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Topographical influence on soil chemistry /Sørensen, Rasmus, January 2006 (has links) (PDF)
Licentiatavhandling (sammanfattning) Uppsala : Sveriges lantbruksuniversitet. / Härtill 3 uppsatser.
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Matrix algebra for quantum chemistry /Rubensson, Emanuel H., January 2008 (has links)
Diss. (sammanfattning) Stockholm : Kungliga Tekniska högskolan, 2008. / Härtill 7 uppsatser.
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Click chemistry for the preparation of advanced macromolecular architecturesAkeroyd, Niels 03 1900 (has links)
Thesis (PhD (Chemistry and Polymer Science))--University of Stellenbosch, 2010. / ENGLISH ABSTRACT:
Different click chemistry methods have been used together with Reversible Addition-
Fragmentation chain Transfer (RAFT) mediated polymerization to synthesize macromolecular
architectures.
A new leaving group for RAFT was introduced. This triazole leaving group allows for easy
conjugation of the RAFT agent to various substrates via the copperI catalyzed Huisgen 1,3-dipolar
cycloaddition reaction. Subsequently monomer can be polymerized onto the substrate using the RAFT
agent. This connects the polymer to the substrate via a hydrolytically stable 1,2,3-triazole.
The Mitsunobu reaction was used to chain-end functionalize polymers. The Mitsunobu
reaction allows for the substitution of primary and secondary alcohols with a nucleophile. The
modification of polymer chain-ends was done in two ways. Firstly, thiol-functional chain-ends were
used as the nucleophile in the Mitsunobu reaction using propargyl alcohol as the alcohol. This yielded
alkyne-functional polymers. Thiol chain-end functional polymers were obtained by the aminolysis of
polymers synthesized via RAFT. Secondly, alcohol-functional polymers were modified. In the case of
poly(vinylpyrrolidone), the RAFT group was hydrolyzed and alcohols were obtained. Hydroxyl
functional PEG was obtained commercially. The hydroxyl functionality was reacted in the Mitsunobu
reaction using hydrazoic acid (HN3) as the nucleophile. Azide chain end functional polymers were
obtained. These alkyne and azide chain end functional polymers were subsequently used in the
copperI catalyzed Huisgen 1,3-dipolar cycloaddition reaction.
Ultra Fast Hetero Diels-Alder click chemistry (UFHDA) was used to synthesizes norbornenelike
structures (substituted 2-thiabicyclo[2.2.1]hept-5-ene moieties). Norbornene-like structures can be
polymerized via Ring Opening Metathesis Polymerization (ROMP). Monomers were synthesized
using phenethyl(diethoxyphosphoryl)dithioformate and cyclopentadiene. Macromonomers were
obtained from the UFHDA of Polystyrene (PSTY) synthesized via RAFT, using
phenethyl(diethoxyphosphoryl) dithioformate as the RAFT agent, and cyclopentadiene or
cyclopentadienyl-terminated PEG as the dienes. The obtained (macro) monomers were homo- and copolymerized
using Ring Opening Metathesis Polymerization (ROMP). For the ROMP, four different
Grubbs type catalysts were tested.The ring-strain promoted Huisgen 1,3-dipolar cycloaddition reaction uses cyclooctynes as the
alkyne. The ring-strain in this molecule allows for a fast reaction at room temperature. This reaction is
potentially very interesting for biological applications because it doesn’t require the toxic copper
catalyst. In this work three routes towards cyclooctynes are investigated. PEG was chain end
functionalized with the obtained cyclooctyne derivatives.
Overall, click chemistry methodologies were applied to synthesize different macromolecular
architectures. Results include a new type of RAFT agent that allows for easy conjugation to substrates,
reaction methods for chain end modification of polymers, and the synthesis of new monomers and
polymers. / AFRIKAANSE OPSOMMING:
Verskillende kliek chemie metodes, tesame met Omkeerbare Addisie Fragmentasie ketting
Oordrag beheerde polimerisasie (OAFO), is gebruik vir die sintese van makromolekulêre argitekture.
