intrinsic permeability

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Intrinsic permeability effect on vacuum drying process of porous medium

Intrinsic permeability effect on vacuum drying process of porous medium

The moisture curve of different intrinsic permeability is shown in Figure 1.The intrinsic permeability k in = 4×10 -13 and k in = 4×10 -14 m 2 is quickly gotten the drying end time. It just is taken less than 3.5 hours and 7 hours respectively. When the k in = 4×10 -15 m 2 , the drying time is too long. It is taken more than 28 hours. But when the k in = 4×10 -15 m 2 , the drying is not gotten the end until more than 56 hours that just gotten the 0.5 d. b.. The effect of intrinsic permeability on moisture is so obviously.

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On the unintentional rarefaction effect in LBM modeling of intrinsic permeability

On the unintentional rarefaction effect in LBM modeling of intrinsic permeability

Lattice Boltzmann method (LBM) is a popular method for calculation of flow properties of porous media e.g. intrinsic permeability (Ferr´ eol and Rothman, 1995; Spaid and Phelan, 1997; Pan et al., 2006; Hosa et al., 2016; Prestininzi et al., 2016). The standard LBM is regarded as an alternative method to computational fluid dynamics (CFD), equivalent to solving the incompressible (or near incompressible) Navier- Stokes equation. Through the Chapman-Enskog expansion, we can show that the convergence of LBM to the incompressible Navier-Stokes equation in the low Mach and Knudsen num- bers limits. However, these two methods are very different. For example, the third-order and higher-order moments are completely neglected in the isothermal Navier-Stokes equation while they are still available in LBM simulations through particle distribution functions, despite that they can be negli- gibly small when the Knudsen number (Kn) is close to zero. Therefore, the high-order moments have to be negligible if the LBM simulation is correctly working at the Navier-Stokes level, which has been commonly oversighted in simulating flows in porous media.

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Determination of The Characteristic Particle Diameter of A Road Construction Soil Using Intrinsic Permeability Formula

Determination of The Characteristic Particle Diameter of A Road Construction Soil Using Intrinsic Permeability Formula

Abstract--The characteristic grain diameter of a Road construction soil (Laterite) was determined using the intrinsic permeability formula, The soil sample (laterite) was collected from Ngelzarma local government area of Yobe state. The site lies on Latitude of 11 o , 41’, 18.4” N, longitude 11°32’50.7’ and altitude of 434.0m. The particle size distribution was obtained using the dry sieve analysis method and is presented as a curve on a semi- logarithmic plot from which the modified uniformity coefficient (Ø 10 / Ø 60 ) was derived. The particles

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Evaluation of Preservation Effect by Aquo Siloxane Method towards Water Permeation and Material Diffusion into Porous Rocks

Evaluation of Preservation Effect by Aquo Siloxane Method towards Water Permeation and Material Diffusion into Porous Rocks

Various kinds of heritages, such as architectures, statues, grave posts and towers, are made by stone, and they are facing the crisis of weathering. Therefore, it is necessary to give appropriate treatments to keep them in good conditions. Kyushu Research Institute for Cultural Properties Inc. and Ku- mamoto University introduced a new method, Aquo-Siloxane Method, in or- der to protect the stone heritages. In this study, preservation effect by Aquo- Siloxane method towards water permeation and material diffusion was veri- fied. Here one-dimensional permeation and diffusion tests were conducted, and the intrinsic permeability and diffusion coefficient of rock samples with and without Aquo-Siloxane treatments were evaluated. As rock samples, 3 types of sandstones and concrete were applied. It was found that the permea- bility decreased to less than 1/10 to 1/100 of without Aquo-Siloxane treat- ment, and that the effect gradually developed during more than one year. One-dimensional diffusion tests were also conducted, and the diffusion process in rock samples are visualized by X-ray CT scanner system. It was confirmed internal structures of samples are clearly visualized, and that the diffusion process was also visualized as X-ray CT images. In order to extract the necessary information due to diffusion, image subtraction method was applied to image data. Then, by comparing obtained CT image data and nu- merical solutions, diffusion coefficients of rock samples with and without Aquo-Siloxane treatments were evaluated. As a result, diffusion coefficients also became smaller by applying Aquo-Siloxane treatments. It is revealed that material movement due to diffusion was also efficiently suppressed by apply- ing Aquo-Siloxane method. Finally, Aquo-Siloxane method was applied to a stone heritage. It was found that no more chippings and cracks were observed and that the heritage has been kept in good condition for at least four years. How to cite this paper: Sato, A., Egashira,

