Arbetet med undersökningar bland annat genom laborationer finns idag med som ett obligatoriskt moment i läroplanen. Både i det centrala innehållet och i kunskapskraven poängteras betydelsen av att eleverna ska få möjlighet att arbeta praktiskt för att utveckla och visa sina kunskaper. Med utgångspunkt i detta väcktes intresset att undersöka arbetet med laborationer ute i verksamheten. Denna studie utgår ifrån ett lärarperspektiv och syftar till att beskriva vilka uppfattningar lärare har kring vad laborationer tillför i deras undervisning, hur elevernas lärande påverkas och vilka utmaningar de ställs inför genom detta arbetssätt. I studien deltar fem lärare med behörighet i de naturvetenskapliga ämnena och data samlas in med hjälp av kvalitativa intervjuer. Studiens resultat visar att lärarna har en relativt enad syn på laborationernas roll i undervisningen. De nämner att laborationer skapar intresse och motivation samtidigt som det skapas en koppling mellan det teoretiska och praktiska innehållet. Elevernas lärande gynnas också eftersom laborationer enligt lärarna passar de flesta elever och även hjälper dem att minnas vad de har arbetat med. De utmaningar lärarna ser med laborationer handlar om brist på material, att det är tidskrävande och att det kan vara svårt att anpassa innehåll och utformning till elevgruppen.

Abstract  We've investigated the effects of outdoor education, specifically how it impacts students' learning and attitudes, along with didactic choices worth considering from the teachers' perspective.  There are two main reasons behind our choice of research topics. Firstly, according to PISA results, Swedish science knowledge has been trending downwards since the early 2000s. Simultaneously, engagement and motivation among students have been following a similar trend.  Secondly, generational environmental amnesia, as described by Kahn (2017), has been diminishing people's connection with nature, slowly altering individuals' views of nature and its importance.  We intend to draw a conclusion regarding how increased use of outdoor education improves students' learning and leads to a more engaging and motivating science education. Can an increased use of outdoor education counteract environmental generational amnesia?  We've compiled information from trustworthy and mostly peer-reviewed sources to build this knowledge review. Our sources serve as the foundation of knowledge for our conclusions.  However, we found a gap in research regarding the challenges outdoor education faces. While much research has been done on how and why it's a valuable pedagogy, not much has been said about barriers limiting outdoor education and how to counteract them.  Our key message is that outdoor education is a valuable pedagogy for students as well as teachers. It leads to increased learning, higher motivation, more engagement, and is a way to develop nature literacy, counteracting the furtherance of environmental generational amnesia.

In this thesis, the recent development step of magnetron sputtering, termed high power impulse magnetron sputtering (HiPIMS) has been studied. Compared to conventional magnetron sputtering HiPIMS provides a higher plasma density which can ionise the sputtered material. The beneficial influence of the coating properties due to this ionisation has been extensively shown in academic publications. Here, industrial conditions, i.e. no substrate heating and high vacuum conditions have been used during the studies, of which one was performed in an industrial deposition system. For eight metallic targets, films were deposited with HiPIMS and conventional sputtering. The films were evaluated by Rutherford back scattering analysis, scanning electron microscopy, and profilometry. It was found that the density of the HiPIMS grown films exhibited a statistically significant higher density of approximately 5-15% in comparison to films deposited using DCMS under identical conditions. A global plasma model was employed to evaluate the degree of ionisation for some of the target materials, and process conditions used in the study. Conformity between density increase and degree of ionisation as assessed by the plasma model was confirmed. The influence of using HiPIMS during reactive sputtering of TiC was also studied. A metallic Ti target was sputtered in a gas mixture of Ar and C2H2. The coatings were evaluated by X-ray photoelectron spectroscopy, X-ray diffraction, scanning electron microscopy, 4 point probe resistivity measurements, and nanoindentation. The coatings were found to be nanocomposite TiC/a-C:H. For the HiPIMS process the transition zone between metallic and compound target states was found to be significantly expanded over a wide reactive gas flow range. The implications of choice of deposition method for coating composition, chemical structure, as well as electrical and mechanical properties were evaluated for DCMS and HiPIMS. The process behaviour was suggested to be due to the pulsed nature of the HiPIMS, the high plasma density, and ion content of the particles reaching the substrate.

