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Literatura académica sobre el tema "Volume de pore inaccessible"

Autor: Grafiati

Publicado: 25 de mayo de 2024

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Artículos de revistas sobre el tema "Volume de pore inaccessible"

Gilman, J. R. y D. J. MacMillan. "Improved Interpretation of the Inaccessible Pore-Volume Phenomenon". SPE Formation Evaluation 2, n.º 04 (1 de diciembre de 1987): 442–48. http://dx.doi.org/10.2118/13499-pa.

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Sotirchos, Stratis V. y Solon Zarkanitis. "Inaccessible pore volume formation during sulfation of calcined limestones". AIChE Journal 38, n.º 10 (octubre de 1992): 1536–50. http://dx.doi.org/10.1002/aic.690381006.

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Bahadur, Jitendra, Cristian R. Medina, Lilin He, Yuri B. Melnichenko, John A. Rupp, Tomasz P. Blach y David F. R. Mildner. "Determination of closed porosity in rocks by small-angle neutron scattering". Journal of Applied Crystallography 49, n.º 6 (2 de noviembre de 2016): 2021–30. http://dx.doi.org/10.1107/s1600576716014904.

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Small-angle neutron scattering (SANS) and ultra-small-angle neutron scattering (USANS) have been used to study a carbonate rock from a deep saline aquifer that is a potential candidate as a storage reservoir for CO2sequestration. A new methodology is developed for estimating the fraction of accessible and inaccessible pore volume using SANS/USANS measurements. This method does not require the achievement of zero average contrast for the calculation of accessible and inaccessible pore volume fraction. The scattering intensity at highQincreases with increasing CO2pressure, in contrast with the low-Qbehaviour where the intensity decreases with increasing pressure. Data treatment for high-Qscattering at different pressures of CO2is also introduced to explain this anomalous behaviour. The analysis shows that a significant proportion of the pore system consists of micropores (<20 Å) and that the majority (80%) of these micropores remain inaccessible to CO2at reservoir pressures.

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Xiong, Lei, Yu Huang, Yuewei Wu, Chaochao Gao y Wenxi Gao. "Study on the Influence of Inaccessible Pore Volume of Polymer Development". IOP Conference Series: Earth and Environmental Science 170 (julio de 2018): 022045. http://dx.doi.org/10.1088/1755-1315/170/2/022045.

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Lund, T., E. Ø. Bjørnestad, A. Stavland, N. B. Gjøvikli, A. J. P. Fletcher, S. G. Flew y S. P. Lamb. "Polymer retention and inaccessible pore volume in North Sea reservoir material". Journal of Petroleum Science and Engineering 7, n.º 1-2 (abril de 1992): 25–32. http://dx.doi.org/10.1016/0920-4105(92)90005-l.

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Rusin, Zbigniew, Piotr Stępień y Karol Skowera. "Influence of fly ash on the pore structure of mortar using a differential scanning calorimetry analysis". MATEC Web of Conferences 322 (2020): 01027. http://dx.doi.org/10.1051/matecconf/202032201027.

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In the paper a low-temperature thermoporometry using differential scanning calorimetry (DSC) was employed for analyse of influence of siliceous fly ash (FA) on pore structure of non-air-entrained mortars (pore size, connectivity). A method of interpreting a heat flux differential scanning calorimetry records in pore structure was used for this purpose. The results demonstrated that the: (i) fly ash mortars have virtually no pores inaccessible to water, unlike the mortars with plain Portland cement in which inaccessible pores constitute a significant fraction, growing with the increase in w/b; (ii) with a decrease in w/b the ink-bottle volume decreases. Fraction of this pore type is relatively larger in fly ash mortars; (iii) Siliceous fly ash increased the volume of pores greater than 8 nm, in particular in the group with radii larger than 20 nm at all w/b ratios.

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Lan, Yuzheng, Rouzbeh Ghanbarnezhad Moghanloo y Davud Davudov. "Pore Compressibility of Shale Formations". SPE Journal 22, n.º 06 (17 de agosto de 2017): 1778–89. http://dx.doi.org/10.2118/185059-pa.

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Summary This study introduces a novel outlook on a shale-pore system and on the potential effect of pore compressibility on the production performance. We divide porosity of the system into accessible and inaccessible pores, and incorporate inaccessible pores with grains into the part of the rock that is not accessible. In general, accessible pores contribute to flow directly, whereas inaccessible pores do not. We present a mathematical model that uses mercury-injection capillary pressure (MICP) data to determine the accessible-pore and inaccessible part of the rock (IRP) compressibility as a function of pressure. During MICP testing in a typical shale sample, the rock sample experiences conformance, compression, and intrusion as effective pressure increases. We characterize the compressibility value dependent on MICP data as a function of pressure. The calculated compressibility values for accessible pores generally appear to be much greater (two to three orders of magnitude) than those of IRP. Next, we evaluate how calculated accessible-pore-compressibility values affect gas recovery in several shale-gas plays. Our results suggest that substitution of total pore compressibility with accessible-pore compressibility can significantly change the reservoir-behavior prediction. The fundamental rock property used in many reservoir-engineering calculations including reserves estimates, reservoir performance, and production forecasting is the total pore-volume (PV) compressibility, which has an approximate value typically within the range of 1 × 10−6 to 1 × 10−4 psi−1 (Mahomad 2014). By recognizing the part of the pore system that actually contributes to production and identifying its compressibility, we can substitute total pore compressibility with accessible-pore compressibility. The result changes the value by nearly two orders of magnitude. The outcome of the paper changes the industry's take on prediction of reservoir performance, especially the rock-compaction mechanism. This study finds that production caused by rock compaction is in fact much greater than what has often been regarded, which will change the performance evaluation on a great number of reservoirs in terms of economic feasibility.

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Ferreira, V. H. S. y R. B. Z. L. Moreno. "Rheology-based method for calculating polymer inaccessible pore volume in core flooding experiments". E3S Web of Conferences 89 (2019): 04001. http://dx.doi.org/10.1051/e3sconf/20198904001.

