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  • 401.
    Adamopoulos, Stergios
    et al.
    Technological Educational Institute of Karditsa, Greece.
    Oliver, José-Vicente
    AIDIMA, Spain.
    Fiber composition of packaging grade papers as determined by the Graff “C” staining test2006In: Wood and Fiber Science, ISSN 0735-6161, Vol. 38, no 4, p. 567-575Article in journal (Refereed)
    Abstract [en]

    A qualitative and quantitative analysis of the fiber components of 15 representative papers that are used for the production of corrugated board was carried out by the Graff "C" staining test. The method of processing of softwood, hardwood, and nonwood fibers was determined under a light microscope by their color reactions with the stain. All papers, due to the use of recycled pulp raw materials in their manufacturing, were found to incorporate in their furnish fibers that had been produced with a variety of pulping processes: chemical, mechanical, and semi-mechanical. The recycled-based papers (recycled-liner and recycled-medium) were proved to be the most variable comprising 12-15 different fiber components, while in some of the semi-chemicals only up to 7 components were identified. The weight percentages of the fiber components calculated by the application of weight factors showed that in almost all papers the most important fiber component from a quantitative standpoint was hardwood unbleached kraft followed by softwood unbleached kraft. Besides hardwood unbleached semi-chemical pulp and mechanical softwood pulp that were also plentiful in the papers, there was a smaller number of other components which sum, however, accounted for a significant fraction in the total furnish weight. The results taken on the total softwood, hardwood, and nonwood fibers content of the papers demonstrate that Graff "C" staining test is adequate to analyze both the structure and quality of packaging grade papers in practical industrial testing.

  • 402.
    Adamopoulos, Stergios
    et al.
    Democritus University of Thrace, Greece.
    Oliver, José-Vicente
    AIDIMA, Spain.
    Qualitative and quantitative fibre analysis in recycled raw materials for packaging2006In: Forest products journal, ISSN 0015-7473, Vol. 56, no 2, p. 58-60Article in journal (Refereed)
    Abstract [en]

    Understanding the influence that heterogeneous recycled raw materials have on packaging-grade paper performance offers great potential value to the corrugated board and packaging industry. Fifty-seven linerboards and corrugating medium were selected to represent all the variety of paper grades available on the Spanish market at the moment for the production of corrugated board. The origin of softwood, hardwood, and nonwood fibers and their percentages by weight were determined with light microscopy and standard fiber analysis techniques.

  • 403. Adamopoulos, Stergios
    et al.
    Passialis, C
    Voulgaridis, E
    Prediction of bending and shear strength properties by using nondestructive parameters in fir and black locust2001Conference paper (Other academic)
  • 404.
    Adamopoulos, Stergios
    et al.
    Technological Educational Institute of Thessaly, Greece.
    Passialis, C
    Aristotle University of Thessaloniki, Greece.
    Voulgaridis, E
    Aristotle University of Thessaloniki, Greece.
    Oliver, JV
    Polytechnic University of Valencia, Spain.
    Grammage and structural density as quality indexes of packaging grade papers manufactured from recycled pulps2014In: Drewno, ISSN 1644-3985, Vol. 57, no 191, p. 145-151Article in journal (Refereed)
    Abstract [en]

    Corrugated packaging production is currently facing the challenge to ensure a satisfactory strength of packaging despite the continuous increase in recycled paper as the main fibrous component. This research addresses a very common technical problem for the corrugated board industry – the difficulty of predicting the properties of paper products produced from heterogeneous sources. Grammage and structural density, being easily available data, were examined as quality parameters of the most common categories of packaging paper in Europe. Grammage, ranging from 100 to 225 g/m2, has been found to be a dominant parameter for estimating the strength properties of paper.

  • 405.
    Adamopoulos, Stergios
    et al.
    Technological Educational Institute of Larissa, Greece.
    Passialis, Costas
    Aristotle University, Greece.
    Relationship of the toughness and the modulus of elasticity in static bending of small clear spruce wood specimens2010In: European Journal of Wood and Wood Products, ISSN 0018-3768, E-ISSN 1436-736X, Vol. 68, no 1, p. 109-111Article in journal (Refereed)
    Abstract [en]

    Unlike static bending, toughness is a mechanical property less commonly measured in clear wood. The paper presents results on the relationship of toughness and modulus of elasticity in static bending based on DIN standard tests on small, clear specimens of spruce, 2×2 cm2 in cross section.

  • 406. Adamopoulos, Stergios
    et al.
    Passialis, Costas
    Voulgaridis, Elias
    Fibre characteristics of papers used in European corrugated packaging industry2009In: ATIP. Association Technique de L'Industrie Papetiere, ISSN 0997-7554, Vol. 63, no 4, p. 14-21Article in journal (Refereed)
  • 407. Adamopoulos, Stergios
    et al.
    Passialis, Costas
    Voulgaridis, Elias
    Fibre characteristics of papers used in European corrugated packaging industry2008Conference paper (Refereed)
  • 408.
    Adamopoulos, Stergios
    et al.
    Technological Educational Institute of Larissa, Greece.
    Passialis, Costas
    Aristotle University, Greece.
    Voulgaridis, Elias
    Aristotle University, Greece.
    Ring width, latewood proportion and density relationships in black locust wood of different origins and clones2010In: IAWA Journal, ISSN 0928-1541, Vol. 31, no 2, p. 169-178Article in journal (Refereed)
    Abstract [en]

    Cross-sectional discs were cut at breast height from 19 black locust trees aged 18–39 years of different clones and origin (Greece, Bulgaria and Hungarian clones J, U and NY). Ring width, latewood proportion and dry density were measured according to standard laboratory techniques in order to examine their relationships. Latewood proportion was found to increase (except for one tree from Bulgaria) with increasing ring width and logarithmic equations were calculated with relatively high correlation coefficients. A positive relation between dry density and latewood proportion was found in black locust of Bulgarian origin and in the Hungarian clone NY while in all other cases no meaningful relationship was observed. In mature wood, improved positive linear correlations were observed between dry density and latewood proportion with the exception of the Hungarian clone U. Regression analysis revealed low correlations between dry density and ring width and only black locust from Bulgaria had a high positive correlation. The positive correlations between dry density and ring width were slightly improved in mature wood with the exception of clone J from Hungary.

  • 409.
    Adamopoulos, Stergios
    et al.
    Technological Educational Institute of Karditsa, Greece.
    Passialis, Costas
    Technological Educational Institute of Karditsa, Greece.
    Voulgaridis, Elias
    Aristotle University of Thessaloniki, Greece.
    Strength properties of juvenile and mature wood in black locust (Robinia pseudoacacia L.)2007In: Wood and Fiber Science, ISSN 0735-6161, Vol. 39, no 2, p. 241-249Article in journal (Refereed)
    Abstract [en]

    This study was undertaken to investigate the strength properties of juvenile and mature wood in black locust (Robinia pseudoacacia L.). Wood specimens were prepared from various stem heights, up to 9 m, of five naturally-grown black locust trees, 21-37 years old. Mechanical properties tested included moduli of rupture (MOR) and elasticity (MOE), and pure modulus of elasticity (PMOE) in static bending, stress wave modulus of elasticity (SWMOE) in dynamic strength, axial compression, and toughness. Comparisons between juvenile and mature wood specimens of similar densities (0.667-0.894 g/cm3 and 0.682-0.892 g/cm3, respectively) showed that juvenile wood had a statistically significant lower mean MOR (138.78 N/mm2), MOE (13,936 N/mm2), PMOE (18,125 N/mm2), SWMOE (16,813 N/mm2) and toughness strength (155.25 KJ/m2) than the mature wood (148.29 N/mm2, 14,747 N/mm2, 19,498 N/mm2, 17,635 N/mm2 and 181.27 KJ/m2, respectively). On the contrary, no statistically significant differences were found for the mean strength in axial compression among juvenile (63.75 N/mm2) and mature wood (66.65 N/mm2). Fractured surfaces of juvenile and mature wood specimens in static bending and toughness were classified into the "splintering tension" type of failure, while compression failures were of the "shearing type" according to ASTM D 143-83 standards. Lower strength of juvenile wood in most of the properties examined may be attributed to anatomical and chemical properties rather than density of wood specimens. The adverse influence of juvenile wood on strength properties should be considered for effective management (e.g. longer rotation age and other genetic and forest or plantation management measures that reduce juvenile wood content) and utilization of the species.

