Sosial ulikhet i helse- folkehelseutfordring : en kvalitativ studie med fokus på psykisk helse

Masteroppgave folkehelsevitenskap- Universitetet i Agder, 2014Background: Social inequalities in health are a significant challenge in Norway. To meet these challenges, we need research that can give us better insight and understanding so that we have greater opportunity to prevent and take action. Researches are showing a relationship between socioeconomic factors and mental health, it is therefore desirable to obtain empirical data from people living with such experiences. Purpose and key questions: The purpose of this study is to get insight and understanding of how socioeconomic factors affect people with impaired mental health, capturing their experience is central in this study. The key questions are: 1) How do individuals experience that their reduced economic resources affect their mental health? 2) What gives meanings and strength fore these individuals, and is there something that can be improved? Method and selection: Qualitative research interview was used to collect data from five participants. The participants are individuals who have or have had experience with impaired mental health. They also have or have been active users of low-threshold centers for people struggling with mental health problems in the southern region of Norway. Results: Reduced economic resources is a factor that affects the individual’s mental health in a negative grade, health exacerbation, insecurity, reduced autonomy and increased psychological distress. Activity has a countervailing effect, it provides a meaningful existence and improves or stabilizes the subjective experience of their own mental health. There are indicators that says that information about offers that exist in the community happens by coincidence. Conclusion: Economy is experienced by the individuals as a crucial factor affecting their mental health. The individual’s are experience a meaningful life with socializing and fellowship when they are using the low-threshold center. Lack of information may possibly lead to exclusion of potential users. Keywords: mental health, social inequality, Kjell Underlid, Aron Antonovsky, economy, activity

Ta-ITO Coated Titanium Bipolar Plates for Proton Exchange Membrane Water Electrolyzers

A novel bi-layer coating composed of a tantalum base layer with an Indium Tin Oxide (ITO) top layer was applied to titanium substrates. Samples were polarized ex situ in a parameter study, where the pH, potential and temperature of the electrolyte was altered, as well as the polarization duration. The Interfacial Contact Resistance (ICR) after polarization showed an increase with time for the first 24 h, then stabilized at approx. 30 mΩ cm2. Minor variations were seen in the ICR after polarization at 1.4 VRHE and 2.0 VRHE, but after polarization at 2.5 VRHE and 2.6 VRHE, the ICR increased to 102 mΩ cm2 and 503 mΩ cm2, respectively. X-ray photoelectron spectroscopy (XPS) analysis revealed that the oxygen to metal ratio on the Tantalum- Indium Tin Oxide (Ta-ITO) coated sample surfaces increased with increasing polarization potential. The surfaces of the samples polarized at 2.5 VRHE and 2.6 VRHE showed lower concentrations of oxygen vacancies, an increase in hydroxides and a decrease in metallic character compared to the non-coated and baseline samples. ITO proved to be a promising candidate for use as coating on BiPolar Plates (BPPs) in Proton Exchange Membrane Water Electrolyzers (PEMWEs).publishedVersio

Hvorfor er jeg bedre personlig egnet enn deg? En studie om personlig egnethet

Temaet for denne bacheloroppgaven er personlig egnethet. Problemstillingen er: Hva er personlig egnethet og hvordan vurderes kandidatenes egnethet opp mot hverandre i en ansettelsesprosess? Formålet med studien er finne ut av hva rekrutterings- og seleksjonansvarlige legger i begrepet og hvordan de vurderer egnetheten til kandidatene. Vi valgte å avgrense oppgaven til å undersøke disse forholdene i staten, da offentlig sektor har strengere rammer for ansettelser enn privat sektor. For å svare på dette har vi tatt i bruk kvalitativ metode fordi vi ønsker å beskrive begrepet og vurderingen. Det ble derfor gjennomført seks dybdeintervjuer med personer som har ansvar for rekruttering i ulike sektorer i staten. Motivasjonen bak oppgaven er at vi selv er jobbsøkende og ønsker å finne ut av hva potensielle arbeidsgivere legger i personlig egnethet når de skriver at dette er en del av vurderingen i stillingsannonser. Resultatene våre viser at begrepet personlig egnethet er vagt og vanskelig å sette ord på. Funnene tilsier at begrepet er stillingsspesifikt, men at det er enkelte egenskaper som kan være foretrukket av flere enn andre. Det blir konkludert med at en generell definisjon ikke er hensiktsmessig, men at virksomheter må kunne definere hva det betyr for deres virksomhet og stillinger. Videre viser det seg at vurderingen av kandidaters personlige egnethet ofte er ustrukturert og at de som ansetter i stor grad styres av magefølelsen og intuisjonen. Det konkluderes med at høyere grad av struktur og bruk av metoder med høy validitet kan gjøre vurderingen mer rettferdig for kandidatene og sikre kvalitet for virksomheten som ansetter

