CLEANING HIGH-SPEED MARINE SEPARATORS WITH AN ENVIRONMENTALLY-FRIENDLY CIP AGENT

The present contribution is devoted to the cleaning of high-speed marine separators employing the environmentally-friendly Cleaning In Place (CIP) agent Alpacon Multi Cip Super. For this particular study an Alfa Laval lube oil separator of type S831 on board the ship MS Isabella was dismantled prior to its first CIP treatment since installation and a few of the sludge-coated insert discs were taken as samples for laboratory experiments. Following assembly, the separator was cleaned according to a standard CIP protocol. Back in the laboratory, experiments mimicking the field CIP conditions verified the excellent cleaning results observed by visual inspection out on the ship after the CIP treatment

Comparison of model-based and sensor-based detection of thermal runaway in Li-ion battery modules for automotive application

In recent years, research on lithium-ion (Li-ion) battery safety and fault detection has become an important topic providing a broad range of methods for evaluating the cell state based on voltage and temperature measurements. However, other measurement quantities and close-to-application test setups were only sparsely considered yet, not has been a comparison in between methods. In this work the feasibility of a multi-sensor setup for detection of Thermal Runaway failure of automotive-size Li-ion battery modules have been investigated in comparison to a model-based approach. For experimental validation Thermal Runaway tests were conducted in a close-to-application configuration of module and battery case – triggered by external heating with two different heating rates. By two repetitions of each experiment high accordance of characteristics and results has been achieved and the signal feasibility for fault detection has been discussed. The before published model-based method recognised the thermal fault in the fastest way – significantly previously the required 5 min pre-warning time. This requirement was also achieved with smoke and gas sensors in most test runs. Additional criteria for evaluating detection approaches besides detection time have been discussed to provide a good starting point for choosing a suitable approach dependent on application defined requirements e.g. acceptable complexity

Comparison of model-based and sensor-based detection of thermal runaway in Li-ion battery modules for automotive application

In recent years, research on lithium–ion (Li-ion) battery safety and fault detection has become an important topic, providing a broad range of methods for evaluating the cell state based on voltage and temperature measurements. However, other measurement quantities and close-to-application test setups have only been sparsely considered, and there has been no comparison in between methods. In this work, the feasibility of a multi-sensor setup for the detection of Thermal Runaway failure of automotive-size Li-ion battery modules have been investigated in comparison to a model-based approach. For experimental validation, Thermal Runaway tests were conducted in a close-to-application configuration of module and battery case—triggered by external heating with two different heating rates. By two repetitions of each experiment, a high accordance of characteristics and results has been achieved and the signal feasibility for fault detection has been discussed. The model-based method, that had previously been published, recognised the thermal fault in the fastest way—significantly prior to the required 5 min pre-warning time. This requirement was also achieved with smoke and gas sensors in most test runs. Additional criteria for evaluating detection approaches besides detection time have been discussed to provide a good starting point for choosing a suitable approach that is dependent on application defined requirements, e.g., acceptable complexity

Med uppdraget i alla kanaler. Institutionell logik för strategisk kommunikation på svenska statliga myndigheter.