  • 410.
    Adamopoulos, Stergios
    et al.
    Technological Educational Institute of Thessaly, Greece.
    Passialis, Costas
    Aristotle University of Thessaloniki, Greece.
    Voulgaridis, Elias
    Aristotle University of Thessaloniki, Greece.
    Moustaizis, Stavros
    Technical University of Crete, Greece.
    Kortsalioudakis, Nathanail
    Technical University of Crete, Greece.
    Petrakis, Panagiotis
    Technical University of Crete, Greece.
    Karastergiou, Sotirios
    Technological Educational Institute of Thessaly, Greece.
    Foti, Dafni
    Technological Educational Institute of Thessaly, Greece.
    Koutsianitis, Dimitrios
    Technological Educational Institute of Thessaly, Greece.
    Voulgaridou, Eleni
    Technological Educational Institute of Thessaly, Greece.
    Effect of laser drilling on mechanical properties of fir (Abies borisii regis) and spruce (Picea excelsa) wood2014In: Wood Structure, Properties and Quality – 2014: 5th RCCWS International Symposium, Moscow State University Press, 2014, p. 7-12Conference paper (Refereed)
    Abstract [en]

    Fir and spruce wood specimens, 2×2 cm in cross section and 34 cm long, were pre-pared with true radial and tangential surfaces. All lateral surfaces of the wood specimens were drilled by laser beams to a depth of 0,4 cm (1/5 of specimen thickness) with two drilling pat-terns (distance between holes 1 × 1 cm and 1 × 2 cm). After drilling, static bending (MOR, MOE), axial compression strength and toughness were determined and compared with non-drilled control specimens. The effects of the two laser drilling patterns on mechanical proper-ties of fir and spruce wood specimens were measured and assessed. The results showed that the two drilling patterns created by laser beams on all lateral surfaces of fir and spruce wood specimens at 0,4 mm depth did not practically affect the mechanical properties of wood.

  • 411. Adamopoulos, Stergios
    et al.
    Passialis, Costas
    Voulgaridis, Elias
    Oliver, JV
    Utilization of recycled fibre materials in the European corrugated packaging industrial sector2008In: 2nd International Conference on Engineering for Waste Valorisation WasteEng08, June 3-5, Patras, Greece, 2008Conference paper (Refereed)
  • 412.
    Adamopoulos, Stergios
    et al.
    Linnaeus University, Faculty of Technology, Department of Forestry and Wood Technology.
    Säll, Harald
    Linnaeus University, Faculty of Technology, Department of Forestry and Wood Technology.
    Sjöberg, Samuel
    Relationship between ultrasonic velocity and spiral grain in standing hybrid aspen trees2016In: Proceedings of the Hardwood Conference, Eco-efficient Resource Wood with Special Focus on Hardwoods, 8-9 September, 2016, Sopron, Sopron: University of West Hungary Press , 2016, p. 22-23Conference paper (Refereed)
  • 413. Adamopoulos, Stergios
    et al.
    Voulgaridis, E
    Impregnation of timber and regulations applied to preservation practice in Greece1998Conference paper (Refereed)
    Abstract [en]

    The practice of wood preservation in Greece was started about 80 years ago and refer to creosote-treated timber used in ground contact (i.e. railway sleepers, poles). At present, three creosote impregnation plants and thirteen CCA or CCB units exist in Greece treating about 90.000 m3 of wood per year. Most of the research on wood preservation has been carried out in the last 15-20 years and refer to the application of creosote and water soluble preservatives (CCA, CCB) to native wood species. However, research on a number of specific topics of wood impregnation is lacking. Impregnation of wood is of great importance for Greece, a country with great wood deficit, and, for this reason, the elongation of wood durability is strongly desirable. On the other hand, the environmentally safe impregnation of timber and the use of preservatives in a non-hazardous manner to humans or animals are gaining an increasing importance. There are some national and EU regulations applied to the use of preservatives, while the Greek Organization of Standardization (ELOT) is responsible for approving European standards. The organizations of Greek Telecommunication, Electricity and Railway apply their own standards.

  • 414. Adamopoulos, Stergios
    et al.
    Voulgaridis, E
    Passialis, C
    Morphology and identification of fibre furnish components of papers used in the production of corrugated board2013In: Celuloza Si Harti, ISSN 1220-9848Article in journal (Refereed)
  • 415.
    Adamopoulos, Stergios
    et al.
    Aristotle University, Greece.
    Voulgaridis, Elias
    Aristotle University, Greece.
    Dimensional changes of extracted and non-extracted small wood specimens of black locust (Robinia pseudoacacia L.)2003In: European Journal of Wood and Wood Products, ISSN 0018-3768, E-ISSN 1436-736X, Vol. 61, no 4, p. 264-268Article in journal (Refereed)
    Abstract [en]

    From straight grained heartwood of black locust (Robinia pseudoacacia L.), specimens, 3 cm×3 cm in cross section and 0.5 mm (or 10 mm) in axial direction, were cut and used for the determination of dimensional changes and the rate of tangential swelling. Mean radial, tangential and axial shrinkage was 5.30%, 6.67% and 0.16%, respectively, while the coefficient of anisotropy was 1.26. Half of the specimens for the determination of the rate of tangential swelling were extracted for 48 h with distilled hot water. The tangential dimensional change and the time taken to attain half maximum swelling in air-dry and oven-dry specimens were assessed according to a common technique. Extractive removal resulted in an increase of the total magnitude of tangential swelling in both air-dry and oven-dry specimens. However, no significant differences in time taken to attain half maximum swelling between air-dry and oven-dry specimens were observed after extraction. The rate of tangential swelling was lower in air-dry specimens than in oven-dry specimens after 30 min of immersion in water when were non-extracted and after 5 min of immersion in water when were extracted. Extracted air-dry specimens had a greater rate of tangential swelling than non-extracted air-dry specimens and the same occurred for oven-dry specimens. Extraction resulted in a higher diffusion coefficient for air-dry specimens. The diffusion coefficient calculated for non-extracted air-dry specimens (0.901×10−4 cm2/min) showed that black locust is a difficult species to impregnate.