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Polymer flooding is an enhanced oil recovery (EOR) method that reduces the mobility ratio between the displaced oil and the displacing injected water. The flow of polymer solutions through porous media is subject to some process-specific phenomena, such as the inaccessible pore volume (IAPV). Due to IAPV, polymer molecules move faster through the porous medium than smaller ones. Thus the IAPV value needs to be accounted for in experiments and field projects. Recent reports found that polymer in-situ rheology correlates with the IAPV. The objective of this paper is to develop a method for estimating IAPV based on the in-situ rheology of polymers. The methodology proposed here can be used in both single- and two-phase experiments. The technique requires measurement of polymer resistance factor (RF) and residual resistance factor (RRF) at steady state conditions. Core permeability, porosity, and residual oil saturation, as well as water and polymer bulk viscosities, also need to be taken into account. Correlations for polymer in-situ viscosity and shear rate are solved simultaneously, to wield an estimative for the IAPV. Aiming at to prove the method, we report 16 core-flooding experiments, eight single- and eight two-phase experiments. We used a flexible polymer and sandstone cores. All the tests were run using similar rock samples. In the single-phase experiments, we compare the alternative method with the classic tracer method to estimate IAPV. The results show an average relative difference of 11.5% between the methods. The two-phase results display, on average, an 18% relative difference to the IAPV measured in the single-phase experiments. The difference between single- and two-phase results can be an effect of the higher shear rates experienced in the two-phase floodings since, in these cases, the aqueous phase shear rate is also dependent on the phase saturation. Additionally, temperature, core length, pore pressure, and iron presence on the core did not show any influence on the IAPV for our two-phase experiments. The method proposed in this paper is limited by the accuracy of the pressure drop measurements across the core. For flexible polymers, the method is valid only for low and mid shear rates, but, accoording to literature, for rigid polymers the method should be accurate for a broad range of shear rates. The method proposed here allows the measurement of polymer IAPV on two- and single- phase core-flooding experiments when a tracer is not used.

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Leng, Jianqiao, Xindi Sun, Mingzhen Wei y Baojun Bai. "A Novel Numerical Model of Gelant Inaccessible Pore Volume for In Situ Gel Treatment". Gels 8, n.º 6 (13 de junio de 2022): 375. http://dx.doi.org/10.3390/gels8060375.

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Inaccessible pore volume (IAPV) can have an important impact on the placement of gelant during in situ gel treatment for conformance control. Previously, IAPV was considered to be a constant factor in simulators, yet it lacked dynamic characterization. This paper proposes a numerical simulation model of IAPV. The model was derived based on the theoretical hydrodynamic model of gelant molecules. The model considers both static features, such as gelant and formation properties, and dynamic features, such as gelant rheology and retention. To validate our model, we collected IAPV from 64 experiments and the results showed that our model fit moderately into these lab results, which proved the robustness of our model. The results of the sensitivity test showed that, considering rheology and retention, IAPV in the matrix dramatically increased when flow velocity and gelant concentration increased, but IAPV in the fracture maintained a low value. Finally, the results of the penetration degree showed that the high IAPV in the matrix greatly benefited gelant placement near the wellbore situation with a high flow velocity and gelant concentration. By considering dynamic features, this new numerical model can be applied in future integral reservoir simulators to better predict the gelant placement of in situ gel treatment for conformance control.

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Hilden, Sindre T., Halvor Møll Nilsen y Xavier Raynaud. "Study of the Well-Posedness of Models for the Inaccessible Pore Volume in Polymer Flooding". Transport in Porous Media 114, n.º 1 (15 de junio de 2016): 65–86. http://dx.doi.org/10.1007/s11242-016-0725-8.

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Tesis sobre el tema "Volume de pore inaccessible"

Dongmo, Nguepi Guissel Lagnol. "Modèles mathématiques et numériques avancés pour la simulation du polymère dans les réservoirs pétroliers". Electronic Thesis or Diss., université Paris-Saclay, 2021. http://www.theses.fr/2021UPASG077.

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Une technique efficace pour accroître la production d’un champ pétrolier consiste à y injecter un mélange d’eau et de polymère. La viscosité du polymère réduit en effet la mobilité de l’eau, qui pousse alors mieux l’huile, d’où un taux d’extraction plus élevé. La simulation numérique d’un tel procédé de récupération d’hydrocarbures revêt donc d’une importance capitale. Or, malgré des décennies de recherche, la modélisation des écoulements avec polymère en milieu poreux et sa résolution numérique demeurent un sujet difficile. D’une part, les modèles habituellement employés par les ingénieurs de réservoir présentent, au mieux, des singularités de type résonance qui les rend faiblement hyperboliques. Ce défaut donne lieu à certaines complicationsD’une part, les modèles habituellement employés par les ingénieurs de réservoir présentent, au mieux, des singularités de type résonance qui les rend faiblement hyperboliques. Ce défaut donne lieu à certaines complications mais reste acceptable. Au pire, quand on veut incorporer l’effet du volume de pore inaccessible (IPV), les modèles deviennent non hyperboliques, ce qui aggrave les instabilités numériques susceptibles d’apparaître.D’autre part, les schémas numériques classiques ne conduisent pas à des résultats satisfaisants. Sans IPV, la diffusion excessive autour de l’onde de contact fait perdre les informations pertinentes. Avec IPV, l’existence des valeurs propres complexes crée des instabilités exponentielles au niveau continu qu’il faut traiter au niveau discret sous peine d’arrêt prématuré du code.L’objectif de cette thèse est de remédier à ces difficultés. Au niveau des modèles, nous analysons plusieurs lois d’IPV et établissons une équivalence entre deux d’entre elles. Nous proposons de surcroît des conditions suffisantes raisonnables sur la loi d’IPV en vue de l’hyperbolicité faible du système d’écoulement. Au niveau des schémas pour le problème sans IPV, nous préconisons une correction afin d’améliorer la précision des discontinuités de contact. Pour le problème avec IPV,nous élaborons une méthode de relaxation qui garantit la stabilité des calculs quelle que soit la loi IPV
An effective technique to increase production in an oil field is to inject a mixture of water and polymer. The viscosity of polymer reduces the mobility of water, which then pushes oil better, resulting in a higher extraction rate. The numerical simulation of such an enhanced oil recovery is therefore of paramount importance. However, despite decades of research, the modeling of polymer flows in porous media and its numerical resolution remains a difficult subject.On the one hand, the models traditionally used by reservoir engineers exhibit, in the best case, resonance-like singularities that make them weakly hyperbolic. Thisdefect gives rise to some complications but remains acceptable. In the worst case, when we wish to incorporate the effect of the inaccessible pore volume (IPV), themodels become non-hyperbolic, which exacerbates the numerical instabilities that are likely to appear.On the other hand, classical numerical schemes do not yield satisfactory results. Without IPV, the excessive diffusion around the contact wave causes the most relevant information to be lost. With IPV, the existence of complex eigenvalues generates exponential instabilities at the continuous level that must be addressed at the discrete level to avoid a premature stop of the code.The objective of this thesis is to remedy these difficulties. Regarding models, we analyze several IPV laws and show an equivalence between two of them. Furthermore, we propose reasonable sufficient conditions on the IPV law to enforce weak hyperbolicity of the flow system. Regarding schemes for the problem without IPV, we advocate a correction to improve the accuracy of contact discontinuities. For the problem with IPV, we design a relaxation method that guarantees the stability of the calculations for all IPV laws

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Adams, Aaron J. "Relationships between observed pore and pore-throat geometries, measured porosity and permeability, and indirect measures of pore volume by nuclear magnetic resonance". Texas A&M University, 2005. http://hdl.handle.net/1969.1/4710.

