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Data regarding diabetic foot ulcers in patients after solid organ transplantation, particularly kidney transplantation, are limited. Chronic immunosuppression may be associated with impaired wound healing and a higher risk of amputations. In this study, we characterised the clinical presentation and outcomes of patients after kidney transplantation admitted to the diabetic foot unit, compared to non-kidney-transplant patients.Data on the baseline characteristics, clinical presentation, and outcomes of all patients admitted to the diabetic foot unit of a large tertiary centre between the years 2014 and 2019 were collected. The most recent admission of each patient was considered. Primary outcomes were major amputations and 1 year mortality rate.During the study period, 537 patients were hospitalised, 18 of them were receiving immunosuppressive therapy due to kidney transplantation. Baseline characteristics of the patients were broadly similar, except that smoking was reported by 22.0% of the non-transplant patients and by none of the post-transplant patients (p = 0.01). Post-transplant patients tended to be younger (59.4 ± 11.1 vs. 65.3 ± 12.2; p = 0.07), were more likely to have type-1 diabetes (16.7% vs. 5.2%; p = 0.07) and had lower glucose levels upon admission (9.4 ± 4.3 vs. 12.0 ± 6.4 mmol/L; p = 0.07). Overall, 30% of the patients underwent major amputation, in-patient mortality rate was 9.3%, and 1 year mortality rate was 27.2%. Rates were similar in the post-transplant versus the non-post-transplant patients (p = 0.83, 1.00, 0.59, respectively).Post-transplant patients did not incur worse outcomes in spite of immunosuppressive therapy. Limb salvage efforts should be pursued in these patients similar to the overall population.

Thermoplastic, polysaccharide-based plastics are environmentally friendly. However, typical shortcomings include lack of water resistance and poor mechanical properties. Nanocomposite manufacturing using pure, highly linear, polysaccharides can overcome such limitations. Cast nanocomposites were fabricated with plant engineered pure amylose (AM), produced in bulk quantity in transgenic barley grain, and cellulose nanofibers (CNF), extracted from agrowaste sugar beet pulp. Morphology, crystallinity, chemical heterogeneity, mechanics, dynamic mechanical, gas and water permeability, and contact angle of the films were investigated. Blending CNF into the AM matrix significantly enhanced the crystallinity, mechanical properties and permeability, whereas glycerol increased elongation at break, mainly by plasticizing the AM. There was significant phase separation between AM and CNF. Dynamic plasticizing and anti-plasticizing effects of both CNF and glycerol were demonstrated by NMR demonstrating high molecular order, but also non-crystalline, and evenly distributed 20 nm-sized glycerol domains. This study demonstrates a new lead in functional polysaccharide-based bioplastic systems.

The objective of this study was to investigate the factors influencing Israeli teachers who participated in the national ‘Laptop for Every Teacher’ program (LET) three-year technology integration program. We assert that although there are several variables influencing the success of such an extensive ICT integration program as the LET program, school management attitude is crucial, and a key factor for the program’s success. The results of the analysis indicate that the variance in attitudes toward technology use is explained by support from management, technology use before the training, and seniority in teaching. Two main conclusions are drawn: A top–down initiative forcing the school administration to participate in a long-term process aiming at changing the school’s culture cannot succeed without engaging the principals into the program and advancing them to technological leaders. Additionally, without the schools’ administration support, teachers are more likely to continue teaching in the method with which they are most familiar.

Thermoplastic, polysaccharide-based plastics are environmentally friendly. However, typical shortcomings include lack of water resistance and poor mechanical properties. Nanocomposite manufacturing using pure, highly linear, polysaccharides can overcome such limitations. Cast nanocomposites were fabricated with plant engineered pure amylose (AM), produced in bulk quantity in transgenic barley grain, and cellulose nanofibers (CNF), extracted from agrowaste sugar beet pulp. Morphology, crystallinity, chemical heterogeneity, mechanics, dynamic mechanical, gas and water permeability, and contact angle of the films were investigated. Blending CNF into the AM matrix significantly enhanced the crystallinity, mechanical properties and permeability, whereas glycerol increased elongation at break, mainly by plasticizing the AM. There was significant phase separation between AM and CNF. Dynamic plasticizing and anti-plasticizing effects of both CNF and glycerol were demonstrated by NMR demonstrating high molecular order, but also non-crystalline, and evenly distributed 20 nm-sized glycerol domains. This study demonstrates a new lead in functional polysaccharide-based bioplastic systems.

Covering: Up to 2019Phenolic cross-links and phenolic inter-unit linkages result from the oxidative coupling of two hydroxycinnamates or two molecules of tyrosine. Free dimers of hydroxycinnamates, lignans, play important roles in plant defence. Cross-linking of bound phenolics in the plant cell wall affects cell expansion, wall strength, digestibility, degradability, and pathogen resistance. Cross-links mediated by phenolic substituents are particularly important as they confer strength to the wall via the formation of new covalent bonds, and by excluding water from it. Four biopolymer classes are known to be involved in the formation of phenolic cross-links: lignins, extensins, glucuronoarabinoxylans, and side-chains of rhamnogalacturonan-I. Lignins and extensins are ubiquitous in streptophytes whereas aromatic substituents on xylan and pectic side-chains are commonly assumed to be particular features of Poales sensu lato and core Caryophyllales, respectively. Cross-linking of phenolic moieties proceeds via radical formation, is catalyzed by peroxidases and laccases, and involves monolignols, tyrosine in extensins, and ferulate esters on xylan and pectin. Ferulate substituents, on xylan in particular, are thought to be nucleation points for lignin polymerization and are, therefore, of paramount importance to wall architecture in grasses and for the development of technology for wall disassembly, e.g. for the use of grass biomass for production of 2nd generation biofuels. This review summarizes current knowledge on the intra- and extracellular acylation of polysaccharides, and inter- and intra-molecular cross-linking of different constituents. Enzyme mediated lignan in vitro synthesis for pharmaceutical uses are covered as are industrial exploitation of mutant and transgenic approaches to control cell wall cross-linking.