  • 416.
    Adamopoulos, Stergios
    et al.
    Technological Educational Institute of Larissa, Greece.
    Voulgaridis, Elias
    Aristotle University of Thessaloniki, Greece.
    Effect of hot-water extractives on water sorption and dimensional changes of black locust wood2012In: Wood research, ISSN 1336-4561, Vol. 57, no 1, p. 69-78Article in journal (Refereed)
    Abstract [en]

    The hygroscopicity and the dimensional changes of black locust heartwood were investigated in relation to the progressive removal of hot-water extractives. Extraction in the original specimen form removed only part of the total 8.434 % hot-water extractives, 3.601 % in first extraction and 4.642 % in second extraction. As a result, the adsorption and desorption behaviour of black locust wood was little affected by the extraction and only a small increase was observed in dimensional changes at every RH from 0 % to 97 %. The mean hysteresis coefficient was also little affected by extraction and increased from 0.75 at the unextracted stage to 0.77 at the second extraction. The initial dimensional change 3.76 % of unextracted black locust wood corresponding to RH changes between 43 % and 80 % increased after the first and second extraction to the respective values of 3.96 % and 3.97 %. Extraction had no effect on the significant, very strong linear relationships between swelling or shrinkage and equilibrium moisture content (EMC).

  • 417.
    Adamopoulos, Stergios
    et al.
    Aristotelian University, Greece.
    Voulgaridis, Elias
    Aristotelian University, Greece.
    Within-tree variation in growth rate and cell dimensions in the wood of black locust (Robinia pseudoacacia)2002In: IAWA Journal, ISSN 0928-1541, Vol. 23, no 2, p. 191-199Article in journal (Refereed)
    Abstract [en]

    Black locust (Robinia pseudoacacia L.) is regarded as an important natural resource almost throughout the world but relatively little is known about the within-tree variability of the anatomical characteristics of its wood. Discs 2 cm thick were cut at 2.25 m intervals, from the ground level to the top from ten black locust trees, 18–37-years-old, from the University Forest of Taxiarchi, Chalkidiki, Greece. The discs were used for the determination of growth rate and cell dimensions (fiber length and vessel member length and diameter) and their withintree variability (radial, oblique, vertical). Growth rate increased within the first 5–9 growth rings from the pith and then gradually decreased. Oblique variation of growth rate did not exhibit any clear tendency but a decrease at the top. In the case of vertical variation, growth rate decreased gradually with the year of cambium formation. Radial variability curves were found to be typical for the dimensions of cells (fibers, vessel members) especially for the fiber length. A rapid increase in cell dimensions was observed in the first 7–11 growth rings, the juvenile zone. Oblique and vertical variation of cell dimensions did not exhibit any clear tendencies.

  • 418.
    Adamopoulos, Stergios
    et al.
    Technological Educational Institute of Larissa, Greece.
    Voulgaridis, Elias
    Aristotle University of Thessaloniki, Greece.
    Ποιότητα και μεταβλητότητα της δομής του ξύλουσε σχέση με την αξιοποίησή του: [Quality and variability of wood structure in relation to its utilization]2012In: Το Δάσος: Μια Ολοκληρωμένη Προσέγγιση: [The forest: An integrated approach] / [ed] Aristotélis Papageorgíou, Geórgios Karétsos, Geórgios Katsadorákis, WWF Greece , 2012, p. 213-227Chapter in book (Other academic)
  • 419. Adamopoulos, Stergios
    et al.
    Voulgaridis, Elias
    Passialis, C.
    Wood quality characteristics of black locust (Robinia pseudoacacia  L.)2001In: Forest Research - New Series, Vol. 14, p. 63-72Article in journal (Refereed)
  • 420.
    Adamopoulos, Stergios
    et al.
    Technological Educational Institute of Thessaly, Greece.
    Voulgaridis, Elias
    Aristotle University of Thessaloniki, Greece.
    Passialis, Costas
    Aristotle University of Thessaloniki, Greece.
    CARACTERISTICILE MATERIALULUI FIBROS ŞI PROPRIETĂŢILEHÂRTIEI RECICLATE FOLOSITE ÎN FABRICAREA CARTONULUIONDULAT: Morphology and identification of fibre furnish components of papers used in the production of corrugated board2013In: 7th International Symposium on Advanced Technologies for the Pulp, Paper and Corrugated Board Industry, 2013Conference paper (Refereed)
    Abstract [en]

    The manufacture of corrugated board containers (boxes, trays, etc.) involves a productionchain integrated by paper manufacturers, semi-elaborates (corrugated board) manufacturers andcontainer manufacturers, the majority of which in Europe are SMEs. Nowadays, corrugated boardcontainers are mostly manufactured with recovered paper. The greatest threat faced by thementioned production chain is related to the lack of quality and availability of recovered paper asraw material. Specifically, one of the most important properties of packaging paper is itsmechanical strength, which depends mostly on the length of the fibres of which paper iscomposed. These fibres are longer in virgin pulps (those coming from papers obtained fromwood, i.e. not yet recycled). However, the high pressure on the demand - as well as the currenteconomic and ecological restrictions in the use of forest based materials - has led to a situation inwhich very little quantity of virgin fibre enters the recycling chain. This means that the strengthquality of recycled fibres - and by extension of the papers - is constantly decreasing with the ongoingrecycling cycles. In addition, recovered paper presents a very high variability, whatconstitutes an obstacle when it comes to manufacturing containers having homogeneousproperties fixed by the customers at fixed costs. The difficulty of predicting the properties ofpaper products produced from heterogeneous sources puts several limitations, which thereforelead to severe economic losses and only a comprehensive characterization will enable their betterutilization. The project “RF-CORRUG – Quality control of raw materials from recovered fibresfor the production of corrugated board” under the National Strategic Reference Framework 2007–2013 ARCHIMEDES III deals with this common technical problem of the corrugated boardindustry. Specifically, the main objective of the project is to support the competitiveness of thecorrugated board companies (mainly SMEs) by creating a software tool based on practical modelsthat can predict packaging grade paper properties from fibre data (qualitative, quantitative, morphological) used in their production. This papers presents information on fibres (qualitativeand quantitative analysis, morphology) and packaging papers (physical and mechanicalproperties) used in corrugated packaging. A number of different category papers (liners, flutings) used for corrugated board production in Greece were examined. The main fibre characterizingtechniques, employed were fibre furnish analysis, morphological analysis of fibre, lightmicroscopy, scanning electron microscopy (SEM). In addition, zero span tensile test was done tomeasure the average fibre strength of fibre. The required paper properties were measured byinternationally recognized testers and standards. The data will be used to develop predictivemodels based on advanced statistical methods for the properties and performance of packagingpapers according to information of their fibres.