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Carbonate reservoirs are a network of pores and connecting pore-throats that contain at least half of the world's oil. Genetic classification of carbonate pores enables one to map the pore types that have greatest influence on reservoir performance. Though NMR logging has been used to estimate pore sizes, it has not been used to identify genetic pore types or to aid in determinations of reservoir quality for different pore assemblages. Five genetic pore types identified in 40 carbonate and 7 sandstone samples were subjected to NMR measurements. Results reveal close correspondence between NMRderived pore volumes and 2-D pore size and shape gleaned from petrographic image analysis. Comparisons of real and synthetic pore shapes showed that shapes of all pore types in the medium size range of 0.02-0.5mm can be reliably compared with synthetic varieties, but such comparisons were unreliable for vuggy pores smaller than 0.5mm. T2 relaxation times for depositional pores exhibit low amplitude, narrow wavelength responses. Moldic pores produced medium amplitude, asymmetrical wavelength responses, and intercrystalline pores show high amplitude, narrow wavelength responses. NMR-derived pore volumes on pores with ferroan dolomite interiors underestimated pore diameter by up to 3 orders of magnitude. Calculated pore-throat sizes from MICP data correlate strongly with measured permeability. Samples with high, intermediate, or low poroperm values displayed characteristic T2 curves confirming that reservoir quality can be estimated from NMR measurements. Future work is expected to show that NMR logging can estimate reservoir quality at field scale and aid in mapping flow units in compartmentalized reservoirs.

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Holmes, Gary John. "Early age volume change and pore pressure development in cement pastes". Thesis, Queen Mary, University of London, 1995. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.243815.

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Bunker, Daniel Thomas. "The Influence of drying rate on the pore volume distribution of clay coatings". Diss., Georgia Institute of Technology, 1991. http://hdl.handle.net/1853/5783.

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Panontin, Flavia. "Determinação de volume de poro de silicas para CLAE utilizando espectroscopia no infravermelho proximo". [s.n.], 2007. http://repositorio.unicamp.br/jspui/handle/REPOSIP/250552.

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Orientador: Ivo Milton Raimundo Junior
Dissertação (mestrado) - Universidade Estadual de Campinas, Instituto de Quimica
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Resumo: Um método para a determinação do volume de poros de sílicas, utilizadas como suportes de fases estacionárias para CLAE (Cromatografia Líquida de Alta Eficiência), foi desenvolvido utilizando a espectroscopia na região do infravermelho próximo (NIR). Foram preparadas amostras pela adição de sílica em soluções de diferentes concentrações de compostos de recobrimento, como polímeros, hidrocarbonetos lineares e ramificados, nujol, glicerol, entre outros, em meio de diclorometano ou metanol. Foram registrados espectros de reflectância difusa na região de 1100 a 2300 nm. Os espectros obtidos foram submetidos à primeira derivada e as intensidades em 1688 nm (primeiro sobretom de ligações C-H) foram empregadas para a construção de uma curva em função da carga inicial (massa recobrimento/massa total) da amostra. Foram obtidos dois ramos lineares, o primeiro (praticamente paralelo à abscissa) indica que a imobilização do reagente no interior dos poros da sílica, e o segundo mostra um aumento crescente dos valores de primeira derivada, indicando o recobrimento de sua superfície externa. A intersecção destas duas retas fornece o valor de carga equivalente ao total preenchimento dos poros. Os resultados obtidos de volume de poro são concordantes com os valores fornecidos pelo método padrão (BJH), apresentando desvios padrão menores que 10%. O método proposto apresenta boa reprodutibilidade, com desvios menores que 1,0%, sendo rápido, simples e não destrutivo o que mostra uma grande vantagem frente ao método BJH, que faz uso de equipamentos caros e procedimentos lentos
Abstract: A method for the determination of pore volume of silicas, used as stationary phases for HPLC (High Performance Liquid Chromatography) was developed using near infrared spectroscopy (NIR). Samples were prepared by the addition of silica in covering compounds solutions of different concentrations, as linear and ramified polymers, hydrocarbons, nujol, glycerol, and among others, using dichloromethane or methanol as solvents. Diffuse reflectance spectra were registered in the 1100 to 2300 nm region. Spectra were submitted to a first derivative pre-treatment and the intensities at 1688 nm (first overtone of C-H bonds) were used for the construction of a curve as a function of the initial load (covering/total mass) of the sample. Two linear branches were obtained; the first one (practically parallel to the abscissa) indicates the immobilization of the reagent in the interior silica pores, and the second one shows increasing values of first derivative, indicating the covering of its external surface. The intersession of these two straight lines supplies the load value that is equivalent to the total fulfilling of the pores. The results obtained for of pore volume are in agreement with those supplied by the standard method (BJH), presenting deviation lower than 10 %. The proposed method presents good reproducibility with standard deviation lower than 1.0 %, being fast, simple and no destructive technique, that is a great advantage over the BJH method, which uses expensive equipment and slow procedures
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Quimica Analitica
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Huang, Baiyu. "Facile Synthesis and Improved Pore Structure Characterization of Mesoporous γ-Alumina Catalyst Supports with Tunable Pore Size". BYU ScholarsArchive, 2013. https://scholarsarchive.byu.edu/etd/3553.

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Mesoporous γ-alumina is the most extensively used catalysts support in a wide range of catalytic processes. The usefulness of γ-alumina relies on its favorable combination of physical, textural, thermal, and chemical properties. Pore structure properties are among the most important properties, since high surface area and large pore volume enable higher loading of active catalytic phases, while design of pore size and pore size distribution is critical to optimize pore diffusional transport and product selectivity. In addition, accurate determination of surface area (SA), pore volume (PV) and pore size distribution (PSD) of porous supports, catalysts, and nanomaterials is vital to successful design and optimization of these materials and to the development of robust models of pore diffusional resistance and catalyst deactivation.In this dissertation, we report a simple, one-pot, solvent-deficient process to synthesize mesoporous γ-alumina without using external templates or surfactants. XRD, TEM, TGA and N2 adsorption techniques are used to characterize the morphologies and structures of the prepared alumina nanomaterials. By varying the aluminum salts or the water to aluminum molar ratio in the hydrolysis of aluminum alkoxides, γ-alumina with different morphologies and pore structures are synthesized. The obtained alumina nanomaterials have surface areas ranging from 210 m2/g to 340 m2/g, pore volumes ranging from 0.4 cm3/g to 1.7 cm3/g, and average pore widths from 4 to 18 nm. By varying the alcohols used in the rinsing and gelation of boehmite/bayerite precursors derived from a controlled hydrolysis of aluminum alkoxides, the average pore width of the γ-aluminas can be tuned from 7 to 37 nm. We also report improved calculations of PSD based on the Kelvin equation and a proposed Slit Pore Geometry model for slit-shaped mesopores of relatively large pore size (>10 nm). Two structural factors, α and β, are introduced to correct for non-ideal pore geometries. The volume density function for a log normal distribution is used to calculate the geometric mean pore diameter and standard deviation of the PSD. The Comparative Adsorption (αs) Method is also employed to independently assess mesopore surface area and volume.

