Dissertations / Theses: 'Silan'

1

Klemm, Antje. "Untersuchung der bakteriellen Adhäsion auf Silan-Oberflächen." kostenfrei, 2009. http://www.opus-bayern.de/uni-regensburg/volltexte/2009/1357/.

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2

Hojdis, Nils Walter [Verfasser]. "Computersimulationen von Silica-Silan-Polymer Grenzflächen / Nils Walter Hojdis." Wuppertal : Universitätsbibliothek Wuppertal, 2015. http://d-nb.info/1076644279/34.

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3

Hofstätter, Michael. "Silicium aus der Gasphase Optimierung der Gasphasenabscheidung von Silicium aus Silan /." [S.l. : s.n.], 2002. http://deposit.ddb.de/cgi-bin/dokserv?idn=967060109.

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4

Heger, Katrin. "Oberflaechenfunktionalisierung synthetischer Kieselsaeuren: Beitrag zur Erzeugung und Charakterisierung von Silan- und Phenylgruppen auf Siliciumdioxidoberflaechen." Doctoral thesis, Universitätsbibliothek Chemnitz, 1998. http://nbn-resolving.de/urn:nbn:de:bsz:ch1-199800075.

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Die Arbeit enthaelt kurze Abrisse zum gegenwertigen Kenntnisstand bezueglich der Struktur und der Eigenschaften von amorphen Siliciumdioxiden sowie zur Erzeugung von Silan- und Phenylgruppen auf Siliciumdioxidoberflaechen. Im Mittelpunkt der Arbeit steht die Oberflaechenfunktionalisierung des Aerosil 300 aus der Gasphase bei hohen Temperaturen. Es wird die Reaktion des Wasserstoffs mit den Silanolgruppen zu Silangruppen und deren Umsetzung mit Benzol untersucht. Die IR-Spektroskopie wird zur Verfolgung des Einflusses der Reaktionsparameter (Temperatur, Zeit und Volumenstroeme der Gase) auf das Ergebnis der Funktionalisierung eingesetzt. Neben der IR-Spektroskopie wird auch die Festkoerper-NMR-Spektroskopie zur Strukturaufklaerung genutzt. Weiterhin werden die erzeugten Oberflaechengruppen quantitativ bestimmt und die molaren dekadischen Extinktionskoeffizienten fuer die Valenzschwingung der Silangruppen bei 2293 cm-1 und der Phenylgruppen bei 3068 cm-1 berechnet. Die Hydrolysebestaendigkeit sowie die thermische Stabilitaet der Oberflaechensilane und -phenyle wird ueberprueft. Außerdem werden Aussagen zu den Eigenschaften der Oberflaechen-Si-H-Bindung getroffen. Dann wird gezeigt, daß auch auf Kieselgeloberflaechen Silan- und Phenylgruppen erzeugt werden koennen.

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5

Lawrenz, Ineke [Verfasser]. "Beständigkeit des Klebeverbundes zweier Silikatkeramiken nach Klebeflächenkonditionierung mit Titantetrafluorid und einem Silan / Ineke Lawrenz." Kiel : Universitätsbibliothek Kiel, 2013. http://d-nb.info/1037109422/34.

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6

Heger, Katrin. "Oberflächenfunktionalisierung synthetischer Kieselsäuren Beitrag zur Erzeugung und Charakterisierung von Silan- und Phenylgruppen auf Siliciumdioxidoberflächen /." [S.l. : s.n.], 1998. http://www.bsz-bw.de/cgi-bin/xvms.cgi?SWB10324551.

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7

Lewin, Ingela, and Sara Rydberg. "Effekten av värmebehandlat silan på bindningsstyrkan mellan en litiumdisilikatbaserad glaskeram och ett adhesivt cement." Thesis, Malmö högskola, Odontologiska fakulteten (OD), 2011. http://urn.kb.se/resolve?urn=urn:nbn:se:mau:diva-19853.

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Vid adhesiv cementering, så kallad bonding, rekommenderar fabrikanter att glaskeramers cementeringsyta etsas innan applicering av silan. Att värmebehandla silan med respektive utan etsning, har i tidigare studier visat en höjning av bindningsstyrkan mellan olika material.Den litiumdisilikatbaserade glaskeramen IPS e.max® Press har funnits på marknaden sedan 2005 och få studier har gjorts på ytbehandlingar och dess effekter på materialet och bindningen till olika material.Syftet: att undersöka om ytbehandling med värmebehandlat silan ger en högre bindningsstyrka till adhesivt cement hos en litiumdisilikatbaserad glaskeram, jämfört med kombinationen etsning och silanisering.Material och metod: 12 litiumdisilikatbaserade keramiska block pressades. Blocken delades parvis in i sex grupper och ytbehandlades med etsmedel och/eller silan med eventuell påföljande värmebehandling.Blocken cementerades samman varpå mikrostavar sektionerades fram, som sedan termocyklades. 10 provkroppar ur varje grupp valdes ut för ett microtensile bond strength test. Frakturytorna bedömdes i mikroskop. Resultaten analyserades med one-way ANOVA, Tukey’s test samt Student’s t-test.Resultat: Resultaten visar ingen signifikans i bindningsstyrka mellan enskilda grupper oavsett ytbehandling. En statistisk signifikant skillnad (p=0,047) finns mellan grupperna med ytbehandlingen icke-etsad respektive etsad. Högsta medelvärdet uppmäter de etsade grupperna.Mellan de värmebehandlade grupperna, oavsett temperatur, uppmättes ingen statistisk signifikant skillnad på bindningsstyrkan. En höjning av temperaturen visar en numerisk ökning av medelvärdet.Slutsats: En låg signifikans kan utläsas mellan de icke-etsade och de etsade grupperna, där de etsade visar högre bindningsstyrka. Resultatet mellan grupperna gällande medelvärdet av bindningsstyrka och värmebehandling är ej av statistisk signifikans tillika jämförelse av grupper oavsett ytbehandling.

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8

Stieger, Gregor. "Covalent and heterosupramolecular interaction of ceramic particles." Stuttgart : Univ, 2002. http://www.bsz-bw.de/cgi-bin/xvms.cgi?SWB10347431.

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9

Jehander, Josefin. "Kemisk ytmodifiering av nanopartiklar avsedda för inkorporering i termoplastiska filament." Thesis, Högskolan i Borås, Akademin för textil, teknik och ekonomi, 2016. http://urn.kb.se/resolve?urn=urn:nbn:se:hb:diva-10467.

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Textilier med vatten- och smutsavvisande effekt fyller en viktig funktion inom många olika områden och branscher. Dock finns det flera allvarliga problem kopplat till produktionen och användningen utav dem. Per och polyfluoroalkylsubstanser (PFAS´s), användes länge för att erhålla den vattenavvisande effekten hos textilier. Sådana substanser har dock visat sig kunna brytas ned till persistenta miljö-och hälsoskadliga ämnen och därför omfattas de idag av både förbud och utfasningskrav i REACH, en förordning antagen för Europeiska unionen för att minimera risker kring miljö och hälsa. Trots att långa fluorerade alkylkedjor är förbjudna så används liknande men kortare alkylkedjor för att åstadkomma vattenavvisande effekt. Det finns även andra varianter på marknaden, men inga klarar att vara både slitage- och nötningståliga samt hälso- och miljöriskfria. I syfte att skapa nya hållbara alternativ är Swerea IVF del av ett projekt som syftar till att utveckla en lotusfiber. I en sådan fiber är förhoppningen att den vattenavvisande effekten skall kunna inkluderas redan under fiberspinning och på så vis resultera i mer slitagetåliga och miljövänliga textila produkter. Material med superhydrofoba ytor, så som lotusblads, har både en primär och sekundär grovlek. Därför krävs anpassning av både mikro- och nanostruktur när en sådan yta skapas. I detta examensarbete, som är en del av ovan nämnda projekt, har fokus legat vid nanostrukturen. Syftet har varit att undersöka om man kan påverka nanopartiklars dispersion i termoplastiska filament genom att modifiera dem så att de blir hydrofoba och termiskt stabila. Förhoppningen har varit att få nanopartiklarna att dispergera homogent ända ut till filamentens yta. Detta för att både ge filamentet en struktur och en potentiell sänkning av dess ytenergi. Projektet påbörjades genom litteraturstudier för att bestämma material och metoder för det experimentella arbetet. Som partikelsubstrat valdes sfäriska nanopartiklar av kiseldioxid, (AEROSIL® OX 50) med en medeldiameter av 40 nm. Som ytmodifierare valdes två typer av silaner med olika alkylkedjelängd, dels triklor(oktyl)silan och dels triklor(oktadekyl)silan. Två modifieringsreaktioner med varierande halt av ovan silaner utfördes för både typer, (6 resp. 20% (w/w) i 50 ml vattenfri toluen). Efter modifieringen analyserades nanopartiklarna genom karaktä- riseringsmetoderna: Fourier Transform Infrared Spectroscopy, FTIR, Termogravimetrisk analys, TGA, Differential Scanning Calorimetry, DSC och Kontaktvinkelmätning, (drop shape analysis), DSA. Tillsammans pekar analysernas resultat på att nanopartiklar av kiseldioxid kan uppnå god hydrofob och termiskt stabil effekt genom modifiering med båda silantyperna. Beräkningar visar dock att den kortare kedjan reagerat med högst molekylhalt. Därför valdes denna till projektets följande experiment, vilka innefattade inkludering av två procenthalter av partiklar till XPURE® Polyester 701K. För att analysera partiklarnas dispersion i de därefter extruderade filamenten utfördes Svepelektronmikroskopi, SEM över filamentens tvärsnitt. Resultaten indikerar att de hydrofobt ytmodifierade partiklarna är mer benägna att dispergera homogent ända ute vid filamentens fasgränsyta, än vad de hydrofila partiklarna är. Lotusfibern kan således vara möjlig att skapa med tillämpande av liknande principer och tekniker som i detta projekt.

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10

Heger, Katrin [Verfasser]. "Oberflächenfunktionalisierung synthetischer Kieselsäuren: Beitrag zur Erzeugung und Charakterisierung von Silan- und Phenylgruppen auf Siliciumdioxidoberflächen / Katrin Heger." Chemnitz : Universitätsbibliothek Chemnitz, 1998. http://d-nb.info/1210930692/34.

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11

Gang, Andreas. "Towards bottom-up silicon nanowire-based biosensing:." Doctoral thesis, Saechsische Landesbibliothek- Staats- und Universitaetsbibliothek Dresden, 2018. http://nbn-resolving.de/urn:nbn:de:bsz:14-qucosa-235724.