Corn bran is a major agro-industrial byproduct from corn starch processing. The bran is particularly rich in highly substituted feruloylated glucuronoarabinoxylan (FGAX). Yet, due to its recalcitrance to biocatalytic degradation, corn bran FGAX is currently not utilized in biorefinery processes. Here, we report selective enzymatic extraction of both single, and double-stranded high-molecular-weight FGAX molecules from corn bran using a bacterial, glucuronoyl-specific glycoside hydrolase family 30 endo-1,4-β-xylanase (EC 3.2.1.8) from Dickeya chrysanthemi (DcXyn30). The enzymatic extraction using DcXyn30 was optimized with respect to temperature, pH, and time to maximize yields of high-molecular-weight polysaccharides. Examination of the enzymatically extracted FGAX using SEC, HPAEC, LC-MS, and NMR analysis (after acid or alkaline hydrolysis) revealed that both single-stranded and double-stranded FGAX were extracted, since diferulate-linkages were present in the extracted FGAX. Furthermore, the NMR-analysis indicated presence of 1,5-linked arabinan dimers suggesting that some of the xylopyranosyl residues in the extracted FGAX contained arabinofuranosyl-arabinofuranosyl substitutions in addition to a significant amount of classical doubly-arabinose substitutions. Laccase treatment of the extracted FGAX produced strong hydrogels via oxidative, covalent feruloyl-cross-linking. At pH 6.5 the Myceliophthora thermophila derived laccase produced significantly faster cross-linking kinetics than the laccase from Pleurotus ostreatus as measured rheologically. The data reveal novel insight into corn bran FGAX chemistry and provide a new direction for enzyme-assisted upgrading of corn bran for valuable functional hydrogel applications.

Photobiocatalysis holds great promise toward the development of sustainable and environmentally friendly processes, harnessing light to drive biocatalytic reactions. However, photobiocatalysis at the interface of insoluble substrates, such as cellulose, has not been studied in much detail. In this context, the catalytic enhancement of lytic polysaccharide monooxygenases (LPMOs) by light is of great interest to the biorefinery field due to their capacity to oxidatively cleave such recalcitrant polysaccharides which can facilitate the degradation of lignocellulose. It has previously been reported that light-driven LPMO reactions have a huge catalytic potential, but effective continuous illumination in reactors may be challenging. Therefore, we investigated the impact of intermittent illumination. We show that illumination intervals as short as 1 s/min enable LPMO catalysis on phosphoric acid-swollen cellulose (PASC) to the same level as continuous illumination. Additionally, time-resolved measurements indicate that reductant depletion, and not enzyme inactivation, limits light-driven LPMO reactions. This study shows that a 60-fold reduction in illumination time enhances LPMO catalysis while protecting reaction elements, e.g. the reductant. Most importantly, the significant enhancement of LPMO catalysis with minimal and intermittent illumination is promising toward an application of photobiocatalytic depolymerization of lignocellulose where shading and light scattering minimize light availability and continuity., SCOPUS: ar.j, info:eu-repo/semantics/published

BACKGROUND: Crosslinked enzyme aggregates (CLEA) technology is a rapid and versatile method to produce immobilized enzymes via precipitation and cross-linking. A direct relationship between CLEA final activity and process parameters is however yet to be clarified. To address the issue, we have used a factorial design to test the formation and optimization of CLEA made from technical grade cellulase (EC 3.2.1.4). Three types of precipitant (ammonium sulfate, polyethylene glycol, tert-butyl alcohol) were used at varied levels of cross-linker concentration, cross-linking time, and temperature. RESULTS: It was found that the CLEAs produced with tert-butyl alcohol were inactive, whereas the polyethylene glycol- and ammonium sulfate-CLEA, recovered 29 and 17% of the free enzyme activity, respectively. Testing for re-usability, we observed that the polyethylene glycol-CLEA maintained 40% of the initial activity after four cycles, in contrast the ammonium sulfate-CLEA only maintained 10% of its activity after one cycle. CONCLUSION: Our study highlights the importance of evaluating the effect of the precipitant on final CLEA activity rather than re-solubilized enzyme activity. It was demonstrated that polyethylene glycol, despite not being able to precipitate the enzymes as readily as ammonium sulfate, resulted in better performing CLEA. (Less)

