Hydration Properties Research Articles

Hydrophobic Clusters Regulate Surface Hydration Dynamics of Bacillus subtilis Lipase A.

The surface hydration diffusivity of Bacillus subtilis Lipase A (BSLA) has been characterized by low-field Overhauser dynamic nuclear polarization (ODNP) relaxometry using a series of spin-labeled constructs. Sites for spin-label incorporation were previously designed via an atomistic computational approach that screened for surface exposure, reflective of the surface hydration comparable to other proteins studied by this method, as well as minimal impact on protein function, dynamics, and structure of BSLA by excluding any surface site that participated in greater than 30% occupancy of a hydrogen bonding network within BSLA. Experimental ODNP relaxometry coupling factor results verify the overall surface hydration behavior for these BSLA spin-labeled sites similar to other globular proteins. Here, by plotting the ODNP parameters of relative diffusive water versus the relative bound water, we introduce an effective "phase-space" analysis, which provides a facile visual comparison of the ODNP parameters of various biomolecular systems studied to date. We find notable differences when comparing BSLA to other systems, as well as when comparing different clusters on the surface of BSLA. Specifically, we find a grouping of sites that correspond to the spin-label surface location within the two main hydrophobic core clusters of the branched aliphatic amino acids isoleucine, leucine, and valine cores observed in the BSLA crystal structure. The results imply that hydrophobic clustering may dictate local surface hydration properties, perhaps through modulation of protein conformations and samplings of the unfolded states, providing insights into how the dynamics of the hydration shell is coupled to protein motion and fluctuations.

Molecular Dynamic Simulation Study on Replacement of Methane Hydrates with Carbon Dioxide Under Different Temperatures, Pressures, and Concentrations of Ethylene Glycol.

In order to alleviate the world energy resources crisis, the research and development of natural gas hydrates has a very important economic value and strategic significance. The CH4-CO2 replacement method can not only achieve geological storage of carbon dioxide but also more effectively mine natural gas hydrates. Based on molecular dynamics theory and the properties of natural gas hydrates, this paper delves into the replacement of methane hydrate with carbon dioxide under different temperatures, pressures, and concentrations of ethylene glycol (EG). We established a CO2-Hydrate model and three CO2/EG-Hydrate models with different concentrations of EG, and we simulated the radial distribution function (RDF), mean square displacement (MSD), and relative density distribution of each particle in the system in different conditions. The higher the temperature, the more unstable the methane hydrates are, and the methane hydrates are more prone to decomposition. Compared with 280 and 290 K, the temperature of 270 K is more favorable for carbon dioxide molecules to enter the hydrate layer and form carbon dioxide hydrates. The changes in pressure have little impact on the decomposition of methane hydrates, the rupture of water cages of methane hydrates, and the number of carbon dioxide molecules entering the hydrate layer under temperatures of 280 K and pressures of 1, 4, and 7 MPa. But overall, a pressure of 1 MPa is more conducive for carbon dioxide molecules to enter the hydrate layer and form carbon dioxide hydrates. Adding EG to CO2 molecules can inhibit the decomposition of methane hydrates. However, the higher the concentration of EG, the faster the decomposition of methane hydrates. The degree of fracture of the water cages in methane hydrates is greater under pure CO2 conditions. Adding EG to CO2 molecules is more conducive for CO2 molecules to enter the hydrate layer and form carbon dioxide hydrates. This review is of great significance to improve the mining efficiency and CO2 storage efficiency of the replacement of natural gas hydrates with CO2.

Exploring the application of hydrazine hydrate in protonic ceramic fuel cells: Strategies and performance improvements

Hydrazine hydrate, characterized by its high hydrogen content and eco-friendliness, garners extensive attention in the field of fuels. Its high energy density and rapid decomposition capabilities render it a promising fuel option for Proton-Conductor Solid Oxide Fuel Cells (PCFCs). Given the unique properties of hydrazine hydrate, this study employs a dendritic porous anode structure to facilitate faster fuel transport. Additionally, the influence of operational temperature and concentration of hydrazine hydrate as fuel on cell performance is analyzed. An effective vapor management strategy is implemented to address its decomposition into water vapor, resulting in a significant 23.17 % increase in the maximum power density (MPD) of the cell. To further enhance the performance of hydrazine hydrate fuel in PCFCs, a Pt–Al spherical catalyst is integrated within the anode structure of the cell. This approach notably improves the cell performance, yielding an additional 14.98 % increase in MPD. This design not only augments the electrical output but also effectively mitigates the degradation of the interface between the anode and the electrolyte. These optimization measures significantly improve the lifespan and reliability of the cell. The outcomes of this study demonstrate the practical feasibility of using hydrazine hydrate as a fuel in PCFCs.