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The term "Lab-on-a-Chip" (LoC) describes highly miniaturized systems in which the functionalities of entire laboratories are scaled down to the size of transportable microchips. Particularly in the field of chemical and bio-analysis, such platforms are desired for a fast and highly sensitive sample analysis at the point of care. This work focuses on silicon nanowire (SiNW) based sensors. Innovative device fabrication concepts are developed from various directions, for a facile and reliable assembly of LoC analysis systems. Firstly, a multifunctional microfluidic set-up is developed which allows for a facile reversible sealing of channel structures on virtually any kind of substrate while maintaining the possibility of a rapid prototyping of versatile channel designs and the applicability of high working pressures of up to 600 kPa. Secondly, a 3-(triethoxysilyl)propylsuccinic anhydride (TESPSA) based surface modification strategy for the attachment of specific receptor molecules without additional binding site passivation is explored. Thirdly, bottom-up grown SiNWs are utilized for producing parallel arrays of Schottky barrier field-effect transistors (FETs) via contact printing. Using the initially developed microfluidic set-up, the concept of the TESPSA-based receptor immobilization is proved via fluorescence microscopy and by applying the SiNW FETs as biosensors. Using a receptor-analyte system based on a set of antibodies and a peptide from human influenza hemagglutinin, it is shown that antibodies immobilized with the developed method maintain the specificity for their antigens. The fourth major research field in this work is the microfluidics-based alignment of one-dimensional nanostructures and their deposition at predetermined trapping sites for reliably fabricating single NW-based FETs. Such devices are expected to provide superior sensitivity over sensors based on parallel arrays of FETs. Consequently, within this work, innovative LoC devices fabrication approaches over a broad range of length scales, from micrometer scale down to the molecular level, are investigated. The presented methods are considered a highly versatile and beneficial tool set not only for SiNW-based biosensors, but also for any other LoC application
Unter dem Begriff „Lab-on-a-Chip“ (LoC) fasst man stark miniaturisierte Systeme zusammen, die die Fähigkeiten eines ganzen Labors auf einen transportablem Mikrochip übertragen. Insbesondere im Bereich der Analyse chemischer und biologischer Proben werden solche Plattformen bevorzugt eingesetzt, da sie direkt am Ort der Probenentnahme schnelle, hoch sensible Messungen ermöglichen. Im Mittelpunkt dieser Doktorarbeit stehen Sensoren auf Basis von Siliziumnanodrähten (SiNWs). Auf verschiedenen Gebieten werden innovative Konzepte zur einfachen und zuverlässigen Herstellung von LoC Systemen entwickelt. Zu Beginn wird ein multifunktionaler Mikrofluidik-Aufbau vorgestellt, der ein einfaches reversibles Verschließen von Mikrofluidik-Kanälen auf nahezu allen möglichen Substraten erlaubt. Der Aufbau ermöglicht das schnelle Anfertigen und Testen verschiedener Kanalstrukturen sowie das Betreiben von Fluidik-Experimenten mit hohen Arbeitsdrücken von bis zu 600 kPa. Der zweite Schwerpunkt der Arbeit ist die Entwicklung einer Methode zur Funktionalisierung von Sensor-Oberflächen mittels 3-(Triethoxysilyl) Propyl Bernsteinsäure Anhydrid (TESPSA) für die Immobilisierung spezifischer Rezeptormoleküle. Bei dieser Methode entfällt die Notwendigkeit einer zusätzlichen Passivierung ungenutzter Anbindungsstellen. Des Weiteren erfolgt die Herstellung von Parallelschaltungen von Schottky-Barrieren-Feld-Effekt-Transistoren (SB-FETs) aus „bottom-up“ gewachsenen SiNWs durch mechanisches Abreiben der SiNWs vom Wachstumssubstrat auf ein Empfängersubstrat. Unter Verwendung des eingangs entwickelten Mikrofluidik-Aufbaus wird die prinzipielle Anwendbarkeit der TESPSA-basierten Rezeptor-Immobilisierung nachgewiesen, sowohl anhand von Fluoreszenzmikroskopie-Untersuchungen als auch mit Hilfe der SiNW FETs als Biosensoren. Mittels eines Rezeptor-Analyt-Systems, bestehend aus verschiedenen Antikörpern und einem Peptid des Influenzavirus A, wird gezeigt, dass Antikörper, die über TESPSA an Oberflächen gebunden werden, ihre Spezifizität für ihre Antigene beibehalten. Der vierte große Forschungsabschnitt dieser Arbeit widmet sich der mikrofluidischen Ausrichtung eindimensionaler Nanomaterialien und deren Ablage an vorgegebenen Fangstellen, wodurch eine zuverlässige Herstellung von FETs aus Einzelnanodrähten erreicht wird. Es wird davon ausgegangen, dass Einzelnanodraht-FETs gegenüber Parallelschaltungen von Nanodraht-FETs verbesserte Sensoreigenschaften aufweisen. Folglich beinhaltet diese Arbeit viele zukunftsweisende Ansätze für die Herstellung von LoC Systemen. Untersuchungen über eine Bandbreite von Längenskalen, von Mikrometer großen Strukturen bis hinab zur molekularen Ebene, werden präsentiert. Es wird davon ausgegangen, dass die vorgestellten Methoden als eine vielfältige Sammlung von Werkzeugen nicht nur bei der Herstellung von Biosensoren auf SiNW-Basis Einsatz finden, sondern ganz allgemein den Aufbau verschiedenster LoC Systeme vorantreiben

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12

Römhildt, Lotta. "Biochemical functionalization of silicon dioxide surfaces for sensing applications." Doctoral thesis, Saechsische Landesbibliothek- Staats- und Universitaetsbibliothek Dresden, 2014. http://nbn-resolving.de/urn:nbn:de:bsz:14-qucosa-148666.

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The aim of this work was to functionalize silicon dioxide surfaces with biochemical molecules in such a way that biorecognition of target molecules in solution will be possible. By introducing a tool set of different molecules and characterization methods, a more universal approach towards various biosensor setups is presented. This includes on the one hand preparation of the biosensor surfaces to allow further molecule attachment via their reactive functional groups. Secondly, the selection of chemical molecules providing suitable counterparts for abundant functional groups of potential receptors is discussed. Two detection schemes are introduced – based on an antibody to detect the antibiotic amoxicillin and aptamers to detect thrombin. The antibody was implemented in an inverse competition assay to probe such small target molecules. Antibiotic residues are often present in wastewater. Aptamers, so-called artificial antibodies, were selected as they provide many advantages over antibodies. As a model system, two different thrombin binding aptamers were chosen which allowed to perform sandwich assays as well. The protein thrombin plays an important role in the blood coagulation cascade. To probe the individual modification steps, different techniques for analysis were applied. Surface micropatterning was introduced to improve recognition of modified areas and fluorescence-to-background ratios resulting in a thrombin detection limit down to 20 pM. One important goal was the integration in ion-sensitive field-effect transistor devices. Aptamers are small in size which might enable a higher sensitivity of these devices compared to the use of antibodies because of the Debye layer thickness. As a final step, first measurements towards silicon nanowire based field-effect transistor biosensors were carried out on devices with bottom-up and top-down fabricated nanowires using both proposed receptor-analyte combinations. The potential of these devices as portable sensors for real-time and label-free biosensing is demonstrated
Ziel dieser Arbeit war es Siliziumdioxidoberflächen so mit biochemischen Molekülen zu funktional- isieren, dass die biologisch spezifische Erkennung von Zielmolekülen in Lösung möglich wird. Hier wird eine Auswahl an geeigneten Molekülen und Charakterisierungsmethoden für einen vielseitigen Ansatz gezeigt, der auf verschiedene Biosensorsysteme anwendbar ist. Das beinhaltet zum Einen die Präparation der Biosensoroberflächen, so dass die Moleküle über reaktive funktionelle Gruppen angebunden werden können. Als zweites ist die Auswahl der chemischen Moleküle wichtig, da diese die passenden Gegenstücke zu potentiellen funktionellen Gruppen der Rezeptoren darstellen. Zwei verschiedene Detektionsvarianten werden eingeführt – Antikörper gegen das Antibiotikum Amoxicillin und Aptamere gegen Thrombin. Der Antikörper wurde in einen inversen Wettbewerbsassay integriert um einen solch kleinen Ana- lyten detektieren zu können. Rückstände von Antibiotika sind häufig in Abwässern zu finden. Ap- tamere, sogenannte künstliche Antikörper, weisen gegenüber Antikörpern viele Vorteile auf. Als ein Modellsystem wurden zwei unterschiedliche Thrombin bindende Aptamere verwendet, was auch die Durchführung von Sandwich Assays ermöglichte. Das Protein Thrombin spielt eine wichtige Rolle bei der Blutgerinnung. Um die einzelnen Modifikationsschritte zu untersuchen, wurden verschiedene Charakterisierungsmethoden angewendet. Die Mikrostrukturierung der Funktionalisierung erleichterte die Erkennung der modifizierten Flächen und verbesserte das Fluoreszenz-zu-Hintergrund Verhältnis. Das führte zu einer Detektionsgrenze von 20 pM für Thrombin. Ein wichtiges Ziel dieser Arbeit war die Integration der Funktionalisierung in einen ionen-sensitiven Feldeffekttransistor. Die kleinen Aptamere könnten dabei aufgrund der geringen Debye-Schichtdicke bei diesen Sensoren eine höhere Sensitivität als mit Antikörpern ermöglichen. Zuletzt wurden erste Messungen hin zu Silizium Nanodraht basierten Feldeffekttransistor Biosen- soren mit beiden untersuchten Rezeptor-Analyt-Kombinationen durchgeführt. Sowohl die Chips mit bottom-up als auch mit top-down gewachsenen Nanodrähten zeigen dabei ihr Potential als handliche Sensoren zur markerfreien Detektion in Echtzeit

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13

Braun, Marek. "Beitrag zur physikalisch-chemischen Charakterisierung funktionalisierter SiO2-Oberflächen am Beispiel der thermodynamischen und infrarotspektroskopischen Eigenschaften von Silan- und Phenylgruppen auf Aerosil." Doctoral thesis, Universitätsbibliothek Chemnitz, 2004. http://nbn-resolving.de/urn:nbn:de:swb:ch1-200401380.

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Schwerpunkt der Arbeit ist die Übertragung thermodynamischer Betrachtungen auf Reaktionen an den Gruppen auf der amorphen Siliciumdioxidoberfläche. Aus der theoretischen Konzeption folgen Prognosen für die Abläufe und somit Aussagen für eine zielgerichtete und bewußte Prozeßsteuerung. Die stoffliche Veränderung an den Oberflächengruppen wird mit molekularen Abbildern beschrieben. Wegen des überschaubaren Reaktionsgeschehens und der Verfügbarkeit thermodynamischer Daten dient die Erzeugung von Silan- und Phenylgruppen als Beispiel. Die Modellierung der Vorgänge erfolgt in thermodynamischen Rechnungen zum Reaktionsgleichgewicht im Temperaturbereich 298 K - 1500 K. Die Beurteilung der Gleichgewichtslage beruht auf der jeweiligen molaren Freien Reaktionsenthalpie. Aus der Charakterisierung von Reaktionsgleichgewichten folgen Aussagen zu benötigten Prozeßbedingungen, bevorzugten Vertretern und zur Beeinflussung durch Nebenreaktionen. Die Modellrechnungen werden mit Experimenten kombiniert, bei denen Aerosilpreßlinge mit Wasserstoff und Benzen reagieren. Aerosil bietet wegen seiner Reinheit sowie seiner hochdispersen und röntgenamorphen Eigenschaften optimale Voraussetzungen für die analytische Charakterisierung der Reaktionsprodukte mit der Infrarotspektroskopie und der Thermischen Analyse. Da die Umsetzungen in einem Strömungsrohrreaktor stattfinden und die Gleichgewichtsthermodynamik nicht anwendbar ist, stehen die Ergebnisse der Berechnungen zur Diskussion. Die Gesamtdarstellung der Reaktionsfähigkeit beinhaltet die Charakterisierung der erzeugten Spezies an der Aerosiloberfläche. Analogiebeziehungen und Modellbetrachtungen aus der Volumenchemie führen zu den energetischen und polaren Eigenschaften der Oberflächenbindungen.

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14

Böke, Frederik Verfasser], Horst [Akademischer Betreuer] [Fischer, and Sabine [Akademischer Betreuer] Neuss-Stein. "Hydrolysestabile Bioaktivierung medizinischer Hochleistungskeramik durch Quervernetzung von RGD-Peptiden, BMP-2- und HGF-Proteinen an Silan-Monoschichten / Frederik Böke ; Horst Fischer, Sabine Neuss-Stein." Aachen : Universitätsbibliothek der RWTH Aachen, 2019. http://d-nb.info/1216177414/34.

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Böke, Frederik [Verfasser], Horst [Akademischer Betreuer] Fischer, and Sabine [Akademischer Betreuer] Neuss-Stein. "Hydrolysestabile Bioaktivierung medizinischer Hochleistungskeramik durch Quervernetzung von RGD-Peptiden, BMP-2- und HGF-Proteinen an Silan-Monoschichten / Frederik Böke ; Horst Fischer, Sabine Neuss-Stein." Aachen : Universitätsbibliothek der RWTH Aachen, 2019. http://d-nb.info/1216177414/34.

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16

Selander, Anders. "Hydrophobic Impregnation of Concrete Structures : Effects on Concrete Properties." Doctoral thesis, KTH, Brobyggnad inkl stålbyggnad, 2010. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-12179.

