1,721,306 research outputs found
Stone Porosity, wettability changes and other features detected by MRI and NMR relaxometry: a more than 15-year study
No full textScientists applying magnetic resonance techniques to cultural heritage are now a quite vast and international community,
even if these applications are not yet well known outside this community. Not only laboratory experiments but also
measurements in the field are now possible, with the use of portable nuclear magnetic resonance (NMR) instruments
that enable non-invasive and non-destructive studies on items of any size, of high artistic and historical value as well
as diagnosis of their conservation state. The situation was completely different in the second half of the 1990s when
our group started working on applications of NMR to cultural heritage, by combining the knowledge of NMR for fluids
in porous media at the University of Bologna, with the skilfulness of the chemists for cultural heritage of CNR and
University of Florence, and Safeguarding Cultural Heritage Department of Aosta. Since then, our interest has been mainly
devoted to develop methods to study the structure of pore space and their changes as a result of the decay, as well as to
evaluate performance of the protective and conservative treatments of porous materials like stone, ceramic, cements and
wood. In this paper, we will review the pathway that led us from the first tentative experiments, in the second half of the
1990s to the current work on these topics
13th International Bologna Conference on Magnetic Resonance in Porous Media - Bologna 2016: Conference Handbook and Book of Abstract
Full text linkWelcome to Bologna MRPM13, the 13th International Bologna Conference on Magnetic Resonance in Porous Media, an AMPERE Event organized under the auspices of Alma Mater Studiorum, University of Bologna. The Conference will be held at the University’s prestigious School of Engineering and Architecture, which has made available its excellent facilities.
The conference series was founded by the University of Bologna, where the first meeting was held in 1990. MRPM2, held in 1993, was hosted by the University of Kent, Canterbury, UK, MRPM3 in 1995 at the Université Catholique of Louvain-la-Neuve, Belgium, and MRPM4, in 1997, in Trondheim, Norway. The conference returned to Bologna for its fifth edition in
2000. MRPM6 was organized in 2002 at the University of Ulm, Germany, and MRPM7 in 2004 in Palaiseau, France. After MRPM7, the community joined the Groupement Ampere as the MRPM Division, and the Conferences, now called the “Bologna MRPM Conferences,” became Ampere Events. MRPM8 returned to Bologna in 2006; MRPM9 in 2008 was hosted
by the Schlumberger Research Center (Cambridge, MA, USA); MRPM10 in 2010 at the University of Leipzig, Germany; MRPM11 in 2012 at the University of Surrey (Guildford, UK); and MPM12 in 2014 at the University of Wellington, NZ. MRPM Conference Proceedings were initially published as special issues of Magnetic Resonance Imaging (MRPM1 to
MRPM8) while MRPM9 and MRPM10 came out as part of the AIP Conference Proceedings Series. Since MRPM11, proceedings have been published as special issues of Microporous and Mesoporous Materials. In addition, since MRPM8 (2006), poster presenters may submit papers based on their posters for inclusion in special issues of the open-access on-line
journal Diffusion Fundamentals. As was the practice at previous conferences, all authors of the Invited and Oral communications are invited to prepare a manuscript for inclusion in the MRPM13 Proceedings. After review, contributions will be published in a special issue of Microporous and Mesoporous Materials. The manuscripts should be no more than four printed pages and comply precisely with the Journal’s editorial indications. MRPM conferences look at progress achieved by magnetic resonance in furthering understanding porous media and fluids inside the pore-space. The meetings are also intended to encourage contact among people from different academic and industrial backgrounds. Researchers in Physics, Chemistry, Engineering, Life Sciences, Mathematics, Computer Sciences, and Industrial Applications will benefit from the exchange of ideas, experiences and new approaches. Topics of MRPM13 will include innovative techniques to study structures, the behavior of fluids and their interactions in a wide range of natural and artificial materials, including rocks, cements, biological tissues, foodstuffs, wood, particle packs, sediments, pharmaceuticals, zeolites, and bioconstructs. Advances in hardware, methodology, data acquisition and processing are also on the agenda for
discussion.
The Giulio Cesare Borgia Prize for Young Researchers will be awarded at the end of the Conference. The Prize (three thousand Euro offered by our DICAM and DIFA Departments, University Bologna) was established in “memory of the contribution made by Giulio Cesare Borgia to the development of Magnetic Resonance in Porous Media and for the particular attention he always paid to the enthusiasm, passion, and courage of young people who undertook the difficult and adventurous path of scientific investigation in this fascinating area of research”. The award will be resented to an emerging (usually under 35 year old) scientist whose presentation at the Conference shows greatest promise for future scientific leadership. Contributions to the Conference are as follows: Invited speeches (20 minutes + 5 minute discussion), Oral presentations (12 minutes + 3 minute discussion), and Poster presentations during the Poster Session. Posters will be
numbered; the numbered poster list is printed in the Scientific Programme.
The Organizing Committee would like to thank all sponsors and donors for their support. These include: Università di Bologna (IT); Dipartimento di Fisica e Astronomia (DIFA, U. Bologna, IT); Dipartimento DICAM (U. Bologna, IT); Scuola di Ingegneria e Architettura (U. Bologna, IT); Stelar s.r.l. (IT); Bruker Biospin GmbH (DE, IT); Niumag (China); Oxford Instruments (UK); MR Solutions (UK); Pure Devices GmbH (DE); Jeol S.p.A. (IT); Lab-Tools Ltd (UK). The Organizing Committee is also very grateful to Prof. Ezio Mesini, President of the School of Engineering and Architecture, for making available the conference venue at the School, and to Professors Ezio Mesini and Ferruccio Trifirò, President of the Accademia dell’Istituto delle Scienze di Bologna, for hosting the NMR School in the Academy's Ulisse Hall.