  • 421.
    Adamopoulos, Stergios
    et al.
    Technological Educational Institute of Thessaly, Greece.
    Voulgaridis, Elias
    Aristotle University of Thessaloniki, Greece.
    Passialis, Costas
    Aristotle University of Thessaloniki, Greece.
    Gypsum-based bricks (WoodRub BRICKS) manufactured from recovered wood and rubber2014In: Performance and maintenance of biobased building materials influencing the life cycle and LCA / [ed] Andreja Kutnar, Miha Humar, Michael Burnard, Mojca Žlahtič, Dennis Jones, 2014, p. 33-34Conference paper (Other academic)
  • 422.
    Adamopoulos, Stergios
    et al.
    Greece.
    Voulgaridis, Elias
    Greece.
    Passialis, Costas
    Greece.
    Recycled Waste Paper and the Corrugated Packaging Industry in Europe2009In: Proceedings of 24th International Conference on Solid Waste Technology and Management: Philadelphia, PA USA, March 15-18, 2009, 2009, p. 400-411Conference paper (Refereed)
  • 423.
    Adamopoulos, Stergios
    et al.
    Aristotle University, Greece.
    Voulgaridis, Elias
    Aristotle University, Greece.
    Passialis, Costas
    Aristotle University, Greece.
    Variation of certain chemical properties within the stemwood of black locust (Robinia pseudoacacia L.)2005In: European Journal of Wood and Wood Products, ISSN 0018-3768, E-ISSN 1436-736X, Vol. 63, no 5, p. 327-333Article in journal (Refereed)
    Abstract [en]

    From the bottom, middle, and top of three mature 35 to 37-year old black locust tree discs were cut and analysed to determine the variation within the stem of certain chemical properties. Hot-water extractive content was greater in heartwood than in sapwood, while the reverse occurred for the dichloromethane extractive content. Vertical stem analysis of hot-water extractives showed that they increased in heartwood but decreasedin sapwood from the bottom to the top of the stems while the reversal occurred for dichloromethane extractive content of sapwood. At the bottom and the middle of the stems, ash content was greater in sapwood than in heartwood, but at the top no difference was found between heartwood and sapwood. Ash content of both heartwood and sapwood was found to increase in the axial direction with respective values of 0.36% (bottom) and 0.76% (top) for heartwood and of 0.65% (bottom) and 0.76% (top) for sapwood. Ash analysis showed that considerable variations were found for the inorganic elements K and P being greater in sapwood than in heartwood. Heartwood was more acid than sapwood except for the top of the stems. Acidity mean values were found to increase from the bottom to the top of the stems in heartwood while they slightly decreased in sapwood. Total buffering capacity of heartwood was greater than that of sapwood and total buffering capacity of sapwood exhibited an inverse relationship to height. Very small acid equivalent values were determined only in sapwood. At the bottom, lignin content in heartwood (25.73%) was greater than in sapwood (18.13%). Lignin content of heartwood decreased from 25.73% at the bottom to 18.33% at the top, while that of sapwood was 18.13% at the bottom, 21.42% at the middle and 19.64% at the top.

  • 424.
    Adamopoulos, Stergios
    et al.
    Technological Educational Institute of Larissa, Greece.
    Voulgaridis, Elias
    Aristotle University of Thessaloniki, Greece.
    Passialis, Costas
    Aristotle University of Thessaloniki, Greece.
    Wood recycling in Europe2011Conference paper (Refereed)
    Abstract [en]

    Nowadays, waste wood is a valuable secondary raw material that can cover much of the wood-based panel industry's needs and a major source of renewable energy. The various categories of waste wood are described in European legislation and standards but in practice mostly followed industry practices relating to the purchase, classification and use of recovered wood. The European Panel Federation (EPF) proposes a three category classification system: untreated wood, non-hazardous treated wood, hazardous waste wood. The traditional practice of recycling in industry included mechanical handling of waste wood while new improved methods involve hydrothermal treatments. Of the total approximately 30 million cubic meters of recovered wood in Europe 38% is recycled, 34% is used for energy production and 28% ends up in landfills or composting. In the future recovered wood is expected to play an increasingly important role in the sustainability of wood-based panel industries as well as for the protection of the environment, and therefore new technologies are needed to fully explore this valuable resource.

  • 425.
    Adamopoulos, Stergios
    et al.
    Technological Edicational Institute of Larissa, Greece.
    Voulgaridis, Elias
    Aristotle University, Greece.
    Passialis, Costas
    Aristotle University, Greece.
    Beaver, Tim
    Composites & Textiles Pera, UK.
    Bouras, Takis
    ELKEDE Technology & Design Centre S.A., Greece.
    Properties of Microwave heat treated oak wood and impregnated with soybean oil2011In: Program & Book of Abstracts: Workshop, “Mechano-Chemical transformations of wood during Thermo-Hydro-Mechanical processing” / [ed] Parviz Navi, Andreas Roth, 2011, p. 145-145Conference paper (Other academic)
    Abstract [en]

    The poster presents selected data on physical and mechanical properties, and gluing behaviour of microwave heat treated wood and impregnated with natural oils.

  • 426.
    Adamopoulos, Stergios
    et al.
    Technological Education Institute of Larissa, Greece.
    Wimmer, Rupert
    Georg-August-University Göttingen, Germany.
    Milios, Elias
    Democritus University of Thrace, Greece.
    Tracheid length – growth relationships of young Pinus brutia grown on reforestation sites2012In: IAWA Journal, ISSN 0928-1541, Vol. 33, no 1, p. 39-49Article in journal (Refereed)
    Abstract [en]

    Brutia pine (Pinus brutia Ten.) reforestations have been successfully used for decades in restoration of degraded forest ecosystems in Greece. The future purpose of these reforestations might expand to include wood utilisation. This study provides information on tracheid length of juvenile brutia pine aged 14–22 years grown on good and medium sites in Northeastern Greece. In addition, relationships among ring width, latewood proportion, wood density, and tracheid length were evaluated by using Causal Correlation Analysis. Similar mean tracheid length values were found for good and medium sites. Radial variability of tracheid length was similar on the good and medium sites, showing the typical increase in the juvenile phase. On both site types, latewood proportion showed a strong and positive relationship with wood density. Unexpectedly and only on the good sites, a significant positive relationship was found between ring width and wood density. On the medium sites, tracheid length was negatively related to fast growth and positively to high wood density. Tracheid length on the good sites was correlated only with latewood proportion with a weak positive relationship. The overall results may provide opportunities to better understand the quality of small-dimension timber of brutia pine and to better utilise it.

  • 427.
    Adamopoulos, Stergios
    et al.
    Georg-August-University Goettingen, Germany ; Technological Educational Institute of Larissa, Greece.
    Xie, Yanjun
    Georg-August-University Goettingen, Germany.
    Militz, Holger
    Georg-August-University Goettingen, Germany.
    Distribution of blue stain in untreated and DMDHEU treated Scots pine sapwood panels after six years of outdoor weathering2011In: European Journal of Wood and Wood Products, ISSN 0018-3768, E-ISSN 1436-736X, Vol. 69, no 2, p. 333-336Article in journal (Refereed)
    Abstract [en]

    Surface coating and bulk treatment of wood are two effective measures which can, individually or conjointly, protect exterior wood from deterioration. This paper reports on the blue stain attack in coated wood, untreated and modified with DMDHEU, after six years of natural exposure.

  • 428.
    Adamou, Sofia
    et al.
    Linnaeus University, Faculty of Technology, Department of Informatics.
    Ntoka, Lamprini
    Linnaeus University, Faculty of Technology, Department of Informatics.
    The impact of Digital Technologies on Academic Libraries: a study in Greece2017Independent thesis Advanced level (degree of Master (Two Years)), 80 credits / 120 HE creditsStudent thesis
    Abstract [en]

    Purpose: This study explores both library users’ and librarians’ experiences, benefits, and challenges depending on the implementation of digital technologies in academic libraries. The research has been taken place in two Greek academic libraries; In the Panteion University Library and in the Central Library of T.E.I. of Athens.Approach: Two research questions were developed for this research to be conducted and a sample size of 55 respondents (39 library users and 16 librarians) of the Panteion University Library and Central Library of T.E.I. of Athens, was evaluated.Findings: From the findings of the study, it was concluded that the general perception of both library users and librarians towards digital material and E-resources and services of the Panteion University Library and Central Library of T.E.I. of Athens, is satisfactory. Library users were satisfied with the convenience of digital material, the availability of E-resources provided by both academic libraries such as World Wide Web, WIFI, and online databases. They were not satisfied with library technology (i.e., computers) and library staff. Besides, results showed that services such as e-mail and Open Public Access Catalogue were used more often. Librarians were less satisfied with the digital library system, the limited personnel, and the financial funds for academic libraries in general.Implication: The results of this research have implications in the stakeholders of an academic library including the institutional management, the library administration, the librarians, the library users, the researchers, the community at large, and others.Value: This paper identifies critical issues related to the utilization of digital technologies and digital material; their benefits and challenges faced by librarians and library users as well as their effective operation from academic libraries in this information age.

