Four-Dimensional Modeling of Two Ternary Columnar Composite Compounds

Two ternary columnar composite crystals, Ba15Zr14Se42 and Sr21Ti19Se57, have been characterized and modeled three-dimensionally [1] and they are stated to have a commensurate crystal structure similar to several incommensurate ternary sulfur compounds [2]–[6]. To evaluate whether the two columnar compounds are isostructural to the sulfur compounds they need to be modelled four-dimensionally.Two composite selenium compounds have been studied and compared to similar sulfur compounds to investigate if they possess the same crystal structure

Precipitating Amine Absorption Systems for Carbon Capture

Carbon capture using amine-based absorption is an established technology for the separation of gaseous CO2. It is used in the upgrading of gaseous fuels, and it has also been suggested that it could play a crucial role in the mitigation of climate change through post-combustion carbon capture and sequestration (CCS), and by creating carbon sinks through bioenergy CCS. One drawback of the existing technology is the high energy requirement associated with the regeneration of conventional aqueous amine solutions, which must be addressed in order to make amine absorption a viable option for carbon capture in the industrial sector.The work presented in this thesis focuses on amine solutions where a sterically hindered primary amine (AMP) was studied in mixtures with organic solvents as possible alternatives to conventional aqueous amine solutions. The reason for replacing the water component is the potential reduction in temperature and energy requirement in the regeneration step. The solubility of CO2 and heat of absorption were studied using reaction calorimetry, the chemical species in solution were characterized using nuclear magnetic resonance, and the absorption rate was studied using a wetted wall column.The results showed that AMP in non-aqueous solutions with NMP or DMSO can be regenerated at lower temperatures (<90 °C) than with conventional aqueous amine solutions (≥120 °C). During absorption, precipitation of the AMP carbamate allowed more CO2 to be absorbed in the solution, and precipitation was promoted by increasing the AMP concentration. However, precipitation resulted in a higher heat of absorption than for non-precipitating solutions, which adds to the overall cooling demand of the capture process. When absorption was performed at 40 °C, a CO2 partial pressure of 20 kPa was needed to obtain a similar cyclic capacity to that in 30 wt% MEA, indicating that the studied non-aqueous AMP solutions were suitable for biogas upgrading and industrial carbon capture applications. The less toxic properties of DMSO, and the overall slightly higher solubility of CO2 in AMP/DMSO than in AMP/NMP, suggest that further studies should be carried out using 25 wt% AMP in DMSO.The influence of water accumulation in AMP/DMSO was also studied, due to the hygroscopic properties of DMSO. It was found that the formation of bicarbonate increased with increasing water content. However, some water accumulation may not be problematic as the capacity of the absorption solutions was not reduced in the temperature range studied (40-88 °C) in solutions with a water:AMP molar ratio of 2:1. Preliminary results also indicated that water accumulation could lead to higher AMP degradation rates, but further studies are required to investigate this

Calibration measurements in a catalysis reaction chamber using thermographic phosphors