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Hydrophobic impregnations often referred to as water repellent agents, today mainly consisting of alkylalkoxysilanes, are often used on concrete to prolong the service life of the structure. This is accomplished by protecting the reinforcement bars from chlorides or by changing the moisture content inside. When the concrete is treated with a water repellent agent the properties of the surface layer becomes hydrophobic and thereby water droplets are stopped from entering, still allowing water vapour to pass through. This change can reduce chloride ingress and stop heavy rain from penetrating through the surface layer. This thesis presents results concerning how the properties of concrete are affected by a hydrophobic impregnation. Moisture transport and fixation in the surface layer of the concrete are studied as well as the secondary effects of more practical use such as the effect on chloride ingress, water absorption and humidity level. It also presents results on how the penetration depth and concentration of the water repellent agent (i) depend on a number of parameters, and (ii) affect the outcome of the treatment. Water repellent treatments on a number of different concrete structures in Stockholm, ranging from tunnel to high-rice building, are evaluated as well. The three most important factors for the penetration of any water repellent agent into concrete are time, porosity and degree of saturation. A semi-empirical equation is derived that gives an idea on how much these factors affect the efficient penetration depth of the water repellent agent. The depth and concentration have a major effect on the performance of the treatment. The moisture diffusion coefficient for a water repellent treated concrete is close to constant and not nearly as dependent on the relative humidity (RH) as for untreated concrete. Unlike untreated concrete, where capillary suction plays an important role for the moisture transport at high RH, the vapour transport is the dominant transport mechanism even at high RH for water repellent treated concrete. The moisture fixation is affected by a water repellent treatment and the effect is clearest at high moisture levels. The main reason for this is that the capillary porosity is affected by the treatment to a relatively high degree while the gel porosity to a large extent remains unaffected. A hypothesis is presented which suggests that the RH inside the concrete at the time of the treatment affects not only the depth and concentration but also in which range of pore radii the water repellent agent is present and active. The durability of hydrophobic impregnations can be divided into surface effects and in depth effects. The first is sensitive to the environmental and mechanical loadings and normally disappears within a year while the later can be long lasting if a sufficient depth is reached. Hydrophobic impregnations are not the answer to all problems in concrete related to moisture, but if correctly used it can prolong the service life of the structure which will lead to savings of natural resources and thus both economical and environmental savings for the community.
Vattenavvisande impregneringsmedel, som i dagsläget till största del består av alkylalkoxysilaner, används ofta på betong för att förlänga livslängden på konstruktionen. Detta syfte uppnås genom att armeringen skyddas mot klorider eller att fukthalten inuti betongen sänks. När betongen impregneras ändras ytskiktets fuktmekaniska egenskaper från hydrofila till hydrofoba vilket gör att vattendroppar kan stoppas medan vattenånga tillåts passera. Dessa förändrade egenskaper kan medföra att kloridinträngningen minskar och att kraftiga regn inte tränger genom det impregnerade skiktet. Denna avhandling presenterar resultat om hur betongen påverkas av en vattenavvisande impregnering. Fukttransport och fuktfixering i betongens ytskikt har undersökts men även sekundära effekter som kloridinträngning, vattenabsorption och förändring i fuktinnehåll vilka alla är av större praktisk nytta. Avhandlingen presenterar också resultat om vilka faktorer som påverkar impregneringens inträngningsdjup och koncentration samt vilken betydelse dessa har för funktionen. För att utvärdera impregneringars effekt i olika miljöer har ett stort antal objekt i Stockholm undersökts, innefattande olika konstruktioner från en tunnel till höghus. Impregneringens inträngningsdjup och koncentration har en avgörande betydelse för dess funktion. De tre viktigaste faktorerna för alla impregneringsmedels inträngning i betong är tid, porositet och fuktnivå. En semiempirisk ekvation har tagits fram där det framgår hur dessa tre faktorer påverkar det slutliga inträngningsdjupet för impregneringen. Till skillnad från obehandlad betong är transportkoefficienten för en impregnerad betong nästan oberoende av den relativa fuktigheten (RF) i omgivningen. Vid höga RF, där största delen av fukttransporten i obehandlad betong sker på grund av kapillärkrafter, är ångtransporten fortfarande den dominerande transportmekanismen i impregnerad betong. Fuktfixeringen i betong påverkas av en impregnering och effekten är störst vid höga RF. Det är dock tydligt att en viss mängd fukt finns inuti den impregnerade betongen. Detta kan förklaras med att största delen av kapillärporerna påverkas av impregneringen medan gelporerna förblir obehandlade. Resultaten indikerar också att fuktnivån vid impregneringstillfället avgör vilken del av porsystemet som kan behandlas och inte bara koncentrationen och inträngningsdjupet. Långtidsegenskaperna hos impregneringen kan delas upp i yt- och djupeffekt. Effekten på ytan avtar normalt sett inom ett år på grund av damm och partiklar, UV-ljus, slitage mm. Djupeffekten påverkas däremot inte av dessa faktorer och kan finnas kvar i decennier. Vattenavvisande impregneringar är inte lösningen på alla fuktrelaterade problem i betong, men om de används på rätt sätt så kan det förlänga livslängden på många konstruktioner. Detta leder till ett bättre hushållande med naturresurser och därmed både ekonomiska och miljömässiga besparingar för samhället.
QC20100715

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Lü, Runsheng. "Die Entwicklung vernetzbarer Polyolefinblends und deren Verarbeitung zu schmelzgesponnenen Elastomerfasern." Aachen : Shaker, 2003. http://deposit.d-nb.de/cgi-bin/dokserv?idn=968388639.

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18

Oliveira, Aline Cristina Maia de [UNESP]. "Avaliação dos parâmetros de processo de reticulação do polietileno de baixa densidade." Universidade Estadual Paulista (UNESP), 2011. http://hdl.handle.net/11449/94445.

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Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)
O presente trabalho aborda as condições de reticulação do polímero termoplástico polietileno e, para isso, foram avaliadas diferentes temperaturas de processo (60 e 90°C), bem como diferentes tempos de permanência em imersão em banho termostatizado (1, 3, 6 e 9 horas). Esta avaliação foi realizada a partir dos ensaios de teores de gel e fator de uptake, de massa específica, de calorimetria exploratória diferencial (DSC), de análise termogravimétrica (TGA), de espectrofotometria no infravermelho com transformada de Fourier (FT-IR) e de ensaios de tração. Desta forma, o grau de reticulação do polietileno de baixa densidade reticulado em água, foi correlacionado com sua morfologia, com seu desempenho térmico e mecânico. Os resultados mostraram que o teor de gel do polietileno reticulado aumentou com o aumento da temperatura e do tempo de exposição desta matriz polimérica em água, sendo que, este aumento ocorreu de forma significativa até 3 horas de exposição, não sendo observados ganhos significativos na formação de ligações cruzadas após este período
The present work deals with the crosslink conditions of polyethylene polymer using different process temperatures (60 and 90°C). For this different water immersion times in thermostated bath (1, 3, 6 and 9 hours) have been analyzed by using gel content and uptake factor, density tests, dynamic scanning calorimetric analyses (DSC), thermogravimetric analysis (TGA), infrared spectroscopy (FT-IR) and tensile tests. This way, it was evaluated the degree of crosslinking of low density polyethylene crosslinked into water, and these parameters were correlated with the morphology and its thermal and mechanical performance. According to found results, it was observed that the gel content of polyethylene crosslinked increased with increasing of exposition temperature and time of this polymeric matrix in water, therefore, this increase was significantly up to 3 hours of exposition, not being observed significant gains in crosslinking density after this time

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Oliveira, Aline Cristina Maia de. "Avaliação dos parâmetros de processo de reticulação do polietileno de baixa densidade /." Guaratinguetá : [s.n.], 2011. http://hdl.handle.net/11449/94445.

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Resumo: O presente trabalho aborda as condições de reticulação do polímero termoplástico polietileno e, para isso, foram avaliadas diferentes temperaturas de processo (60 e 90°C), bem como diferentes tempos de permanência em imersão em banho termostatizado (1, 3, 6 e 9 horas). Esta avaliação foi realizada a partir dos ensaios de teores de gel e fator de uptake, de massa específica, de calorimetria exploratória diferencial (DSC), de análise termogravimétrica (TGA), de espectrofotometria no infravermelho com transformada de Fourier (FT-IR) e de ensaios de tração. Desta forma, o grau de reticulação do polietileno de baixa densidade reticulado em água, foi correlacionado com sua morfologia, com seu desempenho térmico e mecânico. Os resultados mostraram que o teor de gel do polietileno reticulado aumentou com o aumento da temperatura e do tempo de exposição desta matriz polimérica em água, sendo que, este aumento ocorreu de forma significativa até 3 horas de exposição, não sendo observados ganhos significativos na formação de ligações cruzadas após este período
Abstract: The present work deals with the crosslink conditions of polyethylene polymer using different process temperatures (60 and 90°C). For this different water immersion times in thermostated bath (1, 3, 6 and 9 hours) have been analyzed by using gel content and uptake factor, density tests, dynamic scanning calorimetric analyses (DSC), thermogravimetric analysis (TGA), infrared spectroscopy (FT-IR) and tensile tests. This way, it was evaluated the degree of crosslinking of low density polyethylene crosslinked into water, and these parameters were correlated with the morphology and its thermal and mechanical performance. According to found results, it was observed that the gel content of polyethylene crosslinked increased with increasing of exposition temperature and time of this polymeric matrix in water, therefore, this increase was significantly up to 3 hours of exposition, not being observed significant gains in crosslinking density after this time
Orientador: Edson Cocchieri Botelho
Coorientador: Antonio Fernando Branco Costa
Banca: Luiz Claudio Pardini
Banca: Michelle Leali Costa
Mestre

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Garcia, Bruno Pienis. "Associação de taninos e silano na passivação de aço galvanizado." reponame:Biblioteca Digital de Teses e Dissertações da UFRGS, 2017. http://hdl.handle.net/10183/165150.

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A proteção contra a corrosão do aço galvanizado com um tratamento via cromatização, apesar de apresentar desempenho superior à outras alternativas, gera efluentes tóxicos ao meio ambiente e em especial aos seres humanos. Dentre as alternativas apresentadas até o presente momento, que incluem diversos tipos de tratamentos para esse substrato, um deles é o revestimento com silanos. Apesar desse revestimento ter um satisfatório desempenho, vem se utilizando incorporações em seu preparo, para se potencializar seu desempenho. A incorporação escolhida nesse trabalho foi a do tanino, um inibidor de corrosão natural, extraído de vegetais. O objetivo desse trabalho é avaliar um revestimento do silano Ortossilicato de tetraetila (TEOS) junto de um tanino para o aço galvanizado destinado a aplicações onde não há pintura. Essa sinergia deve proteger a superfície até que o zinco consiga de forma natural desenvolver sua pátina protetora, formando uma barreira entre substrato e eletrólito. Foram revestidas chapas de aço galvanizado com períodos de imersão que variaram entre 2 e 10 minutos, com soluções na concentração de tanino de 2g/L e 10g/L com diferentes valores de pH, em uma solução previamente preparada de TEOS em concentração de 2%, água 49% e etanol 49%. Realizou-se análise comparativa entre os diferentes parâmetros de tratamento proposto neste trabalho com aço galvanizado somente desengraxado e aço galvanizado cromatizado nas seguintes técnicas: espectroscopia de impedância eletroquímica, polarização potenciodinâmica, microscopia eletrônica de varredura acoplada a espectroscopia de energia dispersiva, e ensaios de corrosão acelerada em câmara úmida e névoa salina. Os resultados apresentados indicam que diferentes concentrações de tanino e tempos de imersão não são significativos para causar diferenças relevantes entre os desempenhos e que os substratos tratados demonstraram um desempenho superior comparado às amostras que não tinham nenhum tipo de tratamento e inferiores às amostras cromatizadas.
The corrosion protection of galvanized steel with a chromatized treatment, despite superior performance to other alternatives, generates effluents toxic to the environment and especially to humans. Among the alternatives presented to date, which include several types of treatments for this substrate, one of them is the coating with silanes. Although this coating has a satisfactory performance, it has been using incorporations in its preparation, to enhance its performance. The incorporation chosen in this work was that of tannin, a natural corrosion inhibitor, extracted from plants. The objective of this work is to evaluate a coating of silane tetraethyl orthosilicate (TEOS) with tannin for galvanized steel, for applications where there is no paint. This synergy should protect the surface until zinc can naturally develop its protective patina, forming a barrier between substrate and electrolyte. Galvanized steel plates were coated with immersion times ranging from 2 to 10 minutes, with solutions at tannin concentration of 2 g/L and 10 g/L with different pH values, in a previously prepared solution of TEOS at a concentration of 2% , 49% of water and 49% of ethanol. A comparative analysis was performed between the different treatment parameters proposed in this work with galvanized steel only degreased and galvanized steel chromatized in the following techniques: electrochemical impedance spectroscopy (EIE), potentiodynamic polarization, scanning electron microscopy coupled to dispersive energy spectroscopy, and corrosion tests accelerated in humid chamber and saline mist. The results indicated that different concentrations of tannin and immersion times are not significant to cause relevant differences between the performances and that the substrates demonstrated superior performance compared to the samples that had no type of treatment, and inferior to the samples chromatized.

