The intrinsic colors of Type Ia supernovae (SNe Ia) are important to understanding their use as cosmological standard candles. Understanding the effects of reddening and redshift on the observed colors are complicated and dependent on the intrinsic spectrum, the filter curves, and the wavelength dependence of reddening. We present ultraviolet and optical data of a growing sample of SNe Ia observed with the Ultraviolet/Optical Telescope on the Swift spacecraft and use this sample to re-examine the near-UV (NUV) colors of SNe Ia. We find that a small amount of reddening (E(B - V) = 0.2 mag) could account for the difference between groups designated as NUVblue and NUV-red, and a moderate amount of reddening (E(B - V) = 0.5 mag) could account for the whole NUVoptical differences. The reddening scenario, however, is inconsistent with the mid-UV colors and color evolution. The effect of redshift alone only accounts for part of the variation. Using a spectral template of SN2011fe, we can forward model the effects of redshift and reddening and directly compare those with the observed colors. We find that some SNe are consistent with reddened versions of SN2011fe, but most SNe Ia are much redder in the uvw1 - v color than SN2011fe reddened to the same b - v color. The absolute magnitudes show that two out of five NUV-blue SNe Ia are blue because their near-UV luminosity is high, and the other three are optically fainter. We also show that SN. 2011fe is not a "normal" SN Ia in the UV, but has colors placing it at the blue extreme of our sample.

Children are constantly exposed to many chemicals via the products they come in contactwith in their everyday life. One chemical group is phthalates, the most commonly usedplasticisers in the world. Phthalates are used mainly in PVC plastic products like floors, toys,food containers and wallpaper but they are also used in rubber, glue, paint, cables etc. Sincethese chemicals are weakly chemically bound to the PVC they can leak and migrate to the air,food, water and skin. Children are exposed to phthalates mainly through food, but because ofthe hand to mouth behaviour they are also exposed via dust inhalation and dust ingestion.About ten years ago regulations of the most toxic phthalates in toys and child care productswere implemented in the EU and from February 2015 it is a general prohibition for the use ofDEHP (diethylhexyl phthalate), DnBP (di-n-butyl phthalate), DiBP (diisobutyl phthalate) andBBzP (butyl benzyl phthalate). DiNP (diisononyl phthalate) is a relatively new phthalate andit has replaced DEHP to some extent in floors and toys. In phthalate free products DINCH(1,2-cyclohexane dicarboxylic acid diisononyl ester) is one of the plasticizer replacingphthalates. The banned phthalates have been shown to cause adverse effects on reproductionand recent research also investigates links between phthalate exposure and asthma and allergysymptoms in children. More experimental animal studies are needed to further investigate theasthma and allergy correlation. In the present project dust samples were collected from 30 preschool indoor environments inthe Stockholm city area to evaluate the levels of the six substances mentioned and thephthalate DEP (diethyl phthalate). The main aim of this thesis project was to search forrelations and links between the phthalate concentrations in dust and parameters from theindoor environment in preschools. Studied parameters are e.g. construction year, floor type,cleaning routines and quantity of toys and furniture made of plastic or foam. The project wascommissioned by the Swedish EPA and performed at the Institute of Environmental Medicine(IMM) at Karolinska Institutet. A negative relation was found between dust phthalate (DEHP and DnBP) concentrationand construction year. Also rooms with old PVC floors had higher concentrations of DEHPand DnBP in dust than rooms with new PVC floors. There was also a trend that dust frompreschools with PVC floors had higher DiNP concentration than dust from preschools withother floor types. The preschools that used foam mattresses for resting had higher DiNPconcentrations than those with no foam mattresses. Most preschools had new foammattresses, which could indicate a more common use of DiNP in new mattresses or mattress2covers compared to old mattresses that contains more DEHP. The four Waldorf preschoolsthat participated had lower DiNP dust concentrations than the other preschools, which wasexpected since Waldorf orientation includes using as little plastic material as possible. Norelation was found between the phthalate dust concentrations and the quantity of toys made ofsoft plastic in the sampled area. Many preschools had made a plastic inventory where they removed old and soft plastic toysand material. Also many preschools recently replaced old foam mattresses used for resting.This could be due to the big chemical focus in the media and authorities and the brochuresthat have been sent out the last couple of years about what preschool can do to decrease thechemical exposure of children. This interest and awareness seen in the preschools waspositive and hopefully the trend spreads to more preschools. Since children spend a big part oftheir time at preschools it is an important mission for society and the government to decreasethe exposure to hazardous chemicals there. Hopefully what has been done so far is just thebeginning.

