Global ETD Search
Search theses and dissertations gathered from participating repositories worldwide. Every result links back to the library that holds it. No account is needed.
Results
Showing 1 to 15 of 15 for “"Mossbauer spectra"”.
-
Quantitative Mossbauer spectra and chemistry of iron,
Thesis (Ph. D.)--Massachusetts Institute of Technology, Dept. of Earth and Planetary Science, 1974.
-
Determination of Recoil-Free Fractions From 151Eu Mossbauer Spectra of EuBO3
Emission of a gamma ray from a nucleus is a result of a nuclear transition from one energy level to another. If the emitting nucleus is not bound in a crystal lattice, some of the transition energy, or the difference in energy of the two nuclear levels, may be imparted to the nucleus as it recoils, …
-
The effect of high pressure on the quadrupole interaction in iron-fluorine compounds
Using the inter-atomic distance as a parameter, Mossbauer spectra have been observed for the three isomorphic ferric compounds K3FeF6, Na3 FeF6 and (NH4)3FeF6' In addition, the compressibility and the pressure dependence of cia were determined by X-ray diffraction for the ferrous compound FeF2 , In …
-
The Effect of The Solid-State Environment on Intramolecular Electron-Transfer Rates in Mixed-Valence Complexes (Ferrocene)
… transfers electrons slower than the Mossbauer time scale at 340 K. On the other hand, dibromo- and diiodobiferrocenium triiodide salts transfer electrons faster than the Mossbauer time scale not only at 298 K, but also all the way down to 4.2 K. Finally, mixed-valence triiodide salts …
-
ΜΕΛΕΤΗ ΤΗΣ ΕΠΙΔΡΑΣΗΣ ΤΗΣ ΠΑΡΑΣΚΕΥΑΣΤΙΚΗΣ ΔΙΑΔΙΚΑΣΙΑΣ ΣΤΙΣ ΦΥΣΙΚΟΧΗΜΙΚΕΣ ΙΔΙΟΤΗΤΕΣ ΤΩΝ ΦΕΡΡΙΤΩΝ ΤΩΝ ΣΤΟΙΧΕΙΩΝ ΤΗΣ ΣΕΙΡΑΣ ΤΩΝ ΛΑΝΘΑΝΙΔΩΝ. ...
… ANALYSIS, EXAMINATION OF THESAMPLES BY X-RAY AND MOSSBAUER SPECTRA AND MAGNETIC SUSCEPTIBILITY MEASUREMENTS. SPECIAL ATTENTION WAS GIVEN TO THE STUDY OF THEIR CATALYTIC PROPERTIES AND THE REACTION CHOSEN WAS THE THERMAL DECOMPOSITION OF POTASSIUM AND SODIUM CHLORATES AND PERCHLORATES. IT WAS FOUND …
-
A Mossbauer study of divalent iron in silver chloride crystals
… rate has been investigated by means of the Mossbauer effect for divalent iron, initially diffused as S7Co into single crystals of silver chloride. The divalent iron ion substitutes for the monovalent silver ion and associates with a charge compensating positive ion vacancy in a next nearest …
-
Model complexes for active sites of diiron metalloproteins, dioxygen reactivity and water effects
… with the enzyme, electronic transitions, Mossbauer spectra, and magnetic exchange interactions. On the other hand, the structure of 4, ([mu]-oxo)([mu]-carboxylato)diiron(III) complex, mimics the diiron(III) sites of RNR-R2. The electronic and Mbssbauer spectral transitions of 4 are typical …
-
Modeling the active sites of diiron and dicopper metalloproteins with napthyridine-, phthalazine-, and diethynylbenzene-based ligands
… anti to a syn, syn coordination mode, and the Mossbauer spectra of the diiron(II) compounds clearly reflect the symmetry of the iron coordination environment. The oxidation chemistry of the diiron(II) compounds is presented.
-
Dioxygen activation and substrate hydroxylation by the hydroxylase component of toluene/O-xylene monooxygenase from pseudomonas sporium OX1
… investigated by rapid-freeze quench (RFQ) EPR, Mossbauer, and ENDOR spectroscopy and stoppedflow optical spectroscopy. For the I100W mutant, a transient species is observed with an absorption maximum at 500 nm. EPR and Mossbauer spectra of RFQ samples identified this species as a diiron(III,IV) …
-
The Mossbauer effect in iron under very high pressure
The Mossbauer spectrum of Fe57 in iron metal has been measured at pressures up to 240 kilobars at room temperature. Below 133 kilobars the spectrum consists of the normal six lines characteristic of ferromagnetic, body-centered cubic iron. The internal magnetic field at the nucleus H decreases …
-
Environmental effects on the rate of intramolecular electron transfer in trinuclear mixed-valence transition metal carboxylate complexes in the solid state
… exhibits a phase transition at 125K. $\sp{57}$Fe Mossbauer spectra of this CHCl$\sb3$ solvate complex show that this complex valence-detraps at $\sim$95K. However, the complex with the less symmetric CH$\sb3$CHCl$\sb2$ solvate molecule becomes valence-detrapped at $\sim$45 degrees higher than for …
-
A study into the fundamental understanding of iron-transformations and the effect of iron as fluxing agent on Highveld fine coal sources during gasification
… present in the coal was studied by means of Mossbauer spectroscopy. Typical characterisation analyses were also carried out on the original coal samples. The ash fusion temperature analyses (AFT) were used to study the slagging behaviour of the iron-spiked coal samples. Even though AFT …
-
Mossbauer studies of spin coupled binuclear iron centers in proteins
… derivatives of hemerythrin have been studied by Mossbauer Spectroscopy. Simulations of data recorded in applied fields for the 4.2 K to 250 K temperature range have been performed with the intrinsic spin Hamiltonian $\rm {\cal H} = J{\bf S}\sb1\cdot{\bf S}\sb2 + \Sigma\sbsp{i=1}{2}\{{\bf …
-
Organo-iron compounds on clays and pillared clays.
… montmorillonite Westone-L. Variable temperature Mossbauer spectroscopy indicated that the molecule had a similar Debye temperature in each environment (144 +/- 5 K and 140 +/- 5 K respectively). The intercalated Mossbauer spectra revealed a Karayagin effect above 80 K. The cation occupies 80 % of …
-
PHOSPHATE ADSORPTION AND DESORPTION ON TWO CONTRASTING SOILS USED FOR LAND TREATMENT OF WASTEWATER
… concentrations of Fe (II) and Fe (III) by Mossbauer spectroscopy was examined. Mossbauer spectra were obtained which demonstrate the successful application of the technique to the study of reduced iron in soils.</p>