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Johnsson, Lisa, and Veronica Karlberg. "Å ena sidan…men å andra sidan." Thesis, Högskolan i Borås, Institutionen för Pedagogik, 2008. http://urn.kb.se/resolve?urn=urn:nbn:se:hb:diva-18771.

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BAKGRUND: Bakgrunden belyser, varvat med litteratur och aktuell forskning, vad ettåtgärdsprogram är, för- och nackdelar samt hur de upprättas. En debatt kringspecialpedagogik och specialpedagogiska insatser följer upp avsnittet medåtgärdsprogram. Detta dilemmat belyses utifrån fyra forskares syn inomområdet.SYFTE: Studiens syfte är att undersöka förekomsten av åtgärdsprogram samtförskollärares åsikter kring dessa i de kommunala förskolorna i Varbergskommun.METOD: Detta är en kvantitativ studie och redskapet som användes var två olikaenkäter. Enkäterna skickades ut till 18 rektorer i de kommunala förskolorna iVarberg samt till 42 utlottade förskollärare.RESULTAT: Utav de 1429 barn som studien omfattar har 19 barn ettåtgärdsprogram. Utav de undersökta bakgrundsfaktorerna är kön densom har störst påverkan över vilka barn som har ett åtgärdsprogram.Gällande de undersökta bakgrundsfaktorerna kön, ålder och diagnosskiljer sig pedagogernas åsikter med rektorernas svar avsevärt.Studien belyser också förskollärarnas åsikter kring åtgärdsprogram,där de instämmer mer i fördelarna än nackdelarna.
Uppsatsnivå: C

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Gau, David. "Synthèse et réactivité des sila-ylures de phosphonium." Toulouse 3, 2011. http://thesesups.ups-tlse.fr/1460/.

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L'objectif principal de cette thèse est l'étude d'espèces siliciées hautement réactives stabilisées par coordination d'un ligand phosphine. Dans un premier chapitre, une étude bibliographique permet de faire le point sur les différents modes de stabilisation des silylènes ainsi que sur leurs propriétés chimiques. Le deuxième chapitre concerne la synthèse d'un sila-ylure de phosphonium dont la structure a été déterminée par diffraction des rayons-X. Cette structure est très différente de celles des analogues carbonés, les réactifs de Wittig. En particulier, le centre silicié est fortement pyramidalisé traduisant une absence de délocalisation de la paire libre du silicium contrairement aux ylures de carbone dont la liaison P-C présente un certain caractère [pi]. Le troisième chapitre traite de la réactivité des sila-ylures de phosphonium. Avec un aldéhyde, ils réagissent de façon similaire aux analogues carbonés et la première réaction de type sila-Wittig (formation d'un silène et d'un oxyde de phosphine) a été mise en évidence. Des études mécanistiques (théoriques et spectroscopiques) montrent que le mécanisme de cette réaction est différent de celui de la réaction de Wittig classique. En particulier, la première étape procède via une cyclo-addition [2+1] concertée, sur le centre silicié, démontrant que les sila-ylures de phosphonium se comportent comme des silylénoïdes nucléophiles. Ainsi, des silirènes hypervalents ont été obtenus par réaction avec des acétyléniques via une cyclo-addition [2+1] impliquant le centre silicié. Ces silirènes à température ambiante se réarrangent de façon diastéréosélective pour conduire à des phosphines P-chirales originales. La synthèse d'un disilyne (Si=Si) stabilisé par des ligands phosphines est décrite dans le quatrième chapitre. Ce dérivé réagit à température ambiante avec quatre équivalents de CO2 conduisant à la formation de CO et d'un disilicate original. Dans le dernier chapitre, l'introduction d'un carbène en [alpha] de la fonction sila-ylure nous a permis d'isoler un dérivé à triple liaison Si=C, un silyne, stabilisé par un ligand phosphine. Il s'agit là du premier exemple d'alcyne hybride organique(C)-inorganique(Si). L'étude de sa réactivité montre que le centre carboné de la triple liaison Si=C se comporte comme un carbène singulet
The main objective of this Thesis is the study of highly reactive silicon species stabilised by the coordination of phosphine ligand. In the first chapter, a bibliographic study provides an update on the different methods of stabilising silylene and their chemicals properties. The second chapter concerns the synthesis of a phosphonium sila-ylide whose the structure has been determined by X-Ray diffraction. This structure is very different to those of analogous carbons, the Wittig reactifs. In particular, the silicon center is strongly pyramidalized representing the absence of delocalisation of the silicon lone pair in contrast to the carbon ylides whose the P-C bond present some [pi]-caracters. The third chapter discusses the reactivity of the phosphonium sila-ylides. With an aldehyde, it reacts in a similar way to carbon analogous and the first sila-Wittig reaction (formation of a silene and phosphine oxyde) has been brought to light. Some mechanistic studies (theoretical and spectroscopic) show that the mechanism of this reaction is different from that of a classical Wittig reaction. In particular, the first step proceeds via a [2+1] concerted cyclo-addition, on the silicon center, demonstrating that the phosphonium sila-ylide behave like nucleophilics silylenoïdes. In this way some hypervalentes silirenes have been obtained by reaction of acetylenics compounds via a [2+1] cyclo-addition involving the silicon centre. These silirenes rearrange themselves at room temperature in a diastereoselective way to lead to original P-chirals phosphines. The synthesis of disilyne (Si=Si), stabilised by phosphine ligands is described in the fourth chapter. This compound reacts at room temperature with four CO2 equivalents, to form CO and an original disilicate. In the last chapter, the introduction of a carbene in an [alpha] position of the sila-ylide function allows us to isolate a triple bond derivative Si=C, a silyne which is stabilized by a phosphine ligand. It's the first example of organic(C)-inorganic(Si) hybride alkyne. The study of this reactivity demonstrates that the carbon center of the triple bond Si=C behaves like a singular carbene

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Murillo, Gomez Fabian de Jesus 1987. "Avaliação da união cerâmica-vítrea/cimento-resinoso usando diferentes soluções contendo silano = Evaluation of glass-ceramic/resin-cement interface using different silane-containing solutions." [s.n.], 2015. http://repositorio.unicamp.br/jspui/handle/REPOSIP/288150.

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Orientador: Mario Fernando de Goes
Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Odontologia de Piracicaba
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Resumo: O objetivo deste estudo foi avaliar a interação de diferentes soluções contendo silano, com cerâmica vítrea e cimentos resinosos por meio da resistência de união por microcisalhamento e avaliação morfológica da fratura. Este estudo foi separado em dois capítulos. No capítulo 1 foi verificada a influência de quatro soluções contendo silano (solução convencional, solução convencional seguida da aplicação de um sistema adesivo convencional, sistema adesivo universal contendo silano e um primer universal para materiais cerâmicos contendo silano) e a influência do uso ou não do condicionamento prévio da cerâmica com ácido fluorídrico na resistência de união entre uma cerâmica vítrea e um cimento resinoso convencional, após 24h. A análise morfológica da fratura foi avaliada com microscópio eletrônico de varredura. Todos os dados foram submetidos à análise de variância a dois fatores e teste de Tukey (?=0.05). Os resultados mostraram que o condicionamento prévio da cerâmica com ácido fluorídrico foi um fator determinante na obtenção de valores estatisticamente significativos na resistência de união entre ela e o cimento resinoso. A solução de silano convencional foi o único tratamento que proporcionou valores significativamente maiores de resistência de união sem a aplicação do condicionamento prévio na cerâmica vítrea. Todas as soluções proporcionaram resistência de união estatisticamente superior quando o ácido fluorídrico foi usado previamente em relação ao grupo de cerâmicas só jateadas com óxido de alumínio. Os valores foram diferentes estatisticamente entre as soluções, sendo a solução convencional de silano a mais efetiva. Padrão de fratura coesiva no cimento foi associado com valores maiores, enquanto que falha adesiva foi associada com menor resistência de união. No capítulo 2, o objetivo foi avaliar a interação das mesmas soluções contendo silano com cinco cimentos resinosos, três convencionais (Rely X Ultimate, Rely X ARC e Variolink II) e dois autoadesivos (Bifix e Rely X Unicem 2). A resistência de união por microcisalhamento e o tipo de fratura foram avaliados. Os valores foram submetidos à análise estatística a dois fatores e ao teste de Tukey (?=0.05). Os resultados mostraram que a resistência de união foi maior quando a cerâmica foi tratada com a solução convencional de silano para todos os cimentos. A maioria dos cimentos apresentou resistência de união sem diferença estatística quando usados junto com o sistema adesivo universal e o primer cerâmico, exceto para o Bifix e Rely X ARC. Nas fotografias em MEV observaram-se áreas de polimerização incompleta nos casos do Bifix e Rely X ARC. Os grupos com melhor resistência de união apresentaram maior prevalência de fratura coesiva no cimento, enquanto que os grupos com menores valores de resistência de união apresentaram maior prevalência de fraturas adesivas e maior variabilidade do tipo de falha no mesmo grupo. Como conclusão observou-se que as soluções que combinam silano com outros componentes podem melhorar a adesão entre a cerâmica vítrea e o cimento resinoso sempre que utilizadas em cerâmicas vítreas previamente condicionadas, mas o seu efeito positivo é menor do que o obtido pela solução convencional de silano. Além disso, a interação dessas soluções não convencionais com os cimentos resinosos é material dependente já que nem todos os cimentos avaliados foram afetados
Abstract: The aim of this study was to evaluate the interaction of different silane-containing solutions, with glass ceramic and resin cements by performing a µSBS and failure evaluation. This investigation was separated in two chapters. Chapter 1 verified the influence of four silane-containing solutions (conventional solution, conventional solution followed by a conventional adhesive system, silane-containing universal adhesive system and a silane-containing universal ceramic primer) and previous hydrofluoric acid etching on µSBS of glass ceramic and one conventional resin cement after 24 hours storage. Morphological failure analysis was assessed with a scanning electron microscope. All data was submitted to two-way ANOVA and Tukey test (p<0.05). Results showed that hydrofluoric acid etching was determining to increase µSBS. The only solution that increased significantly µSBS mean value without previous hydrofluoric acid etching was the sole-silane solution. All tested solutions increased µSBS when ceramic was previously etched but with statistical differences between them, being the most effective the sole-silane solution. Cohesive failure in resin cement was associated with higher µSBS values, while ceramic/cement adhesive failure was correlated to lower mean values. In chapter 2 the purpose was to evaluate the interaction of the same silane solutions with five resin cements, three conventional (Rely X Ultimate, Rely X ARC e Variolink II) and two self-adhesive (Bifix e Rely X Unicem 2). Also µSBS test and failure evaluation were performed and results analyzed by ANOVA two-way and Tukey test (p<0.05). Results showed that µSBS was higher when ceramic was treated with the sole-silane solution for all cements. Most of cements showed statistically similar mean values when treated with the universal adhesive and the universal ceramic primer with the exception of BiFix and RelyX ARC. SEM images revealed some incomplete polymerization areas for those cases. Likewise groups that performed better showed more prevalence of cohesive failure in resin cement while groups that presented lower mean values showed more prevalence of adhesive failure and more failure type variability. As conclusion, it was observed that solutions combining silane with other components could improve adhesion between glass ceramic and resin cement whenever employed on previously conditioned ceramics, but their positive effect is lower than the one produced by the sole-silane solution. Furthermore, interaction of those non-conventional silane-solutions with resin cements may be material dependent as not all cements tested were negatively affected
Mestrado
Materiais Dentarios
Mestre em Materiais Dentários

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Bertuoli, Paula Tibola. "Desenvolvimento e caracterização de uma tinta em pó base poliéster contendo montmorilonita funcionalizada com silano." reponame:Repositório Institucional da UCS, 2014. https://repositorio.ucs.br/handle/11338/826.