This thesis describes work to investigate the potential of using an ordinary mobile phone to perform chemical sensing by colorimetric analysis of reflected light. The wide availability and familiarity of mobile phones make them excellent devices for aiding consumers in making on site tests in their everyday lives. A major part of the work has been the development of the necessary software to be able to use a standard mobile phone to study diffuse reflection with the screen as illumination source and the front view camera for collection of spectral information. Java Micro Edition was used to control the hardware resources of the phone. The NetBeans 6.5 platform facilitated the design, development, testing and implementation of a dedicated Mobile Information Device  applet for performing the necessary tasks associated with controlling the screen light and recording the reflected light intensities. MATLAB was employed to extract spectral information from the recorded images. Initially, tests with a virtual sample having areas with different colors were performed. Optimization of the alignment of the sample and the distance between the camera and the sample were carried out and the influence of ambient light was investigated. The lateral resolution of the images enables optical readout of sensor arrays as well as arrays for diagnostics. The potential of using the technique for direct measurement of properties related to the quality of drinking water, food and beverages was also investigated. Liquid samples were prepared in deionized water. Colored compounds such as iron(III)chloride and humic acid in the concentration range 2-10 mg/l were classified from their reflected intensities. Colorless arsenic(III) was analyzed by its bleaching reaction with iodine/starch. An alternative arsenic detection method based on measurement of discoloration of iron containing sand was demonstrated. We have also demonstrated that mobile phones can be used for qualitative analysis of food and drink, such as cold drinks, meat,  vegetables and milk in terms of general food quality.

Wide band gap semiconductors, Zinc Oxide (ZnO), Gallium Nitride (GaN) and Silicon Carbide (SiC) have been emerged to be the most promising semiconductors for future applications in electronic, optoelectronic and power devices. They offer incredible advantages in terms of their optical properties, DC and microwave frequencies power handling capability, piezoelectric properties in building electromechanical coupled sensors and transducers, biosensors and bright light emission. For producing high quality devices, thermal treatment always plays an important role in improving material structural quality which results in improved electrical and optical properties. Similarly good quality of metal–semiconductor interface, sensitive to the semiconductor surface, is always required. In this thesis we report the study of the interface states density for Pd/Ti/Au Schottky contacts on the free-standing GaN and post fabrication annealing effects on the electrical and optical properties of ZnO/Si hetero-junction diodes. The determination of interface states density (NSS) distribution within the band gap would help in understanding the processes dominating the electrical behavior of the metal–semiconductor contacts. The study of annealing effects on photoluminescence, rectification and ideality factor of ZnO/Si hetero-junction diodes are helpful for optimization and realization to build up the confidence to commercialize devices for lightening. A comparison of device performance between the physical simulations and measured device characteristics has also been carried out for pd/ZnO Schottky diode to understand the behavior of the devices. This research work not only teaches the effective way of device fabrication, but also obtains some beneficial results in aspects of their optical and electrical properties, which builds theoretical and experimental foundation for much better and broader applications of wide band gap semiconductor devices.

Seven wetlands, constructed on agricultural land in the south of Sweden, were investigated with respect to phosphorus (P) retention. The overall aim was to increase the understanding of P retention and find possible explanations for the variations in retention that have been observed in previous studies. This was done by i) investigating P retention in wetlands receiving various water and P loads, ii) investigating the effect of variations in water flow on P transport, iii) comparing how well retention estimates based on water quality data agreed with measurements of the amount of P accumulated in the sediment. Results showed that P retention was positive in all wetlands, but it was variable (1–58 kg ha-1 yr-1) and months with negative retention were observed in nearly all wetlands. Such  monthly negative retention coincided with i) high flow periods, when particulate P was either flushed straight through the wetlands or resuspended from the bottoms, and ii) warm low flow periods, in which case dissolved P was probably released from wetland sediments due to anoxic conditions. The results from the two methods for estimating P retention differed. Based on water quality data, the total P load during four years was 65 kg ha-1 and the mean P retention 2.8 kg ha-1 yr-1, or 17% of the total P load. In contrast, the amount of P accumulated in the inlet zone alone amounted to 78% of the P load, and the P content in the upper sediment of the whole wetland area exceeded the P load with a factor four. This discrepancy showed the need to add studies of sediment accumulation to inflow-outflow estimates for an improved understanding of wetland P retention.

