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Advanced and Integrated Petrophysical Characterization for CO2 Storage: Application to the Ketzin Site — Reservoir simulations and monitoring of CO2 storage require specific petrophysical data. We show a workflow that can be applied to saline aquifers and caprocks in order to provide the minimum data set for realistic estimations of storage potential and perform pertinent simulations of CO2 injection. The presented series of experiments are fully integrated with quantitative log data analysis to estimate porosity, irreducible saturation, drainage capillary pressure and water relative permeability, residual gas saturation, resistivity-saturation relationships and caprock transport properties (permeability and diffusivity). The case considered is a saline aquifer of the Triassic Stuttgart formation studied in the framework of the CO2SINK onshore research storage, the first in situ testing site of CO2 injection in Germany located near the city of Ketzin. We used petrophysical methods that can provide the required data in a reasonable amount of time while still being representative of the in situ injection process. For two phase transport properties, we used the centrifuge technique. For resistivity measurements, we used the Fast Resistivity Index Measurement (FRIM) method in drainage and imbibition, at ambient and storage conditions. For caprock characterization, we used a fast NMR (Nuclear Magnetic Resonance) deuterium tracer technique to measure diffusivity and a modified steady state innovative technique to determine permeability. Entry pressure has also been evaluated using several methods. Resistivity and NMR logs were analyzed to provide a continuous estimation of irreducible saturation for the entire storage zone and to judge on the representativity of the samples analyzed in the laboratory. For the Ketzin site, the storage zone is a clayey sandstone of fluvial origin locally highly cemented, with porosity around 30% and permeability ranging from 100 to 300 mD. Two zones were identified on the logs characterized by two different irreducible saturation ranging from 15 up to 35%. The measured relative permeability curves show a sharp decrease of the water effective permeability and suggest that a saturation lower than 50% cannot be reached in practice. The exponent of the resistivity index curve is about 1.7, lower than the default value of 2. The caprock has a permeability of 27 nD, a porosity around 15% and a pore diffusivity of 0.8 x 10-9 m2/s La simulation et le suivi d’un stockage de CO2 requiert des données pétrophysiques spécifiques. Nous présentons un ensemble d’expériences applicables à tout stockage et à toute couverture, fournissant des données pour des simulations numériques réalistes du potentiel de stockage et de l’injection. Ces expériences sont intégrées avec les données diagraphiques pour l’estimation de la porosité, la saturation irréductible, la pression capillaire et la perméabilité relative de l’eau en drainage, la saturation en gaz résiduelle, les relations résistivité-saturation et les propriétés de transport de la couverture (perméabilité et diffusivité). Le cas considéré est l’aquifère salin du Trias dans le contexte du projet CO2SINK, le premier site expérimental de stockage en Allemagne situé près de Ketzin. Nous avons utilisé des méthodes de mesure nécessitant des durées raisonnables tout en restant représentatives des processus in situ. Pour le transport diphasique, nous avons utilisé la centrifugation. Pour la résistivité, nous avons utilisé une méthode rapide « Fast Resistivity Index Measurement » (FRIM) en drainage et imbibition, en condition ambiante et en condition de stockage. Pour la caractérisation de la couverture, nous avons utilisé une technique rapide RMN (Résonance Magnétique Nucléaire) utilisant le deutérium comme traceur pour la mesure de diffusion et une méthode stationnaire innovante pour la mesure de perméabilité. La pression d’entrée a également été évaluée. Les diagraphies RMN et de résistivité ont également été utilisées pour estimer de manière continue la saturation irréductible et juger de la représentativité des échantillons analysés au laboratoire. Pour le site de Ketzin, la zone de stockage est un grès argileux d’origine fluviatile localement très cimenté d’une porosité d’environ 30 % et d’une perméabilité variant de 100 à 300 mD. Deux zones se distinguent par des saturations irréductibles variant de 15 à 35 %. La courbe de perméabilité relative à l’eau présente une forte pente et suggère qu’une saturation inférieure à 50 % n’est pas atteignable en pratique. L’exposant de saturation de l’indice de résistivité est de 1,7, plus faible que la valeur standard de 2. La couverture a une perméabilité de 27 nD, une porosité de 15 % et une diffusivité de 0,8 x 10-9 m2/s.

