In this paper, a nanometer-sized gold electrode with an effective radius around several tens of nanometers has been modified with a monolayer of alkanethiols. There are pinholes in the monolayer, and the pinholes can be used as very small electrode. Our evaluation shows that it is possible to have only one pinhole on the monolayer covered electrode. The single pinhole electrode has been used to study the electrochemical behaviors of fast and slow electrochemical reactions. Our results show that the electrochemical response of a slow electrochemical reaction is not a Butler-Volmer response if the electrode is small enough.

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Il existe une très forte demande en biocapteurs pour la détection d’agents pathogènes dans le domaine environnemental et médical. Dans ce contexte, le contrôle de l’état de surface des biocapteurs joue un rôle crucial. Les monocouches auto-assemblées (Self-Assembled Monolayers, SAMs) permettent de fonctionnaliser de manière homogène et reproductible ces surfaces. Ces SAMs sont généralement obtenues à partir d’agents de couplage siliciés à longue chaîne alkyle. Mais, ces composés sont souvent difficiles à synthétiser et à purifier en raison de leurs faibles solubilités dans les solvants organiques. C’est pour cela que nous avons proposé d’introduire une fonction polaire (amide ou urée) au sein de ces films. Ces fonctions permettent également un auto-assemblage des molécules sur le substrat au moyen de liaisons hydrogène entre les molécules. Les nouvelles monocouches fonctionnelles ont été caractérisées entre autres par spectroscopie infrarouge de réflexion-absorption par modulation de polarisation (PM-IRRAS) ce qui a permis d’identifier les différents groupes moléculaires. Ces monocouches ont aussi montré leurs capacités à immobiliser une molécule biologique (Protéine A). / There is an increasing demand for biosensors to detect pathogens in environmental and medical fields. In this context, the control of the surface properties plays an important role. Self-Assembled Monolayers (SAMs) allow to functionalize these surfaces homogeneously and reproducible. SAMs on silicon based surfaces are usually obtained from silylated coupling agents with long alkyl chain. However, these compounds are often difficult to purify owing to their low solubility in organic solvents. That’s why we proposed to introduce a polar function (amide or urea) in the molecular structure. These precursors were also capable of association by H-bonds and offer possibilities to control the organic assembly on the surfaces. The new functional monolayers were characterized by Polarization Modulation Infrared Reflection Adsorption Spectroscopy (PM-IRRAS) and others techniques such as XPS and contact angle in order to identify the different molecular groups on the surface. These functionalized monolayers have also shown their ability to immobilize biomolecules (Protein A).

