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  • 51.
    Bengtsson, Peder
    et al.
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Environmental and Life Sciences (from 2013). ASKO Appliances AB, Lidköping, Sweden.
    Berghel, Jonas
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Engineering and Chemical Sciences (from 2013).
    Concept Study of a New Method for Drying Dishware in a Heat Pump Dishwater2017In: Energy Efficiency, ISSN 1570-646X, E-ISSN 1570-6478, p. 1-10Article in journal (Refereed)
    Abstract [en]

    In a heat pump dishwasher, the whole dishwasher with the cabinet, dishware and process water is the heat sink, while a water tank, whose contents will freeze, is the heat source. The aim of the experimental concept study presented here was to evaluate a new drying method for a heat pump dishwasher. In this method, the drying of the dishware occurs as a fan circulates humid air in a closed system in which the water on the dishware evaporates inside the warm dishwasher cabinet and then condenses on a cold surface of the frozen water tank. The evaluation of drying performance was based on the European standard EN50242, which considers visible water drops left on the dishware after a completed dishwashing cycle. The results showed that this new closed drying method was more energy efficient compared to an existing open drying method, and that the drying start temperature and the drying time had a significant effect on the drying performance. Its lower electricity consumption and the fact that it does not vent humid air into the kitchen gives this heat pump dishwasher a competitive advantage over dishwashers using an open drying method.

  • 52.
    Bengtsson, Peder
    et al.
    ASKO Appliances AB, Sockerbruksgatan 3, SE-53140 Lidkoping, Sweden.
    Berghel, Jonas
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Engineering and Chemical Sciences (from 2013).
    Study of using a capillary tube in a heat pump dishwasher with transient heating2016In: International journal of refrigeration, ISSN 0140-7007, E-ISSN 1879-2081, Vol. 67, p. 1-9Article in journal (Refereed)
    Abstract [en]

    For competitive purposes, manufacturers of household appliances need to produce appliances that use less electricity. One way of doing this for a dishwasher is to add a heat pump system. Previous studies using R134a as refrigerant have shown that the addition of a heat pump can reduce total electricity consumption by about 24%. This paper reports on the use of a capillary tube in a heat pump dishwasher during the transient heating period. Working with an available compressor, the mass of R600a and the length of a 0.9 mm capillary tube were varied in order to find the configuration with the lowest electricity consumption. Three methods of calculating the length of the capillary tube were used to determine five lengths for evaluation. The results show that using a single capillary tube throughout the transient heating period yields similar electricity consumption to a variable expansion device which occurred by switching the capillary tube between two or three different lengths during the heating period.

  • 53.
    Bengtsson, Peder
    et al.
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Engineering and Chemical Sciences.
    Berghel, Jonas
    Karlstad University, Faculty of Technology and Science, Department of Energy, Environmental and Building Technology.
    Renström, Roger
    Karlstad University, Faculty of Technology and Science, Department of Energy, Environmental and Building Technology.
    A household dishwasher heated by a heat pump system using an energy storage unit with water as the heat source2015In: International journal of refrigeration, ISSN 0140-7007, E-ISSN 1879-2081, Vol. 49, p. 19-27Article in journal (Refereed)
    Abstract [en]

    Electricity usage by a household dishwasher can be reduced by using a heat pump system to heat the dishwasher cabinet, dishware and washing water. The evaporator obtains the energy from an energy storage unit which consists of a container filled with water which freezes to ice. The majority of the heat transfer from the energy storage to the evaporator occurs when ice is created in the energy storage unit. A transient simulation model of a dishwasher with a heat pump system was developed and compared to an experimental setup with good agreement. A simulation study of the compressor cylinder volume and the compressor operating time was performed. The results showed a 24% reduction in total electricity use compared to a dishwasher cycle using a traditional electric element.

  • 54.
    Bengtsson, Peder
    et al.
    ASKO Appliances AB, Lidköping, Sweden.
    Berghel, Jonas
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Engineering and Chemical Sciences.
    Renström, Roger
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Engineering and Chemical Sciences.
    Performance Study of a Closed-Type Heat Pump Tumble Dryer Using A Simulation Model and an Experimental Set-Up2014In: Drying Technology, ISSN 0737-3937, E-ISSN 1532-2300, Vol. 32, no 8, p. 891-901Article in journal (Refereed)
    Abstract [en]

    In the interests of competitiveness, manufactures of tumble dryers are seeking to reduce both their electricity use and the drying time. This study examines how the cylinder volume of the compressor and the total heat transfer of the condenser influence the drying time and electricity use in a heat pump tumble dryer. A transient simulation model was developed and compared to an experimental set-up with good similarity. The simulations show that increasing the cylinder volume of the compressor by 50% decreases the drying time by 14% without using more electricity.

  • 55.
    Berghel, Jonas
    et al.
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Engineering and Chemical Sciences.
    Frodeson, Stefan
    Karlstad University, Faculty of Technology and Science, Department of Energy, Environmental and Building Technology.
    Granström, Karin
    Karlstad University, Faculty of Technology and Science, Department of Energy, Environmental and Building Technology.
    Renström, Roger
    Karlstad University, Faculty of Technology and Science, Department of Energy, Environmental and Building Technology.
    Ståhl, Magnus
    Karlstad University, Faculty of Technology and Science, Department of Energy, Environmental and Building Technology.
    Nordgren, Daniel
    Innventia, Box 5604, SE-11486 Stockholm, Sweden.
    Tomani, Per
    Innventia, Box 5604, SE-11486 Stockholm, Sweden.
    The effects of kraft lignin additives on wood fuel pellet quality, energy use and shelf life2013In: Fuel processing technology, ISSN 0378-3820, E-ISSN 1873-7188, Vol. 112, no 0, p. 64-69Article in journal (Refereed)
    Abstract [en]

    In 2011, the total consumption of pellets in Sweden amounted to 1.9 million tons, which represents an energy value of 9 TWh. The pellets are used in large-scale as well as in small-scale applications, and increased demands on pellet quality are likely to force pellet producers to improve on the pellet properties. One way of increasing pellet quality is by using additives. The purpose of this article, therefore, is to examine kraft lignin as an additive. Pelletswere produced in a small industrial pellet press located at KarlstadUniversity, Karlstad, Sweden, and 1–4% of kraft lignin was added to the pellets. The results indicate that the addition of an increased amount of kraft lignin to the pellets increases their mechanical durability and their lengths. The results also indicate that dry kraft lignin yields pellets with higher durability as compared to wet kraft lignin. The energy demand was unaffected by the increased use of kraft lignin. The general results presented in this paper are useful for producers of lignin, pellet producers and end-users of pellets, who are interested in developing their products and/or improving the production processes.

