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Summary This paper presents preliminary results of a new T2Well version, coupled with modified ECO2M equation of state, able to simulate three-phase flow in the wellbore with the coexistence of liquid and gaseous CO2, with the final aim to be able to detect possible operational problems caused by phase changes during transient flow periods.

Paintings on canvas are complex structures created by superimposing layers of different composition. Investigations on the structure of these artworks can provide essential information on their state of conservation, pictorial technique, possible overpaintings, and in planning a proper conservation plan. Standard methods of investigation consist in sampling a limited number of fragments for stratigraphic analyses. Despite the recognized validity of these methods, they are affected by evident limitations. Nuclear magnetic resonance (NMR) profiling, often named NMR stratigraphy, is an NMR relaxometry technique applied by single-sided portable devices developed to overcome the disadvantages of microinvasive stratigraphic analyses. The potential of this approach on artworks, including wall paintings and a few examples of painted canvas, is described in the literature. In this study, NMR profiles of painting on canvas were examined by analyzing transverse relaxation time data by T2 quasi-continuous distributions and the results compared with standard stratigraphic cross-sections analysis. Combining signal intensity and T2 quasi-continuous distributions, the identification of textile, preparatory, and paint layers was enhanced. The diction "NMR stratigraphy" for these inhomogeneous layered artworks is also discussed. Indeed, unlike the stratigraphic cross-sections, NMR profiles provide information on a volume (flat slice), rather than on a surface, and the collected signal can derive from nonuniform and partially overlapping layers. This study paves the way for extensive investigations on relaxation time quasi-continuous distributions in various binder/pigment mixtures in order to improve the reliability of NMR profile as an innovative, non-invasive, and nondestructive method for analyzing paintings on canvas.

Geologists and Reservoir Engineers routinely use time-domain nuclear magnetic resonance (NMR) to learn about the porous structure of rocks that hold underground fluids. In particular, two-dimensional NMR (2DNMR) technique is now gaining importance in a wide variety of applications. Crucial issue in 2DNMR analysis are the speed, robustness and accuracy of the data inversion process. This paper proposes a multi-penalty method with locally adapted regularization parameters for fast and accurate inversion of 2DNMR data. The method solves an unconstrained optimization problem whose objective function contains a data-fitting term, a single L1 penalty parameter and a multiple parameter L2 penalty. We propose an adaptation of the Fast Iterative Shrinkage and Thresholding (FISTA) method to solve the multi-penalty minimization problem, and an automatic procedure to compute all the penalty parameters. This procedure generalizes the Uniform Penalty principle introduced in [Bortolotti et al., Inverse Problems, 33(1), 2016]. The proposed approach allows us to obtain accurate 2D relaxation time distributions while keeping short the computation time. Results of numerical experiments on synthetic and real data prove that the proposed method is efficient and effective in reconstructing the peaks and the flat regions that usually characterize 2DNMR relaxation time distributions.

Pathline or streamline computation is used today to improve the understanding of fluid flow behavior in groundwater modelling. In particular, pathline computation on unstructured grids requires an accurate velocity interpolation method when the flow velocity field is given by numerical simulators only at the faces of the grid blocks; as for example in the case of the Integral Finite Difference method is used for spatial discretization. In the case of 3D Voronoi unstructured grids, a corner velocity interpolation (CVI) method allows continuous velocity field interpolation while preserving the mass conservation principle. We have developed a computer code, named TOUGH2Path, able to compute the velocity field based on the CVI method and generalized barycentric coordinates for 3D Voronoi polytope grid blocks tailored for the TOUGH family of codes. Results for the classical quarter five spot problem show that the coded algorithm correctly reproduces the pathlines computed with semi-analytical methods.

Purpose: Reduced bone strength is associated with a loss of bone mass, usually evaluated by dual-energy X-ray absorptiometry, although it is known that the bone microstructure also affects the bone strength. Here, a method is proposed to measure (in laboratory) the bone volume-to-total volume ratio by single-sided NMR scanners, which is related to the microstructure of the trabecular bone. Methods: Three single-sided scanners were used on animal bone samples. These low-field, mobile, low-cost devices are able to detect the NMR signal, regardless of the sample sizes, without the use of ionizing radiations, with the further advantage of signal localization offered by their intrinsic magnetic field gradients. Results: The performance of the different single-sided scanners have been discussed. The results have been compared with bone volume-to-total volume ratio by micro CT and MRI, obtaining consistent values. Conclusions: Our results demonstrate the feasibility of the method for laboratory analyses, which are useful for measurements like porosity on bone specimens. This can be considered as the first step to develop an NMR method based on the use of a mobile single-sided device, for the diagnosis of osteoporosis, through the acquisition of the signal from the appendicular skeleton, allowing for low-cost, wide screening campaigns. © 2017 International Society for Magnetic Resonance in Medicine.

