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Adsorption storage utilizing activated carbon is acknowledged as a promising approach for hydrogen storage duo to its high efficiency. This study compares the activated carbon adsorption storage method with the conventional empty tank storage approach. Finite element simulation is conducted to analyze the hydrogen charging process. Results reveal that under conditions with an initial temperature of 281 K and a storage pressure of 50 MPa, the adsorption tank exhibits a higher system volumetric capacity compared to the empty tank, with an increase of 12.6%. Furthermore, the influence of activated carbon's macroporosity and adsorption performance on storage capacity is investigated. It is indicated that increasing macroporosity effectively enhances storage capacity. Additionally, a comparison between the hydrogen storage performance of AX-21 activated carbon and carbon nanotubes (CNTs) highlights the significant impact of adsorption performance of the adsorbent materials on the storage capacity and temperature distribution. [Display omitted] • The adsorption tank has a 12.6% higher system volumetric capacity compared to the empty tank. • The maximum temperature in the adsorption tank is lower than that in the empty tank. • The hydrogen storage capacity in the adsorption tank increases with the increase in the macroporosity of activated carbon. • The hydrogen storage capacity of the AX-21 adsorption tank is 50% higher than that of the CNTs adsorption tank. [ABSTRACT FROM AUTHOR]

Functional refractory remains critical due to its intrinsic properties such as: saving space, lightweight and excellent thermal stability to achieve the trade-off between insulating and overall performances. The present study deals with the production of low carbon footprint and lightweight refractory matrices, with controllable pores structures, thermally stable and having low thermal conductivities. The lightweight refractory products were obtained through the direct foaming of geopolymer pastes and sintered from 900 to 1200 °C. The mechanism of pores formation, pores structures and the effect of both sintering temperature and foaming agent ratio on the thermal insulation, physical and microstructural characteristics were evaluated. The results showed that the produced matrices could be described as low thermal conductors, with thermal conductivity values between 0.49 and 0.18 W/mK. The 3D internal pore structures under laser microscopy observations confirms the mechanism of pore enlargement when high concentration of the foaming agent was added. Furthermore, the decomposition of kyanite particles within the matrices, at high temperature, favoured the extend reduction in porosity and the limitation of the liquid phase, by ensuring the formation of macro-porosities sized between 360 μm and 2 mm. The formation of the refractory crystalline phases namely: cordierite, mullite, enstatite, leucite, as well as, kalsilite, acting as filler, ensure thermal stability of the matrices. The produced materials provide an energy-saving, lightweight ceramic foams with high-strength and low thermal conductivities, potential candidates for refractory applications. [ABSTRACT FROM AUTHOR]

Increasing pasture biomass production through nitrogen fertilization enables greater stocking rate and grazing intensification in pastoral livestock production systems. However, grazing intensification can compromise the soil physical quality if stocking rates exceed the soil bearing capacity to support treading. The objective was to quantify the impact of long-term (12 years) intensified grazing of Panicum maximum Jacq. cv. IPR-86 Milênio on the physical quality of a sandy soil (Luvisol Ferric soil) under subtropical climate. The 12-year field experiment was arranged in a completely randomized split-plot design with four replicates. The approach for moving the animals in and out of the paddocks varied across harvests. In the first five harvests, the period of use and rest was fixed with each paddock being occupied for 5 days followed by 35 days of rest (i.e., 40-day grazing cycle). In the subsequent harvests, the timing for moving animals in and out of each paddock was based on pasture height, with entry set at 0.90 m and exit at 0.40 m. Grazing intensification levels (IL) consisted of different animal stocking rates, grazing cycles, and forage biomass, which varied depending on the nitrogen application doses: 0 (IL-0), 150 (IL-150), 300 (IL-300), and 450 (IL-450) kg of N ha−1 year−1. Undisturbed soil samples were taken at four depths (0–0.10, 0.10–0.20, 0.20–0.30, and 0.30–0.40 m) in two sampling positions (under plants vs. between plants) and used to measure several soil physical properties (e.g., bulk density, macroporosity, mesoporosity, microporosity, water and air storage capacity, available water, pore size distribution, and water retention curve). The impact of grazing intensification on soil physical quality was minor, occurring only between plants and at the 0–0.10 m depth, where an increase in soil bulk density and a decrease in microporosity was observed. Grazing intensification also increased the water retention capacity between plants. Regardless of the sampling position and the grazing IL, water and air storage capacity was not detrimental to plant development. Overall, the increased animal stocking rate resulting from the greater pasture biomass production due to improved nitrogen fertilization does not degrade soil physical quality. [Display omitted] • Soil physical properties were measured under different grazing intensities. • Grazing intensification impact was minimal and limited to the topsoil. • Plant available water was not compromised by intensification of grazing. • Increased forage production enabled intensified grazing without soil degradation. [ABSTRACT FROM AUTHOR]

[Display omitted] • Macroporous Ni/Al 2 O 3 catalysts are employed for dry reforming of methane (DRM). • Geometrical effect of the macroporous Al 2 O 3 structure promotes NiAl 2 O 4 formation. • Ni exsolution from NiAl 2 O 4 in H 2 reduction results in highly dispersed Ni nanocluster. • The macroporous Ni/Al 2 O 3 catalysts significantly enhance their catalytic performance in DRM. • Coke formation is strongly inhibited over macroporous Ni/Al 2 O 3 catalysts in DRM. This study aimed to investigate the geometrical effect of macroporosity on the performance of Ni-based catalysts in the dry reforming of methane (DRM). For this, macroporous Ni/Al 2 O 3 catalysts with different Ni contents were synthesized. Characterization experiments on the macroporous Ni/Al 2 O 3 catalysts revealed that the macroporous Al 2 O 3 structure enhanced NiAl 2 O 4 formation by facilitating efficient interactions between the Ni species and accessible Al 2 O 3 sites on the macroporous wall surface during calcination. In a subsequent reduction step, Ni exsolution from the NiAl 2 O 4 structure generated highly dispersed Ni nanoclusters over the macroporous Al 2 O 3. Conversely, non-macroporous Ni/Al 2 O 3 catalysts presented substantial amounts of large isolated Ni nanoparticles at an Ni content of 20 wt%, owing to limited NiAl 2 O 4 formation caused by the lack of accessible Al 2 O 3 sites. The highly dispersed Ni nanoclusters surrounded by oxygen vacancies on the macroporous Ni/Al 2 O 3 catalysts significantly enhanced their catalytic performance in the DRM, evidenced by their high CO 2 and CH 4 conversions and strong resistance to coking. Moreover, the superior coke resistance ability of the macroporous Ni/Al 2 O 3 catalysts was attributed to the gasification of the coke precursor on Ni nanoclusters surrounded by oxygen vacancies during the DRM. [ABSTRACT FROM AUTHOR]

Synthetic calcium phosphate (CaP) ceramics represent the most widely used biomaterials for bone regenerative treatments due to their biological performance that is characterized by bioactivity and osteoconductive properties. From a clinical perspective, injectable CaP cements (CPCs) are highly appealing, as CPCs can be applied using minimally invasive surgery and can be molded to optimally fill irregular bone defects. Such CPCs are prepared from a powder and a liquid component, which upon mixing form a paste that can be injected into a bone defect and hardens in situ within an appropriate clinical time window. However, a major drawback of CPCs is their poor degradability. Ideally, CPCs should degrade at a suitable pace to allow for concomitant new bone to form. To overcome this shortcoming, control over CPC degradation has been explored using multiple approaches that introduce macroporosity within CPCs. This strategy enables faster degradation of CPC by increasing the surface area available to interact with the biological surroundings, leading to accelerated new bone formation. For a comprehensive overview of the path to degradable CPCs, this review presents the experimental procedures followed for their development with specific emphasis on (bio)material properties and biological performance in pre-clinical bone defect models. Image, graphical abstract [ABSTRACT FROM AUTHOR]

Soil structure has a huge impact on plant root growth, but it is difficult to isolate from other soil properties in field studies, and generally overlooked in laboratory studies that use sieved and homogenised repacked soil. This study aimed to compare root and shoot growth under controlled soil conditions where only soil structure varied. Soil treatments used soil sieved to < 2 mm, packed in uniform layers to create a homogenous structure. A heterogeneous structure was packed from artificially formed aggregates created by breaking apart the homogeneous soil after intense compaction. Barley, peas and Arabidopsis, selected for contrasting root sizes, were grown under three levels of compaction (1.25 g cm−3, 1.40 g cm−3, 1.55 g cm−3) in both homogeneous and heterogeneous structured soils for 10 days. Penetration resistance increased from about 0.4 MPa at 1.25 g cm−3 to 1.3 MPa at 1.55 g cm−3 for either soil structure. Soil structure was quantified from water retention characteristics and X-ray Computed Tomography (CT) as complementary methods to assess the soil's pore size distribution and properties. Heterogenous soil had 50% more macropores at 1.55 g cm−3 when compared to homogenous soils. Pore structure complexity in the heterogeneous structure was found to be beneficial for root growth of peas and barley but not Arabidopsis. Shoot biomass of peas grown in heterogeneous soil at 1.55 g cm−3 increased by 65% when compared to homogenous soil, whereas barley and Arabidopsis shoot biomass did not differ significantly between any treatments. Chlorophyll, flavonoid, and nitrogen content could only be measured on barley or peas due to shoot size, but only minor differences were observed between soil structures. Soil structural heterogeneity influenced many root properties and above-ground biomass, with impacts found to be species-dependent and likely caused by the interaction between root size and preferential growth in macropores. [Display omitted] • Controlled approach to create soil structural heterogeneity. • The method uses artificial soil aggregates to create a complex pore structure. • At same bulk density soil structure influences root growth and above-ground biomass. • Impacts of soil structure heterogeneity found to be species-dependent. • Suitable to study the effects of soil physical properties on root growth. [ABSTRACT FROM AUTHOR]