  • 56.
    Berghel, Jonas
    et al.
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Engineering and Chemical Sciences.
    Renström, Roger
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Engineering and Chemical Sciences.
    An Experimental Study on the Influence of Using a Draft Tube in a Continuous Spouted Bed Dryer2014In: Drying Technology, ISSN 0737-3937, E-ISSN 1532-2300, Vol. 32, no 5, p. 519-527Article in journal (Refereed)
    Abstract [en]

    Further increasing the production of processed biofuel also increases the demands on drying capacity. With the aim of increasing the heat capacity flow, experimental tests have been performed on the process of drying sawdust in a continuous spouted bed dryer with nine different draft tube designs. The results showed that a draft tube with an increased length and an increased disengagement height decreased the dry substances' flow rate throughout the dryer. The results also showed that the mass of the material in the dryer was approximately the same in all the tests. This means that the draft tubes, no matter their size, do not influence the amount of material in the dryer.

  • 57.
    Berghel, Jonas
    et al.
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Engineering and Chemical Sciences.
    Renström, Roger
    Karlstad University, Faculty of Technology and Science, Department of Energy, Environmental and Building Technology.
    Shi yong dao liu guan dui lian xu pen dong gan zao qi de ying xiang: (Effects of using draft tubes in a continued spouted bed)2013In: Drying Technology & Equipment, ISSN 1727-3080, Vol. 1727-3080, no 3, p. 9-18Article in journal (Refereed)
  • 58.
    Berghel, Jonas
    et al.
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Engineering and Chemical Sciences (from 2013).
    Ståhl, Magnus
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Engineering and Chemical Sciences (from 2013).
    How residence time in the mixing conditioner affects the quality in wood fuel pellets2016Conference paper (Other academic)
  • 59.
    Berghel, Jonas
    et al.
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Engineering and Chemical Sciences (from 2013).
    Ståhl, Magnus
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Engineering and Chemical Sciences (from 2013).
    Frodeson, Stefan
    Karlstad University, Faculty of Technology and Science, Department of Energy, Environmental and Building Technology.
    The amount of dust and rejects as well as the electricity consumption during production decreases with the use of adequate additives2017Conference paper (Other academic)
  • 60.
    Berglund, Teresa
    et al.
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Environmental and Life Sciences.
    Gericke, Niklas
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Environmental and Life Sciences.
    Chang-Rundgren, Shu-Nu
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Engineering and Chemical Sciences.
    Investigating Swedish upper secondary students’ integrated understanding of sustainable development2013Conference paper (Refereed)
  • 61.
    Berglund, Teresa
    et al.
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Environmental and Life Sciences.
    Gericke, Niklas
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Environmental and Life Sciences.
    Chang-Rundgren, Shu-Nu
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Engineering and Chemical Sciences.
    The implementation of education for sustainable development in Sweden: Investigating the sustainability consciousness among upper secondary students2014In: Research in Science & Technological Education, ISSN 0263-5143, Vol. 32, no 3, p. 318-339Article in journal (Refereed)
    Abstract [en]

    Background: Sustainable development (SD) is a complex idea, based on environmental, economic and social dimensions. In line with SD, education for sustainable development (ESD) is an approach to teaching that combines cognitive and affective domains and aims to build empowerment abilities.

    Purpose: The purpose of this article is to investigate effects of the implementation of ESD in Sweden, in terms of developing students’ sustainability consciousness (SC). Two groups of students were included: one was from schools with a profile of ESD and the other one was from comparable schools without explicit ESD-profile.

    Sample: A total of 638 students from upper secondary schools (grade 12) in science-related or social science-related programs participated in the study.

    Design and methods: A procedure was created for the selection of schools considered to be the most active in using an ESD approach as well as comparable schools with no explicit ESD approach. During spring 2013, the students responded to a questionnaire based on sustainability knowingness, attitudes and behaviors within the environmental, economic and social dimensions of SD that together constitute the concept of SC. Data were analyzed using SPSS software.

    Results: The results indicate that there are significant differences in SC between students from schools that teach with an ESD approach compared to students from regular schools. Furthermore, a significant difference between the two groups of students was found in the underlying economic dimension of SC. No significant differences were found in the environmental and social dimensions of SC.

    Conclusions: Although the results show that ESD-profiled schools have effect on students' SC, the effects are relatively small. Therefore, the effects and nature of the implementation of ESD are discussed.

  • 62.
    Bergqvist, Anna
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Engineering and Chemical Sciences (from 2013).
    Teaching and learning of chemical bonding models: Aspects of textbooks, students’ understanding and teachers’ professional knowledge2017Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    Despite the growing importance of science and technology in society, school students consider these subjects irrelevant and hard to learn. Teachers must therefore know how to teach science in ways that enhance students’ understanding and interest. This thesis explores various aspects of the teaching and learning of chemical bonding, an important topic in school chemistry that is primarily taught using models. Research has shown that students find chemical bonding difficult to understand, and that the use of models in science education contributes to this difficulty. I therefore investigated teachers’ knowledge of how to teach chemical bonding and ways of developing it to improve students’ understanding. To this end, I analysed chemistry textbooks and teachers’ lesson plans, and conducted semi-structured interviews with teachers about their teaching of chemical bonding. This revealed that the representations of chemical bonding used in textbooks and by teachers can cause students difficulties. The teachers were generally unaware of how these representations might affect students’ understanding, implying that their pedagogical content knowledge (PCK) could be improved. To explore ways of incorporating research findings into teaching practice and developing teachers’ PCK, I conducted a learning study in which three secondary science teachers together explored and reflected on their own teaching practice. CoRe, a method for creating detailed descriptions of what, how, and why specific content is taught, was used to enhance the reflections and make the teachers’ PCK explicit. As a result, the teachers developed their representations of chemical bonding, became more aware of students’ understanding, and were better able to motivate their actions and choices of content and strategies.

    This thesis shows how professional development can bridge the gap between research and teaching practice, and how teachers’ PCK can be developed to improve students’ understanding.