In this paper we present an improvement of the 2DUPEN algorithm (I2DUPEN) obtained by applying data windowing and Singular Value Decomposition (SVD) filtering. The presented I2DUPEN method solves a regularized weighted least squares problem where the weights are related to the statistics of the data. The SVD filtering is applied to reduce the problem size. The preliminary results on real 2D Nuclear Magnetic Resonance data show the potentiality of this strategy to improve the performance of the algorithm preserving reconstructions of good quality. Just as the original 2DUPEN algorithm, I2DUPEN can be used on a wide range of NMR data obtained from different kinds of samples, from multi-scale length porous materials to biological samples.

Fast-field-cycling nuclear magnetic resonance (FFC-NMR) is a powerful technique for non-destructively probing the properties of fluids contained within the pores of porous materials. FFC-NMR measures the spin&ndash, lattice relaxation rate R 1 ( f ) as a function of NMR frequency f over the kHz to MHz range. The shape and magnitude of the R 1 ( f ) dispersion curve is exquisitely sensitive to the relative motion of pairs of spins over time scales of picoseconds to microseconds. To extract information on the nano-scale dynamics of spins, it is necessary to identify a model that describes the relative motion of pairs of spins, to translate the model dynamics to a prediction of R 1 ( f ) and then to fit to the experimental dispersion. The principles underpinning one such model, the 3 &tau, model, are described here. We present a new fitting package using the 3 &tau, model, called 3TM, that allows users to achieve excellent fits to experimental relaxation rates over the full frequency range to yield five material properties and much additional derived information. 3TM is demonstrated on historic data for mortar and plaster paste samples.

How to estimate the risk of the occurrence of non-hydrocarbon components (nonHC) such as carbon dioxide (CO2), hydrogen sulfide (H2S) or nitrogen (N2), is one of the main issues in the field of petroleum exploration. Numerical models can provide valuable tools to predict the occurrence and distribution of such components. Different approaches exists to this end, starting from the simplest ones, relying onto geometrical considerations, up to those based on a fully physical description of the migration and accumulation processes.In this work, a procedure for efficient coupling of petroleum system analysis withmultiphase Darcy flow simulations is developed to obtain 3D time dependent representation of the migration paths and accumulation volumes of nonHC at basin scale on a geological timescale. We focus on the tests carried out to prove that is technically feasible to run simulations of very deep geological formations (high P, T, salinity) even if considering a very detailed picture of the transport phenomena (buoyant, viscous and capillary forces). The challenge is to find the right compromise between the needs to honor fine-scale hydrostratigraphic details of the structure and the size of the numerical model in its discretized form.

The inversion of two-dimensional NMR Relaxation data requires the solu- tion of a őrst-kind Fredholm Integral equation with separate exponential kernels. We extend to two-dimensions the Uniform Penalty principle (Borgia et al. J. Magn. Res- onance, 1998) by proposing an algorithm based on Tikhonov regularization with local regularization parameters and nonnegative constraints. The local regularization terms are computed as the ratio between noise norm and a combination of local curvature and gradient values. The corresponding regularization problem is solved by Projected Newton iterations. Experiments show better reconstructions of peaks and ŕat areas compared to Tikhonov regularization with global regularization parameter.

A new method is proposed for the diagnosis of osteoporosys by the use of a single-sided NMR device

Editorial of the Proceedings of the 12th International Bologna Conference on Magnetic Resonance in Porous Media (MRPM12), 9-13 February 2014, Victoria University of Wellington, Wellington, New Zealand