ʼn Nuwe verlatende groep vir OAFO was bekend gestel. Die triazool verlatende groep bied
die moontlikheid vir gemaklike koppeling van die OAFO agente met ‘n verskeidenheid van substrate
via die koperI gekataliseerde Huisgen 1,3-dipolêre siklo-addisie reaksie. Gevolglik kan monomere
gepolimeriseer word op die substraat deur middel van die OAFO agent. Dit laat toe vir die koppeling
van die polimeer op die substraat via a hidrolitiese stabiele 1,2,3-triazool.
Die Mitsunobu reaksie was gebruik vir die funksionaliseering van die end groepe van die
polimeer ketting. Die Mitsunobu reaksie laat toe vir die substitusie van primêre en sekondêre alkohole
met ‘n nukleofiel. Die verandering van die polimeer ketting end groepe was uitgevoer op twee
verskillende maniere. Eerstens is ketting end groepe met ‘n tiol funktionaliteit gebruik as a nukleofiel
in die Mitsunobu reaksie deur gebruik te maak van propargiel alkohol as die alkohol. Dit het alkyn
funktionele polimere opgelewer. Tiol ketting end funktionele polimere was verkry deur middel van
aminolise van die polimere gesintetiseer via OAFA. Tweedens is alkohol funktionele polimere
gemodifiseer. In die geval van poli(N-vinielpirolidoon) is die OAFA grope gehidroliseer en gevolglik
is alkohole verkry op hierdie manier. Kommersiële funksionele PEG was gebruik. Die hidroksie
funksionele groep was gereageer in die Mitsunobu reaksie deur gebruik te maak van waterstof asied
(HN3) as die nukleofiel. Dit het asied funksionele ketting eindes opgelewer. Die alkyne en asied
ketting end funksionele polimere was gevolglik gebruik in die koperI gekataliseerde Huisgen 1,3-
dipolêre siklo-addisie reaksie.
Ultra Vinnige Hetero Diels-Alder kliek chemie (UVHDA) was gebruik vir die sintese van
norborneen agtige strukture (gesubstitueerde 2-tiabisiklo[2.2.1]hept-5-een groepe). Monomere was
gesintetiseer deur gebruik te maak van fenieletiel(di-etoksifosforiel)di-tioformaat en siklopentadiëen
of siklopentadiëen-getermineerde PEG. Die sintese van makromonomere is verkry via UVHDA deur
gebruik te maak van polistireen, gesintetiseer deur middel van OAFO (waar fenieletiel(dietoksifosforiel)
di-tioformaat gebruik is as OAFO agent), en siklopentadiëen of siklopentadiëengetermineerde PEG. Die makromonomere wat verkry is, is verder gebruik vir homo- en
kopolimerisasie deur middel van Ring Opening Metatesis Polimerisasie, ROMP. Vir die ROMP is vier
verskillende Grubbs tipe kataliste gebruik.
Die ring-spanning bevorderde die Huisgen 1,3,-dipolêre siklo-addissie reaksie waar siklooketyne
gebruik is as die alkyne. Die ring-spanning in die molekule laat toe vir vinninge reaksies by
kamer temperatuur. Die reaksie het die potensiaal vir interessante biologiese toepassings aangesien
dit nie ’n kopper katalis vereis nie wat toksies van aard is. In die studie word drie roetes ten einde to
siko-oktyn ondersoek. PEG was geketting end gefunksionaliseerd met die gevolgde siko-oktyne
afgeleides.
Verskillende kliek chemie metodologiëe was toegepas vir die sintese van verskillende
makromolekulêre argitekture. Resultate sluit in een nuwe tipe OAFO agent wat maklike konjugasie
met substrate bewerkstellig, ketting einde modifikasie van polimere, nuwe monomere en polimere
wat gesintetiseer is.