  • 63.
    Bergqvist, Anna
    et al.
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Engineering and Chemical Sciences (from 2013).
    Chang Rundgren, Shu-Nu
    Stockholm universitet.
    The influence of textbooks on teachers’ knowledge of chemical bonding representations relative to students’ difficulties understanding2017In: Research in Science & Technological Education, ISSN 0263-5143, E-ISSN 1470-1138, Vol. 35, no 2, p. 215-237Article in journal (Refereed)
    Abstract [en]

    Background: Textbooks are integral tools for teachers’ lessons. Several researchers observed that school teachers rely heavily on textbooks as informational sources when planning lessons. Moreover, textbooks are an important resource for developing students’knowledge as they contain various representations that in uence students’ learning. However, several studies report that students have di culties understanding models in general, and chemical bonding models in particular, and that students’ di culties understanding chemical bonding are partly due to the way it is taught by teachers and presented in textbooks.

    Purpose: This article aims to delineate the in uence of textbooks on teachers’ selection and use of representations when teaching chemical bonding models and to show how this might cause students’ di culties understanding.

    Sample: Ten chemistry teachers from seven upper secondary schools located in Central Sweden volunteered to participate in this study. Design and methods: Data from multiple sources were collected and analysed, including interviews with the 10 upper secondary school teachers, the teachers’ lesson plans, and the contents of the textbooks used by the teachers.

    Results: The results revealed strong coherence between how chemical bonding models are presented in textbooks and by teachers, and thus depict that textbooks in uence teachers’ selection and use of representations for their lessons. As discussed in the literature review, several of the selected representations were associated with alternative conceptions of, and di culties understanding, chemical bonding among students.

    Conclusions: The study highlights the need for lling the gap between research and teaching practices, focusing particularly on how representations of chemical bonding can lead to students’ di culties understanding. The gap may be lled by developing teachers’ pedagogical content knowledge regarding chemical bonding and scienti c models in general. 

  • 64.
    Bergqvist, Anna
    et al.
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Engineering and Chemical Sciences.
    Drechsler, Michal
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Engineering and Chemical Sciences.
    Chang Rundgren, Shu-Nu
    Stockholm Univ, Dept Educ, S-10691 Stockholm, Sweden..
    Upper Secondary Teachers' Knowledge for Teaching Chemical Bonding Models2016In: International Journal of Science Education, ISSN 0950-0693, E-ISSN 1464-5289, Vol. 38, no 2, p. 298-318Article in journal (Refereed)
    Abstract [en]

    Researchers have shown a growing interest in science teachers' professional knowledge in recent decades. The article focuses on how chemistry teachers impart chemical bonding, one of the most important topics covered in upper secondary school chemistry courses. Chemical bonding is primarily taught using models, which are key for understanding science. However, many studies have determined that the use of models in science education can contribute to students' difficulties understanding the topic, and that students generally find chemical bonding a challenging topic. The aim of this study is to investigate teachers' knowledge of teaching chemical bonding. The study focuses on three essential components of pedagogical content knowledge (PCK): (1) the students' understanding, (2) representations, and (3) instructional strategies. We analyzed lesson plans about chemical bonding generated by 10 chemistry teachers with whom we also conducted semi-structured interviews about their teaching. Our results revealed that the teachers were generally unaware of how the representations of models they used affected student comprehension. The teachers had trouble specifying students' difficulties in understanding. Moreover, most of the instructional strategies described were generic and insufficient for promoting student understanding. Additionally, the teachers' rationale for choosing a specific representation or activity was seldom directed at addressing students' understanding. Our results indicate that both PCK components require improvement, and suggest that the two components should be connected. Implications for the professional development of pre-service and in-service teachers are discussed.

  • 65.
    Bergqvist, Anna
    et al.
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Engineering and Chemical Sciences.
    Drechsler, Michal
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Engineering and Chemical Sciences.
    De Jong, Onno
    Utrecht University, Netherlands .
    Chang Rundgren, Shu-Nu
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Engineering and Chemical Sciences.
    Representations of chemical bonding models in school textbooks: Help or hindrance for understanding?2013In: Chemistry education, ISSN 1109-4028, E-ISSN 1109-4028, Chemistry Education Research and Practice, ISSN 1109-4028, Vol. 14, p. 589-606Article in journal (Refereed)
    Abstract [en]

    Models play an important and central role in science as well as in science education. Chemical bonding is one of the most important topics at upper secondary school chemistry, and this topic is dominated by the use of models. In the past decade, research has shown that chemical bonding is a topic that students find difficult, and therefore, a wide range of alternative conceptions are developed by students. This study focuses on analyzing the models of chemical bonding in chemistry textbooks at upper secondary level and aims to investigate the content of chemical bonding presented in chemistry textbooks with respect to students’ learning difficulties (alternative conceptions and difficulties in understanding). Chapters concerning chemical bonding in five chemistry textbooks at upper secondary level in Sweden were analyzed. The results showed that the models of chemical bonding represented in the school textbooks might cause students’ alternative conceptions and difficulties in understanding chemical bonding, which matched the findings found by other recent studies. Implications for textbooks’ authors and teachers are addressed.

  • 66.
    Bergqvist, Anna
    et al.
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Engineering and Chemical Sciences (from 2013).
    Rundgren, Shu-Nu Chang
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Engineering and Chemical Sciences (from 2013).
    Developing science teachers’ pedagogical content knowledge - systematically reflections of teaching practice during a Learning Study combined with Content RepresentationsManuscript (preprint) (Other (popular science, discussion, etc.))
  • 67.
    Bergqvist, Liv
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Engineering and Chemical Sciences.
    Förbehandling av skogsindustriellt avloppsvatten i pilotskala: Fluidiserad biofilmsprocess, robust försteg till luftad damm2016Independent thesis Basic level (university diploma), 15 credits / 22,5 HE creditsStudent thesis
    Abstract [en]

    Paper mill wastewater passes through several different purification steps before being reintroduced to the recipient. Stora Enso paper mill in Skoghall uses an aerated lagoon with sludge recirculation as biological treatment. Extractives in wastewater aggravates the aeration in the pond and problems with the purification can occur when stricter emission requirements needs to be followed from 2018. Stora Enso is now running an investment project to improve the efficiency of the wastewater treatment to enable future production growth while stricter emission standards are followed. A pre-treatment step before the aerated lagoon designed as a MBBR (Moving Bed Biofilm Reactor) will be analyzed to present whether it can ease the wastewater treatment in the aerated lagoon or not. If so, production growth could be possible without change the present aerated lagoon while emissions conditions are met. This is a further investigation from Karin Arvsells work that studied a MBBR and aerated lagoon in lab scale. Large differences between these studies are that the wastewater goes to the pre-treatment continuously and the temperature is not regulated.