Effect of waste clay brick powder on microstructure and properties in blended oil well cement pastes at HTHP conditions

The use of waste materials to improve the thermal stability of oil well cement (OWC) at high temperature and high pressure (HTHP) conditions has received increasing attention. This study investigated the performance of sustainable blended OWC pastes by recycling waste clay brick powder (CBP) as a partial substitute for commercial high temperature resistant additives (silica flour, SF). The main objective was to assess the impact of these substitutions on the hydration, microstructure and mechanical properties of blended OWC. CBP was incorporated at substitution rates of 25 wt%, 50 wt%, 75 wt% and 100 wt% by weight of SF. These pastes were firstly precured at 50 °C for 7 days (to simulate the primary cementing operation prior to steam injection), and then thermally cycling cured at 300 °C/13.0 MPa (to simulate the steam injection process). The study conducted comprehensive tests and analyses, including compressive strength, gas permeability, hydration products and microstructural analyses. The results showed that the suitable substitution rate of CBP in this study was 25 wt%-50 wt%. At these substitution levels, the blended OWC pastes had good compressive strength (18.5 MPa and 17.9 MPa) and low gas permeability (3.1 × 10−3 mD and 4.51 × 10−3 mD). From the environmental and economic analyses, the energy intensity and CO2 emissions of all blended OWCs were significantly lower compared to those of conventional OWC. Meanwhile, the cost of blended OWC in this study was significantly lower compared to that of the commercial SF-OWC system. Overall, this study highlighted the potential of recycling waste materials to promote raw material sustainability and improve the performance of OWC pastes at HTHP conditions.

Clinkering and hydration of alite-belite-ye'elimite cement with increasing ye'elimite percentage

Alite-belite-ye'elimite (ABY) cement is considered to be eco-cements with adequate mechanical properties and fewer CO2 emissions. The phase assemblage and ye’elimite content of ABY cement play a very important role in cement properties. In this study, ABY clinkers with increasing ye'elimite percentage (0.3 wt%-36.4 wt%) were prepared at 1300 °C and the phase composition was characterized by Rietveld Quantitative Phase Analysis combined with energy dispersive X-ray spectrometry. The ye'elimite formed with a calculated composition of Ca3.92Mg0.02Al2.81Fe0.05Si0.04S1.16, incorporating additional sulfur compared to the theoretical value. In addition, the hydration properties of heat evolution, hydration products and compressive strength of ABY cement are studied. The result shows that the increase of ye'elimite content leads to a more intense initial heat release and a higher cumulative heat release. The presence of ye'elimite inhibits the hydration of alite at early ages. ABY mortars with increasing ye'elimite (15.8 wt%) exhibited a higher strength (29.6 MPa) at 3 days by the contribution of ye'elimite hydration, and an increase (47.4 MPa) at 28 days. An adequate proportion of ye'elimite (<15 wt%) is favorable to the performance of ABY cement, and releases 12% less CO2.

Composition and Functional Properties of the Edible Spear and By-Products from Asparagus officinalis L. and Their Potential Prebiotic Effect.

