Additive Manufacturing (AM), also known as 3D printing, is widely used due to its advantages such as high design freedom, no need for molds, mass customization, and the ability to construct complex shaped components. The existing 3D printing methods are developed, among which DLP technology has the advantages of fast printing speed, high dimensional accuracy, no need for molds, close to net shape, and high mechanical performance. Ceramic materials are widely used as high-temperature structural functional materials due to their high temperature resistance, oxidation resistance, corrosion resistance, and mechanical properties. However, compared with metal and polymer materials, ceramic materials are still immature in 3D print processing, facing some problems such as limited availability of suitable raw materials, difficulty in optimizing ratios, high costs, poor process stability, and limited mechanical properties. To overcome the problems above, combining photopolymerization 3D printing with ceramic sintering technology becomes an effective method. In this study, ceramic powder and photosensitive preceramic were ground to obtain a uniform slurry with a good flowability, and then high-precision green bodies were formed through DLP.

Polysilazane PSZ-ViH containing both vinyl and Si-H was prepared via ammonified of trimethylchlorosilane, methyltrichlorosilane, methylvinyldichlorosilane, and methylhydrogendichlorosilane. Referring to the reaction conditions above, a Vi-terminated/Si-H containing polysilazane PSZ-TViH was obtained with dimethylvinylchlorosilane, methyltrichlorosilane, and methyldichlorosilane as raw materials. Si-H containing polysilazane LSZ-H was obtained with trimethylchlorosilane, methyltrichlorosilane, and methyldichlorosilane as raw materials. When 2-isocyanatoethyl acrylate (ICA) was used as a modifier, the reaction occurred under stirring in dark conditions at room temperature for 24 h. 2,4,6-trimethylbenzoyl phenyl phosphonic acid ethyl ester (TPO-L) was added as a photosensitizer and stirred in dark conditions for 10 min. PSZ-ViH and Si₃N₄ powders with different mass fractions were ground, ICA and TMPTA were added, and then followed by TPO-L. Finally, a photosensitive polysilazane-based ceramic slurry was obtained after stirring in the dark for 10 min.

The photosensitive slurry was photo-cured and formed on the DLP printer Photon Mono 4k. The infrared spectra were determined by Fourier transform infrared spectroscopy (FT-IR). The curing thickness of photosensitive resin or slurry at different exposure durations was measured on a coating thickness gauge (HC622) by an iron-based F probe and an iron reference block. The rheological properties of photosensitive slurries were characterized by a rotary rheometer (DESKTOP BKLJ9S3), with steady-state shear rate scanning at room temperature and dynamic temperature, respectively. The thermo-behavior was characterized by differential scanning calorimetry (DSC) on a model Mettler Toledo DSC1 Q2000 thermal analyzer, and thermogravimetric analysis (TGA) on a model Discovery TGA 55 thermal analyzer with an argon gas flow rate of 40 mL/min and a heating rate of 10 ℃/min, respectively. The density of photo-cured printed parts was measured by the Archimede displacement method. The cross-sectional morphology of the material was characterized by field emission scanning electron microscopy (FESEM, Hitachi S4800), and the sample (ion sputter coated Pd layer) was fixed on the sample stage with conductive adhesive at an acceleration voltage of 5 kV and a vacuum degree of ≤ 10^-4 Pa.

