Articoli di riviste: "Porosity Characterization"

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Jalal, Sadiq, Hamza Rehman, Shams Ul Alam e Abdul Wahid. "Estimation of Reservoir Porosity Using Seismic Post-Stack Inversion in Lower Indus Basin, Pakistan". International Journal of Economic and Environmental Geology 12, n. 2 (19 luglio 2021): 60–64. http://dx.doi.org/10.46660/ijeeg.vol12.iss2.2021.588.

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Seismic post-stack inversion is one of the best techniques for effective reservoir characterization. This studyintends to articulate the application of Model-Based Inversion (MBI) and Probabilistic Neural Networks (PNN) for theidentification of reservoir properties i.e. porosity estimation. MBI technique is applied to observe the low impedancezone at the porous reservoir formation. PNN is a geostatistical technique that transforms the impedance volume intoporosity volume. Inverted porosity is estimated to observe the spatial distribution of porosity in the Lower Goru sandreservoir beyond the well data control. The result of inverted porosity is compared with that of well-computed porosity.The estimated inverted porosity ranges from 13-13.5% which shows a correlation of 99.63% with the computed porosityof the Rehmat-02 well. The observed low impedance and high porosity cube at the targeted horizon suggest that it couldbe a probable potential sand channel. Furthermore, the results of seismic post-stack inversion and geostatistical analysisindicate a very good agreement with each other. Hence, the seismic post-stack inversion technique can effectively beapplied to estimate the reservoir properties for further prospective zones identification, volumetric estimation and futureexploration.

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Chen, Yen-Chun, Felix N. Buechi, Chrysoula Karageorgiou, Jens Eller e Thomas J. Schmidt. "Porosity, Porosity Heterogeneity and Morphology Characterization of Microporous Layers of Commercial Gdls". ECS Meeting Abstracts MA2022-02, n. 39 (9 ottobre 2022): 1375. http://dx.doi.org/10.1149/ma2022-02391375mtgabs.

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Porosity and morphology of MPLs have a remarkable influence on the performance of PEFCs. However, until now, MPL porosity is largely undetermined for all commercial gas diffusion layers and the MPLs are commonly thought of as a homogeneous layer in thickness and porosity. Many model studies are based on this picture. However, these assumptions are not evidence-based, and can lead to erroneous interpretations of MPL functions. The challenge of having realistic models of MPLs lies in the lack of descriptions of MPL properties on the representative millimeter scale, while its pore structure is on the nanometer scale. Here, we use laboratory-based, X-ray tomographic microscopy (XTM) to determine the porosity, thickness and their spatial heterogeneity of microporous layers from 15 commercial GDL materials on the operation-relevant, millimeter scale. These properties are relevant to the diffusive transport through diffusion media (cf. Fick’s law). The porosity distribution is measured by quantifying the volume fraction of a saturating liquid, n-decane, in the fully saturated MPL with a large field of view (FoV) of >10 mm2 and a voxel edge length (determining the image resolution) of 3.6 μm. With optimized X-ray quantum noise control, regional average porosity differences >4.7% can be determined with a 95% confidence level (for every 50 μm 50 μm regions). This resolution in porosity determination allows to define and quantify the degree of spatial porosity heterogeneity for every MPL—a property of MPL that was previously unclear. Together with the MPL thickness heterogeneity (related to intrusion depth), the MPLs of the 15 commercially available gas diffusion layers from the three international manufactures Freudenberg, Sigracet® and CeTech, are characterized and classified into 5 groups. Contrary to the common homogeneous assumption, the majority of characterized MPLs (especially from Sigracet® and CeTech) actually come with various degrees of porosity and thickness heterogeneity. These differences among MPLs could result in very different water management properties of the respective GDL materials. The representative descriptions of MPL porosity, porosity heterogeneity and thickness heterogeneity also provides realistic input to modeling. Figure 1

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Ishutov, Sergey, Franciszek J. Hasiuk, Chris Harding e Joseph N. Gray. "3D printing sandstone porosity models". Interpretation 3, n. 3 (1 agosto 2015): SX49—SX61. http://dx.doi.org/10.1190/int-2014-0266.1.

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The petroleum industry requires new technologies to improve the economics of exploration and production. Digital rock physics is a methodology that seeks to revolutionize reservoir characterization, an essential step in reservoir assessment, using computational methods. A combination of X-ray computed microtomography, digital pore network modeling, and 3D printing technology represents a novel workflow for transferring digital rock models into tangible samples that can be manufactured in a variety of materials and tested with standard laboratory equipment. Accurate replication of pore networks depends on the resolution of tomographic images, rock sample size, statistical algorithms for digital modeling, and the resolution of 3D printing. We performed this integrated approach on a sample of Idaho Gray Sandstone with an estimated porosity of 29% and permeability of 2200 mD. Tomographic images were collected at resolutions of 30 and [Formula: see text] per voxel. This allowed the creation of digital porosity models segmented into grains and pores. Surfaces separating pores from grains were extracted from the digital rock volume and 3D printed in plastic as upscaled tangible models. Two model types, normal (with pores as voids) and inverse (with pores as solid), allowed visualization of the geometry of the grain matrix and topology of pores, while allowing characterization of pore connectivity. The current resolution of commodity 3D printers with a plastic filament ([Formula: see text] for pore space and [Formula: see text] for grain matrix) is too low to precisely reproduce the Idaho Gray Sandstone at its original scale. However, the workflow described here also applies to advanced high-resolution 3D printers, which have been becoming more affordable with time. In summary, with its scale flexibility and fast manufacturing time, 3D printing has the potential to become a powerful tool for reservoir characterization.

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Rashapov, Rinat R., Jonathan Unno e Jeff T. Gostick. "Characterization of PEMFC Gas Diffusion Layer Porosity". Journal of The Electrochemical Society 162, n. 6 (2015): F603—F612. http://dx.doi.org/10.1149/2.0921506jes.

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Taylor, D. J., P. F. Fleig e S. L. Hietala. "Technique for characterization of thin film porosity". Thin Solid Films 332, n. 1-2 (novembre 1998): 257–61. http://dx.doi.org/10.1016/s0040-6090(98)01264-4.

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Santos, Teresa P., M. Fátima Vaz, Moisés L. Pinto e Ana P. Carvalho. "Porosity characterization of old Portuguese ceramic tiles". Construction and Building Materials 28, n. 1 (marzo 2012): 104–10. http://dx.doi.org/10.1016/j.conbuildmat.2011.08.004.

