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No description available.

The Giant Mine near Yellowknife, NWT generated 237 000 tonnes of arsenic-trioxide (As₂O₃)-rich dust as a by-product of gold mining during its years of operation (1948 - 2004). Arsenic trioxide is a relatively soluble form of arsenic (As) and is currently stored in the mine, posing a threat of contamination to the adjacent Great Slave Lake. This research investigates the potential for permanent remediation of the As₂O₃ using sulfidation to transform it to arsenic trisulfide (As₂S₃). Knowing that aqueous As₂O₃ readily reacts with sulfide (Ostermeyer, 2021), it was determined that the most practical and effective method to achieve sulfidation of the Giant Mine dust is to first dissolve the As₂O₃ and then conduct the reaction with sulfide. The optimal conditions at which to dissolve As₂O₃ were investigated. The solubility and dissolution rate in water were shown to increase with temperature, with solubility increasing from 185.7 g As₂O₃/kg water at 140 °C to 250.6 g As₂O₃/kg water at 180 °C. Qualitative demonstrations of the rate of dissolution show that ≥ 90 % of the As₂O₃ dissolved within 5 minutes at 140 °C, and 4 minutes at 180 °C; previous research indicates that time to equilibrium is > 24 hours at 60 °C (CANMET, 2000). Reaction of Giant-Mine material in water at elevated temperatures (140 °C - 200 °C) for 10 to 30 minutes consistently resulted in dissolution of approximately 80 wt. % of the initial solid-phase As concentrations, representing almost all the As₂O₃, yielding undissolved residues (≈ 40 wt. % of initial mass). The persistence of As in these residues is likely due to it being hosted in As₂O₃ - Sb₂O₃ solid solutions and low-solubility Fe-oxide phases in the initial sample (CANMET, 2000; Poirier, 2004).

Introduction: This study assessed student perceptions, preparation, and result use strategies of the Pharmacy Curriculum Outcomes Assessment (PCOA). Secondarily, it studied the effect of schools/colleges of pharmacy (S/COP) PCOA management on student perceptions. Methods: A 52-item electronic questionnaire assessed PCOA preparation of final year students, review/use of results, remediation participation, self-reported motivation, and perceptions of the exam's ability to measure PCOA blueprint areas and North American Pharmacy Licensure Examination (NAPLEX)/advanced pharmacy practice experience (APPE) readiness. Programs were given a questionnaire to determine their PCOA practices. Results: The student survey was completed by 341 students (40% response rate). Students prepared very little for the PCOA and few reported participation in PCOA-based remediation (6%). Students perceived the PCOA to measure the four domains moderately well, although administrative sciences were significantly lower. Students reported less confidence in the exam's ability to measure APPE/NAPLEX-readiness. Although few used the PCOA to guide their NAPLEX preparation (18%), they were more likely to do so than for APPEs (4%). Students reported a higher perceived increase in motivation if PCOA results were connected to APPE placement, remediation, and progression as opposed to prizes, rewards, or other recognitions. Conclusion: This is the first multi-institutional study to review student perceptions about the PCOA. These data can be used along with other PCOA data to help schools develop incentive, remediation, and examination administration procedures depending on the programs desired use for the PCOA exam.

For generations, the technological development of the media has changed human behavior, both for the better and for the worse. From having to buy everything in a store to being able to shop through a live-stream. The problem, however, is that there is a lack of research that has touched on this in the Nordic countries. Especially studies that have touched it in a media archeological aspect. In this thesis, I have analyzed liveshopping as a medium by comparing it with TV-shop. This has been done with the help of media archeology/-ecology as a theoretical and methodological framework. Furthermore, the theory has supplemented with the help of remediation and affordance. Together, they form a theory package that complements each other in the thesis' purpose of examining the medium's properties and design, its environment and how it contributes to the individual's behavior. The analysis of the media has been complemented by the multimodal tools. The material consists of seven broadcasts from TVG (TV-shop) and liveshopping-streams from Lyko, Samsung, MQ MARQET and Lensway The result indicates a change in consumer behavior. During the TV-shop we had a behavior of not shopping from home. Which is proven in the media's attempt to attract viewers with cheap prices on the products. In today's liveshopping, reduced prices are not as common. Due to the fact that the audience actively went into the live-stream, it indicates that they do not necessarily watch the broadcast to be able to buy products at cheaper prices. The technological changes of the media have made possible changes in society through our way of consuming and interacting with the content from companies.

The purpose of this study was to develop, implement and test a tool designed to help transient students gain the basic musical knowledge and skills needed to successfully complete a fourth-grade unit of recorder study. The project resulted in the development of a hypermedia-based application. The seven-week study consisted of 49 fourth-grade students. Students were given pitch reading and rhythm pattern identification pre-tests and post-tests. Students participated in weekly tests and tutorial sessions via the hypermedia-based application. At the conclusion of the study, the students were given post-tests and a performance test. The pre-test and post-test scores for the transient and established populations were analyzed. A t-test analysis revealed a significant improvement in the scores of the established and transient populations. It appears that the hyper-media application may be an effective tutorial for transient students.

