Social Loafing in Technology-Supported Teams

This study examines the occurrence of social loafing in technology-supported teams along with methods for diminishing loafing. A controlled laboratory experiment with a 3 × 2 × 2 factorial design is used. The independent variables – feedback, anonymity, and group size – are manipulated experimentally. It was expected that social loafing – a widely observed phenomenon – would indeed occur in technology supported teams. It was also expected that the traditional means of reducing social loafing (i.e., identifiability and feedback) within physical work environments would also have similar effects within technology-supported work environments. As expected, social loafing is found to occur in teams operating in a technology-driven realm. An unexpected finding is that social loafing is measurable only when participants are provided self-feedback. While other forms of feedback have a positive influence on productivity, they fail to reduce this phenomenon, and identifiability of group members is found to have no observable effect on social loafing. Computer Supported Cooperative Work.     

Anodic oxidation of InAlAs

The anodic oxidation of InAlAs is investigated by transmission electron microscopy, Rutherford backscattering spectroscopy and medium energy ion scattering in order to elucidate the mechanism of oxide growth. For this purpose, anodizing was carried out at 5 mA cm⁻² in 0.1 M sodium tungstate and 0.1 M ammonium pentaborate electrolytes at 293 K, which results in relatively efficient film growth over an initial voltage increment of about 70 V. In this period, an amorphous oxide develops with a formation ratio of 2.0 ± 0.2 nm V⁻¹. The film consists mainly of an outer layer of In₂O₃ and an inner layer of units of In₂O₃, Al₂O₃ and As₂O₃, the former representing about 14% of the film. There is suggestion of a fine, intermediate layer containing units of In₂O₃ and Al₂O₃ only. The layering correlates with the bond energies of the cation and oxygen species in the oxide and hence their relative migration rates. Further, for films formed in tungstate electrolyte, tungsten species are incorporated into the outer 40% of the film. Bubbles of oxygen gas are present in the film, probably developed within the In₂O₃ layer. At higher voltages, the film undergoes breakdown, with resulting major changes in the film morphology.     

Improved mechanical and anticorrosion properties of metal oxide-loaded hybrid sol–gel coatings for mild steel in a saline medium

Abstract

A hybrid organic–inorganic sol–gel coating was successfully prepared and subsequently functionalized individually with five different metal oxide additives. The effect of the incorporated oxides on the corrosion protection performance and scratch-resistance properties of the hybrid base coating on mild steel substrates was investigated using electrochemical techniques, namely electrochemical impedance spectroscopy (EIS) and potentiodynamic polarization (PDP) as well as mechanical testing. The steel-coated specimens were immersed in 3.5?wt.% NaCl corrosive medium for two weeks and the results reveal an excellent corrosion protection performance by all coating formulations with a significant high corrosion-resistance property for the sample loaded with molybdenum oxide. Scanning electron microscopy (SEM) images proved the absence of corrosion signs, defects, micro cracks, or delamination on the surface of the coated samples. Compared with the pure hybrid coating, all the metal oxide-embedded coatings (except for the sample loaded with yttrium(III) oxide) show comparable aqueous contact angle values as well as enhanced hardness and adherence properties. No noticeable dependence was observed for the surface roughness parameters as a function of the type of incorporated metal oxide within the sol–gel matrix. Overall, the results of this study demonstrate that metal oxides can be advantageous to the desired properties of hybrid sol–gel coatings applied to steel surfaces.     

Effect of functionalized multiwalled carbon nanotubes on weather degradation and corrosion of waterborne polyurethane coatings

A series of waterborne polyurethane/functionalized multiwalled carbon nanotube (WBPU/f-MWCNT) nanocomposite dispersions was prepared using three defined concentrations of 0.5, 1.0 and 2.0 wt% carboxyl functionalized multiwalled carbon nanotubes (f-MWCNTs). All dispersions were coated on mild steel and exposed under natural weather condition for a maximum of 365 days. Both exposed and unexposed coatings were characterized by potentiodynamic polarization (PDP) and X-ray photoelectron spectroscopy (XPS) analyses. The pristine WBPU coating showed slight degradation and corrosion protection. Inclusion of a higher content of f-MWCNTs significantly improved both the degradation and corrosion protection efficiencies of the coatings. Maximal degradation and corrosion protection was observed when 2.0 wt% f-MWCNT was mixed with WBPU for all of the coatings.     

Special Coils Development at the National High Magnetic Field Laboratory in Toulouse

The Laboratoire National des Champs Magnétiques Intenses (LNCMI) develops different types of coils suited to specific experiments. We present some recent developments on magnet design. Several coils are dedicated to experiments in large scale facilities in France and Switzerland. A 30 T split-pair coil for X-rays diffraction and one 40 T coil for plasma physics at the LULI, two 30 T coils with axial access (one with an conical bore) for X-ray diffraction and absorption experiments. A 40 T wide angle conical access solenoid with a high duty-cycle for neutron scattering at the ILL is being constructed. For use at the installation in Toulouse we have developed, apart from our standard 60 and 70 T coils, several special coils: a coil with a long optical path with 30 T transverse magnetic field and a 90 T long pulse dual coil system.     

Rethinking water reform policies as a ‘wicked problem’ the case of urban water supply in Ghana

Based on the theory of ‘wicked problem’ this paper investigates the causes of unsuccessful reform of urban water utilities in Accra, Ghana. The authors of this paper argue that reforms based only on managerial perspectives are not enough. Taking into account institutional and social issues is a key for the success of such reforms. Donors and international agencies lack such outlook and therefore fail to develop effective water policy reforms in developing countries generally. The paper discusses inter-twined and multi-dimensional institutional constraints that hinder the development of an appropriate approach to water utility reform in Accra.