Natively Unfolded FG Repeats Stabilize the Structure of the Nuclear Pore Complex.

Nuclear pore complexes (NPCs) are ∼100 MDa transport channels assembled from multiple copies of ∼30 nucleoporins (Nups). One-third of these Nups contain phenylalanine-glycine (FG)-rich repeats, forming a diffusion barrier, which is selectively permeable for nuclear transport receptors that interact with these repeats. Here, we identify an additional function of FG repeats in the structure and biogenesis of the yeast NPC. We demonstrate that GLFG-containing FG repeats directly bind to multiple scaffold Nups in vitro and act as NPC-targeting determinants in vivo. Furthermore, we show that the GLFG repeats of Nup116 function in a redundant manner with Nup188, a nonessential scaffold Nup, to stabilize critical interactions within the NPC scaffold needed for late steps of NPC assembly. Our results reveal a previously unanticipated structural role for natively unfolded GLFG repeats as Velcro to link NPC subcomplexes and thus add a new layer of connections to current models of the NPC architecture.

In Situ Synthesis of Rare-Earth Hybridized Functional Core-Shell Architectures from Microporous Salt Templates and Capacitance-Adsorption Correlation Mechanisms.

Biochar Porous Carbon (BPC) has become a research hotspot in the fields of energy storage, conversion, catalysis, adsorption, and separation engineering. However, the key problem of pore structure liable to collapse has not yet been addressed effectively. Here, an innovative salt ionic coordination modulation technique is reported to synthesize a new core-shell structure of BPC (Dual-doped porous carbonaceous materials, RHPC3@LaYO3) by the asymmetric load of the f orbital ion, which prevents pore structural collapse. The result shows that the novel asymmetric supercapacitors (ASCs) with an excellent energy density (193.11 Wh·kg-1) and capacitance (267.14 F·g-1) by assembling the prepared porous BPC carrier and RHPC3@LaYO3, which surpass the typical supercapacitor. In order to elucidate the association between adsorption and capacitance, the adsorption coexistence equation (MACE) is constructed with the aim of providing a comprehensive explanation for the mechanism of single-multilayer adsorption. Furthermore, a specific linkage mechanism is discovered using adsorption/ desorption properties to validate the pros/cons of capacitive properties. These results demonstrate the potential of renewable biomass materials as ASCs, which can provide new ideas for the construction of an evaluation approach for the performance of future efficient multi-reaction energy storage devices.

Recent Advances in Preparation and Structure of Polyurethane Porous Materials for Sound Absorbing Application.

Various acoustic materials are developed to resolve noise pollution problem in many industries. Especially, materials with porous structure are broadly used to absorb sound energy in civil construction and transportation area. Polyurethane (PU) porous materials possess excellent damping properties, good toughness, and well-developed pore structures, which have a broad application prospect in sound absorption field. This work aims to summarize the recent progress of fabrication and structure for PU porous materials in sound absorption application. The sound absorption mechanisms of porous materials are introduced. Different kinds of structure for typical PU porous materials in sound absorption application are covered and highlighted, which include PU foam, modified PU porous materials, aerogel, templated PU, and special PU porous materials. Finally, the development direction and existing problems of PU material in sound absorption application are briefly prospected. It can be expected that porous PU with high sound absorption coefficient can be obtained by using some facile methods. The design and accurate regulation of porous structures or construction of multilayer sound absorption structure is favorably recommended to fulfill the high demand of industrial and commercial applications in the future work.

Characterization of anisotropic pore structure and dense selective layer of capillary membranes for long-term ECMO by cross-sectional ion-milling method.