The mining industry is an important part of the society’s green transition by providing the metals and minerals necessary for an increased electrification. One downside of the mining industry is that the mining operation typically contaminates the land to some degree. Excavation-and-refill is a traditional remediation approach for soil contaminations, a method that often could be very expensive and cause a large amount of greenhouse gas emissions. This study aims to compare different excavation strategies to find out how they affect the sustainability dimensions and the climate. This is done by using two measuring tools: SAMLA for contaminated sites and Carbon footprint of remediations and other groundworks. The results show that the largest greenhouse gas emissions occur when transporting the contaminated soils to the designated landfill. The different excavation approaches have a positive impact primarily on the ecological and social sustainability dimensions, including reducing the risks for the environment and people’s health. To make excavation-and-refill remediations more sustainable the main focus should be towards the largest contributor of greenhouse gas emissions, together with developing the knowledge regarding the climate impact of remediation methods and to improve the knowledge of alternative, more sustainable, remediation methods. Implementation of environmental regulations focusing on remediations could also be an important factor in the transition towards more sustainable remediation methods.

Hydrazine (HZ) and monomethylhydrazine (MMH) are used extensively as hypergolic propellants at Kennedy Space Center. These highly reactive fuels are considered highly toxic, and potentially carcinogenic. Consequently, the transport, handling, and disposal of hydrazines is strictly regulated to protect personnel and the environment. Currently, KSC generates large volumes of hydrazine-laden wastewater for disposal. This waste is contained and shipped on public highways for subsequent disposal by incineration presenting a potentially catastrophic threat to the environment and the general public in the event of an accidental release. Other existing remediation methods include oxidative and reductive pathways as well as biodegradation in fixed film reactors. Each of these methods has associated drawbacks and limitations that make them unsuitable for industrial use. Recently, hydrazine neutralization by reaction with alpha-ketoglutaric acid (AKGA) to form the stabilized pyridazine derivatives PCA and mPCA has been explored. The applicability of this technique for use at KSC has been established and procedural considerations for implementation have been addressed. Experimental evidence based on worst case scenario decontamination processing simulations and reaction characterization has suggested that AKGA can cost effectively function as a drop-in replacement for current neutralizers with minimal modification to existing infrastructure and operating procedures. Further work will be necessary to satisfy permitting iv requirements and verify that the reaction product stream is non-hazardous in light of limited toxicity data.

Per- och polyfluoroalkylämnen (PFAS) är i enkla termer fluorerade kolväten som har använts i ett flertal produkter på grund av deras unika förmåga att vara vatten- och smutsavstötande, värmetåliga samt skiktbildande. PFAS har släppts ut i naturen på flera olika sätt. En stor bov till det är brandskum beståendes av vattenhaltigt filmbildande skum (AFFF), vilket innehåller PFAS. Stora volymer brandskum har släppts ut vid bränder eller brandövningsplatser. PFAS är mycket svårnedbrytbara och bioackumulerande, vilket betyder att de stannar kvar i miljön lång tid framöver. Eftersom de även har bevisats vara hälsofarliga vid små mycket mängder, har många varianter av PFAS blivit bannlysta, samt att rening av PFAS blivit centralt. Det har gjorts väldigt mycket forskning kring hur man renar PFAS från vatten vid dricksvattenproduktion, men inte lika mycket på hur man sanerar PFAS från mark och grundvatten in situ (på plats), främst eftersom det är svårt på grund av PFAS-kemikaliernas egenskaper. Det är en viktig del för att kunna ta bort PFAS ur naturen, då en stor del av den PFAS som blivit utsläppt, vid exempelvis brandövningsplatser, skapat plymer i jord och grundvatten som fortsätter vara spridningspunkter. Syftet med litteraturstudien är att sammanställa och jämföra utvecklande metoder inom området in situ sanering av PFAS för att se vilka metoder som har potential att stoppa spridningen. / Per- and polyfluoroalkyl substances (PFAS) are, in simple terms, fluorinated hydrocarbons that have been used in many products because of their unique ability to be water- and dirt-repellent, heat-resistant, and film forming. PFAS has been released into the environment in several ways. A major culprit is firefighting foam consisting of aqueous film-forming foam (AFFF), which contains PFAS. Large volumes of firefighting foam have been released during fires or firefighting exercises. PFAS are very persistent and bioaccumulative, meaning they stay in the environment for a long time. Since they have also been proven to be harmful to health at very low concentrations, several varieties of PFAS have been banned, and cleaning up PFAS has become a central issue. There has been a lot of research on how to clean PFAS from water during drinking water production, but not as much on how to remediate PFAS from soil and groundwater in situ (on-site), mainly because it is difficult due to the properties of the PFAS chemicals. This is an important part of removing PFAS from the environment since a large part of the PFAS that has been released, for example at firefighting sites, has created plumes in soil and groundwater that continue to be points of spread. The purpose of the literature study is to compile and compare developing methods in the field of in situ remediation of PFAS to see which methods have the potential to stop the spread.