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Zhang, Shuxiao, Gaolong Lv, Shifeng Guo, Yanhui Zhang e Wei Feng. "Porosity Characterization of Thermal Barrier Coatings by Ultrasound with Genetic Algorithm Backpropagation Neural Network". Complexity 2021 (29 aprile 2021): 1–9. http://dx.doi.org/10.1155/2021/8869928.

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Porosity is considered as one of the most important indicators for the characterization of the comprehensive performance of thermal barrier coatings (TBCs). In this study, the ultrasonic technique and the artificial neural network optimized with the genetic algorithm (GA_BPNN) are combined to develop an intelligent method for automatic detection and accurate prediction of TBCs’s porosity. A series of physical models of plasma-sprayed ZrO2 coating are established with a thickness of 288 μm and porosity varying from 5.71% to 26.59%, and the ultrasonic reflection coefficient amplitude spectrum (URCAS) is constructed based on the time-domain numerical simulation signal. The characteristic features f 1 , f 2 , A max , Δ A of the URCAS, which are highly dependent on porosity, are extracted as input data to train the GA_BPNN model for predicting the unknown porosity. The average error of the prediction results is 1.45%, which suggests that the proposed method can achieve accurate detection and quantitative characterization of the porosity of TBCs with complex pore morphology.

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Nugroho, Ferry Anggoro Ardy. "Fabrication and Characterization of Supported Porous Au Nanoparticles". Jurnal Penelitian dan Pengkajian Ilmu Pendidikan: e-Saintika 9, n. 1 (9 dicembre 2024): 1–12. https://doi.org/10.36312/e-saintika.v9i1.2427.

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Porous plasmonic nanoparticles offer unique advantages for sensing and catalysis due to their high surface-to-volume ratio and localized electromagnetic field enhancements at nanoscale pores, or “hotspots.” However, current fabrication techniques, which are based on colloidal synthesis, face challenges in achieving precise control over particle size, shape, and porosity. Here, we present a robust nanofabrication method to produce supported arrays of porous Au nanoparticles with excellent dimensional and compositional control. By combining lithographically patterned AuAg alloy nanoparticles and selective dealloying via nitric acid, we achieve particle porosity without compromising particle morphology. Specifically, the method allows fabrication of supported porous nanoparticles with tunable dimension and porosity. Our approach demonstrates precise control of nanoparticle porosity by varying the initial Ag content in the alloy. Optical characterization reveals a blueshift in the extinction peak with increasing porosity, attributed to the reduced effective refractive index from intraparticle voids. Notably, a tunable shift of up to 100 nm in the plasmonic peak is observed, demonstrating the potential for fine-tuning optical properties. This study highlights the versatility of the proposed method in fabricating well-defined porous plasmonic nanoparticles and their ability to modulate optical properties through porosity control. These findings not only expand the toolkit for designing advanced plasmonic materials but also open pathways for applications in plasmon-mediated sensing, catalysis, and photonic devices.

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Abubakar, M., A. B. Aliyu e Norhayati Ahmad. "Characterization of Nigerian Clay as Porous Ceramic Material". Advanced Materials Research 845 (dicembre 2013): 256–60. http://dx.doi.org/10.4028/www.scientific.net/amr.845.256.

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Porous ceramics were produced by compaction method of Nigerian clay and cassava starch. The samples were prepared by adding an amount from 5 to 30%wt of cassava starch into the clay and sintered at temperature of 900-1300°C. The influence of cassava starch content on the bulk density and apparent porosity was studied. The result of XRD and DTA/TGA shows that the optimum sintering temperature was found to be 1300°C. The percentage porosity increased from 12.87 to 43.95% while bulk density decreased from 2.16 to 1.46g/cm3 with the increase of cassava starch from 5 to 30%wt. The effect of sintering temperature and cassava starch content improved the microstructure in terms of porosity and the thermal properties of porous clay for various applications which requires a specific porosity.

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Martins, Luiz M. R., e Thomas L. Davis. "From ocean-bottom cable seismic to porosity volume: A prestack PP and PS analysis of a turbidite reservoir, deepwater Campos Basin, Brazil". Interpretation 2, n. 2 (1 maggio 2014): SE91—SE103. http://dx.doi.org/10.1190/int-2013-0150.1.

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The Campos Basin is the best known and most productive of the Brazilian coastal basins. Turbidites are, by far, the main hydrocarbon-bearing reservoirs in the Campos Basin. Using a 4C ocean-bottom cable seismic survey, we set out to improve the reservoir characterization in a deepwater turbidite field in the Campos Basin. To achieve our goal, prestack angle gathers were derived and PP and PS inversion were performed. The inversion was used as an input to predict the petrophysical properties of the reservoir. Converting seismic reflection amplitudes into impedance profiles not only maximizes vertical resolution but also minimizes tuning effects. Mapping the porosity is extremely important in the development of hydrocarbon reservoirs. Combining seismic attributes derived from the PP and PS multicomponent data and porosity logs, we used linear multiregression and neural networking to predict porosity between the seismic attributes and porosity logs at the well locations. After estimating porosity in the well locations, those relationships were applied to the seismic attributes to generate a 3D porosity volume. The porosity volume highlighted the best reservoir facies in the reservoir. The integration of elastic impedance, shear impedance, and porosity improved the reservoir characterization.

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Tussniari, Putu Ekayani Sri, I. Gusti Agung Putra Adnyana e Made Cingah. "Characterization Porosity on Ceramic Body Stoneware Based Kalimantan Clay". BULETIN FISIKA 19, n. 1 (1 maggio 2018): 6. http://dx.doi.org/10.24843/bf.2018.v19.i01.p02.

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It has been made ceramic body stoneware using a mixture of Kalimantan clay, RRC feldspar, Belitung kaolin, Belitung quartz and Bukit Jimbaran limestone further coded BPC-1. This study aims to determine the value of dry shrinkage, the effect of sintering temperature of 900oC and 1200oC against firing shrinkage, and the influence of sintering temperature of 900oC and 1200oC against porosity in the ceramic body stoneware. Ceramic stoneware burned with a temperature variation of 900oC and 1200oC. The results show the value of dry shrinkage in ceramic stoneware of 2.9%. Stoneware ceramic firing shrinkage at a temperature of 900 oC combustion of 1.3%, and the combustion at a temperature 1200oC of 3.8%. Porosity ceramic stoneware at a temperature of 900oC combustion showed porosity of 10.5%, while the combustion at a temperature 1200oC of 5.5%. Show that the combustion temperature greatly affects the value of dry shrinkage, firing shrinkage and porosity of stoneware ceramics. The higher the combustion temperature the higher the shrinkage and the decreasing the porosity.

