Search results for "ALLOYS"
showing 10 items of 1689 documents
Magnetic LB films based upon polyoxometalate clusters and single molecule nanomagnets
1999
Abstract By using the adsorption properties of polyoxometalates such as the ferromagnetic cluster [Co 4 (H 2 O) 2 (PW 9 O 34 ] 10− ) along a positively charged monolayer, we have prepared well organized monolayers of the magnetic polyanions. A similar procedure allowed us to obtain Langmuir-Blodgett films (LB films) based on Mn 12 clusters which show a marked hysteresis
Determination of the first ionization potential of einsteinium by resonance ionization mass spectroscopy (RIMS)
1998
Abstract The first ionization potential of einsteinium (IP Es ) was determined by resonance ionization mass spectroscopy (RIMS) using samples with ≤10 12 atoms of 254 Es ( T 1/2 =276 days). This method is based on the measurement of photoionization thresholds as a function of applied electric field strength, followed by extrapolation to zero field strength to yield IP Es . An atomic beam of Es was created by heating a filament on which einsteinium was electrodeposited from an aqueous solution onto a tantalum backing and covered with titanium metal. Es atoms were ionized via a three-step excitation scheme, and the ions mass-selectively detected in a time-of-flight (TOF) mass spectrometer. Th…
Morphological, electrical and optical properties of organic light-emitting diodes with a LiF/Al cathode and an Al-hydroxyquinoline/diamine junction
2004
Abstract We report the results of the morphological, electrical and optical characterisation of double-layer Alq3-based organic emitting diodes with a lithium fluoride (LiF)/Al cathode. A detailed electron microscopy investigation of their cross-section shows the presence of LiF isolated grains underneath the Al film. Due to the introduction of the LiF layer, luminance was larger than 30,000 cd/m2 at a bias voltage VB=25 V with a maximum external luminous efficiency as large as 46 lm/W at VB=20 V. Performing on/off VB cycles at a very low frequency, each time a recovery of the initial electric and luminous performance was observed. The non-exponential decay of both electric current and lumi…
Inhibitoren der Korrosion 24 (1) - Zur Vergleichbarkeit der Abhängigkeit der Korrosion und Korrosionsinhibierung von der Chloridionen- und Inhibitork…
1979
Die Abhangigkeit der „unter Standardbedingungen” im Schuttelversuch ohne und mit Inhibitoren ermittelten O2-Aufnahmegeschwindigkeit von der Chloridionenkonzentration und der Menge an Eisenpulver wird ermittelt. Ergebnis: die von uns bisher eingehaltenen Standardbedingungen vermitteln an Hand der Schutz werte ein qualitativ verlasliches Bild uber die Inhibitorwirksamkeit. Die Vergleichbarkeit der im Schuttelversuch mit DAB 6-Eisenpulver ermittelten Werte mit den im Schuttelversuch mit 1405-Stahlblechen gefundenen Werten wird durch Versuche mit 1405-Stahlblechraspel abgesichert. Die Korrosionsrate phosphatisierter Stahlbleche 1405 wird durch Inhibitoren mit Phosphonsauregruppen wirksam unterd…
Crystal structures of R2Pd2Pb (R = Y, La, Ce, Pr, Nd, Sm, Gd, Tb, Dy, Ho, Er, Tm, and Lu) compounds
2004
Abstract The crystal structures of the R2Pd2Pb (R=Y, La, Ce, Pr, Nd, Sm, Gd, Tb, Dy, Ho, Er, Tm, and Lu) compounds were determined using X-ray powder diffraction. The investigated compounds crystallize with Mo2FeB2 structure type (space group P4/mbm, Pearson code tP10). The importance of stabilization by polar intermetallic R–Pd bonding is underscored by a bonding analysis derived from electronic band structure calculations.
Computer simulations of electron paramagnetic resonance spectra of P2O5Li2WO4Li2O glasses
1992
Abstract P2O5Li2WO4Li2O glasses have been synthesized and studied over a wide range of compositions. The glasses were characterized mainly by thermodifferential analysis and electron paramagnetic resonance (EPR). The EPR spectra are characterized by the presence of two signals with very different intensities, associated with the Wv (major signal) and Mov (minor signal) paramagnetic centres. The signals have been satisfactorily reproduced by computer simulation, assuming anisotropy in the g values as well as the hyperfine parameters and linewidths. EPR parameters have been extracted and indicate metallic ions located in environments close to square pyramidal.
Determination of the first ionization potential of nine actinide elements by resonance ionization mass spectroscopy (RIMS)
1998
The high sensitivity of RIMS enables the precise determination of the first ionization potential of actinide elements with a sample size of ≤1012 atoms. By multiple resonant laser excitation, the actinide atoms under investigation are ionized in the presence of an electric field, and the ions are mass-selectively detected in a time-of-flight spectrometer. The first ionization potential is obtained by scanning the wavelength of the laser used for the last excitation step across the ionization threshold Wth—indicated by a sudden increase of the ion count rate—at various electric field strengths. Extrapolation of Wth to electric field strength zero leads directly to the first ionization potent…
Über die Inhibitoren der Korrosion IV(1). Versuche zur Unterdrückung der Auflösung von Aluminium durch organische Substanzen in saurer und alkalische…
1965
Oniumsalze oder potentielle Oniumsalze sind wirksame Inhibitoren der Auflosung von Aluminium in Salzsaure. Ihr Schutz ist im alkalischen Medium geringer. Corrosion Inhibitors IV. Investigations into the suppression of the dissolution of aluminium by organic substances in acid and alkaline solution Onium salts or potential onium salts are effective inhibitors in respect of the dissolution of aluminium in hydrochloric acid. In the alkaline medium, the protective effect is less marked.
Atomic and electronic structure of both perfect and nanostructured Ni(111) surfaces: First-principles calculations
2011
article i nfo In this study, we perform first principles simulations on both atomically smooth and nanostructured Ni(111) slabs. The latter contains periodically distributed nickel nanoclusters atop a thin metal film gradually growing from adatoms and serving as a promising catalyst. Applying the generalized gradient approximation within the formalism of the density functional theory we compare the atomic and electronic structures of Ni bulk, as well as both perfect and nanostructured (111) surfaces obtained using two different ab initio approaches: (i) the linear combination of atomic orbitals and (ii) the projector augmented plane waves. The most essential inter-atomic forces between the …
Structurally simple complexes of CO2
2015
The ability to bind CO2 through the formation of low-energy, easily-broken, bonds could prove invaluable in a variety of chemical contexts. For example, weak bonds to CO2 would greatly decrease the cost of the energy-intensive sorbent-regeneration step common to most carbon capture technologies. Furthermore, exploration of this field could lead to the discovery of novel CO2 chemistry. Reduction of complexed carbon dioxide might generate chemical feedstocks for the preparation of value-added products, particularly transportation fuels or fuel precursors. Implementation on a large scale could help to drastically reduce CO2 concentrations in the atmosphere. However, literature examples of weak…