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In situ condensation of an amorphous cap of the high vapour pressure element (i.e. As, Sb) has been found to provide effective protection of molecular beam epitaxy grown compound semiconductor surfaces against ambient contamination. Most work reported so far relates to arsenic-capped AlGaAs. Detailed investigation with surface sensitive structural (RHEED, LEED) and chemical (XPS) probes confirms t

The surface core-level shift of the Mo(110) surface is determined from high-resolution photoemission measurements of the Mo 3d level. The 3d core-level binding energy of the surface atoms is found to be lowered by 333±10 meV relative to that of the bulk atoms. This result agrees well with semiempirical estimates and with the results of recent ab initio calculations. Decompositions of the spectra i

High-resolution photoemission studies of oxidation of the Al(111) surface have been performed. The appearance of a component at lower binding energy than the metallic bulk Al emission in the Al 2p spectrum at oxygen exposures above ∼50 langmuir (1 L = 10-6 Torr s) is argued to be due to Al atoms which do not bond directly to oxygen atoms at the oxide-metal interface. Low-energy electron diffractio

Layer resolved core level spectra are presented for Na, K, Rb and Cs films on Al(111). From the development of the spectra, it is possible to distinguish emission from alkali atoms at the interface, in the bulk, and at the surface of the adsorbed layers. The core level binding energy shifts are discussed in terms of adhesion and interface segregation energies. It is found experimentally that the A

Low-energy electron diffraction, scanning tunneling microscopy, and photoelectron spectroscopy results from the submonolayer Sm- and Yb-induced surface structures are presented. Several similar metal-induced surface reconstructions are found to exist for Yb and Sm on Si(111) for low submonolayer coverages: 3×2, 5×1, and 7×1. At higher submonolayer coverage, Yb induces a 2×1 reconstruction while Sm

The results of a high resolution photoemission study of the Be(0001) surface carried out at temperatures between 100 and 450 K are reported. At 100 K, three distinctly shifted Be 1s levels, exhibiting shifts of -825, -570, and -265 meV, are revealed and interpreted to originate from the three outermost atomic layers. Identification of two subsurface core level shifts and a first layer surface shif

Taking advantage of the linear polarisation of synchrotron radiation, the polarisation dependence of the O K and Cu L3 X-ray absorption edges has been compared for in situ cleaved Bi2Sr2CaCu2O8 and Bi2Sr2CuO6 single crystals. The X-ray absorption spectra were measured by means of total electron yield detection. The spectra show for both crystals that the lowest unoccupied Cu 3d and O 2p orbitals a

An experimental study was performed to investigate the behavior of inclined negatively buoyant jets. Such jets arise when brine is discharged from desalination plants. A turbulent jet with a specific salinity was discharged through a circular nozzle at an angle to the horizontal into a tank with fresh water and the spatial evolution of the jet was recorded. Four different initial jet parameters we

The silicide formation has been studied in the Mg/Si(111) system by low energy electron diffraction (LEED) and photoelectron spectroscopy. It has been found that an epitaxial Mg2Si silicide is responsible for the ( 2 3√3 × 2 3√3)R30° reconstru system. The thickness of the silicide is limited due to the very low formation temperature for this silicide. The Fermi level is positioned 0.59 ± 0.06 eV a

The photon-induced Auger and photoelectron spectra of the argonlike ions Cl- (in NaCl), K+ (in KCl), Ca2+ (in CaCl2 and CaF2), and Sc3+ (in Sc2O3) have been measured in the vicinity of the L23 absorption edges of these ions. It is shown that at the 2p6→2p53d(4s) resonance a spectator structure appears in the L23M23M23 Auger spectra, which shifts to higher kinetic energies with increasing photon en

The submonolayer adsorption of Na, K, Rb, and Cs on the Al(111) surface at 100 K and at room temperature is investigated by high resolution core level spectroscopy and low energy electron diffraction. It is found that the first alkali atoms on the surface adsorb at surface defects. At higher coverages, up to approximately one third of the maximum submonolayer coverage, alkali atoms adsorbed at def

The essay aims to set out some principles along which church buildings can be investigated as ecclesiological statements. It begins by considering the symbolic nature of all buildings and the general difficulties involved in interpreting them. Then it tackles the more specific difficulties involved in reading churches as ecclesiological statements. The last question considered is why not all churc

Anaerobic co-digestion is an emerging practice at wastewater treatment plants (WWTPs) to improve the energy balance and integrate waste management. Modelling of co-digestion in a plant-wide WWTP model is a powerful tool to assess the impact of co-substrate selection and dose strategy on digester performance and plant-wide effects. A feasible procedure to characterise and fractionate co-substrates

Gaza has several water problems; limited fresh water supply, inefficient water use by the agricultural sector, high water demand, groundwater contamination, seawater intrusion and shortage of electricity. Water and electricity is the first priority for Gaza that will add significant positive values to the Palestinians living in blocked Gaza and easy operation and maintenance of their ongoing and e

We present a widely scalable, high temperature post-growth annealing method for converting ultra-thin films of TiO2 grown by atomic layer deposition to topographically microstructured titanium silicide (TiSi). The photoemission electron microscopy results reveal that the transformation from TiO2 to TiSi at 950 °C proceeds via island formation. Inside the islands, TiO2 reduction and Si diffusion pl

Hierarchical polymer structures such as pNIPAM microgels have been extensively studied for their ability to undergo structural and physical transformations that can be controlled by external stimuli such as temperature, pH or solvent composition. However, a direct three-dimensional visualization of individual particles in-situ has so far been hindered by insufficient resolution, with optical micro

This article examines smallholders’ perceptions of climate variability in two districts in Northern Ethiopia, and the diversification options pursued within and outside agriculture. Meteorological records corroborate smallholders’ belief that temperatures are increasing but do not support assertions that rainfall is decreasing. Farm-level adaptation mainly involves soil and water conservation meas

This project offers an initial evaluation of using the online learning platform Prezi as a tool for increasing student learning within a MA unit in human geography. It does this by comparing the use of Prezi to four other learning activities conducted during the course. The aim of the project is to see whether the use of this technology became an end in itself, thereby distracting students and det

Denna avhandling studerar den moraliska konfliktlinje som genomsyrade den frihetstida politiken åren kring 1740 och som strukturerade politiken enligt en särskilt moralpolitisk logik. Logiken hade sin grund i dels samhällsordningens absoluta och normativt oföränderliga karaktär, dels ett antal djupa förmoderna erfarenheter av och förväntningar på människan som oförmögen att hantera sin fördärvade This thesis examines the moral conflict permeating the politics of Sweden’s Age of Liberty around 1740 – a conflict that also structured the politics of the time in relation to a particular political logic based on moral. This logic was based on the absolute and normatively immutable nature of the social order, but also on a number of deep pre-modern experiences and expectations of man as unable t

Summary The egress strategy in high-rise buildings has traditionally been based on the sole use of stairs for evacuation. However, it is becoming more common to include evacuation elevators in the egress strategy in high-rise buildings. Traditionally, evacuation elevators have not been allowed as an evacuation route, and people have been instructed to not use elevators in case of fire. This means