Search results for "SSB"
showing 10 items of 537 documents
Icems and dcems study of Fe layers evaporated onto Al and Si
1990
Thin layers of57Fe (2.5 nm, 10 nm and 70 nm thickness), vacuum evaporated onto Al and Si plates, have been investigated by conversion electron Mossbauer spectroscopy (CEMS). The measurements were performed employing both a proportional counter and a channeltron for conventional and ultrahigh-vacuum integral CEMS (UHV-ICEMS) studies, respectively, and a channeltron for depth-selective CEMS (DCEMS). The phase analysis of the layers on base of experimental results has indicated the presence of metallic iron and one or two iron compounds, ascribed to iron reaction products formed with the residual gas during evaporation. These products are most likely rather stable iron nitrides, are more or le…
Mössbauer and magnetic studies of mixed-valence linear chain compounds: Na3Fe2S4 and Na3Fe2Se4
1986
Mossbauer and magnetic data establish the two compounds Na3Fe2X4(X=S, Se) as mixed-valence linear chain compounds with rapid valence fluctuation. The compounds exhibit 1-dimensional antiferromagnetic coupling within the chains, and below a critical temperature a 3-dimensional ferrimagnetic ordering between the chains.
Time-differential Mössbauer emission spectroscopy: Development of a new spectrometer and first results
1989
A spectrometer for time-differential Mossbauer spectroscopy was developed with a high count rate capability, a good time resolution, and a flexible data handling. Chemical and physical aftereffects following the57Co decay were studied within the cobalt doped systems Turnbulls blue and ZnS.
New time-differential Mössbauer emission measurements on the high-spin→low-spin relaxation in [57Co/Co(phen)3](ClO4)2
1990
Using our new spectrometer for time-differential Mossbauer emission spectroscopy we reinvestigated the high-spin→low-spin relaxation following the57Co(EC)57Fe process in [57Co/Co(phen)3](ClO4)2 (phen=1,10-phenanthroline). In contrast to former investigations we found a temperature dependent initial population less than 1 for the metastable high-spin states. The results and the data evaluation method are presented.
Study of very thin oxide layers by conversion and Auger electrons
1990
Oxidic layers as thin as 20–30 A on α-Fe and stainless steel are studied by57Fe-DCEMS with K-conversion electrons and ICEMS. No indication of a vanishingf-factor could be found. Mossbauer spectra, recorded by use of LMM-Auger electrons (AEMS) and by electrons emitted with energies below 15 eV (LEEMS), contain information on the surface layer as well as on the bulk material, showing that part of these electrons are due to secondary effects and the high escape depths of K-conversion electrons.
Farocki e Fassbinder: l'eredità contrastata del Nuovo Cinema Tedesco
2014
Il saggio ripercorre alcune delle tappe fondamentali del cosiddetto nuovo cinema tedesco, rintracciandone le ragioni dell'origine e l'eridità
The effects of an abrupt increase in taxes on candy and soda in Norway: an observational study of retail sales
2020
Abstract Background Fiscal policies are used to promote a healthier diet; however, there is still a call for real-world evaluations of taxes on unhealthy foods and beverages. We aimed to evaluate the effect of an abrupt increase, of respectively 80 and 40%, in the excising Norwegian taxes on candy and beverages on volume sales of candy and soda. We expected sales to fall. Methods We analyzed electronic point of sale data covering approximately 98% of volume sales of grocery stores in Norway. In two pre-registered models with weekly (log-)sales of taxed candy and soda from 3884 individual stores, we modeled the difference between the jump (discontinuity) in the trend around the time of the i…
MUSIC-based modal channel estimation for wideband OFDM-OQAM
2008
Orthogonal frequency division multiplexing based on offset quadrature amplitude modulation (OFDM-OQAM) over wideband frequency selective multipath channels suffers from inter-symbol interference (ISI) and inter-carrier interference (ICI) that degrade its performance. Channel estimation and equalization are needed to combat these interferences. In this paper a novel channel estimator for passband OFDM-OQAM signaling over wideband multipath channels, which is based on multiple signal classification (MUSIC) with the Spatial Smoothing technique is presented. Numerical simulation results are presented in the low number of subcarriers, i.e. wideband, scenario.
Pamatdatu pārvaldīšana lielapjoma datu sistēmās bāzētās Oracle Hyperion platformā
2017
Maģistra darba pētījumam ir izvēlēta kādas Zviedrijas bankas Hyperion Planning lietotne, kura tiek izmantota darījumu mērķu uzstādīšanai. Autores galvenais mērķis bija uzlabot bankas datu kvalitāti un pamatdatu pārvaldīšanas procesus, lai izvairītos no problēmām saistītām ar datu migrāciju starp lietotnēm, kļūdainām datu kalkulācijām un neprecīzām atskaitēm. Galvenais risinājums tika izstrādāts, izmantojot Oracle DRM pamatdatu pārvaldīšanas rīku, ar kura palīdzību pamatdatu apstrāde tika automatizēta, tādējādi samazinot cilvēciskā faktora risku. Rezultātā risinājums tika ieviests bankas sistēmā, kas tai deva ievērojamus uzlabojumus: tika nodrošināta papildus kvalitātes kontrole un versijpār…
Synthesis, characterization, and in vitro antimicrobial activity of organotin(IV) complexes with triazolo-pyrimidine ligands containing exocyclic oxy…
2005
Abstract Tri-organotin(IV) complexes of the triazolo-pyrimidine derivatives 4,5-dihydro-5-oxo-[1,2,4]triazolo-[1,5 a ]pyrimidine (5HtpO), 4,7-dihydro-5-methyl-7-oxo-[1,2,4]triazolo-[1,5 a ]pyrimidine (HmtpO), and 4,5,6,7-tetrahydro-5,7-dioxo-[1,2,4]triazolo-[1,5 a ]pyrimidine (H 2 tpO 2 ), and the diorganotin derivative n -Bu 2 Sn(tpO 2 ), were synthesized and characterized by means of infrared and 119 Sn Mossbauer spectroscopy. In all the complexes obtained the triazolopyrimidines act as multidentate ligands producing polymeric structures. A trigonal bipyramidal arrangement of the ligands around the tin atom is proposed for triorganotin(IV) derivatives, with organic groups on the equatoria…