In fresh pork loin, the information concerning fat content is very important, both from the consumer as well as from the nutritional point of view. Knowing the fat content allows industry to classify the fresh loins accordingly. Fat content in loins is a factor related to moisture variability; therefore on-line, non-destructive technologies that could be used in an industrial environment to predict fat-to-moisture ratio are of special interest for companies from the pork processing sector. The time-domain nuclear magnetic resonance (1H TD-NMR), and in particular Relaxometry and Imaging (MRI), has been introduced as a promising alternative to traditional food characterization method due to its rapidity, simplicity, and potential for on-line non-destructive measurements. In this paper, the authors introduce original and innovative procedures using NMR Relaxometry and 1H nuclei imaging which can be employed to estimate the fat content in intact pork loins by exploiting the difference between fat and water longitudinal relaxation time (T1) distributions. They demonstrate how analysis of the quasi-continuous distributions of T1 in fresh intact loins allowed them to obtain a significant relationship between F/W ratios determined from Relaxometry and chemical analysis. This chapter also explains how both NMR Relaxometry and Imaging can estimate the fat-to-moisture ratios in loins in a non-destructive way.

The collection and composting of organic waste from both households and industries has long been recognized as a valuable contribution to waste management. The first step towards a “zero-waste” concept, in particular in the food processing sector, is the identification, quantification and characterization of residues. Thus considerable efforts have been focused towards the definition of compost maturity in order to decide on the quality of compost. Therefore the principal requirement of a compost for its safe use is a high degree of maturity, which implies a stable organic matter (OM) content and the absence of phytotoxic compounds and plant or animal pathogens. Magnetic Resonance Relaxometry (MRR) and Imaging (MRI) of hydrogen nuclei are optimal candidates to give information on the degree of degradation and maturity of compost, especially when there is needed a careful non-invasive and non-destructive characterization. Because many foods are proton-rich, e.g., from water, fat, carbohydrates, and proteins, MRR is a common tool to gain information about the composition and internal structure of foods, permitting also to monitor the compositional and structural modifications when they undergo natural or artificial processes. Since the relaxation times (longitudinal T1 and transverse T2) variations change the image contrast, MRI can easily monitor the structural changes in foods during processing and storage. MRI can detect and show internal variations in the water content, as well as changes in water interaction with cellular tissues. In this work typical MRR parameters as T1 and T2, and 1H signal amplitude were related to water content, and to micro and molecular structure of the compost itself, to follow the compost phases. Furthermore the authors used Quantitative Relaxation Tomography (QRT), a method to measure locally the relaxation times by means of MRI images. This technique allowed them to locally follow the FW biodegradation over time and to evaluate the maturity and quality parameters. In summary, matching magnetic resonance techniques with other standard analyses could be of great importance to fully describe the stages of composting and define the degree of compost maturity.

The inversion of two-dimensional Nuclear Magnetic Resonance (NMR) data requires the solution of a rst kind Fredholm integral equation with a two-dimensional tensor product kernel and lower bound constraints. For the solution of this ill-posed inverse problem, the recently presented 2DUPEN algorithm [V. Bortolotti et al., Inverse Problems , 33(1), 2016] uses multi- parameter Tikhonov regularization with automatic choice of the regularization parameters. In this work, I2DUPEN, an improved version of 2DUPEN that implements Mean Windowing and Singular Value Decomposition filters, is deeply tested. The reconstruction problem with filtered data is formulated as a compressed weighted least squares problem with multi-parameter Tikhonov regularization. Results on synthetic and real 2D NMR data are presented with the main purpose to deeper analyze the separate and combined e effects of these filtering techniques on the reconstructed 2D distribution.

Soil remediation has recently included the use of organic recycled materials (e.g. sewage sludge or paper mill sludge) which, thanks to their stability in aerobic conditions, can improve soil properties. Paper sludge, for example, adds nutrients to a poor Organic Matter (OM) soil, since the Total Organic Carbon (TOC) content is generally high. TOC and TOCto-Nitrogen ratio (TOC/N) and other chemical elements (P, Ca,Mg, Na and K) are generally used to characterize amended soils [1]. It has been recently observed that the quantity of OM can influence soil texture and consequently the pore size distribution. New efforts are arising towards the use of non-invasive and non-destructive techniques to characterize this kind of sample, to gain more reliable information on interactions between OM and soil mineral phases. Proton Time-Domain Nuclear Magnetic Resonance (1H TD-NMR) can be profitably employed to investigate the textural properties of these amended environmental substances. Applications of the TD-NMR technique are not so much used in soil science, although it shows great potential, probably due to the huge heterogeneity of these materials and to the presence of high paramagnetic ion concentrations found both in natural soils and in the contaminants. In particular, in this study contaminated soils have been characterized by T1 distribution analysis, using a specifically developed NMR sequence to overcome experimental difficulties, to obtain information on the porosity related to the irreducible water [1]. On the other side, N2 sorption at soils surfaces has been usually used for the determination of the Specific Surface Area (SSA). SSA depends on the structure of soil aggregates and permits one to investigate OM-soil minerals aggregation [2]. In this work we investigate how the amount of TOC in soil sample can be investigated by TD-NMR and SSA techniques. [1] M. Vannini, A. Bonoli, V. Bortolotti, P. Macini, E. Mesini. Proceedings of the 3rd International Conference on industrial and hazardous waste management, Chania (Crete), September 2012. [2] R. Wagai, L. Mayer, K. Kitayama, Geoderma, 149 (1-2), 152-160, (2009).

