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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
71

Nanotechnology Start-ups - Intellectual Property for Generating Value

Hellström, Amanda, Nilsson, Sara January 2018 (has links)
Purpose – The purpose of this thesis was to increase the understanding of how formal and informal intellectual property may affect value generation of strategic and financial values within the nanotechnology start-up sector. Method – This study had an inductive approach through a qualitative multi-case study. The data collection was carried out through 23 interviews, including four exploratory interviews and 19 semi-structured interviews. The collected data was continuously analyzed in order to identify concepts, themes and aggregated dimensions. The collected data was analyzed through two categories, namely type of intellectual property and prioritized type of value desired. Findings – Through protecting innovations nanotechnology start-ups seek both strategic and financial values. The findings show nanotechnology start-ups seek strategic values in the form of trustworthiness through qualified recognition, ability to increase in market share, and having a competitive presence on the market. The findings further show nanotechnology start-ups seek financial values in the form of effective resource allocation, direct income from market transactions, and ability to attain investors. Furthermore, the findings suggest that for nanotechnology start-ups to effectively generate strategic and financial values it can be beneficial to combine formal and informal IP where a combination of trade secrets and patents can be valuable. Theoretical contributions – The analysis resulted in a grounded theory articulation in the form of a conceptual framework describing the relationships between the type of IP and how it may affect value generation for nanotechnology start-ups. This study adds to previous research that aspects fulfilling market demands can be effectively protected by patents, and aspects difficult to reverse engineer can be effectively protected by trade secrets in order to generate strategic and financial value. This study also adds to theory by identifying enablers describing how nanotechnology start-ups can generate strategic and financial values, and which type of IP is associated with each enabler. Practical implications – This study provide managers within the nanotechnology start-up sector with a framework suggesting how to generate different values from protecting innovations. The study further concludes that there are six important aspects to consider in creating effective IP strategies within the nanotechnology start-up sector. These aspects include; mapping the technological environment and the commercial market, determining which actual strategic and financial values are important for the start-up, protecting different aspects of an innovation with different types of IP, having trade secrets on aspects of an innovation that are hard to reverse engineer, to formally protect aspects of an innovation that fulfills market demand, and making a plan for how the rights attained can generate value.
72

Magnetic fluids under applied field studied by light scattering and microscopy

Braesch-Andersen, Anna January 2017 (has links)
The optical response of several magnetic nanoparticle dispersions is studied by angle resolved transmittance at wavelength of 600 nm in zero-field and under an applied magnetic field of 0.1 T, with the purpose of exploring to what extent this could be used as a method of monitoring the colloidal dispersions. In an external magnetic field, magnetic particles will start to order into needle-like structures aligned with the field, which was observed by microscopy. This will change the light scattering caused by the particles. Results showed a clear effect from applying the magnetic field by a dip in the transmitted intensity at angles around 3-5 degrees. The scattering is compared to that of a homogeneous infinite cylinder and theoretical explanations to the effect are discussed. Spectrophotometry at wavelengths between 300-1100 nm is performed and compared with calculations from Kubelka-Munk approximation to give a first characterization of the particle dispersions. Particles used in this project are magnetite, Fe3O4, and maghemite, gamma-Fe2O3, nanoparticles with sizes ranging from 5-250 nm.
73

Modélisation et caractérisation des matériaux nanocomposites par des méthodes diélectriques / Characterization and modeling of nanocomposite insulating materials by dielectric methods