  • 429.
    Adams, Marc A.
    et al.
    Arizona State University, USA.
    Ding, Ding
    University of Sydney, Australia.
    Sallis, James F.
    University of California, USA.
    Bowles, Heather R.
    National Institutes of Health, USA.
    Ainsworth, Barbara E.
    Arizona State University, USA.
    Bergman, Patrick
    Linnaeus University, Faculty of Social Sciences, Department of Sport Science.
    Bull, Fiona C.
    The University of Western Australia, Australia.
    Carr, Harriette
    Ministry of Health, New Zealand.
    Craig, Cora L.
    School of Public Health, Canada.
    De Bourdeaudhuij, Ilse
    Ghent University, Belgium.
    Fernando Gomez, Luis
    Hagstromer, Maria
    Klasson-Heggebo, Lena
    Inoue, Shigeru
    Lefevre, Johan
    Macfarlane, Duncan J.
    Matsudo, Sandra
    Matsudo, Victor
    McLean, Grant
    Murase, Norio
    Sjostrom, Michael
    Tomten, Heidi
    Volbekiene, Vida
    Bauman, Adrian
    Patterns of neighborhood environment attributes related to physical activity across 11 countries: a latent class analysis2013In: International Journal of Behavioral Nutrition and Physical Activity, ISSN 1479-5868, E-ISSN 1479-5868, Vol. 10, article id 34Article in journal (Refereed)
    Abstract [en]

    Background: Neighborhood environment studies of physical activity (PA) have been mainly single-country focused. The International Prevalence Study (IPS) presented a rare opportunity to examine neighborhood features across countries. The purpose of this analysis was to: 1) detect international neighborhood typologies based on participants' response patterns to an environment survey and 2) to estimate associations between neighborhood environment patterns and PA. Methods: A Latent Class Analysis (LCA) was conducted on pooled IPS adults (N=11,541) aged 18 to 64 years old (mean=37.5 +/- 12.8 yrs; 55.6% women) from 11 countries including Belgium, Brazil, Canada, Colombia, Hong Kong, Japan, Lithuania, New Zealand, Norway, Sweden, and the U. S. This subset used the Physical Activity Neighborhood Environment Survey (PANES) that briefly assessed 7 attributes within 10-15 minutes walk of participants' residences, including residential density, access to shops/services, recreational facilities, public transit facilities, presence of sidewalks and bike paths, and personal safety. LCA derived meaningful subgroups from participants' response patterns to PANES items, and participants were assigned to neighborhood types. The validated short-form International Physical Activity Questionnaire (IPAQ) measured likelihood of meeting the 150 minutes/week PA guideline. To validate derived classes, meeting the guideline either by walking or total PA was regressed on neighborhood types using a weighted generalized linear regression model, adjusting for gender, age and country. Results: A 5-subgroup solution fitted the dataset and was interpretable. Neighborhood types were labeled, "Overall Activity Supportive (52% of sample)", "High Walkable and Unsafe with Few Recreation Facilities (16%)", "Safe with Active Transport Facilities (12%)", "Transit and Shops Dense with Few Amenities (15%)", and "Safe but Activity Unsupportive (5%)". Country representation differed by type (e. g., U. S. disproportionally represented "Safe but Activity Unsupportive"). Compared to the Safe but Activity Unsupportive, two types showed greater odds of meeting PA guideline for walking outcome (High Walkable and Unsafe with Few Recreation Facilities, OR=2.26 (95% CI 1.18-4.31); Overall Activity Supportive, OR=1.90 (95% CI 1.13-3.21). Significant but smaller odds ratios were also found for total PA. Conclusions: Meaningful neighborhood patterns generalized across countries and explained practical differences in PA. These observational results support WHO/UN recommendations for programs and policies targeted to improve features of the neighborhood environment for PA.

  • 430.
    Adams, Nathalie
    et al.
    Linnaeus University, School of Business and Economics, Department of Marketing.
    Chyssler, Louise
    Linnaeus University, School of Business and Economics, Department of Marketing.
    Tourism in Mexico: More than Tacos and Tequila?: A Case Study on CSR Strategies of Swedish and Mexican Tour Operators in Mexico 2014Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    The purpose of this study is to explore whether tour operators work with CSR within their organizations in Mexico, and describe how they implement it as well as why they work with it. Furthermore, the paper will analyze similarities and differences between the Swedish and Mexican tour operator’s CSR strategies as well as the reasons for this. Lastly, recommendations will be made to the Mexican tour operators on how they can gain knowledge from Swedish tour operators on CSR strategies and the development of these.The theoretical framework contains descriptions of theories on strategy, competitive advantage, the CSR Pyramid, stakeholder theory as well as CSR in the context of developing countries, which are all relevant theories for the issue studied as well as for answering the research questions. The empirical findings that have been collected through interviews with two Swedish, and two Mexican tour operators address the respective tour operator’s work with CSR in Mexico.In the analysis the theoretical framework has been put in relation to the empirical evidence. The analysis consists of how and why CSR activities are implemented in the respective organization. It also addresses the difficulties tour operators from developed countries face when implementing CSR on destinations in developing countries.Lastly, our conclusions show that there are several ways of implementing CSR in developing countries, as well as different views on why taking social responsibility within the tourism industry is important. Moreover, the main reason for this divergence lies in different perspectives, which has also been shown to be a contributing factor to the challenges faced by Swedish tour operators in the context of a developing country.In the end of the thesis recommendations will be made to Mexican firms on how to develop, and implement CSR strategies more successfully as well as recommendations for further research within the field of CSR in developing countries.

  • 431.
    Adamsdotter, Annelie
    Linnaeus University, Faculty of Arts and Humanities, Department of Film and Literature.
    Drömvandrarens dotter2019Independent thesis Basic level (degree of Bachelor of Fine Arts), 20 HE creditsStudent thesis
    Abstract [sv]

    Ingen vet var hon kommer ifrån eller att hon snart ska spela huvudrollen i en uråldrig profetia; allra minst hon själv.

    17-åriga Amelia har aldrig passat in i Ljusets systraskap. Hon älskar spänning och äventyr, inte broderier och körsång. I flera år har hon sparat silvermynt från tjuvjaktsbyten för att börja om någon annanstans. Men så en natt träffar hon den mystiska Gabriel – vars sneda leende följer henne ända in i drömmen – och helt plötsligt förändras allt. Ingenting är längre säkert … ingenting förutom att världen som hon känner till den kommer att gå under.