Asparagus is a healthy food appreciated for its organoleptic characteristics, nutritional composition and physiological properties. During its industrial processing, a large amount of by-products are generated, since only the apical part of the vegetable is considered edible and a large amount of by-products are generated that could be of nutritional interest. Therefore, the nutritional composition of the edible part and the two by-products of the plant (root and stem) was evaluated, including dietary fiber, inulin, low-molecular-weight carbohydrates, low-molecular-weight polyphenols and macromolecular polyphenols. The hydration properties, oil retention capacity, glucose retardation index and impact on bacterial growth of both probiotic bacteria and pathogenic strains were determined. All samples were high in fiber (>22 g/100 g dw), fructans (>1.5 g/100 g dw) and polyphenolic compounds (>3 g/100 g dw) and had good water-, oil- and glucose-binding capacity. In addition, they promoted the growth of probiotic strains but not pathogenic ones. The effects were more pronounced in the spear by-product samples and appear to be related to the components of dietary fiber. The results indicate that edible spear has potential beneficial effects on host health and microbiota when ingested as part of a healthy diet, while the by-products could be used as supplements and/or as natural ingredients in fiber-enriched foods that require emulsification and are intended to achieve a prebiotic effect.

Modification of pea dietary fibre by superfine grinding assisted enzymatic modification: Structural, physicochemical, and functional properties

Using the optimal extraction conditions determined by response surface optimisation, the yield of soluble dietary fibre (SDF) modified by superfine grinding combined with enzymatic modification (SE-SDF) was significantly increased from 4.45 % ± 0.21 % (natural pea dietary fibre) to 16.24 % ± 0.09 %. To further analyse the modification mechanism, the effects of three modification methods–superfine grinding (S), enzymatic modification (E), and superfine grinding combined with enzymatic modification (SE)–on the structural, physicochemical, and functional properties of pea SDF were studied. Nuclear magnetic resonance spectroscopy results showed that all four SDFs had α- and β-glycosidic bonds. Fourier transform infrared spectroscopy and X-ray diffraction spectroscopy results showed that the crystal structure of SE-SDF was most severely damaged. The Congo red experimental results showed that none of the four SDFs had a triple-helical structure. Scanning electron microscopy showed that SE-SDF had a looser structure and an obvious honeycomb structure than other SDFs. Thermogravimetric analysis, particle size, and zeta potential results showed that SE-SDF had the highest thermal stability, smallest particle size, and excellent solution stability compared with the other samples. The hydration properties showed that SE-SDF had the best water solubility capacity and water-holding capacity. All three modification methods (S, E, and SE) enhanced the sodium cholate adsorption capacity, cholesterol adsorption capacity, cation exchange capacity, and nitrite ion adsorption capacity of pea SDF. Among them, the SE modification had the greatest effect. This study showed that superfine grinding combined with enzymatic modification can effectively improve the SDF content and the physicochemical and functional properties of pea dietary fibre, which gives pea dietary fibre great application potential in functional foods.

Influence of Curing Temperature on the Performance of Calcined Coal Gangue-Limestone Blended Cements.

The utilization of calcined coal gangue (CCG) and limestone for the preparation of blended cement is an efficient approach to address the issue of coal gangue disposal. However, the compressive strength development of blended cement is slow, particularly at high substitution levels of CCG. Therefore, this study aimed to promote the hydration and mechanical properties of the calcined coal gangue-limestone blended cements by increasing the curing temperature. In this study, the samples were cured at two different temperatures, namely 20 and 40 °C. The four groups of samples contained 15 wt.%, 30 wt.%, 45 wt.% and 60 wt.% cement substitutions using CCG and limestone (2:1 mass ratio). The compressive strength, hydration and microstructure were investigated at the ages of 1 to 28 d. X-ray diffraction (XRD) and thermogravimetry (TG) were used to study the hydration behavior of samples. Mercury intrusion porosimetry (MIP) and scanning electron microscopy (SEM) were used to determine the microstructure of the samples. The results indicate that an increase in curing temperature significantly promotes the compressive strength of the calcined coal gangue-limestone blended cements from 1 to 28 d. The microstructural analysis indicates that increasing the curing temperature not only promotes cement hydration but also facilitates the reaction of CCG, which precipitated more hydrates such as C-A-S-H gel, Hc and Mc. These hydrates are conducive to refining the pore structures and densifying the microstructure, which sufficiently explains the enhanced compressive strength of the calcined coal gangue-limestone blended cements.

Influence of Eggshell Powder on the Properties of Cement-Based Materials.

