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Raman spectroscopy is an excellent technique for probing lithium intercalation reactions of many diverse lithium ion battery electrode materials. The technique is especially useful for probing LiFePO 4 -based cathodes because the intramolecular vibrational modes of the PO 4 3− anions yield intense bands in the Raman spectrum, which are sensitive to the presence of Li + ions. However, the high power lasers typically used in Raman spectroscopy can induce phase transitions in solid-state materials. These phase transitions may appear as changes in the spectroscopic data and could lead to erroneous conclusions concerning the delithiation mechanism of LiFePO 4 . Therefore, we examine the effect of exposing olivine FePO 4 to a range of power settings of a 532-nm laser. Laser power settings higher than 1.3 W/mm 2 are sufficient to destroy the FePO 4 crystal structure and result in the formation of disordered FePO 4 . After the laser is turned off, the amorphous FePO 4 compound crystallizes in the electrochemically inactive α-FePO 4 phase. The present experimental results strongly suggest that the power setting of the excitation laser should be carefully controlled when using Raman spectroscopy to characterize fundamental lithium ion intercalation processes of olivine materials. In addition, Raman spectra of the amorphous intermediate might provide insight into the α-FePO 4 to olivine FePO 4 phase transition that is known to occur at temperatures higher than 450 • C.

Siderophore production by marine-derived fungi has not been extensively explored. Three studies have investigated the ability of marine-derived fungi to produce siderophores in response to iron limitation [(Vala et al. in . In all, 24 of 28 marine fungal strains were found to secrete hydroxamate or carboxylate siderophores; no evidence was found for production of catecholate siderophores. These studies did not determine the structures of the iron-binding compounds. More recently, a study of the natural products secreted by a marine Penicillium bilaii revealed that this strain produced the rare catecholate siderophore pistillarin when grown under relatively high iron concentrations (Capon et al. J Nat Prod 70:1746-1752, 2007. Additionally, the production of rhizoferrin by a marine isolate of Cunninghamella elegans (ATCC36112) is reported in this manuscript. The current state of knowledge about marine fungal siderophores is reviewed in light of these promising results.

We report the growth of single-phase (0001)-oriented epitaxial films of the purported electronically driven multiferroic, LuFe2O4, on (111) MgAl2O4, (111) MgO, and (0001) 6H-SiC substrates. Film stoichiometry was regulated using an adsorption-controlled growth process by depositing LuFe2O4 in an iron-rich environment at pressures and temperatures where excess iron desorbs from the film surface during growth. Scanning transmission electron microscopy reveals reaction-free film-substrate interfaces. The magnetization increases rapidly below 240 K, consistent with the paramagnetic-to-ferrimagnetic phase transition of bulk LuFe2O4. In addition to the ∼0.35 eV indirect band gap, optical spectroscopy reveals a 3.4 eV direct band gap at the gamma point.