This thesis concerns synthesis and characterization of carbon-based materials and theinvestigation of the possible use, of a selection of these materials, in biomedicalapplications. Protein adsorption and blood plasma tests were used for this purposeutilizing a surface sensitive technique called spectroscopic ellipsometry. The materials were synthesized by physical vapor deposition and characterizedregarding microstructure, mechanical properties and optical properties. The ternaries BC-N and Si-C-N as well as carbon and carbon nitrides (CNx) of different microstructureshave been examined. In the B-C-N work, the intention was to investigate the possibilityto combine the two materials CNx and BN, interesting on their own regarding highhardness and extreme elasticity, to produce a material with even better properties.Theoretical calculations were performed to elucidate the different element substitutionsand defect arrangements in the basal planes promoting curvature in the fullerene-likemicrostructure. The Si-C-N ternary was investigated with the consideration of finding away to control the surface energy for certain applications. Amorphous carbon and threemicrostructures of CNx were analyzed by spectroscopic ellipsometry in the UV-VIS-NIRand IR spectral ranges in order to get further insight into the bonding structure of thematerial. In the second part of this work focus was held on studies of macromolecularinteractions on silicon, carbon and CNx film surfaces using ellipsometry. One purposewas to find relevance (or not) for these materials in biological environments. Materials for bone replacement used today, e.g. stainless steel, cobalt-chromium alloys andtitanium alloys suffer from corrosion in body fluids, generation of wear particles inarticulating systems, infections and blood coagulation and cellular damage leading toimpaired functionality and ultimately to implant failure. Artificial heart valves made ofpyrolytic carbon are used today, with friction and wear problems. Thus, there is still aneed to improve biomaterials. The aim of the fourth paper was to investigate theinteraction between carbon-based materials and proteins. Therefore, amorphous carbon(a-C), amorphous (a), graphitic (g) and fullerene-like (FL) CNx thin films were exposedto human serum albumin and blood plasma and the amount of protein was measured insitu using spectroscopic ellipsometry. Surface located and accessible proteins after blood plasma incubations were eventually identified through incubations in antibody solutions. Antibody exposures gave indications of surface response to blood coagulation,complement activation and clotting. The a-C and FL-CNx films might according to theresults have a future in soft tissue applications due to the low immuno-activity, whereasthe g-CNx film possibly might be a candidate for bone replacement applications. "Layered" structures of fibrinogen, a fibrous but soft protein involved in manyprocesses in our body, were grown in situ and dynamically monitored by ellipsometry inorder to understand the adsorption process and molecule arrangement onto a siliconsurface. In the last paper of this thesis, the effects of ion concentration and proteinconcentration on the refractive index of water-based solutions used in in situ ellipsometrymeasurements were demonstrated and spectral refractive index data for water solutionswith different ionic strengths and protein concentrations have been provided.

¨This Thesis treats the growth and characterization of ternary transition metal nitride thin films. The aim is to probe deep into the Ti-Al-N system and to explore novel Sc-Al-N compounds. Thin films were epitaxially grown by reactive dual magnetron sputtering from elemental targets onto single-crystal substrates. Ion beam analyses were used for compositional analysis and depth profiling. Different X-ray diffraction techniques were employed, ex situ using Cu radiation and in situ during deposition using synchrotron radiation, to achieve information about phases, texture, and thickness of films, and to follow roughness evolution of layers during and after growth. Transmission electron microscopy was used for overview and lattice imaging, and to obtain lattice structure information by electron diffraction. In the Sc-Al-N system, the perovskite Sc3AlN was for the first time synthesized as a thin film and in single phase, with a unit cell of 4.40 Å. The hardness was found to be 14.2 GPa, the elastic modulus 21 GPa, and the room temperature resistivity 41.2 μΩcm. Cubic solid solutions of Sc1-xAlxN can be synthesized with AlN molar fraction up to ~60%. Higher AlN contents yield three different epitaxial relations to ScN(111), namely, #1 Sc1-xAlxN(0001) || ScN(111) with Sc1-xAlxN[11210] || ScN[110], #2 Sc1-xAlxN(1011) || ScN(110) with Sc1-xAlxN[1210] || ScN[110], and #3 Sc1-xAlxN(1011) || ScN(113). An in situ deposition and annealing study of cubic Sc0.57Al0.43N films showed volume induced phase separation into ScN and wurtzite structure AlN, via nucleation and growth at the domain boundaries. The first indications for phase separation are visible at 1000 °C, and the topotaxial relationship between the binaries after phase separation is AlN(0001) || ScN(001) and AlN<01ɸ10> || ScN <1ɸ10>. This is compared with Ti1-xAlxN, for which an electronic structure driving force leads to spinodal decomposition into isostructural TiN and AlN already at 800 °C. First principles calculations explain the results on a fundamental physics level. Up to ~22% ScN can under the employed deposition conditions be dissolved into wurtzite Sc1-xAlxN films, while retaining a single-crystal structure and with lattice parameters matching calculated values. In the Ti-Al-N system, the Ti2AlN phase was synthesized epitaxially by solid state reaction during interdiffusion between sequentially deposited layers of AlN(0001) and Ti(0001). When annealing the sample, N and Al diffused into the Ti layer, forming Ti3AlN(111) at 400 ºC and Ti2AlN(0001) at 500 ºC. The Ti2AlN formation temperature is 175 ºC lower than earlier reported results. Another way of forming Ti2AlN phase is by depositing understoichiometric TiNx at 800 °C onto Al2O3(0001). An epitaxial Ti2Al(O,N) (0001) oxynitride forms close to the interface between film and substrate through a solid state reaction. Ti4AlN3 was, however, not possible to synthesize when depositing films with a Ti:Al:N ratio of 4:1:3 due to competing reactions. A substrate temperature of 600 ºC yielded an irregularly stacked Tin+1AlNn layered structure because of the low mobility of Al ad-atoms. An increased temperature led to Al deficiency due to outdiffusion of Al atoms, and formation of the Ti2AlN phase and a Ti1-xAlxN cubic solid solution.