Preda, Ioana 27 June 2013 (has links)
"Il ya beaucoup de place vers le bas!", ait déclaré Richard Feynman dans son discours sur les nanotechnologies en 1959, ouvrant un nouveau monde de la science et de la technologie! L'idée d'utiliser des nanoparticules afin d'améliorer les propriétés diélectriques des polymères qui étaient déjà en cours d'utilisation a suscité l'intérêt des chercheurs dans les deux dernières décennies. Nanocharges tels que la silice, l'alumine, l dioxyde de titan, etc, mais aussi des particules plus grosses comme les argiles ou les nanotubes de carbone ont été mélangés avec les polymères «classiques» afin d'améliorer les propriétés du polyéthylène, des résines époxy, de polypropylène, etc.De nos jours, le rendement de conversion d'énergie de générateurs électriques est limitée par des problèmes thermiques et électriques, limitations étant surtout liées à la qualité des rubans isolants appliqués sur les barres en cuivre. En conséquence, des rubans isolants innovants basés sur des de matériaux nanostructurés ont été envisagés pour augmenter le rendement énergétique des alternateurs et le but de ce travail est d'étudier ces matériaux innovants et de comparer leurs propriétés avec celles des matériaux déjà utilisés, afin d'aider à choisir le meilleur matériau composite pour les futurs rubans. Après une brève introduction sur le contexte de ce travail, on a présenté bref état de l'art les propriétés des polymères époxy, avec un débat sur les propriétés électriques de la matrice polymère choisie (résine époxyde), ses propriétés chimiques et thermiques. Ensuite, les nanocharges choisies et leurs propriétés spécifiques sont présentés, en discutant les différentes étapes du procédé de fabrication, aussi qu'un débat sur les phénomènes qui apparaissent à l'échelle nanométrique et leur éventuelle influence sur les propriétés du matériau composite fini.Différents groupes de matériaux composites à base d'époxy remplis de silice nanométrique, argile organique ou de nitrure de bore sont analysés dans ce travail. Afin de caractériser et interpréter leurs propriétés, plusieurs outils ont été utilisés: la microscopie imagerie, la caractérisation thermique ainsi que les méthodes d'investigation à fort ou faible champ électrique. Leur caractéristiques sont ressemblés et différents observations sur des propriétés «générales» ou «spécifiques» des matériaux composites ont été observés et discutés par rapport à l'influence du type de charge utilisée, de son traitement ou de son poids total sont débattues.Enfin, un modèle numérique basé sure une généralisation de la loi des mélanges sera utilisée afin de prédire la réponse diélectrique des matériaux composites ainsi que les paramètres (taille, permittivité) de l'interphase, «l'ingrédient« magique du mélange matrice de remplissage. Le modèle présenté nous a permis de donner un lien entre les différents matériaux et de valider les résultats obtenus expérimentalement. Une approche par éléments finis est utilisée.Ce manuscrit s'achève par des conclusions sur le travail présenté et il laisse entrevoir les perspectives dans l'analyse complexe des polymères nanocomposites . / “There's plenty of room of the bottom!” said Richard Feynman in his talk on top-down nanotechnology in 1959, bringing into the spot light a new world of science and technology ! The idea of using nanoparticles in order to improve the dielectric properties of the polymers that were already in use attracted the interest of researchers for the last two decades. Nanofillers such as silica, alumina, titania etc, but also larger particles such as clays or carbon nanotubes were mixed with the “classic” polymers in order to improve the properties of polyethylene, epoxy resins, polypropylene etc. Since nowadays the energy conversion efficiency of electrical generators is restricted by thermal and electrical issues, these limitations can be related to the electrical insulator tapes themselves. Thus, innovative insulating tapes based on nanostructured material scenarios to address the energy saving concern are intended and the purpose of this work is to investigate these innovative materials and to compare their properties with those of the materials already in use, in order to help choosing the best composite material for the future tapes.This works begins with a state of the art regarding the properties of epoxy polymers. Their chemical, thermal and dielectric properties are presented. Afterwards, the chosen fillers and their specific properties are presented. The influence of the chosen fillers as well as different steps of the nanocomposite materials manufacturing process are presented and the discussion ends with a debate on the phenomena appearing at the nanometric scale and their possible influence on the properties of the finite composite material .Different materials groups of epoxy based composites filled with nanometric silica, organoclay or boron nitride are analyzed afterwards. In order to characterize and interpret their properties, several tools were used: imaging microscopy, thermal characterization as well as high and low electric field investigation methods. A debate trying to distinguish between so called “general” or “specific” behavior of the composite materials with respect to the normal, unfilled polymer is also presented. The influence of the type of filler, its treatment or its weight total percentage will be are chosen as comparison criteria. Finally, a numerical model based on Finite Element Method approximation was used in order to predict the dielectric response of the composite materials as well as the specific parameters (size, permittivity) of the interphase, the magic “ingredient” of the matrix-filler mix. The presented model allowed us to give a connection between the different materials and validate the experimentally obtained results. This manuscript ends with conclusions on the presented work and suggests possible future works in the complex analysis of polymer nanocomposites.
74