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Yang, Zhen Liang, Xin Bo He, Mao Wu, An Ma, Rong Jun Liu e Xuan Hui Qu. "Microstructural Characterization of Diamond/SiC Composites Fabricated by RVI". Key Engineering Materials 512-515 (giugno 2012): 1105–10. http://dx.doi.org/10.4028/www.scientific.net/kem.512-515.1105.

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Diamond/Si/C porous preform was prepared with phenolic resin, Si, Diamond and graphite. Subsequent reactive vapor infiltration (RVI) of gaseous silicon at 1600 °C for 2 h in vacuum atmosphere resulted in the formation of a compact Diamond/SiC composite. The influence factors of perform porosity were investigated, including process pressure and raw materials. Density and microstructure of Diamond/SiC composites were also discussed. The results showed that the open porosity of preform was mainly influenced by the pressing pressure. It can also be affected by the content, morphology and the particle size of diamond. The preform with open porosity higher than 20% after RVI treatment can obtain Diamond/SiC composites with high density. However, over-high porosity of the perform will cause a mass of unreacted Si exists in the composite which is unfavorable for its application. In order to reduce the content of residual Si, open porosity of preform should be no higher than 40%.

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Vukadin, Domagoj, Zoran Čogelja, Renata Vidaček e Vladislav Brkić. "Lithology and Porosity Distribution of High-Porosity Sandstone Reservoir in North Adriatic Using Machine Learning Synthetic Well Catalogue". Applied Sciences 13, n. 13 (28 giugno 2023): 7671. http://dx.doi.org/10.3390/app13137671.

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Reservoir characterization on offshore fields often faces specific challenges due to limited or unevenly distributed well data. The object of this study is the North Adriatic poorly consolidated clastic reservoir characterized by high porosity. The seismic data indicate notable differences in reservoir quality spatially. The only two wells on the field drilled the best reservoir area. Seismic data, seismic reservoir characterization, and accurate integration with scarce well data were crucial. This paper demonstrates how the application of machine learning algorithms, specifically a Deep Forward Neural Network (DFNN), and the incorporation of pseudo-well data into the reservoir characterization process can improve reservoir properties prediction. The methodology involves creating different reservoir porosity and thickness scenarios using pseudo-well data, synthetic pre-stack seismic data generation, seismic inversion, and DFNN utilization to improve porosity prediction. This study also highlights the importance of lithology discrimination in the geological model to better constrain reservoir properties distribution in the entire reservoir volume. Facies probability analysis was utilized to define interdependence between litho–fluid classes established from the well data and acoustic impedance volume. Apart from the field well data, seismic inversion results, and DFNN porosity volume as main inputs, acknowledgments from the neighboring fields also had an important role.

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Suparman, Nur Syazana, Khadijah Ahmad Alwi e Mohd Al Amin Muhamad Nor. "Preparation and Characterization of Hydrophobic Ceramic Foam". Materials Science Forum 840 (gennaio 2016): 77–81. http://dx.doi.org/10.4028/www.scientific.net/msf.840.77.

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Ceramic foam are a class of high porosity materials that are used for various applications. In this study, foam ceramic porcelain powder was produced by using polymeric sponge replication method at different solid content ranging from 30 to 50 wt. %. Properties of ceramic foam was characterized for porosity and density. Ceramic foam then grafted with methyltriethoxysilane (MTMS) at different concentration ranging from 0 to 9.0% v/v to determine hydrophobic effect and oil absorption capacity. From the results, it was found that the density of ceramic foam increased while porosity was decreased with increasing solid contents. It is clearly seen that, MTMS grafting contribute to hydrophobic effect of ceramic foam which enable repelling of water. The amount of oil absorbed by ceramic was found increased by increasing concentration of MTMS for all solid contents. As conclusion, MTMS give significant effects on hyrdophobic ceramic foam and produce good absorption capacity. The lower solid content produced better oil absorption compared to higher solid content due to presence of higher porosity.

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Nwaizu, Charles Chioma, Charles Chioma Nwaizu, Qiang Zhang, Christiana Iluno, Qiang Zhang e Christiana Iluno. "3D Pore Structure Characterization of Stored Grain Bed". Applied Engineering in Agriculture 38, n. 6 (2022): 941–50. http://dx.doi.org/10.13031/aea.15133.

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Highlights An image analysis for reconstruction of 3D pore structure within bulk grain was presented. Mathematical models for porosity and tortuosity were developed from the 3D reconstructed images. The mathematical models can be incorporated in computational model of flow through bulk grains. Abstract. An image analysis technique for reconstruction of the complex 3D pore structure within bulk grain from 2D section images was presented. The technique relies on aligning successive 2D images of cut-sections obtained from colored-wax solidified soybean grain beds, which were then subjected to image processing using ImageJ software developed by the National Institute of Health (NIH, Bethesda, Md.) for the reconstruction and visualization of different airflow paths within the bulk grain. Porosity and tortuosity values were quantified from the 3D image volume and 3D reconstructed inter-connected airflow paths to develop empirical mathematical models for predicting porosity and tortuosity as a function of compaction due to the pressure exerted by the grain depth. Results indicated that the rate of decrease in porosity was higher at the lower compaction grain depth and then gradually approached a minimum value as the compaction grain depth increased. At the top of the compacted grain, the porosity of the tested soybean bed was determined to be 0.42 and reduced to 0.34 at a compaction pressure of 14.2 kPa (equivalent to a compaction grain depth of 25 m). Tortuosity increased with the compaction pressure from 1.15 to 1.58 at a compaction pressure of 14.2 kPa (equivalent to 25 m of grain depth), or by 37.4%. Keywords: Grain bed, Image analysis, Pore structure, Porosity, Tortuosity.

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Takarini, Veni, Sianny Surya Putri Kurnia, Dede Taufik, Arief Cahyanto e Zulia Hasratiningsih. "Surface Characterization of Dental Porcelain Made from Sumatera Natural Sand". Key Engineering Materials 782 (ottobre 2018): 238–43. http://dx.doi.org/10.4028/www.scientific.net/kem.782.238.