Cellulose fibers can be freed from the cell-wall skeleton via high-shear homogenization, to produce cellulose nanofibers (CNF) that can be used, for example, as the reinforcing phase in composite materials. Nanofiber production from agro-industrial byproducts normally involves harsh chemical-pretreatments and high temperatures to remove noncellulosic polysaccharides (20-70% of dry weight). However, this is expensive for large-scale processing and environmentally damaging. An enzyme-only pretreatment to obtain CNF from agro-industrial byproducts (potato and sugar beet) was developed with targeted commercial enzyme mixtures. It is hypothesized that cellulose can be isolated from the biomass, using enzymes only, due to the low lignin content, facilitating greater liberation of CNF via high-shear homogenization. Comprehensive Microarray Polymer Profiling (CoMPP) measured remaining extractable polysaccharides, showing that the enzyme-pretreatment was more successful at removing noncellulosic polysaccharides than alkaline- or acid-hydrolysis alone. While effective alone, the effect of the enzyme-pretreatment was bolstered via combination with a mild high-pH pretreatment. Dynamic rheology was used to estimate the proportion of CNF in resultant suspensions. Enzyme-pretreated suspensions showed 4-fold and 10-fold increases in the storage modulus for potato and sugar beet, respectively, compared to untreated samples. A greener yet facile method for producing CNF from vegetable waste is presented here.

The building sector give rise to one fifth of the Swedish greenhouse gas emissions. This sector needs a climate shift to reach the UN Sustainable Development Goals. Local municipalities play an important role in this shift and the City of Gothenburg has therefore initiated an innovation project, Hoppet - the first fossil-free preschool. The purpose is to highlight the climate issue and inspire the industry to develop new fossil-free products and processes as well as promoting existing ones. Hoppet is an initiative leading the way towards a fossil-free society in Gothenburg City, Sweden and the world. Hoppet will be built with minimal climate impact and no fossil resources, as far as possible. This includes everything from production and transport of materials to energy used in the building. The fossil content and climate impact of traditionally built preschools have been calculated as a benchmark for Hoppet. More than 70 % of the 250 building products in a traditionally built preschool has a petroleum-based content, eg plastics. The climate impact of the building products in a traditionally built preschool was calculated to about 390 kg CO2-eq./m2 gross area. The design phase of first Hoppet preschool started in the autumn 2019 and, before materials are chosen, calculations of the actual climate impact are made. Examples of climate calculations and strategies for material selection for Hoppet are presented as well as ongoing and future work for fossil-free construction. For more than two years, the project has scouted for new innovative materials and old techniques in order to build fossil-free. Finding fossil-free and climate neutral products has been challenging. Product development and innovation are key issues for fossil-free construction, as well as communication and collaboration within the construction industry. Five important strategies for the transition into a fossil-free society have been identified; biobased building products, reused and recycled building products, minimized material usage, fossil-free construction site and a product life cycle perspective.

Removal of non-cellulosic polymers from vegetable pulp to obtain cellulose nanofibers (CNF) is normally achieved by chemical pre-treatments which requires several washing steps. In the present study, it is demonstrated how incubation of sugar beet pulp at pH 9, followed by treatment with polysaccharide-degrading enzymes and subsequent bleaching can be done in a one-pot procedure to make CNF. The new method consumes 67% less water and removes non-cellulosic polysaccharides with similar efficiency as a chemical method. In addition, CNF produced by the new method contained slightly more pectin and formed gels with 2.7 times higher storage modulus. Nanopapers cast from chemically- and enzymatically produced CNF showed similar mechanical properties. However, without the pH 9 incubation step, the enzymes accessibility to cell-wall polymers was limited resulting in lower gel and paper strengths. In conclusion, the new method offers a sustainable route for producing high quality CNF from sugar beet waste.

The direct and indirect hydro-dynamic loads in the suppression pool of the BWR fleet were developed well before 2000. These loads were based on scaled experiments and numerical solutions using one dimensional models. The analysis was cumbersome and conservatisms were added in multiple steps. As these loads spread throughout the containment, as global vibrations, they are generally a part of all structural verification inside the containment. This fact has made it hard and unpractical to challenge and revise these loads, as a change could lead to significant re-work. A consequence of this is that loads in the suppression pools have seldom been revisited, regardless if they cause local or global vibrations. This is problematic when new equipment is needed. The design of this equipment suffers from the very conservative loads. Experience has shown that these loads can be challenged and refined using updated techniques, leading to significantly lower loads. This was realized during the modernization of Swedish plant Oskarshamn Unit 2 with Mark II containment, where loads following pool swell proved to be particularly challenging and it was decided to investigate possibilities to reduce the conservative loads. Due to the large scale of the condensation pool coupled with the transient and small scaled condensation of steam at the drywell vent pipe nozzle full CFD resolution is not feasible. Instead lumped models in GOTHIC was used to increase resolution from the 1D approach of normal containment analysis, to a resolution that can account for the features of the condensation pool. This showed that the pool swell was less uniform than initially thought, leading to fewer objects affected as well as lower loads on objects that suffered from these loads. A full CFD analysis was then used to resolve phenomena working on even shorter time scales leading to a complete rework of all local loads. The loads addressed using updated codes and modelling techniques was pool swell impact (PSI), pool swell drag (PSD) and local drag loads due to pressure relief valve opening, LV/SRV. The current work shows that using updated modelling techniques and aligning results with previous analysis and documentation, it is possible to reduce loads for some events in the suppression pool without violating safety for the power plant. The results from the GOTHIC model shows that the cylindrical shape of the pool will create an uneven velocity distribution radially at pool swell resulting in much smaller loads at the outer boundary. CFD analysis of the LV/SRV event shows that the loads are reduced in comparison with previous methodology and this is mainly because of shadow effects. The calculations also verifies assumptions used in the previous methodology.