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The supramolecular chemistry of novel synthetic biomacromolecular assembliesNaidoo, Venthan B. 04 1900 (has links)
Dissertation (PhD)--Stellenbosch University, 2004 / ENGLISH ABSTRACT: Over the past decade peptide bola-amphiphiles have been the subject of much attention
because of their role as potential models of functionalised membranes and as new
generation surfactants. In the quest for new surfactants a peptidomimetic-based approach
was used to design a library of novel 'hybrid' bola-amphiphilic peptide surfactants
derived from sapecin B and a model symmetrical oligo-glycine bola-amphiphile. The
library was divided into different series, each one purpose-built; first, to investigate
hierarchal supramolecular architecture and, second, to investigate potential antimicrobial
activity. The bola-amphiphiles were synthesised using Fmoc-polyamide based solid phase
peptide synthesis and purified via high performance liquid chromatography. The peptide
hybrids were characterised using electro spray mass spectrometry, nuclear magnetic
resonance, different modes of electron microscopy, Fourier-transform infrared
spectroscopy and, in some cases, further studies were done using circular dichroism and
bioactivity tests.
The model bola-amphiphile suberamide(GGh was synthesised using peptide fragment
condensation based on solid phase peptide synthesis. The synthesis is bi-directional
(N~C and C~N) and versatile, making it possible to synthesis new dicarboxylic
oligopeptide bola-amphiphiles and other analogous compounds. The product,
suberarnide(GG)2, was purified using its inherent ability to self-assemble in an acidic
solution.
Novel asymmetrical bola-amphiphiles composed of dipeptide head groups linked via an
aliphatic (I)-amino acid, serving as a hydrocarbon spacer, were also synthesized. Two
small libraries of bola-amphiphiles were established - the first involved variation in
to-amino acid length and the other variation in the C-terminal amino acid. The bolaamphiphiles
were self-assembled in either 0.1% trif1uoroacetic acid or 0.1%
triethylamine. Electron microscopy revealed the formation of a variety of higher order
supramolecular architectures based on ~-sheet self-assembly. FT-IR spectrometry
indicated that interlayer and intralayer hydrogen bond networks, together with strong selfassociation,
promoted by the hydrophobic effect and, in certain instances, electrostatic
interactions, are responsible for the variety of supramolecular architectures. Variations in the higher order structures can be attributed to amino acid composition, specifically
length of m-amino acid, nature of the C-terminal amino acid and the optimised solvent
conditions used for the self-assembly process.
A third library of novel 'hybrid' bola-amphiphilic peptide surfactants, in which a cationic
tripeptide motif from antimicrobial peptides was combined in a hybrid molecule
containing a oi-amino acid residue, was established. These bola-amphiphiles displayed
potent antimicrobial activity against both Gram-positive and Gram-negative bacteria; the
analogues were as active or more active than the leader peptides yet, remarkably,
displayed little or no appreciable haemolytic activity. These organopeptide bolaamphiphiles
thus demonstrated selective toxicity towards bacteria. The hydrophobicity
imparted by the co-amino acid has contrasting effects on haemolysis and antimicrobial
activity of the peptide analogues. The other unique feature of these peptides and their
analogues is the fact they self-assembled into complex supramolecular architectures,
composed primarily of ~-sheets. Their self-assembly is primarily governed by
hydrophobic interactions together with inter and intralayer hydrogen bonding. Electron
microscopy clearly revealed higher order structures for both peptides and analogues. The
generation of higher order supramolecular architecture is dependent on optimisation of ~-
sheet self-assembly whereas antimicrobial activity is dependent on the balance between
net positive charge and optimum hydrophobicity of the peptide hybrids.