    A pilot plant was built at Stora Enso Skoghall mill where a Cipax-tank was used as a reactor and an aerator was built with membrane from the aerated lagoon. A partial flow of the total wastewater flow to the aerated lagoon was passed to the reactor at the bottom of the tank. The incoming wastewater and the aerator mixed 800 liters of water with the microorganisms growing as a biofilm on the carriers. The hydraulic retention time was controlled with a manual valve.

    TOC- and chlorate reduction, extractives, nitrogen, phosphorus, suspended solids, temperature, VFA, SVI, EDTA, HRT and oxygen content are analyzed to find out how robust the pre-treatment is. Tests were made to analyze how effective the oxygen dissolves after a pre-treatment and to identify the microorganisms in the wastewater.

    The experiments were divided into three different periods. Under the first 19 days was trial 1 performed where the water reacted in the MBBR without carriers. Trial 2 was 45 days long and the wastewater was pre-treated with microorganisms growing on carriers. Trial 3 lasted for 16 days and then the wastewater was treated in an isolated tank with carriers. The design of trial 3 was a result of the test results from trial 2 where the temperature dropped significantly during the hours the wastewater was treated in the reactor.

    Trial 2 showed reduction of all parameters with an average reduction of 40 % of TOC and 86 % reduction of chlorate. Surface tension analysis demonstrated a higher surface tension after the pre-treatment step which indicates that extractives were decomposed. The higher surface tension will ease the aeration in the aerated lagoon which was shown in the aeration tests were the rate of oxygen transport was doubled. Both free-swimming organisms and protozoa were found in the water.

    At the start of trial 3 the production of CTMP and the bleaching process were stopped. As a result, the remaining wastewater had a temperature of 51°C. The high temperature and the changed content of the wastewater at the same time as the reactor was isolated resulted in an elimination of the microorganisms. Chlorate was reduced by 93 % and TOC by 19 %. The reductions of the other parameters were lower than before and the aeration trials showed no improvement in oxygen transport.

    The reduction varied from day to day but since reasonable causes are known, the results are considered reliable. This means that a biological pre-treatment step in form of a MBBR can ease the purification in the aerated lagoon. Extractives are decomposed during the short reaction time and the oxygen transport is duplicated. If the production is disrupted, thermophilic conditions may occur instead of mesophilic conditions which are the normal setting. This may eliminate the microorganisms which affect the wastewater treatment negatively. To solve the problem, the hot water could be led directly to the aerated lagoon or by cooling the water keep the incoming temperature under 45°C.

  • 68.
    Bergström, Jens
    et al.
    Karlstad University, Faculty of Technology and Science, Materials Science. Karlstad University, Faculty of Technology and Science, Department of Mechanical and Materials Engineering.
    Fredriksson, Gunnel
    Karlstad University, Faculty of Technology and Science, Department of Mechanical and Materials Engineering. Karlstad University, Faculty of Technology and Science, Materials Science.
    Johansson, M
    Kotik, Ouliana
    Thuvander, Fredrik
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Paper Surface Centre. Karlstad University, Faculty of Technology and Science, Materials Science. Karlstad University, Faculty of Technology and Science, Department of Mechanical and Materials Engineering.
    The Use of Tool Steels: Experience and Research2002Book (Refereed)
  • 69.
    Bergström, Jens
    et al.
    Karlstad University, Faculty of Technology and Science, Materials Science. Karlstad University, Faculty of Technology and Science, Department of Mechanical and Materials Engineering.
    Thuvander, Fredrik
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Paper Surface Centre. Karlstad University, Faculty of Technology and Science, Materials Science. Karlstad University, Faculty of Technology and Science, Department of Mechanical and Materials Engineering.
    Devos, P.
    Boher, C.
    Wear of die materials in full scale plastic injection moulding of glassfibre reinforced polycarbonate2001In: Wear 251 2001 pp 1511-1521Article in journal (Refereed)
  • 70. Bergström, L.
    et al.
    Sjöberg, M.
    Järnström, Lars
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Paper Surface Centre. Karlstad University, Faculty of Technology and Science, Department of Chemical Engineering. Karlstad University, Faculty of Technology and Science, Materials Science.
    Concentrated Kaolinite Suspensions - Polymer Adsorption and Rheological Properties1996In: in "Science of Whitewares", ed. by V.E. Henkes, G.Y. Onoda and W.M. Carty, American Ceramic Society, Westerville, OH, 1996, pp. 65-77 / [ed] V.E. Henkes, G.Y. Onoda and W.M. Carty, 1996Chapter in book (Refereed)
  • 71. Bjorklund, R.B.
    et al.
    Arwin, H.
    Järnström, Lars
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Paper Surface Centre. Karlstad University, Faculty of Technology and Science, Department of Chemical Engineering. Karlstad University, Faculty of Technology and Science, Materials Science.
    Adsorption of Anionic and Cationic Polymers on Porous and Non-Porous Calcium Carbonate Surfaces1994In: Appl.Surf.Sci.,75,197(1994)Article in journal (Refereed)
  • 72. Björklund, L.
    et al.
    Larsson, S.
    Jönsson, Leif J
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Paper Surface Centre.
    Reimann, A.
    Nilvebrant, N.-O.
    Treatment with lignin residue ' a novel method for detoxification of lignocellulose hydrolysates2002In: Appl. Biochem. Biotechnol. (2002) 98-100, 563-575Article in journal (Refereed)
  • 73. Bohlin, C.
    et al.
    Andersson, P.-O.
    Lundquist, K.
    Jönsson, Leif J
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Paper Surface Centre.
    Differences in stereo-preference in the oxidative degradation of diastereomers of the lignin model compound 1-(3,4-dimethoxyphenyl)-2-(2-methoxyphenoxy)-1,3-propanediol with enzymic and non-enzymic oxidants2007In: J. Mol. Catal. B Enzym. (2007) 45, 21-26Article in journal (Refereed)
  • 74. Bohlin, C.
    et al.
    Jönsson, Leif J
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Paper Surface Centre.
    Roth, R.
    van Zyl, W.H.
    Heterologous expression of Trametes versicolor laccase in Pichia pastoris and Aspergillus niger2006In: Appl. Biochem. Biotechnol. (2006) 129-132, 195-214Article in journal (Refereed)
  • 75. Bohlin, C.
    et al.
    Persson, P.
    Gorton, L.
    Lundquist, K.
    Jönsson, Leif J
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Paper Surface Centre.
    Product profiles in enzymic and non-enzymic oxidations of the lignin model compound erythro-1-(3,4-dimethoxyphenyl)-2-(2-methoxyphenoxy)-1,3-propanediol2005In: J. Mol. Catal. B Enzym. (2005) 35, 100-107Article in journal (Refereed)
  • 76.
    Bohlin, Erik
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Engineering and Chemical Sciences.
    Surface and porous structure of pigment coatings: Interactions with flexographic ink and effects on print quality2013Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    Each day, we are confronted with a large amount of more or less important information that we have to consider, and even in our digital society we need paper for communication, documentation and education. Much of the paper we use or are confronted by in our daily life, such as newspapers, books and packages, contains printed images or texts, and the appearance of both the print and the supporting surface is important. A good contrast between a printed text and the paper makes it easier to read, a detailed print of an illustration makes it more informative, and clear and evenly distributed colours on a package or on a poster make it more appealing. All of these qualities depend on the optical properties of the paper product and the the behavior of light illuminating the different materials.