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This research reported hardness and porosity morphology results on five different sintering temperatures as surface characterization of dental porcelain made from Sumateran natural sand mixture composition to prevent excessive wear. Porosity morphology was characterized with JEOL Scanning Electron Microscope (SEM), while the average hardness of each 5 different indented areas was performed with 1000 gr load for 15 seconds using Zwick Roell Vickers Hardness Tester. The result of this study shows that the higher sintering temperature correlates to higher hardness number. SEM analysis indicate less porosity appear in the samples sintered in higher temperature. By modifying the mixture, this study has significantly lowered the hardness number results compared to our previous research samples yielded 936,06 VHN. It can be concluded that positive correlation between higher temperature and hardness emerged from the surface characterization results of the dental porcelain made from Sumatera natural sand. In contrasts the porosity appear to be less developed in higher temperature. However, cracks and pores followed the indentation as in common ceramic products. Further improvement is needed with finding the optimum temperature of desired hardness number and predictable porosity, which resemble tooth enamel.

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Rouge,, N., C. Dubois, e C. Vermillet,. "Characterization of the Open Porosity of Brake Pads. II. Correlations Between Volume Porosity and Surface Area Porosity. Structural Modeling." Science and Engineering of Composite Materials 4, n. 4 (dicembre 1995): 215–22. http://dx.doi.org/10.1515/secm.1995.4.4.215.

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de Oliveira, Marize Varella, Anderson Camargo Moreira, Luiz Carlos Pereira, Waléria Silva de Medeiros e Carlos R. Appoloni. "Porosity Characterization of Sintered Titanium Scaffolds for Surgical Implants". Materials Science Forum 591-593 (agosto 2008): 36–41. http://dx.doi.org/10.4028/www.scientific.net/msf.591-593.36.

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Porosity and pore size are critical features for biomaterial scaffolds as they play an essential role in bone formation and bone ingrowth in vivo. Therefore, techniques for scaffolds evaluation are of great importance for their design and processing. Porous titanium has been used for grafts and implant coatings as it allows the mechanical interlocking of the pores and bone. In this study, porous titanium samples were manufactured by powder metallurgy. The porosity quantification was assessed by optical quantitative metallographic analysis, and non-destructive gamma-ray transmission and X-ray microtomography techniques, in order to compare their efficacy for porosity evaluation. Pore morphology and surface topography were characterized via scanning electron microscopy. These techniques have demonstrated to be suitable for titanium scaffolds evaluation, and micro-CT was the one that allowed the three-dimensional porosity assessment.

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Li, Pingping, Qianshen Li, Lei Li e Huayao Zou. "A New Method for Comprehensive and Quantitative Characterization of Shale Microfractures: A Case Study of the Lacustrine Shale in the Yuanba Area, Northern Sichuan Basin". Energies 16, n. 15 (28 luglio 2023): 5685. http://dx.doi.org/10.3390/en16155685.

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Microfractures can connect isolated pores within shale, significantly increasing the shale’s storage capacity and permeability, and benefiting shale gas exploitation. Therefore, the quantitative characteristics of microfractures are important parameters for shale reservoir evaluation. In this paper, taking the Jurassic Da’anzhai Member (J1z4) lacustrine shale in the Yuanba area of the northern Sichuan Basin as an example, we propose a method for comprehensive and quantitative characterization of shale microfractures that combines rock thin section (RTS) and scanning electron microscopy (SEM) observations. The different magnifications of RTSs and SEM images lead to the identification and characterization of microfractures of different scales using these two methods. RTSs are mainly used to characterize microfractures with widths larger than 10 μm, while SEM is mainly used to characterize microfractures with widths smaller than 10 μm. These techniques can be combined to comprehensively and quantitatively characterize microfractures of different scales in shale. The microfracture characterization results show that the average total porosity of the J1z4 shale is 4.46%, and the average microfracture surface porosity is 1.20% in the Yuanba area. The calculated average percentage of microfracture porosity to total porosity is 21.09%, indicating that the J1z4 shale reservoir space is dominated by pores and has the conditions for stable shale gas production and potential for shale gas exploration. However, the percentage of microfracture porosity to total porosity of shale near faults and fold zones approaches or exceeds 50%, which may lead to the loss of shale gas. The new method proposed in this study is also useful for quantitative characterization of shale microfractures in the Sichuan Basin and other basins.

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Mirmozafari, M., A. Iqbal, P. Zhang, N. Behdad, J. H. Booske e J. P. Verboncoeur. "Secondary electron yield characterization of high porosity surfaces for multipactor-free microwave components". Physics of Plasmas 29, n. 8 (agosto 2022): 082109. http://dx.doi.org/10.1063/5.0095160.

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We present secondary electron yield (SEY) characterization of high porosity surfaces for multipactor-free microwave components. We first calculate the SEYs of through porosity surfaces using Monte Carlo simulations. We demonstrate that these high porosity surfaces can be treated as homogeneous materials with low effective SEYs. We prove that a significant SEY reduction is attainable by high porosities, and above a certain porosity level, the entire effective SEY of the surface falls below unity, offering a multipactor free capability. We import the resultant SEYs into our semi-analytic approach to obtain multipactor susceptibility charts corresponding to different surface porosities. We predict the reduction of the multipactor-susceptible zone as the porosity increases and a total multipactor suppression with 0.66 through porosity level. The theoretical results were validated with multipactor experiments, and relatively good agreement was observed. Finally, we propose an alternative blind porosity approach that can offer the same multipactor suppression capabilities. The approach discussed herein can be adopted to design high-power multipactor-free microwave components.

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Li, Tingli, Zhiqian Yuan, Peng Meng e Yuguo Zhu. "Quantitative characterization and application of deep learning carbonate reservoir". Journal of Physics: Conference Series 2816, n. 1 (1 agosto 2024): 012076. http://dx.doi.org/10.1088/1742-6596/2816/1/012076.

