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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.
31

Studies on ion binding and ion exchange of proteins

Gilboe, David Dougherty, January 1958 (has links)
Thesis (Ph. D.)--University of Wisconsin--Madison, 1958. / Typescript. Vita. eContent provider-neutral record in process. Description based on print version record. Includes bibliographies: leaves 49-51, 72-74.
32

Mixed-bed ion exchange treatment of milk I. Effect on head stability of milk /

Mee, John M. L. January 1963 (has links)
Thesis (M.S.)--University of Wisconsin--Madison, 1963. / Typescript. eContent provider-neutral record in process. Description based on print version record. Includes bibliographical references (leaves 29-36).
33

The separation of interfering solutes by selective adsorption in fixed beds

Cooney, David O. January 1966 (has links)
Thesis (Ph. D.)--University of Wisconsin, 1966. / Typescript. Vita. eContent provider-neutral record in process. Description based on print version record. Includes bibliography.
34

Ion exchange separation of rhenium from molybdenum

Fisher, Sallie A. January 1949 (has links)
Thesis (Ph.D.)--University of Wisconsin--Madison, 1949. / Typescript. Vita. eContent provider-neutral record in process. Description based on print version record. Includes bibliographical references (leaves 157-158).
35

Co-ion transport through anion exchange membranes

Christensen, Edward Louis, January 1968 (has links)
Thesis (Ph. D.)--University of Wisconsin--Madison, 1968. / Includes reprint of Exchange equilibrium through anion exchange membranes [by] W.J. Blaedel and E.L. Christensen, from Analytical chemistry, vol. 39, p. 1262, September 1967. Typescript. Vita. eContent provider-neutral record in process. Description based on print version record. Includes bibliography.
36

The hydrolysis of cyanopyridinium ions

Patton, James Winton, January 1961 (has links)
Thesis (Ph. D.)--University of Wisconsin--Madison, 1961. / Typescript. Vita. eContent provider-neutral record in process. Description based on print version record. Includes bibliographical references.
37

Simulation of sorption processes.

Svedberg, Gunnar. January 1975 (has links)
Thesis--Tekniska Högskolan i Stockholm. / Includes bibliographical references.
38

The development of a quinquaquadrupole mass spectrometer : the study of ion-molecule reactions in the gas phase using multiple quadrupole instruments

Hall, Robin Gibson January 1991 (has links)
The field of quadrupole mass spectrometry has grown enormously since the early 1980's. The invention of the triple quadrupole mass spectrometer led to the development of tandem quadrupole mass spectrometers of many different configurations. A large number of tandem quadrupole mass spectrometers have also been developed by linking one or more quadrupole mass filters to a traditional magnetic or electric filter. The versatility of multiple quadrupole mass spectrometers along with their potential to rapidly produce a huge amount of data on a particular ion makes them ideal instruments for routine analytical analysis as well as for fundamental research The quinquaquadrupole mass spectrometer has been developed as an extension to the available multiple quadrupole systems. It offers the possibility to obtain even more data on the fragmentation of ions as well as enabling the study of novel ions to be carried out. The development of the quinquaquadrupole mass spectrometer forms the main part of this thesis. Also discussed are the reactions studied to evaluate the instrumental performance. The the ion molecule reactions of some halogen containing cations with saturated and unsaturated hydrocarbons performed on the triple quadrupole mass spectrometer are also discussed.
39

Investigations of some energy transfer processes associated with acetylacetonate complexes of the lanthanoid and groups I and II metal ions

