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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.
151

Analysis of the nuclear magnetic resonance spectrum of 1,1,2,2-tetrafluoroethane /

Beisner, Henry Michaels January 1961 (has links)
No description available.
152

The solvothermal synthesis of early transition metal fluorides

Aldous, David W. January 2008 (has links)
In this thesis, 60 crystal structures which have been synthesised by the solvothermal method are reported, with 57 of them representing novel materials. The remaining three materials have previously been reported but have been made by a new and milder method of synthesis. Ti, Zr, Hf, V, Nb, Ta and Mo have all been used to make fluoride or oxyfluoride materials at temperatures ranging from 60C to 200C. Both inorganic and organic moieties ("templates") have been used to direct the formation of the (oxy)fluoride materials, usually as an anionic species. These materials have then been studied for their magnetic properties, where relevant. Initially, 10 vanadium-based compounds were made at 100C using a range of templates. Through variations in water content, temperature and cation ratio, a further 19 compounds were synthesised. The inorganic species in these structures ranged from monomers, to dimers, tetramers and chains, to infinite 2D sheets. A family of vanadium compounds has been synthesised, with piperazine as a template, which shows an increase in covalent connectivity through the increase of the reaction temperature, with a decrease in oxidation state as a result. These materials are also interrelated through the use of a "Y" shaped motif in their structural composition. Through a change in cation content a novel trigonal chain compound (related to the structure of CsCrF₄) has been synthesised with piperazine which possibly shows strong geometric frustration. Vanadium oxyfluoride analogues of (VO)₂P₂O₇ have been made, which show interesting magnetic properties with a range of different templates, ranging from alkali metal cations to the bulky protonated template trans 1,2 bis (4-pyridyl) ethene. The best fits to the magnetic susceptibility data are obtained with an antiferromagnetic Heisenberg chain model. Nine molybdenum-based structures have also been synthesised, with five of the structures being made through changes in the temperature and cation ratio of the reactions. An example of this is the formation of tetrameric units with ammonium, through the condensation of monomers as a result of an increase in the reaction temperature. A further 22 structures have also been made with metals, M = Ti, Zr, Hf, Nb and Ta. These structures have a tendency to form isolated polyhedral units under the conditions studied in this work. Several examples of isolated [MF₆][superscript n-] and [MF₇][superscript n-] monomers are reported and also one example of a trans-connected [TiOF₄]²⁻ infinite chain structure.
153

Estudo para a remocao de fluoreto em aguas e efluentes

CHARBEL, MARIA Y. 09 October 2014 (has links)
Made available in DSpace on 2014-10-09T12:36:21Z (GMT). No. of bitstreams: 0 / Made available in DSpace on 2014-10-09T13:59:29Z (GMT). No. of bitstreams: 1 03871.pdf: 2892098 bytes, checksum: 5369857479c6fb9952c9855c38d0ee35 (MD5) / Tese (Doutoramento) / IPEN/T / Instituto de Pesquisas Energeticas e Nucleares - IPEN/CNEN-SP
154

Sintese e crescimento de cristais fluoretos dopados com terras raras: LiCAF:Er e BLF:TR (TR = Yb sup(3+), Ce sup(3+), Nd sup(3+))

VIDAL, AUGUSTO T. 09 October 2014 (has links)
Made available in DSpace on 2014-10-09T12:46:16Z (GMT). No. of bitstreams: 0 / Made available in DSpace on 2014-10-09T14:01:47Z (GMT). No. of bitstreams: 1 07973.pdf: 3168450 bytes, checksum: 8bf87743d796e20893798cadfbfad208 (MD5) / Dissertacao (Mestrado) / IPEN/D / Instituto de Pesquisas Energeticas e Nucleares - IPEN/CNEN-SP
155

Estudo eletroquimico da co-reducao de KBFsub4 e Ksub2 TIFsub6 em meio de uma mistura eutetica de LiF-NaF-KF para a obtencao do diboreto de titanio [TIB sub 2]