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Karakas, Z. K., R. Boncukcuoglu y I. H. Karakas. "The Effects of Fuel Type Above Adsorbtive Properties of the Nickel Ferrite Nanoparticles synthesized with Microwave Method". Thesis, Sumy State University, 2013. http://essuir.sumdu.edu.ua/handle/123456789/35271.

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In this study, we were able to develop a new and practical method for the synthesis of the NiFe2O4 nanoparticles. The synthesis of nickel ferrite nanoparticles was used various fuel substances such as glycine, urea and citric acid. The synthesis mixture prepared in stoichiometric rates was put in to the kitchen type microwave oven. In the end of reaction time was obtained a brown-black solid. The obtained solid was characterized with X-Ray Powder Diffraction and Scanning Electron Microscopy. The results of this analysis showed that all of the obtained particles has got nano-size particle size distribution. Later, the nanoparticles were analyzed by using a surface area analyzer and their adsorptive properties were investigated such as surface area and average pore size. We observed that the nanoparticles prepared with urea has the highest surface area. However, fuel type used in synthesis is quite effective on the surface properties of NiFe2O4 nanoparticles. When you are citing the document, use the following link http://essuir.sumdu.edu.ua/handle/123456789/35271

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Amgarten, Dione Rodrigues. "Determinação do volume especifico de poros de silicas cromatograficas por dessorção de liquidos em excesso". [s.n.], 2006. http://repositorio.unicamp.br/jspui/handle/REPOSIP/250692.

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Orientador: Kenneth Elmer Collins
Dissertação (mestrado) - Universidade Estadual de Campinas, Instituto de Quimica
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Resumo: A determinação do volume específico de poros (sV) de sílicas cromatográficas do tipo CLAE é importante porque o sV e uma característica fundamental da sílica que se relaciona diretamente aos parâmetros importantes (tamanho de poro e área superficial) para aplicações cromatográficas. A determinação do sV é normalmente feita por aparelhos de adsorção/dessorção de nitrogênio (baixas temperaturas: ~75K)) e de intrusão de mercúrio (alta pressão). A instrumentação usada nestes procedimentos é bastante cara e requer operadores bem treinados. Por isso, o objetivo deste projeto foi desenvolver um procedimento relativamente rápido, confiável, de baixo custo e que pudesse ser realizado, por estudantes e técnicos com um treinamento especial mínimo, em qualquer laboratório. Começando com um procedimento de adsorção volumétrica, publicado na literatura, um novo procedimento de dessorção gravimétrica que usa a mesma amostra várias vezes (reciclagem) para obter determinações estatisticamente confiáveis foi desenvolvido. As influências da umidade e da mudança do líquido volátil utilizado foram avaliadas. Os resultados mostraram que independente do líquido volátil utilizado, o valor de sV é preciso e se encontra bem próximo dos valores obtidos pelos procedimentos instrumentais convencionais. O procedimento requer aproximadamente de 6-8 horas para 1-5 determinações. O procedimento pode ser empregado no próprio ambiente do laboratório sem interferência da umidade do ambiente. Comparações com os outros procedimentos mostram que os valores de sV obtidos são precisos e provavelmente mais exatos do que os fornecidos por estes outros
Abstract: The determination of the specific pore volume (sV) of chromatographic silicas of the type used in HPLC is important because the sV is a fundamental characteristic of the silica which relates directly to parameters (pore size and surface area) important to chromatography applications. The determination of sV is usually made by means of adsorption/desorption of nitrogen at low temperature (~75K) or of intrusion of mercury at high pressure. The instrumentation for these procedures are quite expensive, and require well trained operators. Therefore, the objective this project was to developed a relatively fast and reliable procedure, of low cost that could be accomplished at any laboratory by students or technicians with a minimum of special training. Starting with a volumetric adsorption procedure published in the literature a new gravimetric desorption procedure was developed which uses the same sample several times (recycling) to obtain statistically confident determinations. The influences of the humidity and of the choice of volatile liquid used in the desorption from silica were evaluated. The results show that, independent of the volatile liquid used, the sV value is precise and in close agreement with values obtained by the conventional instrumental procedures. The procedure requires about 6-8 hours to make 1-5 determinations in parallel. The procedure can be employed in a laboratory environment with neglible interference from ambient humidity. Comparisons with the other procedures show thet the sV values obtained are at least as precise and are probably as accurate as they are
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Quimica Analitica
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PANINI, FILIPPO. "Pore-scale characterization of rock images: geometrical analysis and hydrodynamic simulation". Doctoral thesis, Politecnico di Torino, 2022. http://hdl.handle.net/11583/2970983.

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Spencer, John M. "Comparing a low-volume piezometer to traditional wells in evaluating hydraulic lag caused by low-permeability sediments". [Tampa, Fla] : University of South Florida, 2008. http://purl.fcla.edu/usf/dc/et/SFE0002435.

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Libros sobre el tema "Volume de pore inaccessible"

Zamorani, E. y H. Blanchard. Pore Volume and Pore Size Distribution of Cement Samples Measured by a Modified Mercury Intrusion Porosimeter (Nuclear Science and Technology). European Communities / Union (EUR-OP/OOPEC/OPOCE), 1987.

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Thomas, Sabu, A. K. Haghi y Moein MehdiPour MirMahaleh. Foundations of Nanotechnology, Volume One: Pore Size in Carbon-Based Nano-Adsorbents. Apple Academic Press, Incorporated, 2014.

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Allen, Terence. Particle Size Measurement: Volume 1: Surface area and pore size determination Volume 2: Powder sampling and particle size measurement (Particle Technology Series). 5^a ed. Springer, 1996.

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Vincent, Gaffney y Fitch Simon, eds. Europe''s Lost Frontiers: Volume 1. Archaeopress Archaeology, 2022. http://dx.doi.org/10.32028/9781803272689.