This thesis treats surface engineering with the purpose of improved quality of optical and electricalconnectors with a focus on electroplated and magnetron sputtered materials. In electroforming of tools formanufacturing optical connectors, the influence of ultrasonic agitation on intrinsic stresses and fillingproperties of electroplated Ni has been studied. It is established that the ultrasonic agitation at the substratesurface during deposition impacts the intrinsic stresses making it possible to increase deposition rate viacurrent density, with stress-free or low-stress levels in the Ni layers. Reduced variations of the intrinsicstress over the surface with the current density is a further important result. Filling of grooves byelectroplating of Ni using ultrasonic agitation is demonstrated. This is due to increasing mass transport ofspecies into the grooves compared to conventional pumped agitation. The enhanced filling propertiesmakes it possible to electroplate Ni in the bottom of high-aspect-ratio grooves. In order to industriallyimplement new nanocomposite coatings on electronic connectors, studies have been performed regardingthe thermal diffusion barrier properties against Cu for Ti-Si-C and Ti-Si-C-Ag nanocomposites, depositeddirectly onto Cu substrates or with sputtered Ni, Ti or electroplated Ni as an intermediate coating. Theapplication of an electroplated Ni diffusion barrier coating, hinders Cu from reaching the surface of thenanocomposites. Also, Ti-Si-C-Ag nanocomposite deposited on magnetron sputtered Ni or Ti on Cusubstrates hinder Cu from diffusing to the surface after annealing. The contact resistance of Ag-Pdtopcoated Ti-Si-C-Ag-Pd and Ti-Si-C-Ag nanocomposite coatings in contact with hard gold is shown tocompete with hard gold in contact with itself, as electrical contact coatings at contact forces around 5 N.Ag-Pd topcoated Ti-Si-C-Ag-Pd in contact with hard gold is shown to have approximately the same contactresistance as hard gold in contact with hard gold at contact forces around 0.1 N, which here is in the 10 mΩrange, while Ti-Si-C-Ag nanocomposite coatings in contact with hard gold has a contact resistance that isup to 10 times higher. The overall contribution of this thesis can be summarised as a deeper knowledge andunderstanding of techniques and coatings, that help reduce cost and increase reliability of electronics.