ETT, GERHARD 09 October 2014 (has links)
Made available in DSpace on 2014-10-09T12:43:50Z (GMT). No. of bitstreams: 0 / Made available in DSpace on 2014-10-09T14:10:02Z (GMT). No. of bitstreams: 1 06778.pdf: 10838321 bytes, checksum: da09e815b4eb68ff38370a4f1987faaa (MD5) / Tese (Doutoramento) / IPEN/T / Instituto de Pesquisas Energeticas e Nucleares - IPEN/CNEN-SP
156

Estudo para a remocao de fluoreto em aguas e efluentes

CHARBEL, MARIA Y. 09 October 2014 (has links)
Made available in DSpace on 2014-10-09T12:36:21Z (GMT). No. of bitstreams: 0 / Made available in DSpace on 2014-10-09T13:59:29Z (GMT). No. of bitstreams: 1 03871.pdf: 2892098 bytes, checksum: 5369857479c6fb9952c9855c38d0ee35 (MD5) / Tese (Doutoramento) / IPEN/T / Instituto de Pesquisas Energeticas e Nucleares - IPEN/CNEN-SP
157

Sintese e crescimento de cristais fluoretos dopados com terras raras: LiCAF:Er e BLF:TR (TR = Yb sup(3+), Ce sup(3+), Nd sup(3+))

VIDAL, AUGUSTO T. 09 October 2014 (has links)
Made available in DSpace on 2014-10-09T12:46:16Z (GMT). No. of bitstreams: 0 / Made available in DSpace on 2014-10-09T14:01:47Z (GMT). No. of bitstreams: 1 07973.pdf: 3168450 bytes, checksum: 8bf87743d796e20893798cadfbfad208 (MD5) / Dissertacao (Mestrado) / IPEN/D / Instituto de Pesquisas Energeticas e Nucleares - IPEN/CNEN-SP
158

Estudo eletroquimico da co-reducao de KBFsub4 e Ksub2 TIFsub6 em meio de uma mistura eutetica de LiF-NaF-KF para a obtencao do diboreto de titanio [TIB sub 2]

ETT, GERHARD 09 October 2014 (has links)
Made available in DSpace on 2014-10-09T12:43:50Z (GMT). No. of bitstreams: 0 / Made available in DSpace on 2014-10-09T14:10:02Z (GMT). No. of bitstreams: 1 06778.pdf: 10838321 bytes, checksum: da09e815b4eb68ff38370a4f1987faaa (MD5) / Tese (Doutoramento) / IPEN/T / Instituto de Pesquisas Energeticas e Nucleares - IPEN/CNEN-SP
159

Estudo da acao laser de matrizes de fluoretos (LiSrAlF sub (6), Lu:LiYF sub (4)) dopadas com Cr sup (3+) e Nd sup (3+)

BARBOSA, EDUARDO A. 09 October 2014 (has links)
Made available in DSpace on 2014-10-09T12:45:36Z (GMT). No. of bitstreams: 0 / Made available in DSpace on 2014-10-09T14:08:38Z (GMT). No. of bitstreams: 1 07309.pdf: 6512485 bytes, checksum: da19e05a16a320b11188314140f1865c (MD5) / Tese (Doutoramento) / IPEN/T / Instituto de Pesquisas Energeticas e Nucleares - IPEN/CNEN-SP
160

Estudo da acao laser de matrizes de fluoretos (LiSrAlF sub (6), Lu:LiYF sub (4)) dopadas com Cr sup (3+) e Nd sup (3+)

BARBOSA, EDUARDO A. 09 October 2014 (has links)
Made available in DSpace on 2014-10-09T12:45:36Z (GMT). No. of bitstreams: 0 / Made available in DSpace on 2014-10-09T14:08:38Z (GMT). No. of bitstreams: 1 07309.pdf: 6512485 bytes, checksum: da19e05a16a320b11188314140f1865c (MD5) / Tese (Doutoramento) / IPEN/T / Instituto de Pesquisas Energeticas e Nucleares - IPEN/CNEN-SP

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