Since the COVID-19 pandemic of 2020-2023, extracorporeal membrane oxygenator (ECMO) has attracted considerable attention worldwide. It is expected that ECMO with long-term durability is put into practical use in order to prepare for next emerging infectious diseases and to facilitate manufacturing for novel medical devices. Polypropylene (PP) and polymethylpentene (PMP) capillary membranes are currently the mainstream for gas exchange membrane for ECMO. ECMO support days for COVID-19-related acute hypoxemic respiratory failure have been reported to be on average for 14 or 24 days. It is necessary to improve opposing functions such that promoting the permeation of oxygen and carbon dioxide and inhibiting the permeation of water vapor or plasma to develop sufficient durability for long-term use. For this purpose, accurately controlling the anisotropy of the pore structure of the entire cross section and functions of capillary membrane is significant. In this study, we focused on the cross-sectional ion-milling (CSIM) method, to precisely clarify the pore structure of the entire cross section of capillary membrane for ECMO, because there is less physical stress on the porous structure applied during the preparation of cross-sectional samples of porous capillary membranes. We attempted to observe the cross sections of commercially available PMP membranes using the CSIM method. As a result, we succeeded in fabricating fine-scale flat cross-sectional samples of PMP capillary membranes. The pore structures and the degree of anisotropy of the cross sections are quantitatively clarified. The achievements and the approaches of this study are being applied to the development of next-generation gas exchange membranes.

Effects of pore characteristics on CO2 adsorption performance of coal slime with different metamorphic degrees.

With the rapid development of Carbon Capture, Utilization and Storage (CCUS) technology, it is necessary to explore the feasibility of coal slime as a porous carbon material for CO2 capture. In this paper, scanning electron microscopy (SEM) was used to observe the morphological characteristics of coal slime samples with different metamorphic degrees, and the pore structure of coal slime was explored by low temperature N2 adsorption and low-pressure CO2 adsorption experiments. The pore distribution characteristics were analyzed, and the adsorption law of different metamorphic degrees were summarized through CO2 isothermal adsorption experiments. The results showed that: The specific surface area (SSA) and pore volume (PV) of the mesopores of the coal slime exhibited a U-shaped distribution with coal rank, and are much smaller than that of its micropores. Micropores less than 2 nm are the main adsorption space of coal slime, its PV accounted for 59%, 60%, 71%, and SSA accounted for 92%, 93%, 95%, obviously, which are dominant at all stages. The linear correlation fitting coefficients R2 between the limiting adsorbed amount a of CO2 and the micropores PV and the SSA were up to 0.830 and 0.887, respectively. The coal slime has good adsorption performance for CO2. Based on the Langmuir model to fit the limit adsorption amount, a-value can reach 41.774 cm3 g-1, 32.072 cm3 g-1, 38.457 cm3 g-1 at 303 K with the increase of Rmax. Studying the impact of coal slime on CO2 adsorption performance provides a theoretical basis for the subsequent preparation of energy storage materials and is of great significance for the safe, efficient and economic capture and sequestration of CO2, to alleviate the serious situation of the environment and realizing the dual-carbon goal.

Response of soil enzymatic activity to pore structure under inversion tillage with organic materials incorporation in a Haplic Chernozem.

Soil pore structure affects microbial survival environmental conditions and thus enzyme activity. The mechanisms underlying returning organic materials on soil pore structure and enzymatic activity, however, remain unclear. We therefore conducted a field experiment in the fall of 2018 in northeastern China with a chernozem soil and four treatments: CT, conventional tillage; SCT, returning maize straw incorporation with conventional tillage; SIT, returning maize straw incorporation with inversion tillage; SMIT, returning maize straw and organic manure with inversion tillage. Soil samples were collected from the 0-15 cm and 15-35 cm layers in the fall of 2021. We used X-ray computed tomography to analyze the characteristics of pore structure and extracellular enzymatic stoichiometry to evaluate the limiting factors for soil microorganisms. Inversion tillage and organic materials incorporation can alter the micromorphological structure of entire soil layer, leading to the rearrangement of soil particles and nutrients, thereby augmenting the physicochemical properties in subsoil layer. SMIT exhibited a substantial increase in the number of macropores, porosity and fractal dimension, compared to SCT and SIT. This led to a significantly increased in soil enzyme activities of carbon and nitrogen-limited in SMIT, with increases ranging from 11.67% to 40.16% and from 8.81% to 21.43%, respectively (P < 0.05). Analysis using structural equation modeling revealed that returning organic material was conducive to the development of soil pore structure, characterized by an increase in macropores and fractal dimension and a decrease in the Euler number, had a positive correlation with soil enzyme activity. This, in turn, led to an alleviation in microbial nitrogen limitation. These results indicate that SMIT could serve as a viable choice in enhancing soil structure and fostering a favorable environment for microbial survival. Moreover, they offer essential insights into the microbial strategies responsible for the breakdown of organic matters in Hapli-Udic Cambisol.