Abstract Titel: Med uppdraget i alla kanaler -Institutionell logik för strategisk kommunikation på svenska statliga myndigheter Författare: Ulf Nylén Kurs: Examensarbete i medie- och kommunikationsvetenskap, 15 hp, MK 2500 Termin: Vårterminen 2014 Syfte: Syftet uppsatsen är att identifiera tre grundelement i den institutionella ordning som styr den institutionella logiken strategisk kommunikation på svenska statliga myndigheter. Med utgångspunkt i neoinstitutionell organisationsteori och Thorntons (et al. 2012) interinstitutionella system formuleras tre forskningsfrågor: 1. Var hämtar den strategiska kommunikationen på en statlig myndighet sin legitimitet? 2. Genom vad får den strategiska kommunikationen på en statlig myndighet sin auktoritet? 3. Vad är det strategiska syftet för den strategiska kommunikationen på en svensk statlig myndighet? Metod: Kvalitativ induktiv analys av textdokument Material: 37 (N = 37) kommunikationspolicys från svenska statliga myndigheter utvalda ur en databas med totalt 140 liknande dokument. Urvalet sker med stöd av myndigheternas departementstillhörighet för att garantera ämnesbredd. Huvudresultat: Den strategiska kommunikationen på en statlig myndighet får... 1. sin legitimitet genom sin koppling till myndighetens grunduppdrag, 2. sin auktoritet genom att definiera vad som är en strategiskt viktig kommunikationskanal och 3. har som strategiskt syfte att stärka förtroendet för den egna organisationen inom myndighetens egen intressesfär

Ring-opening catalysts for cetane improvement of diesel fuels

The global oil refining industry with its present product distribution essentially shifted towards fuels such as gasoline and diesel will most likely hold the fort for considerable time. However, conditions are changing and refinery survival will very much depend on long-term planning, process and product flexibility and being at the frontiers of refining technology, a technology where catalysts play leading roles. Today oil refiners are faced with the challenge of producing fuels that meet increasingly tight environmental specifications, in particular with respect to maximum sulphur content. At the same time, the average quality of crude oil is becoming poorer with higher amounts of aromatics, heteroatoms (sulphur and nitrogen) and heavy metals. In order to stay competitive, it is of decisive importance for refiners to upgrade dense petroleum fractions of low quality to highly value-added products. A practicable route, for example, is upgrading the catalytic cracking by-product Light Cycle Oil (LCO) into a high-quality diesel-blending component in a two-step catalytic process. In the first step the LCO is hydrotreated over a Pt Pd based acidic catalyst bringing about heteroatom and aromatic reduction and isomerization of C6 to C5 naphthenic structures. In the second step these naphthenic structures are selectively opened over an Ir-based catalyst to improve the cetane value. The present thesis is mainly devoted to the second catalytic step of LCO upgrading and was partly conducted within the framework of the European Union project RESCATS. From the patent literature it is evident that iridium-based catalysts could be good candidates for ring-opening purposes. A literature survey covering ring opening of naphthenic structures made in the beginning of the project (in 2001), showed the need for extending investigations to heavier hydrocarbons, more representative of the diesel fraction than model compounds such as alkylated mono C5 and C6 naphthenic rings frequently employed in previous academic studies. Ring-opening catalysts, mainly Pt-Ir based, were synthesised at KTH by two different techniques: the microemulsion and the incipient wetness techniques. Paper I is a review of the microemulsion technique and its applications in heterogeneous catalysis. Characterization of catalysts was performed employing a multitude of techniques including quantitative TPR, TEM-EDX, XPS, CO FT-IR, NH3-DRIFTS and XRF etc. Catalytic screening at 325 oC and atmospheric pressure with hydrogen and pure indan as model substance was conducted to investigate ring-opening activity in terms of conversion and selectivity to desired cetane-boosting products. This development process is the topic of Papers II-IV. The possible industrial implementation of the best catalyst candidate is demonstrated in Paper V. When designing a catalytic system aimed at refining petroleum, it is crucial to monitor the evolution of the sulphur distribution throughout the different stages of the process so that catalyst properties and reaction parameters may be optimised. The final section of this thesis and Paper VI are devoted to high-resolution sulphur-distribution analysis by means of a sulphur chemiluminescence detector (SCD) following gas chromatographic separation.QC 2010101

