Cel The magnetization of hydrogen nuclei in H2O constitutes the basis of most applications of magnetic resonance imaging (MRI.) Only ortho-water, where the two proton spins are in states that are symmetric with respect to permutation, features NMR-allowed transitions. Para-water is analogous to para-hydrogen, where the two proton spins are anti-symmetric with respect to permutation. The objective of this proposal is to render para-H2O accessible to observation. Several strategies will be developed for its preparation and observation in solids, liquids and gas phase, with yields up to 33%. When diluted in acetonitrile at room temperature, we found that Tortho(H2O) = 6 s. Based on experiments on H2C groups where Tpara/Tortho > 37, we conservatively estimate that Tpara/Tortho > 10 for H2O, so that we expect Tpara = 60 s. Dilution in aprotic solvents inhibits the exchange of protons and extends the lifetimes t(H2O) of water molecules from ca. 1 ms in pure water to 10 s and beyond, so that proton exchange does not hamper the use para-water. The ratio Tpara/Tortho of H2O depends on temperature, viscosity, paramagnetic agents, etc., which affect intra- and inter-molecular dipole-dipole interactions, chemical shift anisotropy, and spin rotation. In cases where proton exchange significantly shortens the lifetime of para-H2O, we shall prepare and observe para-ethanol and aqueous solutions of para-glycine, which cannot suffer from proton exchange, and allow similar perspectives as para-water. In conventional MRI, contrast stems mostly from spatial variations of T1 and T2. By monitoring the ratio Tpara/Tortho as a function of spatial coordinates, it will be possible to obtain a novel type of contrast. In suitable phantoms and porous media, para-water will allow us to characterize slow transport phenomena such as flow, diffusion, and electrophoretic mobility. The study of transport phenomena will become possible over longer time intervals, lower velocities or greater distances. Dziedzina nauki engineering and technologymedical engineeringdiagnostic imagingmagnetic resonance imaging Program(-y) FP7-IDEAS-ERC - Specific programme: "Ideas" implementing the Seventh Framework Programme of the European Community for research, technological development and demonstration activities (2007 to 2013) Temat(-y) ERC-AG-PE4 - ERC Advanced Grant - Physical and Analytical Chemical sciences Zaproszenie do składania wniosków ERC-2013-ADG Zobacz inne projekty w ramach tego zaproszenia System finansowania ERC-AG - ERC Advanced Grant Instytucja przyjmująca ECOLE NORMALE SUPERIEURE Wkład UE € 2 500 000,00 Adres 45, RUE D'ULM 75230 Paris Francja Zobacz na mapie Region Ile-de-France Ile-de-France Paris Rodzaj działalności Higher or Secondary Education Establishments Kierownik naukowy Geoffrey Bodenhausen (Prof.) Kontakt administracyjny Damien Vogel (Mr.) Linki Kontakt z organizacją Opens in new window Strona internetowa Opens in new window Koszt całkowity Brak danych Beneficjenci (1) Sortuj alfabetycznie Sortuj według wkładu UE Rozwiń wszystko Zwiń wszystko ECOLE NORMALE SUPERIEURE Francja Wkład UE € 2 500 000,00 Adres 45, RUE D'ULM 75230 Paris Zobacz na mapie Region Ile-de-France Ile-de-France Paris Rodzaj działalności Higher or Secondary Education Establishments Kierownik naukowy Geoffrey Bodenhausen (Prof.) Kontakt administracyjny Damien Vogel (Mr.) Linki Kontakt z organizacją Opens in new window Strona internetowa Opens in new window Koszt całkowity Brak danych
