Determination Of Porosity Research Articles

Determination of Porosity and Moisture Content of Granular Activated Carbon Using Sub-Thz Ellipsometry

Determination of Porosity and Moisture Content of Granular Activated Carbon Using Sub-Thz Ellipsometry

Assessing flow diverter porosity: a comparative analysis of quantification techniques based on imaging and simulation

ABSTRACT Background/Purpose Flow diverter porosity directly influences the blood flow reduction at the aneurysm neck level and the anatomical result of the treatment. In this research, we present and compare three methodologies to determine the local porosity of deployed flow diverters. Method Three-dimensional rotational angiography was used to obtain computational vessel models of three patients. Different flow diverters were virtually deployed in the computational models and implanted in 3D-printed models of the vasculatures by interventional neuroradiologists. Experimental porosity determinations were conducted using 2D microscope photographs and 3D Dyna-CT images (i.e. cone-beam Computed Tomography angiographic images), while simulated porosity was computed using ANKYRAS software. Results No statistically significant differences were observed between the porosity distributions from the three methods (p > 0.01). When computing the differences point-by-point, narrow distributions centered on zero were obtained, revealing a good agreement in the determinations. Orthogonal regression analysis affirmed this equivalence. The lowest agreement between porosity measurement methods was observed to occur at curve segments with relatively low porosity. Conclusions The local porosity of deployed flow diverters can be accurately determined by the three methods presented in this work. Assessing FD porosity with 3D Dyna-CT images would allow the evaluation of real patient data, whereas simulations could determine local porosity before the treatment.

A multi-step kinetics study on Chang-7 shale pyrolysis: Impact of shale inherent minerals

Pyrolysis is a significant process for the in-situ conversion and aboveground retorting of oil shale. However, the impact of inherent minerals on shale pyrolysis is still unclear. This study analyzed the effect of different inherent minerals on pyrolysis of Chang-7 oil shale, which is noted for its low carbonate, high silicate, and high pyrite content, through an integrated evaluation of kinetic and thermodynamic parameters. The pyrolysis process, arranged from 350℃ to 600℃, was deconvoluted into three distinct processes—bitumen, kerogen, and pyrite pyrolysis—using the bi-Gaussian method. Thermodynamic results showed that pyrolysis was endothermic and non-spontaneous. Minerals significantly reduced the pyrolysis activation energy. The ratio of pyrolysis activation energies for shale to kerogen increased with the carbonate-to-silicate content ratio. Master plot analysis indicated that, mineral removal shifted the reaction model from the contraction geometry model (Rn) to the diffusion model (Dn). This transition in reaction model was due to the formation of pores from demineralization and organic decomposition, facilitating the diffusion of heat and activated molecules into the interior of particles, which has been confirmed by porosity determination. This work provides an in-depth understanding of the impact of inherent minerals on shale pyrolysis, which is conducive to the efficient development and utilization of oil shale resources.

In situ determination of cement paste porosity in parallel with corrosion study of aluminium alloy 1100 in Portland cement pastes

In situ determination of cement paste porosity in parallel with corrosion study of aluminium alloy 1100 in Portland cement pastes

Carbon-binder-domain porosity extraction through lithium-ion battery electrode impedance data

In the field of 3-D resolved computational modelling of Lithium-ion battery electrodes, the arrangement and properties of the Carbon-Binder-Domain (CBD) play a critical role in the ion and electron transport properties through their impact on the electrode tortuosity factor. However, until now, the CBD porosity value -its main descriptor in terms of transport properties and occupied volume- has been determined through educated guesses due to the lack of an experimental approach. Here, a novel methodology is reported for the determination of the CBD internal porosity through the combination of computational modelling and experimental electrochemical impedance spectroscopy (EIS). The methodology is based on the creation of a calibration curve that relates tortuosity factor with CBD porosity through digital stochastic generation of electrode microstructures and diffusivity characterization. The curve is then compared to the EIS experimental results and analyzed through a transmission line model, yielding a good estimation of the parameters. In this work, the usefulness and the identified limitation of this approach are demonstrated using three different formulations of LiNi0.3Mn0.3Co0.3O2 (NMC 111) cathodes. To the best of the authors’ knowledge, this is the first reported method for estimating CBD porosity.

