76 research outputs found
Comparative study of the photodeposition of Pt, Au and Pd on pre-sulphated TiO2 for the photocatalytic decomposition of phenol
A comparative study of the photodeposition of Pt, Au and Pd under the same experimental conditions onto pre-sulphated and non-sulphated TiO2 was performed. Morphological and surface characterisation of the samples as well as photocatalytic activity for phenol photooxidation was studied. The influence of sulphate pre-treatment on the deposits size and dispersion onto the TiO 2 surface, and photodeposition yields with the different metals were also analysed. The photocatalytic activity of the doped materials was then investigated, observing that catalytic behaviour can be correlated to physical characteristics of the samples determined by (XRD) X-ray diffraction, (XPS) X-ray photoelectron spectroscopy, (XRF) X-ray fluorescence spectrometry and (TEM) transmission electron microscopy. Sulphate pre-treatment was found to influence both the level of dispersion and the size of metal clusters on the TiO2 surface. Sulphation and metallisation of samples was found to produce a synergistic enhancement in photoactivity for the degradation of phenol. The photoactivity of the catalysts with respect to the doped metal species was ordered Pt > Pd > Au.Ministerio de Ciencia e Innovación CTQ2008-05961-CO2-01Junta de Andalucía P06-FQM-140
Stress and its effects on the employees in a Fast Moving Consumer Goods (FMCG) organisation
Magister Commercii (Industrial Psychology) - MCom (IPS)Employees in the fast moving consumer goods (FMCG) industry are at risk of experiencing high
levels of stress and burnout. Females are especially even more at risk due to their work-load as
well as home-life balance and child rearing responsibilities which could have a spill over effect at
work. Although sources of stress vary for employees due to their work as well as life experiences,
it could still result in negative and detrimental outcomes in their personal as well as professional
lives. Stress could further lead to burnout, resulting in an employee developing a lack of personal
accomplishment, emotional exhaustion (the extent to which emotional resources are depleted), as
well as depersonalisation (negative, cynical attitudes and feelings towards others).
This study highlights the significant relationship between occupational stress and burnout as
experienced by males and females working in a factory in the Western Cape.
A sample of 120 employees was selected from a population of 1000 workers in the fast moving
consumer goods industry. For this study, a quantitative research was undertaken, which involved
the use of a probability sampling method. The measuring instruments included the Experience of
Work and Life Circumstances Questionnaire (WLQ) for stress and the construct burnout was
measured with the Maslach Burnout Inventory Human Service (MBI) respectively.
Results were obtained by using the Pearson Correlation Coefficient, Analysis of Variance
(ANOVA) and T-tests. Permission to conduct this research study on employees was obtained from
the management of the factory. Informed consent, as well as anonymity and confidentiality of the
employees' responses were ensured
Hydrothermal preparation of highly photoactive TiO2 nanoparticles
TiO2 nanoparticles have been prepared by amine assisted sol–gel precipitation of Ti4+ aqueous solutions and further hydrothermal treatment.
The effect of different starting acidic solution (nitric, chlorhydric and acetic acids) as well as the addition of triethylamine (TEA) at different pH has
been widely investigated. It has been stated that different amounts of TEA could have interesting effects upon hydrothermal treatment. Surface and
morphological features significantly differ from TiO2 prepared using different synthetic route. In all cases, amine precipitated TiO2 obtained
exhibit high conversion values for phenol photo-oxidation reaction, being in certain conditions higher than that exhibited by TiO2 Degussa P25.
The precipitation of the acetic acidified solution leads to high surface area values and well crystallized anatase with small crystallite size. In
addition, this set of catalysts show the cleanest surface after the hydrothermal treatment. The conjunction of these features would be the
characteristic features responsible of the best photocatalytic activity observed.Peer reviewe
Peru : public strategies for new technologies in rural areas
This advocacy action was carried out by CEPES, AndinaTIC member in Peru, compiling and systematizing documents on Peruvian government ICT projects. This task supplemented the organisation’s ongoing research on connectivity strategies in rural contexts. CEPES questions the governmental initiatives which tend to focus on access to infrastructure. It highlights the importance of taking the communities’ social and cultural diversity into account, which creates both needs and capabilities
Hydrothermal preparation of highly photoactive TiO2 nanoparticles
TiO2 nanoparticles have been prepared by amine assisted sol–gel precipitation of Ti4+ aqueous solutions and further hydrothermal treatment. The effect of different starting acidic solution (nitric, chlorhydric and acetic acids) as well as the addition of triethylamine (TEA) at different pH has been widely investigated. It has been stated that different amounts of TEA could have interesting effects upon hydrothermal treatment. Surface and morphological features significantly differ from TiO2 prepared using different synthetic route. In all cases, amine precipitated TiO2 obtained exhibit high conversion values for phenol photo-oxidation reaction, being in certain conditions higher than that exhibited by TiO2 Degussa P25. The precipitation of the acetic acidified solution leads to high surface area values and well crystallized anatase with small crystallite size. In addition, this set of catalysts show the cleanest surface after the hydrothermal treatment. The conjunction of these features would be the characteristic features responsible of the best photocatalytic activity observed
