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Due to frequent petrochemical spills, environmental pollution and the threat of secondary marine fires have arisen, necessitating an urgent need for petrochemical spill treatment strategies with high-performance oil-water separation capabilities. To address the challenges of poor durability, instability in hydrophobic conditions, and difficulty in absorbing high-viscosity crude oil associated with hydrophobic absorbent materials, the authors of this study took inspiration from the unique micro and nanostructures of springtails' water-repellent skin. We engineered a superhydrophobic melamine sponge using interfacial assembly techniques designated as Si@PBA@PDA@MS. This material demonstrated improved mechanical and chemical durability, enhanced photothermal performance, and reduced fire risk. The metal-organic framework (MOF)-derived cobalt-iron Prussian blue analog (CoFe-PBA) was firmly anchored to the sponge framework by the chelation of cobalt ions using polydopamine (PDA). The results demonstrated that Si@PBA@PDA@MS demonstrated excellent superhydrophobicity (WCA=163.5°) and oil absorption capacity (53.4-97.5 g/g), maintaining high durability even after 20 cycles of absorption-squeezing. Additionally, it could still exhibit excellent mechanical properties, hydrophobic stability, and absorption performance across a wide temperature range (0-100 °C), pH range (1-14), and high compression strength (ε = 80%), with excellent mechanical/chemical durability. Furthermore, Si@PBA@PDA@MS demonstrated remarkable photothermal performance and low fire risk, offering efficient, safe, and sustainable practical value for effective petrochemical spill treatment.

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A series of 56P2O5-7.5Al2O3-5.9BaO-(28.56-x)K2O-xNa2O-1.51Nd2O3 phosphate glasses with different Na/(Na+K) ratios, which were specially designed for high-power laser application, were prepared by a high-temperature melting method. Except for the density, refractive index, glass transition temperature, and DC conductivity, the chemical durability and spectral properties, as emphasized by high-power and high-energy laser material, were further measured and analyzed. Regarding the chemical durability, the dissolution rates of these glasses do not show an evident mixed alkali effect with increasing the Na/(Na+K) ratio, although the effect is obvious for the glass transition temperature and DC conductivity. To better understand the nature of the dissolution mechanism, the ionic release concentrations of every element are determined. Both Na and K undergo ion exchange, but the ion exchange rate of K is much larger than that of Na. In terms of the spectral properties, the J-O parameters, emission cross-section, radiation lifetime, fluorescence lifetime, effective bandwidth, fluorescence branching ratio, and quantum efficiency are determined from absorption and emission spectra. The trend of Ω2 deviating from linearity indicates that the coordination environment symmetry of Nd3+ ions and the covalence of Nd-O also present an evident mixed alkali effect. The most important finding is that the emission cross-section and fluorescence lifetime of Nd3+ ions at 1053 nm were not affected by the change in the Na/K ratio. According to the above experimental results, the optimized value of the Na/K ratio was determined, based on which the 56P2O5-7.5Al2O3-5.9BaO-(28.56-x)K2O-xNa2O-1.51Nd2O3 glass maintains a high emission cross-section with good chemical durability.

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This study focused on the production and characterization of phosphate glass fibers (PGF) for application as composite reinforcement. Phosphate glasses belonging to the system 52P2O524CaO13MgO (11-(X + Y)) K2OXFe2O3YTiO2 (X:1, 3, 5) and (Y:0.5, 1) were elaborated and converted to phosphate glass fibers. First, their mechanical properties and chemical durability were investigated. Then, the optimized PGF compositions were used afterward as reinforcement for thermosetting composite materials. Polyester matrices reinforced with short phosphate glass fibers (sPGF) up to 20 wt % were manufactured by the contact molding process. The mechanical and morphological properties of different sPGF-reinforced polyester systems were evaluated. The choice between the different phosphate-based glass syntheses (PGFs) was determined by their superior mechanical performance, their interesting chemical durability, and their high level of dispersion in the polyester matrix without any ad sizing as proven by SEM morphological analysis. Moreover, the characterization of mechanical properties revealed that the tensile and flexural moduli of the developed polyester-based composites were improved by increasing the sPGF content in the polymer matrix in perfect agreement with Takayanagi model predictions. The present work thus highlights some promising results to obtain high-quality phosphate glass fiber-reinforced polyester parts which can be transposed to other thermosetting or thermoplastic-based composites for high-value applications.