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Effects of Carbonation on the Microporosity and Macro Properties of Portland Cement Mortar CEM I

Effects of Carbonation on the Microporosity and Macro Properties of Portland Cement Mortar CEM I

Figure 11 presents the evolution of the gas intrinsic permeability during carbonation. Contrary to what we expected, an increase in the gas intrinsic permeability was observed. The results seem to be in conflict with the decrease of the porosity. However, the water porosity decreases after carbonation means that the totality of pores decreases, but we have no specific information about the meso and macro pores. By combination with the pore size distribution calculated from nitrogen adsorption, we have concluded that the carbonation resulted in an in- crease in the volume of mesopores at the expense of the volume of micropores. Therefore, it seems that the evo- lution of the gas permeability during carbonation is largely influenced by the changes in mesoporous domain: the increase in the volume of mesopores is the cause of the increase in the gas intrinsic permeability. The gas permeability was not influenced by the decrease in the volume of micropores.

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Lattice Boltzmann modelling of immiscible two-phase flows

Lattice Boltzmann modelling of immiscible two-phase flows

phase in structure 1 is greater ( ≈ 1.3) than in structure 2 ( ≈ 1.2). It is found that in this region the value of the surface ratios between fluid-fluid, non-wetting fluid-solid and wetting fluid-solid are similar. The surface ratio between the non-wetting fluid-solid and fluid-fluid approaches 0.015 for both structures in group 1, while it approaches a value of 0.1 in group 2. Hence, the difference in the values of the relative permeabilities between structures 1 and 2 in Fig. 5.7 are not a result of the changes between the fluid-fluid, non- wetting fluid-solid and wetting fluid-solid surface ratios. Fully connected flows of the non-wetting phase in porous structures can be treated as pipe like flows once the linear region is reached (i.e the influence of capillary pressure becomes negligible). In this case, the flow rate of the non-wetting phase increases since the effective pore size decreases due to the existence of a slip boundary caused by the film of the wetting phase covering the solid phase. This observation is in great agreement with the research conducted by Berg et al. [151] regarding pipe flows with slip at the wall. From Fig. 5.8 it can be observed that the Capillary number presents a non-linear behaviour at low driving forces in accordance with the non-wetting phase relative permeabilities. Moreover, the Capillary number versus driving forces relationship approximately collapses onto a single curve for the two structures at high levels of driving forces. However, the fact that structure 1 presents similar Capillary numbers with structure 2 in that region, is attributed to its lower intrinsic permeability, which further enhances capillary pressure effects.

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Intrinsic and apparent gas permeability of heterogeneous and anisotropic ultra-tight porous media

Intrinsic and apparent gas permeability of heterogeneous and anisotropic ultra-tight porous media

The various morphological features of the aforementioned two-di- mensional complex porous media, unambiguously affect the apparent gas permeability. Numerical results of the linearized BGK solved by the DVM reveal the relationships between the controlling parameters of the QSGS structures and the apparent permeability. Due to the high com- putational cost (Ho et al., 2019), numerical results of only four porous structures are compared across a wide range of Kn numbers. Never- theless, these simulations are adequate to demonstrate the impact of the variation of each parameter on the apparent permeability, compared to a reference case. Simulations are performed for part of the slip and transition flow regimes which are of main interest as far as shale pro- duction is concerned. In Fig. 8 the data points represent the raw data and not mean values, since only one geometry is simulated for every set of QSGS parameters. The slip-corrected permeability, obtained by fit- ting the numerical solution of the NSEs imposing a first-order velocity- slip boundary condition (FVBC) at small Knudsen numbers to the first- Fig. 6. Intrinsic permeability formulation for isotropic geometries. Fitting tortuosity with equation (9) and the permeability with equation (11).

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3-D image-based numerical computations of snow permeability: links to specific surface area, density, and microstructural anisotropy

3-D image-based numerical computations of snow permeability: links to specific surface area, density, and microstructural anisotropy

We carried out numerical estimations of the full 3-D tensor of intrinsic permeability (K) on 35 3-D images of seasonal snow obtained from microtomography. Computations were performed with the software Geodict (Thoemen et al., 2008; Koivu et al., 2009; Calonne et al., 2011) and were based on the periodic homogenization method (Auriault et al., 2009). The main objective of this paper was to elaborate a parame- terization of the snow permeability from other variables mea- surable in the field. For this purpose, we studied the relation- ship between the computed permeability, snow density and grain size, defined here as the equivalent sphere radius, at the scale of the representative elementary volume (REV). This relationship obtained using our data was compared to exist- ing literature datasets as well as other equations from theo- retical models and regressions. In addition, we focused on the anisotropy of permeability, available from the computed 3-D tensor of permeability.