PSZ-ViH with vinyl as side groups can be chemically modified with 2-Isocyanatoethylacrylate, and PSZ-ViH-ICA shows the maximum light-curing depth compared with PSZ-TViH-ICA and PSZ-H-ICA. Liquid photoinitiator TPO-L can equilibrate light reactivity and shelf-life via optimizing the TPO-L amount, leading to a good balance of transition depth (D_p=63.09 μm) and threshold exposure intensity (E_c=3.94 mJ/cm²). As a result, TPO-L can be chosen as a suitable photoinitiator in DLP processing for polysilazane slurry. Among the ceramic powders introduced in the slurry, the light-curing depth follows an order of SiO₂>Al₂O₃ > ZrO₂ > Si₃N₄ > AlN. SiC slurry shows a low light-curing depth, while ZrB₂ slurry cannot be light cured totally. Silicon nitride powder is applied as a slurry additive due to the proper light-curing depth and similar chemical components compared with polysilazane adhesive. Ideal light reactivity and higher material density can be realized by synergistic effect of combination addition of micro-sized and nano-sized Si₃N₄. Based on the model of the relationship between transition depth (D_p) and threshold exposure intensity (E_c), the processing parameters are determined (i.e., the layer width is 2/3 of transition depth, the exposure time is adjusted according to three times of threshold exposure intensity). DLP pringting with a high precision of polysilazane slurry can be realized for the production of complex structures (e.g., cellular structure). An interlayered adhesion occurs and the width of single layer is almostly equal to the setting value via analyzing the fracture morphology of light-curing samples with different powder contents and particle sizes.

The distribution of vinyl groups in polysilazane molecules significantly affected the crosslinking density and curing depth. Polysilazane PSZ-ViH containing vinyl side groups had a larger photopolymerization thickness than PSZ-TViH with terminated vinyl groups due to the uniform distribution of active sites in the former.

The photosensitizer screening experiment showed that liquid 2,4,6-trimethylbenzoyl phosphate ethyl ester TPO-L balanced the photo-curing activity and storage stability. The balance between transmission depth and critical exposure intensity could be achieved via optimizing the TPO-L dosage, making it a suitable photosensitizer for polysilazane slurry.

Oxide/nitride powders (such as SiO₂ and Si₃N₄) could ensure a light penetration due to their low refractive index and light color, while carbide/boride powders (such as SiC and ZrB₂) could suffer from severe light attenuation due to their high refractive index and dark color. The density of the photocured sample increased to 1.19 g/cm³ via mixing nano-/micro-sized ceramic powders (i.e., 5% 2 μm Si₃N₄ and 5% 20 nm Si₃N₄), and reducing the light scattering loss (i.e., transmission depth 52.80 μm), which verified the feasibility of micro-/nano-sized synergy in photosensitive polysilazane slurry.

Based on the theoretical model of transmission depth D_p and critical exposure intensity E_c, the processing parameters in DLP were proposed, i.e., the layer thickness was set at 2/3 of the transmission depth (h=2D_p/3), and the exposure time was calibrated to equal to three times of the energy of the critical exposure intensity (t=3E_c/I), thus achieving a high-precision DLP printing of complex structures such as honeycomb.

This study systematically analyzed the chemical composition, phase, firing temperature and atmosphere of Han Dynasty lead glazed pottery unearthed from the Yangguanzhai Site, China, through X-ray fluorescence spectrometer (XRF), X-ray diffractometer (XRD), Raman spectrometer (Raman), thermal expansion meter, X-ray photoelectron spectrometer (XPS), etc., and explored its raw material composition and firing process. The results show that the chemical composition and phase of all sample bodies are similar to those of the clay in the burial area of the Yangguanzhai site, so the raw materials used for making the bodies are all local clay. The glaze colors are divided into three types, i.e., yellow, green and yellow-green. The yellow glaze mainly uses Fe₂O₃ provided by the clay for making the body as a coloring agent, while the green glaze mainly uses CuO provided by bronze as a coloring agent. The content of Fe₂O₃ and CuO in the yellow-green glaze is between the two. Because the melting point of clay is higher than that of bronze, yellow glaze needs to increase lead-rich raw materials and reduce silicon-rich raw materials to lower the melting temperature of the glaze, resulting in yellow glaze showing the characteristic of "high lead and low silicon", while green glaze is the opposite, with yellow-green glaze lying between the two. Although there are differences in the types of colorants and glaze formulas, the samples of the three glaze colors are all fired in an oxidizing atmosphere at the firing temperatures controlled at 850-950 ℃.