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Dentre os métodos empregados para a proteção à corrosão de materiais metálicos os revestimentos orgânicos vêm sendo muito utilizados devido a sua facilidade de aplicação e custos razoáveis. A propriedade de barreira dos revestimentos orgânicos pode ser melhorada com a incorporação de cargas adequadas, tais como nanocargas que, mesmo em baixas concentrações, apresentam propriedades de barreira superiores às cargas convencionais. A montmorilonita (MMT) é a fase inorgânica mais utilizada na obtenção de nanocompósitos poliméricos. Para melhorar a compatibilidade e dispersão da argila na resina polimérica, muitos pesquisadores têm realizado o processo de funcionalização da argila utilizando silano. O presente trabalho tem como objetivo desenvolver e caracterizar uma tinta em pó base poliéster contendo diferentes teores da argila montmorilonita sódica (MMT-Na+) modificada com o silano 3-aminopropiltrietoxisilano (γ-APS). A argila modificada com silano (S-MMT) ou a MMT-Na+ foi incorporada numa formulação padrão de tinta em pó base poliéster nas proporções de 2, 4 e 8% (m/m). A incorporação da argila na tinta ocorreu no estado fundido (extrusão). As argilas, a tinta em pó e o revestimento após a cura foram analisados empregando diferentes técnicas de caracterização, tais como difração de raios X (DRX), espectroscopia de infravermelho por transformada de Fourier (FTIR), análise termogravimétrica (TGA), calorimetria exploratória diferencial (DSC), microscopia eletrônica de varredura (MEV), microscopia óptica (MO). As tintas em pó foram aplicadas sobre painéis de aço carbono por pulverização eletrostática. O efeito da incorporação de diferentes teores da argila modificada e não modificada nas propriedades físicas e de proteção à corrosão das tintas foram avaliadas empregando ensaios de medida de brilho, aderência, flexibilidade, resistência ao impacto, potencial de circuito aberto (OCP), imersão, impedância eletroquímica (EIS) e exposição à névoa salina. Através do DRX foi confirmada a modificação e a intercalação de uma bicamada de moléculas de aminopropil no espaçamento interlamelar da argila. A S-MMT apresentou uma maior perda de massa do que a MMT-Na+ devido à presença de silano na sua estrutura. A MMT-Na+ se apresentou na forma de grandes aglomerados irregulares que se tornaram menores e mais finos após sua modificação com silano. Nas tintas contendo os diferentes teores de argila (MMT-Na+ ou S-MMT) não foi constatada a esfoliação da argila, sendo obtido um microcompósito. A partir da caracterização térmica da tinta em pó constatou-se que os revestimentos contendo a S-MMT apresentaram menor estabilidade térmica que os demais revestimentos devido à presença do modificador orgânico. A presença da argila MMT-Na+ ou S-MMT (com exceção de 4% (m/m) da S-MMT) reduziu a energia liberada no processo de reticulação. Para todos os revestimentos contendo argila foi constatado o aumento da dureza superficial do revestimento e a redução de brilho com o aumento do teor de argila, sendo este efeito mais pronunciado com a adição de 8% (m/m) de MMT-Na+. A aderência do revestimento ao substrato e a flexibilidade do revestimento não foram alteradas pela presença da argila, porém os revestimentos contendo a S-MMT apresentaram melhores resultados quanto à resistência ao impacto que os revestimentos contendo a argila MMT-Na+. Tanto nos ensaios eletroquímicos como no de exposição à névoa salina a modificação da argila com o silano resultou em revestimentos com melhor desempenho à corrosão que os revestimentos contendo a argila não modificada. Contudo, a propriedade de proteção à corrosão dos revestimentos contendo argila não foi superior ao revestimento isento de argila.
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Fundação de Amparo à Pesquisa do Estado do Rio Grande do Sul, FAPERGS
Among the methods used for corrosion protection of metal materials the organics coatings have been widely used due to their ease of application and reasonable costs. The barrier property of the organic coatings can be improved by incorporation of appropriate fillers such as nanofillers that even in low concentrations show superior barrier properties to conventional fillers. The montmorillonite (MMT) is the inorganic phase more used to prepare polymer nanocomposites. To improve the compatibility and dispersion of the clay in a polymer resin, many researchers have performed the functionalization process of the clay using silane. This study aims to develop and characterize a polyester based powder coating containing different amounts of sodium montmorillonite (MMT-Na+) modified with the silane 3-aminopropyltriethoxysilane (γ-APS). The clay modified with silane (S-MMT) or MMT-Na+ clay were incorporated into a standard commercial formulation of a polyester based powder coating on the ratios of 2, 4 and 8 wt%. The incorporation of clay into the paint was in the molten state (extrusion). The clays, the powder coating and coating after curing were analyzed using different characterization techniques such as X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), thermal gravimetric analysis (TGA), differential scanning calorimetry (DSC), scanning electron microscopy (SEM) and optical microscopy (MO). The powder coatings were applied on carbon steel panels by electrostatic method. The effect of incorporating different amounts of modified and unmodified clay on the physical properties and corrosion protection of the coatings obtained were evaluated using techniques such as gloss measurement, adhesion, flexibility, impact resistance, open circuit potential (OCP), immersion and electrochemical impedance spectroscopy (EIS) in sodium chloride solution and exposure to salt spray. XRD results confirmed the modification and intercalation of a bilayer of aminopropyl molecules in the interlayer spacing of the clay. By thermal analysis the S-MMT clay showed greater loss greater than the MMT-Na+ clay due to the presence of silane in their structure. The MMT-Na+ are presented in the form of large irregular agglomerates that have become smaller and thinner after its modification with silane. In the coatings obtained by incorporating different concentrations of MMT-Na+ or S-MMT it was not detected the exfoliation of clay, characterizing a microcomposite. Through of the thermal characterization of the powder paint it was found that the coatings containing S-MMT clay showed lower thermal stability than other coatings due to the presence of the organic modifier. The presence of MMT-Na+ or S-MMT clay (except 4 wt% of S-MMT clay) reduced the energy released in the process of crosslinking. The surface hardness of the coating was increased and the brightness was decreased with increasing clay content and this effect was most pronounced with the addition of 8 wt% of MMT-Na+. The adhesion of the coating to the substrate and the flexibility of the coating were not changed by the presence of clay, but the clay coatings containing S-MMT showed better results than coatings containing MMT-Na+ regarding the impact resistance. Both electrochemical and exposure to salt spray tests the silane modified clay resulted in coatings with better corrosion performance than those coatings containing the unmodified clay. However, the corrosion protection of the coatings containing montmorillonite was not superior to the coating free of clay.

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Mudry, Guillermo Alejandro. "Revestimentos de silanos obtidos sobre aço carbono e sua utilização como agentes promovedores de adesão em uniões aço-resina epóxi." reponame:Biblioteca Digital de Teses e Dissertações da UFRGS, 2011. http://hdl.handle.net/10183/61013.

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A utilização de silanos como agentes promovedores de adesão demonstrou ser uma solução útil para a união entre materiais dissimilares, incrementando a adesão e aumentando inclusive a resistência a corrosão entre os mesmos . A utilização destes agentes como promovedores de adesão, sobre diferentes combinações de materiais, continua sendo estudada atualmente. Este trabalho teve como objetivo avaliar a capacidade de diferentes tipos de silanos como agentes promovedores de adesão. tanto funcionais como não funcionais, na união entre aço SAE 1060 e resina epóxi. Para isto, foram primeiramente obtidos filmes de silano sobre amostras de aço através de diferentes tratamentos. Estes filmes obtidos foram caracterizados por meio de diferentes técnicas. Foram realizados testes de aderência através do método especificado pela norma ASTM D3359 para avaliar a resistência de adesão dos diferentes filmes ao substrato. As amostras testadas foram analisadas através de microscopia eletrônica de varredura (MEV). Também, foram realizadas análises de espectroscopia de energia dispersiva (EDS) sobre as mesmas amostras, permitindo obter outras características dos filmes de silano formados. Os tratamentos que apresentaram melhores resultados na caracterização em MEV/EDS foram escolhidas para a preparação dos corpos de prova de uniões com resina epóxi. Estas uniões foram utilizadas para realizar testes de adesão do tipo arrancamento de modo a avaliar o efeito dos tratamentos com silano na resistência de adesão da união entre o substrato de aço e a resina epóxi. Os resultados dos testes de arrancamento permitem afirmar que existe uma melhoria na resistência de adesão com um dos tratamentos com silano sobre o substrato de aço seguido de revestimento com resina epóxi. A utilização de tratamentos com silanos mostram-se promissoras para esta aplicação.
The use of silanes as adhesion enhancer agent proved to be a useful solution for the union of dissimilar materials, increasing the bond strength between them, also increase the corrosion resistance. The use of these agents as adhesion enhancer, with different materials combination, is still being studied today. The aim of this work was to evaluate the ability of different silanes as adhesion agent promoters in joints of SAE 1060 steel and epoxy resin; both functional and not functional silanes. At the beginning and for this purpose were different types of treatments used to obtain silane films on steel samples. Different techniques were used to characterize these films. To evaluate the bond strength adhesion test where performed according to the ASTM D3359 standard. Samples were analyzed with scanning electron microscope (SEM). Energy-dispersive spectroscopy (EDX) analyses were also performed on the same sample allowing to obtain others characteristics of the silane films formed. The treatments that have shown a better performance in the SEM/EDX analyses were selected to make steel and epoxy resins joint samples. These specimens were used to perform pull-out type adhesion test to evaluate the effect of the silanes treatments in the bond strength of steel and epoxy resin joints. The results of de pull-out test indicate that the use of silane improves the bond strength of steel and epoxy resin joints. The use of silane treatments has shown promising results for this application.

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26

Solala, Arvidsson Anna-Vera. "Den andra sidan." Thesis, KTH, Arkitektur, 2015. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-168589.

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Det här projektet handlar om närmandet. Om att närma byggnaden som hanterar våra döda. Varken tvinga, skrämma eller försköna. Det är en byggnad som börjar och slutar. En skulpturerad byggnadskropp med ett logistiskt flöde och rytmisk struktur. Förslaget är ett försök till ett sakta synliggörande. Synlig för att byggnaden sträcker ut sig och syns. Synlig för att du tilltåts titta in. Synlig för att du kan passera genom dess byggnadselement. Det är en skulptur av linjär form i ett landskap mellan vardag och död. En modern industri, en värdig arbetsplats, en byggnad av tyng, en byggnad som stödjer. Det ofrånkomliga har tagit fysiskt gestalt. Det har inte bäddats in, utan tar plats, rakt på plats. En uppbruten gestaltning för en splittrad själ. Ett gränsland mellan det som lever och det som passerat, till den andra sidan.
This project investigates how to approach the occupation that takes care of the deceased, to near and to border on the industry without intruding. It’s an attempt to disclose gradually, neither by intimidating anyone nor by harmonizing the reality. This crematorium is a linear building that has a beginning and an end. It is a sculptured construction with a logistical flow and rhythmic structure. Norra Begravningsplatsen in Solna is a dual place where the contrast between industry, housing, grief, work and peace meet. The centerpiece of this meeting takes place on the lot where the crematorium is placed. The experience of the place as bicameral, neglected and concealed, despite all the different activities it touches, initiated the design where the desire was to create a building with a direction. Nevertheless the place and the program deal with contrasts. It is about the contrasting relation between someone's everyday life and another’s grief. It is the encounter between the living and the dead. The building stands both symbolically and physically the boundary between industry and cemetery. It becomes a transition and it becomes a flow in a shape of architecture. In the context of the site, the building makes it self apparently visible where its volume reaches out and takes place on a broad area of the given lot. There is a possibility to look in to the building and observe the process if wanted and there are plenty of places around the building where one can rest, take cover for the rain or just lean against a comforting wall. The building has several openings and ways to pass through its components, where the divided structure as a whole distracts the mind of a passing. This project is an attempt to defuse the tension that the building has in the society of today. It strives to be a modern industry, a dignified place to work, a building of weight with an aim of supporting the bereaved that surrounds it. The inevitable has taken physical form in the building; it has not been embedded and covered - it takes place straight on the spot. It is a broken design for a broken soul, a borderland between the living and that, which has passed to the other side, past the line.

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Queiroz, Daniely Ferreira de. "Nanopartículas magnéticas de ferritas recobertas com sílica e funcionalizadas com vinil silano." Universidade de São Paulo, 2017. http://www.teses.usp.br/teses/disponiveis/75/75134/tde-04082017-153036/.