Background: Cancer treatment-related nausea and vomiting continue to be common and distressing symptoms for patients, despite improvements in antiemetics. Dietary modifications could potentially improve this symptom experience. Clinicians frequently provide dietary advice to patients, although the evidence base of such suggestions or recommendations is not clear. Purpose: This systematic review aimed to examine the current literature on food interventions associated with improvements in cancer treatment-related nausea and vomiting. Methods: Eight electronic databases were searched with a specific search term strategy covering trials without time or language limitations. Eligible studies focused on a food substance, defined as any nutritious substance that people eat or drink to maintain life and well-being. Trials in children and adults during chemotherapy or radiotherapy were included. Cochrane risk of bias tool was used to assess trial quality and GRADE was used to assess the certainty in the effect of each outcome. Results: Seventeen trials were included, 3 focusing on children and 14 on adults. Two trials included patients receiving radiation. Ten out of 17 trials (59%) had a high risk of bias. Strongest evidence with highest certainty was found for dietary counseling to meet macronutrient requirements in reducing incidence of radiotherapy-related nausea and vomiting in adults (n=2 studies; n=124 participants; GRADE level: moderate). There was also moderate certainty in the beneficial effect of protein supplementation on nausea and vomiting incidence in adults during radiotherapy (n=2 studies; n=124 participants; GRADE level: moderate). A significant positive effect on CINV incidence and/or severity in adults was also found for dietary counseling to meet macronutrient requirements during chemotherapy, a peppermint drink, scaly wood mushroom, chamomile, protein with ginger, and a colorless odorless diet (GRADE level: low to very low). Conclusions: The review identified food-based approaches that could improve the nausea and vomiting experience in patients with cancer and provide guidance to clinicians. However, confidence in these findings was low and studies were heterogeneous and mostly of low quality, requiring further investigation before stronger recommendations can be made. Future research is needed to confirm efficacy and safety. Trial registration: PROSPERO [ABSTRACT FROM AUTHOR]

Atmospheric microplasma jets (MPJs) sustained in rare gases have gained increased attention due to their potential to generate highly reactive species. In this paper, we present space- and time-resolved argon metastable densities, Ar(1s5), measured in an atmospheric pressure MPJ operated in Ar and propagating into ambient air using tunable diode laser absorption spectroscopy (1s5 → 2p9 optical transition). The MPJ was produced using a dielectric barrier discharge energized by short duration (230 ns) high-voltage positive pulses (4.2–6.2 kV) at a repetition frequency of 20 kHz. The spectral absorption line profile was recorded and allowed measurements of the absolute metastable Ar(1s5) density integrated in the line-of-sight of the laser beam under various operating conditions of the MPJ. The results reveal a sensitive dependence of the Ar(1s5) density on spatial coordinates, i.e., distance from the exit of the capillary tube of the discharge and from the axis of the argon jet. The highest Ar(1s5) densities of about 3 × 1013 cm−3 were measured at the axis of the argon jet at longitudinal distances between 4 and 5.5 mm downstream from the nozzle of the tube. The temporal distribution of the Ar(1s5) density, which presents three maxima, is thoroughly discussed in this paper. The spatial distribution of the effective Ar(1s5) lifetime (<250 ns) is also reported, giving some insight into the surrounding environment of the argon metastable atoms. The determined spatiotemporal distributions of the Ar(1s5) density can be useful for the optimization of argon MPJs for different applications like surface or biomedical processes. [ABSTRACT FROM AUTHOR]

Spontaneous imbibition processes can play an important role in oil production. It can be enhanced or influenced by wettability changes generated by properly designed chemicals or by the natural surfactants resulting from reactive crude oils in the presence of alkaline solutions. The reaction of basic salts with some components of oil can, indeed, lead to the formation of natural soaps that reduces the interfacial tension between oil and brine. The latter scenario is studied herein on samples and oil from the St Ulrich oil field in the Vienna basin. To that end, spontaneous imbibition experiments were performed with two brines differing by the absence or presence of alkali. We first present a general novel technique to monitor saturation changes on small rock samples for the purpose of assessing the efficiency of a given recovery process. Samples of only 15 mm in diameter and 20 mm in length and set at irreducible saturation were fully immersed in the solution of interest, and the evolution of the samples’ saturation with time was monitored thanks to a dedicated NMR technique involving the quantification of the sole oil phase present within the sample. A fully-3D imbibition configuration was adopted, involving counter-current flows through all faces of the sample. The experimental method is fast for two reasons: (i) the kinetics of capillary imbibition process is proportional to the square of sample size, i.e. very rapid if accurate measurements can be acquired on tiny samples, (ii) the present 3D situation also involves faster kinetics than the 1D configuration often used. The NMR technique was crucial to achieve such conditions that cannot be satisfied with conventional volumetric methods. The kinetics of oil desaturation during spontaneous imbibition is interpreted with the help of an analytical 3D diffusion model. For the alkaline solution, the diffusion coefficient is reduced by a factor of only two compared to the non-alkaline brine, although the interfacial tension between the oil and the imbibing solution is reduced by a factor of 10. Hence, a wettability change to a more water wet state has to be assumed when the alkaline solution replaces the non-alkaline solution in the imbibition process. However, no significant impact on the final saturation was observed.