• CaCO 3 as cementing agent dominates soil aggregation in loess used for reclamation. • SOC is dominantly stored in large aggregates in reclaimed soils. • N is a limiting factor for development of the microbial community. • Crop residues are not sufficient to build up SOM content. After reclamation of open-cast mining pits, soil formation starts from the deposited calcareous loess characterised by its basic physical and chemical properties whereas soil biology and structure need to develop to achieve a fully functional soil. In this study we used a chronosequence approach to elucidate soil formation on agriculturally reclaimed loess soils in an open-cast lignite mining area in Garzweiler (Germany). We selected six fields aged 0, 1, 3, 6, 12, and 24 years after the first seeding in order to observe the initial stage of development of soil properties and assess the role of management with conventional crop rotation in soil structure formation and soil organic carbon (SOC) accumulation. Loess parent material had a strong impact on aggregation, as CaCO 3 acted as a strong cementing agent. Alfalfa cultivation in the pioneering phase was of high importance in the development of microbial biomass, as it protects microbes from N limitation. Soil macroporosity and pore connectivity increased only after compost application and ploughing during agricultural crop rotation. Soil organic matter (SOM) build-up was strongly dependent on the addition of compost, as crop residues from conventional crop rotation are not sufficient to maintain high SOC contents. [ABSTRACT FROM AUTHOR]

Highlights • Controlled traffic results in more favorable physical properties to plants. • Controlled traffic condenses the compaction to the inter-row center. • Greater root dry biomass was obtained when used in controlled traffic. • Controlled traffic generates increased sugarcane yield. Abstract The mechanized sugarcane harvesting using larger and heavier machines has accentuated soil compaction. The aim of this study was to quantify the impact of harvesting controlled traffic in sugarcane cultivated under different row spacing on physical-mechanical soil attributes, root system, and yield. The experiment was carried out in an Oxisol at Nova Europa county, São Paulo state, Southeastern Brazil, with three treatments: sugarcane cultivated with single-row spacing of 1.50 m and mechanized harvesting with no and with controlled traffic management (SR and SRCT, respectively) and sugarcane cultivated with double-combined row spacing of 1.50 × 0.90 m, and mechanized harvesting with controlled traffic management (DRCT). Soil samples were taken at the planting row (R), under the wheels track of the machinery (IRC) as well as in at mid-distance between the plant row and the traffic region, identified as seedbed (S), at the depths of: 0.00–0.10, 0.10–0.20, 0.20–0.30, 0.30–0.40, 0.40–0.50, 0.50–0.70, and 0.70–1.00 m. The following soil physical attributes were assessed: bulk density, soil porosity, and soil penetration resistance, in addition to the measure biometric variables of stalk diameter, plant height and yield. Root parameters were assessed only after the 2015/2016 harvest. Controlled traffic provided more favorable soil physical properties to plant growth as expressed by lower bulk density and higher soil macroporosity both in the planting row and seedbed. Regardless of the treatment, differences were found in the soil physical properties among the sampling sites R, IRC, and S. For SRCT, an increase of 17.9% root dry biomass has been found while an increase of 18.5% occurred for the DRCT treatment as well as higher density, length, volume, and root area compared to controlled traffic absence. Controlled traffic enabled sugarcane yield gains of 8.2 and 10.3 Mg ha−1 for SRCT in the third and fourth harvests, and 18.8 and 15.7 Mg ha−1 for DRCT in the same harvest sequence. These findings suggest that controlled traffic through automatic steering associated to double row spacing minimizes soil compaction and preserves soil physical conditions for roots as well as increases sugarcane yield. [ABSTRACT FROM AUTHOR]

Abstract Zero-tillage (ZT) is being increasingly adopted globally as a conservationist management system due to the environmental and agronomic benefits it provides. However, there remains little information on the tillage effect on soil pore characteristics such as shape, size and distribution, which in turn affect soil physical, chemical and biological processes. X-ray micro Computed Tomography (μCT) facilitates a non-destructive method to assess soil structural properties in three-dimensions. We used X-ray μCT at a resolution of 70 μm to assess and calculate the shape, size and connectivity of the pore network in undisturbed soil samples collected from a long-term experiment (~30 years) under zero tillage (ZT) and conventional tillage (CT) systems in Botucatu, Southeastern Brazil. In both systems, a single, large pore (>1000 mm3) typically contributed to a large proportion of macroporosity, 91% in CT and 97% in ZT. Macroporosity was higher in ZT (19.7%) compared to CT (14.3%). However the average number of pores was almost twice in CT than ZT. The largest contribution in both treatments was from very complex shaped pores, followed by triaxial and acircular shaped. Pore connectivity analysis indicated that the soil under ZT was more connected that the soil under CT. Soil under CT had larger values of tortuosity than ZT in line with the connectivity results. The results from this study indicate that long-term adoption of ZT leads to higher macroporosity and connectivity of pores which is likely to have positive implications for nutrient cycling, root growth, soil gas fluxes and water dynamics. Highlights • Soil macro-porosity was higher under zero-tillage than conventional tillage. • Conventional tillage increases the number of pores but decreases the connectivity between them. • Zero-tillage presented lower values of pore tortuosity, indicating better connectivity. • Long term zero tillage improves soil pore connectivity. • 3D analyses of pore shape indicated difference between tillage systems. [ABSTRACT FROM AUTHOR]

Merchant vessels' performance on brash ice plays an important role in navigation in fast ice conditions in Northern Baltic ports. Among many parameters, the piece size distribution and macroporosity of the brash ice influence the accuracy of the model simulations of ship performance in brash ice. These properties also govern the brash ice accumulation and consolidation in ship channels. The current work presents analyses of macroporosity and piece size distribution from three full-scale brash ice channels investigated during winters 2020–21 and 2021–22. The results provide insights into brash ice macroporosity and piece size distribution. Smaller brash ice pieces exhibited higher porosity. On each measured cross-section, the average macroporosity ranged from 1.4% to 23%, with standard deviations of 3.8% and 16%, respectively. Porosity variations were observed in relation to equivalent brash ice thickness, the number of ship passages, and cumulative freezing air temperatures. Total porosity and the channel's brash ice porosity initially increased with breaking events and then stabilized at approximately 23% and 30%, respectively, after 9 passages. In contrast, side ridge porosity increased initially (up to 23%) and subsequently decreased. The initial total, brash ice and side ridge maximal porosities after the breaking event were estimated equal to 25%, 35% and 30%, respectively. The first two channels, which were navigated a total of 9 and 10 times, had an average degree of brash ice consolidation equal to 0.84 and 0.76, and an average degree of side ridge consolidation equal to 1.1 and 1.0, respectively. The third channel, characterized by frequent navigation, exhibited a consolidation degree of 0.82 for brash ice and 1.35 in the side ridges. The average vertical piece size across all cross-sections ranged from 0.28 m to 0.52 m with standard deviations of 0.16 m and 0.25 m. The average horizontal piece size ranged from 0.33 m to 0.4 m with standard deviations between 0.2 m and 0.34 m. The horizontal piece size distribution of brash ice was best described by the probability density function of a three-parameter lognormal distribution. • In the two less frequently navigated channels, the average porosities ranged from 1.4% to 23%. • The more frequently navigated channel exhibited average porosities ranging from 8% to 21%. • Total, brash ice, and side ridge porosities increased with increasing the corresponding thicknesses. • Brash ice piece sizes ranged from 0.06 to 1.9 m, with average vertical and horizontal sizes up to 0.52 and 0.40 m. • The distribution of horizontal piece sizes followed a three-parameter lognormal probability density function. [ABSTRACT FROM AUTHOR]