InP/Si Template for Photonic Application

Larsson, Niklas January 2015 (has links)
In this work an epitaxial layer of Indium Phosphide (InP) has been grown on top of a silicon substrate using the Corrugated Epitaxial Lateral Overgrowth (CELOG) technique. The grown InP CELOG top layer typically has a poor surface roughness and planarity. Before this surface can be used for any processing it has to be smooth and planarized. For this purpose a two-step Chemical Mechanical Polishing (CMP) technique has been investigated and developed. In the first step commercially available Chemlox has been used to planarize the sample. In the second step Citric Acid (CA) and sodium hypochlorite (NaClO) has been mixed together to form abrasive-free polishing slurry. The second step has been developed to remove defects introduced by the first step. This surface is prepared to demonstrate that a photonic device such as a quantum well can be realized in a Photonic Integrated Circuit (PIC). A quantum well was grown on the polished CELOG InP/Si sample and measured with Atomic Force Microscopy (AFM), Scanning Electron Microscopy (SEM), X-ray Diffraction (XRD) and Photoluminescence (PL). The roughness was improved with CMP from 33.2 nm to 12.4 nm. However the quantum well did not give any response in the PL measurements. / I detta arbete har ett epitaxiellt lager indiumfosfid (InP) blivit växt på ett kiselsubstrat med hjälp av en korrugerad epitaxial lateral överväxt (CELOG) teknik. Det översta lagret av den CELOG växta ytan har ofta en väldigt ojämn yta. Innan denna yta kan användas till någon fortsatt utveckling måste den vara slät och plan. Det översta lagret har polerats med hjälp av en två-stegs kemisk mekanisk polerings (CMP) teknik. I det första steget har komersiellt tillgänglig Chemlox använts för att planarisera ytan. I det andra steget har citronsyra (CA) och natrium hypoklorit (NaClO) blandats samman för att bilda ett partikelfritt polermedel. Det andra steget har tagits fram för att ta bort defekter introducerade I det första steget. Ytan är preparerad för att demonstrera att en fotonisk enhet, t.ex. en kvantbrunn kan realiseras I en fotonisk integrerad krets (PIC). En kvantbrunn växtes fram på det polerade CELOG InP/Si provet och mattes med hjälp av atomkraftsmikroskop (AFM), scanning electron mikroskopi (SEM), röntgendiffraktion (XRD) och fotoluminisens (PL). Ytojämnheten förbättrades med hjälp av CMP från 33.2 nm till 12.4 nm. Dock så gav ej kvantbrunnen någon respons I PL-mätningarna.
75

Design of Multi-function Polymeric Nanoparticles for Theranostic Application / Design av multifunktionella polymera nanopartiklar för teranostisk tillämpning

Yamani, Zuhoor January 2019 (has links)
Block copolymer nanoparticles (NPs) have gained great attention among researcher for various medical application mainly due to their extraordinary optical, chemical, and biological properties. The current thesis presents design of multifunctional polymeric NPs for imaging and drug delivery system (DDS) with an in-vitro study of their participation in drug release and cell viability. The NPs were synthesized using reversible addition chain fragmentation transfer (RAFT)-mediated emulsion polymerization via polymerization induce self-assembly (PISA) approach. The environment-friendly emulsion polymerization process of n-buytl acrylate (n-BA) in water is highly efficient. The process produced uniform NPs which would have control over the particle size and molecular weight of the compound. Herein we report a novel simultaneous encapsulation of camptothecin (CPT) and Nile red (NR) into poly(ethylene glycol) methyl ether methacrylate-co-N-hydroxyethyl acrylamide-b-poly n-buytlacrylate (PEGA-co-HEAA)-b-P(n-BA) during the particles formation with a small particle size of 66 nm, high conversion ~80% and encapsulation efficiency of ~50%. The In vitro drug release of the CPT from the NPs exhibited an initial burst (70-80%) within 6h. cell viability was evaluated for the NPs against RAW 264.7 cell line, which indicated the designed NPs are biocompatible and not toxic.
76

Characterization of graphene-based sensors for forensic applications : Evaluating suitability of CVD graphene-based resistive sensor for detection of amphetamine