  • 432.
    Adamska, Joanna
    et al.
    Växjö University, Faculty of Humanities and Social Sciences, School of Management and Economics.
    Karcz, Kamila
    Växjö University, Faculty of Humanities and Social Sciences, School of Management and Economics.
    Liu, Rongzhi
    Växjö University, Faculty of Humanities and Social Sciences, School of Management and Economics.
    How to survive as an expatriate in China2006Independent thesis Advanced level (degree of Master (One Year)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    The increase of foreign direct investment in China has resulted in the presence of a number of Western expatriates working in Sino–foreign joint ventures. These expatriate managers have to make things work in absolutely new settings. Therefore, without cross-cultural trainings, they may have very stressful experience in China. Understanding of the Chinese culture and Chinese society may ultimately save much frustration and money. With our thesis therefore we would like to explore how companies manage training processes before sending expatriates to China, and prepare them for further knowledge transfer to the employees in China. This has lead us to the following research question: “How do the Western companies manage process of sending expatriates to China?”

    The research is based on the experiences of three companies: IKEA, Texol Technical Solutions and NCR and demonstrates possible means that can be engaged by the companies to facilitate adjustment processes of their expatriates in China. The empirical data were gathered from interviews with managers from the mentioned companies. In order to analyze our empirical findings we present literature that was structured as follows: Training in the international context, training in the Chinese context and communication between expatriate and local employees. Both the literature review as well as our empirical data with analysis aspire to provide the reader with an in depth study of the importance of the selection of the right candidates and the provision of trainings, as it can help both to understand the unique Chinese cultural and business characteristics environment as well as effectively and efficiently to operate in China.

    In our conclusions we present our findings regarding the following issues: support for the expatriates; training of the Chinese employees and importance of communication. Based on our analysis we introduce our recommendations for the three companies, including: Selection of the right candidates, presence of action plans, motivation and incentives, trainings, contact with the company and other expatriates during the assignment and importance of repatriation.

  • 433.
    Adamsson, Philip
    et al.
    Linnaeus University, School of Business and Economics, Department of Management Accounting and Logistics.
    Petersson, Johannes
    Linnaeus University, School of Business and Economics, Department of Management Accounting and Logistics.
    Användarens roll vid prestationsmätning för miljö: En fallstudie på Växjö kommun2017Independent thesis Advanced level (degree of Master (One Year)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    Title: The user's role in Environmental Performance Measurement- A case study on Växjö municipality

    Background: Increased awareness of the environment in society, growing public pressure and more regulations have affected public organisation's efforts in the environmental field. The result of this effort is that environmental performance measurements have been implemented from the private sector so that public organisations can demonstrate improvements and make evaluations of their work on environmental issues. However, researchers argue that collecting information about performance is not enough, the information also needs to be used in the organisation. Therefore it became interesting to study how public sector managers use information from Environmental performance measurements and why the information is used.

    Purpose: The purpose of this study is to describe and analyse how managers at Växjö municipality use information from Environmental Performance Measurements and explain why the information is used. In addition, the study aims at providing improvement proposals that support Växjö municipality's work on Environmental Performance Measurement.

    Methods: This study is a qualitative case study with Växjö municipality as the case. In collecting data, qualitative interviews have been conducted, but data is also collected through internal documents, such as Växjö municipality's Environmental Program

    Results and conclusions: The study's results shows that managers at Växjö municipality mainly use information from Environmental Performance Measurements for internal purposes, although some managers are more likely to use information than others. The study's results also shows that the work on environmental Performance Measurement can be further developed.

  • 434.
    Adamsson, Philip
    et al.
    Linnaeus University, School of Business and Economics, Department of Management Accounting and Logistics.
    Petersson, Johannes
    Linnaeus University, School of Business and Economics, Department of Management Accounting and Logistics.
    Andersson, Gabriel
    Linnaeus University, School of Business and Economics, Department of Management Accounting and Logistics.
    Belöningssystem och motivation: En flerfallsstudie på företag inom byggbranschen2016Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Abstract

    Title: Reward system and motivation – A multi-case study in the construction industry

    Authors: Philip Adamsson, Gabriel Andersson, Johannes Petersson

    Examiner: Elin Funck

    Supervisor: Natalia Semenova

    Background and problem: A reward system is an instrument that is widely used, where management with help of a functional reward system can get a desired behavior from an employee. How a reward system is designed differs between sectors. The construction industry is a sector bordered by conflicts of interest between employers and employees. Is there a match between the employer's intention with reward systems and employee’s perception of the reward system? There are multiple rewards that can provide a desired behavior, but what is it that really motivate employees in the construction industry.

    Purpose: The purpose of this study is to describe how the reward system is designed in the construction industry. Furthermore, the purpose of the study is to see if the employer's intentions and the employee's perception of the reward system is consistent. The study also intends to describe why, or why not employees feel that the reward system motivates them.

    Methods: We conducted a multi-case study of Svensk Vattenbilningsteknik AB and TECAB Ytskyddsprodukter AB. Both companies are active in the construction industry. Empirical material were obtained through semi-structured interviews. The study had a deductive research approach.

    Conclusion: We can conclude that employers should focus on the purpose of their reward system to design a functional system. According to the study, a reward system should contain a combination of financial and non-financial rewards. Finally, a financial bonus should be a part of a construction company´s reward system, because it increases employee motivation and satisfaction.

  • 435.
    Adamsson, Sandra
    et al.
    Linnaeus University, School of Business and Economics, Department of Organisation and Entrepreneurship.
    Lundell, Sophie
    Linnaeus University, School of Business and Economics, Department of Organisation and Entrepreneurship.
    Creating a win-win-win-win situation: En fallstudie av den sociala entreprenörens motivation2013Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [sv]

    Bakgrund: Socialt företagande utmärks av entreprenörens förmåga att identifiera samhällsproblem och tillmötesgå de sociala behoven i samhället. Det finns olika definitioner av socialt entreprenörskap, och dessa antyder att de styrande drivkrafterna skiljer sig ifrån de i traditionellt entreprenörskap. De motivationsfaktorer som den sociala entreprenören har skulle kunna återspeglas i hur verksamheten bedrivs och hur organisationens grundtankar förmedlas ut i företaget. Vidare skulle detta kunna ha en påverkan i strävan efter företagets uppsatta mål, vare sig deär socialt, miljömässigt eller ekonomiskt motiverade.

    Problemformulering: Vad finns det för drivkrafter hos en social entreprenör samt hur genomsyras det i företaget?Syfte:Syftet med uppsatsen är att genom fallstudie skapa ökad förståelse för den sociala entreprenören samt hur den motivation som finns visar sig iverksamheten.

    Metod: För uppsatsen har en kvalitativ ansats valts,och baseras på en fallstudie av ett företag vars verksamhet utgår ifrån socialt entreprenörskap. Data har samlats in via ett abduktivt tillvägagångssätt, genom semi-strukturerade intervjuer, observationer och teoretisk insamling.

    Slutsats: Uppsatsen påvisar de drivkrafter som finns hos den sociala entreprenören. Exempelvis att det primära målet är att uppnå en positiv social-och miljömässig påverkan i samhället, snarare än att generera en ekonomisk vinst. Andra drivkrafter är samtidigt att motivera och utbilda personalen inom medvetenhet om hållbarhet, säkerhet och kvalitet.