This study has demonstrated that it is possible to design hybrid peptide surfactants
capable of producing higher order supramolecular architecture and improving the
antimicrobial activity whilst reducing the haemolytic effect. The study and design of
these versatile 'purpose-built' bio-inspired surfactants heralds a novel approach, one that
shows tremendous potential. / AFRIKAANSE OPSOMMING: Die afgelope dekade het bola-amfifiliese peptiede baie aandag geniet weens hulle rolle as
potensiële modelle van gefunksionaliseerde membrane en as 'n nuwe generasie
surfaktante. In die soeke na nuwe surfaktante is 'n peptiedornimetiese benadering gevolg
om 'n biblioteek van nuwe "hibried" bola-amfifiliese peptiedsurfaktante van sapesien B
en 'n simmetriese oligoglisien bola-amfifil af te lei. Die biblioteek is in verskillende
reekse onderverdeel. Elke reeks is doelmatig vervaardig om ondersoek in te stel na twee
aspekte, nl. die rangorde van die supramolekulêre strukture en die potensiële
antirnikrobiese aktiwiteit. Fmoc-poliamied gebaseerde soliedefase-peptied-sin-tese is
aangewend vir die sintese van die bola-amfifile en hulle is met behulp van hoë
doeltreffendheid vloeistofchromatografie gesuiwer. Die peptiedhibriede is gekarakteriseer
met behulp van elekrosproei massaspektrometrie, kern-magnetiese resonansie,
verskillende modusse elektronrnikroskopie, Fourier-transform infrarooispektrometrie en,
in sommige gevalle is verdere studies met sirkulêre dichroïsme en bioaktiwiteitstoetsing
uitgevoer.
Die bola-amfifilsuberamiedtflfij--model is met behulp van peptiedfragment-konden-sasie
gesintetiseer gegrond op soliedefase-peptiedsintese. Dit sintese vind in twee rigtings plaas
(N~C en C~N) en is veelsydig aangesien dit die sintese van sowel nuwe dikar-boksielbola-
amfifile as ander analoë verbindings moontlik maak. Die produk, suber-arnied(GG)2,
is gesuiwer met behulp van die verbinding se inherente vermoë tot self-montering in suur
oplossings.
Nuwe assimetriese bola-amfifile, saamgestel uit dipeptiedkopgroepe, gekoppel via 'n
alifatiese ro-aminosuur, wat as koolwaterstofspasieerder dien, is ook gesintetiseer. Twee
klein bola-amfifilbiblioteke is saamgestel - die een het variasies in die ro-aminosuur se
lengte omvat en die ander een variasies in die C-terrninale aminosuur. Selfmontering van
die bola-amfifile het plaasgevind in of 0,1 % trifluorasynsuur Of 0,1 % trietielamien.
Elektronrnikroskopie het die bestaan van 'n verskeidenheid hoërorde supramolekulêre
strukture, gegrond op p-plaatselfmontering, aangetoon. Uit FT-IR-spektrometrie blyk dit
dat inter - en intralaag waterstofbinbdingsnetwerke en sterk selfassosiasie, 19. word
bevorder deur die hidrofobiese effek en, in sekere gevalle, elektrostatiese interaksies, is
verantwoordelik vir die verskeidenheid supramolekulêre strukture. Variasies in die hoërorde strukture kan toegeskryf word aan aminosuursamestelling, in besonder die
lengte van die ro-aminosuur, die aard van die C-terminale aminosuur en die geoptimiseerde
oplosmiddelkondisies wat gebruik is vir die selfmonteringsproses.