Freeze-casting uniformity and domains

Freeze-casting is a technique for making centimeter long microchannel structures. Freeze-cast samples are often characterized from 2D cross-sectional images, resulting in weak determination of porosity and surface area as function of height of the sample. Here we analyze a freeze-cast 40 mm long sample of ▪ (LCSM) for which we have a full X-ray tomography dataset with a voxel size of 23.34×23.34×23.34μm3, as well as a high resolution cutout with a voxel size of 2.77×2.77×2.77μm3. We analyze the porosity and tortuosity and show that the latter is 1.17 and 1.27 for the solid and pore phase respective in the direction along the microchannels, but 5.12 and 8.83 in the perpendicular direction. We also quantify the domain structure of the freeze-casted pores and show that this is not uniform for the sample, but that the angular orientation and number of domains is preserved throughout the sample.

Study of Properties of Water-Dispersion Paint and Varnish Compositions with the Content of Modified Mineral Filler

This article presents the results of research work devoted to improving the characteristics of paint and varnish coatings based on aqueous dispersions of polyacrylates; it is proposed to modify them by introducing mineral raw materials as fillers and hydrated lime, with subsequent processing in a vortex layer apparatus. The introduction of activated diatomite does not cause the deterioration of covering power, adhesion or an increase in the porosity of the paint material. The modification of coatings contributes to an increase in their operational properties, which can be associated with a reduction in the free volume in the composite and the formation of polymer boundary layers with modified physical and chemical properties. The aim of this study is to obtain a water-dispersion paint and varnish composition containing modified diatomite on a polyacrylate basis and, subsequently, study its main physical and mechanical parameters. The work has been carried out by the following method: determination of porosity, adhesion, elasticity and covering power of the control composition; determination of porosity, adhesion, elasticity and covering power of the obtained composites using modified filler; investigation of the influence of radiation on the infrared spectrum of the paint coating surface using a FLIRB620 thermal imager. As a result of this research work, it was noticed that the modification of water dispersions with silica-activated diatomite helps to eliminate the main disadvantages of materials and coatings based on acrylate binders—low water resistance and low physical and mechanical characteristics. The introduction of modified diatomite into water-emulsion paint on an acrylate base does not lead to the deterioration of the main performance characteristics of paint coatings—porosity, adhesion, elasticity and covering.

Therapeutic efficacy of Strobilanthes urticifolia-infused pectin/polyacrylic acid hydrogel for targeted hepatorenal fibrosis mitigation: A multifaceted biomaterial approach.

Pectin/polyacrylic acid (PPAA) hydrogel is a unique and versatile biomaterial with applications in drug delivery, wound healing, tissue engineering, and agriculture, owing to its tailored properties and multifunctional attributes. This study aims to harness the therapeutic potential of Strobilanthes urticifolia extract within a PPAA hydrogel matrix to attenuate liver and kidney fibrosis through targeted and sustained delivery of biologically active substances. PPAA hydrogel was prepared by free radical polymerization, followed by its porosity and swelling determination. The results depicted the porous nature of PPAA hydrogel and improved swelling properties at pH 7.4, confirming its drug delivery promise. The polyphenolic-enriched S. urticifolia extracts of leaf and flower were loaded onto PPAA hydrogel, and the loading efficiency was 87% (leaf) and 62.5% (flower). Moreover, slow-release studies showed controlled and prolonged release of polyphenols for 7 days. The polyphenolic-enriched hydrogel's microstructure was characterized using SEM, FTIR, and thermogravimetric analysis (TGA). SEM results revealed a highly porous structure of polyphenol enriched PPAA hydrogel, while FTIR analysis confirmed the presence of functional groups such as OH group of carboxylic acid, aliphatic CH2 stretching due to acrylic acid grafting with pectin, CO stretching due to acid linkage with pectin, CH of aromatic ring, and CH of carboxylate salt in PPAA hydrogel. TGA of PPAA hydrogel showed its stability up to 488°C. Additionally, the S. urticifolia extract loaded PPAA hydrogel displayed significant antibacterial properties and minimum inhibitory concentrations against both Gram-positive and Gram-negative bacteria. In vivo studies carried out on rats demonstrated that polyphenolic enriched PPAA hydrogel significantly attenuates liver and kidney fibrosis. Therefore, it is concluded from the present study that loading of polyphenolic enriched extract from leaves and flower of S. urticifolia enhanced the biomedical applications of PPAA hydrogel. RESEARCH HIGHLIGHTS: The PPAA hydrogel developed in this study exhibits a highly porous structure and improved swelling properties at physiological pH (7.4), making it an excellent candidate for drug delivery systems. S. urticifolia extracts, rich in polyphenols, were successfully incorporated into the PPAA hydrogel with high loading efficiencies of 87% for leaf and 62.5% for flower extracts. Loading of polyphenolic enriched extracts of S. urticifolia onto PPAA enhanced its biological activities such as antibacterial, hepatoprotective, and reno-protective activities as depicted by in vitro and in vivo studies.