Recently developed organic photovoltaics (OPVs) show distinct advantages over their inorganic counterparts due to their lighter weight, flexible shape, versatile materials synthesis and device fabr ...

Bu makalede, manyetik nano-parçacıkların da içinde bulunduğu, çapraz bağlı enzim topluluklarının (CLEA) oluşturulması ve tekstil işlemede kullanılması fikri ve uygulaması sunulmuştur. CLEA’nın, serbest enzimlere göre daha verimli olmasının iki temel nedeni vardır. Birincisi ayarlanabilen CLEA büyüklüğü ile enzim etkinliğinin kumaşın gözeneklerine girme miktarı sınırlandırılabilir ki bu, kumaşın mukavemetini artırır. İkincisi ise, enzimlerin kumaşın istenmeyen bölümlerine girişini engelleyerek, yalnızca yüzeye yönlendirilmeleri sayesinde yüzey işlenme veriminin arttırılmasıdır. Bunlara ek olarak, CLEA içine yerleştirilmiş manyetik nano-parçacıklar CLEA’nın tekrar tekrar kullanılmasına imkan sunar. Önerilen süreç, alışılagelmiş kimyasal süreçlerle karşılaştırıldığında daha tutumlu ve çevrecidir. İlk CLEA tasarımımız ve uygulamaları, öncül ölçüm sonuçları ile beraber sunulmuştur, In this proceeding, architecting novel magnetic Cross-Linked-Enzyme-Aggregates (CLEA) nanoparticles to effectively and controllably modify textile surfaces without damaging the fabric itself, will be discussed. The efficiency is due to exponentially increased surface concentration of biocatalyst and to the choice of aggregate size which controls the penetration depth and hence preventing the fabric disruption. In addition, due to the presence of magnetic nanoparticles, the continuous recovery and reusability makes this design more economic and ecologic compared to the conventional chemical processes. The careful fabrication and functionalization of such a design with preliminary results will be presented in this contribution.

Residential and commercial buildings give rise to about one fifth of the greenhouse gas emissions in Sweden. One important goal of the City of Gothenburg is to be a climate neutral city with fair emission levels of greenhouse gases in 2030. In order to reach this goal, a demonstration project has been initiated with the aim to build a fossil free preschool - Hoppet. Hoppet will be built with a minimal climate impact and with no fossil resources. This includes everything from production and transport of materials to energy usage in the building. The fossil content and the climate impact of a standard preschool has been calculated, to be used as a benchmark for Hoppet. The result shows that all 250 building products in the reference preschool have a climate impact but finding fossil free and climate neutral alternative products has been found challenging. The climate impact of the building products in the reference preschool is calculated to more than 220 kg CO2-eq. per m2. Strategies to decrease climate impact for Hoppet preschool has been developed. For example, product development and innovation has been identified as key issues as well as increased collaboration between different actors in the construction industry. Communicating the project internationally is of high importance to find partners and innovations that don’t exist in Sweden as well as to engage other stakeholders to help transform the building sector.

Dissolving pulp was depolymerized with 2.5M HCl into cellulose fractions with decreasing molecular weight relative to acid treatment time. The cellulose fractions were dissolved at various concentrations in the ionic liquid 1-ethyl-3-methylimidazolium acetate (EmimAc) with co-solvent DMSO at ratio 1 : 1 (w/w) and electrospun. Size exclusion chromatography was used to evaluate the molecular weight distributions and the rheological properties were characterized with a cone-and-plate rheometer. Scanning electron microscope was used to evaluate the fiber morphology, and thereby spinnability. Zero shear viscosity as a function of cellulose concentration show that all the solutions in this study are in the entangled semi-dilute regime; where the polymer concentration is large enough for significant overlap necessary for chain entanglement. However, within the intervals studied, neither cellulose concentration nor molecular weight seems to be decisive for if a solution can be electrospun into fibers or not. It is rather the viscosity of the solution that is decisive for electrospinnability, even though the solution is in the entangled semi-dilute regime.

The increasing globalization has lead companies to venture into new areas of business, and thereby new markets. When entering a new market, it is important to gain market knowledge to be able to satisfy the customers’ needs. Companies are no longer competing only with products and services; they are also striving to increase their competitive advantage by improving the processes that ultimately deliver the result. In order to obtain competitive advantages, designing business processes to meet the needs of the customers is therefore vital for companies to succeed. Entries into new markets may therefore require adaption to new customers in order to sustain the purpose of the processes. For a telecommunications company venturing into the market of Public Safety, changing preconditions for customers are inevitable, why companies must be aware of changes in the customer’s needs and requirements. When preconditions are changed in this sense, adaptions to the supplier’s sales process might be necessary in order to enable building a relationship between the supplier and the customer. The aim of this study is therefore to establish how companies active in the telecommunications industry can adapt their sales process to new customer requirements and needs when entering the market of Public Safety. This to address the issues that may arise when the established sales process is no longer suited to new customers’ needs and requirements. The thesis is based on a case study at a global telecommunications company, which recently entered the Public Safety market. To create a greater understanding of subjects and findings presented in the report, a literature review touching on the structure of the sales process as well as the preconditions surrounding public procurement is presented. To further create an understanding of the case company’s sales process, nine in-depth interviews were conducted with employees active in the process. In order to draw conclusions on how the sales process should be adapted to Public Safety, five in-depth interviews with customers were conducted. Through analysis, seven underlying needs of the customers could be identified. Further analysis has focused on whether the case company fulfills these needs and aimed to identify gaps between the sales process and the customers’ procurement process. Based on the analysis, recommendations for companies who are entering markets where the customers have similar needs were formulated. One major conclusion of this thesis is that customers within the Public Safety market value traits in a supplier that are not specified as requirements in the formal tender documents. Furthermore, the conclusions expand on these traits and touches on their impact on the customer’s assessment of the supplier. The conclusions also connect the findings of the study to the theory presented, consequently emphasizing how companies should adapt their sales processes to better meet the customer needs. Validerat; 20160629 (global_studentproject_submitter)