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Abstract Quantitative reservoir characterization is an important research task in carbonate reservoir development. At present, the comprehensive evaluation of drilling, logging, seismic, and productivity testing data is usually used, which requires a large number of test data and tedious manual data collation. Deep learning technology can independently learn complex reservoir characteristics, has a strong ability for high-dimensional data structure mining, and has a strong advantage in solving complex nonlinear reservoir description problems closely related to various geological characteristics. Therefore, this paper applies deep learning technology to reservoir characterization. First, a deep neural network model is constructed, and then seven characteristic parameters such as fracture density, fracture opening, fracture porosity, matrix porosity, total porosity, effective thickness, and specific oil production index are taken as input variables. After model training and verification, the effective permeability distribution map of the reservoir in the target area can be automatically generated. The results show that the deep learning method has strong adaptability and practicability for the quantitative characterization of complex reservoirs, and provides a new way of thinking for the quantitative characterization of reservoirs.

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Liu, Wei Fu, Shuang Long Liu e Li Xin Sun. "Metamorphic Buried Hill Fracture Reservoir of Characterization and Evaluation". Applied Mechanics and Materials 522-524 (febbraio 2014): 1303–6. http://dx.doi.org/10.4028/www.scientific.net/amm.522-524.1303.

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Paleostress value, fractural porosity and fractural fractal dimension could be used to demonstrate the basement rock reservoir of buried hill in oilfields. The paleostress value determined the development of the reservoir fractures. Fractured types are recognized and fractural porosity is calculated by using bilateral logging data. Then the fractural fractal dimension is calculated by using seismic data to predict the distribution of fractured zone. Finally based on paleostress value, fractural porosity and fractural fractal dimension, fractured reservoir of buried hill is evaluated by using fuzzy mathematics.

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Broek, A. P., D. Bargeman, E. D. Sprengers e C. A. Smolders. "Characterization of Hemophan Hemodialysis Membranes by Thermoporometry". International Journal of Artificial Organs 15, n. 1 (gennaio 1992): 25–28. http://dx.doi.org/10.1177/039139889201500105.

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A new wet-state membrane characterization method, thermoporometry, was used to study the effect on membrane structure of commonly used sterilization methods for artificial kidney membranes. The porosity and pore size distribution of differently sterilized hollow fiber Hemophan hemodialysis membranes were determined. Also the effect of a glycerol treatment (before sterilization) on porosity and pore size distribution after sterilization was studied. Hemophan was found to have a pore size distribution of pores with radii between 1.5 and 12 nm. Most of the samples had a maximum pore volume at a pore radius of 2.5 nm, only the steam sterilized and non glycerol treated sample had a maximum pore volume at 1.5 nm. The porosity was found to vary between 14 and 31% and was dependent on the applied treatment

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Jung, Dawoon, Sehoon Hwang, Hyun-Jong Kim, Jae-Hee Han e Ho-Nyun Lee. "Characterization of Porous CuO Films for H2S Gas Sensors". Materials 15, n. 20 (18 ottobre 2022): 7270. http://dx.doi.org/10.3390/ma15207270.

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Using a thermal evaporator, various porous Cu films were deposited according to the deposition pressure. CuO films were formed by post heat treatment in the air. Changes in morphological and structural characteristics of films were analyzed using field-emission scanning electron microscopy (FE-SEM) and X-ray diffraction (XRD). Relative density and porosity were quantitatively calculated. CuO films with various pores ranging from 39.4 to 95.2% were successfully manufactured and were applied as gas sensors for H2S detection on interdigitated electrode (IDE) substrate. Resistance change was monitored at 325 °C and an increase in porosity of the film improved the sensor performance. The CuO-10 gas sensor with a high porosity of 95.2% showed a relatively high response (2.7) and a fast recovery time (514 s) for H2S 1.5 ppm. It is confirmed that the porosity of the CuO detection layer had a significant effect on response and recovery time.

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Schwantes, Denise, Gabriel Mateus Cubi Fonseca, Guilherme José Ramos Oliveira e Daniela Gomes Horta. "Effect of Operational Parameters and Iron Ore Tailings Properties on Filter Cake Porosity". Revista de Gestão Social e Ambiental 18, n. 12 (18 dicembre 2024): e09890. https://doi.org/10.24857/rgsa.v18n12-124.

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Objective: By evaluating operational filtration conditions, chemical, mineralogical, and particle size properties of the tailings, the study aimed to identify critical variables affecting porosity and provide predictive models for optimizing dewatering operations. Theoretical Framework: This research builds upon existing theories of solid-liquid separation and dewatering processes in mineral processing. Key references include classical works on filtration dynamics, particle size distribution, and cake porosity characterization. The study addresses gaps in literature regarding the relationship between tailings composition and filtration results. Method: The Leaf Test method was employed on 33 fresh slurry samples from the Brucutu plant to simulate industrial filtration conditions. Filtration cycle parameters such as cake formation and drying times were standardized. Porosity was calculated using Grace's equation and correlated with characterization data, including mineralogical composition, true density, and particle size. Statistical methods such as clustering, regression, and Random Forest modeling identified key predictors of porosity. Results and Discussion: The results indicated that porosity correlates strongly with silica content and certain mineralogical attributes, such as the presence of martitic hematite and quartz. Cluster analysis revealed two sample groups with distinct filtration characteristics. While operational parameters showed limited impact on porosity, the statistical models highlighted the significance of ore composition. Research Implications: This research provides a foundation for optimizing iron ore tailings filtration by identifying the key variables influencing porosity. The findings support more efficient dewatering techniques, contributing to sustainable tailings management. Further, the development of predictive models aids industrial operations in minimizing risks associated with tailings disposal. Originality/Value: This study is among the first to integrate statistical modeling and mineralogical characterization in exploring filter cake porosity. The results offer novel insights into the optimization of solid-liquid separation processes in the mining industry.

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Coşkun, Nihal Derin, Eren Işık, Ayşe Selcen Şahin, Çiğdem Börekçioğlu e Veli UZ. "Characterization Of High Porosity White Fired Ceramic Clay". Afyon Kocatepe University Journal of Sciences and Engineering 15, n. 3 (11 settembre 2015): 14–20. http://dx.doi.org/10.5578/fmbd.10439.

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Anovitz, Lawrence M., e David R. Cole. "Characterization and Analysis of Porosity and Pore Structures". Reviews in Mineralogy and Geochemistry 80, n. 1 (2015): 61–164. http://dx.doi.org/10.2138/rmg.2015.80.04.

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Doležal, Martin. "Characterization of σ-porosity via an infinite game". Fundamenta Mathematicae 216, n. 2 (2012): 109–18. http://dx.doi.org/10.4064/fm216-2-2.