Development of ring-opening catalysts for diesel quality improvement

The global oil refining industry with its present shift inproduct distribution towards fuels such as gasoline and dieselwill most likely hold the fort for many years to come. However,times will change and survival will very much depend onprocessing flexibility and being at the frontiers of refiningtechnology, a technology where catalysts play leading roles.Today oil refiners are faced with the challenge to producefuels that meet increasingly tight environmentalspecifications, in particular with respect to maximum sulphurcontent. At the same time, the quality of crude oil is becomingworse with higher amounts of polyaromatics, heteroatoms(sulphur and nitrogen) and heavy metals. In order to staycompetitive, it is desirable to upgrade dense streams withinthe refinery to value-added products. For example, upgradingthe fluid catalytic cracking (FCC) by-product light cycle oil(LCO) into a high quality diesel blending component is a veryattractive route and might involve a two-step catalyticprocess. In the first step the LCO is hydrotreated andheteroatoms are removed and polyaromatics are saturated, in thesecond step naphthenic rings are selectively opened to improvethe cetane number of the final product. The present research is devoted to the second catalytic stepof LCO upgrading and was carried out within the framework of aEuropean Union project entitled RESCATS. From the patent literature it is evident that iridium-basedcatalysts seem to be good candidates for ring-opening purposes.A literature survey covering ring opening of naphthenicmolecules shows the need for extending investigations toheavier model substances, more representative of the dieselfraction than model compounds such as alkylated mono C5 and C6-naphthenic rings frequently employed in academic studies. Ring-opening catalysts, mainly Pt-Ir based, were synthesisedat KTH by two different methods: the microemulsion and theincipient wetness methods. Characterization of the catalystswas performed using a number of techniques including TPR,TEM-EDX, AFM and XPS etc. Catalytic screening at atmosphericpressure using pure indan as model substance was utilized todetect ring-opening activity and the magnitude of selectivityto desired cetane-boosting products. The development of suchring-opening catalysts is the topic of Paper I. When designing a catalytic system aimed at refiningpetroleum, it is crucial to monitor the evolution of thesulphur distribution throughout the different stages of theprocess so that catalyst properties and reaction parameters canbe optimised. The final section of this thesis and Paper II arethus devoted to high-resolution sulphur distribution analysisby means of a sulphur chemiluminescence detector (SCD). Keywords:ring opening, naphthenes, cetane numberimprovement, indan, light cycle oil (LCO), Pt-Ir catalyst,catalyst characterization, aromatic sulphur compounds, GC-SCD,distribution, analysis