In this study, we analyzed the chemical composition and phase composition of the body and glaze in 29 samples to investigate their raw materials and firing techniques by XRF, XRD, Raman spectroscopy, and other techniques.

Based on the colorimetric parameter analysis of glaze samples, they can be categorized into three types, i.e., yellow, green, and yellow-green. The saturation (C*) of yellow and yellow-green glazes exhibits a significant variation, while green glazes show a greater consistency. This variation is correlated to the types and concentrations of colorants in the glazes. The body color is uniform and stable, with coloration primarily influenced by saturation. All the body samples are colored with Fe₂O₃ and TiO₂, exhibiting the similar chemical compositions and phase characteristics. This indicates that the body material likely originates from the same type of common, easily fusible clay, presumably sourced from the Yangguanzhai site. The chemical composition of the glaze layers reveals that yellow glazes have the lowest SiO₂ content and the highest PbO content, while green glazes exhibit the opposite pattern. This may be related to coloration requirements and the fluxing effect of PbO. The coloring agents originate from bronze, and the glaze materials incorporate clay from the body production process as an iron source. The XRD patterns and Raman spectra further confirm the presence of quartz, feldspar, mica, and hematite phases in both body and glaze. The XPS analysis reveals Fe³⁺ as the predominant iron species. Combined with thermal expansion measurements indicating firing temperatures at 850-950 ℃, these results collectively confirm the samples are fired in an oxidizing atmosphere.

The lead-glazed pottery bodies of the Han Dynasty could be brick red in color, with Fe₂O₃ and TiO₂ as colorants. Their chemical composition and phase were highly consistent with the clay of the site, and the components of the bodies with different glaze colors were similar. They had the characteristics of common fusing clay, indicating that the raw materials for making the bodies were taken from the local soil and fired locally. The lead glazed pottery of the Han Dynasty haf three glaze colors, i.e., yellow, green and yellowish-green. The yellow glaze mainly usef Fe₂O₃ as the main colorant, while the green glaze mainly used CuO. The content of Fe₂O₃ and CuO in the yellowish-green glaze was between the two. Since the correlation of Fe₂O₃-TiO₂ in the body and glaze was consistent, and hematite appeared in both glazes, indicating that the clay used for making the body was used as the iron source during glaze production. There could be a positive correlation between CuO and SnO₂ in the glaze, indicating that CuO originated from bronze. Because the melting point of clay was higher than that of bronze, the required PbO content was also higher. Therefore, yellow glaze showed the characteristics of low silicon and high lead, and was prone to "silver glaze" diseases. However, the correlation between SiO₂ and Al₂O₃ in the body and glaze was inconsistent, indicating that silicon-rich raw materials such as quartz sand were added to the glaze. The lead-glazed pottery of the Han Dynasty was all fired in an oxidizing atmosphere, with the firing temperature controlled at 850-950 ℃. The analysis showed that although there were differences in glaze colors, the similar process conditions were adopted for the firing temperature and atmosphere.

This review summarizes recent research on the preparation of Si—O—C ceramic composite absorbing materials by a precursor conversion method from multiple aspects. Particle reinforced Si—O—C ceramics suppress the volume shrinkage of sintered products and improve the yield of ceramics. Porous Si—O—C ceramics cause multiple reflections of electromagnetic waves entering the interior of the material, prolonging the propagation path and helping to improve impedance matching. Introducing heterogeneous element M into Si—O—C ceramics can alter the phase separation and crystallization behavior, and improve the thermal stability of Si—O—C ceramics. Fiber reinforced Si—O—C ceramics achieve a structural and functional integration. However, the manufacturing accuracy of complex structures is limited, and traditional mechanical processing is difficult to achieve high-precision forming of complex lattice structures. Porous Si—O—C ceramic composite absorbing materials face a challenge of balancing structure and performance, and the porosity is difficult to accurately control, with pore size, shape, and distribution being disordered. The interface bonding and phase separation problems of heterogeneous element modified Si—O—C ceramics are prominent, and interface defects are easily formed between heterogeneous phases due to significant differences in chemical properties. Fiber reinforced Si—O—C ceramic composite absorbing materials have both structural load-bearing and absorbing functions, but there is a limited research on the effect of external loads on their absorbing performance at high temperatures.

