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The full pore size distribution represents the integrated characteristics of micro‐nano pore‐throat systems in tight reservoirs. And it involves experiments of different scales to fully analyze the microscope properties. In this paper, we established a new approach for full pore size characterization through conducting the high‐pressure mercury intrusion (HPMI) experiments and low‐temperature nitrogen gas adsorption (LTN2GA) experiments. Meanwhile, we studied the petrology feature of the tight sandstones through X‐ray diffraction (X‐rD) and TESCAN Integrated Mineral Analyzer (TIMA). Then, we investigated the HPMI capillary pressure curves and pore size distribution characteristics, as well as the adsorption‐desorption isotherms features and BET‐specific surface area. Finally, the BJH, non‐local density functional theory (NLDFT) and the quenched solid density functional theory (QSDFT) are contrasted for analyzing the adsorption and pore size distribution characteristics. The HPMI method characterizes the macropores distribution accurately, and the micro/mesopores take up of 14.47% of the total pore spaces. The physisorption isotherms take on the combining shape of type II and IV(a), and the hysteresis loops are like type H3 combined with H4. The BET‐specific surface area is inversely proportional to permeability, and the constant of adsorption heat shows consistence with the analysis results of mineral content. QSDFT can characterize the pore size distribution of micro/mesopores more accurately than the BJH, HPMI, and NLDFT method. By combining the pores narrower than 34 nm calculated from QSDFT method and pores larger than 34 nm calculated from HPMI data with mercury intrusion pressure lower than 42.65 MPa, the full pore size distribution features of tight sandstones are accurately characterized. The micro/mesopores from the new combination method are 3.72% more than that calculated from the HPMI data, and it is of great significance for the accurate pore distribution evaluation and development of tight reservoirs. We performed low‐temperature nitrogen gas adsorption (LTN2GA), high‐pressure mercury intrusion (HPMI), and X‐ray diffraction (X‐rD) experiments on different ultra‐low permeability/tight sandstones to accurately characterize the full pore size distribution of this kind of reservoir rocks. By combining the micropore and mesopore distribution calculated by QSDFT with the mesopore and macropore distribution calculated by HPMI, the accurate characterization of full pore size distribution for the ultra‐low permeability/ tight sandstones is achieved.

In this paper, the LaAlO3 perovskite with large specific surface area and abundant surface oxygen vacancies is prepared by the hard template method, on which Ni metal nanoparticles and CaO alkaline additives are loaded. The generated catalyst is applied to the study of methane dry reforming. By analyzing and characterizing all catalysts prepared through BET, XRD, TEM, XPS, H2-TPR and other test methods, the LaAlO3 Hperovskite prepared by the hard template method can obtain both larger specific surface area and more abundant surface oxygen vacancies than the LaAlO3-C perovskite prepared by the traditional sol–gel method. As a result, the Ni-based catalysts supported by LaAlO3-H perovskite exhibit more favorable anti-sintering and anti-carbon deposition ability than Ni/LaAlO3-C catalyst. (Adding) CaO can enhance the adsorption of CO2 on Ni-based catalysts, so N-CaO/LaAlO3 catalyst possesses the most excellent anti-carbon deposition ability.

Biomass is rich, renewable, sustainable, and green resources, thereby excellent raw material for the fabrication of carbon materials. The diversity in structure and morphology of biomass are relevant in obtaining carbon materials with different structures and performances. The inherent ordered porous structure of biomass also benefits the activation process to yield porous carbons with ultrahigh specific surface area and pore volume. Besides, obtained biomass‐derived carbons (BDCs) are hard carbon with porous morphology, stable structure, superior hardness/strength, and good cycling performances when used in electrochemical capacitors (ECs). The inherent N, S, P, and O elements in biomass yield naturally self‐doped N, S, P, and O BDCs with unique intrinsic structures. In this paper, the synthesis approaches and applications of BDCs in ECs are reviewed. It shows that BDCs electrochemical performances are highly determined by their pore structures, specific surface areas, heteroatoms doping, graphitization degree, defects, and morphologies. The electrochemical performances of BDCs can further be improved by compositing with other materials, such as graphene, carbon nanofibers/nanotubes, transition metal oxides or hydroxides, and conducting polymers. The future challenges and outlooks of BDCs are also provided. Biomass‐derived carbons (BDCs) are hard carbon with porous morphology, stable structure, superior hardness/strength, and good cycling performances when used in electrochemical capacitors (ECs). In this paper, the synthesis approaches and applications of BDCs in ECs are reviewed.