An overview of the three-year program and results of the Geocarbone-Integrity French project is given. It focused on the development of experimental and numerical methodologies to assess the integrity of underground CO2 storage at various scales. The primary criteria in the selection of a caprock formation for CO2 storage purposes are the thickness and permeability of the formation. Local and limited migration of CO2 into the caprock due to insufficient capillary entry pressure has been studied as a probable scenario. At a large scale, caprock characterization requires at least seismic profiles to identify lateral continuity. When well-logging data are available, simple rules based on clay content can be used to estimate thicknesses. For the formation considered, the geochemical reactivity to CO2 was small, making the reaction path difficult to identify. Similarly, artificial alterations of samples representing extreme situations had little impact on geomechanical properties. Finally, with realistic overpressure due to injection, shear fracture reactivation criteria are not reached and migration of CO2 either by diffusion or by two-phase flow within the first meters of the caprock produce mostly a decrease in porosity by precipitation, and very locally an increase in porosity by dissolution. Un aperçu du programme et des résultats du projet multipartenaire Géocarbone-Intégrité est donné. Il concerne le développement de méthodes expérimentales et numériques pour évaluer l'intégrité d'un stockage de CO2. Les critères essentiels d'une couverture sont l'épaisseur de la formation et sa perméabilité. Une migration locale et limitée du CO2 dans la couverture due à une pression capillaire d'entrée insuffisante est étudiée dans ce travail. À grande échelle, des profils sismiques sont nécessaires pour caractériser la continuité d'une couverture. Quand on dispose de données de puits, des critères simples pour estimer l'argilosité peuvent être utilisés. On montre également que les techniques de lithosismique peuvent être appliquées aux couvertures. Pour les formations considérées, nous n'avons pas observé au laboratoire de réactivité géochimique importante, ni d'effet marquant sur les propriétés mécaniques. Des simulations hydromécaniques à grande échelle montrent que les critères de rupture ou de réactivation de fractures préexistantes ne sont pas satisfaits. Des simulations de transport réactif par diffusion et écoulement diphasique dans la couverture montrent une migration du CO2 sur une dizaine de mètres au plus et une baisse de la porosité par précipitation, et localement une augmentation de la porosité par dissolution.