Talts, Ülle-Linda January 2019 (has links)
Recent improvements in sensor technology and applications can be partly attributed to the advancements in microand nanoscale fabrication processes and discovery of novel materials. The emergence of reliable and inexpensive methods of production of monolayer materials, such as graphene, has revealed the advantageous electronic properties which when utilized in sensory elements can significantly enhance response to the input signal. Hence, graphene-based sensory devices have been widely investigated as the exotic properties of the carbon nanomaterial allow for cost-efficient scalable production of highly sensitive transduction elements. Previous studies have shown successful detection of n-type dopants such as ammonia and low pH solution. As the amine group in amphetamine molecules is known to behave as an electron donor, in this study, graphene conductivity changes in response to exposure to amphetamine salt solutions were investigated.Graphene formed by chemical vapour deposition (CVD) was transferred onto SiO2 substrate with gold electrodes to form a resistive transducer. Observation of large intensity ratio of graphene characteristic 2D and G peaks as well as minimal defect peaks from Raman spectroscopy analysis proved the integrity of the carbon monolayer was maintained. The atomic force microscopy and resistance measurements results showed the storage of these sensory elements in ambient conditions results in adsorption of impurities which considerably influence the electronic properties of graphene. Upon exposure to amphetamine sulfate and amphetamine hydrochloride, conductivity decrease was detected as expected. Signal enhancement by excitation of 470nm light did not show a significant increase in response magnitude. However, the low reliability of sensor response limited further analysis of the chemical sensor signal. Non-selective sensor response to amphetamine can be detected, but improvements in device design are needed to minimize contamination of the graphene surface by ambient impurities and variations in the sensor system. / De senaste förbättringarna i sensorteknik och applikationer kan kopplas till framsteg inom framställningsprocesser berörande mikrooch nanoskala samt upptäckt av nya material. Framväxten av tillförlitliga och billiga produktionsmetoder av monoskiktmaterial, såsom grafen, har avslöjat de fördelaktiga elektroniska egenskaperna som när de används i sensoriska element och förbättrar signalresponsen till inputsignalen. Grafenbaserade sensoriska applicationer har undersökts allteftersom de exotiska egenskaperna hos kolbaserade nanomaterial möjliggör en kostnadseffektiv skalbara produktion av högkänsliga transduktionselement. Tidigare studier har framgångsrikt visat detektion av n-typ substanser såsom ammoniak och låg pH-lösning. Eftersom amingruppen i amfetaminmolekyler är känd för att verka som en elektrondonator, undersöktes i denna studie konduktivitetsändringar i grafen under exponering för amfetaminsaltlösningar.Grafen bildad genom kemisk ångavsättning (CVD) överfördes på Si02-substrat med guldelektroder för att bilda en resistiv omvandlare. Observation av intensitetförhållandet mellan de grafenkarakteristiska 2Doch G-topparna samt minimala defekttoppar från Ramanspektroskopianalysen visade att kolmonolagrets struktur upprätthölls. Resultaten av atomkraftmikroskopi och resistansmätningar visade att lagringen av de sensoriska element i normala omgivningsförhållanden resulterar i adsorption av föroreningar som avsevärt påverkar grafens elektroniska egenskaper. Vid exponering för amfetaminsulfat och amfetaminhydroklorid upptäcktes en förväntad konduktivitetsminskning. Signalförbättring genom excitation av 470nm-ljus visade inte en signifikant ökning av svarstyrkan. Den låga tillförlitligheten hos sensorn begränsade emellertid ytterligare analys av den kemiska sensorsignalen. Sensorns icke-selektiva svar på amfetamin kan detekteras, men förbättringar i enhetens konstruktion behövs för att minimera kontaminering av omgivande föroreningar på grafenytan och variationer i sensorsystemet.
77

Functionalization and Evaluation of Nanoparticle Probes for the Development of a 14-Plex Diagnostic assay / Funktionalisering och Utvärdering av Nanopartikel Sonder för Utveckling av 14-Multiplexerad Diagnostisk panel