This Thesis explores the deposition techniques of magnetron sputtering and high velocity oxy-fuel (HVOF) spraying for Ti2AlC as a promising high-temperature material. Magnetron sputtering aims at producing thin (≤1 μm) Ti2AlC films of high crystal quality for use as a model system in understanding the material’s basic properties. HVOF is a new method for deposition of thick (≥200 μm) coatings by spraying Ti2AlC powder, with the aim of transferring the good bulk properties to coatings. The oxidation behavior of Ti2AlC coatings has been investigated for temperatures up to 1200 °C in air. As-deposited Ti2AlC(0001) thin films decompose into TiC during vacuum annealing at 700 °C by out-diffusion of Al as shown by x-ray diffraction analysis. The release of Al starts already at 500 °C in ambient air as driven by aluminum oxide formation on the film surface where the oxide initially forms clusters as observed by electron microscopy. While sputtering from a Ti2AlC target is simpler than by using different elemental targets, the resulting film composition differs from the target stoichiometry. This is due to differences in energy and angular distribution of the sputtered species and evaporation of Al at substrate temperatures above 700 °C. The composition can be compensated for by adding Ti to bind the Al and obtain phase-pure Ti2AlC coatings. For HVOF, I demonstrate how the total gas flow of a H2/O2 mixture (441-953 liter/min) and the powder grain size (30-56 μm) determine the thickness, density, and microstructure of the coatings. High gas flow and small grain size yield thick coatings of 210 μm with a low porosity of 2-8 % and a tensile stress of ≥80 MPa. A fraction of the Ti2AlC powder decomposes during spraying into TiC, Ti3AlC2, and Ti-Al alloys. The coatings also contain as much as 25 at.% O since the powder partly oxidizes during the spraying process. Increasing the powder size and decreasing the total gas flow yield a higher amount of Ti2AlC, but produces thinner coatings with lower cohesion. Post-annealing of the coatings at 900 °C in vacuum increases the Ti2AlC content due to a reversible phase transformation of the as-sprayed material. The high oxygen content, however, hinders the coating to completely transform into Ti2AlC and deteriorates its oxidation resistance. The work thus offers insights to the key parameters for optimizing Ti2AlC coating processing.

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Hard coatings are often used for protection of tool surfaces due to coating properties like low friction and high wear resistance. Even though many of the hard coatings have been tested for wear, it is important to try new wear test setups to fully understand tribological mechanisms and the potential of hard coatings. Few experiments have been performed with dual-coated systems where the sliding contact surfaces are coated with the same, or different, hard coating. The dual-coated system could be the solution to many new technical devices and perhaps a further improvement of conventional coated systems. In this thesis, the wear tests of dual-coated systems were performed in dry reciprocating sliding mode at room temperature. This, quite off the ordinary, wear test setup was performed to study selected hard coatings and set focus on wear mechanisms in forthcoming future surface coating application areas like MEMS and orthopedic implants. Wear tests of four different PVD hard coatings, CrN, TiAlN, WC/C and diamond-like coating (DLC) were performed in a slider-on-flat-surface (SOFS) tribo-tester with reciprocation sliding mode at room temperature and dry sliding with TiAlN coated counter body. Wear mechanisms and the amount of wear were estimated, by investigation of the wear scars produced in SOFS, by means of scanning electron microscopy (SEM), atomic force microscopy (AFM) and optical profilometer (OP). Typical wear mechanisms found for coated surfaces in reciprocation sliding contact were crack formation, surface flattening for shorter sliding distance, elongation of surface defects, debris and thin film formation. Two types of film formation were found: tribo-oxidation film and formation of a self-lubrication film. The tribo-oxidation was the most evident for CrN and the formation of a self-lubrication film was revealed for DLC, where smearing of asperities were the initiation of the process. The DLC coatings showed lowest friction coefficient and worn volume of all the selected hard coatings. Adhesion measurements were performed for all coatings by AFM. Both the unworn and worn surface of each coating were investigated and two coatings, DLC and TiAlN, showed low adhesion forces, which indicated promising properties for small scale devices like MEMS and NEMS with coated, non-sticking, surfaces. / <p>Grundutbildningsprogram: Civilingenjör Bred Ingång Inriktning: Civilingenjör Maskinteknik och Materialteknik</p>

Background Physical activity has many benefits, including the prevention of multiple different diseases. One way to perform physical activity is through resistance training, where some sort of resistance is used to increase the load on the muscles during contraction. For training the upper-body, the bench press exercise is a good option. However, not everyone has the equipment to perform this exercise. The push-up exercise has a similar movement pattern and uses the same muscles as well as no requirement for equipment. Therefore, it would be interesting to see which exercise activates the pectoralis major and triceps brachii, respectably, more. Aim The aim of this study was to compare the muscle activation of the pectoralis major and triceps brachii during push-up and bench press with push-up replicated resistance through EMG-testing. Method 21 male subjects participated in this study. EMG measurement was used on the pectoralis major and triceps brachii to record muscle activity. Following a MVIC test for both muscles, to get a reference value, five repetitions of the bench press exercise at 64% of the subject’s body weight, at rate of 40 beats per minute. Following a three-minute rest, the subjects performed five repetitions of the push-up exercise at the same rate. Three of the five repetitions were selected for further analysis. All data collected was converted to percent of MVIC (%MVIC) before any analysis. Results The results of this study showed a significantly higher activation of the pectoralis major during the bench press exercise compared to the push-up exercise (p=0.014). The results did not show a significant difference in the activation of the triceps brachii during the two exercises. Conclusion This study shows that for training the pectoralis major, the bench press exercise is preferable to the push-up exercise at the same load. For training the triceps brachii, the bench press and pushup exercises seem interchangeable at the same load.