Replacing cement with industrial by-products is an important way to achieve carbon neutrality in the cement industry. The purpose of this study is to evaluate the effect of eggshell powder on cement hydration properties, and to evaluate its feasibility as a substitute for cement. The substitution rates of eggshell powder are 0%, 7.5%, and 15%. Studying the heat of hydration and macroscopic properties can yield the following results. First: The cumulative heat of hydration based on each gram of cementitious material falls as the eggshell powder content rises. This is a result of the eggshell powder's diluting action. However, the cumulative heat of hydration per gram of cement rises due to the nucleation effect of the eggshell powder. Second: The compressive strengths of ES0, ES7.5, and ES15 samples at 28 days of age are 54.8, 43.4, and 35.5 MPa, respectively. Eggshell powder has a greater negative impact on the compressive strength. The effect of eggshell powder on the speed and intensity of ultrasonic waves has a similar trend. Third: As the eggshell powder content increases, the resistivity gradually decreases. In addition, we also characterize the microscopic properties of the slurry with added eggshell powder. X-ray Diffraction (XRD) shows that, as the age increases from 1 day to 28 days, hemicaboaluminate transforms into monocaboaluminate. As the content of the eggshell powder increases, FTIR analysis finds a slight decrease in the content of CSH. Similarly, thermogravimetric (TG) results also show a decrease in the production of calcium hydroxide. Although the additional nucleation effect of eggshell powder promotes cement hydration and generates more portlandite, it cannot offset the loss of portlandite caused by the decrease in cement. Last: A numerical hydration model is presented for cement-eggshell powder binary blends. The parameters of the hydration model are determined based on hydration heat normalized by cement mass. Moreover, the hydration heat until 28 days is calculated using the proposed model. The strength development of all specimens and all test ages can be expressed as an exponential function of hydration heat.

Deacetylated Konjac Glucomannan with a Slower Hydration Rate Delays Rice Digestion and Weakens Appetite Response.

The physical characteristics of chyme during gastrointestinal digestion are considered to significantly affect nutrient digestion and absorption (such as glucose diffusion), which has an impact on postprandial satiety. The present study aims to analyze the hydration rate (HR) and rheological properties of deacetylated konjac glucomannan (DKGM) at different degrees and then explore their effects on rice texture, digestive properties, and the subjects' post-meal appetite. The present results show that, as the deacetylation degree (DD) of KGM increased, the intersection point of the viscoelastic modulus shifted to a high shear rate frequency, and as the swelling time of the DKGM was prolonged, its HR decreased significantly. The results of the in vitro gastrointestinal digestion tests show that the hardness and chewability of the rice in the fast-hydration group (MK1) were remarkably reduced. In contrast, the slow-hydration group (MK5) exhibited an outstanding ability to resist digestion. The kinetics of starch hydrolysis revealed that the HR of the rice in the fast-hydration group was 1.8 times faster than that of the slow-hydration group. Moreover, it was found that the subjects' appetite after the meal was highly related to the HR of the MK. Their hunger (p < 0.001), desire to eat (p < 0.001), and prospective food consumption (p < 0.001) were significantly inhibited in the slow-hydration group (MK5) compared to the control. This study explored the nutritional effects of the hydration properties derived from the DKGM, which may contribute to modifying the high glycemic index food and provide ideas for the fabrication of food with enhanced satiating capacity.

Interlayer stress transfer improvement in bi-layer graphene oxide /calcium silicate hydrate via CNTs

Previous studies have shown that the experimental values of mechanical properties of graphene oxide/calcium silicate hydrate (GO/CSH) are lower than theoretical values. The strengthening degree of graphene oxide (GO) on mechanical properties of calcium silicate hydrate (CSH) is quite different. This is mainly due to the weak interface between GO layer and CSH matrix. In order to further enhance the interlayer stress transfer and interfacial interaction between GO and CSH nanostructures, a series of CNTs are created in double GO layers to form a new double GO/CSH with different number of CNTs configuration (D-GO-CNTs/CSH nanostructures). The results show that the normalized pull-out energies and normalized shear stress values of double GO/CSH with hydroxyl groups (D-GO-OH/CSH) composites are enhanced by 26.58% and 33.33%, while the normalized pull-out energies and normalized shear stress values of double GO/CSH with epoxy groups (D-GO-Oo/CSH) are only enhanced by 14.29% and 15.38%. In addition, the CNTs leads to a greatly enhancement (about 2–3 times) in normalized interlayer stress transfer of D-GO/CSH nanostructures, while exerts a little adverse effect (about 10%) on the failure strain of D-GO/CSH nanostructures. According strain energy ratio and molecular dynamics analysis, the enhancement effects of interlayer stress transfer in D-GO/CSH model are the best when the number of CNTs is 3. It provides a new approach for actively enhancing the interlayer stress transfer and interfacial interaction of D-GO/CSH nanostructures.