"One-stone, Two-Birds": Zinc-Rich Metal-Organic Frameworks as Precursors for High-Entropy Zn-Air Battery Electrocatalysts with Hierarchical Pore Structures.

The active sites of inexpensive transition metal electrocatalysts are sparse and singular, thus high-entropy alloys composed of non-precious metals have attracted considerable attention due to their multi-component synergistic effects. However, the facile synthesis of high-entropy alloy composites remains a challenge. Herein, we report a "one-stone, two-birds" method utilizing zinc (Zn)-rich metal-organic frameworks as precursors, by virtue of the low boiling point of Zn (907 °C) and its high volatility in alloys, high-entropy alloy carbon nanocomposite with a layered pore structure was ultimately synthesized. The experimental results demonstrate that the volatilization of zinc can prevent metal agglomeration and contribute to the formation of uniformly dispersed high-entropy alloy nanoparticles at slower pyrolysis and cooling rates. Simultaneously, the volatilization of Zn plays a crucial role in creating the hierarchical porous structure. Compared to the zinc-free HEA/NC-1, the HEA/NC-5 derived from the precursor containing 0.8 Zn exhibit massive micropores and mesopores. The resulting nanocomposites represent a synergistic effect between highly dispersed metal catalytic centers and hierarchical adsorption sites, thus achieving excellent electrocatalytic oxygen reduction performance with low catalyst loading compared to commercial Pt/C. This convenient zinc-rich precursor method can be extended to the production of more high-entropy alloys and various application fields.

The soil pore structure encountered by roots affects plant-derived carbon inputs and fate.

Plant roots are the main supplier of carbon (C) to the soil, the largest terrestrial C reservoir. Soil pore structure drives root growth, yet how it affects belowground C inputs remains a critical knowledge gap. By combining X-ray computed tomography with 14 C plant labelling, we identified root-soil contact as a previously unrecognised influence on belowground plant C allocations and on the fate of plant-derived C in the soil. Greater contact with the surrounding soil, when the growing root encounters a pore structure dominated by small (< 40 µm Ø) pores, results in strong rhizodeposition but in areas of high microbial activity. The root system of Rudbeckia hirta revealed high plasticity and thus maintained high root-soil contact. This led to greater C inputs across a wide range of soil pore structures. The root-soil contact Panicum virgatum, a promising bioenergy feedstock crop, was sensitive to the encountered structure. Pore structure built by a polyculture, for example, restored prairie, can be particularly effective in promoting lateral root growth and thus root-soil contact and associated C benefits. The findings suggest that the interaction of pore structure with roots is an important, previously unrecognised, stimulus of soil C gains.

Optimizing pre-carbonization temperature of sesame residue for hierarchical porous carbon materials in high-performance supercapacitor applications.

In this paper, the sesame residue, a common biomass waste, was used as a precursor to synthesize N,O co-doped porous carbon materials via a simple pre-carbonization and KNO3activation two-step strategy. The apparent morphology and supercapacitor performance of the obtained materials can be regulated by changing the pre-carbonization temperature (0 °C, 300 °C and 600 °C). The consequences demonstrate that a large number of C-C and C-O bonds in sesame residue undergo cleavage and form abundant pore structure at the pre-carbonization temperature of 300 °C. After KNO3activation, the material has a moderate specific surface area (1073.4 m2g-1) and affluent heteroatom content (N: 7.52 at%, O: 17.65 at%). As a result, the SS-300 electrode displays exceptional capacitive performance (specific capacitance up to 312.7 F g-1at 0.5 A g-1) and outstanding cyclic stability (capacitance retention reaching 98.3% at 10 A g-1after 8000 charge-discharge cycles). Moreover, the symmetric supercapacitor assembled by SS-300 exhibits high energy densities in both 6 M KOH (4.58 Wh kg-1) and 1 M Na2SO4(15.60 Wh kg-1), highlighting the potential of this material for energy storage applications.