Experimental Permeability and Porosity Determination of All-Oxide Ceramic Matrix Composite Material.

This paper presents an investigation into the water permeability of an all-oxide ceramic matrix composite. To determine the parameters and characterize the water permeability of the ceramic composite material, an experimental study was carried out in which a dedicated test rig was constructed and commissioned. A total of five different configurations of composite tubes were tested. They differed in fibre roving strength, winding angle, fibre bundle arrangement during winding, and matrix grain size distribution. To better understand the internal structure of the analysed ceramic matrix composite material, the experimental study used scanning electron microscopy for microstructure and porosity observation. The tested tubes will be used as liners in an oxy-combustion chamber in future studies. The experiments obtained new and interesting results regarding the water permeability of the ceramic matrix composite with different structural parameters. It was also observed that, as with some porous materials, the permeability of ceramic matrix composites decreases with time as more and more liquid is pressed through it.

Measurement System Analysis of Densometry Technique for the Determination of Porosity and Thickness of Porous Fuel Cell Media

Porosity is one of the critical parameters governing mass transport of reagents and products in the heterogenous architecture of a fuel cell electrode. Techniques for the measurement thereof are required that are rapid, cost-effective, and simple, and yet capable of the highest levels of accuracy, precision, and stability. This body of work presents a comprehensive account of the measurement system analysis (MSA) of the densometer technique for the ex situ determination of total porosity and mean thickness of thin film porous materials by way of hydrostatic principles. The MSA involved a four phased approach which systematically tested several process assumptions before performing gage precision and accuracy studies and, finally, benchmarking of the system against several conventional industry techniques. Results confirmed statistically that the densometry technique, in conjunction with a standardized measurement procedure, can be used for the precise and accurate measurement of porosity as well as thickness across a representative range for porous materials deployed in fuel cells and similar technologies.

Deep eutectic solvent engineered GO/ZrO2 nanofiller for mixed matrix membranes: An efficient hydrogen gas separation

AbstractThis study explores fabrication and characterization of mixed matrix membranes (MMMs) for gas separation, employing a cost‐effective solution casting method. Polycarbonate (PC) and polystyrene (PS) blends are combined with graphene oxide (GO) and zirconium dioxide (ZrO2) nanofillers, with and without a deep eutectic solvent (DES) obtained through hydrogen bond exchange. Various MMMs compositions (2–20 wt%) are systematically examined using diverse characterization techniques, including differential scanning calorimetry, thermogravimetric analysis, Fourier transform infrared spectroscopy, scanning electron microscopy, porosity determination, and water contact angle analysis. The MMMs exhibit enhanced gas permeability and selectivity, surpassing conventional membrane materials. Notably, H2 gas permeability reaches outstanding levels, with the composition PC/PS‐DES‐GO/ZrO2 at 20 wt% (PBC20‐IV) demonstrating the highest value of 86.32 Barrer. This superior performance is attributed to the unique properties of ZrO2, increased sorption capacity of GO, and enhanced thermal stability due to DES. Permeability data for CO2, N2, O2, and CH4 also show significant values, aligning with the observed trends in H2 permeability. Robeson's plot for the H2/CO2 gas pair surpasses the 2008 upper bound, placing the MMMs in a novel category for gas separation membranes. The incorporation of DES‐modified nanofiller blend composites presents a promising strategy for the potential production of pure hydrogen.