Abstract Society is becoming aware of the environment and progressively using more recycled aggregates to produce recycled structural aggregate concrete. In addition, many researches have analysed the properties of hardened recycled aggregate concrete, but few of them have focused on the mixing method and the consequences that it has on the properties of concrete. In this research, recycled aggregate concrete using dry, with extra water supply, and saturated recycled aggregate has been prepared. The different mixing conditions induce differences the micro and macroporosity of concrete that have been evaluated by computerized axial tomography, scanning electron microscopy and a new developed methodology, based on digital image analysis, developed to analyse the distribution and size of macroporosity. The software has been implemented in Matlab© and is available to the readers of the journal for downloading and use. The results show that the dry and saturated recycled aggregate lead to very different concrete properties. On the one hand, the use of dry aggregate causes a local reduction of the w/c ratio, increasing heterogeneity and decreasing workability. On the other hand, the saturated aggregate incorporates extra water by adsorption that causes an increase in the water/cement ratio, thus increasing the porosity volume and size of the new mortar of the recycled aggregate concrete. [ABSTRACT FROM AUTHOR]

There is a long-lasting debate about the effects of tillage practices on soil structure and structure-mediated ecosystem properties like hydraulic conductivity and crop productivity. This is investigated in a long-term field experiment on tillage practices at the Westerfeld trial in Bernburg, Germany (25 years of different management). Here we combine soil structure information obtained by X-ray microtomography with bulk properties like bulk density, air capacity and saturated hydraulic conductivity, as well as integrative, ecological properties like earthworm abundance and crop yield. This study goes beyond previous studies in that the soil microstructure is investigated in two different depths, within (13–23 cm) and underneath (28–38 cm) the plow horizon. Furthermore the microstructure is investigated at two different resolutions (60 μm and 20 μm) by employing a nested sampling design. The plowed horizon in the conventional tillage plots differs from the undisturbed soil underneath the cultivator depth (13–23 cm) in the reduced tillage plot by lower bulk density, higher air capacity, higher saturated hydraulic conductivity, higher macroporosity and pore connectivity. After 25 years of reduced tillage saturated hydraulic conductivity only marginally recovered in the abandoned plow pan (28–38 cm). Macropore density and connectivity did not change significantly as compared to the current plow pan under conventional tillage. The topsoil underneath the cultivator depth in the reduced tillage plot developed a “no-till pan”, as porosity and pore connectivity where smaller than in greater soil depths. Image-based macroporosity and laboratory-based air capacity showed good agreement. Overall, the combination of hydraulic measurements and X-ray CT imaging of soil microstructure at different resolutions provides a comprehensive view on soil structure modification by tillage practices. The change from conventional to reduced tillage led to a compaction of soil that was not compensated by higher bioturbation as reported for other sites. This is explained by unfavorable conditions for anecic earthworms (frequent dry periods with severely impaired penetrability of the loess substrate) as well as the absence of very deep rooting, perennial crops in crop rotation. [ABSTRACT FROM AUTHOR]

Graphical abstract Abstract This study investigated the effects of incorporating glucose microparticles (GMPs) and poly(lactic-co-glycolic acid) microparticles (PLGA MPs) within a calcium phosphate cement on the cement’s handling, physicochemical properties, and the respective pore formation. Composites were fabricated with two different weight fractions of GMPs (10 and 20 wt%) and two different weight fractions of PLGA MPs (10 and 20 wt%). Samples were assayed for porosity, pore morphology, and compressive mechanical properties. An in vitro degradation study was also conducted. Samples were exposed to a physiological solution for 3 days, 4 wks, and 8 wks in order to understand how the inclusion of GMPs and PLGA MPs affects the composite’s porosity and mass loss over time. GMPs and PLGA MPs were both successfully incorporated within the composites and all formulations showed an initial setting time that is appropriate for clinical applications. Through a main effects analysis, we observed that the incorporation of GMPs had a significant effect on the overall porosity, mean pore size, mode pore size, and in vitro degradation rate of PLGA MPs as early as after 3 days (p < 0.05). After 4 wks and 8 wks, these same properties were affected by the inclusion of both types of MPs (p < 0.05). Advanced polymer chromatography confirmed that the degradation of PLGA MPs coincided with an increase in composite porosity, mean pore size, and mode pore size. Finally, it was observed that the inclusion of GMPs slowed the degradation of PLGA MPs in vitro and reduced the solution acidity due to PLGA degradation products. Our results suggest that the dual inclusion of GMPs and PLGA MPs is a valuable approach for the generation of early macropores, while also mitigating the effect of acidic degradation products from PLGA MPs on their degradation kinetics. Statement of significance A multitude of strategies and techniques have been investigated for the introduction of macropores with calcium phosphate cements (CPC). However, many of these strategies take several weeks to months to generate a maximal porosity or the degradation products of the porogen can trigger a localized inflammatory response in vivo. As such, it was hypothesized that the fast dissolution of glucose microparticles (GMPs) in a CPC composite also incorporating poly(lactic-co-glycolic acid) (PLGA) microparticles (MPs) will create an initial macroporosity and increase the surface area within the CPC, thus enhancing the diffusion of PLGA degradation products and preventing a significant decrease in pH. Furthermore, as PLGA degradation occurs over several weeks to months, additional macroporosity will be generated at later time points within CPCs. The results offer a new method for generating macroporosity in a multimodal fashion that also mitigates the effects of acidic degradation products. [ABSTRACT FROM AUTHOR]

The present study delineates a relatively simpler approach for fabrication of a macroporous three-dimensional scaffold for bone tissue engineering. The novelty of the work is to obtain a scaffold with macroporosity (interconnected networks) through a combined approach of high stirring induced foaming of the gelatin/carboxymethyl chitosan (CMC)/nano-hydroxyapatite (nHAp) matrix followed by freeze drying. The fabricated macroporous (SGC) scaffold had a greater pore size, higher porosity, higher water retention capacity, slow and sustained enzymatic degradation rate along with higher compressive strength compared to that of non-macroporous (NGC, prepared by conventional freeze drying methodology) scaffold. The biological studies revealed the increased percentage of viability, proliferation, and differentiation as well as higher mineralization of differentiated human Wharton’s jelly MSC microtissue (wjhMSC-MT) on SGC as compared to NGC scaffold. RT-PCR also showed enhanced expression level of collagen type I, osteocalcin and Runx2 when seeded on SGC. μCT and histological analysis further revealed a penetration of cellular spheroid to a greater depth in SGC scaffold than NGC scaffold. Furthermore, the effect of cryopreservation on microtissue survival on the three-dimensional construct revealed significant higher viability upon revival in macroporous SGC scaffolds. These results together suggest that high stirring based macroporous scaffolds could have a potential application in bone tissue engineering. [ABSTRACT FROM AUTHOR]

[Display omitted] • Macroporous Ni–Ce x ZrO (1-x) –Al 2 O 3 catalysts were prepared by washing and hydrothermal methods. • A synergistic effect of macroporosity and crystallinity on MSI was intensively investigated. • The synergistic effect resulted in highly dispersed Ni and abundant oxygen vacancies. • Macroporous structure efficiently inhibited coke formation in dry reforming of methane. • The synergistic effect extended to easy gasification of coke precursor on Ni surface. Dry reforming of methane (DRM) is an outstanding process for transforming methane and carbon dioxide into synthesis gases (H 2 and CO). In this study, a special geometrical modification on Ni/Ce x Zr 1-x O 2 –Al 2 O 3 catalyst was applied by introducing a macroporous structure into the support to accelerate the metal support interaction that optimized the distribution of the active sites over the catalyst. Furthermore, we investigated a synergistic effect of the macroporosity and Ce x Zr 1-x O 2 (CZ) crystallinity over the Ni/Ce x Zr 1-x O 2 –Al 2 O 3 catalyst on its catalytic performance in DRM. Macroporous Ni/Ce x Zr 1-x O 2 –Al 2 O 3 catalysts were prepared via washing (Ni-M a CZA-W) and hydrothermal (Ni-M a CZA-H) methods. Non-macroporous Ni-CZA-H with crystalline CZ was prepared for comparison. The crystalline CZ over macroporous Ni-M a CZA-H had a strong interaction with Ni due to easy accessibility of Ni species to CZ in the macroporous support, resulting in highly dispersed Ni nanoparticles and abundant oxygen vacancies. The unique properties of Ni-M a CZA-H increased catalytic activity and stability in DRM, suppressing coke formation via efficient coke gasification. The Ni species and amorphous CZ over Ni-M a CZA-W resulted in a bimodal Ni size distribution and fast catalyst deactivation. However, even though the crystalline CZ over Ni-CZA-H generated a unimodal distribution of Ni nanoparticles, the non-macroporous Ni-CZA-H resulted in gradual deactivation in the catalytic activity and the production of a different type of coke. [ABSTRACT FROM AUTHOR]

