[1] We have used five years of measurements on board the ROCSAT-1 satellite to develop a detailed quiet time global empirical model for equatorial F region vertical plasma drifts. This model describes the local time, seasonal and longitudinal dependence of the vertical drifts for an altitude of 600 km under moderate and high solar flux conditions. The model results are in excellent agreement with measurements from the Jicamarca radar and also from other ground-based and in situ probes. We show that the longitudinal dependence of the daytime and nighttime vertical drifts is much stronger than reported earlier, especially during December and June solstice. The late night downward drift velocities are larger in the eastern than in the western hemisphere at all seasons, the morning and afternoon December solstice drifts have significantly different longitudinal dependence, and the daytime upward drifts have strong wave number-four signatures during equinox and June solstice. The largest evening upward drifts occur during equinox and December solstice near the American sector. The longitudinal variations of the evening prereversal velocity peaks during December and June solstice are anti-correlated, which further indicates the importance of conductivity effects on the electrodynamics of the equatorial ionosphere.

[1] We used equatorial measurements from the ROCSAT-1 satellite to determine the seasonal and longitudinal dependent equatorial F region disturbance vertical plasma drifts. Following sudden increases in geomagnetic activity, the prompt penetration vertical drifts are upward during the day and downward at night, and have strong local time dependence at all seasons. The largest prompt penetration drifts near dusk and dawn occur during June solstice. The daytime disturbance dynamo drifts are small at all seasons. They are downward near dusk with largest (smallest) values during equinox (June solstice); the nighttime drifts are upward with the largest magnitudes in the postmidnight sector during December solstice. During equinox, the downward disturbance dynamo drifts near sunset are largest in the eastern hemisphere, while the late night upward drifts are largest in the western hemisphere. The longitudinal dependence of the disturbance dynamo drifts is in good agreement with results from simulation studies.

[1] We use radar measurements from the Jicamarca Radio Observatory, magnetometer observations from the Pacific sector and ionosonde data from Brazil to study equatorial ionospheric electric fields during the November 2004 geomagnetic storm. Our data show very large eastward and westward daytime electrojet current perturbations with lifetimes of about an hour (indicative of undershielding and overshielding prompt penetration electric fields) in the Pacific equatorial region during the November 7 main phase of the storm, when the southward IMF, the solar wind and reconnection electric fields, and the polar cap potential drops had very large and nearly steady values. This result is inconsistent with the recent suggestion that solar wind electric fields penetrate without attenuation into the equatorial ionosphere for several hours during storm main phase. The largest daytime prompt penetration electric fields (about 3 mV/m) ever observed over Jicamarca occurred during the November 9 storm main phase, when large equatorial electrojet current and drift perturbations were also present in the Pacific and Brazilian equatorial regions. The rise and decay times of these equatorial electric fields were about 20 min longer than of the corresponding solar wind electric fields. The ratios of prompt penetration electric fields and corresponding solar wind electric field changes were highly variable even during the day, and had largest values near dawn. Also, the prompt penetration electric fields did not show polar cap potential drop saturation effects. Our results clearly highlight that the relationships of prompt penetration and solar wind electric fields, and polar cap potentials are far more complex than implied by simple proportionality factors.

ABSTRACT. The formation of particles during cooling of a synthetic ue gas with vapors of sodium and potassium species is studied in a laboratory tubular reactor with laminar ow. It is shown to agree well with a theoretical model for the process. The kinetics of homogeneous nucleation of the pure chloride vapors is described by the classical nucleation theory, adapted to include the participation of stable dimer as well as monomer vapor molecules. The Tolman equation is used to describe the curvature-dependence of the surface tension of small nuclei. The values of the Tolman parameter for NaCl and KCl are determined from the measurements. The homogeneous nucleation of the pure chlorides is suppressed by even relatively small concentrations of foreign seed particles and is therefore unlikely to contribute to the creation of new particles in real ue gases.The addition of SO 2 to the chloride vapor feed, in the presence of oxygen and water vapor, increases the number concentration of ef uent particles signi cantly and affects their composition to include sulphate in addition to chloride. The sulphate content is independent of the peak temperatures of the ue gas but increases with increasing content of oxygen and SO 2 . The study proves that the alkali sulphates are formed by the sulphation of vapor phase rather than solid, alkali chloride. The sulphate vapors are formed in high supersaturation and show a pronounced tendency towards homogeneous nucleation, which is identi ed as the likely source of the submicron particles formed in alkali rich ue gases.

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Information and communication technologies (ICTs) increasingly permeate everyday life in industrialized societies. The aim of this paper is to explore ICT-related transformations of everyday practices and discuss the implications, particularly for residential electricity consumption. The present socio-technical changes are seen in a historical perspective, and it is argued that the integration of ICT into everyday practices can be seen as a new round of household electrification, comparable to earlier rounds that also led to higher electricity consumption. A case study carried out in Denmark in 2007-2008 explores the present changes in everyday life. Based on qualitative interviews, the study focuses on people's ways of integrating ICTs into their everyday practices, on any significant changes in these practices, and on the influence of the changed practices on electricity consumption. The paper concludes with a discussion on the implications for energy policy.

In this article, we provide a conceptual and argumentative framework for studying how Area-based Initiatives (ABIs) can facilitate contact between networks in deprived neighbourhoods and external forms of power (linking social capital). These relations provide the residents and other members of civil society with crucial access to leveraging resources, ideas and information. Although few studies on linking social capital have been carried out in relation to urban regeneration, there is empirical evidence that suggests that it can play a positive role in establishing trust and relations between civil society and a municipality. We set out with a review of how social capital literature has been applied in an urban context, and then demonstrate empirical examples from Denmark of how, in different contexts (village, town and city), ABIs have facilitated processes that generated different forms of social capital (bridging, bonding and linking). The article concludes that ABIs contribute to creating linking social capital, but the extent of the contribution depends on the level of bonding and bridging social capital in the area. We argue that public planners as well as evaluators of the ABIs should increase their awareness about the potentials of an ABI to create linking social capital in deprived neighbourhoods.

The selectivity curves of nylon gillnets for burbot and two groups of Arctic charr of different fatness were found by the Gulland-Harding method. They are compared to the selectivity curves of whitefish, brown trout, and perch. Based upon these curves and the relationships between most efficient mesh size and fish length, the pooled relative efficiency of a geometrical and an arithmetical series of mesh sizes was calculated for salmonids, burbot, and perch. This efficiency of the geometrical series is different for the three groups of fish, but equal for each group over the interval between the modal lengths of the smallest and largest mesh sizes. The efficiency of the arithmetical series is also different for the three groups, increases linearly with fish length, and is valid over the interval between the modal lengths of the second smallest and the second largest mesh sizes. Each series has its special advantages, and both are easily adjusted to the fish length interval of interest. They are especially adapted for the catch of salmonids. For these, the variations of condition factor is more important than any characteristics of the species, and its influence upon the most efficient mesh size to fish length relationship and the pooled relative efficiency of the two series of nets is evaluated.