Cellulose was electrospun with various concentrations of ionic liquid and cosolvent. Three different cosolvents were used in this study; dimethylacetamide (DMAc), dimethyl formamide (DMF), and dimethyl sulfoxide (DMSO). The cosolvents were added to modify the viscosity, electrical conductivity, and surface tension of the solutions. The solubility of cellulose in ionic liquids is highly affected by changes in solvent properties on the molecular level in the binary solvent systems. The difference in molecular structure of the cosolvents and the interactions between cosolvent and ionic liquid can explain the difference in dissolution power of the cosolvents. Scanning electron microscope (SEM) was used to characterize electrospun cellulose fibers. For the systems tested the importance of having a rather high viscosity and high surface tension, and some degree of shear thinning to produce fibers is shown.

Oats are a new biofuel possible to use in modified residential wood pellet combustion appliances. The emissions of organic compounds from five sequential combustion stages; initial smouldering, early flaming, late flaming, after-flame smouldering and final glowing, for incomplete burning of oats on a laboratory scale were determined by gas chromatography and compared to those of softwood pellets. High concentrations of 1,6-anhydroglucose and furan-related compounds were released from the initial smouldering of oats, while high concentrations of methoxyphenols were released during the initial smouldering of wood pellets. The results indicate that oats are a biofuel with relatively low emissions during combustion, almost as low as those from wood pellets. After-flame smouldering of oats released lower concentrations of methane, alkenes and aromatic hydrocarbons than the after-flame smouldering of wood pellets. The large differences in emissions from the various combustion stages should be considered when evaluating the environmental aspects and health effects of residential burning of oats and wood pellets.

Four handling options for sewage sludge were studied from an environmental system's perspective using life cycle assessment. The studied options were restoration of mining areas, composting with other biomaterials for use on golf courses, hygienisation through storage for agricultural use, and supercritical water oxidation with phosphorus recovery. The results are discussed in terms of impact on global warming, acidification, eutrophication, and the use of finite resources and primary energy. A very large impact of including biogeochemical emissions from sludge handling and spreading on land can be seen. System expansions for replaced artificial fertilizers also had a major influence on the results. It is clear that it is important for the environmental outcome of sludge treatment options that biogeochemical emissions from sludge are minimized and that nutrients and other resources are utilized efficiently.

The purpose of this study is to understand the characteristics of relationship quality within a business-to-business (b2b) setting, and also to understand how these characteristics vary in importance between countries. Replicating an earlier study, conjoint analysis was used to study how a sample of 48 Iranian managers trade off different attributes of relationship quality. Overall, the most important attribute to the sample was profit, followed by trust and power. However, there was significant variance within the sample. When compared with an earlier study of UK managers in which an identical methodology was used, it was found that while profit was important for both groups, it was more so for Iranian managers. Trust was also important in both samples, in line with what was expected from the literature. Power was found to be important for Iranian managers whereas in the UK, power was reported as the least important attribute.

A conjugated polymer was prepd. based on 2-thia-1,3,5,8-tetraaza-cyclopenta[b]naphthalene central electron accepting unit and electron donating thiophene units on each side, LBPP-1, with unusually low band-gap (ca. 1.0 eV). Light absorption and photovoltaic response up to 1200 nm in composites with fullerene were demonstrated. The performance of solar cells contg. LBPP-1 is described and the suitability of LBPP-1 for photodetection in the IR region is discussed.