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In order to find a rapid, efficient, safe and reliable treatment technology for radioactive contaminated soil, the microwave sintering method was used to sinter the simulated radioactive contaminated soil with different CeO2 content at 1100 °C, 1200 °C and 1300 °C for 30 min to achieve vitrification. The phase, microstructure, morphology, mechanical properties, and chemical durability of the sintered samples were investigated. XRD and SEM-EDS results showed that Ce4+ did not participate in the formation of the glass network, but was fixed in the glass network structure. The amorphous fraction of the samples sintered at 1300 °C can reach up to 98%. EDS results showed that the element distribution was uniform. In addition, the density and hardness values of the sintered matrices were in the range of 1.875-2.543 g/cm3 and 6.667-7.112 GPa, respectively. Our results show that the density and hardness values are related to the sintering temperature and CeO2 content. The normalized leaching rate of Ce in samples reached 10-7 g/(m2·d) after 28 d.

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A superhydrophobic surface was achieved using a monolayer of the perpendicularly oriented epoxy-silica@polydivinylbenzene (PDVB) Janus particles (JPs) on an epoxy resin substrate. The epoxy-silica@PDVB JPs were synthesized from the silica@PDVB/polystyrene (PS) JPs through selective etching of the PDVB/PS belly and the surface modification of the silica part. The modified silica parts can be covalently bonded with the epoxy resin to make the perpendicular orientation spontaneous as well as the coating more robust. The outward PDVB bellies can constitute the micro-/nanoscale hierarchical structures for the superhydrophobic property. The superhydrophobic coating exhibits water repellence and self-cleaning properties. Moreover, the coating exhibits good chemical durability that it can keep the superhydrophobic property after long-time immersion in various aqueous solutions and organic solvents. The coating is still superhydrophobic after water flushing and mechanical wearing, showing the perfect mechanical durability.

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Advanced materials and processes are required to separate halides and fission products from complex salt waste streams associated with the chemical reprocessing of used nuclear fuels and molten salt reactor technologies for immobilization into chemically durable waste forms. In this work, we explore an innovative concept using metal halide perovskites as advanced host phases to incorporate Cs and Cl with very high waste loadings. Wet chemistry-synthesized Cs2SnCl6 powders from CsCl salt solutions are successfully encapsulated into a silica matrix to form a composite using low-temperature spark plasma sintering with tunable Cs and Cl loadings up to 31 and 26 wt %, respectively. Chemical durability testing of the composite waste forms by semi-dynamic leaching experiments demonstrates that an incongruent leaching mechanism dominates the release of Cs and Cl. The metal halide perovskite-silica composite waste forms display exceptional chemical durability with the long-term release rates of Cs and Cl comparable to or outperforming the state-of-the-art waste form materials but with significantly higher waste loadings. The scalable synthesis of the metal halide perovskite from wet chemistry processes opens up new opportunities in designing advanced waste forms for salt wastes with very high waste loadings and exceptional chemical durability for the sustainable development of advanced fuel cycles and next-generation reactor technologies.

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Four different phosphate glass formulations (F0, F1, F2, and F3) were developed according o wheat nutrient requirements to be used as controlled-release fertilizers. These glasses contain macro-elements (P2O5-K2O-CaO-MgO), with the addition of microelements (Fe-Mn-Zn-B-Cu-Mo) in each formulation. The effects of these elements' addition on thermal properties, glass structure, and dissolution behaviors were investigated. Results showed that these glasses are composed essentially of metaphosphate chains and that the addition of micronutrients could change the chemical durability of phosphate glasses. A greenhouse experiment was performed using wheat (Triticum durum L.) to evaluate the efficiency of the four glasses, with or without application of chemical nitrogen (N) (N + VF and VF, respectively). The different formulas were tested using two rates of 0.3 and 1 g per plant. In addition to the vitreous fertilizer formulations, two other treatments were applied: control treatment with no amendment and Nitrogen-Phosphorus-Potassium treatment with the application of the conventional fertilizers on the base of optimal rates. After four months of cultivation, vitreous fertilizers application significantly improved growth (7% to 88%), photosynthetic (8% to 49%) parameters, and yield (29% to 33%) compared to NPK treatment and to the control. It has been found that formulas F1, F2, and F3 may constitute a potential alternative to conventional fertilization due to their positive impact on wheat production and can be used in practice as an environmentally controlled-release fertilizer.