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Europe’s Lost Frontiers was the largest directed archaeological research project undertaken in Europe to investigate the inundated landscapes of the Early Holocene North Sea – the area frequently referred to as ‘Doggerland’. Funded through a European Research Council Advanced Grant (project number 670518), the project ran from 2015 to 2021, and involved more than 30 academics, representing institutions spread geographically from Ireland to China. A vast area of the seabed was mapped, and multiple ship expeditions were launched to retrieve sediment cores from the valleys of the lost prehistoric landscapes of the North Sea. This data has now been analysed to provide evidence of how the land was transformed in the face of climate change and rising sea levels. This volume is the first in a series of monographs dedicated to the analysis and interpretation of data generated by the project. As a precursor to the publication of the detailed results, it provides the context of the study and method statements. Later volumes will present the mapping, palaeoenvironment, geomorphology and modelling programmes of Europe’s Lost Frontiers. The results of the project confirm that these landscapes, long held to be inaccessible to archaeology, can be studied directly and provide an archaeological narrative. This data will become increasingly important at a time when contemporary climate change and geo-political crises are pushing development within the North Sea at an unprecedented rate, and when the opportunities to explore this unique, heritage landscape may be significantly limited in the future.

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Berwick, Robert C. y Edward P. Stabler, eds. Minimalist Parsing. Oxford University Press, 2019. http://dx.doi.org/10.1093/oso/9780198795087.001.0001.

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This book is the first dedicated to linguistic parsing—the processing of natural language according to the rules of a formal grammar—in the minimalist framework. While the Minimalist Program has been at the forefront of generative grammar for several decades, it often remains inaccessible to computer scientists and others in adjacent fields. In particular, minimalism reveals a surprising paradox: human language is simpler than we thought, and yet it cannot be processed by the machinery used by computer scientists. In this volume, experts in the field show how to resolve this apparent paradox, and how to turn Chomsky’s abstract theories into working computer programs that can process sentences or make predictions about the time course of brain activity when dealing with language. The book will appeal to graduate students and researchers in formal syntax, computational linguistics, psycholinguistics, and computer science.

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Dodge, Jennifer. Nightmares and Dreams. Editado por Debra J. Davidson y Matthias Gross. Oxford University Press, 2018. http://dx.doi.org/10.1093/oxfordhb/9780190633851.013.24.

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Shale gas development rapidly transformed energy production when new techniques emerged in the late 1990s and 2000s. The combination of high-volume hydraulic fracturing and horizontal drilling, or “fracking,” allowed development in vast, previously inaccessible, “unconventional” oil and gas deposits. Fracking has been welcomed by many national governments as a purportedly low-greenhouse-gas-emitting, energy-security-providing windfall. But it has simultaneously motivated vehement local opposition, to some surprising political effect. Many jurisdictions around the globe now have bans on the practice. This chapter explores shale gas development as a contested “sociotechnical imaginary,” an imagined form of social order reflected in technological projects. Drawing on the controversy in New York in the United States, it demonstrates how the “drill, baby, drill” imaginary was debunked as groups framed it as inherently risky and dangerous, and sought to empower institutions supporting an alternative imaginary.

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Saylor, Eric. Vaughan Williams. Oxford University Press, 2022. http://dx.doi.org/10.1093/oso/9780190918569.001.0001.

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This single-volume life-and-works biography of Ralph Vaughan Williams provides a contemporary reassessment of one of the twentieth century’s most versatile, influential, and enduringly popular British musicians. Throughout his wide-ranging career—as composer, conductor, editor, scholar, folk-song collector, teacher, author, administrator, and philanthropist—Vaughan Williams worked tirelessly to improve the standards and quality of British musical life. His compelling and original musical language—inspired in part by elements drawn from English folk song, French impressionism, Wagnerian post-chromaticism, Tudor-era sacred music, and Anglican hymnody—presented a distinctively British response to musical modernism over his sixty-year-long career, and in works ranging from art songs for amateurs to perhaps the finest symphonic cycle of the twentieth century. Alternating between biographical and analytical chapters, it draws upon previously inaccessible primary sources alongside a wealth of secondary material to craft a concise and engaging overview of Vaughan Williams’s life and music.

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Jahoda, Christian y Christiane Kalantari, eds. Early West Tibetan Buddhist Monuments. Verlag der Österreichischen Akademie der Wissenschaften, 2021. http://dx.doi.org/10.1553/978oeaw87776.

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This edited volume with 16 original contributions is devoted to early, 10th–13th-century Buddhist monuments of historical Western Tibet. The results are, on the one hand, based on in-depth interdisciplinary field studies in Ladakh, Spiti, Kinnaur, Tsamda und Purang (today partly on Chinese, partly on Indian territory), on the other hand on the critical edition and analysis of hitherto unknown or inaccessible historiographical texts, among others of works by Guge Paṇḍita Drakpa Gyaltsen (1415–1486/98), which are dedicated partly to the foundation phase of the West Tibetan kingdom and the royal monk Yeshe Ö (947–1019), the leading religio-political figure in Western Tibet in the 10th/11th century. Preceded by an outline of macro-historical developments in Western Tibet from the 7th to the 15th century, the studies focus on the archaeology, architecture, art history and foundation phase of the monastery of Nyarma (10th century) (Ladakh), in addition on stelae in Purang and Tsamda dating to the 9th and 10th centuries, newly discovered murals at Tabo monastery in Spiti, illuminated Prajñāpāramitā MSS from Tabo and Pooh (in Upper Kinnaur), as well as wall-paintings and accompanying inscriptions in the Zhag cave temple (Tsamda) from the 13th century. This volume contributes significantly to the wider and deeper understanding of the religious, cultural, political and social developments of the entire West Tibetan language area, in particular during the formative phases of the West Tibetan kingdom from the 10th to the 13th centuries.

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Capítulos de libros sobre el tema "Volume de pore inaccessible"

Dongmo Nguepi, Guissel Lagnol, Benjamin Braconnier, Christophe Preux, Quang-Huy Tran y Christophe Berthon. "A Relaxation Method for the Simulation of Possibly Non-hyperbolic Polymer Flooding Models with Inaccessible Pore Volume Effect". En Finite Volumes for Complex Applications IX - Methods, Theoretical Aspects, Examples, 445–53. Cham: Springer International Publishing, 2020. http://dx.doi.org/10.1007/978-3-030-43651-3_41.

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Plant, Leigh D. y Steve A. N. Goldstein. "Two-Pore-Domain Potassium Channels". En Textbook of Ion Channels Volume II, 151–62. Boca Raton: CRC Press, 2023. http://dx.doi.org/10.1201/9781003096276-10.