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Com o desenvolvimento da nanociência e da nanotecnologia, as nanopartículas magnéticas vêm sendo cada vez mais gerado interesse devido as inúmeras possíveis aplicações na área de catálise, diagnóstico, pigmentos, sensores, etc. Atualmente, as nanopartículas com potencialidade de aplicação em biomedicina que pode se destacar os as ferritas magnéticas os quais apresentam comportamento superparamagnético a temperatura ambiente. Além dos ligantes funcionais, as nanopartículas magnéticas são geralmente recobertas com polímeros orgânicos ou inorgânicos, destacando-se a sílica, nessa última classe. O sistemas as nanopartículas magnéticas recobertas com sílica formando um sistema casca-caroço, possibilita que o núcleo magnético se mantenha protegido por uma camada polimérica que pode conter grupos funcionais ativos, formando hidridos orgânicos-inorgânicos que devido a sua propriedade hidrofóbica ou hidrofílica dependendo da natureza do ligante de modificação de superfície. Este trabalho foi desenvolvido com intuito de obter nanopartículas magnéticas de ferrita MFe2O4, com (M= Fe, Co, Ni e Cu) com controle de tamanho, forma, composição química e estrutural, dos quais foram sintetizados pelo método de decomposição térmica utilizando diferente precursores metálicos para adequação das melhores condições de síntese. As ferritas magnéticas foram recobrimento com sílica, modificando da superfície da partícula e possibilitando caráter hidrofílico ao sistema casca-caroço, apresentando uma melhor estabilidade coloidal em dispersão aquosa devido a presença de grupos silanois na superfície, bem como uma recobrimento uniforma com apenas um núcleo magnético sem formação de aglomerados. A funcionalização com o grupo o trietoxivinilsilano, através de reações de condensação via catálise básica ou ácida, formou uma rede polimérica Si-O-Si, sendo que a presença do grupo vinil (-CH=CH2) livre na a superfície do sistema casca-caroço foi evidenciado através da técnica de FTIR. Portanto foi possível a obtenção de um sistema hibrido orgânico-inorgânico com a superfície contendo grupo que podem ser reativos, abrindo a possibilidade da utilização deste material para futuros testes de aplicações como sensor multifuncional.
In recent decades the development of nanoscience and nanotechnology, magnetic nanoparticles have been increasingly generated interest due to the numerous possible applications in the field of catalysis, diagnosis, pigments, sensors, etc. Currently, the nanoparticles with potential of application in biomedicine that can stand out the magnetic ferrites which have superparamagnetic behavior at room temperature. In addition to the functional binders, magnetic nanoparticles are generally coated with organic or inorganic polymers, especially silica in the latter class. The magnetic nanoparticle systems covered with silica forming a shell-core system allow the magnetic core to remain protected by a polymeric layer that may contain active functional groups, forming organic-inorganic hydrides that due to its hydrophobic or hydrophilic property depending on the nature of the surface modifying binder. This work was developed to obtain magnetic nanoparticles of MFe2O4 ferrite, with (M = Fe, Co, Ni and Cu) control of size, shape, chemical and structural composition, of which were synthesized by the thermal decomposition method using different precursors to suit the best conditions of synthesis. The magnetic ferrites were coated with silica, modifying the surface of the particle and allowing a hydrophilic character to the shell-core system, presenting a better colloidal stability in aqueous dispersion due to the presence of silane groups on the surface, as well as a uniform coating with only one magnetic core without formation of agglomerates. The functionalization with the triethoxyvinylsilane group, through condensation reactions via basic or acid catalysis, formed a Si-O-Si polymer network, and the presence of the free vinyl group (-CH=CH2) on the shell surface was observed by FTIR technique. Therefore, it was possible to obtain an organic-inorganic hybrid system with the surface containing the reactive group, opening the possibility of using this material for tests of future applications as multifunctional sensor.

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Mierse, Emma. "På andra sidan vattnet." Thesis, KTH, Arkitektur, 2015. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-168746.

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PÅ ANDRA SIDAN VATTNET Byggnaden är formad för att ge barn och ungdomar utrymme att bearbeta och utforska komplexa frågor. En plats där det är möjligt att ta både trevande och våghalsiga steg utan att bli betraktad utifrån. Rummen är organiserade kring ett atrium där verksamheterna har visuell kontakt med varandra, från utsidan är endast kommunikationsytorna synliga. Passagerna, som bär på en historia av både snabb och långsam förflyttning, upphäver tiden och låter besökarna gå in i sin egen värld. Det långsmala atriet ger ljus åt olika rum. Där inne växer låga ormbunkar och det går endast att nå från insidan. Närmast entrén ligger en yta fylld med vatten. Vattenspegeln är synlig från alla tre våningsplan där det nedre planet befinner sig under ytan. Stilla och i rörelse bryter den ljuset på olika sätt.
BEYOND THE WATER The building is designed to give children space to process complex issues. A place formed to encourage new ways of expression, a possibility to explore without being seen from the outside. The rooms are organized around an atrium where studios have visual contact with each other, from the outside only the area for communication is visible. The passages carry a history of both fast and slow movement, where time cease to exist, and let the visitors enter their own world. The long, narrow atrium brings light into different rooms and can be reached from the inside. Near the entrance is an area filled with water. The water mirror is visible from all three floors where the bottom floor exists below the surface. Still and in motion the light breaks in different ways.

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Axelsson, Sofia, and Anna Vardiero. "Den mjuka sidan av anställningsbarhet." Thesis, Stockholms universitet, Institutionen för pedagogik och didaktik, 2012. http://urn.kb.se/resolve?urn=urn:nbn:se:su:diva-77152.

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Anställningsbarhet är ett begrepp som blommat upp under slutet på 1900-talet. Att varaanställningsbar innebär att ha förmågan att få, behålla och vid behov skaffa sig ett nytt arbete.Det finns två faktorer som påverkar en individs anställningsbarhet, formell kompetens ochinformell kompetens. Vi har intervjuat sex rekryterare i Stockholms län med syftet att belysaderas syn på hur informell kompetens påverkar anställningsbarhet. Vi har ställt öppna frågorsom bland annat syftat till att ta reda på vad som gör en individ anställningsbar när den formellakompetensen är uppfylld samt hur viktigt informell kompetens är i förhållande till formellkompetens. Resultatet av undersökningen visar att det enligt de intervjuade rekryterarna framförallt finns tre typer av informell kompetens: (1) social kompetens, (2) inställning till arbetet och(3) personlighet. Resultatet visar även att informell kompetens i många fall är viktigare änformell kompetens. Vi har också identifierat två olika tekniker för att, i en anställningsintervju,bedöma den arbetssökandes informella kompetens, den reflekterande och den intutiva.

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30

Tisdall, Laurence. "Acclimatization of micropropagated 'Silvan' blackberry." Thesis, McGill University, 1990. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=59835.

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Tissue-cultured shoots and plantlets usually have leaves with non-functional, open stomata and little epicuticular and cuticular wax, resulting in excess evapotranspiration after transplantation. Various strategies were evaluated to decrease ex vitro acclimatization difficulties for 'Silvan' blackberry, including transplanting unrooted shoots, increasing the medium agar concentration from 6 to 9 or 12 g/l and diluting the basal medium. Increased medium agar concentrations and medium dilution did not improve survival or growth. Stomatal function resumed sooner in new leaves of plantlets than shoots. High relative humidity ($>$95%) and low light intensity (90 $ mu$mol s$ sp{-1}$ m$ sp{-2}$) negatively affected stomatal closure both on acclimatizing transplants and greenhouse-grown plants. Guard cells developed on leaves in vitro were physiologically active but had apparent anatomical abnormalities that inhibited closure. A rapid clearing and staining method was developed for examination of foliar morphology using intact in vitro blackberry (Rubus sp. 'Silvan') and strawberry (Fragaria x ananassa Duch. 'Totem') plantlets and sections of greenhouse-grown 'Silvan' and 'Totem' leaves. This method involved three steps: (1) removing the chlorophyll by autoclaving in 80% ethanol; (2) dissolution of the protoplasm using 5% NaOH at 80$ sp circ$C; (3) post-alkali treatment with 75% bleach (4.5% NaClO) at room temperature for tissue-cultured plantlets and at 55$ sp circ$C for greenhouse-grown leaves. Aqueous safranin (10 mg/l) was used for staining.

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31

Bengtsson, Magnus. "Silane Crosslinked Wood-Thermoplastic Composites." Doctoral thesis, Norwegian University of Science and Technology, Faculty of Engineering Science and Technology, 2005. http://urn.kb.se/resolve?urn=urn:nbn:no:ntnu:diva-680.

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Wood-thermoplastic composites are a more environmental friendly alternative for pressure-treated lumber but can also replace engineering plastic products. These composites have been on the market for more than ten years now and have mainly been used in building and automotive applications. The use of these materials has shown that long-term properties, durability, and toughness are the main problems. The aim of this study was to investigate if silane crosslinking could be one way of solving these problems. Silane crosslinked woodthermoplastic composites with polyethylene as the matrix and wood flour as reinforcement were manufactured by melt compounding. A reactive extrusion process was developed where compounding of polyethylene and wood flour and silane grafting were carried out simultaneously. The extrusion process was optimized and used in larger scale profiling of crosslinked composites. The composite materials were evaluated using chemical analysis, mechanical testing, spectroscopic analysis, thermal analysis, and electron microscopy. The crosslinking reaction was shown to be initiated during compounding of the composites and was significantly increased upon storage in a high humidity sauna at elevated temperature. The crosslinked composites showed toughness, impact strength and creep properties superior to the non-crosslinked composites. Scanning electron microscopy on the fracture surface of the crosslinked composites revealed good interfacial adhesion between the wood fibres and the polyethylene matrix. Based on results from this study, it is proposed that silane crosslinking creates a three dimensional network in the polyethylene matrix with chemical bonding to the wood fibres.

Future evaluation of results from accelerated weathering studies will reveal if silane crosslinking can improve the durability of wood-thermoplastic composites during outdoor exposure. Investigation of the potential of silane crosslinking on other type of composite systems with other thermoplastic matrices and natural fibres would also be of interest.

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Mohammed, Tan I. "Properties of silane-crosslinked HDPE." Thesis, University of Leeds, 1988. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.234047.

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Iso-Junno, T. (Tarmo). "Jännevirran sillan väsymismitoitus mitatulla liikennekuormalla." Master's thesis, University of Oulu, 2017. http://urn.fi/URN:NBN:fi:oulu-201704131498.