Combined heat and power (CHP) is a strategy aimed at reducing the impact of the energy sector on the climate by more efficient use of the energy content of the fuel. The implementation of CHP requires the utilisation of the heat produced. Space heating by means of district heating is one possible use for such heat. In countries such as Sweden, where district heating is already extensively used, many multiapartment buildings are connected to district heating. For increased use, the distribution systems will have to expand into suburbs with single family homes. However, the environmental impact and cost of the district heat distribution system increase when the pipe networks are extended into such areas. This is due to the production and installation of longer pipe networks and increased heat losses from the system. Attempts have been made to find new types of pipe constructions in order to lower the costs of connecting single family homes to district heating. These should be evaluated from an environmental perspective. The EPSPEX system is a distribution system intended for suburban areas. This system consists of cross-linked polyethylene (PEX) pipes in insulating blocks of expanded polystyrene (EPS). This paper presents a life cycle assessment of the EPSPEX district heat distribution system. In a second scenario, sub-stations were added. The results indicate areas that require improvement and provide a basis for comparison with other types of district heat distribution systems. Production, network construction and use of the district heat system were studied by means of life cycle methodology, employing specific data for the EPSPEX system and generic data for upstream impacts of the materials used. The system constructed in Vraen, Varnamo, Sweden, in 2002 was studied. The district heating used in Vraen is mainly based on biofuels. The functional unit was the use of one metre of an EPSPEX district heating system over a period of one year. The expected system life was 30 years. The results were characterised as global warming potential, acidification potential, eutrophication potential and the use of finite resources, as well as weighted by EPS 2000, ExternE and EcoIndicator 99. No external review was performed, but a reference group of district heating experts familiar with the practice has reviewed the study. Heat losses are clearly the main environmental impact in all characterisations and weightings (71–92% of the total impact), despite the fact that the heat production studied was mainly based on biomass combustion, generally perceived to be environmentally friendly. Of the system components, the production of EPS insulation blocks had the largest environmental impact. This impact, however, is compensated for by the fact that the need to produce less heat leads to a lower level of emissions. Several characterisation methods revealed that the production and combustion of diesel for excavating the pipe trench has a significant environmental impact. The jointing brass swaged coupling used for the PEX fluid pipes has a surprisingly high impact in terms of acidification and EPS 2000, considering the small amount of brass in the system. The life cycle environmental impact is dominated by the heat production needed to compensate for heat losses from the system, despite the fact that the EPSPEX system is relatively well insulated compared to a conventional district heating system. It is possible to shut down the heating circuit and only use the hot tap water circuit during the summer months; this reduces the heat losses and is an advantageous feature of the system. The second largest environmental impact of the EPSPEX system arises from the production of the EPS insulation blocks. A decrease in nitrogen oxide emissions, especially those caused by the excavation and filling of pipe trenches, would be beneficial. A rough comparison has been made with available literature data for conventional DN25 twin pipes. The results indicate that the environmental impact of the EPSPEX system is probably lower. However, the pipes are not identical, as the water delivery capacity of the conventional pipe is slightly lower. In Sweden, new types of pipes are being developed for district heating in suburban areas, and there is a need for an environmental comparison between such new alternatives and previous results for conventional polyurethane insulated steel pipes. This study reveals that biofuels, although perceived to be environmentally friendly, must be used with caution in order to ensure a satisfactory environmental performance. Heat loss from district heating should be minimized also when biofuels are used. The most immediate way to reduce such environmental impact is to increase the insulation. The environmental trade-off between lower heat losses achieved by the use of more insulation and the production of greater amounts of insulation material should be further studied.

Charge transport in a near infrared absorbing polyfluorene copolymer (APFO-Green1) and its blends with methanofullerene [6,6]-phenyl C61-butyric acid methyl ester (PCBM), and 3′-(3,5-bis-trifluorom ...

Low-bandgap alternating polyfluorenes with different donor-acceptor-donor moieties were synthesized. Electrochem. and optical absorption measurement show that onset bandgaps of these polymers range from 1.2 to 1.5 eV. These polymers, blended with a C70-deriv. as acceptor, are used for solar cell fabrication. Devices show promising photovoltaic properties, and the spectral response of photocurrent covers all visible and near-IR wavelength regions with its onset extended to 1 mm. The best data gives a photocurrent d. of 3.4 mA/cm2, open circuit voltage of 0.58 V and power conversion efficiency of 0.7% under illumination of AM1.5 (1000 W/m2) from a solar simulator. [on SciFinder (R)]

An alternating polyfluorene (APFO) with low band-gap segments. APFO-Green1, was synthesized for use in optoelectronic devices. The low band-gap segment consists of an electron acceptor (A), fenced by electron donors (D). This D-A-D configuration leads to partial charge transfer in the polymer backbone and a low band-gap of 1.3 eV. Characterization of APFO-Green1 include measurement of light absorption and emission at extended wavelengths and high hole mobility was found. Blends of the polymer with different fullerene derivs. exhibit unusually high photovoltaic performance at long wavelengths, making this type of conjugated polymers promising for application in plastic solar cells. [on SciFinder (R)]

Plastic solar cells have been fabricated using a low-bandgap alternating copolymer of fluorene and a donor-acceptor-donor moiety (APFO-Green1), blended with 3'-(3,5-bis-trifluoromethylphenyl)-1'-(4-nitrophenyl)pyrazolino fullerene (BTPF70) as electron acceptor. The polymer shows optical absorption in two wavelength ranges, l < 500 nm and 600 < l < 1000 nm. The BTPF70 absorbs light at l < 700 nm. A broad photocurrent spectral response in the wavelength range 300 < l < 1000 nm is obtained in solar cells. A photocurrent d. of 3.4 mA cm-2, open-circuit voltage of 0.58 V, and power-conversion efficiency of 0.7% are achieved under illumination of AM1.5 (1000 W m-2) from a solar simulator. Synthesis of BTPF70 is presented. Photoluminescence quenching and electrochem. studies are used to discuss photoinduced charge transfer. [on SciFinder (R)]

Two new alternating polyfluorene copolymers containing different low band gap segments have been designed and synthesized for use in optoelectronic devices. The low band gap segments consist of electron donating and accepting moieties which induce a partial charge transfer in the polymer backbone and thereby, a lower band gap. Results obtained from characterization of the new materials, called APFO-Green1 and APFO-Green2, include absorption and emission at extended wavelengths as well as high stability. Furthermore, blends of the new copolymers with different fullerene derivatives exhibit unprecedented photovoltaic behavior at long wavelengths.