In this thesis work two very similar processes have been studied both involving excitations of particles during recombination of exciton complexes in quantum dots, reducing the energy of the emitted photon. Different exciton complexes are defined according to the number of electrons and holes in the quantum dot upon recombination. The neutral exciton complexes with one electron and one hole (X–) and two electrons and two (X+) holes respectively are referred to as the exciton andthe biexciton. Accordingly the charged exciton complexes consisting of two electrons and one hole (X–) and one electron and two holes (X+), respectively, are referred to as negatively- and positively charged excitons, respectively. Whenever another particle is excited during the recombination of one electron-hole pair within these complexes, the result is a weak satellite peak, spectrally redshifted with respect to the main emission peaks related to the exciton complex. In the first part of this thesis work, described in the first two papers, the exciton-LO-phonon interaction is studied with a weak redshifted satellite peak as the signature, referred to as a phonon replica. The intensity ratio between the replicas and the corresponding main emission were determined from the obtained microphotoluminescencespectra. It was found that this ratio was significantly weaker for the positively charged exciton X+ compared to the neutral exciton, X, and the negatively charged exciton, X–. This experimentally obtained result was further supported by computations. Interestingly, the computations revealed that despite that X+ displays the weakest phonon replica among the investigated complexes, it possesses the strongest Fröhlich coupling to phonons in the lattice before recombination. In addition, the spectral broadening of the phonon replicas compared to the main emission is discussed. Also, the origin of the exciton-LO-phonon coupling is concluded to be from the QD itself, based on a comparison between quantum dots with different barriers. In the last paper an additional weak redshifted satellite peak in the recombination spectra is studied. The intensity of this weak satellite peak is correlated to the peak intensity of the positively charged exciton, X+, main emission peak. In addition to this photoluminescence excitation experiments, magnetic field measurement and calculations further support our interpretation that the satellite peak is related to the shake-up of the ground-state hole in the QD that is not involved in the optical recombination. This hole is thus excited by Coulomb interaction to an excited state yielding a photon energy reduced with the difference between the ground-state and the excited state of the spectator hole.

Den här studiens bakgrund grundades i att flera studier har visat en växande skillnad gällande attityder till naturvetenskap och teknik mellan pojkar och flickor. Flickor uppvisar en tendens att vara mer skeptiska till ämnena än vad pojkar är. Funderingar växte fram om skillnader gick att finna även hos yngre elever. Syftet var att undersöka hur yngre elever i årskurs 3 ser på NO och teknik i skolan. Fokus lades på elevernas intresse gentemot ämnena både som skolämnen och som framtida yrken. Metoderna som användes i studien var en enkät, som genomfördes med 89 stycken elever, samt intervjuer med 12 stycken elever från tre olika skolor. Sammanfattningsvis visade studien att elever i årskurs 3 hade positiv inställning till NO och teknik samt fann ämnena intressanta. Studien visar också att vissa skillnader gick att finna mellan flickors och pojkars tankar kring framtida yrken inom de naturvetenskapliga ämnena och teknik.

Denna litteraturstudie undersöker hur lärare, enligt tidigare forskning, skulle kunna arbeta med naturvetenskapligt språk samt vilken betydelse ett arbetssätt som lyfter språket kan ha för elevers lärande av naturvetenskap. Detta är en systematisk litteraturstudie där relevant forskning har sökts via databaser och en tidsskrift för att noggrant dokumenteras. NorDiNa är den tidskrift som har bidragit med mest material till denna systematiska litteraturstudie, men även databasen ERIC och Högskolan Dalarnas databas Summon har genomsöks och bidragit med forskningsrapporter. Resultatet visar att det finns flera metoder som kan användas för att stödja elevers lärande av naturvetenskapliga begrepp. Läraren har en viktig roll i den naturvtenskapliga utbildningen och behöver vara ansvarstagande och förberedd inför de utmaningar som kan dyka upp, detta för att kunna bemöta och hjälpa elever på bästa sätt. Eleverna behöver stöttning i mötet med det naturvtenskapliga språket och hjälp för att lära sig och förstå det. Språket har visats i studien vara en viktig komponent för att förstå naturvetenskapen både i och utanför skolan. Sammanfattningsvis så behöver lärare arbeta med det naturvetenskapliga språket utifrån varierande arbetsmetoder som väcker intresse för elevernas fortsatta utveckling inom det naturvetenskapliga språket och ämnet.

Elevers resultat inom naturvetenskap fortsätter attförsämras. Lärares undervisning har granskats och det harfastställts att den naturvetenskapliga undervisningen i svenska skolan är bristfällig. Denna litteraturstudies områdeär utomhuspedagogik kopplat till de naturvetenskapligaämnena biologi, kemi och fysik. Syftet med litteraturstudien är att undersöka vad tidigare forskning tar upp om detutomhuspedagogiska arbetssättet, samt om vilka erfarenheter verksamma individer inom skolan har gällande den utomhuspedagogiska undervisningen. Frågeställningen vi utgått från är: Vilka möjligheter och hinder finns det med det utomhuspedagogiska arbetssättet för elever och lärare inom den naturvetenskapliga undervisningen? Vi har använt oss av metoden systematisk litteraturstudie för att undersöka relevant forskning inom det valda området. De viktigaste resultaten visar att det finns både möjligheter och hinder med utomhuspedagogik i den naturvetenskapligaundervisningen. Större delen av forskningen i detta arbete pekar på att utomhuspedagogik är ett arbetssätt som gynnar elevers lärande inom naturvetenskap. Vidare forskning bör innefatta elevers erfarenheter och åsikter om hur deras lärande påverkas av det utomhuspedagogiska arbetssättet.