Neilson, John Duncan January 1979 (has links)
Intermolecular energy transfer occurs between Tb(aa)3.3H20 and Ln(aa)3.3H2O complexes (Ln = Pr, Nd, Sm, Eu, Dy, Ho or Er; aa = acetylacetonate) in n-butanol solution at 293K. Measurement of the decay time of the Tb3+ 5D4level indicates that transfer occurs from this level to excited levels of the Ln3+ ions with bimolecular rate constants within the range 0.5 - 4.9 x 105 dm3 mol s −1. Data from similar measurements on a mixed crystal EuxTb(1-x)(aa)3.3H2O and other considerations indicate that this is a very short range electron-exchange transfer. Similar measurements of the Tb3+ ion phosphorescence yield indicate the presence of a further intermolecular transfer process between a higher excited state of the Tb3+ complex and the added Ln3+ complexes. The Stern-Volmer Quenching constants vary from 11 dm3 mol−1 for Ho and Sm to 110 dm3 mol−1 for Pr. It is concluded that this transfer is unlikely to occur from either the ligand singlet or triplet levels and it is proposed that a higher Tb3+ level such as the 5D3 may be involved in both inter- and intramolecular energy transfer. Intermolecular energy transfer between excited state Tb3+ ions in Tb(aa)3.3H2O and Ln3+ ions in Ln(aa)3.3H2O, where Ln = Eu and Sm, is shown to be markedly solvent dependent. It is proposed that the Tb3+ → Ln3+ energy transfer occurs in mixed metal dimers where the Tb-Ln distance is likely to be ca. 0.4 nm. The solvent dependent behaviour is related to the relative concentrations of monomeric and dimeric species in the various solvents. The rate controlling step in the intermolecular energy transfer is probably that, of monomer-dimer reaction which at 273K is of the order of 105 dm3 mol−1 s−1. The activation energy of this reaction between Tb, Eu and Sm acetylacetonates is estimated to be ca. 23 kJ mol−1. 1H NMR spectra of Lu(aa)3.2H2O in several solvents are reported. The spectral profiles are temperature dependent in benzene and toluene solutions and the multiplicity of ligand methyl resonances is attributed to slow exchange between non-equivalent methyl groups in a dimeric structure. The temperature dependence in acetone solution is consistent with the presence of a monomer-dimer equilibrium with △H° = -28.2 ± 1.5 kJ mol−1 and △S° = -74.5 ± 4.5 J K −1 mol−1. The single ligand-methyland 3-H resonances in the' strongly coordinating solvents dimethyl sulphoxide and pyridine indicate the sole presence of solvated monomers. Previous proposals about the anomalous spectrum of Mg(aa)2 in CDCl3 are also discussed. The extremely low efficiency of the intermolecular enrgy transfer process in europium acetylacetonate compared with the corresponding terbium acetylacetonate is attributed to the presence of a charge-transfer excited state lying below the ligand singlet states. This is supported by the anomalous absorption spectrum of the Eu3+complex and the effects of added anions in other ligand systems. The phosphorescence spectra of the Group I and Group II metal acetylacetonates (Metal = Li, Na, K, Rb, Gs, Mg, Ca, Sr and Ba) have all been measured in solid Ethanol glass solutions at 77K and found to have profiles similar to that of Al(aa)3. The phosphorescence decays are non-exponential and this behaviour is attributed to the presence of both coordinated and free acetylacetonate anion. Time resolved spectroscopy and other considerations indicate that the energies of the lowest excited ligand singlet and triplet states of the aa− ion are, unlike the triplet state lifetime, little affected by coordination. Solvolysis is reported in ethanol solution which invalidates some previously-reported spectral parameters.
40

Comportamento de cobre (II) e uranio (VI) em cromatografia de precipitacao no sistema resina anionica forte-hexacianoferrato (II)

SENEDA, JOSE A. 09 October 2014 (has links)
Made available in DSpace on 2014-10-09T12:41:03Z (GMT). No. of bitstreams: 0 / Made available in DSpace on 2014-10-09T14:10:17Z (GMT). No. of bitstreams: 1 04033.pdf: 2633354 bytes, checksum: f9347be894a819791c1c4ebbed150b1e (MD5) / Dissertacao (Mestrado) / IPEN/D / Instituto de Pesquisas Energeticas e Nucleares - IPEN/CNEN-SP

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