Polymer solar cells were fabricated from a low band-gap alternating polyfluorene copolymer, APFO-Green2, combined with [6,6]-phenyl-C61-butyric acid Me ester (PCBM), from org. solns. External quantum efficiencies of the solar cells show an onset at 850 nm and a peak of >10% located at 650 nm, which corresponds to the extended absorption spectrum of the polymer. A photocurrent of 3.0 mA/cm2, photovoltage of 0.78 V, and power conversion efficiency of 0.9% were obtained with solar cells based on this new low-bandgap polymer under an illumination of AM 1.5 (1000 W/m2) from a solar simulator. [on SciFinder (R)]

We report on transistors and light-emitting diodes using a conjugated polymer consisting of alternated segments of fluorene units and low-band gap donor–acceptor–donor (D–A–D) units. The D–A–D segment includes two electron-donating thiophene rings combined with a thiadiazolo-quinoxaline unit, which is electron withdrawing to its nature. The resulting polymer is conjugated and has a band gap of around 1.27 eV. Here we present the corresponding electro- and photoluminescence spectra, which both peak at approximately 1 μm. Single layer light-emitting diodes demonstrated external quantum efficiencies from 0.03% to 0.05%. The polymer was employed as active material in thin film transistors, a field-effect mobility of 3 × 10−3 cm2/V s and current on/off ratio of 104 were achieved at ambient atmosphere.

Two new crescent-shaped unsymmetrical cyanine dyes have been synthesised and their interactions with DNA have been investigated by different spectroscopic methods. These dyes are analogues to a minor groove binding unsymmetrical cyanine dye, BEBO, recently reported by us. In this dye, the structure of the known intercalating cyanine dye BO was extended with a benzothiazole substituent. To investigate how the identity of the extending heterocycle affects the binding to DNA, the new dyes BETO and BOXTO have a benzothiazole group and a benzoxazole moiety, respectively. Whereas BEBO showed a heterogeneous binding to calf thymus DNA, linear and circular dichroism studies of BOXTO indicate a high preference for minor groove binding. BETO also binds in the minor groove to mixed sequence DNA but has a contribution of non-ordered and non-emissive species present. A non-intercalative binding mode of the new dyes, as well as for BEBO, is further supported by electrophoresis unwinding assays. These dyes, having comparable spectral properties as the intercalating cyanine dyes, but bind in the minor groove instead, might be useful complements for staining of DNA. In particular, the benzoxazole substituted dye BOXTO has attractive fluorescence properties with a quantum yield of 0.52 when bound to mixed sequence DNA and a 300-fold increase in fluorescence intensity upon binding.

The amplified spontaneous emission (ASE) of optically pumped films of poly(2-(2′,5′-bis(octyloxy)benzene)-1,4-phenylenevinylene (BOP-PPV) was studied in structures comprising a gate electrode, a thin film of gate insulator material (SiO2) and the polymer film as luminescent semiconducting layer (i.e. a field effect transistor without the source and drain electrodes). The influences of different gate electrodes on the threshold and the wavelength of the amplified emission were measured for variable thickness of the gate insulator. An exponential increase in ASE threshold (It) with decreasing separation between electrode and polymer layer was observed. In structures with 200 nm SiO2 gate insulator, It=300 kW/cm2 with an n-Si gate electrode and 200 kW/cm2 with Au electrode (100 nm thick). Compared to the same polymer film on pure SiO2 (It=2 kW/cm2), this increase results from waveguide losses in the nearby gate electrode. With an indium–tin–oxide (ITO) gate electrode (140 nm thick) on glass, again with a 200...

In this study we report the synthesis, characterization, and photovoltaic properties of a series of six conjugated polymers based on donor-acceptor-donor (DAD) structure. The polymers are obtained via Suzuki polymerization of different alkoxy-substitutedDADmonomers together with a substituted fluorene or phenylene monomer. Application of polymers as light-harvesting and electron-donating materials in solar cells, in conjunction with both [60]PCBMand [70]PCBMas acceptors, show powerconversion efficiencies (PCEs) up to 2.9%, values obtained without extensive optimization work. Furthermore, atomic force microscopy and field-effect transistor (FET) mobility measurements of acceptor-polymer mixtures show that differences in substitution on the polymers affect morphology, mobility, and device performance. Within the series of polymers, all showing similar optical absorption and redox behavior, substituents play an important role in phase separation on a micrometer scale, which in turn has a large impact on device performance. The phase-separation behavior is clearly seen in [70]PCBM devices where the best-performing devices are obtained using the polymers with short alkoxy groups or no substituents together with a high speed of spin coating during device preparation. Refereed/Peer-reviewed

This paper presents outcomes from a course with focus on developing businesslike capabilities among undergraduate students. The purpose is to explore the need of trust in preparations of UI-collaboration and how outcomes are influencing trust in an education context. Findings indicate that word of mouth is essential to create needed trust. The amount of human resources students represent is found to be an important “qualifier”, while created trust is the “order winner” in the establishment of UI-collaboration. Godkänd; 2015; 20150116 (andbra)

A filter system to be used in order to reduce the radioactive pollution when reducing the pressure in the containment in case of a severe accident is developed. The radioactive pollution will be captured in the vessel that acts as a bubble column. To be able to maximize the water content in order to ensure that the radioactive pollution is captured it is of importance to predict the swelled water level in the vessel. In this study is three different methods to predict the gas holdup is presented and compared to experimental results; empirical correlations, thermal-hydraulic codes and Computational Fluid Dynamics (CFD). The advantages and disadvantages with the different methods are discussed. Both Computational Fluid Dynamics and the thermal hydraulic code (Gothic) show good predictions of the water level. Using empirical models it is crucial to have knowledge of the two-phase flow region in the bubble column.