Ahvaz, Iran ranks as the most polluted city of the world in terms of PM10 concentrations that lead to deleterious effects on its inhabitants. This study examines diurnal, weekly, monthly and annual fluctuations of PM10 between 2009 and 2014 in Ahvaz. Health effects of PM10 levels are also assessed using the World Health Organization AirQ software. Over the study period, the mean PM10 level in Ahvaz was 249.5 mu g m(-3), with maximum and minimum values in July (420.5 mu g m(-3)) and January (154.6 mu g m(-3)), respectively. The cumulative diurnal PM10 profile exhibits a dominant peak between 08:00-11:00 (local time) with the lowest levels in the afternoon hours. While weekend PM10 levels are not significantly reduced as compared to weekdays, an anthropogenic signature is instead observed diurnally on weekdays, which exhibit higher PM10 levels between 07:00-17:00 by an average amount of 14.2 mu g m(-3) as compared to weekend days. PMio has shown a steady mean-annual decline between 2009 (315.2 mu g m(-3)) and 2014 (143.5 mu g m(-3)). The AirQ model predicts that mortality was a health outcome for a total of 3777 individuals between 2009 and 2014 (i.e., 630 per year). The results of this study motivate more aggressive strategies in Ahvaz and similarly polluted desert cities to reduce the health effects of the enormous ambient aerosol concentrations. (C) 2016 Elsevier B.V. All rights reserved.

We present and analyze the possibility of using optical u-band luminosities to estimate star-formation rates (SFRs) of galaxies based on the data from the South Galactic Cap u. band Sky Survey (SCUSS), which provides a deep u-band photometric survey covering about 5000 deg(2) of the South Galactic Cap. Based on two samples of normal star-forming galaxies selected by the. BPT diagram, we explore the correlations between u-band, H alpha, and IR luminosities by combing SCUSS data with the Sloan Digital Sky Survey and Wide-field Infrared Survey Explorer (WISE). The attenuation-corrected u-band luminosities are tightly correlated with the Balmer decrement-corrected Ha luminosities with an rms scatter of similar to 0.17 dex. The IR-corrected u luminosities are derived based on the correlations between the attenuation of u-band luminosities and WISE. 12 (or 22) mu m luminosities, and then calibrated with the Balmer-corrected Ha luminosities. The systematic residuals of these calibrations are tested against the physical properties over the ranges covered by our sample objects. We find that the best-fitting nonlinear relations are better than the linear ones and recommended to be applied in the measurement of SFRs. The systematic deviations mainly come from the pollution of old stellar population and the effect of dust extinction; therefore,. a. more detailed analysis is needed in future work.

While most filters are made of pleated fibrous media, almost all existing theories of aerosol filtration are developed for flat media placed perpendicular to the air flow. Expressions developed for flat sheet media do not provide accurate information directly useful for designing a pleated filter, and therefore, most progress made in developing pleated filters is based on empiricism. This study is aimed at establishing an enabling knowledge that allows for a better design and optimization of pleated aerosol filters. This study is focused on developing a predictive simulation method that accounts for the influence of a filter’s micro-scale geometric parameters, such as fiber orientation, as well as its macro-scale features, like pleat shape, in predicting the transient pressure drop and collection efficiency with or without the effects of dust loading. The dual-scale simulation method developed in this work is believed to be the only feasible approach for design and optimization of pleated aerosol filters with the current academic-level computational power. Our study is divided into two major tasks of micro- and macro-scale modeling. Our micro-scale studies are comprised of a series of CFD simulations conducted in virtual 2-D or 3-D fibrous geometries that resemble the internal micro-structure of a fibrous medium. These simulations are intended to isolate the effects of each micro structural parameter and study its influence on the performance of the filter medium. In detail, it is intended to propose a method to predict the performance of micro-structures with fiber size distribution. Also, the effects of micro-structural fiber orientation were investigated. Moreover, we offered methodology to predict the performance of noncircular fibers using available analytical expressions for circular fibers. It is shown that the circumscribed circle for a trilobal shaped fiber gives the best prediction for collection efficiency. In macro-scale simulations, on the other hand, the filter medium is treated as a lumped porous material with its properties obtained via micro-scale simulations. Our results showed that more number of pleats helps better performance of pleated filters, however, if the pleat channel becomes blocked by dust cake then this effect is no longer valid.