The comparison of the effect of different sintering aids on the properties of aluminum nitride ceramics indicates that the oxide sintering aid has the most significant effect on the improvement of thermal conductivity and the most mature application technology. However, the sintering temperature required is relatively high, and the second phase of grain boundary generates, affecting the high-temperature performance. It is more suitable for high performance electronic packaging substrate materials. Fluoride sintering aids can significantly reduce the sintering temperature and directly deoxygenate through gas phase volatilization. There is no residual second phase in the grain boundary, but the high temperature volatiles will corrode the sintering equipment, and the sintering process is difficult to control, which is not suitable for industrial production. The composite sintering aid can further reduce the sintering temperature or optimize the grain boundary phase through the synergistic effect, but the formula design is more complicated, and the mechanism of action still needs to be further explored, which is suitable for the pursuit of extreme performance or specific functions. The application cost of other sintering aids is low, but the research is less, the universality is low, and it is still in the experimental research stage.

In the future, advanced characterization techniques can be used to reveal the mechanism of sintering additives, the migration path of oxygen impurities and the dynamic evolution process of grain boundary phase in the sintering process, which can provide a theoretical support for the design of sintering additive system. Nano- or submicron-sized sintering aids are obtained via optimizing the preparation process of sintering aids. Therefore, the utilization efficiency of sintering aids is improved, which is helpful to achieve densification at a lower addition amount. In addition, it can also be devoted to the development of new sintering additives, such as low rare-earth, no rare-earth or no residual sintering additive system, which can effectively reduce the residual impurities at the grain boundary and purify the grain boundary structure. A new type of nitrogen oxide grain boundary phase is constructed via accurately controlling the sintering atmosphere and the proportion of elements in the sintering aid. It can react with Al₂O₃ to form a rare-earth aluminum nitrogen oxide with a higher thermal conductivity and a better electrical insulation or JEM phase and other crystalline phases to replace the low thermal conductivity aluminate glass phase.

This review systematically analyzes the structure-property-processability relationships of CMA materials, highlighting the fundamental contradiction between their excellent performance and challenging densification. A strategic shift toward "performance adaptation and defect transformation" is proposed rather than pursuing densification at all costs, i.e., utilizing plate-like CMA grains as reinforcing phases in monolithic refractories, and exploiting decomposition behavior for lightweight structure design.

Future research directions include, 1) multi-scale mechanistic studies combining first-principles calculations, phase-field simulations, and in-situ characterization; 2) systematic investigation of structure-property relationships in CMA-based monolithic systems; and 3) exploration of novel composites and applications in emerging high-temperature processes. Through such integrated approaches, CMA materials are positioned to contribute significantly to the green transformation of high-temperature industries as environmentally friendly, high-performance refractories.

In summary, the toughening of Al₂O₃-based ceramics evolves from single-mechanism approaches to multi-scale, multi-mechanism synergistic strategies. The fracture toughness of Al₂O₃ composites is increased by 3-4 MPa·m^1/2 for monolithic alumina and by 10 MPa·m^1/2 for ZrO₂-toughened alumina (ZTA) and SiC whisker-reinforced systems. These materials are applied in high-performance cutting tools, ceramic armor, aero-engine hot-section components, semiconductor packaging substrates, and artificial joints. Nevertheless, several critical issues must be addressed to further advance their application:

1) Future research should focus on elucidating the coupled effects of multiple toughening mechanisms through in-situ characterization and multi-scale simulation. Understanding how cracks interact with complex microstructures will enable the design of materials with tailored energy dissipation pathways.

