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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.
121

Synthesis and characterisation of transition metal fluorides

Black, Cameron January 2015 (has links)
This thesis reports exploratory studies on the synthesis of new vanadium and copper-containing compounds, with a particular emphasis on preparing new magnetically-active materials with S = ½ spin configurations. Eighteen crystal structures are reported, sixteen of which represent new compounds. These materials were studied for magnetic behaviour where appropriate. The sixteen vanadium-containing compounds were prepared using either the hydrothermal, Solvothermal or ionothermal synthesis methods at temperatures ranging from 60 °C to 200 °C. Inorganic cations and organic moieties were used as templating agents to direct the structures, often targeting potentially frustrated lattices based on triangular motifs by using ‘triangular' templating molecules such as guanidine. Solvent choices, as well as reactant ratios were all varied in order to produce the new oxide, fluoride and oxyfluoride compounds of vanadium. Three families of vanadium compounds were prepared from these methods; a family of 1D vanadium (IV) oxyfluoride ladder compounds of general formula AVOF₃ (A=K⁺, Rb⁺, Cs⁺ or NH₄⁺), and a family of 1D vanadium fluoride chain compounds of general formula A₂VF₅ (A=K⁺ or NH₄⁺). The third family is comprised of three vanadium-containing compounds of varying dimensionality that share guanidine as the common organic moiety. Several miscellaneous compounds of vanadium such as clusters and a new V (IV) layer were synthesized, and are reported. The two copper compounds containing compounds, analogous to the pseudo-kagome compound, Cu₃Bi(SeO₃)₂O₂Br, were prepared via solid-state techniques. A detailed neutron diffraction study was carried out on the two compounds to measure the evolution of the magnetic properties from room temperature down to 2.5 K. Representational analysis was utilised in order to provide a detailed magnetic model of the compounds.
122

Termoluminescencia do LiF: Mg, Ti entre 66 e 315 K

ROSA, LUIZ A.R. da 09 October 2014 (has links)
Made available in DSpace on 2014-10-09T12:36:38Z (GMT). No. of bitstreams: 0 / Made available in DSpace on 2014-10-09T13:59:10Z (GMT). No. of bitstreams: 1 01821.pdf: 4038166 bytes, checksum: ede612636a13b46e2d052cfc50e01907 (MD5) / Tese (Doutoramento) / IPEN/T / Instituto de Fisica, Universidade de Sao Paulo - IF/USP
123

Dosimetria termoluminescente de neutrons termicos com CaF-2+KBr e CaSO-4:Dy+KBr

LEITE, ANA M.P. 09 October 2014 (has links)
Made available in DSpace on 2014-10-09T12:29:45Z (GMT). No. of bitstreams: 0 / Made available in DSpace on 2014-10-09T14:00:04Z (GMT). No. of bitstreams: 1 00456.pdf: 1075435 bytes, checksum: 5890a1018150d05979ee39919f44ca34 (MD5) / Dissertacao (Mestrado) / IEA/D / Instituto de Energia Atomica - IEA
124

Mecanismo proposto de termoluminescencia induzida pela luz UV no fluoreto de calcio natural

LAS, WANDA C. 09 October 2014 (has links)
Made available in DSpace on 2014-10-09T12:24:18Z (GMT). No. of bitstreams: 0 / Made available in DSpace on 2014-10-09T14:04:26Z (GMT). No. of bitstreams: 1 00508.pdf: 1394827 bytes, checksum: 4841c122d3cfa0b91639516519105971 (MD5) / Dissertacao (Mestrado) / IEA/D / Instituto de Fisica, Universidade de Sao Paulo - IF/USP
125

Propriedades de termoluminescencia do LiF:Mg

WATANABE, SHIGUEO 09 October 2014 (has links)
Made available in DSpace on 2014-10-09T12:24:54Z (GMT). No. of bitstreams: 0 / Made available in DSpace on 2014-10-09T14:04:54Z (GMT). No. of bitstreams: 1 01042.pdf: 2867797 bytes, checksum: 7d025b68770b969cf1af56bb1194ce50 (MD5) / Tese (Livre docencia) / IEA/T / Faculdade de Filosofia Letras e Ciencias Humanas, Universidade de Sao Paulo - FFLCH/USP
126

Dano de radiacao em CaF2:Gd

PRADO, LUCIA 09 October 2014 (has links)
Made available in DSpace on 2014-10-09T12:29:58Z (GMT). No. of bitstreams: 0 / Made available in DSpace on 2014-10-09T14:10:00Z (GMT). No. of bitstreams: 1 00719.pdf: 1100089 bytes, checksum: 52bcccbf50c4b3fe75b7220f72710e78 (MD5) / Dissertacao (Mestrado) / IEA/D / Instituto de Energia Atomica - IEA
127

Termoluminescencia do LiF: Mg, Ti entre 66 e 315 K

ROSA, LUIZ A.R. da 09 October 2014 (has links)
Made available in DSpace on 2014-10-09T12:36:38Z (GMT). No. of bitstreams: 0 / Made available in DSpace on 2014-10-09T13:59:10Z (GMT). No. of bitstreams: 1 01821.pdf: 4038166 bytes, checksum: ede612636a13b46e2d052cfc50e01907 (MD5) / Tese (Doutoramento) / IPEN/T / Instituto de Fisica, Universidade de Sao Paulo - IF/USP
128

Dosimetria termoluminescente de neutrons termicos com CaF-2+KBr e CaSO-4:Dy+KBr

LEITE, ANA M.P. 09 October 2014 (has links)
Made available in DSpace on 2014-10-09T12:29:45Z (GMT). No. of bitstreams: 0 / Made available in DSpace on 2014-10-09T14:00:04Z (GMT). No. of bitstreams: 1 00456.pdf: 1075435 bytes, checksum: 5890a1018150d05979ee39919f44ca34 (MD5) / Dissertacao (Mestrado) / IEA/D / Instituto de Energia Atomica - IEA
129

Mecanismo proposto de termoluminescencia induzida pela luz UV no fluoreto de calcio natural

LAS, WANDA C. 09 October 2014 (has links)
Made available in DSpace on 2014-10-09T12:24:18Z (GMT). No. of bitstreams: 0 / Made available in DSpace on 2014-10-09T14:04:26Z (GMT). No. of bitstreams: 1 00508.pdf: 1394827 bytes, checksum: 4841c122d3cfa0b91639516519105971 (MD5) / Dissertacao (Mestrado) / IEA/D / Instituto de Fisica, Universidade de Sao Paulo - IF/USP
130

Propriedades de termoluminescencia do LiF:Mg

WATANABE, SHIGUEO 09 October 2014 (has links)
Made available in DSpace on 2014-10-09T12:24:54Z (GMT). No. of bitstreams: 0 / Made available in DSpace on 2014-10-09T14:04:54Z (GMT). No. of bitstreams: 1 01042.pdf: 2867797 bytes, checksum: 7d025b68770b969cf1af56bb1194ce50 (MD5) / Tese (Livre docencia) / IEA/T / Faculdade de Filosofia Letras e Ciencias Humanas, Universidade de Sao Paulo - FFLCH/USP

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