Accurate temperature measurements using thermocouples inside a catalysis reaction chamber is problematic due to the difficulties to attach the thermocouple to the catalysis sample. It is also of interest to accurately know the pressure inside the reaction chamber. In this work, thermographic phosphors have been utilized in order to determine the temperatures occurring inside a catalysis reaction chamber for typical catalysis measurement environments, and a pressure calibration has been performed. The phosphor was coated on top of the sample holder inside the reaction chamber and on phantom samples imitating real catalytic samples. The results show that the measured temperatures are higher at all locations on the sample holder compared to the temperature readings of the thermocouple, and that the heat transfer to the phantom samples can be said to be fairly efficient. The results also shows that the pressure inside the chamber changes quadratically with a change in flow through the chamber.Kanelbulle och katalysator: Temperaturerna som förändrar världen Temperatur är något som de flesta av oss talar om dagligen. Det må handla om vädrets föränderlighet eller värmepannans oförmåga att värma upp huset; oavsett vad så är temperatur en faktor som diskuteras. För en katalysator i en kemisk omvandling är korrekt temperatur avgörande, och kan spela stor roll för framtidens utvecklingar inom såväl industri som samhället i stort. Föreställ dig en fredag eftermiddag i köket då jobbet precis har blivit färdigt för dagen. Det är dags för fredagsmys och du är sugen på en löjligt god kanelbulle, helt i enlighet med den som Per Morberg tillagade igår kväll i "Vad blir det för mat?". Det första du gör är att sätta på ugnen på rätt temperatur enligt receptet, men så slås du av en tanke. Hur kan man vara säker på att temperaturen i ugnen faktiskt är den som vredet utanpå visar? Om temperaturen inte är korrekt kommer den löjligt goda kanelbullen att bli förstörd och oaptitlig, och en förstörd och oaptitlig bulle är inte det man är sugen på en fredagskväll. Att använda en katalysator i en kemisk omvanlding kan på sätt och vis liknas vid att baka kanelbullar. En katalysator är ett ämne som påskyndar en omvandling mellan andra ämnen till ett nytt ämne, liksom jästen i bulldegen. Allt vetemjöl, socker och kanel skulle inte kunna bli den där goda bullen lika enkelt om jästen inte fanns där och snabbade på bakningen genom att göra degen luftig. För liksom jästen i brödet så är en katalysator i en kemisk process helt beroende av vilka temperaturer som används, och det nya ämnet kan inte bildas lika snabbt och effektivt utan katalysatorn. Om temperaturen är fel kommer därför det nya ämnet antingen att inte skapas alls, eller i mindre utsträckning än vad det hade kunnat göra. Katalysatorer används idag i någon form i ungefär 90\% av alla kemiska produkter som produceras och det är därför viktigt att ha god kunskap om de processer som en katalysator kan sätta igång. Eftersom en katalysator börjar skapa det nya ämnet först vid en given temperatur så är det viktigt att veta vilken temperatur som råder där man vill att den kemiska processen skall äga rum. Detta kan man göra genom att studera ljus från vissa material kallade termografiska fosforer, vilka skickar ut ljus som beror av materialets egen temperatur. Genom att i förväg veta vilket sorts ljus som skickas ut vid en specifik temperatur kan man på så sätt bestämma temperaturen i katalysatorns omgivning, den så kallade mätkammaren. I detta arbete har det visat sig att temperaturen i mätkammaren är högre än vad man tidigare trott, och att den dessutom varierar beroende på var i mätkammaren som mätningarna utförts. Detta innebär att det nu är möjligt att vara mer säker på vilka temperaturer som faktiskt råder i mätkammaren, och att det spelar stor roll var i kammaren som man placerar katalysatorn och ämnena som ska omvandlas. I förlängningen kommer det därför att innebära att mätningarna kan genomföras snabbare utan att man behöver undra vilken temperatur det är i mätkammaren, samt att nya katalysatorer kan utvecklas och undersökas med större precision. Precis liksom att du får löjligt goda kanelbullar en fredagkväll, kommer världen att få fler och bättre kemiska produkter att använda i alla delar av samhället. Allt tack vare att någon kollade vilka temperaturer som egentligen fanns där man verkligen behövde veta det

Some aspects on strength properties in paper composed of different pulps

Abstract For paper producers, an understanding of the development of strength properties in the paper is of uttermost importance. Strong papers are important operators both in the traditional paper industry as well as in new fields of application, such as fibre-based packaging and light-weight building material. In this study, two approaches of enhancing paper strength, reinforcement and multilayering, were addressed. In specific, the effects of adding abaca (Musa Textilis) as a reinforcement fibre for softwood pulp were investigated. Moreover, a handsheet former for the production of stratified sheets, the LB Multilayer Handsheet Former, was evaluated. The LB Multilayer Handsheet Former was then used to study the effects of placing selected fibres in separate layers, rather than by making homogeneous sheets from a mixture of the pulps. Handsheets of a softwood sulphate pulp with the addition of abaca fibres were made in a conventional sheet former. It was seen that the addition of abaca fibres increased the tearing resistance, fracture toughness, folding endurance and air permeance. Tensile strength, tensile stiffness and tensile energy absorption, however, decreased somewhat. Still it was possible to add up to about 60% abaca without any great loss in tensile strength. As an example, with the addition of 30% abaca, the tear index was increased by 36%, while the tensile index was decreased by 8%. It was shown that the LB Multilayer Handsheet Former is suitable for studying the effects of stratification of paper. The sheet former produces sheets with good formation and the uniformity of the sheets, evaluated as the variation of paper properties, is retained at a fairly constant level when the number of layers in the stratified sheets is increased. The uniformity of the sheets produced in the LB Multilayer Handsheet Former are generally at the same level as of those produced in conventional sheet formers. Homogeneous and stratified sheets were produced in the LB Multilayer Handsheet Former and it was found that by stratifying a sheet, so that a pulp with a high tear index and a pulp with a high tensile index are placed in separate layers, it was possible to increase the tear index by approximately 25%, while the tensile index was decreased by 10-20%. i