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Shukla, Shantanu, David Stanier, Madhu S. Saha, Beniamin Zahiri, Mickey Tam, Jürgen Stumper e Marc Secanell. "Characterization of Inkjet Printed Electrodes with Improved Porosity". ECS Transactions 77, n. 11 (7 luglio 2017): 1453–63. http://dx.doi.org/10.1149/07711.1453ecst.

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Labrosse, A., e A. Burneau. "Characterization of porosity of ammonia catalysed alkoxysilane silica". Journal of Non-Crystalline Solids 221, n. 2-3 (dicembre 1997): 107–24. http://dx.doi.org/10.1016/s0022-3093(97)00414-6.

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31

Calo, J. M., P. J. Hall e M. Antxustegi. "Carbon porosity characterization via small angle neutron scattering". Colloids and Surfaces A: Physicochemical and Engineering Aspects 187-188 (agosto 2001): 219–32. http://dx.doi.org/10.1016/s0927-7757(01)00635-5.

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García, Ismael Gómez, Marco Bernabei e Maciej Haranczyk. "Toward Automated Tools for Characterization of Molecular Porosity". Journal of Chemical Theory and Computation 15, n. 1 (6 dicembre 2018): 787–98. http://dx.doi.org/10.1021/acs.jctc.8b00764.

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Bai, Ruonan, Alain Tinel, Abdellah Alem, Hervé Franklin e Huaqing Wang. "Ultrasonic Characterization of Water Saturated Double Porosity Media". Physics Procedia 70 (2015): 114–17. http://dx.doi.org/10.1016/j.phpro.2015.08.055.

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Sittner, F., e W. Ensinger. "Electrochemical investigation and characterization of thin-film porosity". Thin Solid Films 515, n. 11 (aprile 2007): 4559–64. http://dx.doi.org/10.1016/j.tsf.2006.11.031.

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35

Fang, Changliang, Mohd Amro, Guosheng Jiang e Hongzhi Lu. "Laboratory studies of non-marine shale porosity characterization". Journal of Natural Gas Science and Engineering 33 (luglio 2016): 1181–89. http://dx.doi.org/10.1016/j.jngse.2016.04.006.

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Stordal, Andreas S., e Dean S. Oliver. "Characterization of permeability and porosity from nanosensor observations". Advances in Water Resources 34, n. 8 (agosto 2011): 946–56. http://dx.doi.org/10.1016/j.advwatres.2011.04.015.

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Zhang, Haiyang, Hamid Abderrahmane, Mohammed Al Kobaisi e Mohamed Sassi. "Pore-Scale Characterization and PNM Simulations of Multiphase Flow in Carbonate Rocks". Energies 14, n. 21 (21 ottobre 2021): 6897. http://dx.doi.org/10.3390/en14216897.

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This paper deals with pore-scale two-phase flow simulations in carbonate rock using the pore network method (PNM). This method was used to determine the rock and flow properties of three different rock samples, such as porosity, capillary pressure, absolute permeabilities, and oil–water relative permeabilities. The pore network method was further used to determine the properties of rock matrices, such as pore size distribution, topological structure, aspect ratio, pore throat shape factor, connected porosity, total porosity, and absolute permeability. The predicted simulation for the network-connected porosity, total porosity, and absolute permeability agree well with those measured experimentally when the image resolution is appropriate to resolve the relevant pore and throat sizes. This paper also explores the effect of the wettability and fraction of oil-wet pores on relative permeabilities, both in uniform and mixed wet systems.

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Yan, W., N. Li, J. Tong, G. Liu e J. Xu. "Effect of particle size on the pore characterization and strength of porous cordierite-mullite ceramics prepared by a pore-forming in-situ technique". Science of Sintering 45, n. 2 (2013): 165–72. http://dx.doi.org/10.2298/sos1302165y.

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The porous cordierite-mullite ceramics were prepared by the pore-forming in-situ technique. The characterizations of porous cordierite-mullite ceramics were determined by an X-ray diffractometer (XRD), a scanning electron microscopy (SEM), and a microscopy measured method, etc., and the effect of particle size on phase composition, pore characterization and strength were investigated. It?s found that particle size affects strongly the formations of cordierite and mullite, and then changes the pore characterization and strength. With the decrease of the particle size, the sintering temperature at which the formations of cordierite and mullite take place extremely fast decreases, the pore size distribution becomes from bi-peak mode to mono-peak mode, the porosity and the median pore size decrease but strength increases. The most opposite mode is the specimen sintered at 1400 ?C from the grinded powder with an average particle size of 10.2 ?m, which consists of cordierite, mullite and minor spinel, and has a high apparent porosity (40 %), a high compressive strength (58.4 MPa), a small median pore size (6.3 ?m) and well-developed necks between particles.

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Bilalodin, Bilalodin, e Mukhtar Effendi. "KARAKTERISTIK FILM TIPIS TiO2 DOPING NIOBIUM". Molekul 5, n. 1 (1 maggio 2010): 10. http://dx.doi.org/10.20884/1.jm.2010.5.1.71.

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Niobium (Nb) doped Titanium dioxide (TiO2) thin films have been successfully grown using spin coating method. Characterizations of thin films was carried out using EDAX (Energy Dispersion Analysis for X-Ray), XRD (X-Ray Diffaction) and SEM (Scanning Electron Microscope) to determine the microstructure of thin films. Determination microstructure, particularly of crystal structure was examined using ICDD data, whereas porosity calculation was done using the toolbox application on Matlab 6.1 software. EDAX, XRD and SEM characterization show that the thin films grown well at the Si substrates with the (002) field orientation is dominant and the thin film has the rutile structure. The TiO2 : Nb thin films product have granules round, uniform grain size and porosity value of about 41%.

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Papa, Elettra, Elena Landi, Francesco Miccio e Valentina Medri. "K2O-Metakaolin-Based Geopolymer Foams: Production, Porosity Characterization and Permeability Test". Materials 15, n. 3 (27 gennaio 2022): 1008. http://dx.doi.org/10.3390/ma15031008.