The hydration of C3A-gypsum systems was studied in the presence of various types of sulfates such as gypsum, hemihydrate and Na2SO4 in the first hour. The BET method combined with a DSC analysis enabled us to quantitatively characterize the amount of precipitated ettringite and its specific surface area along the hydration. It was found that sulfates not only affected the formation rate of ettringite, but also had a significant impact on the morphology of ettringite. For all the C3A-gypsum systems, a large part of the ettringite precipitated within the first 20 min and the specific surface area of the hydrated sample strongly increased within the first 5 min, whereas the specific surface area of ettringite gradually decreased along the C3A hydration reaction. Incorporating a small amount of Na2SO4 in the C3A-gypsum system could greatly promote the formation rate of ettringite in the first 20 min, and significantly decrease the specific surface area of ettringite. As hemihydrate was added to the C3A-gypsum system, two processes of ettringite precipitation and gypsum precipitation occurred. The nucleation and growth process of ettringite and gypsum resulted in the complex changes in the specific surface area of the hydrated sample, which first increased at the very beginning, then decreased and, finally, increased.

Synthetic calcium phosphates, e.g., hydroxyapatite (HAP) and tricalcium phosphate (TCP), are the most commonly used bone-graft materials due to their high chemical similarity to the natural hydroxyapatite—the inorganic component of bones. Calcium in the form of a free ion or bound complexes plays a key role in many biological functions, including bone regeneration. This paper explores the possibility of increasing the Ca2+-ion release from HAP nanoparticles (NPs) by reducing their size. Hydroxyapatite nanoparticles were obtained through microwave hydrothermal synthesis. Particles with a specific surface area ranging from 51 m2/g to 240 m2/g and with sizes of 39, 29, 19, 11, 10, and 9 nm were used in the experiment. The structure of the nanomaterial was also studied by means of helium pycnometry, X-ray diffraction (XRD), and transmission-electron microscopy (TEM). The calcium-ion release into phosphate-buffered saline (PBS) was studied. The highest release of Ca2+ ions, i.e., 18 mg/L, was observed in HAP with a specific surface area 240 m2/g and an average nanoparticle size of 9 nm. A significant increase in Ca2+-ion release was also observed with specific surface areas of 183 m2/g and above, and with nanoparticle sizes of 11 nm and below. No substantial size dependence was observed for the larger particle sizes.

Nanoparticles (NPs) have tremendous potential for improving the stability of environmentally friendly fluorine-free firefighting foams. However, many properties of nanoparticle-stabilized foams are still unclear before application. In the present study, hydrophilic SiO 2 NPs with different specific surface area (SSA), a nonionic silicone surfactant (CoatOsil-77), and a zwitterionic hydrocarbon surfactant (BS-12) were chosen for preparing mixed dispersions in water to investigate the effect of NP SSA on fluorine-free foams. The interaction between NPs and surfactants in water, foaming ability, and foam stability of the mixed dispersions were systematically investigated. Results indicate that the conductivity and foaming ability of the mixed dispersions first decreased and then increased, whereas the dynamic viscosity and surface tension were just the reverse with increasing NP SSA. The presence of NPs with SSA of 300 or 400 m 2 /g enhanced foam stability of the mixed dispersions by delaying foam drainage and coarsening. The optimal SSA for NPs enhancing foam stability is 300 m 2 /g. The results of this study could provide theoretical guidance for the application of NPs in the development of environmentally friendly fluorine-free firefighting foams. Graphical Abstract Highlights Molecular interactions between CoatOsil-77 and BS-12 are obviously affected by addition of NPs. NPs with different SSA enhance foam stability by delaying foam drainage and coarsening. Optimal SSA for NPs to enhance foam stability of silicone and hydrocarbon surfactants is 300 m 2 /g.