In order to well distinguish different tissues of the human body, it is of paramount importance to find procedures and sequences that improve the contrast of Magnetic Resonance Imaging (MRI) images. In particular, the possibility to image only specific parts of organs and/or tissues while ignoring all the others is a very valuable feature. A way to address this problem is to develop dedicated MRI sequences able to filter the 1H nuclei signals on the basis of the different longitudinal relaxation times (T1) of the tissues and to produce images where components are suppressed. Instead of using standard signal selection/attenuation sequences, such as the Short Time Inversion Recovery and Multiple Inversion Recovery, whose effects are to zero the signal for a discrete number of T1 values, we developed the Parametrically Enabled Relaxation Filters with Double and multiple Inversion (PERFIDI) filter sequences. These sequences acting on a range of T1 behave as electronic band-pass, high-pass and low-pass filters, primarily focused on the components which pass through, rather than on those blocked. We tested PERFIDI filter sequences on a synthetic two-component test tube sample. Preliminary applications on biological tissues have shown that this technique can effectively work on a range of T1 values.

The collection and composting of organic waste both from families and from industrial production processes are considered as good practices for waste management. Composts made from sewage sludge, household waste, straw, bark, have successfully been employed in gardens, pot cultures, arable land, and even in forests. In general, composts contribute to the structure and nutrient supply of soils or artificial substrates for plant growth. Compost chemical and microbial properties, which define compost maturity, are important key factors for correct use in environmental and agricultural activities. Parameters such as the temperature, pH and C/N ratio can be observed to monitor the compost maturation and to decide on the compost quality and stability [1]. Proton Nuclear Magnetic Resonance relaxometry (1H-NMR) can be used to follow compost biodegradation during time, as it permits the monitoring of internal compositional and structural modifications, as already observed in many food types when they experience natural or not natural processes [2]. Since generally the parameters of biodegradation are volume averaged and little is known on the influence of local behaviour on the final overall biodegradation, a local investigation of the compost mixture is desirable [3]. Quantitative Relaxation Tomography (QRT), which gives spatial information on relaxation times combining 1H-NMR relaxometry with Magnetic Resonance Imaging, can be an innovative tool to monitor compost degradation and maturation. In this work a sample of compost has been monitored for two months by means of both T1 and T2 QRT maps [4]. In a first preliminary analysis, both kinds of maps seem to well describe a trend that follows the three phases of the composting process: mesophilic, thermophilic and maturation, moreover having information of the spatial distributions of these phases. [1] J. Forster, W. Zech, E. Wiirdinger, Biology and Fertility of soils, 16, 93-99, (1993). [2] M. F. Marcone, S. Wang, W. Albabish, S. Nie, D. Somnarain, A. Hill, Food Research International, 51(2), 729-747, (2013). [3] F. P. Duval, S. Quellec, A. Trémier, C. Druilhe, F. Mariette, Waste management, 30(4), 610-619, (2010). [4] G. C. Borgia, V. Bortolotti, P. Fantazzini, journal of Applied Physiscs, 90(3), 1155-1563, (2001).