A hydro-mechanical model of a heterogeneous granular bentonite mixture is presented based on discretization into a finite number of "bentonite units", systems in which "megapores" are considered between bentonite grains, which, in turn, contain micro- and macropores. A macroscopic approach is used, where pore levels are associated with superposed homogeneous continua. Mixture heterogeneity is incorporated into the model considering the potentially very different percentage of megapores and grains in adjacent bentonite unit pairs. Mechanical contact is therefore affected, so a strategy is proposed based on porosity values, controlling deformability by the most deformable of the two units in contact. The constitutive formulation was implemented on a numerical solver to simulate a confined hydration test on a granular bentonite mixture with a notable initial local heterogeneity. The reproduced experimental evolution of the swelling pressure, relative humidity distribution, and water inflow was satisfactory. Porosity variation data were synthesized through histograms, describing not only the variation of the maximum and minimum porosity values but also the evolution of the porosity distribution in the mixture. This provides a quantitative description of the homogenization process, allowing an assessment of its scope and technological interest. [ABSTRACT FROM AUTHOR]

Tailored mesoporous activated carbon has been prepared from a new lignocellulosic precursor, cocoa bean husk. The study has focussed on analysing the role the mineral matter of a lignocellusic precursor plays in the development of mesoporosity in activated carbon. Three new approaches have been developed to obtain tailored mesoporosity: i) controlled demineralisation; ii) activation of mixtures of the raw and demineralised cocoa precursor; iii) incorporation of iron via ionic interchange. The results prove that each of the above methods are suitable for developing activated carbon with different pore size distributions, including highly microporous, highly micro and mesoporous and highly macroporous activated carbons. In addition, the activation mechanism of these different carbonised samples has been analysed in order to explain the differences found in the development of porosity. [ABSTRACT FROM AUTHOR]

The porosity of polysiloxane microspheres obtained by emulsion processing of variably modified polyhydromethylsiloxane (PHMS) and subjected to pyrolysis in an Ar atmosphere at 450–650 °C was studied. Materials having micro- and mesopores with specific surface areas (SSAs) of up to 786 m 2 /g and pore volumes of up to 0.35 cm 3 /g were obtained. A high porosity was displayed by the microspheres heated at 600 °C that underwent deep depolymerization processes. Some polysiloxane microspheres were ceramized at temperatures of 1200–1500 °C and were subjected to etching by 35% aqueous HF. The microspheres heated to 1200–1400 °C were free of microcracks, whereas those ceramized at 1500 °C showed microcracks and macropores, although they preserved their spherical structure well. All of the microspheres ceramized at temperatures of 1200–1400 °C had low porosity. HF etching granted high micro- and mesoporosity to the materials ceramized at 1300–1500 °C. Microspheres heated at 1500 °C showed specific surface areas above 1000 m 2 /g after etching. These microspheres had low oxygen contents and were mostly composed of silicon carbide. Since they also showed macroporosity, HF etching of the polysiloxane microspheres ceramized at 1500 °C could be used to obtain hierarchically mesoporous-macroporous ceramic microspheres. [ABSTRACT FROM AUTHOR]

In-house-fabricated aluminum monoliths were washcoated with Co-Re/Al 2 O 3 catalysts for Fischer-Tropsch synthesis using two alumina supports with different texture. On one hand, a commercial mesoporous alumina support was used as reference material. On the other hand, a meso-macroporous alumina was prepared in the laboratory. The macropores were expected to act as transport pores and facilitate diffusion through the catalytic phase volume. Despite showing different porosities, both catalysts presented similar cobalt dispersions and maintained the textural properties observed in the slurried samples once they were deposited onto the metallic monoliths. Being made of a high-thermal-conductivity substrate, the structured catalysts behaved like isothermal reactors with no significant radial thermal gradient being observed inside them during the reactions. Under isothermal conditions, the catalytic differences in Fischer-Tropsch synthesis tests carried out at the same conversion values were ascribed to only diffusional effects imparted by the influence of the macropores. Methane selectivity increased and C 5+ selectivity decreased linearly with catalyst loading. Moreover, for the highest catalyst loading used, methane selectivity was higher and C 5+ selectivity was lower for the catalyst with transport pores. However, when the results of catalysis studies were analyzed as a function of the average catalyst layer thickness; thus under equivalent diffusion lengths, the catalyst containing transport pores showed lower methane selectivity and higher C 5+ selectivity than the reference catalyst over the entire range of layer thicknesses studied. Therefore, the effect of macropores was observed to reduce the diffusion limitations, although at high catalyst loadings the layer thickness determined the selectivity results more than the macroporosity of the layer. [ABSTRACT FROM AUTHOR]

The key step in the construction of efficient and selective analytical separations or sensors is the design of the recognition interface. Biomimicry of the recognition features typically found in biological molecules, using amino acids, peptides and nucleic acids, provides plausible opportunities to integrate biological molecules or their active sites into a synthetic polymeric backbone. Given the basic role of functional amino acids in biorecognition, we focused on the synthesis of polymerizable amino acid derivatives and their incorporation into a polymer-based biohybrid interface to construct generic bioinspired analytical tools. We also utilized polyvinyl alcohol (PVA) as a sacrificial polymer to adjust the porosity of these biohybrid interfaces. The surface morphologies of the interfaces on gold electrodes were characterized by using scanning electron (SEM) and atomic force (AFM) microscopies. The electrochemical behavior of the polymeric films was systematically investigated using differential pulse voltammetry (DPV) to demonstrate the high affinity of the biohybrid interfaces for Cu(II) ions. The presence of macropores also significantly improved the recognition performance of the interfaces while enhancing interactions between the target [Cu(II) ions] and the functional groups. As a final step, we showed the applicability of the proposed analytical platform to create a Cu(II) ion-mediated supramolecular self-assembly on a quartz crystal microbalance (QCM) electrode surface in real time. [ABSTRACT FROM AUTHOR]

Petrophysical analysis using X-ray microtomography provides key textural and compositional information, useful to investigate porous media characteristics of hydrocarbon and geothermal reservoirs. Several approaches, used for rock porosity estimation from tomography data, rely mainly on visual or mathematical segmentation algorithms that attempt to obtain thresholding values to segment a phase solved by pixel analysis resolution. Therefore, porosity is evaluated using only pores above pixel resolution (macroporosity), and dismiss pores sized less than the pixel resolution (microporosity) that can be essential to characterize permeability conditions of geothermal reservoirs. Here we propose an improved method to calculate the total effective porosity and simulate the absolute permeability of rock samples. This method combines the analysis of X-ray computed microtomography (μCT) with the interpretation of data using a powerful thresholding method that is based on the greyscale interclass variance. The 3D volume is segmented into three domains: solid, pores above resolution and, an intermediate region where each pore below resolution is linearly combined with solid matrix resulting in a grey scaled pixel equal to this combination. For the intermediate region, the microporosity was calculated employing a Matlab code that provides a new thresholding value containing pores, both above and below resolution (total porosity). Finally, by using this new calculated thresholding value the total effective porosity was obtained and an absolute permeability simulation was implemented only to the connected pores. Our results show that micropores contribute for nearly 50 percent of the total porosity and that microporosity plays a key role in estimating effective porosity, and assessing the geothermal potential of a rock reservoir. [ABSTRACT FROM AUTHOR]

Earthworms help maintain and enhance the physical condition and function of soils. Their contribution to soil services, such as the flow of water, nutrients and gases, is influenced by earthworm abundance and diversity. In this study mesocosms with either low (dominated by epigeic Lumbricus rubellus ) or high earthworm abundance and diversity ( L. rubellus , Aporrectodea caliginosa and Aporrectodea longa ) were established to explore the relationship with plant production, soil porosity and soil moisture over 444 days. Mesocosms with an abundant and diverse earthworm community had 5% more micro-pores and 70% more macropores. Volumetric soil moisture contents were consistently lower in the mesocosms with an abundant and diverse earthworm community and above-ground accumulation of plant biomass was 35–70% higher over the last 5 months of the study. There was a strong positive relationship between earthworm abundance and diversity, drainage and plant growth and negative relationship with soil moisture. The influence of earthworms on pasture growth was greatest during winter and spring, while their effect on drainage volume was more pronounced during the drier period. This work provides baseline information demonstrating how to relate earthworm abundance and diversity to soil services, and highlights the need to consider their changing influence throughout the season. [ABSTRACT FROM AUTHOR]

Herein, we demonstrate a facile way of fabricating visible-light-active lanthanum and nitrogen – co-doped SrTiO 3 – TiO 2 heterostructured macroporous monolithic materials with bicontinuous morphology by impregnating strontium and lanthanum ions into a preformed porous TiO 2 gel in aqeuous solution containing urea followed by heat treatment in NH 3 atmosphere. The SrTiO 3 macroporous monolithic materials were formed by a solid-state reaction between the TiO 2 gel phase and precipitated SrCO 3 , while Sr 2+ was partially substituted with La 3+ ions. The SrCO 3 was precipitated within the TiO 2 wet gel by the reaction between impregnated Sr 2+ and CO 2 , which was produced by hydrolysis and decarbonation of a chelating agent in the TiO 2 wet gels and by hydrolysis of urea at 60 °C. X-ray powder diffraction studies showed that the incorporation of strontium, lanthanum, and nitrogen could effectively retard the phase transformation of TiO 2 from anatase to rutile and growth of crystallites. XPS analysis confirmed that lanthanum atoms were incorporated into the SrTiO 3 lattice by substituting strontium atoms, and nitrogen was incorporated in the TiO 2 lattice (i) substitutionally forming Ti – N-bonds and (ii) interstitially. The resultant lanthanum and nitrogen – co-doped SrTiO 3 - TiO 2 heterostructured monolithic materials retained a narrow macropore size distribution at the diameter ∼1.7 μ m. [ABSTRACT FROM AUTHOR]