'n Derde biblioteek nuwe "hibried" bola-amfifiliese peptiedsurfaktante, waarin 'n kationiese
tripeptiedmotief uit antimikrobiale peptiede gekombineer is met 'n m-aminosuurresidu,
is geskep. Sommige van hierdie bola-amfifile het 'n kragtige antimikrobiese
aktiwiteit teenoor sowel Gram-positiewe as Gram-negatiewe bakterieë gertoon. Die
analoë strukture was aktief, of selfs meer aktief as die voorste peptiede maar het,
verbasend genoeg, nie 'n beduidende hemolitiese aktiwiteit vertoon nie. Hierdie
organopeptied bola-amfifil het dus 'n selektiewe toksisiteit teenoor bakterieë vertoon. Die
hidrofo-bisiteit, as gevolg van die ui-aminosuur, het 'n resiproke effek op hemolise en die
antimikrobiese aktiwiteit van die peptiedanaloë. Die ander uitstaande kenmerk van die
peptiede en hulle analoë is die vermoë om te selfmonteer en komplekse supramolekulêre
strukture, bestaande hoofsaaklik uit ~-plate, te vorm. Hierdie selfmontering word in
hoofsaak beheer deur hidrofobiese interaksies asook inter - en intralaagwaterstofbinding.
Elektronmikroskopie het duidelik hoërorde strukture getoon by sowel dié peptiede as
hulle analoë. Die ontwikkeling van hoërorde supramolekulêre struktuurvorms is afhanklik
van die optimalisering van die ~-plaatselfmontering. Daarteenoor is die antimikro-biese
aktiwiteit afhanklik van die balans tussen die netto positiewe lading en die opti-male
hidrofobisiteit van die peptiedhibriede.
Hierdie studie het getoon dat dit moontlik is om hibriedsurfaktante te ontwerp wat
hoërorde supramolekulêre strukture te produseer en om die antimikrobiese aktiwiteit te
verbeter terwyl die hemolitiese effek verminder word. Die studie en ontwerp van hier-die
veeldoelige, "doelmatig-gesintetiseerde" biogeïnspireerde surfakante stel 'n unieke
benadering daar, wat oor groot potensiaal beskik.
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Protein chemistry and mass spectrometry in biochemical researchPompach, Petr January 2006 (has links)
Protein chemistry and mass spectrometry in biochemicul research Petr Pompach Ph. D. Thesis Department of Biochemistry Faculty of Science Charles University Supervisor: Doc. RNDr. Karel Bezouška, CSc. Prague 2006 tEia*iiitg;;tiBiÉ (n OO oO O\ O\ C.l C.l .+ : : : : :ÉGlc.l c.: Ý l.) a z t-r (J Fl E) lra J a U z a Fr tl5 a Fr zr\J) alai P.: ai a - Lr o L d a (|i iť r h t) o() r a a q C) ! - H F (n F íi a o) O a X, o >. C) o .l I +i oL o -O o o l.r U) N z oo - O o I L a Li +i vi ol Ei!t ,ql -l E 3a (n z E F a F z F z U pg ť: šé3; Ei ĚE$áE€EÉEáiz E ÉĚ E Ě s E ; u ; ó =-E5Ě:gd:'i = t Ei giĚg;;:1lV)iĚggĚgEsáEĚi* E Ě=;Éía:š;Éť E É!řěEEEFgg : ií€gáŤÉ5 ž:::š;;i : zi:€ i=ts€ĚiĚišĚÉiš;š5ĚiE.:. = = € .T ŽlĚE g;t$jíigggřEE iuEái E :É€šáĚ g;iÉ{Ě;ítÉÉF€Ě E iĚĚĚi ; š;šš!iiE řě E ši gE ig Ý E giĚE šgig;išiš::gígFĚi+g s E *'suĚšěĚ Ěie *Ěá, uE trE s'' -k*-=a.*:.* g: EPE€'šEEř€9 ěÍ.E ;š e::E;;áe;iÉgřšiE řĚt.E*E$*eE=$[:gř.v :IEF€=áfrE;='2E-ď ?! : g"HEu.:i=ĚE€;ÉE€ř€ Eš,*éEě9t.F;EE.Ě., ťiEEEE*ě:iiEĚgĚ:Éžáx;šš ř 5šEtsť uE.E.= e *n á:; € žEř: € ÉE.: i= ř-g p; i ĚĚ;: € i íEĚ = Hi;2E É*Ě u, Ě y ?' : 6 ě ř ; fij .: .c F=E;-sg&,Ě7Éď€3E€€ -i€E.E =:Í E=bÉ::ň !B:,: E t šáč š 3e = Ě l E ř f L Ei:í:9:*q;€gq3:;:.E: ťšÉI: Ě i ?E Ě ; Éi É.EE E EEE :!rEě45BEE EE.= €Eě íEEra-vĚ=3ň €.E3 iillťlgtššgtgi;g;ggiĚš; iáágá9 $*i;Ě:E; -Eás;t;É$ \o Ěi gi...