Environmental effects of coffee, tea and cocoa- data collection for a consumer guide for plant-based foods

In 2020, WWF launched a consumer guide on plant-based products targeting Swedish consumers. The development of the guide is described in a journal paper (Karlsson Potter & Röös, 2021) and the environmental impact of different plant based foods was published in a report (Karlsson Potter, Lundmark, & Röös, 2020). This report was prepared for WWF Sweden to provide scientific background information for complementing the consumer guide with information on coffee, tea and cocoa. This report includes quantitative estimations for several environmental categories (climate, land use, biodiversity and water use) of coffee (per L), tea (per L) and cocoa powder (per kg), building on the previously established methodology for the consumer guide. In addition, scenarios of consumption of coffee, tea and cocoa drink with milk/plant-based drinks and waste at household level, are presented. Tea, coffee and cacao beans have a lot in common. They are tropical perennial crops traditionally grown in the shade among other species, i.e. in agroforestry systems. Today, the production in intensive monocultures has negative impact on biodiversity. Re-introducing agroforestry practices may be part of the solution to improve biodiversity in these landscapes. Climate change will likely, due to changes in temperature, extreme weather events and increases in pests and disease, alter the areas where these crops can be grown in the future. A relatively high ratio of the global land used for coffee, tea and cocoa is certified according to sustainability standards, compared to other crops. Although research on the implications of voluntary standards on different outcomes is inconclusive, the literature supports that certifications have a role in incentivizing more sustainable farming. Coffee, tea and cocoa all contain caffeine and have a high content of bioactive compounds such as antioxidants, and they have all been associated with positive health outcomes. While there is a strong coffee culture in Sweden and coffee contributes substantially to the environmental impact of our diet, tea is a less consumed beverage. Cocoa powder is consumed as a beverage, but substantial amounts of our cocoa consumption is in the form of chocolate. Roasted ground coffee on the Swedish market had a climate impact of 4.0 kg CO2e per kg powder, while the climate impact of instant coffee powder was 11.5 kg CO2e per kg. Per litre, including the energy use for making the coffee, the total climate impact was estimated to 0.25 kg CO2e per L brewed coffee and 0.16 kg CO2e per L for instant coffee. Less green coffee beans are needed to produce the same amount of ready to drink coffee from instant coffee than from brewed coffee. Tea had a climate impact of approximately 6.3 kg CO2 e per kg dry leaves corresponding to an impact of 0.064 CO2e per L ready to drink tea. In the assessment of climate impact per cup, tea had the lowest impact with 0.013 kg CO2e, followed by black instant coffee (0.024 kg CO2e), black coffee (0.038 kg CO2e), and cocoa drink made with milk (0.33 kg CO2e). The climate impact of 1kg cocoa powder on the Swedish market was estimated to 2.8 kg CO2e. Adding milk to coffee or tea increases the climate impact substantially. The literature describes a high proportion of the total climate impact of coffee from the consumer stage due to the electricity used by the coffee machine. However, with the Nordic low-carbon energy mix, the brewing and heating of water and milk contributes to only a minor part of the climate impact of coffee. As in previous research, coffee also had a higher land use, water use and biodiversity impact than tea per L beverage. Another factor of interest at the consumer stage is the waste of prepared coffee. Waste of prepared coffee contributes to climate impact through the additional production costs and electricity for preparation, even though the latter was small in our calculations. The waste of coffee and tea at Summary household level is extensive and measures to reduce the amount of wasted coffee and tea could reduce the environmental impact of Swedish hot drink consumption. For the final evaluation of coffee and tea for the consumer guide, the boundary for the fruit and vegetable group was used. The functional unit for coffee and tea was 1 L prepared beverage without any added milk or sweetener. In the guide, the final evaluation of conventionally grown coffee is that it is ‘yellow’ (‘Consume sometimes’), and for organic produce, ‘light green’ (‘Please consume). The evaluation of conventionally grown tea is that it is ‘light green’, and for organic produce, ‘dark green’ (‘Preferably consume this’). For cocoa, the functional unit is 1 kg of cocoa powder and the boundary was taken from the protein group. The final evaluation of conventionally grown cocoa is that it is ‘orange’ (‘Be careful’), and for organically produced cocoa, ‘light green’

Lung Cell Toxicity of Metal-Containing Nanoparticles

Among the various nanomaterials present in society, many contain metals or metal compounds [...