The internal distribution of water-repellent products applied to surfaces to make a porous material repellent is of great interest in the field of the safeguard of cultural heritage items such as stone buildings, statues and frescos. Water is the main cause of degradation of porous materials exposed to rain, moisture and air pollutants. In previous papers[1], it has been shown how MRI allows one to evaluate and compare the performance of products and treatments used. Those products were commercial ones, made for different uses than cultural heritage items protection. In the middle of the ‘80s, the group of CNR in Florence started to synthesize mono-biand tetra-functionalized perfluoropolyetheric compounds for the specific use in the protection of stone, with the following properties: (i) stable to chemical agents, heating and UV irradiation; (ii) high water-repellency; (iii) ability to perform treatments in such a way that the natural permeability of stone to air and water vapor is not significantly reduced; (iiii) chemically inert with the stone substrate, and therefore completely reversible. Unfortunately, the best products synthesized were soluble in Chlorofluorocarbons. Now, new products containing a perfluoropolyetheric and hydro-alcoholic solvents, but not soluble in water or Chlorofluorocarbons. Their hydrophobic and penetration properties have been investigated by MRI images, taken on biocalcarenite samples treated with commercial and new fluorinated compounds, at increasing times during capillary water absorption. The presence of water inside each sample could be visualized and the height reached by the wetting front quantified as a function of time. The images were analyzed by an in-house software able to identify the front by an objective criterion. The images show the different protection efficiency of products and treatments. Good fits to the data were obtained with theoretical and empirical models of absorption kinetics, starting from the Washburn model. The data analysis gives us parameters useful to quantify the effects of the treatments on the capillary properties. The results demonstrate the better performance of the new fluorinated compounds able to preserve stones and environment. [1] M. Gombia et al., J Appl Phys, 103, 094913 (2008).

Immagini MRI di sezioni interne di materiali porosi consentono di valutare l’efficacia di prodotti e trattamenti protettivi al fine di ottimizzare protocolli di intervento. Sono stati sintetizzati prodotti contenenti blocchi perfluoropolieterei, solubili in alcol e in solventi idroalcolici, ma non in CFC. Mediante MRI quantitativa ed un software sviluppato ad hoc é stato possibile determinare l’altezza del fronte di imbibizione dell’acqua in campioni di biocalcarenite trattati con questi prodotti e con altri commerciali. Sono stati ottenuti buoni fit dei dati a modelli ottenuti partendo dal modello di Washburn [1]. I risultati dimostrano la migliore efficacia dei nuovi prodotti, non dannosi per l’ambiente. [1] M. Gombia, V. Bortolotti, R.J.S. Brown, M. Camaiti, P. Fantazzini J Appl Phys 103 (2008) 094913.

Fat suppression in Magnetic Resonance Imaging (MRI) images is an important diagnostic topic. In this work, through NMR Relaxometry and Imaging of 1H nuclei we estimated the Fat/Water (F/W) ratio on pig loins, assumed as model of human muscle tissue, by analyzing 1H longitudinal relaxation times (T1) distributions and quantitative MRI images. It is known that water and fat proton signals in tissues have different T1 values. The innovative characteristic of our approach is to assume that T1 values follow a quasi-continuous distribution, instead of a discrete distribution. F/W ratios of the samples were determined through NMR Relaxometry by distinguishing the signal of fat 1H nuclei from that of the water through the choice of a proper cut-off on the T1 distributions. F/W ratio was determined on MRI images acquired with the “classic” Short Time Inversion Recovery sequence. Innovative Parametrically Enabled Relaxation Filters with Double and multiple Inversion (PERFIDI) sequences, that implement band-pass filters, were also used. The correlation between NMR and an independent destructive chemical analysis performed on the same samples gave very good results for both Relaxometry and Imaging techniques.

Soil remediation has recently included the use of organic recycled materials (e.g. sewage sludge or paper mill sludge) which, thanks to their stability in aerobic conditions, can improve soil properties. Paper sludge, for example, add nutrients to a poor Organic Matter (OM) soil, since their Total Organic Carbon (TOC) content is generally high. TOC and TOC to Nitrogen ratio (TOC/N) and other chemical elements (P, Ca, Mg, Na and K) are generally used to characterize amended soils. It has been recently observed that the quantity of OM can influence soil texture and consequently the pores size distribution. Therefore, techniques such as the non-invasive and non-destructive Time-Domain Nuclear Magnetic Resonance of nuclei 1H in (1H TD-NMR) and N2 adsorption/desorption can be profitably employed to investigate the textural properties of these amended environments. The 1H TD-NMR signal is proportional to the total amount of water inside the pores and gives information on the pore arrangement, by means the relaxation times (longitudinal T1 and transversal T2) distributions. In this study contaminated soils have been characterized by T1 distributions analysis, using a specifically developed NMR sequence that overcomes many measurement difficulties due to the complex structure of OM and the presence of paramagnetic elements. N2 sorption at soils surfaces allows the determination of the specific surface area (SSA), which consents the characterization of much larger volume or mass samples than microscopic techniques. The SSA depends on the structure of soils aggregates and permits to model OM-soil minerals aggregation. In this work we show how the increasing amount of TOC, which influences pores structure, can be investigated in a complementary way by both techniques.