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In this paper, four near-net shaped foams were produced via direct foaming, starting from a benchmark metakaolin-based geopolymer formulation. Hydrogen peroxide and metallic silicon were used in different amounts as blowing agents to change the porosity from meso- to ultra-macro-porosity. Foams were characterized by bulk densities ranging from 0.34 to 0.66 g cm−3, total porosity from 70% to 84%, accessible porosity from 41% to 52% and specific surface area from 47 to 94 m2 g−1. Gas permeability tests were performed, showing a correlation between the pore features and the processing methods applied. The permeability coefficients k1 (Darcian) and k2 (non-Darcian), calculated applying Forchheimer’s equation, were higher by a few orders of magnitude for the foams made using H2O2 than those made with metallic silicon, highlighting the differing flow resistance according to the interconnected porosity. The gas permeability data indicated that the different geopolymer foams, obtained via direct foaming, performed similarly to other porous materials such as granular beds, fibrous filters and gel-cast foams, indicating the possibility of their use in a broad spectrum of applications.

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Lawson, I. D., e A. O. Balogun. "Reservoir Characterization using Petrophysical Evaluation of W-Field, Onshore Niger Delta". Asian Journal of Physical and Chemical Sciences 11, n. 2 (14 aprile 2023): 9–23. http://dx.doi.org/10.9734/ajopacs/2023/v11i2197.

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Reservoir characterization of W-field, onshore Niger Delta was carried out using petrophysical evaluation of well logs. Three reservoir sand intervals (A, B, C) were identified and correlated across four wells (W1, W2, W3, W4) in W-field using the gamma ray, while the fluid identification of each reservoir was achieved using the resistivity log. The reservoir C interval was selected and utilized for petrophysical interpretation was penetrated at depths 11741-11945ft, 11933-12173ft, 11658-11847ft and 11926-12095ft across all wells respectively.The average values of gross thickness, volume of shale, effective porosity, total porosity, permeability, water saturation and hydrocarbon saturation of the delineated reservoir sand are 200.5ft for gross thickness, 18% for shale volume, 21% for effective porosity, 26% for total porosity, 1071.74mD for permeability, and 28% for water saturation and 77% for hydrocarbon saturation. Petrophysical evaluation revealed that porosity and permeability are very good to excellent in the field. The reservoir is classed as clean sands based on the high net to gross ratio (>70%) and the low shale volumes (<30%). Consequently, the low value of shale volume, low value water saturation, high value of hydrocarbon saturation and the good porosity and permeability properties of the reservoir of interest suggest economical and commercial quality and viability of the wells within this field.

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Luo, Ming Hua, Jian Er Zhou, Yong Qing Wang, De Lin Wang e Sheng Long Wang. "Preparation and Characterization of Porous Acicular Mullite Ceramics". Advanced Materials Research 412 (novembre 2011): 65–68. http://dx.doi.org/10.4028/www.scientific.net/amr.412.65.

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Acicular mullite porous ceramics were synthesis by high-temperature sintering technique. In the present work, Kaolin and industrial aluminum hydroxide were selected as raw materials, AlF3 used as catalyst. XRD and SEM were used to detect the crystal type and microstructure of prepared mullite ceramics, respectively. The influences of sintering temperature on the growth of crystal, the apparent porosity and compressive strength of the resulting porous ceramics were investigated. The results indicate when sintering temperature ranges from 1250 ~ 1400°C, much acicular mullite crystal appeared in the resulting ceramics. The apparent porosity, the compressive strength and the morphology of the mullite whisker changed obviously with the sintering temperature. When sintering temperature is 1400°C, the porous ceramics showed the maximum compressive strength of ~28 MPa and the maximum apparent porosity of ~63%.

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Cao, Yan, Qi Wu, Zhijun Jin e Rukai Zhu. "Characterization of Microstructures in Lacustrine Organic-Rich Shale Using Micro-CT Images: Qingshankou Formation in Songliao Basin". Energies 15, n. 18 (14 settembre 2022): 6712. http://dx.doi.org/10.3390/en15186712.

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In order to explore the development characteristics and influencing factors of microscale pores in lacustrine organic-rich muddy shale, this study selected five shale samples with different mineral compositions from the Qingshankou Formation in the Songliao Basin. The oil content and mineralogy of the shale samples were obtained by pyrolysis and X-ray diffraction analysis, respectively, while the porosity of the samples was computed by micro-CT imaging. Next, based on the CT images, the permeability of each sample was calculated by the Avizo software. Results showed that the continuous porosity of Qingshankou shale in the Songliao Basin was found between 0.84 and 7.79% (average 4.76%), the total porosity between 1.87 and 12.03% (average 8.28%), and the absolute permeability was calculated between 0.061 and 2.284 × 10−3 μm2. The total porosity of the samples has a good positive correlation with the continuous porosity and permeability. This means higher values of total porosity suggested better continuous porosity and permeability. Both total porosity and continuous porosity are positively correlated with the content of clay minerals. Moreover, the oil content of the samples (the S1 peak from programmed pyrolysis) exhibits a good positive correlation with the total porosity, continuous porosity, permeability, and clay mineral content. Therefore, pores that are developed by clay minerals are the main storage space for oil and flow conduits as well. Clay minerals were found to be the main controlling factor in the porosity, permeability, and the amount of oil content in the pores in the study area.

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Joshi, Shailendra, Gaurav Gupta, Mohit Sharma, Amit Telang e Taru Mahra. "Synthesis and Characterization of Stainless Steel Foam Via Powder Metallurgy Taking Acicular Urea As Space Holder". Material Science Research India 12, n. 1 (24 giugno 2015): 43–49. http://dx.doi.org/10.13005/msri/120108.

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Stainless steel foams are produced via powder metallurgy process taking acicular urea as space holder contributing porosity with 40-70 volume %. The resulting changes in microstructure of compact after each operation comprising cold compaction, pre-heating and sintering are discussed along with causes with the help of SEM micrograph. The processed foam samples using 40 % urea by volume are quite regular and acicular in shape but with increase in porosity regularity starts diminishing. It is observed that the foam samples with 40 % porosity doesn’t show any plateau stress as in aluminum foams but those with 50 % porosity (approximately 80 MPa maximum plateau stress) and 60 % porosity (approx.45MPa) shows plateau region in true stress-strain diagram during compression test due before final densification process. It is observed that with increasing porosity plateau stress decreases, since lesser force is required to densify the foam. Therefore the stainless steel foams with low porosity can be used in light weight high strength applications e.g. structures whereas with high porosity have impact energy absorbing applications e.g. damping elements in buildings or vehicles, etc.

