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Fine mode particulate sulphur in the tropopause region measured from intercontinental flights (CARIBIC)

Here the first systematic study of the concentration of particulate sulphur in the upper troposphere and lower stratosphere is presented. The measurements were undertaken in the CARIBIC programme during intercontinental flights from a commercial aircraft, which was equipped with an aerosol inlet and a research payload in the cargo bay. Aerosol samples were collected and analysed for elemental comp

Blended learning för utveckling av lärarkompetens

Vad är blended learning? Hur kan lärares kompetens inom blended learning utvecklas? Och hur kan blended learning i sin tur främja utvecklingen av pedagogisk kompetens? I denna rapport redovisas det pedagogiska utvecklingsprojektet Blended learning för utveckling av lärarkompetens som belyser och diskuterar dessa frågor. Projektets avsikt har varit att utveckla, introducera och analysera effekterna

Methodology to estimate the transfer function of individual differential mobility analyzers

A method to estimate the nonideal features of the transfer function of individual differential mobility analyzers (DMA) was developed and tested experimentally. This was up to now an unsolved problem, which is important for the precision in DMA measurements. The method involves three DMAs of unknown characteristics, which are used in three rounds of experiments with two DMAs according to a fixed s

MAX IV Photocathode Gun Laser System Specification and Diagnostics

The MAXIV injector has two guns - a thermionic used for ring injections, and a photocathode used for short pulse facility operation. A commercial Ti:sapphire laser from KMLabs drives the copper based photocathode gun. It has been running without major issues for more than 3 years. The laser delivers up to §I{500}{\textmu J} on the cathode at the third harmonic, §I{263}{nm}, via a vacuum laser tran

Pulse shaping at the MAX IV photoelectron gun laser

A motivation for the development of a versatile, programmable source of shaped picosecond pulses for use in photocathode electron gun preinjectors is presented. We present the experimental setup for arbitrary longitudinal pusle shaping of the MAX IV photocathode gun laser. The setup consists of a grating-based Fourier-domain shaper capable of stretching the pulses directly in the UV domain. Prelim

The New MAX IV Gun Test Stand

The gun test stand from MAX-Lab has been upgraded and moved to a new facility at the MAX IV Laboratory. The new test stand will reuse parts of the equipment from the old test stand but a number of improvements to the setup are be made. In this paper we report on the design of the new gun test stand, research plans in the near future as well as planned and possible future research topics..

Emittance improvements in the MAX IV photocathode injector

The MAX IV injector design predicts a beam with 100 pC of charge and an emittance lower than 1 mm mrad. The photocathode pre-injector is based on the now close to standard 1.6-cell gun adapted to 2.9985 GHz, in combination with a Ti:Sapphire laser system. This system reaches the requirements of the injector operation for the SPF, but can be tuned beyond specifications to open up new operation mode

Modelling cloud processing of aerosol during the ACE-2 HILLCLOUD experiment

A numerical model has been used to simulate the conditions observed during the ACE-2 Hillcloud experiment and to study the processes which may be taking place. The model incorporates gas phase chemistry of sulphur and nitrogen compounds upstream of the cloud, and the interaction of aerosol, precursor trace gases and oxidants within the cloud. Gas phase and aerosol inputs to the model have been pro

Hygroscopic properties of aerosol particles in the northeastern Atlantic during ACE-2

Measurements of the hygroscopic properties of sub-micrometer atmospheric aerosol particles were performed with hygroscopic tandem differential mobility analysers (H-TDMA) at 5 sites in the subtropical north-eastern Atlantic during the second Aerosol Characterization Experiment (ACE-2) from 16 June to 25 July 1997. Four of the sites were in the marine boundary layer and one was, at least occasional

ACE-2 HILLCLOUD. An overview of the ACE-2 ground-based cloud experiment

The ACE-2 HILLCLOUD experiment was carried out on the island of Tenerife in June-July 1997 to investigate the interaction of the boundary layer aerosol with a hill cap cloud forming over a ridge to the north-east of the island. The cloud was used as a natural flow through reactor to investigate the dependence of the cloud microphysics and chemistry on the characteristics of the aerosols and trace

Characteristics of haze, mist and fog

An aerosol and fog data set from a field experiment in November 1994 at San Pietro Capofiume, Northern Italy was analysed. With objective criteria developed from visibility measurements average aerosol characteristics in the dry and wet state were calculated for haze, mist and fog conditions which can be seen as representative for continental air masses in an industrialised region. Dry particle si

Comparison of observed and modeled hygroscopic behavior of atmospheric particles

The hygroscopic behavior of sub-micrometer atmospheric aerosol particles was studied with a Tandem Differential Mobility Analyzer (TDMA) at a field site in the Po Valley, Italy. The measurements were done in a continental polluted aerosol during the CHEMDROP fog and haze field experiment at San Pietro di Capofiume in November 1994. In this study, hygroscopic diameter growth factors of individual p

Changes in submicrometer particle distributions and light scattering during haze and fog events in a highly polluted environment

The changes in submicrometer atmospheric particle size distributions measured with a Differential Mobility Particle Sizer (DMPS) system during a polluted fog experiment during November, 1994 are presented in this study. Results reveal three modes commonly evident in the size distribution (3 < DN < 843 nm) measurements; the ultrafine, Aitken and accumulation with respective geometric diameters, (Dg

The size dependent composition of fog droplets

The size dependency of fog droplet concentration and composition was studied using newly developed droplet impactors during the CHEMDROP campaign in the Po Valley (Italy). A strong size dependency of solute concentrations was measured during several fog episodes. The ionic strength of the droplet solutions varies as a function of droplet diameter, showing maximum values in the 9-19 μm diameter ran

What Kind of Inequality Do You Prefer? Evaluating Measures of Income and Health Inequality Using Choice Experiments

When measuring inequality using conventional inequality measures, ethical assumptions about distributional preferences are often implicitly made. In this paper, we ask whether the ethical assumptions underlying the concentration index for income-related inequality in health and the Gini index for income inequality are supported in a representative sample of the Swedish population using an internet

Overview of the Po valley fog experiment 1994 (CHEMDROP)

The paper presents an outline of the CHEMDROP field experiment, carried out in November 1994 at the field station of S. Pietro Capofiume in the Po Valley, Italy. The main objective of the project was to address the issue of the size-dependent chemical composition of fog droplets, by experimentally investigating the following processes, which are expected to affect (or be affected by) the chemical