La tecnica di Rilassometria a Risonanza Magnetica Nucleare (MRR) rappresenta per le scienze ambientali un nuovo strumento di caratterizzazione non invasivo dei suoli naturali e contaminati, mentre in ambito petrofisico è da tempo utilizzata per avere informazioni dettagliate sulla struttura delle rocce e sulle interazioni delle loro fasi fluide. La caratterizzazione NMR di mezzi porosi è correlata alla conoscenza del parametro di relassivitá superficiale (ρ), a sua volta fortemente influenzata dalla presenza di sostanze paramagnetiche, spesso abbondanti nei suoli. Nota ρ, la misura dei parametri MRR (tempi di rilassamento) consente quindi la determinazione della distribuzione delle classi di pori. Questa relazione oltre a proporre un sommario delle tecniche attualmente utilizzate per la determinazione della relassivitá superficiale in ambito petrofisico riporta i risultati dell’applicazione di una di queste tecniche a un campione di suolo utilizzato in operazioni di bonifica ambientale.

In the numerical simulation of the geothermal reservoir behaviour and of its exploitation, the domain discretization is one of the factors affecting the delta between predicted and measured values. Increasing the grid resolution of the numerical model around the volumes of interest can reduce the above mentioned delta, but that requires computational and operating costs whose entity depends on the complexity of the model. The simulation of 3D models characterized by a huge number of blocks produces a large amount of data that are difficult to analyze without adequate post-processing and visualization tools. The difficulties increase when we adopt unstructured grids (Voronoi) and local refinement in spatial discretization. In order to enhance spatial discretization and data management, a pre-processor (TOUGH2GIS) has been developed using GRASS GIS (Geographical Information System [1]) and AMESH [2] open source codes. This new pre-processor significantly reduces operating errors, the time required by pre-processing activities and locally refined unstructured grids generation and its update. Thanks to GIS approach, conceptual model elaboration and its conversion into a numerical model have been integrated under a software (TOUGH2GIS) so that updates and changes to the conceptual and numerical models can be made quickly. TOUGH2GIS is a suite of tools (BASH scripts and C codes with tcl-tk graphical user interface) for automating several operations such as domain discretization, rock types assignment, mesh file generation, simulation's output import and link to the numerical model as database attribute tables. In a few words, TOUGH2GIS represents an efficient tool supporting the whole operations required by model calibration. TOUGH2Viewer is a post-processor (written in Java, developed in NetBeans 7.1 environment and mainly based on Java3D libraries) that allows a three dimensional graphic reconstruction of the numerical model and let the user to explore, through a simple and intuitive graphical interface, the output of TOUGH2. Originally thought for unstructured grids visualization, the post-processor can also manage structured grids created with the MESHMAKER module. In particular, the software handles the visualization of 3D grid (structured and unstructured), 3D vector representation of mass and heat transfer, isosurfaces of the simulated variables, 2D contour maps. It is possible to browse simulated model data in a 3D view through rotation, pan, zoom, horizontal and vertical sections. The user can display the variables simulated or the rock types assigned to the nodes of the grid in colour scale. Moreover, the user can import isosurfaces in shape file format and view them along with the 3D model. Finally, the user can get space and time profiles of the thermophysical properties present in the output file by selecting the node or column of interest. The 3D visualization of the mass and heat transfer between adiacent grid nodes is obtained as vector sum of the flows in input / output to the node. All display functions can be customized through a simple and intuitive graphical interface, in order to optimize simulation analysis and to produce high quality printouts. The performances of TOUGH2GIS and TOUGH2Viewer have been tested executing history matching and developing exploitation scenarios for a Tuscan high enthalpy geothermal field. [1] http:// grass.fbk.eu [2] http://esd.lbl.gov/research/projects/tough/licensing/free.html

Proton Time Domain Nuclear Magnetic Resonance (1H TD-NMR) is a powerful non-invasive and non-destructive technique widely used in many fields to investigate porous media saturated with water. However, 1H TD-NMR is not so much used in soil science, especially on samples rich in organic content. In this study the correlation of the longitudinal relaxation times to the total organic carbon content of materials used in remediation treatment (in particular, mixtures of paper mill sludges and natural soils) has been investigated. In these samples it has been observed a correlation between the increase of carbon content and the decrease of detected water in the micropores. This result corroborates the idea that organic matter tends to migrate inside the micropores, leaving less space available for water.