    The aim of the work described in this thesis is to characterize the structure of coatings and prints, and to validate models for the optical response and interaction of ink and coating based on optical measurements of physical samples. It is the interactions between the printing ink and the porous structure of the coating layers that are subject to investigation. Experiments have been employed to relate the physical conditions in a flexographic printing nip to the ink setting, affected by the physical and chemical properties of the coating, to the resulting optical response of the printed paperboard.

  • 77.
    Bohlin, Erik
    et al.
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Engineering and Chemical Sciences, Paper Surface Centre.
    Johansson, Caisa
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Engineering and Chemical Sciences, Paper Surface Centre.
    Lestelius, Magnus
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Engineering and Chemical Sciences, Paper Surface Centre.
    Evaluation of ink penetration in porous coatings2012Conference paper (Refereed)
  • 78.
    Bohlin, Erik
    et al.
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Engineering and Chemical Sciences.
    Johansson, Caisa
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Engineering and Chemical Sciences.
    Lestelius, Magnus
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Engineering and Chemical Sciences.
    Flexographic ink-coating interactions: Effects of kaolin clay/GCC blends in coating layersManuscript (preprint) (Other academic)
  • 79.
    Bohlin, Erik
    et al.
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Engineering and Chemical Sciences, Paper Surface Centre.
    Johansson, Caisa
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Engineering and Chemical Sciences, Paper Surface Centre.
    Lestelius, Magnus
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Engineering and Chemical Sciences, Paper Surface Centre.
    Flexographic ink-coating interactions: effects of kaolin clay/GCCblends in coating layers2014Conference paper (Refereed)
  • 80.
    Bohlin, Erik
    et al.
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Engineering and Chemical Sciences.
    Johansson, Caisa
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Engineering and Chemical Sciences.
    Lestelius, Magnus
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Engineering and Chemical Sciences.
    Flexographic ink-coating interactions: Effects of latex variations in coating layers2016In: TAPPI Journal, ISSN 0734-1415, Vol. 15, no 4, p. 253-262Article in journal (Refereed)
  • 81.
    Bohlin, Erik
    et al.
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Engineering and Chemical Sciences.
    Lestelius, Magnus
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Engineering and Chemical Sciences.
    Johansson, Caisa
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Engineering and Chemical Sciences.
    Flexographic Ink-Coating Interactions: Effects of Porous Structure Variations of Coated Paperboard2013In: Nordic Pulp & Paper Research Journal, ISSN 0283-2631, E-ISSN 2000-0669, Vol. 28, no 4Article in journal (Refereed)
    Abstract [en]

    Ink transfer and ink penetration into a coated surface, and variations thereof, influences the print density, mottling and dot gain, which affects the achievable print quality and visual appearance. The pressure in the printing nip and the porosity of the substrate are conditions and properties that will regulate the amount of ink that penetrates into a porous coating structure. The purpose of this study was to relate print quality aspects to ink penetration of water-based flexographic ink into calcium carbonate based coatings of differently engineered structures. Pilot-coated paper-boards with different coating porosities were printed in a laboratory flexographic printer. Results indicate that ink transfer distribution is strongly affected by the roughness and the porosity of the substrate. A coating layer of broad pigment particle size distribution resulted in a lower print density, compared to coatings of narrowly distributed particle sizes. A structure characterized by larger pore volume and greater dominating pore radius, showed a higher amount of z-directional ink penetration, which was supported by estimating the penetration using a physical model accounting for both capillary- and pressure driven penetration. A coating with narrow particle size distribution also showed a lower dot gain.

  • 82.
    Boudreau, Jonna
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Engineering and Chemical Sciences.
    New methods for evaluation of tissue creping and the importance of coating, paper and adhesion2013Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    The creping process and the conditions on the Yankee cylinder dryer are key factors in a tissue paper mill, and they therefore need to be kept under good control in order to maintain a high and uniform quality. To this end it would be valuable to be able to make on-line measurements of Yankee coating thickness as well as the crepe structure of the tissue paper. The adhesion of paper to the cylinder affects the creping process and more information about the parameters that affect the adhesion is therefore of interest. To perform trials on a full scale or in a pilot plant is very costly and laboratory creping equipment is therefore sought after in order to be able to measure the adhesion force.

    The coating layer for use on the cylinder was analysed. It contained a large amount of carbohydrates and could not be considered transparent. The thickness of the coating layer was measured on a laboratory cylinder with a method based on fluorescence. An optical brightener was added to the coating chemicals and the coating layer was subjected to UV-radiation. The intensity of the light emitted by the optical brightener was measured and gave an indication of the thickness of the coating layer. The equipment has to be further investigated before it is possible to implement the new sensor on-line.

    New creping equipment and an adhesion method were developed for use on a laboratory scale. The equipment can operate with different creping angles and the force needed to crepe the paper can be measured. The highest creping force was obtained for papers of high grammage, low dryness at adhesion, high drainability, high fines content and high hemicellulose content.

    A more direct method is to analyse the structure of the produced paper. Measurements were made on a tissue paper with an optical fibre sensor while the paper was travelling at low speed. The collected signal was mathematically analysed and the characteristic wavelength was calculated for different paper samples. These values were close to the wavelengths measured with an off line method by a commercial crepe analyser.