2) Advanced manufacturing techniques, particularly additive manufacturing, offer some opportunities for fabricating complex biomimetic architectures and compositionally graded structures. However, some issues such as fiber damage during sintering, dispersion of nano-reinforcements, and interfacial control must be resolved. External field-assisted techniques (e.g., magnetic or ultrasonic fields) can enable controlled alignment of reinforcements.

3) As application demands become more stringent, future Al₂O₃-based composites must exhibit high toughness and meet requirements for thermal shock resistance, oxidation resistance, electrical conductivity or insulation, and biocompatibility. This calls for a holistic design approach that integrates material selection, microstructure engineering, and performance optimization.

In summary, the development of high-performance Al₂O₃-based ceramic composites is moving toward greater complexity and functionality. With continued innovation in toughening mechanisms, processing technologies, and performance evaluation, these materials are expected to play an increasingly vital role in advanced engineering applications.

After decades of research, combustion synthesis of aluminum nitride powder successfully achieves a technological transition from ultra-high pressure to low/near-atmospheric pressure processing. There is also a relatively systematic understanding of the Al-N₂ combustion reaction process. Nevertheless, this technology is not used in industry. The main concern is an inferior powder performance, compared to the international start-of-the-art. The combustion-synthesized AlN powder has two main issues, i.e., broad particle size distribution and low specific surface area. The fundamental reason is a lack of in-depth understanding on the mechanism underlying the Al-N₂ combustion process. Therefore, a future research should develop a coordinated approach integrating theoretical depth with engineering application. In the theoretical realm, it is essential to conduct a thorough analysis of the reaction mechanism at the Al-N₂ combustion interface. This involves elucidating the morphological evolution of the powder via the in-situ dynamic characterization, clarifying the interaction between combustion wave parameters and powder performance. This provides a scientific basis for overcoming the performance limitations of combustion-synthesized AlN powder. Also, engineering requires a systematic development of post-treatment processes to improve sintering activity and batch stability in combustion-synthesized AlN powder. Concurrently, a reliable "burning product iteration" mechanism must facilitate its transition to industrial application.

Faced with worsening environmental problems and fossil energy depletion, renewable energy has become a focus of the global energy transition, whereas its intermittency and variability require large-scale energy storage systems. Commercial lithium-ion batteries are limited by safety hazards and high costs, making novel, safe, and low-cost energy storage systems critical. Thus, building-integrated structural energy storage systems have emerged, in which the separator, a core component, must perform multiple functions. Cement-based materials, because of their abundant raw-material sources and excellent stability, are ideal for separators and have been applied in supercapacitors and zinc-based batteries. Aqueous zinc-iodine batteries, featuring intrinsic safety, low cost, and good redox reversibility, are suitable for structural energy storage systems. The liquid active material system (iodide dissolved in electrolyte) avoids the drawbacks of solid iodine cathodes, and its combination with porous cement separators can meet building operation requirements (low maintenance, long-term stability). As a core factor regulating battery performance, electrolyte concentration determines active substance content and ion conduction. Thus, clarifying its effect on cement-based separators and zinc-iodine batteries and optimizing electrolyte formulation are essential. This study integrates foamed cement paste separators (FCPS) into zinc-iodine batteries. By regulating the cement paste pore structure through foaming and adjusting the zinc iodide concentration, this study aims to optimize ion conduction and mechanical and electrochemical properties. The study explores the influence of zinc iodide concentration on the physicochemical properties of FCPS and battery performance, and determines the optimal electrolyte formula, aiming to provide theoretical and experimental support for high-performance cement-based zinc-iodine batteries and building-integrated structural energy storage systems.