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Canham, Leigh. "Pore Volume (Porosity) in Porous Silicon". En Handbook of Porous Silicon, 1–7. Cham: Springer International Publishing, 2014. http://dx.doi.org/10.1007/978-3-319-04508-5_13-1.

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Canham, Leigh. "Pore Volume (Porosity) in Porous Silicon". En Handbook of Porous Silicon, 135–42. Cham: Springer International Publishing, 2014. http://dx.doi.org/10.1007/978-3-319-05744-6_13.

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Canham, Leigh. "Pore Volume (Porosity) in Porous Silicon". En Handbook of Porous Silicon, 291–98. Cham: Springer International Publishing, 2018. http://dx.doi.org/10.1007/978-3-319-71381-6_13.

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ZEMAN, LEOS y GABRIEL TKACIK. "Pore Volume Distribution in Ultrafiltration Membranes". En Materials Science of Synthetic Membranes, 339–50. Washington, D.C.: American Chemical Society, 1985. http://dx.doi.org/10.1021/bk-1985-0269.ch016.

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Frede, H. G. "The importance of pore volume and pore geometry to soil aeration". En Soil Compaction and Regeneration, 25–29. London: Routledge, 2022. http://dx.doi.org/10.1201/9780203739365-3.

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Zhao, Wenfang y Xiaowu Tang. "The Effect of Pore Size Deformation on Multi-pore Model of Woven Geotextiles in Tension Test". En Proceedings of the 8th International Congress on Environmental Geotechnics Volume 2, 708–14. Singapore: Springer Singapore, 2018. http://dx.doi.org/10.1007/978-981-13-2224-2_88.

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Teufel, L. W. "Pore Volume Changes During Frictional Sliding of Simulated Faults". En Mechanical Behavior of Crustal Rocks, 135–45. Washington, D. C.: American Geophysical Union, 2013. http://dx.doi.org/10.1029/gm024p0135.

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Li, Guangyao, Liangtong Zhan y Sheng Dai. "Influence of Pore Distribution Characteristics on Relative Hydraulic Conductivity in Soil Covers—A Pore-Scale Numerical Investigation". En Proceedings of the 8th International Congress on Environmental Geotechnics Volume 2, 343–50. Singapore: Springer Singapore, 2018. http://dx.doi.org/10.1007/978-981-13-2224-2_42.

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Actas de conferencias sobre el tema "Volume de pore inaccessible"

Pancharoen, Monrawee, Marco Roberto Thiele y Anthony Robert Kovscek. "Inaccessible Pore Volume of Associative Polymer Floods". En SPE Improved Oil Recovery Symposium. Society of Petroleum Engineers, 2010. http://dx.doi.org/10.2118/129910-ms.

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Lotsch, T., T. Muller y G. Pusch. "The Effect of Inaccessible Pore Volume on Polymer Coreflood Experiments". En SPE Oilfield and Geothermal Chemistry Symposium. Society of Petroleum Engineers, 1985. http://dx.doi.org/10.2118/13590-ms.

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Dongmo, G., B. Braconnier, C. Preux, Q. Tran y C. Berthon. "Glimm and Finite Volume Schemes for Polymer Flooding Model with and Without Inaccessible Pore Volume Law". En ECMOR XVII. European Association of Geoscientists & Engineers, 2020. http://dx.doi.org/10.3997/2214-4609.202035090.

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Fedorov, Konstantin Mikhailovich, Tatyana Anatolyevna Pospelova, Aleksandr Vyacheslavovich Kobyashev, Aleksandr Yanovich Gilmanov, Tatyana Nikolaevna Kovalchuk y Aleksand Pavlovich Shevelev. "Determination of Adsorption-Retention Constants and Inaccessible Pore Volume for High-Molecular Polymers". En SPE Russian Petroleum Technology Conference. SPE, 2021. http://dx.doi.org/10.2118/206428-ms.

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Abstract The application of chemical enhanced oil recovery methods is based mainly on data from experiments. Determining the adsorption constants without destroying the sample remains a relevant problem. It is necessary for accurate data. The determination of filtration parameters of high-molecular polymers in a porous medium using special model is considered in this paper. The aim of the investigation is the solution of inverse problem of polymer transport with adsorption. The key data for this are the characteristic times of the polymer front propagation, water and rock densities, porosity, and initial polymer concentration. The solutions of the direct problem and the inverse problem from the characteristic form of equations are obtained. The algorithm of interpretation of adsorption-retention parameters and inaccessible pore volume form non-destructive experimental studies is developed. Comparison of the calculated values of the inaccessible pore volume with the results of laboratory studies leads to an error within 10%. The practical application of the algorithm was carried out using the data obtained in previously conducted experiments.

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Alves Fortunato, Maira, Samir Bekri, David Rousseau, Tiphaine Courtaud y Nicolas Wartenberg. "Transport of EOR Surfactant in Reservoirs: Impact of Polymer on Apparent Surfactant Inaccessible Pore Volume". En SPE EuropEC - Europe Energy Conference featured at the 84th EAGE Annual Conference & Exhibition. SPE, 2023. http://dx.doi.org/10.2118/214411-ms.

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Abstract Designing chemical EOR processes requires reservoir simulations that need to be backed by a good understanding of the mechanisms at play when injecting surfactant-based solutions in porous media. One of the main challenges is that laboratory coreflood tests often show early surfactant breakthroughs that cannot be easily history matched. Indeed, contrary to polymer macromolecules, smaller surfactant molecules are not supposed to experience the inaccessible pore volume (IPV) effect. The study's aim was to determine if, in surfactant-polymer flooding, the polymer could influence the transport of the surfactant in such a way that it would not be able to invade a fraction of the pore space. To that end, two multi-steps coreflood tests were performed with cores of outcrop rock in conditions representative of a reference field case. In the first test, the surfactant was injected without polymer and then, after a brine injection flush, with polymer. In the second test, the surfactant was directly injected with polymer. For both tests, in order to bypass the adsorption effect, the surfactant injected volumes at breakthrough were determined on rocks having their surface already fully saturated by surfactant. Namely, a first surfactant slug was injected in order to fulfill maximum rock adsorption capacity, then, immediately after, a second at a higher concentration of which the breakthrough was potentially influenced by IPV only. The polymer IPV were estimated by the conventional two-slugs method. In the first test, the result showed that, without polymer, the surfactant accessed all of the pore volume of the core while, in presence of polymer, the surfactant could not access about 2% of the pore volume, which corresponded to the polymer IPV. In the second test, the surfactant was not able to access 12% of the pore volume, which also corresponded to the polymer IPV. These outcomes stand as evidence that the presence of polymer impacts the transport of surfactant, leading it to experience an "apparent" surfactant IPV effect equal to the polymer's one. This suggests that interactions between polymer and surfactant molecules take place at the pore level. This study illustrates that surfactant transport properties in reservoirs can be more complex than conventionally accounted for in dynamic reservoir simulation. As history-matching of the coreflood essays is needed to build a representative dataset for surfactant-based EOR processes, improvements of the simulation software appear required for cases where IPV cannot be neglected.

