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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
161

Optimisation et caractérisations de poudres de nickelates de terre rare et leur application pour la furtivite infrarouge / Optimization and characterization of earth rare nickelate powder their applications for infrared furtivity

Dutfoy, Cécile 10 December 2009 (has links)
Les nickelates de terre – rare, présentent une transition métal - isolant abrupte dont la température dépend de la composition. Cette transition se traduit dans le domaine infrarouge par le passage d'un comportement opaque à transparent en fonction de la température. Cette propriété se traduit par des contrastes en émissivité et présente un intérêt dans le domaine de la furtivité infrarouge. Le travail présenté porte sur la validation d’une solution solide de nickelate de terre rare de formule Nd0,3Sm0,7NiO3 sous forme de pigments actifs pour la furtivité infrarouge. Dans un premier temps, nous avons cherché à optimiser le procédé de synthèse en nous intéressant à la pression d’oxygène durant le recuit sous pression. Nous avons caractérisé les propriétés structurales de chaque lot de poudre synthétisée..La seconde partie est consacrée aux propriétés thermo – optique de Nd0,3Sm0,7NiO3 sous différentes mis en forme (céramique, poudre, film hybride). La dernière partie à proposer des simulations de comportement optique de pigment de Nd0.3Sm0.7NiO3 dans différentes matrices. / The rare – earth nickelats exhibit a sharp metal – insulator transition whose temperature depends on the composition. This transition is responsible, in the infrared range, of the . This work deals with the validation of nd0,3Sm0,7NiO3 powders like active pigments for the infared furtivity. The first part consists of the optimisations of synthesis process by reducting the oxygen pressure during the annealing. We have characterized the structural properties of each batch synthetized. The second part presents the thermo – optical properties of …. The last part proposes some simulations of the optical behaviour of Nd0,3Sm0,7NiO3 in various matrix.
162

Uso da dialise no fracionamento de terras raras

FERREIRA, JOAO C. 09 October 2014 (has links)
Made available in DSpace on 2014-10-09T12:49:05Z (GMT). No. of bitstreams: 0 / Made available in DSpace on 2014-10-09T14:09:55Z (GMT). No. of bitstreams: 1 09625.pdf: 6160972 bytes, checksum: 2ae10c10ff511fd097547d0090886d18 (MD5) / Dissertacao (Mestrado) / IPEN/D / Instituto de Pesquisas Energeticas e Nucleares - IPEN/CNEN-SP
163

Responsive luminescence toolbox for biological applications

Li, Hongguang 15 February 2016 (has links)
In chapter one, literature review have been down about the photophysical properties of lanthanide complexes and their applications. In chapter 2, the design and synthesis of water soluble cyclen based europium complexes with cyclin A specific peptides were described. Linear and two-photon induced hypersensitive europium emission gave the real time signalling and also enhanced the two-photon induced emission from 12GM to 68GM after Cyclin A binding. In chapter 3, the design of water soluble multi-modal porphyrin based compounds for key cell cycle regulator- Plk 1 imaging and cancer cells inhibition were described. Two water soluble porphyrin compounds have been synthesized and shown the specific photodynamic therapy treatment in the cancer cells via the selectively binding with Polo-like kinase 1 (Plk1). Plk1 is responsible for cell cycle regulation. Commercial or known Plk1 inhibitor/bioprobes are always poor cell internalization and easily to be damaged by enzymatic degradation. In addition, these markers are not available to image and inhibit the Plk1 as dual function probe. We introduced a new approach amphiphilic porphyrin with Plk1 specific peptide. Our compounds shown responsive emission enhancement upon binding with Plk1 in aqueous medium. In vitro, it can triggered G2-M phase arrest and inhibited the cancer cells specific as Plk1 is overexpressed in cancer cell. In chapter 4, we designed and synthesized a platinumeuropium complex (PtEuL401) as a controlled delivery vehicle of cisplatin. PtEuL401 shown responsive emission with the appropriate light excitation in aqueous and in vivo during the drug delivery process. Compared with the existing prodrugs, we offer real-time monitoring of the therapy process. Also, the long emission lifetimes of lanthanides creates room for further development in time-resolved imaging protocols which eliminates the problem of autofluorescence.
164

Compostos de adicao dos percloratos de elementos lantanidicos e de itrio com a N, N, N', N', tetrametilamida do acido ftalico (TMAF)

SILVA, CONSTANCIA P.G. da 09 October 2014 (has links)
Made available in DSpace on 2014-10-09T12:23:21Z (GMT). No. of bitstreams: 0 / Made available in DSpace on 2014-10-09T13:56:06Z (GMT). No. of bitstreams: 1 00618.pdf: 1570584 bytes, checksum: 5629fbad13048030f32991bd56f64a58 (MD5) / Tese (Doutoramento) / IEA/T / Instituto de Quimica, Universidade de Sao Paulo - IQ/USP
165

Uso da dialise no fracionamento de terras raras

FERREIRA, JOAO C. 09 October 2014 (has links)
Made available in DSpace on 2014-10-09T12:49:05Z (GMT). No. of bitstreams: 0 / Made available in DSpace on 2014-10-09T14:09:55Z (GMT). No. of bitstreams: 1 09625.pdf: 6160972 bytes, checksum: 2ae10c10ff511fd097547d0090886d18 (MD5) / Dissertacao (Mestrado) / IPEN/D / Instituto de Pesquisas Energeticas e Nucleares - IPEN/CNEN-SP
166

Synthesis, photophysical and biological studies of lanthanide complexes for photodynamic therapy