FCPS specimens were prepared by a foaming technique with a water-cement ratio of 0.5. After incorporating 0.1% aluminum powder by cement mass, the mixture was poured into molds for curing. For battery assembly, active carbon (AC), acetylene black, and polyvinylidene difluoride (PVDF) were mixed at a mass ratio of 8:1:1, blended with N-methylpyrrolidone (NMP) to fabricate AC cathodes with a loading of 2.48 mg·cm^-2. The electrolyte consisted of 2 mol/L zinc sulfate (ZnSO₄) and 0 to 0.20 mol/L zinc iodide (ZnI₂). FCPS were vacuum-soaked in the electrolyte for 7 d, and the zinc-iodine batteries were assembled with a cathode-separator-anode configuration. X-ray diffraction (XRD) and scanning electron microscopy (SEM) were used to characterize the phase and microstructure of FCPS. Compressive strength before and after electrolyte immersion was measured by a UTM5105 tester, and pore structure was analyzed by mercury intrusion porosimetry (MIP). Electrochemical behaviors including electrochemical impedance spectroscopy (EIS), cyclic voltammetry (CV), and galvanostatic chargedischarge (GCD) were tested to evaluate battery performance, and ionic conductivity, areal capacity, areal energy density, and areal power density were calculated.

The pristine FCPS presented a complex phase composition, consisting of unhydrated cement clinker minerals and various hydration products. After immersion in the electrolyte, the diffraction peak intensity of calcium hydroxide decreased, whereas characteristic peaks of zinc sulfate hydroxide hydrate (Zn₄(OH)₆SO₄⋅4H₂O, ZSH) and gypsum appeared, indicating chemical reactions between cement hydration products and the electrolyte. Pore-structure analysis revealed that the original FCPS had a porosity of 44%. After electrolyte soaking, the porosity decreased with obvious pore refinement, reduced pore connectivity and increased tortuosity. A porosity of 33% was obtained at 0.15 mol·L^-1 ZnI₂, yet the FCPS still maintained stable ion transport performance. The ionic conductivity of FCPS first increased and then decreased slightly as the ZnI₂ concentration increased, reaching a maximum of 10.20 mS·cm^-1 at 0.15 mol·L^-1, which was predominantly governed by the intrinsic conductivity of the electrolyte. The compressive strength of FCPS was substantially enhanced after electrolyte treatment and reached its maximum (7.54 MPa) at 0.15 mol·L^-1 ZnI₂, closely associated with pore filling and porosity evolution.

Electrochemical tests of FCPS-based zinc-iodine batteries indicated that increasing the ZnI₂ concentration reduced the solution resistance, with the lowest value obtained at 0.15 mol·L^-1. CV results confirmed the highly reversible I₂/I^- redox reaction, and the peak current increased with higher ZnI₂ concentration. GCD and rate-performance results showed that a moderate ZnI₂ concentration extended the charge-discharge plateau and improved areal capacity. Under the optimal electrolyte formula (2 mol·L^-1 ZnSO₄ and 0.15 mol·L^-1 ZnI₂), the battery delivered an areal energy density of 2.00 mW·h·cm^-2 at a power density of 0.25 mW·cm^-2, and retained 82% of its initial capacity after 1000 cycles, outperforming most previously reported cement-based batteries. Regarding the energy-storage mechanism, the multi-scale pore structure of FCPS provided sufficient electrolyte storage space and ion transport pathways. The in situ formation of ZSH and gypsum balanced mechanical stability and electrochemical performance. The optimized ZnI₂ concentration ensured high ionic conductivity and sufficient active iodine sources. The synergistic effect of these three factors enabled the integration of structural load-bearing and electrochemical energy storage for building applications.