Tillage influences first soil structure and then soil organisms such as earthworms, which are highly involved in the creation of soil macroporosity. This study assessed the temporal dynamics of earthworm-related macroporosity in two ploughed and one unploughed cropping systems. Three sampling dates were chosen: one month before ploughing, and one and five months after the event. Earthworm communities, able to rebuild the macroporosity, were sampled one and five months after ploughing. Before ploughing, the burrow continuity, i.e., the number of burrows with a vertical length greater than 5 cm, was not significantly different in the three systems. It was stable between the three sampling dates in the unploughed system but it decreased by 65% and 46% after ploughing (i.e., in two months) in the organic and the conventional systems, respectively. Five months after ploughing, the burrow continuity remained between two and four times lower than in the unploughed living mulch cropping system. Earthworm biomass was higher and burrow system characteristics (i.e. burrow volume and continuity) were more stable over time in the non-tilled with a living mulch cropping system than in the tilled systems. Earthworm-produced macroporosity was thus substantially decreased after ploughing in conventional and organic systems and had still not totally recovered 5 months later. This can lead to large functional consequences on soil structure and thus on air and water fluxes in the soil. [ABSTRACT FROM AUTHOR]

Revegetation with different plant species has been a strategy to restore the minesoil profile quality in many countries. However, restoration studies about soils degraded by surface coal mining show that it is not easy a simple task to bring back degraded/mined soil to its near original configuration. Thus, our study monitored the physical restoration of a minesoil by 10.6 years over the same experimental unit used by Pauletto et al. (2016), when the minesoil was with 4.8 years of revegetation. The study was conducted in a coal mining area in Candiota city, Southern Brazil. The minesoil was constructed in early 2003, and the experiment was set up between September/October 2007. The species analyzed were Urochloa humidicola , Panicum maximum , and Urochloa brizantha. Natural soil under native vegetation was used as a reference. In April 2018, soil samples were collected in the 0.00–0.10 and 0.10–0.20 m layers, and the following soil attributes were determined: distribution of the water-stable aggregates in different size classes, tensile strength, soil organic carbon content, bulk density, total porosity, macroporosity, and microporosity. In addition, soil penetration resistance was measured in all experimental areas. The minesoil attributes improvement between 4.8 and 10.6 years occurred in depth, mainly with the cohesive aggregates breakdown, and macroporosity and soil organic carbon content increases. At 10.6 years of revegetation, all perennial grasses improved physical conditions up to 0.10 m depth of the minesoil, with good results than those observed in the natural soil. However, compaction persisted in the 0.10–0.20 m layer, as shown mainly by the higher tensile strength of the aggregates, soil penetration resistance, and bulk density. [Display omitted] • Minesoil compaction is a persistent problem even 10.6 years of revegetation. • Minesoil aggregates formed by compression due to traffic of heavy-machinery. • Tensile strength and penetration resistance evidence minesoil compaction. • Roots grasses promotes the breakdown of larger and cohesive aggregates. [ABSTRACT FROM AUTHOR]

• Soil compaction increases bulk density and reduces saturated hydraulic conductivity. • A soil rheology and animal movement models estimate changes in these properties. • The model predicts changes in macroporosity and saturated hydraulic conductivity. • Compaction-induced changes in these soil properties depend on the soil water content. • Predicted temporal changes in soil properties are validated with literature data. Increased soil compaction resulting from livestock treading and use of heavy machinery is a major environmental hazard often linked to degradation of the soil ecosystem and economic services. However, there is a weak quantitative understanding of the spatial and temporal extent of soil compaction and how it modifies soil properties and associated functions. To address this challenge, we developed a framework for systematic modelling soil compaction caused by grazing animals. We considered random movement of livestock in a confined field to describe the spatial variation in the soil that is discretized in square cells with given properties. We then used a rheology model based on Bingham's law to infer compaction-induced changes in soil bulk density and porosity. An associated reduction of saturated hydraulic conductivity is obtained from soil porosity predictions by empirically accounting for macroporosity reduction using a dual-porosity permeability model. This model is coupled with an empirical model of soil structure recovery to account for biological activity (i.e., earthworms and roots). The modelling framework effectively captures primary effects of soil compaction on key soil properties despite lack of explicit consideration of complex effects of compaction such as redistribution of pore sizes and changes in pore connectivity. We tested the model using bulk density, macroporosity and saturated hydraulic conductivity data from a grazing study at the Tussock Creek experimental platform in New Zealand. Data were successfully reproduced by the model. Compaction and recovery trends can be interpreted in terms of model properties associated with management, soil texture and environmental conditions. If data are available for calibration of such properties, the model could be used in agro-ecosystem modelling applications to assess the environmental impacts (such as surface runoff and green-house gas emissions) of livestock-grazing systems and inform management strategies for ameliorating these. [ABSTRACT FROM AUTHOR]

The present study provides evidence of the effectiveness of some termite species in restoring barren soil and in maintaining long-term soil productivity, thereby facilitating sustainable agriculture in sub-Saharan West Africa. Fungus-growers, in particular, move large quantities of soil to cover their food sources with ‘soil sheetings’, which protect the termites during foraging. We selected study sites in northern Burkina Faso from four age-stages of the traditional restoration system Zaï, thus spanning three decades of soil restoration—barren, crusted land, a millet field, and two reforested sites. In a randomized block design, termites were attracted to different organic materials. The aim was to assess the impact of their foraging structures (soil sheetings, foraging holes) on the restoration progress. We quantified soil turnover by termites, macroporosity, water infiltration rate, and physicochemical soil properties. Fungus-growing Odontotermes and Macrotermes species were the decisive soil engineers throughout the year, but only Odontotermes initiated the restoration process. The dry weight of soil bioturbated during the dry season ranged between 216 and 32 tons ha −1 mon −1 in the most rehabilitated Zaï forest and the barren area, respectively. By creating tunnels, the foraging activity of termites increased the water infiltration rate by a factor of 2 to 4. Sheetings built on compost and hay showed significant increase in most parameters relevant for plant growth, especially during the dry season. However, the benefits resulting from the termites’ tunnelling activities (improved water availability and soil aeration via macropores, soil turnover) are in the early stages of Zaï restoration likely to be more essential than the increased nutrient contents in sheeting soil, since water deficit leads to sapling mortality much faster than nutrient shortage. Our study revealed that the impact of termites is dependent on the particular species and their ecological requirements. Further studies in other areas are urgently required to clarify how generally valid our results are. [ABSTRACT FROM AUTHOR]

Calcium phosphate cements (CPCs) have been extensively used in reconstructive dentistry and orthopedics, but it is only recently that CPCs have been combined with stem cells to engineer biological substitutes with enhanced healing potential. In the present study, macroporous CPC scaffolds with defined composition were fabricated using an easily reproduced synthesis method, with minimal fabrication and processing steps. Scaffold pore size and porosity, essential for cell infiltration and tissue ingrowth, were tuned by varying the content and size of polyethylene glycol (PEG) particles, resulting in 9 groups with different architectural features. The scaffolds were characterized for chemical composition, porosity and mechanical properties, then tested in vitro with human mesenchymal progenitors derived from induced pluripotent stem cells (iPSC-MPs). Biomimetic decellularized bone scaffolds were used as reference material in this study. Our manufacturing process resulted in the formation of macroporous monetite scaffolds with no residual traces of PEG. The size and content of PEG particles was found to affect scaffold porosity, and thus mechanical properties. Irrespective of pore size and porosity, the CPC scaffolds fabricated in this study supported adhesion and viability of human iPSC-MPs similarly to decellularized bone scaffolds. However, the architectural features of the scaffolds were found to affect the expression of bone specific genes, suggesting that specific scaffold groups could be more suitable to direct human iPSC-MPs in vitro toward an osteoblastic phenotype. Our simplistic fabrication method allows rapid, inexpensive and reproducible construction of macroporous CPC scaffolds with tunable architecture for potential use in dental and orthopedic applications. [ABSTRACT FROM AUTHOR]