Ultraviolett strålning och hälsa : ett kunskapsunderlag

Ultraviolet radiation and health Exposure to ultraviolet radiation can cause adverse effects on skin, eyes, and the immune system. Some effects are acute : they appear after short duration of exposure to ultraviolet radiation. Such effects are erythema, increased pigmentation, photokeratitis and photoconjunctivitis. Other effects such as elastosis and certain forms of skin cancer are regarded as irreversible and appear after chronic exposure. The acute effects and the photoageing of the skin are commonly occurring, while the more serious cancer forms are less common : but their occurrences have increased in recent years. This is considered to be at least partly attributed to an increased exposure to ultraviolet radiation. Thus, there is an obvious need to limit the total exposure to ultraviolet radiation. Internationally, ICNIRP have developed guidelines for the limitation of exposure to ultraviolet radiation. These limitations give individuals with normal sensitivity a protection against acute effects on skin and eyes, and are also thought to protect against some of the long-term effect (e.g. certain cancer forms). Several forms of malignant melanoma are, on the other hand, thought to be a result of single episodes of heavy exposure. High levels of UV radiation can occur within Swedish industry at e.g. welding and UV curing of surface coatings. The possibilities to locally measure and control these levels at a relevant cost have improved during the last decade.Ultraviolett strålning (UV) indelas vanligen i UVA, UVB och UVC. Den dos som ger upphov till en definierad skada kallas tröskeldos. Tröskeldosen plottad som funktion av våglängd benämns aktionsspektrum. Lämplig längsta expositionstid kan beräknas på basis av aktionsspektrum genom att addera de viktade doskomponenterna från varje våglängdsområde i en exponering. UV orsakar skador på lipider och proteiner i cellmembran och inne i cellen samt på DNA. UV har flera olika skadeeffekter på huden som beror på intensitet, exponeringstid och våglängdsområde (UVA eller/och UVB). UV kan skada arvsanlagen i hudens celler samt orsaka hudrodnad, brännskador, elastos (förtjockad och rynkig hy) samt godartade och elakartade former av hudcancer. En liten andel av befolkningen har hud som är abnormt känslig för UV. Hornhinnan blockerar all UV med kortare våglängd än 290 nm. Linsen filtrerar bort merparten av all UV mellan 290-400 nm. En överdos av UV mot ögat ger akut ögonlocksrodnad och svullnad och inflammatorisk reaktion i bindehinna och hornhinna som är reversibel inom 1-2 dygn. Om dosen är mycket hög uppkommer irreversibel grå starr. Långvarig exponering av ögat för UV är associerat till förändringar i bindehinnan, hornhinnan och linsen. Iakttagelser att UV-strålning har en hämmande effekt på immunsystemet har gjorts såväl i djurexperiment som i studier på människor. Solljusexponering reducerade bl a mängden cirkulerande T-lymfocyter och naturliga mördarceller i blodet hos friska kontrollpersoner. De immunhämmande effekterna av UV-strålning kan tänkas ha negativa hälsoeffekter genom att nedsätta motståndskraften för infektioner samt eventuellt främja tumöruppkomst. Det föreligger en individuell variabilitet i känslighet för immunsuppression efter UVB-bestrålning. Den skyddande effekten av solskyddskrämer mot UV-inducerad immunsuppression är fortfarande otillräckligt studerad. Tidigare ansatser att erhålla en bättre kontroll av yrkesmässig exponering för UV-strålning har försvårats av bristen på praktiskt och ekonomiskt försvarbara mätinstrument. Numera finns sådana instrument för mätning av absolutnivåer samt även olika former av billiga och tillförlitliga persondosimetrar vilket kan vara ett alternativ för övervakning av UV-exponering hos utsatta yrkesgrupper. Den i arbetslivet mest frekventa exponeringen för UV-strålning är självfallet utomhusvistelse. Vid inomhusarbete kan dock exponering för väsentligt högre nivåer av UV-strålning uppkomma vid bristande avskärmning av ljuskällan i samband med UV-härdning av akrylatlacker, elektrosvetsning och lasersvetsning. Även lysrör för medicinska UV-behandlingar och ofiltrerade halogenlampor kan medföra höga nivåer

Atrophy of skin-draining lymph nodes predisposes for impaired immune responses to secondary infection in mice with chronic intestinal nematode infection

<div><p>Intestinal nematodes suppress immune responses in the context of allergy, gut inflammation, secondary infection and vaccination. Several mechanisms have been proposed for this suppression including alterations in Th2 cell differentiation and increased Treg cell suppressive function. In this study, we show that chronic nematode infection leads to reduced peripheral responses to vaccination because of a generalized reduction in the available responsive lymphocyte pool. We found that superficial skin-draining lymph nodes (LNs) in mice that are chronically infected with the intestinal nematode <i>Heligmosomides polygyrus</i>, do not reach the same cellularity as worm-free mice upon subsequent BCG infection in the skin. B cells and T cells, all declined in skin-draining LN of <i>H</i>. <i>polygyrus</i>-infected mice, resulting in LNs atrophy and altered lymphocyte composition. Importantly, anti-helminthic treatment improved lymphocyte numbers in skin-draining LN, indicating that time after de-worming is critical to regain full-scale LN cellularity. De-worming, and time for the skin LN to recover cellularity, also mended responses to <i>Bacille Calmette-Guerin</i> (BCG) in the LN draining the footpad injection site. Thus, our findings show that chronic nematode infection leads to a paucity of lymphocytes in peripheral lymph nodes, which acts to reduce the efficacy of immune responses at these sites.</p></div