Narmack, Samuel January 2021 (has links)
Detta projekt var ett samarbete mellan Aplex Bio AB och Scilifelab. Projektets mål var att utveckla en molekylär diagnostisk panel med förmågan att detektera och diskriminera mellan 14 olika typer av patogener. Projektet innehåller 4 kapitel med fokus på olika mål. I första kapitlet utvecklades en metod för att karakterisera emissioner av fluorescerande nanopartikel kluster. Den första utvärderade metoden utnyttjade klick-kemi för att binda nanopartiklarna till makrostrukturer uppbyggda av amplifierat DNA. Den andra utvärderade metoden skapade aggregerade komplex av nanopartiklar med amplifierat DNA för att utvärdera partiklarnas emissioner. I kapitel 2 av projektet användes azid-funktionaliserade nanopartiklar levererade av Aplex Bio AB för att tvärbinda DBCO modifierade oligonukleotider. Sedan utvecklades en hybridiserings baserad metod för att kvantifiera relativa mängden oligonukleotider på partiklarna. Denna metod användes för att reproducerbart funktionalisera partiklar och utveckla nanopartikel-sonder som kan binda till DNA genom hybridisering. I kapitel 2 utvärderades även hur effektivt och specifikt de utvecklade nanopartikel-sonderna hybridiserar till DNA. I kapitel 3 utvärderades amplifiering av syntetiska ssDNA sekvenser valda från genetiska markörer av 14 patogener, DNA amplifierades med metoden RCA. Målet var att utvärdera specificiteten av amplifieringen. Specifik amplifiering av varje DNA sekvens i panelen var en förutsättning för att möjliggöra detektion och diskriminering av alla patogener i panelen. I kapitel 4 var målet att utveckla en kostnadseffektiv metod för att funktionalisera nanopartiklar med oligonukleotid sekvenser. För att göra detta användes DBCO-NHS-ester reagens och amin-modifierade oligonukleotider. Förverkligande av detta projekt skulle skapa en diagnostisk panel med potentialen att påverka det diagnostiska fältet på en global skala. När detta projekt är fullt utvecklat kan panelen modifieras för detektion av önskade DNA/RNA sekvenser vilket möjliggör ett mångfalt av applikationer, detta skulle göra panelen konkurrerande med dagens diagnostiska metoder då den kan användas i existerande mikroskopiuppsättningar. / This work was a collaboration between Aplex Bio AB and Scilifelab with the aim of developing a molecular assay capable of detecting and discriminating between 14 different pathogenic targets. There are 4 chapters with focus on different goals. In chapter one a method of evaluating emissions of fluorescent nanoparticle clusters was developed. The first approach of evaluating nanoparticle emissions was to utilize click chemistry to bind nanoparticles to macroscale structures of amplified DNA targets. The second evaluated approach was the formation of aggregated complexes of nanoparticles and amplified DNA targets. The second chapter of the thesis used azide functionalized nanoparticles supplied by Aplex Bio AB to utilize azide groups as crosslinkers and use them to functionalize the nanoparticles with DBCO oligos. A hybridization-based method was then developed to quantify relative oligo densities on the nanoparticles, enabling reproducible oligo functionalization of nanoparticles, producing nanoparticle probes that can bind to DNA. The final task of chapter 2 was evaluating the binding efficiency and specificity of the developed nanoparticle probes. The third chapter of the thesis evaluated amplification of synthetic ssDNA sequences corresponding to genetic markers of 14 pathogenic targets using RCA. The goal was to confirm specificity of chosen padlock probes and corresponding synthetic targets for each pathogen. Specific amplification of each target was a prerequisite to enable detecting and discriminating between the 14 pathogenic targets. In chapter 4 the goal was to develop a cost-effective method of oligo functionalization for nanoparticles. This chapter evaluated two main approaches of using DBCO-NHS-ester reagents to perform DBCO modification of amine-oligos. The realization of this work would develop an assay that has the potential to impact the field of diagnostics on a global scale. When fully developed, the molecular assay can be modified to detect any RNA/DNA targets which enables numerous applications, making the assay a competitive diagnostic tool which can be implemented in existing microscopy systems.
78

Vertical charge transport in conjugated polymers

Skrypnychuk, Vasyl January 2017 (has links)
Conjugated polymers are novel organic electronic materials highly important for organic photovoltaic applications. Charge transport is one of the key properties which defines the performance of conjugated polymers in electronic devices. This work aims to explore the charge transport anisotropy in thin films of P3HT, one of the most common conjugated polymers. Using X-ray diffraction techniques and charge transport measurements, the relation between vertical charge transport through thin P3HT films and structure of the films was established. It was shown that particular orientations of crystalline domains of P3HT, namely face-on and chain-on, are beneficial for vertical charge transport. These orientations provide the efficient pathways for the charges to be transported vertically, either via π-π stacking interaction between the adjacent conjugated chains, or via the conjugated chain backbones. It was also demonstrated that particular orientations of crystallites are favourable for the formation of interconnected percolated pathways providing enhanced vertical charge transport across the film. Deposition of P3HT on most commonly used silicon substrates typically results in the formation of mostly edge-on orientation of crystallites which is unfavourable for vertical charge transport. Nanoimprint lithography was demonstrated as a powerful processing method for reorienting the edge-on crystalline domains of P3HT into chain-on (vertical) orientation. It is also shown that thin P3HT films with preferentially face-on orientations of crystallites can be deposited on graphene surface by spin coating. Using patterning of thin P3HT films by nanoimprint lithography, unprecedentedly high average vertical mobilities in the range of 3.1-10.6 cm2 V-1 s-1 were achieved in undoped P3HT. These results demonstrate that charge transport in thin films of a relatively simple and well-known conjugated polymer P3HT can be significantly improved using optimization of crystallinity,orientation of crystallites, polymer chain orientation and alignment in the films.
79

