4 research outputs found

    Frequency of fatigue and its changes in the first 6 months after traumatic brain injury: results from the CENTER-TBI study

    Get PDF
    Background: Fatigue is one of the most commonly reported subjective symptoms following traumatic brain injury (TBI). The aims were to assess frequency of fatigue over the first 6 months after TBI, and examine whether fatigue changes could be predicted by demographic characteristics, injury severity and comorbidities. Methods: Patients with acute TBI admitted to 65 trauma centers were enrolled in the study Collaborative European NeuroTrauma Effectiveness Research in TBI (CENTER-TBI). Subj

    Evaporation of acidic effluent from kraft pulp bleaching, reuse of the condensate and further processing of the concentrate

    No full text
    Abstract Environmental concern and tighter public regulations have created new pressures to reduce effluent loading from kraft pulp bleaching during the past decades. This trend has forced both pulp mills and the related engineering industries to develop and optimise equipment for the pulping processes which fulfils these demands. New pulp washers and washing systems connected with the introduction of new oxygen-based reagents have in particular provided considerably improved tools for reusing process water and thereby essentially reducing effluent discharge or even allowing the implementation of a totally closed water circulation system in kraft pulp bleaching. This study was performed mainly on a laboratory scale at the University of Oulu, but some pilot-scale tests were also performed to confirm the findings of the laboratory-scale evaporation test. Another aim of the pilot-scale tests was to produce enough concentrate for further processing. Conditions were strictly controlled in all the experiments in order to ensure that conclusions could be reached regarding the phenomena examined. The results reported here indicate that the amounts of transition metal ions such as iron, copper or manganese in the process water or water to be recirculated should be kept as low as possible during chlorine dioxide or peracetic acid bleaching, as even a small amount (<<5 ppm) markedly reduced pulp quality and increased reagent consumption. The results also show that evaporation can be used as a method for purifying acidic effluent from both chlorine dioxide and peracetic acid bleaching, and that the resulting condensates were free of transition metals and clean enough for reuse in both bleaching processes. The purity of the condensates was further improved by neutralising the feed pH of the acidic effluents from the bleach plant before evaporation. The results also indicate that the chloride ions in the concentrate arising from evaporation of the acidic effluent from chlorine dioxide bleaching can be removed by a combined acidification/re-evaporation system

    Characterisation of used traction sand for utilization aspects in earth construction based on the requirements of Finnish environmental legislation

    Get PDF
    Abstract Finland launched a new Government Decree, the so-called MARA-regulation, on the utilization of certain wastes in earth construction on 1.1.2018. This statutory regulation sets limit values for the solubility of heavy metals (Sb, As, Ba, Cd, Cr, Cu, Pb, Mo, Ni, Se, Zn, V, Hg), chloride, sulphate, fluoride and dissolved organic carbon, as well as for organic substance (petroleum hydrocarbons, benzene, naphthalene, TEX (toluene, ethylbenzene and xylene), PAH-, phenolic- and PCB-compounds). In this case study, the concentrations of these harmful substances in the used traction sand collected in the city of Kemi, Northern Finland, were lower than their limit values set in the MARA-regulation. Therefore, this residue is a potential material to be used at earth construction sites such as in roads and roadways, in field and embankment structures, as well as in floor structures of industrial or storage buildings. However, if the used traction sand is to be utilized for these kinds of civil engineering purposes, an environmental permit is still needed because this material is not yet included in the scope of the MARA-regulation. This paper also gives an overview of the relevant Finnish environmental legislation on the utilization of wastes as an earth construction material
    corecore