Bakgrund: Inom golfbranschen finns behovet av att alltid förbättra sitt golfspel då konkurrensen är enormt stor inom världseliten. En viktig faktor inom golfen är golfswingen och ju högre klubbhastigheten i själva golfswingen ju länge blir utslaget så länge precisionen är densamma. Klubbhastighet kan förbättras med ökad styrka, och ett sätt som en styrkeökning kan ske kortvarigt är med hjälp av postaktiveringspotentiering (PAP) och därmed påverka ökning av klubbhastigheten.  Syfte: Studiens syfte var att undersöka om genomförandet av en tyngre rotationsövning direkt följt av en golfswing ger en postaktiveringspotentieringseffekt på klubbhastigheten jämfört med bara vila. Metod: En cross-over studie med 2 protokoll, samt 19 testpersoner som jämförde skillnaden i klubbhastighet mellan protokoll 2; en tyngre pre- övning i form av 5 tunga rotationer i Quantum innan 5 golfswingar och protokoll 1; 5 golfswingar med enbart vila som aktiveringsövning. Resultat: Ingen signifikant skillnad i klubbhastighet fanns varken i protokoll 1 med vila som intervention (p=0,65) eller i och protokoll 2 med PAP som intervention (p=0,94). Slutsats: I avsaknad av tidigare studier samt nuvarande studies negativa resultat är det fortfarande okänt huruvida postaktiveringspotentiering existerar i en golfswing och om det kan påverka klubbhastigheten. / Background: Within the golf industry, there is constantly a need to improve the golf game, as competition is high in the world elite. An important factor in golf is the golf swing, the higher club speed, the longer shot if precision is maintained. The club speed can be improved with increased strength, and one way to increase the strength is by adding post activation potentiation (PAP) and thus affecting the club speed. Purpose: The purpose of the study was to investigate whether the implementation of a heavy rotational exercise directly followed by a golf swing gives a post-activation potentiation effect on club speed compared to just resting. Method: A cross- over study with 2 protocols. 19 participants completed protocol number 2; with the content of a heavier pre- exercise rotation in Quantum, performed 5 times followed by 5 golf swings and also protocol 1, with the content of 5 golf swings with exclusively rest as a pre- activation exercise. Results: No significant difference was found in the club speed between protocol 1 with only rest as the intervention (p=0,65) and protocol 2 with PAP as intervention (p=0,94). Conclusion: In the absence of previous studies and with the negative results in the current study, it is still unknown whether post-activation potentiation exists in a golf swing and if it can affect club speed.

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De senaste decennierna har TIMMS undersökningar visat att svenska elevers resultat försämrats inom de naturvetenskapliga ämnena. Forskningen menar att möjliga faktorer till dessa resultat kan bero på elevernas inställning till ämnet samt hur undervisningen är utformad. Denna studie syftar till att undersöka litteratur kring elevers föreställningar kring naturvetenskapliga begrepp, med fokus på matspjälkning och näringsupptag, samt hur lärare undervisar om mat och hälsa i naturvetenskap. I studien har internationella och nationella litteraturer behandlats, dessutom har valda lärandeteorier analyserats med fokus på konstruktivismen och det sociokulturella perspektivet. I Studien har vi även behandlat olika undervisningsmetoder verksamma lärare använder sig av för att främja elevernas kunskapsinhämtning. Då studiens metod är en litteraturstudie har vetenskapliga artiklar från olika databaser analyserats och valts ut efter studiens valda syfte. Resultatet av vår litteraturstudie visar på att elever har svårigheter att förstå och förklara naturvetenskapliga begrepp. Elever använder sig av vardagsbegrepp när de ska förklara vad som sker i magsäck och tarm. Resultatet visar att elever tillämpar sina tidigare erfarenheter för att förklara matspjälkning och näringsupptag. Resultatet innefattar också två lärandeteorier som presenterar deras synsätt och förhållningssätt i de naturvetenskapliga ämnena. Resultatet visar även att lärarens kvalité på undervisningen har en stor betydelse för elevernas kunskapsinhämtning. Enligt forskningen är det lärarens egna attityder och kunskaper till ämnet som speglar undervisningen, där det är viktigt att lärare har en korrekt förståelse för det aktuella begreppet. Detta betyder att lärare med hög ämneskunskap och god pedagogisk skicklighet gynnar elevers begreppsförändring.