On behalf of the Organizing Committee, I wish you an enjoyable and fruitful time in Bologna.
August 21st 2016 Villiam Bortolotti Chair, Bologna MRPM13
DICAM, University of Bologn
Quantitative Nuclear Magnetic Resonance Imaging, Profiling and Diffusometry on Fluorinated Compounds to Preserve Cultural Heritage Porous Media and Safe for the Environment
No full textThis work was focused on the preparation of a new protective agent with low average
molecular weight containing short pendant perfluoropolyether segments linked to an
oligosuccinamide chain in order to achieve: (i) high hydrophobic effect and photo-stability, (ii)
good adhesion to the rock through the polar amidic groups, (iii) excellent distribution on the pore
walls surface without their blockage, (iv) solubility in environmental friendly solvents.
Hydrophobic penetration and distribution properties of the compound applied on a
biocalcarenite (Lecce stone), have been investigated by Nuclear Magnetic Resonance (NMR)
Imaging, Profiling and Diffusometry of 1H nuclei, and compared with a perfluorinated commercial
product. These NMR techniques has been proved to be a valid non-destructive and non-invasive
technique for monitoring the conservation state and water absorption in materials and objects of
interest to cultural heritage, as well as for evaluating the efficiency and distribution of protective or
consolidation treatments
Profiling e Diffusometry NMR di materiali porosi: dalle applicazioni per la protezione e conservazione di Beni Culturali alla caratterizzazione del tessuto osseo
No full textLa strumentazione NMR single-sided permette di realizzare Profiling e Diffusometry dell’interno di materiali porosi saturati con fluidi idrogenati, solitamente acqua. Dal segnale NMR acquisito in profondità si possono determinare localmente il contenuto di acqua e proprietà dello spazio poroso (porosità, distribuzione dimensioni dei pori, rapporto superficie/volume, tortuosità). Partendo dalle applicazioni per i Beni Culturali, si mostrerà come tali tecniche possano essere trasferite con successo anche al tessuto osseo trabecolare, aprendo la strada verso una nuova tecnica diagnostica dell’osteoporosi. Progetti finanziati (per i Beni Culturali) dal Centro Fermi (Roma) e (per il tessuto osseo) dalla Fondazione del Monte (Bologna e Ravenna)
Pore-size evaluation by single-sided nuclear magnetic resonance measurements: compensation of water self-diffusion effect on trasverse relaxation
No full textWater compartmentalization, cell viability and morphology changes monitored under stress by 1H-NMR relaxometry and phase contrast optical microscopy
No full textThe quasi-continuous distributions of spin-lattice (T1) and spin-spin (T2) relaxation times of a population of cells kept under stress conditions for about 400 h has been obtained by 1H-NMR relaxometry. The comparison with the results obtained from the analysis of cell viability and morphological variations by phase contrast optical microscopy and performed with acquisition times, duration and conditions matching those of the relaxometry experiments allowed us to identify three main phases of the processes related to the exchanges of water and remodeling of cellular compartments: between 0 and 40 h the intra- and extra-cellular compartments are characterized by a T2 of ~250 ms and of ~2 s respectively and the cell population halflife has been experimentally evaluated to be ~45 h; after 40 and until 100 h cells NMR parameter changes suggest that the confined water is increasing according to the progressive fragmentation of the cells membrane; over 100 h almost all cells are non-viable and the constancy of the main NMR parameters reflects the reaching of the final equilibrium of the system. In conclusion our observations validated the use of NMR as a non-destructive, noninvasive powerful technique for monitoring the progression of cellular processes involving
compartments water exchange and reorganization
Nano and Sub-nano multiscale porosity formation and other features revealed by 1H NMR relaxometry during cement hydration
No full textCement hydration occurs when water is added to cement powder, leading to the formation of crystalline products like Portlandite and the quasi-amorphous, poorly crystalline, calcium silicate hydrate (C-S-H) gel. Despite its importance in determining the final properties of the cement, many models exist for the nano and sub-nano level organization of this liquid stone. H-1 NMR relaxometry in White Portland Cement paste during hydration allowed us to monitor the formation and evolution of the multiscale porosity of the cement, with the formation of structures at nano and sub-nano levels of C-S-H gel (calcium silicate interlayer water, water in small and large gel pores) along with three low-mobility H-1 pools, identified as H-1 nuclei in C-S-H layers, likely belonging to OH groups, with H-1 nuclei in Portlandite, and in crystal water of Ettringite. By assuming these assignments, our data allowed us to compute the distances of pairs of H-1 nuclei in Portlandite and in crystal water ((1.9 +/- 0.2) angstrom and (1.6 +/- 0.1)angstrom, respectively), consistent with the known values of these distances. The picture of the porous structure at nano and sub-nano levels emerging from our results is consistent with the Jennings colloidal model for C-S-H gel. Moreover, the constant values observed during hydration of parameters extracted from our data analysis strongly support that model, being compatible with the picture of C-S-H gel developing in comparable-sized clumps of the same composition, but not easily interpretable by models proposing quasi continuous sheets of C-S-H layers
Two 1H-NMR methods to measure internal porosity of bone trabeculae: by solid-liquid signal separation and by longitudinal relaxation
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