Enhanced performance of polybenzimidazole-based high temperature proton exchange membrane fuel cell with gas diffusion electrodes prepared by automatic catalyst spraying under irradiation technique

Gas diffusion electrodes (GDEs) prepared by a novel automatic catalyst spraying under irradiation (ACSUI) technique are investigated for improving the performance of phosphoric acid (PA)-doped polybenzimidazole (PBI) high temperature proton exchange membrane fuel cell (PEMFC). The physical properties of the GDEs are characterized by pore size distribution and scanning electron microscopy (SEM). The electrochemical properties of the membrane electrode assembly (MEA) with the GDEs are evaluated and analyzed by polarization curve, cyclic voltammetry (CV) and electrochemistry impedance spectroscopy (EIS). Effects of PTFE binder content, PA impregnation and heat treatment on the GDEs are investigated to determine the optimum performance of the single cell. At ambient pressure and 160 o C, the maximum power density can reach 0.61 W cm-2, and the current density at 0.6 V is up to 0.38 A cm-2, with H /air and a platinum loading of 0.5 mg cm-2 on both electrodes. The MEA with the GDEs shows good stability for fuel cell operating in a short term durability test.Web of Scienc

Effect of metallacarborane salt H[COSANE] doping on the performance properties of polybenzimidazole membranes for high temperature PEMFCs

[EN] In this paper, a series of composite proton exchange membranes comprising a cobaltacarborane protonated H[Co(C2B9H11)(2)] named (H[COSANE]) and polybenzimidazole (PBI) for a high temperature proton exchange membrane fuel cell (PEMFC) is reported, with the aim of enhancing the proton conductivity of PBI membranes doped with phosphoric acid. The effects of the anion [Co(C2B9H11)(2)] concentration in three different polymeric matrices based on the PBI structure, poly(2,2 '-(m-phenylene)-5,5 '-bibenzimidazole) (PBI-1), poly[2,2 '-(p-oxydiphenylene)-5,5 '-bibenzimidazole] (PBI-2) and poly(2,2 '-(p-hexafluoroisopropylidene)-5,5 '-bibenzimidazole) (PBI-3), have been investigated. The conductivity, diffusivity and mobility are greater in the composite membrane poly(2,2 '-(p-hexafluoroisopropylidene)-5,5 '-bibenzimidazole) containing fluorinated groups, reaching a maximum when the amount of H[COSANE] was 15%. In general, all the prepared membranes displayed excellent and tunable properties as conducting materials, with conductivities higher than 0.03 S cm(-1)above 140 degrees C. From an analysis of electrode polarization (EP) the proton diffusion coefficients and mobility have been calculated.This work was financially supported by the Ministerio de Economia y Competitividad (MINECO) under project ENE/2015-69203-R and by Consejo Nacional de Ciencia y Tecnologia (CONACyT) for the postdoctoral grant to J. O. The technical support of Servei de Microscpia Electrnica at Universitat Politecnica de Valencia and Servei Central d'Instrumentacio Cientifica at Universitat Jaume I is gratefully acknowledged. The authors thanks Prof. Santiago V. Luis (from Universitat Jaume I) and Dr Isabel Fuentes, Prof. Francesc Teixidor and Prof. Clara Vinas (from Instituto de Materiales de Barcelona, CSIC), for supplying the H[COSANE] compound.Olvera-Mancilla, J.; Escorihuela, J.; Alexandrova, L.; Andrio, A.; Garcia-Bernabe, A.; Del Castillo, LF.; Compañ Moreno, V. (2020). Effect of metallacarborane salt H[COSANE] doping on the performance properties of polybenzimidazole membranes for high temperature PEMFCs. Soft Matter. 16(32):7624-7635. https://doi.org/10.1039/d0sm00743aS762476351632https://earthsky.org/earth/atmospheric-co2-record-high-may-2019Steele, B. C. H., & Heinzel, A. (2001). Materials for fuel-cell technologies. Nature, 414(6861), 345-352. doi:10.1038/35104620CLEGHORN, S. (1997). Pem fuel cells for transportation and stationary power generation applications. International Journal of Hydrogen Energy, 22(12), 1137-1144. doi:10.1016/s0360-3199(97)00016-5Wang, Y., Chen, K. S., Mishler, J., Cho, S. C., & Adroher, X. C. (2011). 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Study of the Catalytic Layer in Polybenzimidazole-based High Temperature PEMFC: Effect of Platinum Content on the Carbon Support