The purpose of this paper is to test uniformity of some soil physical properties in loamy-textured and course-textured soils within intensive orchards and to find out the specific pattern, in order to use it in general orchard management. Undisturbed soil samples were taken from both in-row (IR) and inter-row (ITR) positions within a transect section between two adjacent tree rows. Within this transect there were nine vertical sampling sections spaced 0.5 m apart. Soil bulk density, macro-porosity, saturated hydraulic conductivity and penetration resistance were determined. The pattern of soil physical properties in loamy-sandy and sandy-loamy textured soils is different in intensive orchards from that of arable soils with homogeneous tillage, showing thus the dynamics of soil state. The soil physical properties studied were found to be less favorable to plants in ITR than in IR due to the technological traffic in such environments, after only six years since the orchards were established. The former deep plowing and deep loosening seem to still have favorable consequences for the 0.5 m topsoil physical state in orchards. This shows the beneficial effects of these works that should be recommended whenever such plantations are established on such compacted soils. Cutting tree roots can also be done at a distance of 0.5–0.7 m away from tree rows if an increased control on the irrigation regime and wetted soil volume is required for drip irrigation. [ABSTRACT FROM AUTHOR]

Understanding variability of porous media is important for initiating land management strategies. Objectives were to determine variability of computed tomography (CT)-measured pore characteristics and physical properties of porous media and combine these into principal components (PCs). Core samples were collected from three sites: silvopasture with vegetative buffers (SPBF), watersheds with vegetative buffers (PW), and crop management and prairie management (MP). Soil bulk density ( BD ), saturated hydraulic conductivity ( K s ) and CT-measured pore characteristics were analyzed under buffers and management practices at SPBF; buffer and crop management practices at PW; and native prairie, restored prairie, conservation program, and crop rotation at the MP location. Measured data sets were combined by location for correlation analysis, descriptive statistics, variability analysis, principal component analysis (PCA), and discriminant analysis. Coefficients of variation (CV) showed numbers of pores, macroporosity, mesoporosity and K s were most variable (CV > 0.35), whereas circularity, BD and silt content were least variable (CV < 0.15). The PCA grouped ten pore characteristics and physical properties into three PCs: porosity, water transport and texture. Redundancy analysis showed the soil porosity PC and pore numbers as the most dominant properties at all locations. Results indicate that establishment of vegetative buffers improves porosity. [ABSTRACT FROM AUTHOR]

Novel ceramic structures with multi-scalar porosity were developed using a single preceramic poly(vinyl)silazane to generate asymmetric Si-C-N-based membranes through pyrolytic conversion. Macroporous supports in planar-disc configuration were prepared through a sacrificial filler approach, intermediate structures and microporous layers were deposited via dip-coating. Microporosity in the selective layer was generated through a controlled thermal decomposition of the precursor component in nitrogen atmosphere at temperatures up to 600 °C, resulting in micropores with average pore sizes of 0.8 nm, as investigated by nitrogen adsorption and small-angle X-ray scattering (SAXS). The general feasibility of the single-precursor approach towards selective permeation of gaseous species was demonstrated by the investigation of gas permeances of the generated structures using single-gas permeance testing of He, N 2 , Ar, C 2 H 6 , and CO 2 . By variation of the deposition sequence during preparation of the selective layer by dip-coating, asymmetric structures with ideal permselectivities exceeding predicted Knudsen values were obtained. At 500 °C, He/N 2 and He/CO 2 permselectivities of up to 3.1 and 4.1 were found, respectively, at He permeances up to 3 × 10 −8 mol m −2 Pa −1 s −1 . The new single-material system is a first step towards the potential establishment of new, alternative membrane materials systems, circumventing thermal and chemical incompatibilities between constituents, and increasing material performance due to the applicability under extreme operating conditions. [ABSTRACT FROM AUTHOR]

Intrinsic material skills have a deep effect on the mechanical and biological performance of bone substitutes, as well as on its associated biodegradation properties. In this work we have manipulated the preparation of collagenous derived fiber mesh frameworks to display a specific composition, morphology, open macroporosity, surface roughness and permeability characteristics. Next, the effect of the induced physicochemical attributes on the scaffold’s mechanical behavior, bone bonding potential and biodegradability were evaluated. It was found that the scaffold microstructure, their inherent surface roughness, and the compression strength of the gelatin scaffolds can be modulated by the effect of the cross-linking agent and, essentially, by mimicking the nano-scale size of hydroxyapatite in natural bone. A clear effect of bioactive hydroxyapatite nano-rods on the scaffolds skills can be appreciated and it is greater than the effect of the cross-linking agent, offering a huge perspective for the upcoming progress of bone implant technology. [ABSTRACT FROM AUTHOR]

The development of highly efficient, eco-friendly and cost-effective remediation technology to remove mixed contaminants is now in progress. Here, agarose-Fe nanoparticles (NPs) hydrogel were produced via two green steps to remove mixed contaminants, specifically trichloroethylene (TCE) and hexavalent chromium (Cr(VI)). Approx. 84.9% of Cr(VI) and 93.8% of TCE were simultaneously removed over 24 h in their co-existing solution, while 94.1% of Cr(VI) and 97.2% of TCE were separately removed by agarose-Fe NPs hydrogel. Scanning Electron Microscopy (SEM) suggested that the macroporosity of agarose-Fe NPs hydrogel facilitated the mass transfer between agarose-Fe NPs hydrogels and mixed contaminants, and that Fe NPs were uniformly immobilized into the hydrogel. X-ray Photoelectron Spectroscopy (XPS) and Fourier Transform Infrared Spectroscopy (FTIR) provided evidence supporting the co-removal mechanism. XPS result indicated that: (1) chemical reduction played a role in the removal of both Cr(VI) and TCE; and (2) iron oxides and Fe(III)–Cr(III) complexes might be formed after reaction. FTIR result showed that some functional groups were involved in the removal process. Moreover, the presence of iron oxides were confirmed by FTIR. Both SEM and XPS results verified that encapsulation could describe such immobilization of Fe NPs using agarose. Finally, the kinetics study supported the removal mechanism. Such encapsulation of Fe NPs via a green strategy is simple, quick, and cost-effective, making in situ remediation of mixed contaminants more favorable. [ABSTRACT FROM AUTHOR]

Biomaterials in the form of scaffolds hold great promise in the regeneration of diseased tissues. The scaffolds stimulate cellular adhesion, proliferation and differentiation. While the scaffold composition will dictate their biocompatibility, their porosity plays a key role in allowing proper cell penetration, nutrient diffusion as well as bone ingrowth. Porous scaffolds are processed with the help of a wide variety of techniques. Designing scaffolds with the appropriate porosity is a complex issue since this may jeopardize other physico-chemical properties. From a macroscopic point of view, parameters such as the overall architecture, pore morphology, interconnectivity and pore size distribution, have unique roles in allowing bone ingrowth to take place. From a microscopic perspective, the adsorption and retention of proteins in the microporosities of the material will dictate the subsequent cell adhesion. Therefore, the microstructure of the substrate can determine cell proliferation as well as the expression of specific osteogenic genes. This review aims at discussing the effect of micro- and macroporosity on the physico-chemical and biological properties of scaffolds for musculo-skeletal tissue regeneration. [ABSTRACT FROM AUTHOR]

A hierarchical macro–mesoporous Al 2 O 3 -supported NiK catalyst was prepared using macroporous alumina, and this catalyst was used for steam catalytic cracking of vacuum residue. Ni was well dispersed on the hierarchical macro–mesoporous alumina, which had a high surface area and a highly ordered porous structure. The hierarchical porous catalyst exhibited better catalytic performance (higher liquid yield and higher conversion) than the mesoporous alumina supported NiK catalyst. This good catalytic performance was due to the porosity, which improved access of the vacuum residue to the Ni active sites. Furthermore, the hierarchical porous NiK catalyst showed good stability and was regenerable. [ABSTRACT FROM AUTHOR]

Small amounts of free gas in interstitial sediment pores are known to significantly lower compressional (P-) wave velocity (Vp). This effect, combined with moderately elevated Vp from the presence of gas hydrates, is usually thought to be the cause for the often observed strong negative reflection coefficients of bottom simulating reflections (BSRs) at the base of gas hydrate stability (BGHS). At several locations however, weak BSRs have been observed, which are difficult to reconcile with a presence of gas in sediment pores. We here present a rock physics model for weak BSRs on the Hikurangi Margin east of New Zealand. Thin sections of a fine-grained mudstone sample from a submarine outcrop in the vicinity of a weak BSR show macroscopic porosity in the form of fractures and intrafossil macropores. We apply the Kuster-Toksöz theory to predict seismic velocities for a rock with water-saturated interstitial micropores and gas or hydrates in macroscopic pore space simulating fractures or compliant macropores. We match field observations of a weak BSR with a reflection coefficient of −0.016 with two end-member models; (1) rocks with gas hydrate-filled voids with a concentration of <4% of bulk sediment overlying water-filled voids, or (2) fully gas-saturated voids at a concentration of <2% beneath water-filled voids. A natural system is likely to consist of a combination of these end-members and of macroporosity filled with a mixture of water and gas or hydrate. Our results suggest weak BSRs may be caused by gas hydrate systems in fractures and macropores of fine-grained sediments with fully water-saturated interstitial pore space. Gas may be supplied into the macroscopic pore space by diffusion-driven short-range migration of methane generated within the gas hydrate stability field or, our favoured model based on additional geologic considerations, long-range advective migration from deeper sources along fractures. [ABSTRACT FROM AUTHOR]