The efficiency of geological storage of CO2 lies in the confinement properties of the caprock. Among these properties, diffusive characteristics play an important, though sometimes underestimated, role. Although diffusion is a slow process, it can play a significant role in the long run. Besides, the desirable properties for a caprock – mainly high entry pressure and low permeability – are by no means contradictory with relatively high diffusion coefficients; the reason is that all these quantities do not depend on the same geometrical properties of the porous matrix (pore size in one case, tortuosity in the other). Within the framework of the Géocarbone-INTÉGRITÉ project, financed by the National Research Agency ANR from 2006 to 2008, the diffusion coefficients for water and bicarbonate ions have been measured in caprock samples from three levels (Comblanchien and Dalle Nacrée formations). These two species cover the main situations encountered in storage site conditions (neutral/charged species, interacting or not with the solid matrix). The model used for interpretation of the experiments is presented; this enables review of various quantities of interest: effective diffusion coefficient, pore diffusion coefficient, apparent diffusion coefficient, retardation factor. The pore self-diffusion coefficient for water was measured by two different techniques (Nuclear Magnetic Resonance and tritiated water 1H3HO tracing) on two samples. The results are comparable: porosity about 6%, pore diffusion coefficient 2 × 10−10 m2/s, tortuosity about 10. The radioactive tracer method is then applied with tritiated water and carbon-14-tagged bicarbonate ions, H1CO-3, to samples from three depth levels. Reduction of accessible porosity is evidenced for bicarbonate ions, which is attributed to anionic exclusion. Interaction between bicarbonate ions and the solid matrix is also shown. This suggests that additional CO2storage capacity might be offered by carbonated caprocks (regardless of the problem of alteration by acidified water, not addressed here). Lastly, a few simple rules for extending the results presented here to other experimental conditions are proposed. L’efficacite d’un stockage geologique de CO2 repose sur les proprietes de confinement des roches de couverture. Parmi ces proprietes, les caracteristiques diffusives jouent un role important qui est parfois sous-estime. En effet, la diffusion est un processus lent mais qui peut s’averer non negligeable sur le long terme. De plus, les caracteristiques recherchees pour une roche de couverture, principalement une forte pression d’entree et une faible permeabilite, ne sont pas incompatibles avec des coefficients de diffusion relativement eleves, puisque ces grandeurs sont liees a des caracteristiques geometriques differentes (schematiquement, les tailles de pore pour les unes et la tortuosite pour les autres). Dans le cadre du projet Geocarbone–INTEGRITE, finance par l’ANR de 2006 a 2008, on a donc mesure les coefficients de diffusion de l’eau et de l’ion bicarbonate dans des echantillons de roche de couvertures carbonatees provenant de trois niveaux (formations des Calcaires du Comblanchien et de la Dalle Nacree). Ces deux especes permettent en effet de couvrir, en premiere approximation, les situations rencontrees en conditions de stockage (espece neutre/espece chargee, interagissant ou non avec la matrice solide). Dans un premier temps, on presente le modele simple de diffusion utilise pour le depouillement des experiences, ce qui permet de passer en revue les differentes grandeurs utiles : coefficient de diffusion effectif, coefficient de diffusion de pore, coefficient de diffusion apparent, porosite accessible, facteur de retard. Le coefficient d’autodiffusion de l’eau est mesure par deux techniques differentes (Resonance Magnetique Nucleaire et tracage radioactif a l’eau tritiee 1H3HO) dans deux echantillons. Les resultats obtenus sont comparables : porosite de l’ordre de 6 %, coefficient de diffusion de pore de l’ordre de 2 × 10−10 m2/s, tortuosite proche de 10. Le tracage de l’eau tritiee et de l’ion bicarbonate marque au carbone 14, H1CO-3, est ensuite applique aux trois types d’echantillons. Il met en evidence une diminution de la porosite accessible a l’ion bicarbonate, diminution que l’on attribue a l’exclusion anionique. L’interaction entre l’ion bicarbonate et la matrice solide est egalement visible – ce qui suggere une capacite de stockage du CO2 dans les roches de couverturecarbonatees (independamment des problemes de leur alteration par l’eau acidifiee, qui n’est pas aborde). Enfin, on propose quelques regles simples de transposition des resultats obtenus a d’autres conditions experimentales.

Recently, many plant-derived bioactive agents have been included in dermo-cosmetics formulations. This leads to an extensive portfolio of innovative products with an expanded range of benefits, including anti-aging, antioxidant, hydrating and depigmenting. Although different technologies drawing on science and nature are used to create these high-performing molecules, there remains some debate about the mechanism of action of the natural bioactive ingredients within dermo-cosmetics. This review recapitulates the main biological mechanisms underlying the activity of natural active ingredients, with a specific focus on their synergistic use for the management of common, yet quite specific, skin conditions. A total of 28 plant-derived bioactives were selected from the Givaudan Active Beauty (Argenteuil, France) portfolio, a multinational company specializing in innovative natural actives research. An extensive literature review about their biological activity was conducted by a PubMed search using different keywords. No language or publication date restrictions were used. Givaudan Active Beauty data on file were also considered. The bioactive ingredients were described according to the pathogenetic mechanisms underlying 10 common skin conditions that dermo-cosmetics may address. Literature data have shown that plant-derived bioactives are involved in a wide range of biological mechanisms showing anti-inflammatory, antioxidant, and moisturizing properties, along with skin barrier protection and collagen synthesis activities. As a result, different combinations of bioactives within dermo-cosmetics can be defined to counteract simultaneously the different pathogenetic mechanisms underlying different skin conditions. Available literature supports the synergistic use of plant-derived bioactive agents within dermo-cosmetics as a viable and safe option for managing the most common skin conditions. [ABSTRACT FROM AUTHOR]

Nous décrivons quelques aspects de la RMN en milieux poreux qui intéressent le pétrophysicien et le diagraphiste : une mesure utile pour la caractérisation de structures poreuses et pour la distribution de fluides dans le volume poreux. Les bases de l'interprétation des diagraphies RMN en termes de saturation découlent des considérations présentées. Notre analyse s'appuie essentiellement sur une analyse approfondie de la littérature (pétrolière en particulier) et sur des travaux récents effectués à l'Institut Français du Pétrole. We describe some aspects of NMR in a porous medium that are of interest to both petrophysicists and log analysts, that is, measurements that are useful for characterizing porous structures and for determining the distribution of fluids in a porous volume. The principles for interpreting NMR saturation logs follow from these considerations. Our analysis is based essentially on a thorough study of the literature, with particular emphasis on petroleum, and on recent work carried out at the Institut Français du Pétrole.