L’applicazione delle tecniche a Risonanza Magnetica Nucleare (NMR), in particolare la Rilassometria NMR (MRR), rappresentano un nuovo terreno di ricerca nell’ambito delle scienze ambientali, in particolare come strumento di caratterizzazione non invasiva. Con queste metodologie ci si propone di caratterizzare campioni di suolo naturale miscelati con fanghi di cartiera. Come ampiamente mostrato in altri ambiti, dove viene da tempo utilizzata, questa tecnica fornisce informazioni dettagliate sulla struttura dei campioni e sulle interazioni delle sue fasi. In questa ricerca i parametri MRR (distribuzione dei tempi di rilassamento) hanno permesso la determinazione di alcune caratteristiche petrofisiche fondamentali (quali la distribuzione delle classi di pori e l’acqua irriducibile) di queste miscele, tenendo conto delle notevoli difficoltà, date dalla complessa composizione chimica, che presenta questa tipologia di campioni.

The paper is addressed to help designing alkali/surfactant flooding Enhanced Oil Recovery methods. In particular, it has been verified that a polar interaction mechanism to change wettability of a carbonate rock from water-wet to oil-wet can be obtained by injecting adequate chemicals, and in particular a solution of oleic acid and non-polar oil, like dodecane used for laboratory experiments. It is worth recalling that wettability is a petrophysical property that directly affects oil recovery by controlling the location, flow and distribution of fluids inside the reservoir rock. The study has been performed by combining spatially resolved and spatially non-resolved 1H-NMR (Nuclear Magnetic Resonance) information obtained on full-size cores (up to 7cm in diameter). In particular, spatially resolved quantitative NMR imaging maps (or Quantitative Relaxation Tomography, QRT) and spatially-non resolved (or Magnetic Resonance Relaxometry, MRR) analyses have been performed on full-size cores to track the process and to assess the quality of wettability reversal. Changes of relaxation time distributions and of T1 maps obtained in the experiments seem correlated with wettability changes measured after the chemical treatment, i.e., the contamination with a solution of oleic acid and dodecane. Although further investigations are needed, the combination of MRR and QRT seems a promising technique to correlate the traditional Amott wettability index with local values of T1 in internal sections of a rock sample. In particular, the paper deals with the assessment and monitoring of wettability reversal of carbonate rocks used in laboratory studies to evaluate the efficiency of chemical Enhanced Oil Recovery methods, and in particular of alkali/surfactant flooding. The combination of 1H-NMR relaxation analysis, characterized by high temporal resolution, with quantitative maps, characterized by high spatial resolution, permits a better knowledge and the monitoring of the processes occurring inside the pore space leading to wettability reversal.

Vengono messe a confronto due tecniche, la Risonanza Magnetica (MRI) e la tomografia assiale computerizzata (TAC), per ottenere informazioni quantitative sulla cinetica di assorbimento dell’acqua in sezioni interne di materiali lapidei. Entrambe le tecniche permettono di studiare adeguatamente il fenomeno. Nel caso in cui si formi un fronte di bagnamento, come per la Pietra di Lecce, l’analisi delle immagini consente di determinare in modo quantitativo l’altezza di risalita in funzione del tempo ed i dati possono essere interpretati alla luce del modello di Washburn per l’assorbimento capillare. Nel caso in cui il fronte non si formi, come per campioni di biocalcareite provenienti da una cava presso la Valle dei Templi di Agrigento, il fenomeno può essere descritto mediante metodi stocastici.

Il sempre crescente interesse verso i Beni Culturali suscita molteplici problematiche inerenti la salvaguardia e la diagnosi del loro stato di conservazione. In questo ambito, lo studio delle caratteristiche, quali ad esempio le proprietà capillari delle rocce sedimentarie, ricopre un’importanza cruciale non solo per studiare lo stato di conservazione ma anche per fornire utili indicazioni sulle possibili tecniche e sui materiali da utilizzare negli eventuali trattamenti di protezione e restauro. Al fine di ottenere approfondite informazioni sulle proprietà capillari, il presente lavoro propone un metodo matematico utile nello studio della cinetica di assorbimento capillare. Lo studio è stato condotto su una roccia sedimentaria particolarmente omogenea, la Pietra di Lecce, analizzando le immagini del campione, acquisite mediante la tecnica di imaging NMR (Nuclear Magnetic Resonance, MRI). Il rumore presente nelle immagini è stato ridotto grazie all’utilizzo delle trasformate wavelet. Le immagini elaborate e ricostruite tramite un algoritmo che implementa la trasformata DWT (Discrete Wavelet Transform) – epsilon-decimata, forniscono utili informazioni per la caratterizzazione della cinetica di assorbimento dell’acqua.