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STUDIES IN AZIRIDINE-ALLYLSILANE CHEMISTRY: EXTENSION OF SCOPELapinsky, David J. 20 December 2002 (has links)
No description available.
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Chemistry of dawsonites and application in catalysisStoica, Georgiana 18 February 2010 (has links)
La dawsonita es un mineral cristalino hallado generalmente en la naturaleza en forma de hidróxicarbonato de sodio y aluminio, NaAlCO3(OH)2. Además del mineral, se han sintetizado diferentes tipos de dawsonitas variando su composición, es decir, cambiando el sodio y/o aluminio por cationes de similar naturaleza. El trabajo descrito en esta tesis se centra en estudiar la química de este tipo de compuestos incluyendo: la estabilidad en medios acuosos de las dawsonitas en condiciones moderadas, la obtención de compuestos nanoestructurados dawsonita-hidrotalcita a partir de hidrotalcita, y el efecto memoria de las alúminas derivadas de dawsonita. El objetivo final es la evaluación de los materiales sintetizados y sus derivados, en catálisis. Estos materiales han resultado ser eficientes o en algunos casos más activos que los catalizadores reportados en la literatura para reacciones básicas (la transesterificación de carbonato de etileno para producir carbonato de dimetilo) y redox (epoxidación de alquenos). Teniendo en cuenta los resultados obtenidos, estos materiales podrían ser utilizados como catalizadores, adsorbentes, y aditivos abriendo así una nueva vía de investigación. / Dawsonites are crystalline minerals generally present in nature as sodium aluminum carbonate hydroxide, NaAlCO3(OH)2. Besides the mineral, a variety of compositions with dawsonite-type structure have been synthesized by changing the nature of sodium or aluminum cations. The work described in this thesis focuses on the chemistry of dawsonite-type compounds including: the stability of dawsonites in aqueous media at mild conditions; the achievement of dawsonite-hydrotalcite nanostructured composites starting from the hydrotalcite; and the memory property of dawsonite-derived aluminas. The final goal is to evaluate the as-synthesized or derived dawsonite-materials in selected catalytic reactions. These materials were efficient or even more active than catalysts in the state-of-the-art in basic (dimethyl carbonate production by transesterification of ethylene carbonate with methanol) and redox (alkene epoxidation of cyclooctene with hydrogen peroxide) reactions. The above findings could have further practical implications as activated dawsonites open a new window of research with potential applications as catalysts, adsorbents, and additives.
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Interfacial chemistry of catechol-based nanostructuresGuardingo Melian, Mireia 06 November 2015 (has links)
Los catecoles son compuestos aromáticos presentes en una gran variedad de sistemas naturales. Dada su gran versatilidad a nivel de propiedades fisicoquímicas, adquieren papeles clave en diferentes procesos naturales. Entre otros, los grupos catecol se encuentran en las proteínas adhesivas de los mejillones formando parte de aminoácido L-DOPA, que se considera responsable del extraordinario poder adhesivo de estos organismos en condiciones de extrema humedad. Este fenómeno ha fascinado a los científicos durante décadas y grandes esfuerzos se han destinado a entender e imitar estos sistemas. Otras propiedades de los catecoles, como su capacidad de formar complejos metálicos o su actividad redox, también han sido estudiadas tanto a nivel fundamental como en sistemas aplicados.