Multi-criteria evaluation of plant-based foods -use of environmental footprint and LCA data for consumer guidance

Many consumers are willing to move to a more plant-based diet, as is apparent from the increasing demand for plant-based protein sources on many markets. There is scientific evidence that such diets are associated with lower environmental impacts, especially climate impact, land use, and energy use. However, all food production affects the environment, and there is scope for more sustainable food choices even among plant-based foods. We present a method for environmental multi-criteria evaluation of plant-based products to enable communication through a consumer guide, which was developed in cooperation with World Wide Fund for Nature (WWF) Sweden and involves a real-life case of implementation. The guide included 90 products, divided into five product groups. Four environmental impact categories were evaluated (climate impact, biodiversity impact, water use, pesticide use), to give a fuller, more complex picture of potential environmental impacts of plant-based products than when evaluating only one impact category, such as climate impact. Available environmental footprint data and LCA data adapted for the specific consumer market (Sweden) were used. A method for calculating absolute sustainability thresholds for single products was developed, based on newly published global sustainability boundaries for the food system (Willett et al., 2019). To account for the different dietary functions of food, different thresholds for evaluating different food groups were applied, thus accounting for the role, and to some extent the nutrient content, of different food products. This enabled evaluation of foods based on the same grounds, i.e., using the global sustainability boundaries and the same functional unit for all food products (1 kg of food at a store in Sweden), while visualizing differences in environmental impacts of products within a certain food group. This revealed the best choice of protein sources, vegetables, etc. The method provides a way to use large amounts of data of varying quality, and reduces the complexity in evaluating the environmental impacts of food. It therefore hopefully facilitates sustainable plant-based food choices, for more environmentally sustainable food consumption. (C) 2020 The Author(s). Published by Elsevier Ltd

The evolutionary trajectory of the mating-type (mat) genes in Neurospora relates to reproductive behavior of taxa

<p>Abstract</p> <p>Background</p> <p>Comparative sequencing studies among a wide range of taxonomic groups, including fungi, have led to the discovery that reproductive genes evolve more rapidly than other genes. However, for fungal reproductive genes the question has remained whether the rapid evolution is a result of stochastic or deterministic processes. The mating-type (<it>mat</it>) genes constitute the master regulators of sexual reproduction in filamentous ascomycetes and here we present a study of the molecular evolution of the four <it>mat</it>-genes (<it>mat a-1</it>, <it>mat A-1</it>, <it>mat A-2 </it>and <it>mat A-3</it>) of 20 <it>Neurospora </it>taxa.</p> <p>Results</p> <p>We estimated nonsynonymous and synonymous substitution rates of genes to infer their evolutionary rate, and confirmed that the <it>mat</it>-genes evolve rapidly. Furthermore, the evolutionary trajectories are related to the reproductive modes of the taxa; likelihood methods revealed that positive selection acting on specific codons drives the diversity in heterothallic taxa, while among homothallic taxa the rapid evolution is due to a lack of selective constraint. The latter finding is supported by presence of stop codons and frame shift mutations disrupting the open reading frames of <it>mat a-1</it>, <it>mat A-2 </it>and <it>mat A-3 </it>in homothallic taxa. Lower selective constraints of <it>mat</it>-genes was found among homothallic than heterothallic taxa, and comparisons with non-reproductive genes argue that this disparity is not a nonspecific, genome-wide phenomenon.</p> <p>Conclusion</p> <p>Our data show that the <it>mat</it>-genes evolve rapidly in <it>Neurospora</it>. The rapid divergence is due to either adaptive evolution or lack of selective constraints, depending on the reproductive mode of the taxa. This is the first instance of positive selection acting on reproductive genes in the fungal kingdom, and illustrates how the evolutionary trajectory of reproductive genes can change after a switch in reproductive behaviour of an organism.</p