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Kastanis, D., D. Tasis, K. Papagelis, J. Parthenios, C. Tsakiroglou e C. Galiotis. "Oxidized Multi-Walled Carbon Nanotube Film Fabrication and Characterization". Advanced Composites Letters 16, n. 6 (novembre 2007): 096369350701600. http://dx.doi.org/10.1177/096369350701600606.

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The topological and mechanical properties of carbon nanotube films prepared by different oxidized treatments have been studied. Tensile parameters have been found to be strongly correlated with topological parameters such as porosity and bundle size. It was found that low porosity films prepared from highly oxidized CNTs result in the enhancement of their mechanical properties.

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Qodriyah, N. L., M. P. Aji, S. H. Bintari e Masturi. "Characterization of porosity and permeability in Nata De Soya porous membranes with composition modifications". Journal of Physics: Conference Series 2900, n. 1 (1 novembre 2024): 012053. https://doi.org/10.1088/1742-6596/2900/1/012053.

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Abstract Nata de soya is a fermentation product derived from tofu and tempeh waste, known for its strong and stable cellulose structure. This study focuses on characterizing the porosity and permeability of nata de soya porous membranes modified with various raw material compositions. Porosity and permeability were characterized using Scanning Electron Microscopy (SEM) and fluid flow measurements. The results indicate that the composition of tofu and tempeh waste mixture (Composition A) produced membranes with the highest porosity (51%) and permeability (1.70191 × 10−9 m2). Membranes from tofu waste (Composition B) exhibited 47% porosity and permeability of 1.59554 × 10−9 m2, while membranes from tempeh waste (Composition C) showed 43% porosity and permeability of 1.27643 × 10−9 m2. This research demonstrates that variations in raw material composition and modification processes influence membranes’ porosity and permeability characteristics, contributing significantly to the development of biomass-based materials for filtration applications and supporting efforts toward more sustainable management of organic waste.

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Plucknett, Kevin P., e David S. Wilkinson. "Microstructural characterization of a microwave-sintered silicon nitride based ceramic". Journal of Materials Research 10, n. 6 (giugno 1995): 1387–96. http://dx.doi.org/10.1557/jmr.1995.1387.

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The microstructure of a microwave-densified silicon nitride based ceramic has been assessed in the as-sintered, post-sinter hot-isostatically pressed (HIPed) and annealed conditions. The grain size of the as-sintered material, which is a low substitution β′-Sialon, was significantly finer than observed in conventionally processed materials of similar composition. The as-sintered ceramic exhibits a reverse porosity gradient (with the highest porosity level at the surface) due to heat dissipation to the cooler surroundings during microwave processing. This also results in a higher β′ aspect ratio close to the surface arising from an increased glass viscosity (due to heat loss) and compositional change in this region during sintering. HIPing results in removal of all porosity from the sample core; however, a reduced porosity surface layer is retained. Significant β′-Sialon grain growth is also apparent after HIPing. A fine β′ grain structure was retained after annealing, with partial devitrification of the glassy grain boundary phase to β-Y2Si2O7.

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Jamshidi, Maryam, e Cavus Falamaki. "Image analysis method for heterogeneity and porosity characterization of biomimetic hydrogels". F1000Research 9 (15 dicembre 2020): 1461. http://dx.doi.org/10.12688/f1000research.27372.1.

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This work presents an image processing procedure for characterization of porosity and heterogeneity of fully hydrated hydrogels based on the analysis of cryogenic scanning electron microscopy (cryo-SEM) images. An algorithm consisting of different filtering, morphological transformation, and thresholding steps to denoise the image whilst emphasizing the hydrogel fibres edges for extracting the pores features is explained. Finally, the information of hydrogel porosity and heterogeneity is presented in form of pore size distribution, spatial contours maps and kernel density dot plots. The obtained results reveal that a non-parametric kernel density plot effectively determines the spatial heterogeneity and porosity of the hydrogel.

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Wang, Xiao Bei, Yuan Hua Lin e Xu Liang Deng. "Preparation and Characterization of Functional Gradient Porous ZrO₂ Ceramics". Key Engineering Materials 519 (luglio 2012): 287–90. http://dx.doi.org/10.4028/www.scientific.net/kem.519.287.

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Porous zirconium dioxide (ZrO2) ceramics has been widely used in biomedicine, heat-insulation and piezoelectric actuators. In this study, a kind of porous ZrO2 ceramics with the gradient porosity and pore sizes was designed to be a composite lamellar material. The porosity and pore size change regularly through the thickness of the layers. This porous lamellar zirconic material has been prepared by the solid state reaction consisting of yttria-stabilized zirconia (YSZ) and stearic acid (SA) powders. The porosity and pore size can be tuned by the addition of SA. The mechanical properties of the graded porous ZrO2 have been studied in detail. The results show that the mechanical characteristics of the gradient porous ZrO2 can be controlled by changing the porosity and pore size.

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Abdullah, Fathi M. S., Abdullatif A. Al-Shuhail e Oluseun A. Sanuade. "Characterization of Subsurface Cavities using Gravity and Ground Penetrating Radar". Journal of Environmental and Engineering Geophysics 24, n. 2 (giugno 2019): 265–76. http://dx.doi.org/10.2113/jeeg24.2.265.

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Subsurface cavities occur naturally by dissolution of carbonates and evaporites or by human action, such as the construction of tunnels and tombs. They can be filled with air, water, sediments, or a combination. Gravity and ground penetrating radar (GPR) methods have been used widely to determine the location and size of subsurface cavities. The objective of this study is to present a quantitative approach to estimate the porosity and water saturation of cavity-filling materials from GPR and gravity measurements. The approach uses appropriate rock-physics models of the dielectric permittivity and density of a shallow cavity and estimates the porosity and water saturation inside the cavity by solving the two model equations simultaneously for these two variables. We test the proposed method using synthetic GPR and gravity data sets corresponding to three spherical-cavity models: air-filled, water-filled, and a partially-saturated sand filling. Results show that the method is accurate in retrieving the correct porosity within 0.76% error and water saturation within 2.4% error. We also apply the method on three published case studies over air-filled rectangular cavities. We found that the proposed method estimated the correct porosity and water saturation in one study but failed with the other studies. However, when the procedure was repeated with gravity values calculated from parameters reported in these studies, the proposed method estimated the correct porosity and water saturation accurately.

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