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Swadesi, Boni, Erdico Prasidya Saktika, Mahruri Sanmurjana, Septoratno Siregar y Dyah Rini. "An experimental study of inaccessible pore volume on polymer flooding and its effect on oil recovery". En 2ND INTERNATIONAL CONFERENCE ON EARTH SCIENCE, MINERAL, AND ENERGY. AIP Publishing, 2020. http://dx.doi.org/10.1063/5.0006957.

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Swadesi, Boni, Roiduz Zumar, Mahruri Sanmurjana, Septoratno Siregar y Dedy Kristanto. "The effect of inaccessible pore volume and adsorption on polymer flooding for field scale injection in RZ field". En 3RD INTERNATIONAL CONFERENCE ON EARTH SCIENCE, MINERAL, AND ENERGY. AIP Publishing, 2021. http://dx.doi.org/10.1063/5.0065527.

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Li, Z., R. M. Dean, H. Lashgari, H. Luo, J. W. Driver, W. Winoto, G. A. Pope et al. "Recent Advances in Modeling Polymer Flooding". En SPE Improved Oil Recovery Conference. SPE, 2024. http://dx.doi.org/10.2118/218219-ms.

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Abstract New and improved physical property models have been added to the UTCHEM reservoir simulator to accommodate a broader range of polymer flooding applications and to improve its predictive capabilities. Accurate simulations of the chemistry and physics of polymer flooding are needed to design and optimize a polymer flood including the selection of the best polymer to use for specific reservoir conditions. The new polymer viscosity model implemented in UTCHEM can be used to calculate polymer viscosity more accurately as a function of polymer concentration, shear rate, salinity and hardness, temperature, and intrinsic viscosity. The new model is based on extensive polymer viscosity and rheological measurements. The improved polymer rheology is important for more reliable predictions of polymer injectivity and reservoir sweep. A hydrolysis model has been added to UTCHEM to aid in the selection of polymers as a function of temperature, brine composition and pH. A new cation exchange model that includes hydrolyzed polyacrylamide has been implemented to account for the effect of different cations in the brine on the polymer properties as a function of the degree of hydrolysis. The inaccessible pore volume model has been modified to include the exclusion of large polymer molecules from pores below a certain size in addition to the effect of polymer size on the velocity of the polymer molecules within the pores that are large enough for the polymer to enter. The new inaccessible pore volume model serves as a useful tool for selecting reservoir- compatible polymers and improving the accuracy of the simulations. Extensive high-quality lab data were used to validate the new models. Simulation cases were built to illustrate how the models can be used to upscale lab results to field scale.

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Seright, Randall Scott y Dongmei Wang. "Impact of Salinity, Hardness, Lithology, and ATBS Content on HPAM Polymer Retention for the Milne Point Polymer Flood". En SPE Western Regional Meeting. SPE, 2023. http://dx.doi.org/10.2118/212946-ms.

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Abstract At the Milne Point polymer flood (North Slope of Alaska), polymer retention is dominated by the clay, illite. Illite (and kaolinite) cause no delay in polymer propagation in Milne Point core material, but they reduce the effective polymer concentration and viscosity by a significant amount (e.g., 30%), thus reducing in efficiency of oil displacement until the full injected polymer concentration is regained (which requires several pore volumes of throughput). This work demonstrates that polymer retention on illite is not sensitive to monovalent ion concentration, but it increases significantly with increased divalent cation concentration. Incorporation of a small percentage of ATBS monomers into HPAM polymers is shown to dramatically reduce retention. Results are discussed in context with previous literature reports. Interestingly, an extensive literature review reveals that polymer retention is typically only modestly sensitive to the presence of oil. Extensive examination of literature on inaccessible pore volume suggests the parameter was commonly substantially overestimated, especially in rock/sand more permeable than 500 md (which comprises the vast majority of existing field polymer floods).

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Song, Haofeng, Pinaki Ghosh y Kishore Mohanty. "Transport of Polymers in Low Permeability Carbonate Rocks". En SPE Annual Technical Conference and Exhibition. SPE, 2021. http://dx.doi.org/10.2118/206024-ms.

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Abstract Polymer transport and retention affect oil recovery and economic feasibility of EOR processes. Most studies on polymer transport have focused on sandstones with permeabilities (k) higher than 200 mD. A limited number of studies were conducted in carbonates with k less than 100 mD and very few in the presence of residual oil. In this work, transport of four polymers with different molecular weights (MW) and functional groups are studied in Edwards Yellow outcrop cores (k<50 mD) with and without residual oil saturation (Sor). The retention of polymers was estimated by both the material balance method and the double-bank method. The polymer concentration was measured by both the total organic carbon (TOC) analyzer and the capillary tube rheology. Partially hydrolyzed acrylamide (HPAM) polymers exhibited high retention (> 150 μg/g), inaccessible pore volume (IPV) greater than 7%, and high residual resistance factor (>9). A sulfonated polyacrylamide (AN132), showed low retentions (< 20 μg/g) and low IPV. The residual resistance factor (RRF) of AN132 in the water-saturated rock was less than 2, indicating little blocking of pore throats in these tight rocks. The retention and RRF of the AN132 polymer increased in the presence of residual oil saturation due to partial blocking of the smaller pore throats available for polymer propagation in an oil-wet core.

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Informes sobre el tema "Volume de pore inaccessible"

Gantzer, Clark J., Shmuel Assouline y Stephen H. Anderson. Synchrotron CMT-measured soil physical properties influenced by soil compaction. United States Department of Agriculture, febrero de 2006. http://dx.doi.org/10.32747/2006.7587242.bard.