Godkänd; 2014; 20141013 (andbra)

Godkänd; 2014; 20141013 (andbra)

Solar cells based on organic molecules or conjugated polymers attract great attention due to their unique advantages, such as low cost, and their use in flexible devices, but are still limited by their low power conversion efficiency (PCE). To improve the PCEs of polymer solar cells, more efforts have been made to increase short-circuit current (Jsc) or open-circuit voltage (Voc). However, the trade-off between Jsc and Voc in bulk heterojunctions solar cells makes it tricky to find a polymer with a low band gap to efficiently absorb photons in the visible and near infrared region of the solar spectrum, while maintaining a high Voc in solar cells. Therefore, it is crucial to design and synthesize polymers with energy levels aligning with the LUMO (lowest unoccupied molecular orbital) of an electron acceptor to minimize the LUMO level difference between donor and acceptor to keep enough driving force for charge generation, thereby maximizing photovoltage in solar cells. Here a novel copolymer APFO-Green 9 was synthesized. Polymer solar cells based on APFO-Green 9 blended with a derivative of fullerene demonstrate high photovoltage by fine tuning the HOMO and LUMO level of APFO-Green 9. Solar cells based on APFO-Green 9 and [6,6]-phenyl-C71-butyric acid methyl ester ([70]PCBM) present a photoresponse extended to 900 nm with Jsc of 6.5 mA cm 2, Voc of 0.81 V and PCE of 2.3% under illumination of AM1.5 with light intensity of 100 mW cm 2. As a low band gap polymer with a Voc bigger than 0.8 V, APFO-Green 9 is a promising candidate for efficient tandem solar cells. Refereed/Peer-reviewed

We report photo- and electroluminescence from an alternating conjugated polymer consisting of fluorene units and low-band gap donor-acceptor-donor (D–A–D) units. The D–A–D segment includes two elec ...

Problem: Forskning finns avseende vilka lägespreferenser köpare av småhus vanligen föredrar (Betts & Ely, 2008). Forskning finns även avseende hur marknadsföringspsykologi i form av varumärken påverkar konsumentens val av en vara (Arnold, 1993). Däremot har författarna till denna uppsats inte lyckats hitta annan forskning som kopplar samman marknadsföringsteori och bostadsområden, det vill säga hur varumärket påverkar köparens val av bostadsområde i samspel med praktiska faktorer. Studien vill även undersöka hur trendsättare som exempelvis kända personer och yrkesmän inom bostadsbranschen, kan påverka hur ett bostadsområdes efterfrågan kan komma att öka. Syfte: Studiens syfte är att undersöka vilka faktorer som kan få ett bostadsområde att öka alternativt minska i attraktivitet. Metod: För att komma fram till syftet har både kvalitativa och kvantitativa undersökningar utförts. Genom att noggrant välja ut fastighetsmäklare verksamma i Halmstad, har det genom öppna intervjuer framkommit viktig kunskap om vilka trender som råder på bostadsmarknaden i Halmstad. Med en kvantitativ datainsamling har sedan uppfattningen om olika lägespreferenser hos boende i Tylösand, Haverdal, Frösakull och Vishärad undersökts. Slutsats: Studien har kommit fram till att faktorer såsom närhet till kollektivtrafik, närhet till service, närhet till naturområden, rätt läge till solen samt att området är lugnt är viktigt för en köpare. Områdets varumärke har vidare visat sig ha en betydande roll för att vägleda köparen till rätt bostadsområde, samt att varumärket kan ha en avgörande betydelse när köpare väljer mellan bostadsområden i en konkurrenssituation (Arnold, 1993; Kotler et al., ; Melin, 1999). Sålunda, har dock kändisar visat sig ha liten betydelse för de boendes val av bostadsområde. Nyckelord: Bostadsområde, fastighetsvärde, läge, småhus, varumärke Problem: There is already some research regarding what location preferences house buyers usually prefer (Betts & Ely 2008). There is also research available regarding how marketing psychology in the form of brands, affect consumer choice of goods (Arnold, 1993). However, the authors of this essay were not able to find other research that links marketing theory and residential areas, in other words, how the brand affects the buyer's choice of residential area in close interplay with material factors. The study would also examine how trendsetters, such as celebrities and professionals in the residential sector, can affect how a residential area demand may increase. Purpose: The study aims to investigate factors which may increase and/or decrease the attractiveness of a residential area. Method: To reach the objective, both qualitative and quantitative studies were conducted. By carefully selecting the real estate agents operating in Halmstad, important knowledge has been found through open interviews about the latest trends in the housing market in Halmstad. With a quantitative data gathering, the perception of different location preferences among residents in Tylösand, Haverdal, Frösakull and Vishärad has been investigated. Conclusion: The study has concluded that the factors such as proximity to public transportation, close to services, proximity to natural areas, the correct position of the sun and to a quiet area is important for a buyer. The brand of the area has also been found to have a significant role to guide the buyer to the right neighborhood, and that brand can play a crucial role for the residents choice of residential (Arnold, 1993; Kotler et. al; Melin, 1999). However celebrities have only shown to have little importance on the residents choice of residential area. KeywordsResidential, propertyvalue, location, houses, branding