A coupled wave–3-D hydrodynamics model of the Taranto Sea (Italy): amultiple-nesting approach
Abstract. The present work describes an operational strategy for the development of a multiscale modeling system, based on a multiple-nesting approach and open-source numerical models. The strategy was applied and validated for the Gulf of Taranto in southern Italy, scaling large-scale oceanographic model results to high-resolution coupled wave–3-D hydrodynamics simulations for the area of Mar Grande in the Taranto Sea. The spatial and temporal high-resolution simulations were performed using the open-source TELEMAC suite, forced by wind data from the COSMO-ME database, boundary wave spectra from the RON buoy at Crotone and results from the Southern Adriatic Northern Ionian coastal Forecasting System (SANIFS) regarding sea levels and current fields. Model validation was carried out using data collected in the Mar Grande basin from a fixed monitoring station and during an oceanographic campaign in October 2014. The overall agreement between measurements and model results in terms of waves, sea levels, surface currents, circulation patterns and vertical velocity profiles is deemed to be satisfactory, and the methodology followed in the process can constitute a useful tool for both research and operational applications in the same field and as support of decisions for management and design of infrastructures
Downscaling With an Unstructured Coastal-Ocean Model to the Goro Lagoon and the Po River Delta Branches
The Goro Lagoon Finite Element Model (GOLFEM) presented in this paper concentrates on the high-resolution downscaled model of the Goro Lagoon, along with five Po river branches and the coastal area of the Po delta in the northern Adriatic Sea (Italy) where crucial socio-economic activities take place. GOLFEM was validated by means of validation scores (bias – BIAS, root mean square error – RMSE, and mean absolute error – MAE) for the water level, current velocity, salinity and temperature measured at several fixed stations in the lagoon. The range of scores at the stations are: for temperature between −0.8 to +1.2°C, for salinity from −0.2 to 5 PSU, for sea level 0.1 m. The lagoon is dominated by an estuarine vertical circulation due to a double opening at the lagoon mouth and sustained by multiple sources of freshwater inputs. The non-linear interactions among the tidal forcing, the wind and the freshwater inputs affect the lagoon circulation at both seasonal and daily time scales. The sensitivity of the circulation to the forcings was analyzed with several sensitivity experiments done with the exclusion of the tidal forcing and different configurations of the river connections. GOLFEM was designed to resolve the lagoon dynamics at high resolution in order to evaluate the potential effects on the clam farming of two proposed scenarios of human intervention on the morphology of the connection with the sea. We calculated the changes of the lagoon current speed and salinity, and using opportune fitness indexes related to the clams physiology, we quantified analytically the effects of the interventions in terms of extension and persistence of areas of the clams optimal growth. The results demonstrate that the correct management of this kind of fragile environment relies on both long-term (intervention scenarios) and short-term (coastal flooding forecasts and potential anoxic conditions) modeling, based on a flexible tool that is able to consider all the recorded human interventions on the river connections. This study also demonstrates the importance of designing a seamless chain of models that are capable of integrating local effects into the coarser operational oceanographic models
Observational Evidence of the Basin-Wide Gyre Reversal in the Gulf of Taranto
The paper shows for the first time the observational evidence of basin-wide gyre reversal in the Gulf of Taranto (north-western Ionian Sea in the eastern Mediterranean Sea) by means of two specifically designed in situ oceanographic campaigns (based on CTD and ADCP measurements). The analysis of the in situ data shows a change in circulation from anticyclonic in October 2014 to cyclonic in June\u2013July 2016. Furthermore, long-term (1993\u20132018) analysis using gridded satellite altimetry data in the Gulf of Taranto shows that the cyclonic gyres are more frequent than anticyclonic gyres. The latter occur only for 2 to 3 years at a time in some decades
High resolution multibeam and hydrodynamic datasets of tidal channels and inlets of the Venice Lagoon
Tidal channels are crucial for the functioning of wetlands, though their morphological properties, which are relevant for seafloor habitats and flow, have been understudied so far. Here, we release a dataset composed of Digital Terrain Models (DTMs) extracted from a total of 2,500 linear kilometres of high-resolution multibeam echosounder (MBES) data collected in 2013 covering the entire network of tidal channels and inlets of the Venice Lagoon, Italy. The dataset comprises also the backscatter (BS) data, which reflect the acoustic properties of the seafloor, and the tidal current fields simulated by means of a high-resolution three-dimensional unstructured hydrodynamic model. The DTMs and the current fields help define how morphological and benthic properties of tidal channels are affected by the action of currents. These data are of potential broad interest not only to geomorphologists, oceanographers and ecologists studying the morphology, hydrodynamics, sediment transport and benthic habitats of tidal environments, but also to coastal engineers and stakeholders for cost-effective monitoring and sustainable management of this peculiar shallow coastal system
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