Zhou, Yan 14 September 2017 (has links)
1.2\xPrior to the PDT, we have also synthesized a series of water-soluble homoleptic lanthanides (Ln3+ = Gd, Er, and Yb) sandwich (DD) di-PEGylated porphyrin complexes. The Yb complex (YbDD) has shown the same NIR emission quantum yield as the highest record Yb complex in the literature (Yb-RhB), yet, the emission intensity is double compared to the Yb-N. This implies a new thinking about the quantity measurement for biological imaging. The brightness might be the prime factor for the development of luminescence in vitro/in vivo imaging agent rather than the emission quantum yield.
167

Repurposing Clinic-Tested Drugs to Treat Rare Neurogenetic Diseases by Transcriptional Modulation

Hadwen, Jeremiah 03 May 2018 (has links)
Rare diseases caused by single-gene mutations affect almost one million Canadians. According to the Online Mendelian Inheritance in Man database, ~4,500 rare monogenic diseases have a known cause; but less than 5% of patients have access to disease-modifying drugs. The dearth of accessible drugs for patients suffering from rare genetic diseases is partly due to the astronomical costs of traditional drug development which, when combined with the small target population, make rare disease therapeutics unattractive ventures for the pharmaceutical establishment. The paucity of cost-effective treatments for rare diseases has resulted in the promotion of clinic-ready drug repurposing as a tenable strategy for rare disease therapeutics. To identify repurposed candidates for rare neurogenetic diseases, I conducted a transcriptome-wide drug screen in mouse primary cerebrocortical cultures. RNA sequencing was used to develop a database of transcriptome-wide differential expression for 218 clinic-tested drugs. The “Neuron Screen” database was queried to identify drugs that upregulate ~60 rare neurogenetic disease genes (type I hits). Gene set enrichment pathway analysis by Ingenuity Pathway Analysis (IPA) was used to identify network associated drug-gene interactions (type II hits). Both types of drug-gene hits were further assessed in vitro and in vivo by qRT-PCR and western blot analysis. This analysis showed that the IPA-based network-associated approach reduces the false positive rate when identifying differentially expressed genes in transcriptome-wide data-sets. The analysis also identified two drug-gene interactions with genes that cause rare neurogenetic disease, thyroid hormone-Pmp22 and dexamethasone-Mfsd2a, that merit further investigation. This work proves the utility of the Neuron Screen database to connect rare disease genes with transcript-modulating drugs and provides a starting point to understand the transcriptional effects of pharmacologic agents on the mammalian brain.
168

Neutron diffraction and ultrasonic studies of magnetic ordering in rare earths

Brits, George Hendrik Frederik 04 February 2014 (has links)
D.Phil. (Physics) / Please refer to full text to view abstract
169

Synthesis, crystal structures and molecular modelling of rare earth complexes with bis(2-pyridylmethyl)amine: aim topological analysis and ligand conformation search

Matthews, Cameron January 2017 (has links)
Eight rare earth complexes with bis(2-pyridylmethyl)amine (DPA) were synthesised and recrystallised, under air-sensitive or low moisture conditions. The crystal structures were successfully determined, via SC-XRD, and the asymmetric units of five complexes (1, 3, 5, 6 and 7) were submitted for DFT molecular modelling calculations, which involved geometry optimisation and frequency calculations. The neutral complexes obtained were bis(bis(2-pyridylmethyl)amine)-trichloro-lanthanum(III) [LaCl3(DPA)2] (1), bis(bis(2-pyridylmethyl)amine)-trichloro-cerium(III)) [CeCl3(DPA)2] (2), bis(μ2-chloro)-diaqua-tetrachloro-bis(bis(2-pyridylmethyl)amine)-di-praseodymium(III) [PrCl2(μ-Cl)(DPA)(OH2)]2 (3) and bis(μ2-methoxo)-bis(bis(2-pyridylmethyl)amine)- tetrachloro-di-dysprosium(III) [DyCl2(μ-OCH3)(DPA)]2 (4). The cationic complexes obtained in this study were dichloro-bis(bis(2-pyridylmethyl)amine)- neodymium(III) chloride methanol solvate [NdCl2(DPA)2]Cl·CH3OH (5), dichloro-bis(bis(2- pyridylmethyl)amine)-dysprosium(III) chloride methanol solvate [DyCl2(DPA)2]Cl·CH3OH (6), dichloro-bis(bis(2-pyridylmethyl)amine)-yttrium(III) chloride methanol solvate [YCl2(DPA)2]Cl·CH3OH (7) and dichloro-bis(bis(2-pyridylmethyl)amine)-lutetium(III) chloride methanol solvate [LuCl2(DPA)2]Cl·CH3OH (8). The ‘Quantum theory of atoms in molecules’ approach was used to investigate the electron density topology, primarily in order to investigate the hydrogen and coordination bonds for three of the eight complexes. Two of the neutral complexes contain the ‘early’ rare earth elements lanthanum and praseodymium and one cationic complex contains the ‘late’ lanthanide element dysprosium. Noncovalent interaction analysis was also performed on the aforementioned complexes in order to gain a deeper understanding of the intra-molecular stereo-electronic interactions. Spin density analysis was used to investigate the distribution of unpaired electron density at and around the metal centres of the aforementioned paramagnetic Pr- and Dy-complexes. A ligand conformation search for DPA was undertaken and 32 low energy conformers were identified and their relative energies were determined using two DFT functionals, namely M06 and M06-2X.
170

Experimental Investigations Of Rare Earth Manganates And Other Oxide Systems

Seikh, Md Motin 08 1900 (has links) (PDF)
No description available.

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