Preparation of high performance porous carbon by microwave synergistic nitrogen/phosphorus doping for efficient removal of Cu2+ via capacitive deionization.

Sargassum biochar has potential advantages as an electrode material due to its natural microscopic pore channels. However, conventional pyrolysis method is prone to thermal damage to the biochar, and incapable to form a complete pore structure resulting in poor biochar electrode performance. In this study, a strategy of microwave pyrolysis coupled with KOH activation was used to prepare nitrogen/phosphorus double-doped graded porous biochar (STC) using ammonium dihydrogen phosphate as dopant. The carbon material STC-1.24-800 prepared by the optimal parameters had a high specific surface area (SSA) of 1367.6 m2 g -1 and a total pore volume of 1.499 cm3 g-1. The precise inside-out heating characteristics of microwave facilitated the generation of suitable meso-micropore distribution ratios in carbon, and the graded porous structure provided abundant active sites for charge accumulation and ion diffusion. The doped nitrogen/phosphorus atoms responding to the microwave field, generated spin to promote microwave absorption, introducing surface structural defects to produce electron density differences. The change in the nature of the electron donor and its electron density enhanced the electrical conductivity and chemical stability of STC. Nitrogen/phosphorus polar surface functional groups improved hydrophilicity and wettability. STC-1.24-800 had a higher specific capacitance of 531 F g-1 and exhibits great cycle performance in capacitive deionization (CDI) applications (1.0 V, 50 mg L-1 Cu2+) as well as adsorption performance (56.16 mg g -1). The present work can provide a novel feasible idea for preparing diatomically doped graded porous biochar for CDI electrode application by microwave irradiation.

Imidazole-octyl mixed-mode stationary phase based on macroporous silica for the purification of ovomucoid and ovotransferrin.

A process-simplified hard template approach was established to synthesize the monodisperse macroporous silica microspheres with homogeneous structures by twice alkali-thermal treatment and calcination routes. Porous vinyl-functionalized polysesquioxane microspheres (V-PMSQ) were synthesized through a hydrolyzation-polycondensation method and used as templates. The template particles with large aperture and high pore volume were obtained by adjusting the pH value and reaction time of the twice alkali-thermal reaction. After calcination, monodisperse silica microspheres with an average pore size of 30 nm, homogeneous pore structures, and narrow particle size distribution were fabricated, which can be directly used as chromatographic matrices without classification. After that, a new reversed-phase/strong anion-exchange (RP/SAX) mixed-mode stationary phase Sil-S-VOIM was prepared by bonding the 1-vinyl-3-octyl-imidazole ligands to the above silica microspheres through a "thiol-ene" click reaction. The performance of the Sil-S-VOIM column was evaluated by one acidic protein (transferrin) and two basic proteins (lysozyme, α-chymotrypsin) and compared to a single imidazole-modified Sil-S-VIM column and an octyl-modified Sil-C8 column, respectively. Due to the synergistic effect of electrostatic repulsion and hydrophobic interactions, baseline separations of the above proteins were observed only on the Sil-S-VOIM column, with resolutions of 2.55 and 2.01 between lysozyme and transferrin, and between transferrin and α-chymotrypsin, respectively, indicating good selectivity and separation ability compared with single-mode stationary phases. It was applied to the isolation of egg white samples with peaks identified by SDS-PAGE and MALDI-TOF-MS. The results showed that the selective retention and isolation of ovomucoid and ovotransferrin were successfully achieved, with yields of 78.8% and 67.2%, respectively. The protocol described in this work is simpler, faster, and has higher protein recovery. Overall, this new mixed-mode stationary phase provided a promising potential for the separation and determination of intact proteins.