  • 436.
    Adamsson, Stina
    Linnaeus University, Faculty of Technology, Department of Informatics.
    Kommunikationskanaler vid intern nyhetsspridning: En fallstudie om hur kommunikationskanaler påverkar den upplevda kommunikationseffektiviteten vid nyhetsspridning2019Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Communication is an important function within organizations and the ways of communicating have developed rapidly due to technological development, which can make it difficult to know which communication channel that is best to use in different situations. This report is based on a case study were the perceived communication efficiency tended to vary depending on which communication channel that was used. Previous research shows how the choice of communication channels can affect the communication efficiency, however, it does not show this from the perspective of news as an information type. Therefore, it was considered interesting to study how different communication channels affect the communication efficiency in terms of news distribution.

     

    The aim of this study was to illustrate and describe how communication channels affect the perceived communication efficiency when the information that is transferred consists of news. To achieve this, the following research question would be answered:

     

    • What advantages and disadvantages do employees experience with communication channels regarding the communication efficiency for news distribution in a large national company?

     

    Theories that have been applied in the study are Media Richness Theory and Osgood and Schramms circular communication model. Theories have been used to explain how news distribution takes place in the case company and to illustrate and possibly explain the problems that the company experience with news distribution.

     

    Data was collected by applying a qualitative method in which semi-structured interviews have been used. The result shows that respondents experience both advantages and disadvantages with all the communication channels and that the perceived communication efficiency tended to vary depending on which kind of news. When the result was set against the research question and the theoretical framework, advantages and disadvantages that were experienced, turned out to be depending on if the news were routine or non-routine and how it was matched with a rich or poor communication channel, which Media Richness Theory also declare. 

     

    The conclusion of this study shows that news distribution through face to face and telephone enables direct interaction and transmission of emotions, however, emotions are not transmitted as well through telephone as face to face. The many signals can also be experienced as overwhelmingly. E-mail, intranet and signboard are effective in terms of time and are not as depending on time and space. In addition, the possibility of direct interaction and transmission of feelings is limited. The result indicates that advantages and disadvantages with the communication channels seems to be linked to whether the channel is perceived as suitable to transfer different kinds of news. Rich communication channels are perceived to be effective for transmitting non-routine news and poor channels are perceived to be effective for transmitting routine news.

  • 437.
    Adappan Ramu, Sasikala
    et al.
    Linnaeus University, Faculty of Technology, Department of Informatics.
    Narasingam Kuppusamy, Venkatesh
    Linnaeus University, Faculty of Technology, Department of Informatics.
    Exploring knowledge sharing in the Requirement Engineering phase of globally distributed Information Systems development: Perceived challenges and suggestions for improvement2016Independent thesis Advanced level (degree of Master (One Year)), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    The Master thesis explores the knowledge sharing that takes place during the requirement engineering phase of globally distributed information systems development. In recent years, due to globalization, information systems development activities have become increasingly distributed across different geographical locations. Requirement engineering is an important and knowledge intensive phase in the development of information systems. Requirement engineering is the process of identifying, analyzing, documenting, validating and managing the requirements of a system. Effective and efficient knowledge sharing during the requirement engineering is vital for the successful development of information systems. However, the global distribution of the stakeholders has affected knowledge sharing during requirement engineering in various ways making it more challenging.

     

    Drawing on the theories of knowledge sharing within the field of information systems, this interpretive research study aims at exploring stakeholders’ perceptions about the challenges met during the knowledge sharing in requirement engineering phase of globally distributed information systems development projects. More specifically, this Master thesis explores the perceived challenges and generates a list of suggestions to overcome the challenges by conducting qualitative semi-structured interviews among the key stakeholders, both customers and business analysts.

     

    The findings indicate that the knowledge sharing is influenced by challenges such as cultural differences, language barriers, communication issues, coordination issues arising from multiple stakeholders, time difference and difficulty in sharing tacit knowledge in the globally distributed settings. Participants’ suggestions for overcoming these challenges include cultural trainings, kick off meetings, language trainings, use of translator, face-to-face communication and interaction, video conferencing, scheduling important meetings in the common suitable timings, identification of the main stakeholders, having a mediator and making close observations with face-to-face interactions.

     

     

    Keywords:  Information Systems, Information Systems Development, Requirement Engineering, Knowledge Sharing, Global Distribution, Outsourcing

     

     

  • 438.
    Adbo, Karina
    Linnaeus University, Faculty of Social Sciences, Department of Education.
    Hur ska vi skapa struktur och logik i kemiundervisningen?2014In: LMNT-nytt, ISSN 1402-0041, no 1, p. 28-32Article in journal (Other (popular science, discussion, etc.))
  • 439.
    Adbo, Karina
    Linnaeus University, Faculty of Science and Engineering, School of Natural Sciences.
    Relationships between models used for teaching chemistry and those expressed by students2012Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    This thesis is focused upon chemistry as a school subject and students' interpretations and use of formally introduced teaching models. To explore students' developing repertoire of chemical models, a longitudinal interview study was undertaken spanning the first year of upper secondary school chemistry. Matter in its different states was selected as the target framework for this study. The results presented are derived from both generalisations of groups of students as well as a case study describing an individual learner's interpretation of formal content. The results obtained demonstrated that the formal teaching models provided to the students included in this study were not sufficient to afford them a coherent framework of matter in its different states or for chemical bonding. Instead, students' expressed models of matter and phase change were to a high degree dependent on electron movement (Paper I), anthropomorphism (Paper II) and, for one student, a mechanistic approach based on small particles and gravitation (Paper III). The results from this study place focus on the importance of learners' prior learning (previous experiences) and the need to develop a coherent framework of formal teaching models for the nature of matter and phase change.

  • 440.
    Adbo, Karina
    et al.
    University of Kalmar, School of Pure and Applied Natural Sciences.
    Andersson, Håkan S.
    University of Kalmar, School of Pure and Applied Natural Sciences.
    Ankarloo, Jonas
    University of Kalmar, School of Pure and Applied Natural Sciences.
    Karlsson, Jesper G.
    University of Kalmar, School of Pure and Applied Natural Sciences.
    Norell, M C
    Olofsson, Linus
    University of Kalmar, School of Pure and Applied Natural Sciences.
    Svenson, Johan
    University of Kalmar, School of Pure and Applied Natural Sciences.
    Örtegren, U
    Nicholls, Ian A.
    University of Kalmar, School of Pure and Applied Natural Sciences.
    Enantioselective synthetic receptors for Tröger’s base1999In: Bioorganic Chemistry, Vol. 27, no 5, p. 363-371Article in journal (Refereed)
  • 441.
    Adbo, Karina
    et al.
    University of Kalmar, School of Pure and Applied Natural Sciences.
    Nicholls, Ian Alan
    University of Kalmar, School of Pure and Applied Natural Sciences.
    Enantioselective SPE on Tröger’s base molecularly imprinted polymers2001Conference paper (Refereed)
  • 442.
    Adbo, Karina
    et al.
    University of Kalmar, School of Pure and Applied Natural Sciences.
    Nicholls, Ian Alan
    University of Kalmar, School of Pure and Applied Natural Sciences.
    Study of the kinetics of enantioselective solid-phase extraction on Tröger’s base molecularly imprinted polymers2001In: Analytica Chimica Acta, Vol. 435, p. 115-120Article in journal (Refereed)
  • 443.
    Adbo, Karina
    et al.
    University of Kalmar, School of Pure and Applied Natural Sciences.
    Rosengren-Holmberg, Jenny
    University of Kalmar, School of Pure and Applied Natural Sciences.
    Nicholls, Ian Alan
    University of Kalmar, School of Pure and Applied Natural Sciences.
    Kinetics of enantioselective solid-phase extraction of Tröger’s base molecularly imprinted polymers2000Conference paper (Refereed)
  • 444.
    Adbo, Karina
    et al.
    Linnaeus University, Faculty of Science and Engineering, School of Natural Sciences.
    Taber, Keith
    Developing a way to view chemistry: a case study of one Swedish student’s rich conceptualisations to make sense of upper high school chemistryManuscript (preprint) (Other academic)
  • 445.
    Adbo, Karina
    et al.
    Linnaeus University, Faculty of Social Sciences, Department of Education.
    Taber, Keith
    University of Cambridge.
    Developing an Understanding of Chemistry: A case study of one Swedish student's rich conceptualisation for making sense of upper secondary school chemistry2014In: International Journal of Science Education, ISSN 0950-0693, E-ISSN 1464-5289, Vol. 36, no 7, p. 1107-1136Article in journal (Refereed)
    Abstract [en]