En la presente tesis nos centramos en la obtención de sistemas de escala nanométrica basados en derivados de catecol y en el estudio de sus propiedades. Para ello, se llevó a cabo un trabajo multidisciplinar que incluye la síntesis de nuevos compuestos orgánicos, la obtención de nanoestructuras y el uso de microscopías y técnicas litográficas.
En primer lugar se estudió la influencia de la densidad y orientación de los grupos catecol en las propiedades interfaciales de monocapas autoensambladas (SAMs) con unidades de catecol en el exterior; usando una punta de AFM o mediante la adsorción de nanopartículas magnéticas. Además, se estudió el efecto de la unidad de catecol en el proceso de formación y la estructura final de las monocapas. Por otro lado se llevó a cabo la síntesis de materiales poliméricos nanoestructurados basados en la funcionalidad catecol. Para ello se emplearon tanto metodologías clásicas como la síntesis confinada en pequeños volúmenes en superficie mediante el uso de litografía por escritura directa asistida por AFM. Esta técnica nos permitió fabricar estructuras de polidopamina y partículas de polímeros de coordinación mediante la deposición en superficie de los precursores de estos materiales en forma de gotas en la escala del femtolitro. De esta forma demostramos la viabilidad de la técnica para posicionar materiales funcionales en áreas concretas de una superficie. / Catechols are aromatic derivatives present in a variety of environments in nature. Due to their broad physicochemical versatility, they play pivotal roles in multiple natural processes. Probably their most popular appearance is in the adhesive proteins of mussels in the form of the rare aminoacid L-DOPA, which is considered to be essential for the strong adhesion of mussels to surfaces under high humidity conditions. This phenomenon has fascinated scientists for decades and intensive research has been carried out in order to understand and mimic these systems. Furthermore, other chemical properties of catechols, such as their metal-chelating and redox behaviour have also been addressed for both fundamental understanding and practical application.
In this thesis we were interested in the obtention of nanoscale catechol-based systems and the study of their properties. For that, a multidisciplinary work was carried out which included the synthesis of new organic compounds, the preparation of nanostructures and the use of advanced microscopies and lithographic techniques.
The role of packing density and orientation of catechol moieties in the interfacial properties of catechol-terminated SAMs was studied at the local scale using an AFM tip or, alternatively, magnetic nanoparticles. The influence that the presence of the catechol ring has on the formation and final structure of SAMs was also addressed. On the other hand, the synthesis of catechol-based polymers in confined volumes was performed using direct-write AFM-assisted lithography. Polydopamine and coordination polymer particles were fabricated directly on surfaces by controlled delivery of their molecular precursors in the shape of femtolitre-sized droplets. With that, we demonstrated the viability of using this technique to place functional amorphous materials on specific areas of surfaces.
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Integrating plant oils in benzoxazine chemistry.Tuzun, Alev 13 March 2015 (has links)
Les polibenzoxazines son una classe relativament nova de resines fenòliques termoestables que posseeixen interessants propietats per a la indústria electrònica, automobilística, aerospacial i d’adhesius. Les seves possibilitats superen a les dels sistemes fenòlics clàssics, novolaques i resols, principalment en que no necessiten catalitzador per portar a terme el seu curat i no alliberen volàtils de condensació durant el mateix. Els monòmers benzoxazina es preparen habitualment per combinació de fenols i amines amb formaldehid mitjançant una condensació tipus Mannich. Aquesta química ofereix una elevada flexibilitat en el disseny estructural, fet que permet la utilització de gairebé qualsevol fenol i amina sigui comercial o sintètica. En aquesta tesi es persegueix la incorporació de derivats d’olis vegetals en monòmers i polímers precursors de polibenzoxazines per a que actuïn com a