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Three surface-shifted core levels on Be(0001)

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

Polarisation-dependent X-ray absorption in high- and low-Tc Bi2Sr2Can-1CunO4+2n superconductors

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 Investigation on Inclined Negatively Buoyant Jets

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

Epitaxial silicide formation in the Mg/Si(111) system

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

Autoionization phenomena involving the 2p53d configuration of argonlike ions in ionic solids

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

Alkali metal adsorption on Al(111)

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 church building as an ecclesiological statement : An essay

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

Modelling anaerobic co-digestion in Benchmark Simulation Model No. 2 : Parameter estimation, substrate characterisation and plant-wide integration

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

Mini Projects Solution for Energy, Wastewater and Water for the Gaza Strip, Palestine

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

Fabrication of topographically microstructured titanium silicide interface for advanced photonic applications

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

Superresolution microscopy of the volume phase transition of pNIPAM microgels

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

Climate Variability and Livelihood Diversification in Northern Ethiopia – A Case Study of Lasta and Beyeda Districts

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

What role can Prezi play in students’ learning process?

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

Politikens drivfjäder : Frihetstidens partiberättelser och den moralpolitiska logiken

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

Evacuation experiments in a virtual reality high-rise building : Exit choice and waiting time for evacuation elevators

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

Influence of soil frost on the character and degradability of dissolved organic carbon in boreal forest soils

Recent studies suggest that increases in extent and duration of winter soil frost increases dissolved organic carbon (DOC) concentrations in boreal riparian soils and connected aquatic systems during the subsequent spring and summer. However, little is known about the impact of frost on DOC character and its degradability. We applied three experimental treatments to riparian soils in northern Swed

Training corporate entrepreneurs: an action learning approach

Although training and development is recognized as an important means to nurture corporate entrepreneurs in organizations, extant research has focused primarily on efforts to develop entrepreneurial leaders and nurture business creation in a school or university setting. We report on the findings of an inductive case study of corporate entrepreneurship training in a large multinational corporation

Exploring the functional heterogeneity of the tumor microenvironment

Tumors are complex entities, composed of different functional populations of malignant and stromal cells. There is an emerging importance to understand previously unmapped communication routes between different cell and non-cell compartments of the tumor microenvironment. Targeted drugs have been used for years in an attempt to block essential pathways for tumor growth. Specifically, drugs targeti

Transformation toward an eco-city : Lessons from three Asian cities

This comparative case study of three Asian cities (Penghu in Taiwan, Seoul in South Korea and Tianjin in China) elucidates the effects of different national approaches to eco-city development and the antecedents of the building of an eco-city. To better understand the Asian context, the three Asian cities of interest were compared with two European cities - Freiburg (Germany) and Samsö (Denmark).

Bacterial and fungal growth in burnt acid soils amended with different high C/N mulch materials

Wildfire has become a major disturbance agent in Mediterranean area, with Galicia in the north-west of Spain having the most frequent fires. In order to combat soil erosion, different post-fire stabilization treatments can be applied, like adding different mulch materials. In a laboratory experiment we evaluated the effect of adding plant residues, commonly used in post-fire rehabilitation (wheat