    In this paper, we report a case study of a 16-year-old Swedish upper secondary student's developing understanding of key concept areas studied in his upper secondary school chemistry course. This study illustrates how the thinking of an individual learner, Jesper, evolves over a school year in response to formal instruction in a particular educational context. Jesper presented a range of ideas, some of which matched intended teaching whilst others were quite inconsistent with canonical chemistry. Of particular interest, research data suggest that his initial alternative conceptions influenced his thinking about subsequent teaching of chemistry subject matter, illustrating how students' alternative conceptions interact with formal instruction. Our findings support the claims of some researchers that alternative conceptions may be stable and tenacious in the context of instruction. Jesper's rich conceptualisation of matter at submicroscopic scales drew upon intuitions about the world that led to teaching being misinterpreted to develop further alternative conceptions. Yet his intuitive thinking also offered clear potential links with canonical scientific concepts that could have been harnessed to channel his developing thinking. These findings support the argument that identifying students' intuitive thinking and how it develops in different instructional contexts can support the development of more effective science pedagogy.

  • 446.
    Adbo, Karina
    et al.
    University of Kalmar, School of Pure and Applied Natural Sciences.
    Taber, Keith
    Learners' Mental Models of the Particle Nature of Matter: A study of 16-year-old Swedish science students2009In: International Journal of Science Education, ISSN 0950-0693, E-ISSN 1464-5289, Vol. 31, no 6, p. 757-786Article in journal (Refereed)
    Abstract [en]

    The results presented here derive from a longitudinal study of Swedish upper secondary science students' (16-19 years of age) developing understanding of key chemical concepts. The informants were 18 students from two different schools. The aim of the present study was to investigate the mental models of matter at the particulate level that learners develop. Data were collected using semi-structured interviews based around the students' own drawings of the atom, and of solids, liquids, and gases. The interview transcripts were analysed to identify patterns in the data that offer insight into aspects of student understanding. The findings are discussed in the specific curriculum context in Swedish schools. Results indicate that the teaching model of the atom (derived from Bohr's model) commonly presented by teachers and textbook authors in Sweden gives the students an image of a disproportionately large and immobile nucleus, emphasises a planetary model of the atom and gives rise to a chain of logic leading to immobility in the solid state and molecular breakdown during phase transitions. The findings indicate that changes in teaching approaches are required to better support learners in developing mental models that reflect the intended target knowledge.

  • 447.
    Adbo, Karina
    et al.
    Linnaeus University, Faculty of Health and Life Sciences, Department of Biology and Environmental Science.
    Vidal Carulla, Clara
    Linnaeus University, Faculty of Health and Life Sciences, Department of Biology and Environmental Science.
    Designing play-based learning chemistry activities in the preschool environment2019In: Chemistry Education Research and Practice, ISSN 1756-1108, E-ISSN 1756-1108, Vol. 20, no 3, p. 542-553Article in journal (Refereed)
    Abstract [en]

    This study focuses on the design of play-based learning activities for chemistry in preschool. Viewing chemistry as a part of our past and present culture instead of as a subject, provides the backdrop for a more holistic approach to chemistry within this specific environment. A cultural-historical perspective, together with scaffolding, emergent science skills and sustained shared thinking, made up the framework for the design of the learning activities. Results show that when scaffolding and emergent science skills are used within the design, they provide good support for both the content and the teacher in the actual learning situation. Working with scaffolding was also beneficial for professional development. However, for a progressive and inclusive activity design, it is essential to take into account aspects of the immediate environment and methods for direct evaluation.

  • 448. Adcock, Edward P.
    et al.
    Varlamoff, Marie-Thérèse
    Kremp, Virginie
    IFLA-ina nacela za skrb i rukovanje knjiznicnom gradom: IFLA principles for the care and handling of library material2003Other (Other (popular science, discussion, etc.))
  • 449.
    Addassi, Mouadh
    et al.
    Technical University of Denmark, Denmark.
    Johannesson, Björn
    Linnaeus University, Faculty of Technology, Department of Building Technology.
    Reactive mass transport in concrete including for gaseous constituents using a two-phase moisture transport approach2020In: Construction and Building Materials, ISSN 0950-0618, E-ISSN 1879-0526, Vol. 232, p. 1-14, article id 117148Article in journal (Refereed)
    Abstract [en]

    This article presents the further development of a tool for multi-phase reactive mass transport modelingfor durability estimation of cement-based materials, by the addition of the gas phase, adopting a trulyseparate two-phase moisture transport approach. The governing system of equations are based on phys-ically sound hybrid mixture based version of the Poisson-Nernst-Planck system of equations includinggaseous transport in the air-filled space, ionic transport in the liquid phase, electro-migration of ionicspecies, a two-phase moisture transport model, and sorption. The addition of the gas phase and thetwo-phase moisture description enables the user of the model to investigate individual and combinedeffects of different degradation processes in unsaturated systems. The altering of hydrated cement underthree different environments were studied representing an accelerated carbonation environment, a sub-merged marine environment and a cyclic drying-wetting zone in a marine environment, to illustratesome of the model’s capabilities.

  • 450.
    Addassi, Mouadh
    et al.
    Technical University of Denmark, Denmark.
    Johannesson, Björn
    Linnaeus University, Faculty of Technology, Department of Building Technology.
    Wadsö, Lars
    Lund University.
    Inverse analyses of effective diffusion parameters relevant for a two-phase moisture model of cementitious materials2018In: Cement and Concrete Research, ISSN 0008-8846, E-ISSN 1873-3948, Vol. 106, p. 117-129Article in journal (Refereed)
    Abstract [en]

    Here we present an inverse analyses approach to determining the two-phase moisture transport properties re-levant to concrete durability modeling. The purposed moisture transport model was based on a continuumapproach with two truly separate equations for the liquid and gas phase being connected by the sorption ki-netics. The moisture properties of ten binder-systems containingfly ash, calcined clay, burnt shale and graymicro-filler, were investigated experimentally. The experiments used were, (i) sorption test (moisturefixation),(ii) cup test in two different relative humidity intervals, (iii) drying test, and, (iv) capillary suction test. Masschange over time, as obtained from the drying test, the two different cup test intervals and the capillary suctiontest, was used to obtain the effective diffusion parameters using the proposed inverse analyses approach. Themoisture properties obtained with the proposed inverse analyses method provide a good description of the testperiod for the ten different binder-systems.

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