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A comparative study of swimmers, runners, cyclists and triathletes  on sports motivation scale

A comparative study of swimmers, runners, cyclists and triathletes on sports motivation scale

The mean and standard deviation of the factors of sport motivation for triathletes, runners, cyclists and rs are Intrinsic motivation to know (IMTK) (24.45 ± 2.46), (23.55 ± 3.40), (20.3 ± 5.06) and (18.45 ± 2.77), Intrinsic motivation to accomplish (IMTA) (23 ± 2.78),(20.75 ± 5.15), (20.85 ± 3.89) and (18.7 ± 3.80), ion (IMTES) (22.8 ± 4.05), (23.85 ± 4.23), (20.45 ± 4.10) and (17.9 ± 3.81), Extrinsic motivation identification (EMI) (22.2 ± 4.47), (21.15 ± 4.38), (20.55 ± 4.57) and (17.7 ± 4.75), 20.3 ± 4.53) and (18.45 ± 4.21), Extrinsic motivation external regulation (EMER) (22.45 ± 3.63), (20.1 ± 5.08), (19.75 ± 5.08) and (18.15 ± 4.27) and Amotivation (AM) (21.05 ± 4.08), (22.4 ± 4.16), (20.05 ± 4.32) and (17.3 ± 3.45) respectively. The ANOVA result value of the factors of the sports motivation of the selected athletes was less than 0.05 and hence value is significant at 5 % level. Since the ANOVA results was significant so the Post hoc Comparison of using LSD Test and the results shows that there exists a significant difference in the different factors in between triathletes and cyclists ( p = .000), triathletes and swimmers (p = .000), runners and 00) in IMTK, triathletes and swimmers (p = .001) in IMTA, triathletes and swimmers (p = .000) runners and cyclists (p = .010) runners and swimmers (p = .000) and cyclists and swimmers (p = .050) in IMTES, triathletes and swimmers (p = .002) and runners and swimmers (p = .019) in EMI, triathletes and swimmers (p = .012) and runners and swimmers (p = .038) in EMIJ, triathletes and swimmers (p = .004) in EMER and triathletes and swimmers (p = .004), runners and cyclists (p = .000) and cyclists and values were less than 0.05 (p ˂ .05). This implies that in spite of similarities in nature of events there exist differences, or there are special requirements

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The permeability of composite soils

The permeability of composite soils

This study of composite soils shows that they can be either matrix dominated soils in which the fine grained component dictates the engineering behaviour or clast dominated soils in which the coarse grained component dictates the engineering behaviour. There is a transitional behaviour between matrix dominated and clast dominated behaviour which occurs at between 20% and 35% coarse grained content depending on the confining stress and type of fine grained particles. In matrix dominated soils, the permeability is controlled by the characteristics of the fine grained component. The coarse grained content has little effect on the conductivity as the particles are randomly distributed through the fine grained matrix. As the fine grained content reduces, the number of active contacts between the coarse grained particles increases, leading to an increase in the size of pores contained within the soil matrix, thus increasing the permeability. This is the transition zone where the hydraulic conductivity starts to increase. With a further reduction in fine grained content, the hydraulic conductivity of the soil continues to increase until the flow is dominated by the characteristics of the coarse grained fabric as the influence of the fine grained content on the flow of water is small and can be ignored. The soil in this zone is non-plastic.