Combining raloxifene and mechanical loading improves bone composition and mechanical properties in a murine model of chronic kidney disease (CKD)

IntroductionPatients with chronic kidney disease (CKD) are at an alarming risk of fracture compared to age and sex-matched non-CKD individuals. Clinical and preclinical data highlight two key factors in CKD-induced skeletal fragility: cortical porosity and reduced matrix-level properties including bone hydration. Thus, strategies are needed to address these concerns to improve mechanical properties and ultimately lower fracture risk in CKD. We sought to evaluate the singular and combined effects of mechanical and pharmacological interventions on modulating porosity, bone hydration, and mechanical properties in CKD. MethodsSixteen-week-old male C57BL/6J mice underwent a 10-week CKD induction period via a 0.2 % adenine-laced casein-based diet (n = 48) or remained as non-CKD littermate controls (Con, n = 48). Following disease induction (26 weeks of age), n = 7 CKD and n = 7 Con were sacrificed (baseline cohort) to confirm a steady-state CKD state was achieved prior to the initiation of treatment. At 27 weeks of age, all remaining mice underwent right tibial loading to a maximum tensile strain of 2050 μƐ 3× a week for five weeks with the contralateral limb as a non-loaded control. Half of the mice (equal number CKD and Con) received subcutaneous injections of 0.5 mg/kg raloxifene (RAL) 5× a week, and the other half remained untreated (UN). Mice were sacrificed at 31 weeks of age. Serum biochemistries were performed, and bi-lateral tibiae were assessed for microarchitecture, whole bone and tissue level mechanical properties, and composition including bone hydration. ResultsRegardless of intervention, BUN and PTH were higher in CKD animals throughout the study. In CKD, the combined effects of loading and RAL were quantified as lower cortical porosity and improved mechanical, material, and compositional properties, including higher matrix-bound water. Loading was generally responsible for positive impacts in cortical geometry and structural mechanical properties, while RAL treatment improved some trabecular outcomes and material-level mechanical properties and was responsible for improvements in several compositional parameters. While control animals responded positively to loading, their bones were less impacted by the RAL treatment, showing no deformation, toughness, or bound water improvements which were all evident in CKD. Serum PTH levels were negatively correlated with matrix-bound water. DiscussionAn effective treatment program to improve fracture risk in CKD ideally focuses on the cortical bone and considers both cortical porosity and matrix properties. Loading-induced bone formation and mechanical improvements were observed across groups, and in the CKD cohort, this included lower cortical porosity. This study highlights that RAL treatment superimposed on active bone formation may be ideal for reducing skeletal complications in CKD by forming new bone with enhanced matrix properties.

Effects of polycarboxylate superplasticizer and hydroxypropyl methylcellulose on the properties of ferric-rich sulfoaluminate cement

Ferric-rich sulfoaluminate cement (FR-SAC) is a promising low-carbon cement and is usually used to prepare precast products due to its short setting time. However, the fast setting of FR-SAC paste also leads to its poor fluidity and workability. Polycarboxylate superplasticizer (PCE) and hydroxypropyl methylcellulose (HPMC) can improve the fluidity and viscosity but may affect other properties of FR-SAC products. To get a suitable performance of FR-SAC by adding PCE or HPMC, the properties of FR-SAC paste with PCE and HPMC added and their influence mechanism were explored. The results indicate that PCE adsorbs on the surface of positively charged ettringite in the slurry under the electrostatic attraction, which makes the negatively charged or uncharged FR-SAC particles uniformly dispersed in the slurry, thus regulating the rheology and other properties of FR-SAC paste. The compressive strength of FR-SAC paste increases with the increase of PCE addition. PCE slightly retard the early hydration rate of FR-SAC but does not affect the formation of later hydration products. Adding HPMC to FR-SAC paste can decrease the fluidity and increase the viscosity of FR-SAC paste but has little effect on its hydration properties. Therefore, when PCE and HPMC are used to modulate the rheology of FR-SAC paste, it is necessary to combine the utilization process and compressive strength requirements to keep both the rheological parameters and compressive strength in the suitable condition.