• Crop intensification enhances soil macropores hydraulic conductivity compared to mono-cropping. • Long-term NT improves soil structure and water transport properties. • Soil water flux and pore continuity are greater within than between crop rows. • Intensive tillage creates non-persistent changes on soil hydro-dynamic properties. Soil hydraulic properties and pore continuity are important parameters of soil quality and may differ among tillage systems, crop rotations, and change over time. However, there are some contrasting results, depending on soil type, climate and cultivation history on the spatial and temporal variations. The objective of this study was to determine spatio-temporal dynamics of soil hydraulic properties and pore characteristics (i.e., pore volume, effective porosity, and continuity) on a silt loam long-term tillage field experiment, in Agramunt, NE Spain, during two cropping years. Undisturbed soil samples were used to determine soil water retention, θ(Ψ) , and soil hydraulic conductivity, K(Ψ) , curves in two different tillage systems (intensive tillage, IT vs no-tillage, NT), two crop sequences (short fallow-maize, FM vs legume-maize, LM) and two positions (within the row of crops, W-row vs between the rows of crops, B-row). The results revealed that LM had greater specific hydraulic conductivity, K pc in its macroporosity (>1000 µm) than FM due to greater number of effective pores, N pc and effective porosity, ε pc. Soil water content, θ was greater under IT than under NT at higher soil water matric potential, Ψ (≥-3 cm H 2 O), whilst the opposite was observed at lower Ψ (≤ − 50 cm H 2 O). Long-term NT showed greater hydraulic conductivity, K at higher Ψ (≥ − 10 cm H 2 O) than IT, and no difference at lower Ψ. Although IT had greater pore volume, ϕ pc than NT in the macroporosity and coarse mesoporosity (1000–60 µm) pore size classes, NT had two times greater K pc than IT due to increased N pc , ε pc , and pore continuity, C wpc. K(Ψ) and pore characteristics showed spatial variations (W-row vs B-row). W-row had significantly greater K at higher Ψ (≥ − 3 cm H 2 O) than B-row. Temporal dynamics of soil hydraulic properties and pore characteristics were not evident under IT during crop succession. This study shows that LM increases specific hydraulic conductivity of soil macroporosity by increasing the number of effective macropores and the effective porosity. In a Mediterranean climate, this may improve the hydrological functions of agricultural soil and associated crop yield. Further, long-term NT formed a stable number of effective macropores and coarse mesopores, and showed a greater pore continuity in coarse and fine mesopores, resulting in improved soil water flux. [ABSTRACT FROM AUTHOR]

• Eliminated the need for surfactants and urea to produce flexible silica foams. • Systematic exploration of solvent effects on structure formation. • Correlate microstructure to macroscopic properties. Elastic, hydrophobic polymethylsilsesquioxane foams were prepared through a surfactant-free route. Three silane precursors, tetraethyl orthosilicate, methyltriethoxysilane and dimethyldiethoxysilane were used in a two-step, sol-gel process in a solution with variable water:ethanol ratios (from 0.36 to 0.71) to control the phase separation and particle and pore size. The foams were dried at 65 °C under ambient pressure. All samples display a spherical particle network structure, but with reduced particle size (from 4.5 to 3.5 µm) and thinner inter-particle necks for higher water contents. The morphological changes resulted in a higher surface area for higher water contents (S BET between 0.655 m2/g and 0.904 m2/g). The inter-particle neck thickness affected the mechanical properties, with less strain recovery when the water content was high (permanent densification ∼50%). The foams prepared here display a similar performance to those from the literature, but without the need for surfactants or urea in large quantities. [ABSTRACT FROM AUTHOR]

Mining activities take a direct impact on the environment, particularly when this activity is focused on metal-ore exploitation. Abandoned metal mine areas contain different types of residues from ore-processing operations that are typically characterized by high concentrations of heavy metals. One consequence is the generation of acid-mine drainage, caused by the oxidation and hydrolysis of metal sulphides. Mine tail soils have been studied under several points of view, but not on how crack formation affects their properties and functioning, before irreversible hardening. The Cartagena–La Union mining district is one of the more ancient Spanish mining regions. This region is placed at the south-eastern part of Spain, and contains one of the largest lead and zinc ore deposits in South Europe, which was exploited for Au, Ag, Pb, Zn, Fe and Cu from the Phoenician and Carthaginian times. The aim of this research work was to characterize the pedogenesis that occurred in mine tailings of different age and properties, to highlight the physical and hydrological changes that occurred as a consequence of pedogenesis, and their consequences on the environmental pollution risk. Soil profile morphology was studied in the field likewise the surficial pattern of cracks, shear strength, bulk density, and erosion. Laboratory analyses were conducted to characterize physical, chemical, elemental, mineralogical, and hydrological differences between the soil mass in the macro aggregates and in the fissures. Macroporosity was studied through image analysis of thin sections of undisturbed soil samples. X-ray diffraction (XRD) was performed on the clay fraction. Studied soils resulted strongly polluted, especially as for Zn, Pb, Cd, Cl, Mn, and Ni and were classified as different kinds of Spolic Technosol. Crack formation significantly affected shear strength, bulk density, macroporosity, saturated hydraulic conductivity, and element distribution. Gully and tunnel erosion was also driven by crack formation. The mineralogy of the clay fraction revealed that smectites are present, favouring crack opening. Crack formation deeply affected soil features and behaviour, namely hydrological properties and flow of pollutants, which in turn condition environmental health and possible soil stabilization and reclamation strategies. [ABSTRACT FROM AUTHOR]

We show experimentally for the first time that the introduction of macro-pores in the nanoporous catalyst layer of a polymer electrolyte membrane fuel cell can improve its performance. We have achieved a Pt utilization of about 0.23 mg W −1 at 0.6 V which is twice the value of the DOE target for 2020, and three times (0.60 mg W −1 ) smaller than the value of a fully nanoporous reference layer at a catalyst loading of 0.11 mg cm −2 . In this work, monodispersed polystyrene particles with diameters of 0.5 and 1 μm were used as pore formers. Cathode catalyst layers with macroporous volume fractions between 0 and 0.58 were investigated. Maximum performance was observed for fuel cells with a macroporous volume fraction of about 0.52 for a 1 μm thick catalyst layer. The results, which were obtained for the cathode layer, support earlier theoretical predictions that gas access to and water escape from the catalyst can be facilitated by introduction of macropores in the nanoporous layer. [ABSTRACT FROM AUTHOR]

A dual-phase nitrogen-doped TiO 2 –SrTiO 3 macroporous monolithic photocatalyst was fabricated through the impregnation of the preformed TiO 2 gel in a Sr 2+ -containing alcohol–water solution followed by nitridation under a modest flow of ammonia gas at 800 °C for 2 h. The fabricated monolithic photocatalyst was characterized by means of X-ray diffraction (XRD), scanning electron microscopy (SEM), mercury porosimetry, N 2 gas adsorption ( S BET ), X-ray photoelectron spectroscopy (XPS), and ultraviolet–visible (UV–vis) spectroscopy. The XRD results showed that the fabricated monolithic photocatalyst is comprised of two crystalline phases (anatase TiO 2 and SrTiO 3 ) and possesses a highly interconnected (co-continuous) macroporous framework. The photocatalytic activity of the fabricated monolithic photocatalyst was evaluated by the photodegradation of organic dye (Rhodamine B) over the samples under visible light. As expected, the N-doped TiO 2 –SrTiO 3 macroporous monolithic photocatalyst showed a higher photodegradation rate constant (0.0019 min −1 ) compared to the undoped TiO 2 –SrTiO 3 (0.0010 min −1 ) under the identical experimental conditions due mainly to the band gap reduction. [ABSTRACT FROM AUTHOR]

Volumetric muscle loss (VML), characterized by an irreversible loss of skeletal muscle due to trauma or surgery, is accompanied by severe functional impairment and long-term disability. Tissue engineering strategies combining stem cells and biomaterials hold great promise for skeletal muscle regeneration. However, scaffolds, including decellularized extracellular matrix (dECM), hydrogels, and electrospun fibers, used for VML applications generally lack macroporosity. As a result, the scaffolds used typically delay host cell infiltration, transplanted cell proliferation, and new tissue formation. To overcome these limitations, we engineered a macroporous dECM-methacrylate (dECM-MA) hydrogel, which we will refer to as a dECM-MA sponge, and investigated its therapeutic potential in vivo. Our results demonstrate that dECM-MA sponges promoted early cellularization, endothelialization, and establishment of a pro-regenerative immune microenvironment in a mouse VML model. In addition, dECM-MA sponges enhanced the proliferation of transplanted primary muscle stem cells, muscle tissue regeneration, and functional recovery four weeks after implantation. Finally, we investigated the scale-up potential of our scaffolds using a rat VML model and found that dECM-MA sponges significantly improved transplanted cell proliferation and muscle regeneration compared to conventional dECM scaffolds. Together, these results validate macroporous hydrogels as novel scaffolds for VML treatment and skeletal muscle regeneration. [ABSTRACT FROM AUTHOR]