Three-Dimensional Fe Single-Atom Catalyst for High-Performance Cathode of Zn-Air Batteries.

Designing cost-effective and highly active oxygen reduction reaction (ORR) catalysts is critical for the development of Zn-air batteries (ZABs). Iron-nitrogen-carbon (Fe-N-C) catalysts with single-atom Fe-Nx active sites are considered as one of the most promising alternatives to noble Pt but are hindered by unsatisfactory activity and durability. Herein, a NaCl template-assisted in situ pyrolysis technique is utilized to massively fabricate Fe-N-C single-atom catalysts (SACs) anchored on the three-dimensional open-pore carbon networks (denoted as 3D SAFe). The 3D SAFe catalyst exhibits ultrahigh activity with a half-wave potential of 0.90 V (vs RHE), benefiting from the enhanced mass diffusion and the increased amount of effective Fe-N4 sites. Consequently, the ZABs assembled with 3D SAFe deliver high peak power density up to 156 mW cm-2 and outstanding durability of 80 h, suggesting the application potential of the 3D SAFe catalyst. This work inspires the rational design and synthesis of highly efficient SACs for ZABs.

Simultaneous enhancement of soil properties along with water-holding and restriction of Pb-Cd mobility in a soil-plant system by the addition of a phosphorus-modified biochar to the soil.

Soil quality deterioration and heavy metal contamination have greatly limited soil productivity in mining areas. As soil is a complex system with various properties and interactions, it is imperative to conduct a comprehensive investigation to understand the amendment's mechanisms at work in the soil in mining areas as well as effective ways to address its deteriorating quality. In this study, a potassium dihydrogen phosphate-modified maize straw-cow dung biochar (PBC) was applied as a soil amendment. Various physicochemical properties of the soil including organic matter, total nitrogen, available phosphorus, and pore characteristics were analyzed. This study also assessed soil-saturated water content and soil moisture characteristic curve. Lettuce biomass was measured and changes in various speciation of Pb and Cd in the soil, and the accumulation of Pb and Cd in lettuce were examined. Results showed that the addition of PBC increased soil organic matter, total nitrogen, and available phosphorus while reducing soil bulk density, it also increased soil porosity, saturated water content, and capillary water capacity. Soil structure analysis using CT scanning revealed that 3% PBC increased the macrospores volume fraction while 5% PBC made the pores more uniform. Lettuce biomass increased by 53.3%. 5% PBC resulted in a 56.79% and 38.30% reduction in Pb and a 44.56% and 16.60% reduction in Cd in roots and shoots of lettuce respectively. PBC facilitated the transformation of Pb and Cd from unstable fractions to stable fractions through complexation and precipitation. Overall, the addition of PBC effectively improved soil nutrients, porosity, and water-holding capacity, promoted plant growth, immobilized Pb and Cd, as well as reduced the bioavailability in contaminated-soil from mining areas. This study provides an effective strategy and a new perspective for the remediation of Pb-Cd-contaminated soils.

Impact of different structures of biochar on decreasing methane emissions from sewage sludge composting.

Methane (CH4) emissions from sewage sludge composting can be reduced by using biochar more effectively. This study investigates the impact of different structure of biochar on CH4 emissions during sewage sludge composting. Corncob biochar (CB, pore size = 35.3990 nm), rice husk biochar (RB, pore size = 3.4242 nm) and wood biochar (WB, pore size = 1.6691 nm) were applied to the composting. The results showed that biochar decreased CH4 emissions, mainly through the indirect effect of improving the pile environment. Compared with the control group (CK), the biochars with smaller pore structures, WB and RB, reduced CH4 emissions by 41.83% and 33.59%, respectively, compared to only 8.20% for CB, which has a larger pore structure. In addition, RB and WB increased the free air space (FAS) by more than 10% and CB improved the microbial diversity. Methanothermobacter was reported in WB and RB, with an abundance of 45.45% in WB. Redundancy analysis (RDA) showed that pore size was positively correlated with the CH4 emission rate. The results of this study can provide a theoretical reference for CH4 reduction from biochar co-composting of sewage sludge.