17-4 PH Steel Parts Obtained through MEX and PBF-LB/M Technologies: Comparison of the Structural Properties.

The material extrusion (MEX) method utilizing highly filled metal filament presents an alternative to advanced additive metal manufacturing technologies. This process enables the production of metal objects through deposition and sintering, which is particularly attractive compared to powder bed fusion (PBF) technologies employing lasers or high-power electron beams. PBF requires costly maintenance, skilled operators, and controlled process conditions, whereas MEX does not impose such requirements. This study compares research on 17-4 PH steel manufactured using two different commercially available techniques: MEX and powder bed fusion with laser beam melting (PBF-LB/M). This research included assessing the density of printed samples, analyzing surface roughness in two printing planes, examining microstructure including porosity and density determination, and measuring hardness. The conducted research aimed to determine the durability and quality of the obtained samples and to evaluate their strength. The research results indicated that samples produced using the PBF-LB/M technology exhibited better density and a more homogeneous structure. However, MEX samples exhibited better strength properties (hardness).

Integrating Rock Typing and Petrophysical Evaluations to Enhance Reservoir Characterization for Mishrif Formation in Garraf Oil Field

Accurate reservoir characterization is essential for successful hydrocarbon extraction, especially in complex fields such as the Garraf Oil Field. This study aims to enhance reservoir characterization by integrating different petrophysical assessments and rock typing methodologies. Density, neutron, and sonic porosity evaluations were used to assess porosity, while gamma-ray logs and resistivity measurements were used to determine shale volume. The Archie equation was employed to estimate water saturation and sensitivity analysis was used to determine the cutoff values. The study also utilized rock typing techniques, including hydraulic flow unit assessment and Rock fabric number cross-plots, to categorize reservoir rocks into flow units and identify unique rock types. The combination of these approaches led to the precise identification of reservoir heterogeneities and optimal oil production zones. The results showed that the Gamma-ray log is the best method for determining shale volume, and the closest method for porosity determination is the density log. The water resistivity value was estimated at 0.016, while the Archie parameters (a,m,n) were 1.1, 2.1, and 3.7, respectively, with cutoff values of 0.22 for shale volume, 0.11 for porosity, and 0.56 for water saturation. The study identified five rock types ranging from packstone, pack to wackstone, wackstone, wack to mudstone, and mudstone. Overall, the integration of petrophysical evaluations and rock typing techniques facilitates the accurate delineation of oil-rich zones with enhanced reservoir connectivity.

Determination of operational properties of paint coating materials

Problem. Varnishes are used in all branches of industry and economy. With their help, you can protect metals from the effects of aggressive environment, prevent from the negative effects of corrosion, preserve consumer properties, and give the treated surface an aesthetic look. One of the methods of protecting metal from corrosion is the application of coatings, including paints and varnishes, which form a protective film on the surface of the metal and prevent corrosion processes on the surface. Methodology. The research was conducted on the operational characteristics of enamel-type paint coatings: paint powder UD-1028-07040-T and soil FL-03K. Determination of moisture absorption of the free coating film was carried out using the desiccator method. In order to determine the penetration time of aggressive solutions through the paint coating film, an electrochemical method was used, whose purpose is to determine the change in the electrochemical potential of the object under study during the penetration of aggressive solutions through the paint coating film to the metal. The study of the hardness of paint coatings was carried out by the method of static indentation, respectively, using a microhardness meter. Originality. The research results showed the advantage of the UD-1028-07040-T powder paint coating over the FL-03K soil, which can be explained by such factors as the structure of the paint coating, the porosity of the surface, and the phenomenon of adhesion between the paint and the surface on which it is applied. Practical value. Powder paint UD-1028-07040-T absorbs water much less (up to 2.12%) compared to FL-03K soil (up to 5.14%), this indicates a relatively higher porosity of FL-03K soil; it is confirmed by the results of porosity determination, which was 1 point. When determining the penetration time of aggressive solutions through the paint film, it was found that FL-03K soil quickly passes aggressive solutions through its surface (in 144 hours) compared to powder paint (192 hours). This indicates that the use of powder paint in conditions involving contact with aggressive substances will be more appropriate.