Molecular dynamics simulations to evaluate the decomposition properties of methane hydrate under different thermodynamic conditions

Understanding the thermodynamic effect on methane hydrate decomposition is beneficial for designing controllable methane recovery processes under conditions of continental margins and oceanic sediments. In this work, we systematically examined the effects of varying temperatures and pressures on the natural gas hydrate decomposition in the presence of 20 mol% methanol through the molecular dynamics approach. Taking advantages of key parameters of angular order parameter (AOP), radial distribution function (RDF), mean square displacement (MSD), and potential energy, we mainly aimed to explore the impact of temperature and pressure on the decomposition of methane hydrate. It can be founded that high temperature is a positive factor for the methane hydrate decomposition, and as the temperature increases from 272.15 K to 277.15 K, the promotion effect becomes more obvious, resulting in a reduction of decomposition time by 3.93 ns. On the contrary, pressure has a negative effect on the methane hydrate decomposition, and as the pressure increases from 1 bar to 200 bar, the inhibitory effect becomes smaller. Additionally, the potential energy as a function of time can be used to evaluate the decomposition rates under different thermodynamic conditions. The obtained results underscore the significant dependence of methane hydrate decomposition rates on temperature and pressure, providing essential guidelines for optimizing gas hydrate decomposition processes.

Engineered extracellular vesicle-based gene therapy for the treatment of discogenic back pain

Painful musculoskeletal disorders such as intervertebral disc (IVD) degeneration associated with chronic low back pain (termed “Discogenic back pain”, DBP), are a significant socio-economic burden worldwide and contribute to the growing opioid crisis. Yet there are very few if any successful interventions that can restore the tissue's structure and function while also addressing the symptomatic pain. Here we have developed a novel non-viral gene therapy, using engineered extracellular vesicles (eEVs) to deliver the developmental transcription factor FOXF1 to the degenerated IVD in an in vivo model. Injured IVDs treated with eEVs loaded with FOXF1 demonstrated robust sex-specific reductions in pain behaviors compared to control groups. Furthermore, significant restoration of IVD structure and function in animals treated with FOXF1 eEVs were observed, with significant increases in disc height, tissue hydration, proteoglycan content, and mechanical properties. This is the first study to successfully restore tissue function while modulating pain behaviors in an animal model of DBP using eEV-based non-viral delivery of transcription factor genes. Such a strategy can be readily translated to other painful musculoskeletal disorders.

Protonic ceramics Ba5In2–xYxAl2ZrO13 with the perovskite-related hexagonal structure for solid oxide fuel cells: Synthesis, optical band gap and transport properties

The solid solution Ba5In2–xYxAl2ZrO13 (0 ≤ х≤0.50) with hexagonal structure (space group P63/mmc) was prepared by the solid-state reaction method. The effects of isovalent Y3+-substitution on the structure, hydration, bandgap and transport properties have been investigated. The introduction of yttrium was accompanied by lattice expansion, which led to an increase in the concentration of protons during hydration. The doping did not lead to a significant increase in oxygen-ion conductivity since there was no change in oxygen stoichiometry. At the same time, doping led to an increase in ionic transport numbers due to a decrease in hole conductivity. Proton conductivity contribution and the values of proton conductivity increase with the increase in yttrium concentration. The phases with yttrium content x > 0.2 were predominant proton conductors at the temperature below 600°С under wet air.