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Basalt continuous fibers (BFs) have been widely applied in the construction industry including marine applications, however, the corrosion mechanism of BFs in a seawater environment is still not well understood. In this work, we explored the effect of the seawater environment on the weight loss, tensile strength, surface morphology, and microstructure structure of BFs via soaking the BFs in seawater solutions at different temperatures and durations. Results show that the weight loss ratio of BFs decreases at the first stage (around 18 h) of soaking at 80 °C, 85 °C, and 90 °C and then increases for longer soaking durations, while the tensile strength has the opposite change. This enhancement of tensile strength and chemical resistance (at the first stage of seawater soaking) is dominated by the ion-exchange induced 'blunting' mechanism, even though the results from a Fourier transform infrared (FT-IR) spectrometer and energy-dispersive spectroscopy (EDS) revealed the damaging of the Si-O-Si tetrahedral structure during the corrosion process. This work revealed the full corrosion process and corresponding mechanism of BFs in a seawater environment.

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The sustainable development of civil nuclear energy requires the fabrication of the durable nuclear wasteforms, in particular for high-level radioactive waste, which involves the design of the composition and microstructure. Herein, we demonstrated that high-entropy ceramics (Eu1-xGdx)2(Ti0.2Zr0.2Hf0.2Nb0.2Ce0.2)2O7 are the potential candidate as immobilizing hosts for high-level radioactive waste. The static aqueous leaching test indicates that the normalized leaching rates for the simulated radionuclides Ce (LRCe) and Gd (LRGd) in as-prepared high-entropy ceramics are approximately 10-6~10-8 g·m-2·d-1 after 42 days testing, much lower than those reported values in doped-Gd2Zr2O7 (10-6~10-3 g·m-2·d-1). The excellent chemical durability is mainly due to the synergistic effects of the compositional complexity and severe lattice distortion. Compared to their ternary oxides, the low oxygen vacancy concentration slows down the migration and diffusion of cations. Moreover, the lattice distortion increases the lattice potential energy, also inhibiting the migration of cations. This study provides a strategy for the development and application of high-entropy ceramics as the wasteforms.

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Ion exchange materials are used widely for the removal of radionuclides from contaminated water at nuclear licensed sites, during normal operating procedures, decommissioning and in accident clean-up, such as the ongoing recovery operation at the Fukushima Daiichi nuclear power plant. Framework silicate inorganic ion exchange materials, such as chabazite ((Na0.14K1.03Ca1.00Mg0.17)[Al3.36Si8.53O24]•9.7H2O), have shown particular selectivity towards 137Cs uptake, but their safe storage poses a number challenges requiring conditioning into passively safe waste packages of minimal volume. We demonstrate the transformation of Cs-exchanged chabazite into a glass-ceramic wasteform by hot isostatic pressing to produce a durable consolidated monolith. The application of heat and pressure resulted in the collapse of the chabazite framework, forming crystalline Cs-substituted leucite (Cs0.15(3)K0.57(4)Al0.90(4)Si2.24(5)O6) incorporated within a K2O-CaO-MgO-Al2O3-SiO2 glass. The Cs partitioned preferentially into the Cs/K-feldspar which incorporated ~77% of the Cs2O inventory. Analysis of the chemical durability of the glass-ceramic wasteform revealed that the Cs release rates were comparable or lower than those reported for vitrified high level and intermediate level wastes. Overall, hot isostatic pressing was demonstrated to be an effective processing technology for conditioning spent inorganic ion exchange materials by yielding durable and passively safe wasteforms.

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Regenerated Silk Fibroin (RSF) films are considered promising substrate candidates primarily in the field of bio-integrated electronic device applications. The key issues that ought to be addressed to exploit the inherent advantages of silk thin films include enhancing their flexibility and chemical durability. Such films find a plethora of applications, the significant one being conformal, transparent microelectrode arrays. Elevated temperatures that are regularly used in lithographic processes tend to dehydrate RSF films, making them brittle. Furthermore, the solvents/etchants used in typical device fabrication results in the formation of micro-cracks. This paper addressed both these issues by developing composite films and studying the effect of biodegradable additives in enhancing flexibility and chemical durability without compromising on optical transparency and surface smoothness. Through our rigorous experimentation, regenerated silk blended with Polyvinyl Alcohol (Silk/PVA) is identified as the composite for achieving the objectives. Furthermore, the Cyto-compatibility studies suggest that Silk/PVA, along with all other silk composites, have shown above 80% cell viability, as verified using L929 fibroblast cell lines. Going a step further, we demonstrated the successful patterning of 32 channel optically transparent microelectrode array (MEA) pattern, with a minimum feature size of 5 µm above the free-standing and optically transparent Silk/PVA composite film.