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1-((2,4-Dichlorophenethyl)Amino)3-Phenoxypropan-2-ol Kills Pseudomonas aeruginosa through Extensive Membrane Damage

1-((2,4-Dichlorophenethyl)Amino)3-Phenoxypropan-2-ol Kills Pseudomonas aeruginosa through Extensive Membrane Damage

The ever increasing multidrug-resistance of clinically important pathogens and the lack of novel antibiotics have resulted in a true antibiotic crisis where many antibiotics are no longer effective. Further complicating the treatment of bacterial infections are antibiotic- tolerant persister cells. Besides being responsible for the recalcitrant nature of chronic infections, persister cells greatly contribute to the observed antibiotic tolerance in biofilms and even facilitate the emergence of antibiotic resistance. Evidently, eradication of these persister cells could greatly improve patient outcomes and targeting persistence may provide an alternative approach in combatting chronic infections. We recently characterized 1-((2,4-dichlorophenethyl)amino)-3-phenoxypropan-2-ol (SPI009), a novel anti-persister molecule capable of directly killing persisters from both Gram-negative and Gram-positive pathogens. SPI009 potentiates antibiotic activity in several in vitro and in vivo infection models and possesses promising anti-biofilm activity. Strikingly, SPI009 restores antibiotic sensitivity even in resistant strains. In this study, we investigated the mode of action of this novel compound using several parallel approaches. Genetic analyses and a macromolecular synthesis assays suggest that SPI009 acts by causing extensive membrane damage. This hypothesis was confirmed by liposome leakage assay and membrane permeability studies, demonstrating that SPI009 rapidly impairs the bacterial outer and inner membranes. Evaluation of SPI009-resistant mutants, which only could be generated under severe selection pressure, suggested a possible role for the MexCD-OprJ efflux pump. Overall, our results demonstrate the extensive membrane-damaging activity of SPI009 and confirm its clinical potential in the development of novel anti-persister therapies.

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Quantitative Characterization and Dynamic Law of Interlayer Interference for Multilayer Commingled Production in Heavy Oil Reservoirs by Numerical Simulation

Quantitative Characterization and Dynamic Law of Interlayer Interference for Multilayer Commingled Production in Heavy Oil Reservoirs by Numerical Simulation

All of these previous works laid a solid foundation for later research. However, these works were not focused on pseudo start pressure gradient ( PSPG ). These previous models are no longer applicable for heavier oil with PSPG . In recent years, pioneer works were conducted on the flow behaviors of heavy oil with PSPG . Wang Shoulei et al . [18] proposed a new method to determine interlayer in- terference coefficient by considering PSPG in reservoir simulation. Based on the consideration of periodicity and dynamic characteristics, Xu Jiafeng et al . [19] established the dynamic interference mathematic model of multilayer commin- gle producing for water flooding sand stone heavy oil. And the effects of such main factors as permeability, viscosity and threshold pressure gradient on inter- layer interference are revealed.

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Investigations on the Durability Parameters of Different Grades of Concrete

Investigations on the Durability Parameters of Different Grades of Concrete

The test methods selected for assessing the durability of concrete are Oxygen permeability test, Water sorptivity test, Surface water permeability test, Rapid chloride permeability test and water absorption test and the study is based on laboratory experimentation. Only three water cement ratios namely 0.35, 0.5 with constant cement content and 0.65 with three different cement contents (300, 350 and 400 kg/m 3 ) are used in this study. Commercially available 53 Grade OPC, locally available

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A Note on Intrinsic Correlation

A Note on Intrinsic Correlation

Abstract. In this note we characterize the strategic implication of intrinsic correlation, introduced by Brandenburger and Frieden- berg (2008), in the subjective correlated equilibrium setting of a complete information game. Intrinsic correlation restricts correla- tion devices to variables within the game, i.e. players’s beliefs (and higher order beliefs) about each other’s strategies, in contrast to signals or sunspots from the “outside.” The characterization is a strengthening of best-response set with an injectivity condition for a certain subset identified by an iterative procedure. We also give an iterative procedure, analogous to the iterated removals of dominated strategies, that arrives at strategies consistent with our characterization, which always exist.

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Intrinsic Prices of Risk

Intrinsic Prices of Risk

We review the nature of some well-known phenomena such as volatility smiles, convexity adjust- ments and parallel derivative markets. We propose that the market is incomplete and postulate the existence of intrinsic risks in every contingent claim as a basis for understanding these phe- nomena. In a continuous time framework, we bring together the notion of intrinsic risk and the theory of change of measures to derive a probability measure, namely risk-subjective measure, for evaluating contingent claims. This paper is a modest attempt to prove that measure of intrinsic risk is a crucial ingredient for explaining these phenomena, and in consequence proposes a new approach to pricing and hedging financial derivatives. By adapting theoretical knowledge to prac- tical applications, we show that our approach is consistent and robust, compared with the stan- dard risk-neutral approach.