High-mass stars form within star clusters from dense, molecular regions (DMRs), but is the process of cluster formation slow and hydrostatic or quick and dynamic? We link the physical properties of high-mass star-forming regions with their evolutionary stage in a systematic way, using Herschel and Spitzer data. In order to produce a robust estimate of the relative lifetimes of these regions, we compare the fraction of DMRs above a column density associated with high-mass star formation, N(H-2) > 0.4-2.5 x 10(22) cm(-2), in the "starless" (no signature of stars >= 10 M circle dot forming) and star-forming phases in a 2 degrees x 2(degrees) region of the Galactic Plane centered at l = 30 degrees. Of regions capable of forming high-mass stars on similar to 1 pc scales, the starless (or embedded beyond detection) phase occupies about 60%-70% of the DMR lifetime, and the star-forming phase occupies about 30%-40%. These relative lifetimes are robust over a wide range of thresholds. We outline a method by which relative lifetimes can be anchored to absolute lifetimes from large-scale surveys of methanol masers and UCHII regions. A simplistic application of this method estimates the absolute lifetime of the starless phase to be 0.2-1.7 Myr (about 0.6-4.1 fiducial cloud free-fall times) and the star-forming phase to be 0.1-0.7 Myr (about 0.4-2.4 free-fall times), but these are highly uncertain. This work uniquely investigates the star-forming nature of high column density gas pixel by pixel, and our results demonstrate that the majority of high column density gas is in a starless or embedded phase.

The purpose of this study was to investigate whether the sampling points for measuring airborne dust deposition in the Aitik copper mine - the largest, most effective opencast copper mining in Europe - are well located regarding efficiency to collect monitoring data. Issues that were addressed, among others, include background levels, weather impacts and possible external influence. The study was carried out by analyzing monitoring data covering a seven-year period (2010–2016). Dust-and copper levels, precipitation patterns, wind direction and wind speed were the parameters analyzed. A further look into the sampling points and their actual location in terrain was also made. The result of the study indicates, according to different aspects, on decreasing dust fall levels even though the production has increased. For instance, many of the 19 sampling points shows to have lower dust and copper levels according to a comparison of measurement data from 2010 to 2016. A correlation test showed that precipitation and wind does not have a strong connection to dust levels. On the other hand, wind speed showed to have a strong impact on dust fall levels under periods when the highest dust amounts were measured. Many of the sampling points also showed to have a strong connection to each other. The study concludes that a better dust control programme can be obtained if sampling points are reorganized along with a better method for calculating the dispersion of airborne dust.

We present a comprehensive study of interstellar X-ray extinction using the extensive Chandra supernova remnant (SNR) archive and use our results to refine the empirical relation between the hydrogen column density and optical extinction. In our analysis, we make use of the large, uniform data sample to assess various systematic uncertainties in the measurement of the interstellar X-ray absorption. Specifically, we address systematic uncertainties that originate from (i) the emission models used to fit SNR spectra; (ii) the spatial variations within individual remnants; (iii) the physical conditions of the remnant such as composition, temperature, and non-equilibrium regions; and (iv) the model used for the absorption of X-rays in the interstellar medium. Using a Bayesian framework to quantify these systematic uncertainties, and combining the resulting hydrogen column density measurements with the measurements of optical extinction toward the same remnants, we find the empirical relation N-H = (2.87 +/- 0.12) x 10(21) A(V) cm(-2), which is significantly higher than the previous measurements.

Doctor of Philosophy / Department of Agronomy / DeAnn R. Presley / The abandoned lead (Pb) and zinc (Zn) mines in the Tri-State Mining District of Kansas, Missouri, and Oklahoma have left a legacy of environmental contamination. The waste materials are highly polluted, not only with Pb and Zn, but also cadmium (Cd), which often co-occurs geologically with Zn. The District includes Galena, Kansas, where mines operated between 1876 and 1970. Because limited information exists concerning these mines, three studies were done to characterize them and to investigate a way to remediate the mine waste materials. In the first study, the physical characteristics of the mine waste materials were determined. Plots at Galena that had been established by researchers in May 2006 were sampled in November 2014, 8.5 years after they had received amendments (combinations of compost, lime, and bentonite). Water content, bulk density, infiltration rate, unsaturated hydraulic conductivity, aggregate stability, and particle size distribution were determined. The physical characteristics were highly variable, and the amendments added 8.5 years earlier had no effect on them, except the wind erodible fraction (fraction <0.84 mm in diameter) which was low on treatments that contained bentonite. Because biosolids had never been applied to the mine waste materials at Galena for remediation, an experiment was done to see their effect on plant growth and availability of heavy metals. In 2014 the plots established in 2006 were sampled and a greenhouse study was set up with sudex [Sorghum bicolor (L.) Moench x S. Sudanese (P.) Staph]. Plants grew in the mine waste materials with and without biosolids, and 110-111 days after planting the roots, shoots, and heads with grain were harvested and analyzed for heavy metals. At the same time, the mine waste materials were analyzed for heavy metals, organic carbon (C), nitrogen (N), and phosphorus (P). Plants grew better with biosolids than without biosolids, and only the plants grown with biosolids produced heads . Plants grown without biosolids were stunted and showed severe heavy metal toxicity. Organic C and P were increased in the mine waste materials after the addition of biosolids. Thus, the biosolids increased organic C and P, and they apparently made the heavy metals less available for plant uptake. Many studies have shown the importance of attic dust in documenting metal pollution from a mine. Attic dust in Galena had never been studied, so in a third experiment, 14 dust samples in Galena were collected from interiors (attics and one basement) of nine different buildings using two methods: sweeping with a brush and vacuuming. Dust samples were analyzed for heavy metals (Cd, Cu, Fe, Mn, Ni, Pb, and Zn), mineralogy using X-ray diffraction (XRD), scanning electron microscopy (SEM) in conjunction with energy dispersive spectroscopy (EDX), and particle size. Concentrations of Cu, Fe, Mn, Ni, and Zn in the dust were higher than in the mine waste materials. The results from XRD agreed with those from the SEM-EDX analysis. About 10% of each dust sample contained particulate matter (PM) with a diameter of less than 10 μm (PM₁₀), which is a health concern.