Eleverna inom Statens institutionsstyrelse (SiS) befinner sig i en speciell skolkontext. Det vanligast förekommande är att elever placeras på SiS utifrån lagen om vård av unga (LVU) och placeringen sker genom tvång (Karlsson & Linde, 2021). Individens hela liv ska rymmas inom institutionen: fritid, behandling och skola (Enell et al., 2018). Inom verksamheten finns särskilda befogenheter där personalen har lagligt stöd att utföra åtgärder som innebär kontroll, disciplinering och uppfostran (Andersson Vogel, 2020). Skolinspektionen (2021) påtalar att flickor inom SiS har högre frånvaro och mår sämre än pojkar inom verksamheten. Granskningen som Skolinspektionen genomfört synliggör behovet av att möta flickornas behov och där tar vår studie avstamp. Studien utgick från en kvalitativ ansats och syftade till att få syn på flickors delaktighet inom SiS skolverksamheter. Studien utfördes genom kvalitativa intervjuer med lärare för att undersöka hur de arbetar för att främja flickors delaktighet.   Framgångsfaktorer som identifierades kunde handla om gruppstorlek där elevantalet är begränsat vilket påverkar undervisningen såtillvida att lärare ges möjlighet att skapa en tillgänglig lärmiljö anpassad efter varje elev. Samarbete med behandlingsavdelningarna framgick som viktigt för att eleverna skulle uppleva trygghet, främja skolnärvaro och möjliggöra kontinuitet. Lärarnas förhållningssätt och bemötande framhölls som central för att eleverna skulle kunna utveckla en bättre skolidentitet.   Studiens resultat visar att vistelsetiden påverkar lärarnas möjligheter till att skapa förändring för elevens skolidentitet. Om vistelsetiden är kort blir förutsättningar att göra förändringar begränsade. Lärarna på SiS vittnar om vissa svårigheter med att erhålla adekvat dokumentation om eleven haft långvariga skolavbrott och senaste huvudman är svår att återfinna. Gemensamt för elevgruppen är en bakgrund i skolmisslyckanden, och dokumentation som återfinns är ofta kring olika åtgärder. Samverkan mellan SiS skolverksamhet, socialtjänsten och elevernas hemskola sker i olika stor omfattning och ser olika ut. Fungerande samverkan verkar gynnande för eleverna inom SiS skolverksamhet.    Några av slutsatserna som studien pekar på är att lärarna arbetar för att främja flickors delaktighet men att förutsättningarna ser olika ut. Det vi kunnat utläsa är att SiS skolverksamhet har genomfört och genomgår förändringsarbete med utgångspunkt i resultat av granskningar som Skolinspektionen, Statens institutionsstyrelse, Statskontoret och Inspektionen för vård och omsorg har genomfört. Utöver detta förekommer även projekt och utvecklingsarbete som görs inom SiS skolverksamheter. När vi ser till omfånget av forskningslitteraturen har SiS skolverksamhet en undanskymd roll jämfört med forskning som berör den vårdande delen av verksamheten. Vi kan dock se tendenser till att SiS som skolverksamhet tar allt större plats och framhålls mer inom litteratur, media, rapporter och inom den egna verksamheten. / The students at The National Board of Institutional Care, “Statens Institutionsstyrelse” (SiS) in Swedish, are in a peculiar school context. Students are most commonly placed at SiS based on compulsory care of children in accordance with Swedish act LVU (Karlsson & Linde, 2021). The individual's entire life must be accommodated within the institution: free time, care and treatment and schooling (Enell et al., 2018). Within the special residential homes there are treatment facilities where the staff has legal support to carry out actions that involve control, discipline, and upbringing (Andersson Vogel, 2020). Girls at SiS have higher absence and greater discomfort than boys in the institution. The Swedish School Inspectorate's (2021) review highlights the demands to meet the girls' needs, which is where our study takes place. The study was based on a qualitative approach and aimed to gain insight into girls' participation at SiS school. The study was carried out through qualitative interviews with teachers to investigate how they work to promote girls' participation.   Group size, where there was a limited number of students, was a success factor that was identified, which affects teaching to the extent that teachers are given the opportunity to create one available learning environment adapted to each student. Another success factor was the cooperation with the care and treatment departments, as this would facilitate the students' feeling of security, promote school attendance, and enable continuity. Lastly, the teachers' approach and treatment were highlighted as central to students being able to develop a better school identity.   The results of the study show that the length of stay for the student affects the teachers' opportunities to create change for the student's school identity. If the length of stay is short, the opportunities to make changes become limited. The teachers at SiS testify to certain difficulties in obtaining adequate documentation about the student if she had long-term school breaks and the last school where they were placed is difficult to find. Common to the student group is a background in school failures, documentation which is found often relates to various action programmes. Collaboration between SiS school, social services and the student’s regular school takes place on a different scale and looks different. Working cooperatively in between these authorities seems beneficial to the students within SiS school.   Some of the conclusions from the study indicators are that the teachers work to promote girls' participation, but the conditions look different between the institutions. What we were able to conclude is that SiS schools involve development work based on the results of reviews that Health and Social Care Inspectorate, SiS, The School Inspectorate and The Swedish Agency for Public Management. In addition to this, there are also projects and development work within SiS school. For the range of the research literature, SiS school has been investigated less frequently compared to research that concerns the treatment part of the institution. However, we can see tendencies towards SiS as a school being mentioned more often and is emphasised more in literature, media, reports and within SiS own work.

