΌΠ»Π΅Π½ΠΈΡ ΡΠ°ΠΉΠ»ΠΎΠ²-ΡΠ°Π±Π»ΠΎΠ½ΠΎΠ² ΡΠ°Π·Π»ΠΈΡΠ½ΡΡ
Π½ΠΎΡΠΌΠ°ΡΠΈΠ²Π½ΡΡ
Π΄ΠΎΠΊΡΠΌΠ΅Π½ΡΠΎΠ². ΠΠΎΠΊΠ°Π·Π°Π½ΠΎ ΠΏΡΠΈΠΌΠ΅Π½Π΅Π½ΠΈΠ΅ΠΌΠ΅ΡΠΎΠ΄ΠΈΠΊΠΈ Π΄Π»Ρ Π°Π²ΡΠΎΠΌΠ°ΡΠΈΡΠ΅ΡΠΊΠΎΠ³ΠΎ Π½Π°ΠΏΠΎΠ»Π½Π΅Π½ΠΈΡ ΡΠ΅Ρ
Π½ΠΎΠ»ΠΎΠ³ΠΈΡΠ΅ΡΠΊΠΈΡ
ΡΠΏΡΠ°Π²ΠΎΡΠ½ΠΈΠΊΠΎΠ².The problems of the development of the methodology for the automated filling of databases of electronic products based on the integration of the parameters tables of the normative document are considered. Its main stages and features are shown. It is proposed to formalize the relationship between the parameters and the rule for the formation of the names of elements in a text file-template. A preliminary estimate of the time for creating template files for various normative documents is given. The application of the technique for automatic filling oftechnological databases is shown
Measurement of Lande g factor of 5D5/2 state of BaII with a single trapped ion
We present the first terrestrial measurement of the Lande g factor of the
5D5/2 state of singly ionized barium. Measurements were performed on single
Doppler-cooled 138Ba+ ions in a linear Paul trap. A frequency-stabilized fiber
laser with nominal wavelength 1.762 um was scanned across the 6S1/25D5/2
transition to spectroscopically resolve transitions between Zeeman sublevels of
the ground and excited states. From the relative positions of the four narrow
transitions observed at several different values for the applied magnetic
field, we find a value of 1.2020+/-0.0005 for g of 5D5/2.Comment: 3 figure
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