Role of porosity on silica immobilized palladium complexes as recyclable catalysts in the methoxycarbonylation of 1-hexene

Immobilization of the palladium complex [Pd(L1)Cl2] (Pd1), where L1 = N,N'E,N,N'E)-N,N'-(3-(3-(triethoxysilyl)propyl)pentane-2,4-diylidene)dianiline, on MCM-41 and SBA-15 supports at 100 °C and Pd loading of 10% afforded the respective materials [Pd1@MCM-41] (Pd2) and [Pd1@SBA15] (Pd3) in moderate yields. Calcination temperatures of 150 °C and 200 °C using SBA-15 support gave the corresponding compounds Pd4 and Pd5 respectively, while using MCM-41 support and Pd loadings of 5% afforded compound Pd6. The characterization of the new materials was achieved by using FT-IR for functional group analyses, ICP-OES, TEM and SEM-EDX and XPS for surface morphology, elemental composition, particle size distribution and oxidation status respectively, PXRD for crystallinity and N2 physisorption measurements for surface area and porosity determinations. All the immobilized materials (Pd2–Pd6) formed active catalysts in the methoxycarbonylation of 1-hexene with moderate catalytic activities (TON of 372) to afford mainly linear esters. The catalytic activities of the materials depended on the nature of support and their physical properties and was largely controlled by their porosity. The SBA-15 supported catalysts, which displayed larger pore sizes, were generally more active than those of supported on MCM-41. The supported catalysts were recycled five times with minimum reduction in catalytic activities.

Determination of the porosity characteristics by pycnometric methods

Data on pore size distribution in solids are obtained by pycnometric density-based methods for measuring the pore structure of materials. The results of measuring open porosity by weighing a dry sample followed by evacuation and saturation with distilled water at atmospheric pressure, impregnation with water under pressure using a hydrostat and mercury porosimetry are presented. The samples of porous nickel obtained using powder technology by sintering of the compacts from mixtures of nickel nanopowder with powder ammonium bicarbonate NH4HCO3 (a blowing agent), the volume fractions of which were 80 and 20%, respectively, were studied. A powder blowing agent with a particle size of 63 – 125, 140 – 200, and 250 – 315 μm was used. A theoretical estimation of the pore size available for the penetration of the impregnating liquid was carried out for three methods used for the determination of open porosity. It is shown that upon water saturation after evacuation the liquid can penetrate only into pores larger than 3 μm. Moreover, in porous structures with a large fraction of submicron pores, the actual values of the open porosity are significantly underestimated when using the method of saturation with distilled water after evacuation. The higher the fraction of fine pores in the material, the lower the open porosity value. The difference between the open porosity values determined by methods of water impregnation using a hydrostat and mercury porosimetry was negligible. It has been established that among three considered methods for measuring open porosity, only the method of saturation with distilled water after evacuation cannot be used in analysis of structures with submicron pores. The results obtained can be used to develop porous functional materials and products with a given porosity structure.

Well Logs Analysis and Reservoir Evaluation of Hartha Formation in the East Baghdad oil field central Iraq

This study objective of ascertaining various petrophysical properties, which encompass volume shale, porosity, and water saturation. Well logging assumes a pivotal role in the comprehensive evaluation of reservoirs by providing measurements that can be effectively correlated with the volume fraction and composition of hydrocarbons within porous geological formations.In the course of this research, the quantification of shale volume was achieved through the utilization of gamma-ray logs, while the determination of effective porosity was facilitated by employing porosity logs, including the density log, neutron log, and sonic or acoustic log. The Hartha Formation has been stratified into distinct reservoir units based on their petrophysical characteristics. The interpretation of the findings involved the direct examination of well log readings, complemented by the application of well-established relationships and profiles to discern the critical lithological and petrophysical attributes inherent to the Hartha Formation. The selected wells from the East Baghdad oilfield, namely EB-93, EB-97, EB-51, and EB-42.