  • 83.
    Boudreau, Jonna
    et al.
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Engineering and Chemical Sciences.
    Barbier, Christophe
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Engineering and Chemical Sciences.
    Laboratory creping equipment2014In: Journal of Adhesion Science and Technology, ISSN 0169-4243, E-ISSN 1568-5616, Vol. 28, no 6, p. 561-572Article in journal (Refereed)
    Abstract [en]

    Tissue production is largely dependent on the creping process as creping influences the paper properties and thus the quality of the end product and the runnability of the tissue machine. The process is very complex and includes numerous variables affecting the adhesion, and ultimately the creping of the tissue paper. To perform experiments on a full scale machine, or even a pilot machine, is very costly, therefore a laboratory scale creping device is demanded, able to replicate conditions encountered on a tissue machine. In this paper new laboratory testing equipment is developed, whereby the adhesion between paper and metal surfaces (when scraping off the paper with configurations similar to the industrial process) can be studied. A new method to adhere paper to metal, used in the new laboratory creping equipment, is also developed. To evaluate the equipment, different creping angles were tested. The scraping tests show a trend in decreasing creping force for an increasing creping angle.

  • 84.
    Boudreau, Jonna
    et al.
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Engineering and Chemical Sciences.
    Germgård, Ulf
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Engineering and Chemical Sciences.
    Influence of Various Pulp Properties on the Adhesion Between Tissue Paper and Yankee Cylinder Surface2014In: BioResources, ISSN 1930-2126, E-ISSN 1930-2126, Vol. 9, no 2, p. 2107-2114Article, review/survey (Refereed)
    Abstract [en]

    The strength of the adhesion between the paper and the drying Yankee cylinder is of great importance with respect to the final properties of a tissue paper product. Therefore, the effects of a few potentially important pulp properties have been evaluated in laboratory experiments. Four highly different kraft pulps were used, and the adhesion strength was measured by means of the force required when scraping off a paper from a metal surface with a specifically designed knife mounted on a moving cart. The adhesion strength was observed to increase with increasing grammage and increasing degree of beating of the pulp. It was also found that pulpscontainingmore fines, or with higher hemicellulose content, gave rise to higher adhesion strength.

  • 85.
    Boudreau, Jonna
    et al.
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Engineering and Chemical Sciences.
    Mossberg, Magnus
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Engineering and Physics.
    Barbier, Christophe
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Engineering and Chemical Sciences.
    Experiments to Find On-line Measurements of the Structure of the Tissue Paper SurfaceArticle in journal (Refereed)
    Abstract [en]

    The structure of tissue paper has great influence on the quality of the resulting paper produced. One method of measuring the crepe wavelength on-line is sought in order to improve process control as well as to promote greater precision and uniform quality of the end product. In this study, a probe was used to read the surface of the paper whilst the paper travelled at a low speed. Light from a light emitting diode was emitted at a specific angle and collected at the corresponding reflecting angle, from the paper surface.

     

    Focusing the lenses at 45º angle produced results matching closest to the expected wavelength, and such measurements were made on a numerous commercial papers to validate the method. The collected signal contains a lot of information from the surface of the paper and from reflected signals inside the paper. The signal was processed using a mathematical approach to extract the most common wavelengths for each paper. The measured wavelength was found to closely match measurements made with commercial off-line equipment. This new method has a good initial potential to work on-line, however further investigation regarding the effects of high speeds upon the sampling still has to be carried out. 

  • 86.
    Breen, C.
    et al.
    Sheffield Hallam University, Sheffield, United Kingdom.
    Clegg, F.
    Sheffield Hallam University, Sheffield, United Kingdom.
    Thompson, S.
    Sheffield Hallam University, Sheffield, United Kingdom.
    Järnström, Lars
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Engineering and Chemical Sciences (from 2013).
    Johansson, C.
    Exploring the interactions between starches, bentonites and plasticizers in sustainable barrier coatings for paper and board2019In: Applied Clay Science, ISSN 0169-1317, E-ISSN 1872-9053, Vol. 183, article id 105272Article in journal (Refereed)
    Abstract [en]

    Effective food packaging is a major factor in the current global drive to minimise food waste. Starch is an excellent oxygen barrier for packaging but it is brittle and moisture sensitive. The addition of layered minerals and plasticizers can significantly improve the moisture barrier and flexibility of the resulting composite. Some combinations of starch and plasticizer are incompatible but our results show that the addition of bentonite ensures the formation of coherent starch films with much improved moisture barrier regardless of the starch-plasticizer compatibility. It was clearly demonstrated that improvement of the moisture barrier was critically dependent on the layer charge of the bentonite used. Starch was readily accommodated in the interlayer space of bentonites with a layer charge of <0.4 electrons per formula unit but was not adsorbed if the layer charge was above this value. Starch-bentonite-plasticizer coatings prepared using bentonites with the lower layer charge routinely produced higher barriers to water vapour. The water vapour transmission rate (WVTR) of the base paper was reduced from 780 to 340 ± 20 g m2 day−1 when coated with starch alone. This was further reduced to 48 or 66 g m2 day−1 if glycerol or lower charge bentonite, respectively, was added to the starch. Optimised coatings of starch-lower charge bentonite-plasticizer provided WVTR values of ≤10 g m2 day−1 whereas WVTR values for comparative coatings prepared using the higher charge bentonites were three to four times higher (35 ± 7 g m2 day−1). Scanning electron micrographs provided clear evidence for the presence of 60 nm thick supramolecular layers formed from starch-bentonite-plasticizer in the samples coated on either glass or paper. The WVTR values for these low-eco footprint coatings are competitive with proprietary coatings prepared using petroleum derived resins.

  • 87. Breen, Chris
    et al.
    Johansson, Caisa
    Karlstad University, Faculty of Technology and Science, Department of Chemical Engineering. Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Engineering and Chemical Sciences, Paper Surface Centre.
    Thompson, Simon
    Black, Leon
    Järnström, Lars
    Karlstad University, Faculty of Technology and Science, Department of Chemical Engineering. Karlstad University, Faculty of Technology and Science, Paper Surface Centre.
    Using clays to enhance the barrier properties of sustainable paper coatings2008Conference paper (Other (popular science, discussion, etc.))
  • 88.
    Brunzell, Lena
    et al.
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Engineering and Chemical Sciences (from 2013).
    Renström, Roger
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Engineering and Chemical Sciences (from 2013).
    Utformning av aktiva pedagogiska möten i en kurs med flippat lärande2018In: Studentaktiva lärande- och examinationsformer: Bidrag från universitetspedagogisk konferens 2017 / [ed] Madelaine Johansson, Lena E. Johansson, Karlstad: Karlstads universitet, 2018, p. 21-34Chapter in book (Other academic)
    Abstract [sv]

    Att använda flippat lärande i undervisningen har blivit mer och mer vanligt i högre utbildning. Studier pekar på att den formen av undervisning leder till ökad förståelse, ett ökat engagemang och motivation hos studenterna. Dock finns ett uttalat behov av ytterligare forskning inom området. I denna studie ligger fokus på hur de pedagogiska mötena i en typisk teknisk grundkurs kan utformas för att vara aktiva och främja lärandet i de högre kunskapsnivåerna. Den nya utformningen bygger på att traditionella möten med studenter såsom föreläsningar och lektioner har bytts ut mot diskussionstillfällen och laborationer. Räkneövningar finns i båda upplägg men fokus i det nya ligger i att arbeta med koncept och hur problem ställs upp. Den operativa räkningen lämnas alltid till studenterna. Resultaten blir att lärarna idag kan möta studenterna och agera som en coach i deras lärande, studenterna är mer aktiva och vi arbetar med kunskapsmål där vi analyserar, kritiskt utvärderar, utformar system och gör avvägda antaganden. Genomströmningen har ökat från mellan 40-50% till mellan 60-70% trots ett ökat krav på förståelsen i examinationen.