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Työssä verrataan Eurokoodin mukaisia väsytyskuormakaavioita Suomessa mitattuihin todellisiin liikennekuormiin. Eurokoodin mukainen väsymismitoitus tehdään väsytyskuormakaavioille FLM 3 ja FLM 4. Mitatut liikennekuormat on saatu Suomessa tehdyistä liikenteen automaattisista mittauksista, akselimassatutkimuksesta ja silta-WIM -mittauksista. Väsymismitoitus tehdään Jännevirran sillalle. Silta on teräksinen jatkuva betonikantinen liittopalkkisilta, jonka jännemitat ovat 50 + 70 + 100 + 120 + 100 + 70 + 50 m ja hyödyllinen leveys on 15,25 m. Tutkittavat detaljityypit ovat: laipan jatkaminen, lisälevyn päättäminen, vaarnan hitsi laippaan ja pystyjäykisteen hitsi alalaippaan. Tavoitteena on selvittää, miten tarkasti eri liikennekuormilla tehdyt mitoitukset vastaavat toisiaan ja onko FLM 3 mahdollisesti yli- tai alimitoittava todelliseen liikennekuormaan verrattuna tutkittavassa pitkiä jännevälejä sisältävässä sillassa. Mitatusta liikennekuormasta arvioidaan myös ajoneuvojen painorajoitusten noston vaikutusta liikenteen väsytyskuormittavuuteen. Lisäksi työssä perehdytään hitsin jälkikäsittelymenetelmiin, joilla voi parantaa detaljien väsymiskestävyyttä. Laskennan tuloksissa sillan kahdessa lyhyimmässä aukossa (L = 50 m ja 70 m) sijaitsevien detaljien väsymismitoituksessa FLM 3 on ylimitoittava. Kahden pisimmän aukon (L =100 m ja 120 m) kriittisissä detaljeissa FLM 3 on alimitoittava. Detaljien väsymisvauriot pysyvät kuitenkin sallituissa rajoissa. Jänneväliltään pitkissä aukoissa mitattujen liikennekuormien aiheuttama väsymisvaurio on suuri, koska pitkälle jännevälille mahtuu kulkemaan monta raskasta ajoneuvoa peräkkäin. FLM 4 mitoituksen tulokset ovat epäluotettavia muihin väsytyskuormiin verrattuna. Tutkimuksen tulosten perusteella FLM 3 mitoitus vaatii kehittämistä, jotta se soveltuu käytettäväksi Suomessa jänneväliltään pitkille silloille. Myös FLM 4 mitoitus pitäisi kehittää Suomen ajoneuvoliikennettä vastaavaksi
In this work Eurocode Fatigue Load Models are compared with real traffic loads measured in Finland. The fatigue design conforming to Eurocode is done with FLM 3 and FLM 4. The measured traffic loads have been obtained from automatic traffic measurements, axle load survey and bridge weigh in motion measurements that have been carried out in Finland. The fatigue design is done to the Jännevirta Bridge. The bridge is a continuous composite girder bridge, which spans are 50 + 70 + 100 + 120 + 100 + 70 + 50 m and the effective width is 15.25 m. The details chosen for the research are: the splice of the flange, the additional plate closure, the shear stud welded to the flange and the vertical stiffener welded to the lower flange. The aim is to find out how closely the fatigue design done by different traffic loads correspond to each other and whether the FLM 3 is over- or underestimating fatigue damage compared with the actual traffic load in the bridge with long spans. The change in fatigue damage due to increased vehicle weight limits is examined based on measured traffic loads. In addition, the post weld treatment methods that can improve the fatigue strength of the details are studied in the work. The calculation results show that the FLM 3 is overestimating fatigue damage in the details located at the two shortest opening of the bridge (L = 50 m and 70 m). In critical details located at the two longest opening of the bridge (L = 100 m and 120 m) the FLM 3 is underestimating fatigue damage. However, the fatigue damage of all details remains within the permitted limits. The fatigue damage is high in the long spans because many heavy vehicles in a row fit onto the long span. The FLM 4 results are unreliable in comparison with other fatigue loading. Based on the results FLM 3 requires the development so that it is suitable for use in Finland for long span bridges. Also FLM 4 should be developed to match the Finnish vehicle traffic

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Blážová, Hana. "Finanční analýza společnosti Silon, a.s." Master's thesis, Vysoká škola ekonomická v Praze, 2006. http://www.nusl.cz/ntk/nusl-328.

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Práce hodnotí hospodaření společnosti Silon,a.s. v letech 2000 až 2004. V teoretické části práce jsou popsány metody finanční analýzy, které jsou použity v praktické části samotného hodnocení společnosti. V praktické části se seznámíme se společností samotnou, dále pak s odvětvím, v kterém podniká, analýzou abslutních ukazatelů, analýzou rozdílových ukazatelů a analýzou poměrových ukazatelů. V práci jsou dále spočteny bonitní a bankrotní modely pro společnost Silon,a.s., systém ukazatelů Du Pont a ekonomická přidaná hodnota.

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Cordes, Martin. "Intramolekulare Cyclisierungen chiraler, "c-zentrierter" Propargylsilane und enantioselektive Synthesen anellierter Azeptine zum Aufabu des BD-Grundgerüstes von Cephalotaxin." [S.l. : s.n.], 2005. http://deposit.ddb.de/cgi-bin/dokserv?idn=975446096.

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Santos, Marcia Cristina Gonçalves dos. "Estudo de filmes polimericos contendo silanos y-UPS e VS como revestimentos promotores de adesão em superficies galvanizadas e eletrodepositos de ligas ZN/FE e ZN/Co." [s.n.], 2005. http://repositorio.unicamp.br/jspui/handle/REPOSIP/263596.

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Orientador: Celia Marina de Alvarenga Freire
Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Engenharia mecanica
Made available in DSpace on 2018-08-04T09:48:54Z (GMT). No. of bitstreams: 1 Santos_MarciaCristinaGoncalvesdos_M.pdf: 7174846 bytes, checksum: 71b57284d8926f02702b824e265c956a (MD5) Previous issue date: 2005
Resumo: A excelente resistência do Zinco em diferentes ambientes corrosivos e sua habilidade em proteger o aço, fazem do aço galvanizado e eletrodepósitos, materiais comuns na indústria automotiva e de construção civil. Os substratos de aço galvanizado e eletrodepósitos de Zinco necessitam, no entanto, ser protegidos em ambientes altamente corrosivos por revestimentos orgânicos (pinturas).A má aderência do sistema Zinco/pintura faz com que a superfície do substrato de Zinco receba um pré-tratamento contendo Cromo relativamente barato e efetivo porém, tóxico ao homem e ao meio ambiente. Filmes poliméricos contendo silanos organofuncionais surgem como alternativa à substituição de pré-tratamento livre de Cromo hexavalente 'CR POT. +6¿, pois são moléculas que podem atuar como agente de acoplamento, promotores de adesão e como protetoras de superfície. A principal vantagem da sua utilização é a promoção da adesão entre materiais orgânicos (pinturas) e inorgânicos (metais). Os sistemas Galvanizado/Silano e Ligas eletrodepositadas/Silano, foram estudados nesta dissertação. Para tanto, técnicas como EIE (Espectroscopia de Impedância Eletroquímica), XPS (Espectrometria Fotoelétrica de Emissão de Raios-X), Ângulo de Contato e análises microscópicas foram utilizadas. A avaliação da resistência por barreira foi feita através da Espectroscopia de Impedância Eletroquímica em solução de 0,1 M de NaCI, comparando-se os desempenhos dos revestimentos. A cura induziu uma modificação importante nos diagramas de impedância, além de outras variáveis, como a concentração, o tempo de hidrólise, os tipos de silano e os substratos diferentes. Os resultados indicaram o Zn/Co revestido por VS e Zn/Fe revestido por 'gama¿-UPS como os sistemas mais promissores
Abstract: The Zinc' s excellent resistance, as used in differents corrosive environments, and its hability to protect steel, make galvanized steel (HDG) and Zinc electrodepositions very usual materiaIs in the automotive and construction industries. Galvanized steel and Zinc electrodepositions substrates need, however, to be protected from strongly corrosive environments by organic coatings (painting). Zinc/paint system weak adhesion results in a relatively cheap and effective zinc substrate pretreatment, however toxic to humam being, and also to the environment. Organofunctional silanes appear as an altemative to substitute this pretreatment, without making use of hexavalent chromium 'CR POT. +6¿), because they are bifuncional molecules that can act as adhesion promoters and surface protectors. The main benefit to employ them is to promote adhesion between organic (painting) and inorganic (metals) materiaIs. The GalvanizedlSilane and Electrodeposition Alloys/Silane systems had been studied in this essay. Techniques like EIS (Electrochemical Impedance Spectroscopy), XPS (X-Ray Emission Photoeletric Spectrometry), Contact Angle and microscopical analyses were used in this work. The barrier for resistance was evaluated through Electrochemical Impedance Spectroscopy in a 0,1M NaCI solution comparing coatings performances. Curing caused as importante modification in the impedance diagrams, as well as other variables like concentration, hydrolysis time, silane types and different substrates. The results indicate the Zn/Co alloy coated for VS and Zn/Fe alloy coated for 'gama¿-UPS as the systems most promising
Mestrado
Materiais e Processos de Fabricação
Mestre em Engenharia Mecânica

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37

Santos, Marcia Cristina Gonçalves dos. "Avaliação do desempenho de filmes contendo silanos e sais de terras raras para proteção contra corrosão de camadas de ZnFe eletrodepositadas." [s.n.], 2009. http://repositorio.unicamp.br/jspui/handle/REPOSIP/263579.

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Orientador: Celia Marina de Alvarenga Freire
Tese (doutorado) - Universidade Estadual de Campinas, Faculdade de Engenharia Mecanica
Made available in DSpace on 2018-08-13T07:27:48Z (GMT). No. of bitstreams: 1 Santos_MarciaCristinaGoncalvesdos_D.pdf: 5280662 bytes, checksum: 763649a5f0d49aa48853a896ab0335c2 (MD5) Previous issue date: 2009
Resumo: Aço galvanizado e aço eletrodepositado com liga ZnFe são materiais comuns na indústria de construção civil e automotiva. Esses materiais à base de zinco necessitam, entretanto, serem protegidos de ambientes corrosivos através de um tratamento de superfície que geralmente contém cromo hexavalente ( Cr6+), tóxico para o meio ambiente e cancerígeno para o homem. O presente trabalho apresenta um estudo com filmes contendo diferentes silanos: viniltrietoxissilano (VS), bis-(1,2-[trietoxissilil] etano) (BTSE) ou bis-(3-[trietoxissilil]-propil? tetrassulfeto (BTESPTS) e nitratos de terras raras (Ce ou La), como revestimentos de conversão para a camada de liga ZnFe. Esses sistemas foram avaliados através das análises de Espectroscopia Fotoelétrica de Emissão de Raios-X (XPS), das Curvas de Polarização, da Espectroscopia de Impedância Eletroquímica (EIE), da Microscopia Eletrônica de Varredura (MEV) e Espectrometria de Energia Dispersiva (EDS). Os resultados de EIE e polarização indicaram que os sistemas estudados foram eficientes contra corrosão e que seu desempenho dependia do tipo de silano. Os sistemas ZnFe+Ce+BTSE+BTESPTS e ZnFe+La+BTSE+BTESPTS mostraram o melhor resultado contra corrosão.
Abstract: Galvanized and zinc electroplated steels are very useful materials in automotive and construction industries. These zinc based materials, however, need to be protected against corrosive environments through a surface treatment that generally has hexavalent chromium wich is toxic to the environment and may cause cancer to human being. This thesis shows a study about films containing different silanes: vinyltriethoxysilane (VS), bis-(1,2-[triethoxysilyl]ethane) (BTSE) or is-(3-[triethoxysilyl]-propyl]tetrasulfide (BTESPTS) and rare earth nitrates (Ce, La) as conversion coatings to the zinc-iron alloy electroplated steel. These systems were evaluated using X-Ray Photoelectron Spectroscopy (XPS), Polarization Curves, Electrochemical Impedance Spectroscopy (EIS), Scanning Electron Microscopy (SEM) and EDS. The EIS and Polarization results have shown that the systems under study were efficient against corrosion and its performance depended upon the type of silane. The inciron+Ce+BTSE+ BTESPT and zinc-iron+La+BTSE+BTESPT systems have shown the best result against corrosion.
Doutorado
Materiais e Processos de Fabricação
Doutor em Engenharia Mecânica

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38

Silén, Teija. "Somatosensory and motor cortical activity in patients and carriers of Unverricht-Lundborg type progressive myoclonus epilepsy." Helsinki : University of Helsinki, 2003. http://ethesis.helsinki.fi/julkaisut/laa/kliin/vk/silen/.

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Tidrick, Shari Lynne. "Investigations of the silane/epoxy matrix interphase for silane coupling agent blends of varying composition." Case Western Reserve University School of Graduate Studies / OhioLINK, 1991. http://rave.ohiolink.edu/etdc/view?acc_num=case1055857671.

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40

Kotík, Libor. "Konstrukce sila na cukr." Master's thesis, Vysoké učení technické v Brně. Fakulta stavební, 2015. http://www.nusl.cz/ntk/nusl-227611.

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The matter of this thesis is static design and examination of prestressed storage tank to 50000 tons of sugar. Computational model of the steel roof structure is processed and its effect on the silos. Loads is provided of sugar. Optimal design is performed and assessment ultimate and serviceability limit state reinforced concrete and prestressing horizontal silo wall including local load. Next, it is performed the design of a reinforced concrete of the plane bed and column and assessment at the ultimate limit state. The thesis is also drawing documentation, technical report and visualization of construction process. The aim of this work is to the design of the main components based on the required storage capacity tank, mechanical properties of the stored material and technical amenities.

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Fučík, Petr. "Vyhrnovací dopravník kalového sila." Master's thesis, Vysoké učení technické v Brně. Fakulta strojního inženýrství, 2008. http://www.nusl.cz/ntk/nusl-228000.