Physics-guided intelligent system for cutting force estimation in ultrasonic atomization-assisted micro-milling of porous titanium

Porous titanium is a new biomechanical implant material due to the good mechanical properties and biocompatibility. In order to meet the manufacturing needs of anisotropic porous titanium with complex micro-structures, the ultrasonic atomization with excellent cooling and lubrication effect is integrated with the micro-milling operation. Accurate prediction of cutting forces in the machining process is a principal factor as it exerts indispensable influence on the process efficiency and surface integrity. The prediction power of the traditional physics-based mechanistic cutting force model has been limited by the explicit relationship between force components and process variables based on the cutting mechanism and process geometries. In this paper, a comprehensive physics-guided intelligent system for stochastic cutting forces estimation is developed in the ultrasonic atomization-assisted micro-milling operation of porous titanium. The physics-based mechanistic cutting force model is proposed based on the determination of in-process random porosity of machined porous titanium with tool-workpiece contact. The influence of process uncertainty related to size effect and tool run-out is considered in the proposed physics-based mechanistic model. To overcome the poor nonlinear fitting and indeterminate cutting constants with numerous experiments, the machine learning algorithm has been merged into the physics-based mechanistic model to establish the physics-guided intelligent system of stochastic cutting force prediction. The predicted cutting force values of the proposed comprehensive physics-guided machine learning system are validated by the measured results with a wide variety of ultrasonic atomization-assisted micro-milling tests.

Study of the structure of fibrous composite material using computational x-ray tomography

the article discusses the determination of the actual porosity and the actual volumetric content of the reinforcing material and binder in a sample of fibrous polymer composite material (FPCM) using the non-destructive method of computational x-ray tomography. It is shown that the linear attenuation coefficient (LAC) of X-ray radiation in the volume of the sample under study based on the set of integral shadow projections obtained by X-ray transmission in various directions and its root-mean-square deviation (RMSD) provide sufficient information about the parameters of the microstructure of the sample under study. To obtain quantitative characteristics of porosity and volumetric content of components, it is necessary to examine test samples made from similar components with previously known various parameters of the material structure in the required range of scatter of these characteristics. The proposed method can be used as a non-destructive control of the structure parameters of critically important products made of VPCM, both in general and in selected local areas of the product. Also, this method is recommended for determining the actual porosity and the actual volumetric content of the binder when carrying out research work on the influence of VPCM structure parameters on the durability and residual strength of samples when exposed to external factors during operation, in particular when carrying out certification work on elementary samples.

DETERMINING THE PROPERTIES OF ROCK SAMPLES USING DEEP MACHINE LEARNING

Porosity, absolute permeability, and diffusion coefficient are crucial characteristics governing fluid flow in the porous media of geological formations. Determining these properties traditionally involves resource-intensive and time-consuming processes. However, with the advancement of deep learning methods in the last 3–4 years, artificial neural networks have gained significant traction in predicting the transport properties of the fluid-porous medium system and the geometric characteristics of porous samples based on their images. This approach allows for the rapid determination of these properties with acceptable accuracy. The aim of this article is to conduct a scientific review of literature from open sources on the deter-mination of absolute permeability, diffusion coefficient, and porosity from their images acquired through various scanning methods. Additionally, this article incorporates proprietary data, specifically images from four carbonate samples. Convolutional neural networks were examined as the method of choice.The results of this article comprise a scientific review of moderate depth regarding the effectiveness and applicability of the approach for determining important characteristics of porous media using deep machine learning methods based on sample images. In this article, we also present the results of predict-ing the open porosity of four carbonate samples based on their X-ray images using the convolutional neural network model we constructed. The conducted review has demonstrated that images (scans) of geological rock samples obtained through various scanning methods allow for the calculation of their transport properties with a high degree of accuracy using deep machine learning algorithms, and this can be achieved within a significantly short timeframe. This implies that deep machine learning can serve as a valuable alternative tool for estimating the properties of geological rock samples based on their images. The convolutional neural network model we constructed exhibited predictive capability for the porosity of three carbonate samples with a coefficient of determination ranging from 0.936 to 0.976.