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Methods to quantify soil conditions of pore connectivity, tortuosity, and pore size as altered by compaction were done. Air-dry soil cores were scanned at the GeoSoilEnviroCARS sector at the Advanced Photon Source for x-ray computed microtomography of the Argonne facility. Data was collected on the APS bending magnet Sector 13. Soil sample cores 5- by 5-mm were studied. Skeletonization algorithms in the 3DMA-Rock software of Lindquist et al. were used to extract pore structure. We have numerically investigated the spatial distribution for 6 geometrical characteristics of the pore structure of repacked Hamra soil from three-dimensional synchrotron computed microtomography (CMT) computed tomographic images. We analyzed images representing cores volumes 58.3 mm³ having average porosities of 0.44, 0.35, and 0.33. Cores were packed with < 2mm and < 0.5mm sieved soil. The core samples were imaged at 9.61-mm resolution. Spatial distributions for pore path length and coordination number, pore throat size and nodal pore volume obtained. The spatial distributions were computed using a three-dimensional medial axis analysis of the void space in the image. We used a newly developed aggressive throat computation to find throat and pore partitioning for needed for higher porosity media such as soil. Results show that the coordination number distribution measured from the medial axis were reasonably fit by an exponential relation P(C)=10⁻C/C0. Data for the characteristic area, were also reasonably well fit by the relation P(A)=10⁻ᴬ/ᴬ0. Results indicates that compression preferentially affects the largest pores, reducing them in size. When compaction reduced porosity from 44% to 33%, the average pore volume reduced by 30%, and the average pore-throat area reduced by 26%. Compaction increased the shortest paths interface tortuosity by about 2%. Soil structure alterations induced by compaction using quantitative morphology show that the resolution is sufficient to discriminate soil cores. This study shows that analysis of CMT can provide information to assist in assessment of soil management to ameliorate soil compaction.

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Oliynyk, Kateryna y Matteo Ciantia. Application of a finite deformation multiplicative plasticity model with non-local hardening to the simulation of CPTu tests in a structured soil. University of Dundee, diciembre de 2021. http://dx.doi.org/10.20933/100001230.

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In this paper an isotropic hardening elastoplastic constitutive model for structured soils is applied to the simulation of a standard CPTu test in a saturated soft structured clay. To allow for the extreme deformations experienced by the soil during the penetration process, the model is formulated in a fully geometric non-linear setting, based on: i) the multiplicative decomposition of the deformation gradient into an elastic and a plastic part; and, ii) on the existence of a free energy function to define the elastic behaviour of the soil. The model is equipped with two bonding-related internal variables which provide a macroscopic description of the effects of clay structure. Suitable hardening laws are employed to describe the structure degradation associated to plastic deformations. The strain-softening associated to bond degradation usually leads to strain localization and consequent formation of shear bands, whose thickness is dependent on the characteristics of the microstructure (e.g, the average grain size). Standard local constitutive models are incapable of correctly capturing this phenomenon due to the lack of an internal length scale. To overcome this limitation, the model is framed using a non-local approach by adopting volume averaged values for the internal state variables. The size of the neighbourhood over which the averaging is performed (characteristic length) is a material constant related to the microstructure which controls the shear band thickness. This extension of the model has proven effective in regularizing the pathological mesh dependence of classical finite element solutions in the post-localization regime. The results of numerical simulations, conducted for different soil permeabilities and bond strengths, show that the model captures the development of plastic deformations induced by the advancement of the cone tip; the destructuration of the clay associated with such plastic deformations; the space and time evolution of pore water pressure as the cone tip advances. The possibility of modelling the CPTu tests in a rational and computationally efficient way opens a promising new perspective for their interpretation in geotechnical site investigations.

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Friedman, Shmuel, Jon Wraith y Dani Or. Geometrical Considerations and Interfacial Processes Affecting Electromagnetic Measurement of Soil Water Content by TDR and Remote Sensing Methods. United States Department of Agriculture, 2002. http://dx.doi.org/10.32747/2002.7580679.bard.

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Time Domain Reflectometry (TDR) and other in-situ and remote sensing dielectric methods for determining the soil water content had become standard in both research and practice in the last two decades. Limitations of existing dielectric methods in some soils, and introduction of new agricultural measurement devices or approaches based on soil dielectric properties mandate improved understanding of the relationship between the measured effective permittivity (dielectric constant) and the soil water content. Mounting evidence indicates that consideration must be given not only to the volume fractions of soil constituents, as most mixing models assume, but also to soil attributes and ambient temperature in order to reduce errors in interpreting measured effective permittivities. The major objective of the present research project was to investigate the effects of the soil geometrical attributes and interfacial processes (bound water) on the effective permittivity of the soil, and to develop a theoretical frame for improved, soil-specific effective permittivity- water content calibration curves, which are based on easily attainable soil properties. After initializing the experimental investigation of the effective permittivity - water content relationship, we realized that the first step for water content determination by the Time Domain Reflectometry (TDR) method, namely, the TDR measurement of the soil effective permittivity still requires standardization and improvement, and we also made more efforts than originally planned towards this objective. The findings of the BARD project, related to these two consequential steps involved in TDR measurement of the soil water content, are expected to improve the accuracy of soil water content determination by existing in-situ and remote sensing dielectric methods and to help evaluate new water content sensors based on soil electrical properties. A more precise water content determination is expected to result in reduced irrigation levels, a matter which is beneficial first to American and Israeli farmers, and also to hydrologists and environmentalists dealing with production and assessment of contamination hazards of this progressively more precious natural resource. The improved understanding of the way the soil geometrical attributes affect its effective permittivity is expected to contribute to our understanding and predicting capability of other, related soil transport properties such as electrical and thermal conductivity, and diffusion coefficients of solutes and gas molecules. In addition, to the originally planned research activities we also investigated other related problems and made many contributions of short and longer terms benefits. These efforts include: Developing a method and a special TDR probe for using TDR systems to determine also the soil's matric potential; Developing a methodology for utilizing the thermodielectric effect, namely, the variation of the soil's effective permittivity with temperature, to evaluate its specific surface area; Developing a simple method for characterizing particle shape by measuring the repose angle of a granular material avalanching in water; Measurements and characterization of the pore scale, saturation degree - dependent anisotropy factor for electrical and hydraulic conductivities; Studying the dielectric properties of cereal grains towards improved determination of their water content. A reliable evaluation of the soil textural attributes (e.g. the specific surface area mentioned above) and its water content is essential for intensive irrigation and fertilization processes and within extensive precision agriculture management. The findings of the present research project are expected to improve the determination of cereal grain water content by on-line dielectric methods. A precise evaluation of grain water content is essential for pricing and evaluation of drying-before-storage requirements, issues involving energy savings and commercial aspects of major economic importance to the American agriculture. The results and methodologies developed within the above mentioned side studies are expected to be beneficial to also other industrial and environmental practices requiring the water content determination and characterization of granular materials.

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Porosity, permeability, density, and pore volume compressibility data of core from the Phillips-Cherryville North Cook Inlet A-2 well. Alaska Division of Geological & Geophysical Surveys, 1989. http://dx.doi.org/10.14509/18955.

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