Particulate matter capturing over manganese dioxides with different crystal structures.

Particulate matter (PM) is the main contributor to air pollution, and filtration has been reported to be promising for PM capturing. Considering the complexity of polluted air (volatile organic compounds (VOCs) and ozone are likely concomitant with PM particles) and in view of the versatility of MnO2 for the degradation of VOCs and ozone, the feasibility of MnO2 materials as PM filtering media was investigated in this study, and the effect of crystal structure on PM filtration was clarified. Compared with the layered δ-MnO2, the MnO2 with tunnel structure (including 1 × 2-, 2 × 2- and 3 × 3-MnO2) exhibited greatly enhanced PM removal efficiencies, and particularly, the 3 × 3-MnO2 possessed not only significant activity for adsorbing PM particles but also high utilization efficiency of the active surface. Physicochemical properties of the adsorbents were studied by XRD, ATR, isothermal N2 adsorption, SEM and (HR)TEM. The correlation between pore characteristics and particle elimination activity demonstrates that the most developed mesoporous structure of the 3 × 3-MnO2 sample played an important role in strengthening the PM adsorption capability. Further comparison of the surface properties of the fresh and spent samples reveals that with respective to the occasion of δ-MnO2, the structure of 3 × 3-MnO2 was robust enough to resist collapse after PM capturing and the great accommodation of the inorganic and organic PM substances in the voluminous pores induced strong affinity between PM particles and 3 × 3-MnO2. Thereby, a higher particle filtration ability was retained.

Optimized Sieving Effect for Ethanol/Water Separation by Ultramicroporous MOFs.

High-purity ethanol is a promising renewable energy resource, however separating ethanol from trace amount of water is extremely challenging. Herein, two ultramicroporous MOFs (UTSA-280 and Co-squarate) were used as adsorbents. A prominent water adsorption and a negligible ethanol adsorption identify perfect sieving effect on both MOFs. Co-squarate exhibits a surprising water adsorption capacity at low pressure that surpassing the reported MOFs. Single crystal X-ray diffraction and theoretical calculations reveal that such prominent performance of Co-squarate derives from the optimized sieving effect through pore structure adjustment. Co-squarate with larger rhombohedral channel is suitable for zigzag water location, resulting in reinforced guest-guest and guest-framework interactions. Ultrapure ethanol (99.9 %) can be obtained directly by ethanol/water mixed vapor breaking through the columns packed with Co-squarate, contributing to a potential for fuel-grade ethanol purification.

Integrated Porous Cu Host Induced High-Stable Bidirectional Li Plating/Stripping Behavior for Practical Li Metal Batteries.

The double-sided electrodes with active materials are widely used for commercial lithium (Li) ion batteries with a higher energy density. Accordingly, developing an anode current collector that can accommodate the stable and homogeneous Li plating/stripping on both sides will be highly desired for practical Li metal batteries (LMBs). Herein, an integrated bidirectional porous Cu (IBP-Cu) film with a through-pore structure is fabricated as Li metal hosts using the powder sintering method. The resultant IBP-Cu current collector with tunable pore volume and size exhibits high mechanical flexibility and stability. The bidirectional and through-pore structure enables the IBP-Cu host to achieve homogeneous Li deposition and effectively suppresses the dendritic Li growth. Impressively, the as-fabricated Li/IBP-Cu anode exhibits a remarkable capacity of up to 7.0 mAh cm-2 for deep plating/stripping, outstanding rate performance, and ultralong cycling ability with high Coulombic efficiency of ≈100% for 1000 cycles. More practicably, a designed pouch cell coupled with one Li/IBP-Cu anode and two LiFePO4 cathodes exhibits a highly elevated energy density (≈187.5%) compared with a pouch cell with one anode and one cathode. Such design of a bidirectional porous Cu current collector with stable Li plating/stripping behaviors suggests its promising practical applications for next-generation Li metal batteries.