g-C 3 N 4 with porous structure has been synthesized by a thermal polymerization method and its specific surface area regulated by changing the calcination temperature. The as-prepared g-C 3 N 4 was characterized by x-ray diffraction (XRD) analysis, Fourier-transform infrared (FT-IR) spectroscopy, scanning electron microscopy (SEM), transmission electron microscopy (TEM), x-ray photoelectron spectroscopy (XPS), and ultraviolet–visible (UV–Vis) spectrophotometer. The photocatalytic activity of g-C 3 N 4 was investigated using Methyl Orange (MO) as target pollutant. The results show that the g-C 3 N 4 exhibited a unique porous structure with a specific surface area reaching 142.1 m 2 /g at 610°C. When the calcination temperature was 570°C, the specific surface area of g-C 3 N 4 was 116.3 m 2 /g and the photodegradation rate of MO was 65%. Moreover, g-C 3 N 4 retained good photocatalytic stability after being used for five times. The photocatalytic mechanism was also explored by free-radical scavenging experiments.

Traditional calcium hydroxide (Ca(OH)2) typically exhibits low specific surface area and reactivity, significantly limiting its efficacy in industrial gas–solid reactions such as flue gas desulfurization and thermochemical energy storage. To address these limitations, this study proposes a two-stage synthesis strategy designed to enhance the surface properties and chemical activity of Ca(OH)2. The process involves the preparation of high-activity calcium oxide (CaO), followed by controlled hydration using diethylene glycol (DEG). Drawing on established mechanisms from cement chemistry, wherein potassium ions (K+) catalyze the decomposition of calcium carbonate (CaCO3), limestone particles (10–20 mm) were pre-soaked in a 0.1 mol/L potassium nitrate (KNO3) solution for 48 h prior to calcination. Characterization via X-ray diffraction (XRD), scanning electron microscopy (SEM), and Blaine Air Permeability Method analysis revealed that this pretreatment accelerated decomposition kinetics by inducing surface defects, yielding CaO with a maximum reactivity of 435.7 mL. Subsequent hydration at 80 °C with 70 wt% DEG effectively suppressed particle agglomeration and promoted the formation of thin platelet structures. The resulting Ca(OH)2 achieved a utilization efficiency of 98.5% and a specific surface area of 43.24 m2/g, demonstrating a robust technical route for fabricating high-performance calcium-based sorbents for environmental and energy applications.

The impact of grain size of the porous media of the 3D images of a beadpack on the permeability values and non-Darcy flow behaviour is analyzed using pore-scale flow modelling utilizing the finite volume method. In this study, the sample used was a 3D image from random tight packing of spheres (beadpack) with a size of 250×250×250 voxels and a porosity of 0.36. Variation in grain size is carried out by upscaling the 3D image sample, so that this treatment affects the specific surface area value but does not change the porosity and tortuosity of the sample. Several variations of grain diameter include 100 μm, 125 μm, 150 μm, 175 μm, and 200 μm. In this study, we adopted PIMPLE algorithm, which combines SIMPLE and PISO algorithms to accomplish the Navier-Stokes equations of fluid dynamics in such porous media. The simulation results show that the permeability value exhibits an inverse relationship with the specific surface area. This correlation is in accordance with the Kozeny-Carman equation. In addition, the initiation of non-Darcy flow occurs at the reference length-based Reynolds number of 2.06 and the permeability-based Reynolds number of 0.049.

Bentonite is one of the clay materials that have important characteristics and is applicable to construction and for different industrial uses. Treatment of this material to enhance some of its physicochemical properties to suit the desired applicability has been a focus research area. In this work, natural bentonite from Warseisso, Afar region, Ethiopia was activated with thermal treatment. The raw and treated bentonites were then characterized using SEM, FTIR, XRD, BET, and cation exchange capacity. The effects of activation parameters (time and temperature) on its physiochemical properties and its performance for the removal of sodium ions from water were investigated. Bentonite activated for 6 h at 300 °C showed a maximum specific surface area of 81.74 m2/g while the raw one showed 57.6 m2/g. However, the cation exchange capacity value of the raw bentonite was found to be 82.1 meq/100 g while the value was reduced to 67.2 meq/100 g for treated bentonite with high specific surface area. To check the performance of the activated bentonite for desalination application, batch adsorption of sodium from synthetically produced sodium chloride solution was made. A sodium removal performance of 10% was achieved with treated bentonite at the maximum specific surface area.