International audienceIn this work, the effect of platinum content on the carbon support in commercial catalyst for electrodes to be used in a Polybenzimidazole (PBI)-based PEMFC has been studied. Three contents of platinum on a carbon support were studied (20 %, 40 % and 60 %). In all cases, the same quantity of PBI in the catalyst layer, which is required as a “binder” was used. From Hg porosimetry analyses, pore size distribution, porosity, mean pore size, and tortuosity of all electrodes were obtained. In all cases, a similar electrode mesostructure was observed. The electrochemical characterization was performed by voltamperometric studies, assessing the electrochemical surface area (ESA) of the electrodes, and by impedance spectroscopy (IS), determining the polarization resistance, and by the corresponding fuel cell measurements. The best results were obtained for the electrodes with a content of 40 % of platinum that led to power densities of 0.55 W/cm2 and 0.3 W/cm2 using O2 and air respectively, at 125 ºC. It has been demonstrated that the temperature has a favouring effect on fuel cell performance and flow humidification did not have remarkable effects as it was expected

Tilstedeværende ledelse i en digital tid: Hvordan oppleves det å lede, og å bli ledet, når ledelse må utøves på avstand?

De fleste organisasjoner har de siste årene opplevd utfordringer som pålagt hjemmekontor og det å måtte erstatte fysisk tilstedeværelse med digitale løsninger. Som en konsekvens av disse utfordringene, stilles det krav til lederen som må være tilstedeværende til tross for at ledelse skal utøves på avstand. Det er disse utfordringene som legger grunnlag for oppgavens problemstilling: «Tilstedeværende ledelse i en digital tid: Hvordan oppleves det å lede, og å bli ledet, når ledelse må utøves på avstand?» Basert på tilgjengelig litteratur, er det i tillegg til problemstillingen utformet tre forskningsspørsmål. Disse handler om ivaretakelse av medarbeider og arbeidsmiljø, om implementerte tiltak og om forbedringsmuligheter i organisasjonen den videre undersøkelsen dreier seg om. Formålet med oppgaven er å undersøke hvordan leder har ivaretatt medarbeider og arbeidsmiljø, og hvordan medarbeider har opplevd ivaretakelsen, i tillegg til hvilke tiltak som er blitt implementert og hvilke som eventuelt kan tas med videre inn i normal arbeidshverdag. Til sist er formålet å undersøke hvilke forbedringsmuligheter som finnes. Det er i det videre valgt å gjennomføre en casestudie i den samfunnskritiske funksjonen Redningsselskapet. Resultatene fra undersøkelsen viser at både medarbeidere og arbeidsmiljø i hovedsak er godt ivaretatt. Det er også implementert flere tiltak gjennom perioden med pandemi, blant annet er hjemmekontor en av disse. Funnene viser at informantene opplever en økt fleksibilitet og ønsker å fortsatt benytte seg av ordningen i tiden fremover. Forbedringsmuligheter som nevnes er bedre kommunikasjon, oppfølging, tilrettelegging og det å se og bli sett. Denne avhandlingen tar sikte på å avklare hvordan medarbeidere opplever ledelse, og hvordan lederen opplever å lede, når dette skjer på avstand

Grounding Strategies for High Voltage Shore Connection of Large Passenger Vessels

High voltage shore connection of large passenger vessels is an important way to improve energy efficiency and reduce local and global emissions, as well as noise. However, it is shown that the vessels' steel hulls will act as sacrificial anodes for the grounding systems in the ports, hence accelerated corrosion of the hulls may occur. The required protective earth (PE) conductor between the hull and the grounding system on shore could also introduce touch voltages above 30 V in case of a fault, posing a safety hazard. Based on field measurements and analyses, a grounding strategy with galvanic separation in the low resistance PE conductor is recommended. It is further advised to use active and passive cathodic protection, and to reduce the set point of the impressed current cathodic protection (ICCP) system to approximately 100 mV versus zinc. These measures will reduce the corrosion rate of the vessels' hulls during power delivery from shore, while avoiding transferred touch voltages.Grounding Strategies for High Voltage Shore Connection of Large Passenger VesselsacceptedVersio

Measuring In Situ Interfacial Contact Resistance in a Proton Exchange Membrane Fuel Cell

Interfacial contact resistance (ICR) is one of the remaining hurdles for successful implementation of stainless steel bipolar plates in PEM fuel cells. We have developed a reliable method, using thin gold wires, to measure the interfacial contact resistance between the bipolar plate material and the porous transport layer during fuel cell operation. The ICR values were found to be in the same range as the ICR values measured ex situ after fuel cell operation. Local ex situ ICR measurements on tested plates indicate uneven current distribution during fuel cell operation. Consequently, an average between three measuring points was used for the in situ measurements, which enabled consistent monitoring of the ICR development alongside fuel cell performance. For almost all of the tests, the largest ICR changes took place within the first two hours of operation, showing the importance of early ICR measurements. Non-coated stainless steel and titanium-coated steel BPPs experienced a higher ICR compared to the gold coated stainless steel.publishedVersio