Processing of Sub-micrometer Features for Rear Contact Passivation Layer of Ultrathin Film Solar Cells Using Optical Lithography

Roxner, Evelina, Olsmats Baumeister, Ronja January 2019 (has links)
Thin film copper, indium, gallium, selenide (CIGS) solar cells are promising in the field of photovoltaic technology. To reduce material and fabrication cost, as well as increasing electrical properties of the cell, research is ongoing towards ultra-thin film solar cells (absorption layer thickness less than 500 nm). Ultra-thin CIGS solar cells has shown a decrease in interface recombination and improved optical properties when adding a rear contact passivation layer of aluminium oxide. In this work, the process of creating sub-micrometer features of a passivation layer using conventional optical lithography is investigated. To specify, the objective was to optimize the development conditions in the optical lithography process when fabricating equidistant line contacts in aluminium oxide with 800 nm feature size. It was found that line contacts with smaller feature sizes require longer development time, than line contacts with larger feature sizes. The experiments conducted showed that the pre-set development and exposure conditions used by the NOA group are not optimized for 800 nm or smaller line contacts. Further, for the optical lithography process, silicon substrates are not comparable with substrates of soda lime glass coated with molybdenum. Slight underdevelopment of a sample, showed line contacts smaller than the resolution of the laser used in the exposure – suggesting an alternative method of processing small line contacts with optical lithography.
80

Importance of atomic force microscopy settings for measuring the diameter of carbon nanotubes / Betydelsen av atomkraftmikroskåpets inställningar för mätningar av diametern hos kolnanorör

Almén, Anton January 2019 (has links)
Carbon nanotubes (CNTs) have gathered a lot of interest because of their extraordinary mechanical, electrical and thermal properties and have potential applications in a wide variety of areas such as material-reinforcement and nano-electronics. The properties of nanotubes are dependent on their diameter and methods for determining this using atomic force microscopy (AFM) in tapping mode assume that the measured height of the tubes represent the real diameter. Based on early, faulty calculations, the forces in tapping mode were assumed to be much lower than in contact mode, however it was later shown that forces in tapping mode can at point of impact rival the forces present in contact mode. This means that there is a potential risk of tube deformation during tapping mode measurements, resulting in incorrectly determined diameters. This work studies CNTs deposited on a silicon-substrate to analyze the effect of three common AFM settings (tapping frequency, free oscillation amplitude and setpoint) to determine their effect on measured CNT diameters and recommendations for choosing settings are given. / Kolnanorör har skapat mycket intresse på grund av sina extraordinära mekaniska, elektriska och termiska egenskaper och har lovande tillämpningar inom en mängd olika områden så som materialförstärkning och nanoelektronik. Kolnanorörens egenskaper påverkas kraftigt av deras diameter och de metoder som använder sig av atomkraftsmikroskopi(AFM) för att mäta diametern hos rören antar att den höjd-data man får fram är ett bra mått på den verkliga diametern hos rören. Baserat på tidiga, felaktiga beräkningar, antog man att kraften i ’tapping mode’ skulle vara mycket lägre än i ’contact mode’ vilket skulle leda till att man inte deformerar ytan man undersöker. Senare forskning visade att kraften mellan spets och prov kan vara lika stor eller rentutav större i tapping mode än i contact mode under det ögonblick då spetsen slår ner i provytan. Det medför att det finns en potentiell risk för att man deformerar kolnanorören när man mäter på dom vilket skulle resultera i att man får felaktiga värden på deras diametrar. Under det här projektet har kolnanorör som placerats på ett kisel-substrat undersökts för att analysera hur tre vanliga inställningar hos AFMet påverkar de erhållna värdena för diametern hos kolnanorören. De tre inställningarna som testats är svängnings-frekvensen, svängnings-amplituden i luft och börvärdet hos svängnings-amplituden.

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