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Intrinsic Gradient Networks

Intrinsic Gradient Networks

The multiplicative combination of receptive fields is also observed in the cortex between different stimulus and output modalities. Stimulus or motor-driven firing rates are multiplicatively modulated by gaze direction in the posterior parietal cortex (Andersen et al., 1985; Brotchie et al., 1995), dorsal premotor cortex (Boussaoud et al., 1998), and primary visual cortex (Trotter & Celebrini, 1999). Parietal reach region neurons responsive to the destination of a reach in eye-centered coordinates are multiplicatively modulated by initial hand position (Buneo et al., 2002). Such multiplicatively combined receptive fields are traditionally called gain fields, and can be used to perform coordinate transformations using only a linear combination of the gain field outputs (Salinas & Thier, 2000; Salinas & Abbott, 2001). While it is possible to construct intrinsic gradient networks that do not combine different input sources in a simple, multiplicative manner, it is encouraging that these prominent electrophysiological phenomena are so naturally captured by intrinsic gradient networks. The consistency of intrinsic gradient networks with gain fields also casts light on the computa- tional capabilities of intrinsic gradient networks. Gain fields facilitate efficient coordinate transfor- mations (Salinas & Abbott, 2001). While intrinsic gradient networks are derived based upon the computational requirement that the gradient be computable from the fixed point of the output func- tions, they are not subject to any direct restrictions on the computational power of the network. For instance, if we choose h k

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Mathematical Model to Predict the Permeability of Water Transport in Concrete Structure

Mathematical Model to Predict the Permeability of Water Transport in Concrete Structure

The durability of concrete structure depends on the frequent rate of migration through the dissolved constituent. Such migration is influenced by permeability. This condition in terms of concrete mixture is through a continuous network of the micro pores that exist in the matrix of the concrete mix. Other influences are through the porosity that exists in the interfacial of the gradation structure of the aggregate. This study characterized the rapid and accuracy of measuring concrete permeability in a mix, this include establishment of theoretical model that describes the influence of permeability on concrete structure. Experiments are performed using transient permeability apparatus to monitor the measure coarse aggregate fine sand and water are the micropores between this material as a component of concrete known as porosity and void ratio in the concrete structure, the influence of the permeability coefficient determine the rate of water transport in concrete of water migration in concrete mixture, the apparatus allowed a rapid and accurate measure of water migration in concrete mix.

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On Intrinsic Rotation of Bodies

On Intrinsic Rotation of Bodies

Spontaneous rotation of matter is investigated. The results provide further evidence in support of earlier indications of a wave-only reality in which the quantum energy packet exists in the form of a conjugate wave—particle doublet. It reveals that matter, be it wave or particle, is a harmonic oscillator defined with full spectrum of the usual mechanical properties of simple har- monic motion SHM. Notably, the quantum energy packet’s stress field cor- relates with radius to generate intrinsic torque, it motivates spontaneous rotation at all levels of the cosmic mass scale from the electron to the un- iverse; its atomic and natural units are ( ) 3.162 10 kg m s 25 3 2

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Investigations on the Durability Parameters of Different Grades of Concrete

Investigations on the Durability Parameters of Different Grades of Concrete

The penetration of moisture into structures can cause damage by the action of chemical containment agents transported by water; by the action of microorganisms growing in the humid environment or by the mechanical action of freezing and thawing. On the other hand, most of the penetrating water leaves the porous system by drying, which can cause shrinkage and carbonation in cementations materials. As many building materials are porous, the understanding of moisture transport in the porous system represents an important issue. The ability of concrete to withstand the penetration of liquid and oxygen can be described as the durability of concrete. The durability of concrete, can in turn, be quantified by certain characteristics of the concrete such as the porosity, absorptivity and permeability.

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A Study on the Thermal Properties Of 100% Modal Fabric

A Study on the Thermal Properties Of 100% Modal Fabric

Heat capacity: External energy required to increase temperature of a solid mass is known as the material’s heat capacity, it is defined as its ability to absorb heat energy. Heat capacity is not an intrinsic property i.e. it changes with material volume/mass. Specific heat - For comparison of different materials, heat capacity has been rationalized. Specific heat is heat capacity per unit mass. It has units as J/kg-K or Cal/kg-K. With increase of heat energy, dimensional changes may occur. Hence, two heat capacities are usually defined. Heat capacity at constant pressure, Cp, is always higher than heat capacity at constant volume; Cv. Cp is only marginally higher than Cv. Heat is absorbed through different mechanisms: lattice vibrations and electronic contribution.

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