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The subject of this diploma thesis is engineering design of the sediment conveyer. Conveyer is instrumental to total emptying of sediment silo that is situated in a sewage treatment plant. Proposed construction has to fulfill the specified functional requirements and parameters. Parts of solution are also necessary analytical and FEM calculations.

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Jönsson, Johan. "”Andra sidan” : Stadsplaneringshistoria i efterkrigstidens Laholm." Thesis, Högskolan i Halmstad, Sektionen för lärarutbildning (LUT), 2010. http://urn.kb.se/resolve?urn=urn:nbn:se:hh:diva-15075.

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Denna uppsats behandlar den debatt som funnits i efterkrigstidens Laholm kring att bebygga Köpingelandet eller ej. Laholm är bebyggt på Lagans sydsida, nordsidan är fri från bebyggelse. Det finns de som anser att nordsidan bör bebyggas och de som anser att den bör hållas fri från sådan. Syftet är att följa debatten genom aktörerna i frågan samt deras argument och motiv. Det material som undersökts är kommunprotokoll, skrivelser samt översiktsplaner. Även tidningar och Internet har använts. I analysdelen har Sverker Oredssons argumentationsteori använts. En slutsats är att frågan delar folk. Det finns flera argument som stödjer respektive ståndpunkt.

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Wallinder, Jonas. "Vesper : möbler vid sidan av tiden." Thesis, Konstfack, Inredningsarkitektur & Möbeldesign, 2009. http://urn.kb.se/resolve?urn=urn:nbn:se:konstfack:diva-2724.

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I den här rapporten redogörs för processen vid framtagandet av det första objektet i möbelserien Vesper. Författarens tillika formgivarens tankar kring olika materials narrativa förmåga i relation till en betraktares förförståelse, föranleder en formgivningsprocess som resulterar i ett arbetsbord där material och symbolspråk tänks förmedla sköna värden. Uttryck av varaktighet och omsorg i en kontext med tillfällighetssyndrom.
Kandidatexamen 2009

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Gustrin, Linda. "Den mörka sidan av turismen, barnsexturism." Thesis, Karlstad University, Faculty of Social and Life Sciences, 2010. http://urn.kb.se/resolve?urn=urn:nbn:se:kau:diva-5788.

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SAMMANFATTNING

Turismen är den största folkvandringen i modern tid. Under år 2008 reste 922 miljoner turister, denna siffra beräknas stiga till 1,6 miljarder år 2020. I många år har turismindustrin blivit utmanad av media och myndigheter att ge ett snabbt socialt ansvar, till följd av öppna gränser och arbetskraftens migration. Två speciellt besvärliga fenomen är, människohandel och barnsexturism. Denna problematik är vanlig i Thailand, ett land med rykte om att vara en sexdestination.

Thailand är idag en stor turistdestination med ungefär 14 500 000 miljoner turister varje år. Många svenskar reser till Thailand för; sol, bad och affärer. Under perioden år 1965-1975, präglades många människors liv av Vietnamkriget. Många soldaters rekreationsresor förlades till Thailand. Barnsexturismen växte upp som en organiserad handel med barer och bordeller, inrett speciellt för soldaterna. Efter kriget växte en ny infrastruktur upp, sexturism. Thailand blev känt för att vara en internationell barnsexturism destination.

Hur många barn som är utsatta av sexindustrin är svårt att avgöra, då ingen vet. En del påstår att summan av alla barn omfattar över 3 miljoner. Dessa uppgifter kommer från Frankrike år 2005. På grund av ökad globalisering av ekonomi, media och tillströmning av konsumentvaror har den thailändska materialismen och konsumtionen ökat blad de thailändska familjerna. Detta har bidragit till att befolkningen har sett möjligheter att se familjens döttrar som en snabb och bekväm metod till att tjäna pengar och för att kunna få möjligheten att köpa konsumentvaror. Turismindustrin kan också utnyttja de traditionella etniska livsstilar som lokalbefolkningen kan inneha. Ett resultat av detta innebär att kvinnor kan uppleva sig själva som en kulturell handelsvara, samt en del av markandsföringen och av den turistprodukt de blir. Barnen vänder sig till prostitution för rädsla av fattigdom.

Barnsexturism förekommer både i industrialiserade länder samt utvecklingsländer, det är ett globalt problem. Ju mer vi reser, ju bredare och djupare blir problemet och det slutar inte att växa. En organisation som arbetar med att motverka barnsexturism är, ECPAT – End Child Prostitution, Child Pornography and Trafficking in Children for Sexual Purposes. Från att varit en liten organisation har verksamheten växt och utvecklats. Nu finns den representerad i 122 länder, Sverige är ett utav dessa länder. Sveriges stora researrangörer samarbetar med organisationen. Researrangörerna har skrivit på uppförandekoderna. Detta är ett sätt att arbeta för att motverka barnsexturism på destinationerna och hemma i Sverige.

Uppsatsens teori utgår från problematiken bakom barnsexturismens ursprung, för att sedan följa utvecklingen fram i tiden. Författaren önskar ta reda på om resenärer har kännedom av vad organisationen ECPAT arbetar med. Om resenärerna har vetskap om researrangörers samarbete med ECPAT. Hur arbetar researrangörerna för att motverka barnsexturism? Resultatet av studien visar att Sveriges stora researrangörer Fritidsresor och Ving samarbetar med ECPAT för att motverka barnsexturism och att information, kommunikation och utbildning är tre steg för att förebygga problemet. Det finns tydliga tendenser på att resenärers kännedom om ECPAT är bristande och detta bör förebyggas genom att Sveriges regering tar sitt ansvar och för vidare frågan för debatt i media. Studien har utgått från en induktiv ansats där författaren har genomfört både kvalitativa undersökningar samt kvantitativa, dessa i form av litteraturfördjupning, intervjuer och en enkätundersökning. Trevlig läsning!

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De, Waterbeemd Marion Van. "Silane Condensation to nanoparticles in suspension." Thesis, University of Kent, 2009. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.516211.

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Smith, David Murray. "Diode laser spectroscopy of silane plasmas." Thesis, University of Cambridge, 1992. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.259622.

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47

Fall, Yagamare. "Application des réactions de Sila Hofmann et de Sila Cope à la synthèse de phéromones." Grenoble 2 : ANRT, 1986. http://catalogue.bnf.fr/ark:/12148/cb37597502t.

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Fall, Yagamare. "Application des réactions de Sila Hofmann et de Sila Cope à la synthèse de phéromones." Paris 11, 1986. http://www.theses.fr/1986PA112146.

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Une nouvelle méthode de substitution des amines allyliques par les organométalliques a été utilisée. Une étude de l'action de diverses espèces organométalliques sur des sels d'ammonium quaternaires et des chlorures allyliques de configuration Z a montré la sélectivité des réactifs de Grignard dans ces réactions. Enfin, l'utilisation de réactions de fragmentations induites par le silicium a permis de réaliser la synthèse de phéromones diéniques 1,5 à partir de tétrahydropyridines, montrant ainsi la généralité de cette approche
Allylic tertiary amines were substituted with Grignard reagents after activation with alkyl chloroformates. Action of various organometallic species upon allylic chlorides and ammonium salts of Z configuration was studied. The results showed that the best selectivity is obtained with Grignard reagents. Finally use of silicon induced fragmentations led to the synthesis of 1,5 dienic pheromones from tetrahydropyridines as starting material, demonstrating the generality of this approach

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Katipoglu, Ceren. "An Analysis Of Architect Sinan&#039." Master's thesis, METU, 2007. http://etd.lib.metu.edu.tr/upload/3/12608641/index.pdf.

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This thesis focuses on the late period mosques of architect Sinan in terms of their structural systems, the relation with their environment, and the identities of their patrons. The links amongst the role of the patron, his or her status in the state, materials used in the mosques, location choice and the spatial distribution of the mosques are researched on the bases of these six late period mosques of Sinan. In this perspective, the social background of the Ottoman Empire in the sixteenth century is the first focal point of the thesis. The relations between the decadence of the institutions, the political conditions of the Ottoman Empire and the architectural production during the last quarter of the sixteenth century are examined in the second chapter of this thesis. In the third chapter these six late period mosques as the sampling case are described in detail and evaluated in terms of their bearing systems, construction materials, the site features and the relation with their patrons. Though, being one of the favorite subjects in the Ottoman architectural history, there are many research and interpretations on Sinan&
#8217
s architectural style, works on late period mosques are limited and not specifically focused. In the fourth chapter of the study these limited interpretations are brought together and evaluated in the light of the background information supplied in the previous chapter of the thesis. In this framework, the aim of this study is not only to assess the late period works of Sinan as a tool to trace his architectural process, but also to unveil the relations with the identities of the patrons and locational and structural features of the mosques.

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Hanetho, Sidsel Meli. "Hybrid Aminopropyl Silane-based Coatings on Steel." Doctoral thesis, Norges teknisk-naturvitenskapelige universitet, Institutt for materialteknologi, 2012. http://urn.kb.se/resolve?urn=urn:nbn:no:ntnu:diva-19540.

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Thin coatings applied to metals is a material-saving process to improve the surface properties such as abrasion and corrosion resistance of the substrate. Pure inorganic coatings are generally too thin to offer long-term protection, and thick coatings are prone to crack formation during processing. However, by incorporating an organic moiety, thicker and more flexible coatings can be developed. Hence sols and coatings based on 3-(aminopropyl)triethoxysilane, γ-APS, have been synthesized as part of the PhD work. Initially, pure inorganic alkoxide-based silica coatings were fabricated. These coatings displayed poor abrasion resistance and were poor alternatives with respect to corrosion protection of carbon steel. The need for thicker coatings was thus proposed, and hybrid inorganic-organic coatings were suggested as a probable solution. Thus in Paper I, hybrid inorganicorganic γ-APS-based sols were synthesized and characterized. Molar ratios of water (or solvent) and silane ratios and sol hydrolysis pH were varied. 29Si NMR was used to study the hydrolysis and condensation reactions. The kinetic mechanisms of the hydrolysis and condensation of the sols showed a difference in the structures formed depending on the water/silane ratio and the sol pH. Increasing the water/silane ratio promoted a faster condensation reaction as evidenced by the early evolution of more condensed species. Reducing the sol pH enabled the condensation reaction to slow down thus fascilitating a more complete hydrolysis reaction. Furthermore, hypostoichiometric sols were shown to consist of linear structures while stoichiometric and hyperstoichiometric sols were more cross-linked as evidenced by the higher viscosity and the combination of T2 and T3 species detected by 29Si NMR. In Paper II, coatings were fabricated from the sols described in Paper I. Transparent and homogeneous hybrid aminopropyl silane-based coatings on steel were prepared by the sol-gel method using the hydrolyzed γ-APS sols as precursors. The coatings were fabricated by dip coating, and the effect of pH, water/silane ratio and solvent/silane ratio during the coating process was investigated with respect to thermal stability, coating thickness, roughness, porosity, contact angle and abrasion resistance. The thickness of the coatings varied between 0.17 and 4.1 μm and was controlled by the preparation conditions of the sol as well as the viscosity of the sols. The coatings were in general smooth and the roughness in the order of a few nanometers. The contact angles with water of the coatings varied from 60 to 80° Organic pentadecane was shown to wet the coatings, which suggested that the coatings also displayed hydrophobic properties. The abrasion resistance improved with decreasing pH of the water used during hydrolysis of the silane. The coatings were characterized with respect to delamination and smearing. Thicker coatings were delaminated while thinner coatings were smeared and displayed lubricating properties. Gels of the hybrid aminopropyl silane-based sols were thermally stable up to 350°C, and the gels displayed a low pore volume and a low surface area. In Paper III, hybrid aminopropyl silane-based sols with a variation in the molar ratios of water and silane, the molar ratios of solvent and silane and pH, were applied as a bond coat to carbon steel substrates. Fracture strength, abrasion resistance and electrochemical polarization studies have been conducted on these bond coats. Furthermore, the bond coats were applied a top coat consisting of a polyaspartic paint, and the combination coatings were subsequently exposed to an ageing resistance test for 5 weeks. The bond coat-top coat combination coatings were demonstrated to significantly improve the corrosion protection behavior of carbon steel. The thickness of the bond coats varied from 0.35 to 4.1 μm, while the bond coat-top coat combination coatings were all in the range of 100 μm.

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Dissertations / Theses on the topic 'Silan'

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