Magnetic resonance imaging (MRI) is a powerful technique to study capillary water absorption kinetics in sedimentary rocks. However, the noise in the images can limit the correct identification and the quantitative measurement of the average height reached by the wetting front inside the porous material where imbibition occurs. Therefore, denoising methods can be applied to improve the image quality for a more accurate analysis, without the disadvantages of longer acquisition times. This study attempts to improve the signal-to-noise ratio of the images acquired by MRI on a sedimentary rock (Pietra di Lecce) using a waveletbased thresholding technique. The idea is to average some slightly different discrete wavelet tansforms (DWT), called e-decimated DWT, to define the stationary wavelet transforms (SWT).

L'efficacia dei trattamenti normalmente impiegati per proteggere e/o consolidare materiali lapidei può essere valutata mediante la tecnica di imaging a risonanza magnetica nucleare (MRI), che consente di studiare in modo quantitativo, non invasivo, non distruttivo, la cinetica di assorbimento capillare dell'acqua. In campioni omogenei (Pietra di Lecce) si forma un fronte piatto (con una discontinuità netta alla scala di misura) e la tecnica MRI permette di seguire la cinetica in quanto consente di misurare, in funzione del tempo, l'altezza raggiunta da tale fronte in qualunque sezione interna del campione. Vengono confrontati i risultati ottenuti sullo stesso litotipo utilizzando due diversi prodotti idrorepellenti. i risultati vengono interpretati alla luce del modello di washburn per l'assorbimento capillare, fornendo parametri utilizzabili per quantificare l'efficacia del trattamento.

In questo capitolo viene descritta l'evoluzione stratigrafica della prozione finale della deposizione epiligure, sino al passaggio ai sedimenti quaternari del fronte appenninico-padano. La successione stratigrafica è controllata dagli eventi tettonici appenninici e da fattori regionali eustatici, come nel caso della crisi di salinità messiniana.

Questo capitolo evidenzia gli aspetti strutturali dellAppennino bolognese, con particolare riguardo all'assetto strutturale delle unità liguri, della geometria e messa in posto della coltre ligure e dell'attività tettonica più recente, in collegamento con l'evoluzione della Pianura Padana.

none 8 si The bone volume fraction, defined as the Bone-Volume-To-Total-Volume ratio (BV/TV), is an important parameter in the assessment of the bone micro-structure, and is related to the fracture risk in osteoporosis. Although Magnetic Resonance Imaging (MRI) can assess bone micro-architecture parameters in-vivo, high-field whole body MRI scanners are hardly suitable for widescale screening campaigns. Recently, a new NMR application to assess in laboratory the BV/TV of trabecular bone (TB) has been proposed using low-field single-sided NMR. This paper presents an improvement of this technique that allows detection of only the signal from the marrow in the TB suppressing signals from other tissues, which may be present in the sensitive volume of singlesided scanners in a real scenario. The improvement was achieved by filtering signal acquisition by molecular diffusion. Experiments based on an ad-hoc designed Diffusion Weighted T1-T2 pulse sequence have demonstrated that muscle and cartilage signals can be suppressed by using diffusion weighting. On the basis of those experiments, a 1D measurement was established to allow correct estimation of the BV/TV of a TB sample also in the presence of muscle tissue in the sensitive volume of the NMRscanner. The experiments presented, carried out with the NMR-MOUSE PM10 and the NMR-MOLE, exploiting diffusion-weighted pulse sequences, may pave the way for the in-vivo BV/TV evaluation using single-sided scanners. mixed Barbieri, M.; Brizi, L.; Bortolotti, V.; Fantazzini, P.; Nogueira d’Eurydice, M.; Obruchkov, S.; Liu, H.; Galvosas, P. Barbieri, M.; Brizi, L.; Bortolotti, V.; Fantazzini, P.; Nogueira d’Eurydice, M.; Obruchkov, S.; Liu, H.; Galvosas, P.