blocs flexibles. En concret, ens hem centrat en l’àcid 10-undecenoic i els seus derivats com a productes derivats de l’oli de resí, un oli vegetal no comestible. La incorporació d’aquest esquelet alifàtic, apart de d’incorporar productes derivats de fonts renovables a aquest tipus de polímers ha premés la preparació de materials flexibles. La rigidesa és una de les principals limitacions de las resines benzoxazina convencionals. Aquests objectius generals s’han aplicat a (i) monómers bis-benzoxazina sintetitzats a través de reaccions d’hidrosililació, (ii) monòmers bis-benzoxazina sintetitzats a través de reaccions d’auto-metátesi, i (iii) polímers que contenen grups benzoxazina en la cadena principal sintetitzats per polimerització de metátesi ADMET. / Las polibenzoxazinas son una clase relativamente nueva de resinas fenólicas termoestables que poseen interesantes propiedades para la industria electrónica, automovilística, aerospacial y de adhesivos. Sus posibilidades superan a los sistemas fenólicos clásicos, novolacas y resoles, principalmente en que no necesitan catalizador y no liberan volátiles de condensación durante su curado. Los monómeros benzoxazina se preparan habitualmente por combinación de fenoles y aminas con formaldehído vía una condensación tipo Mannich. Esta química ofrece una elevada flexibilidad en el diseño estructural por lo que permite la utilización que casi cualquier fenol o amina sea comercial o sintética. En esta tesis se persigue la incorporación de derivados de aceites vegetales como bloques flexibles en monómeros y polímeros precursores de polibenzoxazinas. En concreto, nos hemos centrado en el ácido 10-undecenoico y sus derivados como productos derivados del aceite de ricino, un aceite vegetal no comestible. La incorporación de este esqueleto alifático, aparte de incorporar las fuentes renovables a este tipo de polímeros ha permitido la preparación de materiales flexibles. La rigidez es una de las principales limitaciones de las resinas benzoxazina convencionales. Estos objetivos generales se han aplicado a (i) monómeros bis-benzoxazina sintetizados por reacción de hidrosililación, (ii) monómeros bis-benzoxazina sintetizados por reacción de auto-metátesis, y (iii) polímeros que contienen grupos benzoxazina en la cadena principal sintetizados por polimerización de metátesis ADMET / Polybenzoxazines are a relatively new class of thermosetting phenolic resins which possess properties of interest for several technological industries such as electronic, automobile, aerospace, and adhesives. Polybenzoxazine possibilities surpass those of the classical phenolic resins, novolacs and resoles, mainly because do not require a catalyst and eliminate condensation products release problems during curing. Benzoxazine monomers are classically prepared combining phenols and amines with formaldehyde via a Mannich-type condensation. Interestingly, this chemistry offers a tremendous flexibility in structural design allowing the use of almost any commercially available or synthetic phenol or amine. This thesis pursues the incorporation of plant oil derivatives as flexible segments into polybenzoxazine monomeric and polymeric precursors. In particular, we have focused on 10-undecenoic acid and its derivatives which are valuable renewable materials derived from non-edible castor oil. The incorporation of this aliphatic skeleton of fatty acids, apart from bringing biobased character to these materials, has allowed preparing inherently tough and flexible cured systems. Inflexibility is one of the main limitations of convetional polybenzoxazine resins. These general objectives were applied to three groups of polybenzoxazine precursors: (i) bis-benzoxazine monomers obtained by hydrosilylation reaction, (ii) bis-benzoxazine monomers obtained by self-metathesis reaction, and (iii) main chain benzoxazine polymers obtained by acyclic diene metathesis polymerization.
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Chemistry of Subporphyrin / サブポルフィリンの化学 / サブポルフィリン ノ カガクInokuma, Yasuhide 23 March 2009 (has links)
Kyoto University (京都大学) / 0048 / 新制・課程博士 / 博士(理学) / 甲第14406号 / 理博第3403号 / 新制||理||1498(附属図書館) / UT51-2009-D118 / 京都大学大学院理学研究科化学専攻 / (主査)教授 大須賀 篤弘, 教授 林 民生, 教授 丸岡 啓二 / 学位規則第4条第1項該当
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