Dans le but de développer des matériaux et des dispositifs avec de nouvelles propriétés, l’élaboration de monocouches auto-assemblées (SAM) est un sujet d'intérêt croissant dans le domaine des nanosciences. Les SAM sont des agrégats bidimensionnels formés par des molécules régulièrement espacées sur une surface et liées entre elles par des forces non covalentes. Le domaine des biocapteurs électrochimiques pour la reconnaissance des brins d'ADN est parmi les applications les plus récentes des SAM. Dans ce cadre, nous avons mené une étude théorique des mécanismes fondamentaux engagés lors de l’adsorption de la molécule quinone Jug-C4-thiol sur la surface Au (111). Les résultats ont été confrontés aux mesures expérimentales accessibles réalisées par l’équipe « nano 2D » au laboratoire ITODYS (Université Paris7). Tout d’abord, la théorie de la fonctionnelle de la densité PBE et PBE-D2 a été utilisée pour étudier les mécanismes mis en jeu (physisorption ou chimisorption) lors de l’adsorption de la molécule isolée à la surface de Au (111) et déterminer le site le plus favorable pour chaque mécanisme. La nature de la liaison entre la molécule et la surface de a été finement analysée à l’aide de calculs de densité d’états (DOS) et de différences de densités de charge. Ensuite, l'assemblage de la molécule quinone Jug-C4-thiol sur la surface Au (111) a été étudié. Cet assemblage des molécules a été initié par la formation de configurations de dimère à travers la formation de liaisons intermoléculaires (liaison hydrogène et π-stacking, …). Les spectres infrarouges des configurations les plus stables ont été simulés et confrontés à l’expérience. Et enfin, le mécanisme d’échange entre des molécules « hôtes » (alcanethiols C12H25SH préalablement assemblés sur la surface) et « invitées » (Jug-C4-thiols) a été exploré avec les outils théoriques. L’analyse des résultats a mis en évidence des informations structurales et énergétiques importantes sur la formation de la monocouche moléculaire mixte. / In order to develop materials and devices with new properties, the development of self- In order to develop materials and devices with new properties, the development of self-assembled monolayers (SAM) is a topic of growing interest in the field of nanoscience. SAM are two-dimensional aggregates formed by molecules regularly spaced on a surface and bonded together by non-covalent forces. The field of electrochemical biosensors for DNA strand recognition is among the most recent applications of SAM. In this context, we conducted a theoretical study of the fundamental mechanisms involved in the adsorption of the quinone Jug-C4-thiol molecule on the Au (111) surface. The results were compared to the accessible experimental measurements from the "nano 2D" team at the ITODYS laboratory (Paris 7 University). First, the density functional theory at PBE and PBE-D2 levels was used to study the mechanisms involved (physisorption or chemisorption) during the adsorption of the isolated molecule on the surface of Au (111) and access to the most favorable site for each mechanism. The nature of the binding between the molecule and the surface was finely analyzed using density of states (DOS) calculations and differences in charge densities.Then, the assembly of the quinone Jug-C4-thiol molecule on the Au (111) surface was studied. This assembly of molecules was initiated by the formation of dimer configurations through the formation of intermolecular bonds (hydrogen bonding and π-stacking, etc.). The infrared spectra of the most stable configurations were simulated and compared with the experiment. And finally, the mechanism of exchange between "host" molecules (C12H25SH alkanethiols previously assembled on the surface) and "invited" molecules (Jug-C4-thiols) was explored with the theoretical tools. The analysis of the results revealed important structural and energetic informations on the formation of the mixed molecular monolayer.

The diploma thesis deals with examinations of forces which are acting from road surface on tyres. The aim is to design and build measuring circuit which measure forces in front suspension. The thesis deals with designing of mathematical model in addition describes problematic of strain gauge sensors, their calibration and verification measure in details. The results are data obtained from static and dynamic measurement and outputs from multi-body system softwares. The results are evaluated and compared at conclusion.