• A novel soil hydrological reservoir cascade scheme model was developed. • Model simulates soil water content (SWC) following various configurations. • Model considers a general matrix flow and two preferential flow regimes. • Simulated SWC values are compared with measured SWC values. • Preferential flows significantly contribute to recharge in karst areas. Models provide quantitative solutions that enable better understanding of karst soils hydrology. A location in central Spain was selected to implement a 1-D hydrological model that uses a reservoir cascade scheme (RCS) approach to simulate soil water content (SWC) at daily resolution. The model simulates SWC for six soil layers and includes additional modules to reproduce preferential flow regime. The soil profile in the model is 0.5 m deep, developed in silt loam soil on top of dolomite marbles. Three different configurations of the model were considered. Configuration 1 considers a basic RCS module, whereas other configurations include preferential flows. Thus, Configuration 2 considers RCS module together with a continuous preferential flow module, where 1 to 5% of available SWC from each layer is drained every day along preferential pathways. Configuration 3 contains a discontinuous preferential flow module in addition to previous modules. The discontinuous preferential flow is only activated during rainfall events occurring after long dry periods. Simulated SWC values are compared with measured SWC values, so model parameters are iteratively adjusted to optimize the model results. The model produces the best simulations implementing the Configuration 3, when matrix flow and two preferential flow regimes are considered. The model shows that preferential flows significantly contribute to recharge and should not be neglected in soil hydrological models and recharge estimations in karst areas. [ABSTRACT FROM AUTHOR]

The thermal conductivity of ordered mesoporous silicas SBA-15 type made up of primary micron size rod-shaped particles, with different states of aggregation and processed as monoliths without any binder has been studied. In particular, the influence of the post-synthesis thermal treatment of materials on the structural and textural characteristics and on the effective thermal conductivity was investigated. Thermal conductivity results were compared with observations by electronic microscopy and to the physicochemical data (X-ray diffraction, nitrogen adsorption/desorption volumetric measurements, 29 Si and 13 C solid-state NMR). It was observed that the elimination of the surfactant on the one hand, and the dehydroxylation of the silica network on the other hand, are partly responsible for variations in thermal conductivity. Thermal conductivity values in the range of 32–46 mW m −1 K −1 was also found dependent on the morphology of particle aggregates that strongly impacts the macroporosity. Good thermal stability of the silica mesostructures was also observed up to 900 °C with low thermal conductivity of about 46 mW m −1 K −1 . These properties make these materials very promising for thermal insulation applications over a large temperature range (room temperature up to 900 °C). [ABSTRACT FROM AUTHOR]

Soil structure influences the soil hydraulic properties, aeration and resistance to root penetration. Many indicators can be used to investigate the changes of soil structure, but using a single indicator or method has limitations. This study evaluates the effects of 15-years tillage management on soil structure with soil bulk density (BD) , penetrometer resistance (PR), soil water retention curve (SWRC), least limiting water range (LLWR) and X-ray computed tomography (CT). The treatments include no-tillage (NT), rotary tillage (RT), and mouldboard plough (MP). Soil bulk density of the 0–30 cm soil profile was measured after the establishment of tillage treatments for 7, 9, 12 and 14-years. The values of PR , SWRC, LLWR, and 3-D pore geometry of the 5–10 and 15–20 cm layers were determined in the 15th year of the experiment. The greater BD in the 0–5 cm layer of NT was not observed after 9 years, but an increased BD in the 5–20 cm layer was found in most years. Tillage had no effect on PR in wet soil. When soil had dried, the NT treatment had a greater PR and it was the lower limiting factor of LLWR, ultimately leading to a narrower LLWR of NT. Both NT and RT showed lower proportions of structural but higher textural pores. The macroporosity (> 50 µm) from X-ray CT was greater than that estimated from SWRC of the 15–20 cm layer. The characteristics of pore morphology were similar under three tillage treatments. Therefore, NT resulted in a narrower LLWR due to the denser soil layer, yet similar macropores may alleviate the negative impacts on crop growth caused by lower LLWR. It was suggested that using LLWR and characteristics of macropores from X-ray CT at the same time is a suitable way to assess soil structure under various tillage practices. • After 15-years no-tillage, the physical quality is poor in 5–20 cm layer reflected by greater BD, PR, and lower LLWR. • Similar properties of macropore weak the usefulness of LLWR for assessing soil structure under no tillage treatment. • Combining LLWR with macropores from X-ray CT is a suitable way to assess soil structure under various tillage practices. [ABSTRACT FROM AUTHOR]

Highlights: [•] RZWQM assessed for atrazine transport in subsurface drainage. [•] RZWQM adequately predicted atrazine concentrations in drainage. [•] Six years of data show atrazine concentrations greater under no-till than till. [•] Atrazine in drainage sensitive to macropore flow and storm timing/intensity. [•] Atrazine in drainage also sensitive to its application rate and tillage. [Copyright &y& Elsevier]

Highlights: [•] The Ecosystem Service rendered by trees on infiltration is site-dependent. [•] Trees’ presence in the pasture improved infiltrability and preferential flow. [•] Trees’ soil–water improvements were masked in the coffee agroforestry system. [•] Generalization of tree's hydrological services need broader empirical data. [Copyright &y& Elsevier]

Abstract: Coke produced from a commercial oven was ground into various particle size ranges as a method to investigate the effect of coke particle size on pore structural parameters. The prepared samples were studied using reflected-light optical microscopy coupled with computerized and manual image analyses. Helium density and surface area measurements were performed on the prepared samples. Results showed that the use of smaller coke particle sizes for sample preparation leads to a loss of larger pores, thus, leading to an inaccurate description of the coke pore structure. This was shown by a decrease in volume porosity and average pore area; and an increase in average cell-wall thickness, coke density, and surface area that accompanied a decrease in the coke particle size. Moreover, a decrease in the ratio between pore area and cell-wall thickness, and a decrease in the ratio between pore long and short axial lengths (Feret's ratio) indicated a loss of large and elongated pores as the coke particle size decreased. However, a comparison of coke particle size ranges of 2.8–4.7mm and 15–16mm indicated that a particle size in a range of 2.8–4.7mm can be employed without compromising pore structural characteristics, yet still enabling representative sampling. [Copyright &y& Elsevier]

Large expanses of riparian vegetation have been destroyed in Brazil, and few studies have focused on biological indicators of soil quality in Brazilian riparian ecosystems. The aim of this study was to assess relationships between the soil fauna and physical, chemical, and biological soil attributes in summer and winter, and to identify the indicators that most effectively distinguish between four study sites in Brazilian Seasonal Semideciduous Forest with different ages: one undisturbed site (NT), and three that have been recovering from disturbance for 5 (R05), 10 (R10), and 20 (R20) years. At each site we overlaid a grid with 30 intersections and selected 15 of them at random for soil sampling (n = 15 points per site). Physical, chemical, and biological (microbiological and soil macrofauna) analyses were performed on these samples. The soil fauna was sampled by two methods (pitfall traps and soil monoliths measuring 25 × 25 × 20 cm) and macrofaunal diversity quantified as richness, cumulated richness, and with Shannon's and Pielou's indices. Patterns in macrofaunal distribution were explored with the parallel discrimination rate and partial redundancy analysis (pRDA) to determine how physical, chemical, and biological attributes affect these patterns. We observed lower Shannon's and Pielou's indices in the winter, for both sampling methods, especially at the most recently recovered site. For monoliths, Hymenoptera were more abundant in the winter and for pitfall traps Mollusca and Chilopoda were only found during summer. Richness, Shannon's and Pielou's indices were only higher at the oldest sites (native and 20 years old) with the monolith data collected in winter. The parallel discrimination rate revealed significant separation between sites, sampling methods, and seasons and indicated Hymenoptera, Diplopoda, Coleoptera, and predators such as Araneae and Opiliones as the principal discriminatory groups. Soil chemistry explained the largest proportion of the pRDA inertia, followed by microbiological and physical attributes. Litter and soil nitrogen content, macroporosity, litter humidity, and microbiological activity and biomass were related most strongly with saprophytic groups and with the oldest sites. These results suggest that organic matter quality and physical soil attributes, in addition to management practices, can accelerate the forest recovery process. [ABSTRACT FROM AUTHOR]