  • 89. Calvert, D.J.
    et al.
    Järnström, Lars
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Paper Surface Centre. Karlstad University, Faculty of Technology and Science, Department of Chemical Engineering. Karlstad University, Faculty of Technology and Science, Materials Science.
    Sundin, M.
    Larsson, A.
    Dynamic Test Procedures to Evaluate Runnability of Water-Based PSAs: Contact Angle Measurements under Non-Equilibrium Conditions1996In: Eur.Adhesives Sealants,June,2&4-5(1996)Article in journal (Refereed)
  • 90.
    Carlson, Carl-Johan
    et al.
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Engineering and Chemical Sciences (from 2013).
    Johansson, Albin
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Engineering and Chemical Sciences (from 2013).
    Simulering av ett värmeåtervinningbatteri med avseende på det svenska klimatet: Effekter av att reglera vätskeflöde efter utetemperatur2019Independent thesis Basic level (university diploma), 15 credits / 22,5 HE creditsStudent thesis
    Abstract [en]

    A growing population and need for energy in all forms is a fact, and with the justification for making a large amount of energy-related products more effective, the directive Eco-design was developed. Section 6 in the directive covers ventilation units, and specific requirements are set for different components within the unit. Eco-design oversees the entire European Union and the requirements that come with the directive create special problems, frost formation and freezing, for climates that, by comparison with the rest of Europe, are naturally colder. The purpose of this study is to investigate and evaluate whether the Ecodesign directive is suitable as a design method for the Swedish climate with regard to recycled energy, for liquid-coupled heat recovery systems. In collaboration with the company Aircoil, which specializes in various cooling systems, goal formulation was set, and the objective of this study was to focus on recovering as much energy as possible, by regulating the liquid flow in a liquid-coupled recycling system according to the current outdoor temperature and investigating what effects this flow control may have on temperature efficiency, total pressure drop and specific fan power (SFP). To reach the objective, the group got access to the software AC MasterSelection, which is the software used by Aircoil to make dimensioning calculations for liquid-coupled heat recovery systems. The software is certified and approved by Svensk Ventilation, which is the organization that represents the Swedish ventilation industry vis-à-vis authorities, government and the European Union - in terms of legislation and regulations. The software was used to obtain a large amount of data which was then compiled in Microsoft Excel to take flow variation profiles that generate higher recycling effect for the locations Malmö, Stockholm and Kiruna. The same profiles were then simulated in Matlab SimuLink to investigate the effect that a varying fluid flow has over the period of one year. Five different airflows for the heat recovery system were tested, 1 to 5 m3/s. According to the results, an estimated annual heat energy saving potential could be derived by utilizing a varying liquid flow for Malmö to be between 0.9 to 8.7%, for Stockholm between 1.1 to 4.4% and for Kiruna 3.3 to 15.8%. The results indicate that Eco-design and the regulations and requirements that come with the directive are not the most efficient design-wise from an energy recovery aspect for the Swedish climate, especially for the coldest locations, and that the electrical energy supplied to the system for the extra pump work is recovered in thermal energy to a much greater extent.

  • 91.
    Carlsson, Gunilla
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Paper Surface Centre. Karlstad University, Faculty of Technology and Science, Department of Chemistry and Biomedical Sciences. Karlstad University, Faculty of Technology and Science, Materials Science.
    Fluorescence Microscopy Applied to the Dynamics of Latex Colloids2003Licentiate thesis, monograph (Other academic)
  • 92.
    Carlsson, Gunilla
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Paper Surface Centre. Karlstad University, Faculty of Technology and Science, Department of Chemistry and Biomedical Sciences. Karlstad University, Faculty of Technology and Science, Materials Science.
    Latex Colloid Dynamics in Complex Dispersions2004Doctoral thesis, monograph (Other academic)
  • 93.
    Carlsson, Gunilla
    et al.
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Engineering and Chemical Sciences.
    Axrup, Lars
    Stora Enso, Karlstad Res Ctr, SE-65009 Karlstad, Sweden.
    Ljungqvist, Carl-Henrik
    Stora Enso, Karlstad Res Ctr, SE-65009 Karlstad, Sweden..
    Nyflott, Asa
    Stora Enso, Karlstad Res Ctr, SE-65009 Karlstad, Sweden.;Karlstad Univ, SE-65188 Karlstad, Sweden..
    The use of fluorescence microscopy and image analysis to characterize the porous structure in micro fibrillar cellulose gel - Part I: Brownian motion2013In: Nordic Pulp & Paper Research Journal, ISSN 0283-2631, E-ISSN 2000-0669, Vol. 28, no 2, p. 190-197Article in journal (Refereed)
    Abstract [en]

    The porous structure of a micro fibrilar cellulose, MFC, gel was studied by fluorescence microscopy and image analysis. The Brownian motion of fluorescent labelled carboxylated latex spheres, probes, was investigated at both high, 0.1-5 wt%, and low, 0-20 ppm, concentrations of MFC. The developed tracking program provides trajectories for probes. The trajectories can be studied according to either the individual approach or the ensemble approach to give complementary information regarding the fibrilar system. The Brownian motion can be used in the range 0 to 1.0 wt% MFC and the percentage of idle probes can be used when the concentrations exceeds 1.0 wt% MFC. The Brownian motion was found to be pH dependent both for the low and the high concentration regimes.