Vid väggsågning i betong uppkommer det mycket damm. Detta damm tas till viss del upp av det vatten som appliceras för att kyla klingan under sågning, vilket leder till en så kallad slurry. Slurryn samt dammet behöver efter avklarad sågning tas upp vilket resulterar i extra arbetsmoment för brukaren av sågen. Det största problemet här är dock det damm som inandas vilket kan leda till sjukdomar såsom silikos. Dessa sjukdomar kommer i framtiden antagligen leda till nya lagkrav kring hur dammet behöver tas hand om innan brukaren kan andas in det. Syftet med studien har därmed varit att utreda hur damm och slurry kan tas upp vid väggsågning. Problemet med väggsågning gentemot andra former av bearbetning i betong har varit svårigheten att täta av gentemot ytan som bearbetning sker i. I fallen med borrning är det tillexempel möjligt att sluta av området och skapa undertryck som då suger upp damm och slurry. För att ge en grund till konceptframtagning utfördes en observation av väggsågning för att skapa förståelse för hur dammet och slurryn beter sig under sågning. Vidare utfördes även en fallstudie för att samla data gällande hur problemet löses idag samt samla punkter från industrin gällande vilka egenskaper lösningen bör ha för att anses som attraktiv i håltagningsindustrin. Utifrån den insamlade empirin genererades koncept med hjälp av brainstorming samt morfologi. Dessa utvärderades sedan med Husqvarna samt med hjälp av Pughs matris där kriterierna för sållningen togs utifrån fallstudiens resultat. Resultatet här blev en pådragsenhet som fäster i klingskyddets befintliga geometrier och tar upp damm och slurry vid den punkt i klingskyddet där den största delen av damm och slurry koncentreras vid sågning. Efter sållningen togs en prototyp fram för att kunna verifiera att damm och slurry kunde tas upp samt för att mäta dess effektivitet. Resultatet av prototyptestet var att konceptet kunde ta upp cirka 23% av slurryn samt markant reducera det synliga dammet. Konceptet kunde därmed anses uppfylla studiens syfte, speciellt gällande dammet då dess skadliga effekter på så sätt kan reduceras. / Wall sawing in concrete generates a lot of dust. The dust is partly collected by the water that is applied as a coolant for the blade, which leads to a mixture called ”slurry”. The slurry as well as the dust needs to be removed after the sawing has been completed, which adds extra steps to the process for the user of the saw. The biggest issue here is the dust that is inhaled by the user, which can lead to diseases such as silicosis . This will probably lead to new regulations regarding how dust is managed, which has been the background of this thesis. The purpose of this study is therefore to evaluate how dust and slurry can be collected during wall sawing. The problem in wall sawing compared to other forms of processing of concrete is the difficulty in creating a seal towards the surface where the processing is being executed. It is for instance easier to create a sealed space around the are of processing during drilling where you can create a vacuum to collect the dust and slurry. An observation was conducted in order to give a basis for how the dust and slurry is acting during sawing. A case study was also executed to gather data regarding how the problem is solved today in the industry as well as to provide intel regarding important attributes that  concepts must have in order to be considered attractive to the industry. Concepts were generated with the collected data as a base through brainstorming and morphology. The concepts were evaluated together with Husqvarna as well as with pugh’s matrix, where the set of criterias had been collected from the case study. The result was a slide on unit that locks to existing geometries and collects dust and slurry at the point where the biggest concentration is achieved during sawing. After the evaluation, a prototype was constructed in order to verify that dust and slurry could be collected and to measure the efficiency of the concept. The result of the test was that the prototype could collect approximately 23% of the slurry as well as significantly reduce the amount of visible dust. The concept could thereby fulfil the purpose of the study, especially regarding the decreasion of dust since the harmful effects of inhalation could be reduced.