The hydration and heavy metal immobilization performance of the CO2-active incineration fly ash-calcined clay-cement (CFC3) composite low-carbon cementitious system

CO2-active enhances the performance of municipal solid waste incineration fly ash as a supplementary cementitious material, increasing its utilization in cementitious systems. CFC3, a low-carbon cementitious material, effectively utilizes CO2-active incineration fly ash (CIFA). To minimize cement usage, the component effects on hydration need to be studied. In this study, hydration, mechanical and environmental properties of CFC3 were evaluated based on cement dosage and calcined clay/CIFA values. The maximum compressive strength of the samples reached 18.0 MPa at 3d and 47.6 MPa at 56d. The introduction of CIFA delayed the reactions of C3S and aluminates. Calcined clay contributes to improved gel polymerization, optimizes the Si/AlCASH ratio, and refines pore structure. A decrease in cement content increased in the aluminate phases, making monocarbonate the primary hydration product. The results of leaching tests indicated that Cd and Pb in R2C50 were transformed into non-leachable, inactive substances. Demonstrating the environmental friendliness of CFC3.

Performances of concrete with binder and/or aggregates replacement by all-solid waste materials

Aiming for an all-solid waste concrete, a quaternary solid waste binder (SWBs) system comprising blast furnace slag, fly ash, desulfurization gypsum, and Bayer red mud was developed and utilized for both binders and preparation of cold bonded artificial aggregates. The first section investigated and discussed the hydration properties and strength gain mechanism of SWBs, revealing that ettringite formation and growth contribute to early age strength development of SWBs, while C-A-S-H formation contributes significantly to the later strength gain. The second section systematically studied the concrete performances, including mechanical properties, shrinkage, chlorides, and seawater resistance. An all-solid waste-based concrete strategy was presented by gradually substituting cement and natural aggregates. It was observed that SWBs-based concrete exhibited significantly lower shrinkage and excellent chloride ion resistance, although slightly lower mechanical properties were observed. The solid waste-based artificial aggregates proved viable alternatives to natural rock aggregates in low-strength concrete classes. Incorporating artificial aggregates endowed the concrete with self-curing properties and reduced its shrinkage and chloride migration, with only a minor effect on its mechanical strength. Lastly, an all-solid waste concrete combining the characteristics of SWBs and cold-bonded artificial aggregates was achieved. The resulting concrete exhibited lower shrinkage and excellent chloride and seawater resistance. This study provides a reference for designing and developing solid waste-based binders and concrete.

Synergy of Hydration and Microstructural Properties of Sustainable Cement Mortar Supplemented with Industrial By-Products

Synergy of Hydration and Microstructural Properties of Sustainable Cement Mortar Supplemented with Industrial By-Products

Improved hydration property of tissue adhesive/hemostatic microparticle based on hydrophobically-modified Alaska pollock gelatin

The management of bleeding is an important aspect of endoscopic surgery to avoid excessive blood loss and minimize pain. In clinical settings, sprayable hemostatic particles are used for their easy delivery, adaptability to irregular shapes, and rapid hydration. However, conventional hemostatic particles present challenges associated with tissue adhesion. In a previous study, we reported tissue adhesive microparticles (C10-sa-MPs) derived from Alaska pollock gelatin modified with decyl groups (C10-sa-ApGltn) using secondary amines as linkages. The C10-sa-MPs adhere to soft tissues through a hydration mechanism. However, their application as a hemostatic agent was limited by their long hydration times, attributed to their high hydrophobicity. In this study, we present a new type microparticle, C10-am-MPs, synthesized by incorporating decanoyl group modifications into ApGltn (C10-am-ApGltn), using amide bonds as linkages. C10-am-MPs exhibited enhanced hydration characteristics compared to C10-sa-MPs, attributed to superior water absorption facilitated by amide bonds rather than secondary amines. Furthermore, C10-am-MPs demonstrated comparable tissue adhesion properties and underwater adhesion stability to C10-sa-MPs. Notably, C10-am-MPs exhibited accelerated blood coagulation in vitro compared to C10-sa-MPs. The application of C10-am-MPs in an in vivo rat liver hemorrhage model resulted in a hemostatic effect comparable to a commercially available hemostatic particle. These findings highlight the potential utility of C10-am-MPs as an effective hemostatic agent for endoscopic procedures and surgical interventions.