Ce travail, qui s'inscrit dans le cadre de recherches sur les surfaces à propriétés spécifiques, a porté sur le concept de l'élaboration de surfaces à mouillabilité photo-contrôlable. Le principe repose sur la création d'une couche de molécules à transition photo-induite modifiant l'état de polarisation de la surface. Pour atteindre cet objectif et compte tenu des applications potentielles, nous avons orienté nos investigations vers deux types de support : les surfaces polymère et les surfaces silicium.<br />La méthode d'élaboration sur surfaces polymère a consisté à fonctionnaliser la surface d'un film commercial de polypropylène par un traitement plasma CO2. La concentration surfacique des fonctions chimiques introduite sur la surface du film polymère a été déterminée en combinant, pour la première fois, les résultats de la spectroscopie des photo-électrons X (XPS) et ceux d'un dosage fluorimétrique à l'aide d'un spectromètre Raman. La voie d'élaboration utilisée permet, pour la première fois à notre connaissance, le greffage des chromophores uniquement sur l'extrême surface du matériau. <br />Nos résultats ont permis d'attribuer les variations réversibles de la mouillabilité des matériaux non pas à une modification de la polarité de la surface due à l'isomérisation des chromophores greffés sur la surface du film polymère, mais à une variation réversible de la morphologie de la surface due à l'isomérisation des composés azoïques diffusés dans le matériau.<br /> Dans l'objectif d'applications en microfluidique et afin d'avoir une meilleure compréhension des paramètres influençant le photo-contrôle de la mouillabilité, nous avons mis en place plusieurs voies de préparation pour permettre le greffage d'une couche moléculaire de chromophores sur la surface silicium. <br />L'ensemble de nos travaux ajouté à l'analyse des résultats tirés de la littérature a permis de contribuer à une meilleure compréhension des paramètres pouvant influencer le photo-contrôle de la mouillabilité de surface de matériaux. Ainsi, pour les surfaces siliciées, le choix du chromophore est important car pour bénéficier d'une grande variation de mouillabilité, la surface doit être composée de chromophores dont les isomères possèdent une forte différence de moment dipolaire. Un autre paramètre important semble être la compacité de la couche de chromophore greffée sur la surface silicium car plus cette couche est compacte, plus la variation de mouillabilité observée est importante.

Nanoscience dominates virtually every field of science and technology in the 21st century. Nanoparticles are of fundamental interest since they possess unique size- dependent properties (optical, electrical, mechanical, chemical, magnetic etc.), which are quite different from the bulk and the atomic state. Bimetallic nanoparticles are of particular interest since they combine the advantages of the individual monometallic counterparts. The present study focuses on bimetallic nanoparticles containing gold as one of the constituents. Au-Pd, Au-Pt and Au-Ag bimetallic/alloy nanoparticles have been prepared by four different synthetic methods, and characterised by a variety of techniques, with an emphasis on Au-Ag alloy systems in the solution phase as well as in the form of nanostructured films on solid substrates. Au- Ag alloy nanoparticles have been used to demonstrate two different applications. The first is the use of Au-Ag monolayer protected alloy clusters in demonstrating single electron charging events in the solution phase as well as in the dry state. Single electron transfer events involving nanosized particles are being probed extensively due to their potential applications in the field of electronics. The second is an analytical application, involving the use of trisodium citrate capped Au-Ag alloy hydrosols as substrates for surface enhanced Raman and resonance Raman scattering [SE(R)RS] studies. The sols have been used for single molecule detection purposes. Various organic molecules such as quinones, phthalocyanines and methyl violet have been self- assembled in a stepwise manner on the nanoparticulate as well as bulk Au, Ag and Au-Ag surfaces, and characterised extensively by spectroscopic, electrochemical and spectroelectrochemical techniques.

Graphene, a two-dimensional counterpart of three-dimensional graphite, has attracted significant interest, due to its distinctive electrical and mechanical properties, for developing electronic, optoelectronic, and sensor technologies. In general, doping of graphene is important, as it gives rise to p-type and n-type materials, and it adjusts the work function of the graphene. This adjustment is necessary in order to control charge injection and collection in devices such as solar cells and light emitting devices. Current methods for graphene doping involve high temperature process or interactions with chemicals that are not stable. Moreover, the process of transferring graphene from its growth substrate and its exposure to the environment results in a host of chemical groups that can become attached to the film and alter its electronic properties by accepting or donating electrons/holes. Intentional and controllable doping of the graphene, however, requires a deeper understanding of the impact of these groups. The proposed research will attempt to clarify the unintentional doping mechanism in graphene through adsorption or desorption of gas/vapor molecules found in standard environments. A low temperature, controllable and defect-free method for doping graphene layers will also be studied through modifying the interface of graphene and its support substrate with self-assembled monolayers (SAMs) which changes the work function and charge carriers in the graphene layer. Furthermore, current methods of chemical vapor deposition synthesis of graphene requires the film to be transferred onto a second substrate when the metal layer used for growth is not compatible with device fabrication or operation. To address this issue, the proposed work will investigate a new method for wafer scale, transfer-free synthesis of graphene on dielectric substrates using new carbon sources. This technique allows patterned synthesis on the target substrate and is compatible with standard device fabrication technologies; hence, it opens a new pathway for low cost, large area synthesis of graphene films.