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In the field of radioactive waste immobilization, the investigation of irradiation stability is of considerable importance. In this study, uranium-contaminated soil samples were irradiated by 1.5 MeV Xe20+ ions with fluences ranging from 1 × 1012 to 1 × 1015 ions/cm2. Xe20+ heavy-ion radiation was used to simulate the self-irradiation of actinide nuclides. The uranium-contaminated soil samples were sintered via microwaves. Grazing incidence X-ray diffraction results showed that irradiation can cause crystallization of the sample. After irradiation, the Vickers hardness of the samples decreased slightly. Comparative analysis showed that the sample had good radiation resistance, and the leaching rate (28 d) of the sample increased slightly after irradiation, but the overall performance was stable. Our investigation reveals the corresponding mechanism of uranium-contaminated soil irradiation of 1.5 MeV Xe20+ ions.

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Consecutive microwave sintering is a method proposed in this study to dispose soil contaminated by Sr during a nuclear accident by rapidly solidifying the contaminated soil. The results show that soil contaminated with 20 wt% SrSO4 and 30 wt% SrSO4 can be completely solidified by microwave sintering at 1100-1200 and 1300 â„ƒ, respectively, for 30 min. Sr was found to be cured into slawsonite (SrAl2Si2O8) and glass structures. Moreover, soil sintered at 1300 â„ƒ has large cured solubility (30 wt.%), good uniformity, and excellent hardness (6.9-7.2 GPa) and chemical durability (below 1.46 × 10-5 g m-2 d-1 at 28 d). Thus, consecutive microwave sintering technology may provide a new method for treating Sr-contaminated soil in case of a nuclear accident emergency.

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Previous studies on chemical durability of radioactive waste forms mainly focused on samples containing no radionuclides. We performed a hydrothermal experiment with several variably self-irradiated natural titanites and the leaching results indicate that radiation damage has some influence over chemical durability through its ability to change the microstructures of materials, including cracks, holes, interconnected amorphous clusters, and nano-sized defects. However, chemical durability is not influenced if the variation in local microstructures induced by radiation damage is insignificant.

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To improve both the mechanical and chemical durability of Nafion membranes for polymer electrolyte membrane fuel-cells (PEMFCs), Nafion composite membranes containing sulfonated graphene oxide (SGO) and cerium oxide (CeO2; ceria) were prepared by solution casting. The structure and chemical composition of SGO were investigated by FT-IR and XPS. The effect of the sulfonation, addition of SGO and ceria on the mechanical properties, proton conductivity, and chemical stability were evaluated. The addition of SGO gave rise to an increase in the number of sulfonic acid groups in Nafion, resulting in a higher tensile strength and proton conductivity compared to that of graphene oxide (GO). Although the addition of ceria was found to decrease the tensile strength and proton conductivity, Nafion/SGO/ceria composite membranes exhibited a higher tensile strength and proton conductivity than recast Nafion. Measurement of the weight loss and SEM observations of the composite membranes after immersing in Fenton's reagent indicate an excellent radical scavenging ability of ceria under radical degradation conditions.

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Phosphate glasses have potentially interesting properties that can be used in various applications. Recently, different studies are focusing on their dissolution behaviours that can be modified to suit some environmental applications, such as controlled-release fertilisers. In this work, magnesium had been suggested to improve the glass durability of 3P2O5-2K2O-(1 - x)CaO-xMgO glasses (0 ≤ x ≤ 1). Indeed, its effect on glass structure, thermal properties and most important dissolution behaviours were studied, in order to evaluate their suitability of being used as controlled-release fertilisers. Various compositions in which calcium was partially replaced by magnesium were prepared by melting at 800 °C. The samples were characterised by differential scanning calorimetry, density measurements, X-Ray diffraction, FTIR spectroscopy and Raman spectroscopy. The dissolution behaviours were investigated using inductively coupled plasma optical emission spectrometry ICP-OES, pH measurements and SEM. Substitution of calcium by magnesium reduced the glass density, owing to the lower atomic weight of magnesium compared to calcium, and caused an increase in glass transition and crystallisation temperatures. Magnesium substitution significantly improved the chemical durability of the glasses due to more covalent Mg-O bond than the Ca-O bond. This study demonstrated that 3P2O5-2K2O-0.3CaO-0.7MgO (x = 0.7) had a dissolution profile adequate to the criteria of controlled-release fertilisers and could be used to nourish the plants with phosphorus, potassium, calcium and magnesium.