The use of gloves in animal care, in theory and practice : a survey

Syftet med arbetet var att granska hur följsamheten till handskanvändning såg ut på smådjursverksamheter i Sverige, samt undersöka om det fanns ett glapp mellan teori och praktik. Under djursjukskötarprogrammet vid Sveriges Lantbruksuniversitet får studenterna lära sig att handskar ska användas vid många olika typer av arbetsuppgifter, men när kunskaperna från utbildningen sedan ska appliceras i verkligheten kan problem uppstå. En kortare litteraturstudie gjordes där rekommendationer för handskanvändning samt för- och nackdelar med handskar undersöktes. En enkätundersökning gjordes sedan för att undersöka djurhälsopersonalens attityd kring handskanvändning. Denna enkät skickades ut till 60 olika smådjursverksamheter runt om i landet. Det är viktigt att använda handskar på ett korrekt sätt för att risken för smittspridning ska minska. God handhygien uppnås inte genom att endast sätta på sig ett par handskar. I dagsläget finns ett flertal olika typer av handskar på marknaden och att veta vilken typ av handske som ska användas när kan vara svårt. Resultatet av enkäten visade att medvetenhet om korrekt handskanvändning finns, men följsamheten är bristfällig. Respondenterna använde inte handskar vid ett flertal arbetsuppgifter där det enligt rekommendationer bör användas. Anledningen till detta trodde majoriteten av respondenterna var ovana eller dålig rutin. En möjlig lösning till att öka följsamheten av handskanvändning trodde respondenterna var mer utbildning. Exempel på arbetsuppgifter där handskar inte användes i den utsträckning som rekommenderas var bland annat kanylläggning och blodprovstagning samt hantering av dropp. Vid hantering av dropp var det flest djurvårdare som angav att de inte använde handskar. Enligt lag får djurvårdare inte koppla på dropp utan endast koppla av, vad de syftade på med hantering av dropp är inte specificerat. Handskar bör dock användas vid all hantering eftersom risk för kontamination finns vid både på- och avkoppling av dropp. Genomgång av rutiner på arbetsplatsen skulle kunna förbättra följsamheten till detta. Anledningen till att handskar inte användes vid blodprovstagning eller kanylläggning var, enligt kommentarer från respondenterna, på grund av att handskar inte gav samma känsla av kontroll samt att fingertoppskänslan förlorades. Ett större utbud av handskar, samt mer anpassade handskar för djursjukvård kan vara en lösning till detta problem. Resultatet av detta arbete visar att det existerar ett glapp mellan teori och praktik när det kommer till användandet av handskar. Åtgärder måste därför göras för att studenternas kunskaper på ett bra sätt ska kunna införlivas på deras framtida arbetsplatser. Ett förslag kan vara att studenter och handledare (tillika studenternas framtida kollegor) redan under djursjukskötarnas verksamhetsförlagda utbildning försöker skapa en god relation. Detta skulle göra det lättare för de nyexaminerade djursjukskötarna att våga ta plats när de sedan kommer ut i arbetslivet.The aim of this thesis was to investigate how the compliance of using gloves looked like at small animal practices in Sweden and if there was a theory-practice gap. Students at the Veterinary Nursing – Bachelor’s programme at the Swedish Agricultural University are taught that gloves must be used in several kinds of work but once the knowledge acquired from the training will be applied in reality, problems may occur. A short literature study was done where recommendations for glove- and the advantages and disadvantages of gloves examined. A questionnaire was then made to see the animal health care personnel’s attitude about the glove use. The questionnaire was sent to 60 small animal veterinary practices. It is important that gloves are used correctly to reduce the risk of contamination. Good hand hygiene is not obtained by simply putting on a pair of gloves. There are currently many different types of gloves on the market and knowing what type of glove to use when can be difficult. The results of the survey showed that awareness of correct use of gloves exist, but compliance is low. The respondents did not use gloves when recommended in several work duties. The majority of the respondents thought the reason to this was bad habit and a lack of routine. A possible solution to increase the adherence of the glove using, respondents thought were more training. Example of tasks where gloves were not used to the extent that was recommended were catheter placements, blood sampling and handling of the drip. When handling the drip, animal nurse assistants indicated that they did not use gloves. By law, animal nurse assistants are not allowed to connect the drip, only disconnect, what they are referring to in the survey is not specified. Gloves should be used during all handling of the drip since risk for contamination can occur during the whole process. Going through the routines at the workplace could improve adherence to this. According to the respondents comments, not using gloves when handling needles and taking blood samples, was because the gloves did not give the same sense of control. A larger selection of gloves, as well as customized gloves for veterinary care can be a solution to this problem. The results of this thesis shows that there exists a gap between theory and practice when it comes to using gloves. Measures must therefore be made to incorporate the students’ knowledge into their future workplace. One suggestion might be to create good relationship between student and tutors (who is also the students’ future colleagues) during the work-based education. This would make it easier for newly graduated animal nurses to dare take place when they come into work