A well-defined hierarchically porous metal-organic framework and its application in separation and purification of steviol glycosides.

The separation and removal of stevioside from natural product steviol glycosides to obtain high-purity rebaudioside A is of great significance for the application of steviol glycosides in food, medicine, and other fields. Here, in order to explore the adsorbent pore structure suitable for the separation of stevioside and rebaudioside A, a hierarchically porous amino-functionalized metal-organic framework (HP-NH2 -MIL-53) with an appropriate and narrow pore size distribution was prepared using a modulator-induced defect-formation strategy. The results showed that the hierarchically porous structure with micropores and mesopores increased the specific surface area and exposed amino groups compared with original metal organic framework (NH2 -MIL-53), and the maximum adsorption capacity of HP-NH2 -MIL-53 for stevioside and rebaudioside A was 233.89 mg/g. The narrow pore size distribution close to 3.80 nm promoted the screening effect, resulting in a maximum adsorption selectivity of 4.13. This work proves that when the pore size of the adsorbent is between 1.41 and 3.80 nm, it has a certain pore size screening effect on stevioside and rebaudioside A, and the hierarchically porous metal-organic frameworks provide a pre-design idea of adsorbent structure for the separation of natural products with molecular weight of 800-1000 Da.

The Stabilizing Effect of Carboxymethyl Cellulose on Foamed Concrete.

Foam concrete is widely used for its excellent properties, such as light weight, heat insulation, fire resistance, and sound insulation. The stability of foam is the main factor that affects the mechanical performance of foam concrete. The experiments are designed from two perspectives: the foam's stability performance and the foam concrete's modification effect. The effects on foam volume, foam half-life, foam bleeding rate, and foam pore size were investigated based on different concentrations of foam stabilizer CMC (0%, 0.1%, 0.2%, 0.3%, 0.4%, 0.5%). A combination of macroscopic testing and microscopic analysis, a comparative study of dry density, water absorption test, mechanical property test, and pore structure analysis were conducted after using the modified foam for foam concrete. It is shown that the addition of CMC has an enhanced effect on foam stability. Foaming volume, water secretion rate, and average pore size showed a decreasing trend with the increase of CMC admixture, while the foam half-life displayed an increasing trend. In addition, adding CMC reduces the dry density and improves water absorption and compressive strength. The pore structure development of foam concrete has a noticeable improvement effect, and the optimal amount of admixture is 0.4%. Research results provide a reference for applying thickening foam stabilizer CMC in foam concrete.

Sewage sludge ash-incorporated stabilisation/solidification for recycling and remediation of marine sediments.

Finding suitable disposal sites for dredged marine sediments and incinerated sewage sludge ash (ISSA) is a challenge. Stabilisation/solidification (S/S) has become an increasingly popular remediation technology. This study sheds light on the possible beneficial use of ISSA together with traditional binders to stabilise/solidify marine sediments. The performance of the binders on S/S of sediment 1 (clean) and sediment 2 (contaminated) was also compared. The results showed that the use of ISSA as part of the binder was effective in promoting the strength of the sediment with a high initial moisture content due to ISSA porous and high water absorption characteristics. The sediments treated with 10% cement and 20% ISSA attained the highest strength. Also, cement hydration as well as pozzolanic reactions between ISSA and Ca(OH)2 made contributions to the strength development. This was supported by the microstructural analysis, in particular the porosity results. In terms of environmental impacts, two leaching tests (toxicity characteristic leaching procedure and synthetic precipitation leaching procedure) found that all the S/S treated sediment by 10% lime and 20% ISSA resulted in the lowest leachate concentrations under the on-site reuse scenario or under simulative acidic rainfall conditions. Therefore, recycling waste ISSA with lime can be used as an appealing binder to replace cement to stabilise/solidify dredged marine sediments for producing fill materials.