  • 94.
    Carlsson, Gunilla
    et al.
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Paper Surface Centre. Karlstad University, Faculty of Technology and Science, Department of Chemistry and Biomedical Sciences. Karlstad University, Faculty of Technology and Science, Materials Science.
    Järnström, Lars
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Paper Surface Centre. Karlstad University, Faculty of Technology and Science, Department of Chemical Engineering. Karlstad University, Faculty of Technology and Science, Materials Science.
    van Stam, Jan
    Karlstad University, Faculty of Technology and Science, Department of Chemistry and Biomedical Sciences. Karlstad University, Faculty of Technology and Science, Materials Science.
    Latex Diffusion at High Volume Fractions Studied by Fluorescence Microscopy2006In: J. Colloid Interface Sci. 298(1), 162-171 (2006)Article in journal (Refereed)
  • 95.
    Carlsson, Gunilla
    et al.
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Paper Surface Centre. Karlstad University, Faculty of Technology and Science, Department of Chemistry and Biomedical Sciences. Karlstad University, Faculty of Technology and Science, Materials Science.
    van Stam, Jan
    Karlstad University, Faculty of Technology and Science, Department of Chemistry and Biomedical Sciences. Karlstad University, Faculty of Technology and Science, Materials Science.
    Interactions between Charged Latex Colloids and Starch Polyelectrolytes Studied by Fluorescence Microscopy with Image Analysis2005In: Nordic Pulp Pap. Res. J., 2005, 20, 192-199Article in journal (Refereed)
  • 96.
    Carlén Bäckström, Lucas
    et al.
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Engineering and Chemical Sciences (from 2013).
    Mamghaderi, Javad
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Engineering and Chemical Sciences (from 2013).
    En studie om arbetsmiljö, tillbud, och risker inom produktion med fokus på kategorin fall2019Independent thesis Basic level (university diploma), 15 credits / 22,5 HE creditsStudent thesis
    Abstract [en]

    The working environment in construction production is an area that is exposed to a large amount of risks, incidents and accidents. Incidents and risk observations that are the step before accidents happens daily at the construction working environment, which entails an increased risk of someone being injured or even die while doing their works. No one need to hurt themselves or die while doing their jobs, a working environment should be a safe place for everyone. Therefore, the work environment agency, the construction industry and the construction companies in Sweden all are constantly working on improving the working environment in construction production. Although the construction industries has achieved a more well-developed and safer working environment than it was before in time, risks and accidents still happening. This project is carried out with support from the construction company Peab with the aim of strengthening the knowledge of why incidents, risk observations and accidents occur in construction production and within which category the greatest problem occurs. This project has been limited to incidents and accidents within the category of fall from higher altitude. The area in this category is one of the most dangerous working environment areas where the victims are exposed to the worst consequences. The method for this study was carried out through case studies on two different workplaces, questionnaires, interviews and literature study. After the report has been compiled with using all the method and the collected data, it turns out that even today there are problems regarding risk observations, incidents and accidents at the workplaces in construction production. The fact that there are risks in the working environments in construction production depends on many parameters. like lack in communication, plans/controls, deficiencies in attitude / human factor, lack of time/stress, deficiencies in performance and weather conditions are causes that lead to most risks, incidents and accidents. The conclusion shows that the most common incidents and risks that have occurred are related to the category fall which is refer to one area of some type of higher level that is very exposed area. The winter climate in Sweden has a direct connection to the fact that the incidents and the risks through falls and slips increase significantly during the winter months. Problems within the planning phase, the execution phase and the follow-up phase occurs and the basis for the problems depends in most cases on attitude or the human factor. The most important improvement measures in terms of attitude are that every individual must think for himself and consider being more cautious and take the security measures more seriously at the risky areas. Staying for a short while in the work process and thinking before carrying out the work can make a big difference, it will make the person who carrying out the work more caution which in turn will help with reducing accidents and incidents at workplaces in production. The recommendations presented show that there are a lot of improvement measures to take to make workplaces in production safer.

  • 97. Cassland, P.
    et al.
    Larsson, S.
    Nilvebrant, N.-O.
    Jönsson, Leif J
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Paper Surface Centre.
    Heterologous expression of barley and wheat oxalate oxidase in an E. coli trxB gor double mutant2004In: J. Biotechnol. (2004) 109, 53-62Article in journal (Refereed)
  • 98.
    Chang Rundgren, Shu Nu
    et al.
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Engineering and Chemical Sciences. Stockholm University.
    Nyberg, Lars
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Environmental and Life Sciences.
    Evers, Mariele
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Environmental and Life Sciences. Germany.
    Alexandersson, Jan
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Environmental and Life Sciences.
    Learning about flood risk: Comparing the Web-based and physical flood-walk learning environments2015In: Asia-Pacific Forum on Science Learning and Teaching, ISSN 1609-4913, E-ISSN 1609-4913, Vol. 16, no 1Article in journal (Refereed)
    Abstract [en]

    Numerous of sustainable development related challenges are emerging today, e.g. flooding problems. Our group has developed ’the flood walk’ project since 2010 to convey flood risk knowledge in an authentic context. Considering the limitation of time and space to educate people the flood risk knowledge, we tried to transform the physical flood walk field trip into a Web-based virtual trip. In this study, we aim to examine whether the Web-based flood-walk environment can help participants to achieve the same learning outcome as its authentic counterpart. A total of 65 upper secondary school pupils participated in this study. The results illustrate that a physical experience is irreplaceable, and the importance of providing physical experiences for learners in both formal and informal education needs to be emphasised.

  • 99.
    Chang-Rundgren, Shu-Nu
    et al.
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Engineering and Chemical Sciences.
    Gericke, Niklas
    Karlstad University, Faculty of Social and Life Sciences, Department of Biology.
    Research in Science Education: A Comparison between Sweden and Taiwan2011Conference paper (Refereed)
  • 100.
    Chang-Rundgren, Shu-Nu
    et al.
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Engineering and Chemical Sciences (from 2013). Stockholm University.
    Yao, Bao Jun
    Jiangxi Normal University, China.
    Visualization in research and science teachers’ professional development2014In: Asia-Pacific Forum on Science Learning and Teaching, ISSN 1609-4913, E-ISSN 1609-4913, Vol. 15, no 2Article in journal (Refereed)
    Abstract [en]

    Based on the importance and widely use of visualization in science, this article has a three-fold aim related to the terms of visualization, representation and model that in recent years have been introduced to the field of science education without clear differentiation. Firstly, the three terms are discussed with examples to provide a common ground for the following discussion. Secondly, the roles of visualization in science education are delineated to inform teachers how visualization can be used to enhance their teaching and students’ learning in science. Thirdly, based on visualization research in science education, there are a number of aspects that we need to consider while embedding the proposed visualization into the development of teachers’ professional knowledge. We hope to contribute to pre-and in-service science teachers’ professional development linked to the use of visualization in science education. © 2014 HKIEd APFSLT.

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