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Reprocessed high-level nuclear waste (HLW) contains range of radioactive components. Crystalline oxyphosphate apatite ceramic of the formula LaSr4(PO4)3O [LSS] was investigated as a host for HLW immobilisation. The systematic study of solid solubility limit of individual rare earth ion substitution leads to the formulation of simulated wasteform of the formula La0.6Pr0.1Nd0.1Sm0.1Gd0.1Sr4(PO4)3O (WF1) with the waste loading of 17.95 wt% of rare-earth ions. Both parent and WF1 were synthesized by precipitation method. The thermal stress and groundwater inventory at the repository site can severely affect the wasteform performance, in addition to radiation and mechanical effects. Hence, the fabricated composition with high-level nuclear waste loading must be screened basically for chemical, thermal and radiation resistance. The present study investigated the thermal stability (by TGA), thermal expansion behaviour (by HT-XRD) and chemical durability (MCC-5) of the composition (WF1). The weight loss of WF1 being 2.2% and the average thermal expansion co-efficient (αavg) of 10.7 ± 1.2 × 10-6 K-1 in the temperature range (298-973 K) were comparatively lower than the parent phase, LaSr4(PO4)3O. The WF1 showed resistance to leaching of RE3+ and P5+ with only the leaching of Sr2+ ion whose leach rate was of the order 10-3-10-4 gm-2d-1.

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This review describes low temperature degradation (LTD), discoloration, and erosion of high translucent dental zirconia and discusses its chemical durability in comparison with other CAD/CAM materials. The LTD of zirconia strongly depended on the firing temperature, yttria content, surface treatment, and heat treatment. Glass ceramics for CAD/CAM were remarkably etched in a lactic acid at 60°C, KOH solution at 60°C, and saline solution at 90°C, whereas zirconia showed no changes in these solutions. Glass ceramics and hybrid resins for CAD/CAM showed significant discoloration in a red wine and rhodamine B solution at 37°C, whereas zirconia showed no discolorations in either solution. It was concluded that high translucent dental zirconia has the highest chemical durability among dental CAD/CAM materials.

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Basalt glass belongs to the iron-rich aluminosilicate glass system; thus, the iron content and the iron redox index (IRI=Fe2+/Fetotal) influence the viscosity, density, mechanical and chemical properties of basalt fiber (BF). In this work, continuous BFs with IRIs ranging from 0.21-0.87 were prepared by adding a different amount of redox agents. An economical and easily accessible testing method-the spectral photometric method with 1,10-phenanthroline-is applied to measure the IRI with convinced accuracy, which has been approved by Mössbauer spectra and X-ray fluorescence analysis. The tensile strength of the BF samples increases approximately linearly with increasing IRI as a function of σ = 227.9 IRI + 780.0 . The FT-IR results indicate that, with increasing IRI, the ferric ions are replaced by the much stronger network formers (Al3+ and Si4+), hence the increased the tensile strength. The X-ray diffraction results show an amorphous nature of BF samples. Moreover, the tensile strength is significantly decreased after the alkali corrosion, which is partly attributed to the severe surface damaging according to the SEM results. This work proved the feasibility of mechanical property improvement in BF production by controlling the iron redox index.

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Corrosion-protective surfaces are of the utmost relevance to ensure long-term stability and reliability of metals and alloys by limiting their interactions with corrosive species, such as water and ions. However, their practical applications are often limited either by the inability to repel low surface tension liquids such as oils and alcohols or by poor mechanical durability. Here, a superomniphobic surface is reported that can display very high contact angles for both high and low surface tension liquids as well as for concentrated acids and bases. Such extreme repellency allowed for approximately 20% of the corrosion rate compared to the conventional superhydrophobic corrosion protective coatings. Furthermore, the superomniphobic surface can autonomously repair mechanical damage at an elevated temperature (60 °C) within a short period of time (60 s), and the surface can restore its intrinsic corrosion protection performance. Such superomniphobic surfaces thus offer a wide range of potential applications, including pipelines, with sustainable corrosion protection and rust inhibitors for steel in reinforced concrete.