In this study, a safe and environmentally friendly zinc-iodine battery is integrated with foamed cement paste to develop a novel energy storage system that integrates structural load-bearing capacity, electrochemical functionality, and large-scale application potential. A porous cement paste separator (FCPS) is fabricated via a foaming technique, enabling it to serve dual functions: acting as a battery separator that facilitates ion conduction and electrolyte retention while providing sufficient load-bearing capacity to maintain structural integrity. A zinc sulfate solution is used as the base electrolyte, into which different concentrations of zinc iodide are introduced to regulate the content of iodine active species and the ionic transport environment. The results demonstrate that the synergy between the porous structure and the optimal zinc iodide concentration is critical to enhancing both the ionic conductivity of the separator and the electrochemical performance of the battery. The foaming technique endows FCPS with abundant pore structures, which construct continuously connected ion transport channels and provide sufficient storage space for the electrolyte. Meanwhile, the optimal zinc iodide concentration (0.15 mol·L^-1) improves the ionic conductivity of the electrolyte and, as an active iodine source, increases the number of iodide ions participating in the I₂/I^- redox reaction. This synergy enables the foamed cement paste separator to achieve a porosity of 33%, an ionic conductivity of 10.20 mS·cm^-1, and a compressive strength of 7.54 MPa. Based on this optimal zinc iodide concentration, the assembled zinc-iodine battery delivers a high areal capacity of 1.60 mA·h·cm^-2 and an energy density of 2.00 mW·h·cm^-2 at a power density of 0.25 mW·cm^-2, with a capacity retention of 82% after 1000 cycles. This study provides a new strategy for large-scale energy storage and demonstrates the promising application of zinc-iodine batteries in building structural energy storage.

With its carbon neutrality target fast approaching, China's cement industry urgently needs to develop functional cement-based materials with high carbon sequestration capacity. low-calcium carbonatable binders (LCCB) show great potential for carbon reduction because of their low calcium-to-silica ratio and low calcination temperature; but their poor carbonation performance limits their carbon-reduction applications. To address this limitation, we systematically investigated the effects of barium (Ba) ion doping and magnesium nitrate (Mg(NO₃)₂) solution on the carbonation performance of LCCB by combining first-principles calculations with experimental tests. The results indicate that Ba ion doping increases the volume of the substitution polyhedra in wollastonite (CS) and rankinite (C₃S₂), providing a thermodynamic driving force for the dissociation of calcium ions during the early stages of carbonation. When the concentration of Mg(NO₃)₂ solution is 0.1 g/mL and the Ba ion doping level is 1% (molar fraction) of the calcium ions in the raw material, the initial reaction rate and carbonation activity of LCCB after 8 h of carbonation show significant improvement. In this case, the compressive strength and carbon sequestration rate are 101.7 MPa and 18.33%, respectively, representing increases of 53.63% and 55.34%. Analyses of carbonation products and microstructure indicate that Ba ion doping acts synergistically with Mg(NO₃)₂ to promote the rapid formation of CaCO₃ and amorphous silica gel, reduce porosity, and optimize the pore structure. These findings show that a synergistic modification strategy can effectively improve the carbonation performance of LCCB.

The mechanism by which Ba ions and Mg(NO₃)₂ synergistically enhanced the carbonation performance of LCCB was elucidated by combining first-principles calculations with experiments. The energy barrier for calcium ion dissolution decreased, and the synergy between Ba ions and Mg(NO₃)₂ also accelerated the early-stage carbonation rate of LCCB, creating favorable conditions for improving the carbon sequestration efficiency and compressive strength. Moreover, the marked increase in carbonation products effectively filled the larger pores, and the presence of aragonite further promoted the carbonation process. Thus, the synergy between Ba ions and Mg(NO₃)₂ effectively improved the carbonation performance of LCCB and provided an effective strategy for developing functional cement-based materials with high carbon dioxide sequestration capacity.

Ba ion doping and Mg(NO₃)₂ act synergistically to markedly improve the carbon sequestration rate and carbonation hardening performance of LCCB. During the early stage of carbonation, Mg(NO₃)₂ and Ba ions work together to increase the carbonation reaction rate and reactivity of LCCB, thereby speeding up the carbonation process. When the Mg(NO₃)₂ content reaches 1%, its synergistic effect with Ba ions is optimal. At this dosage, compressive strength, reactivity, carbon sequestration rate, and porosity all reach their optimal values, which shows the critical importance of the Mg(NO₃)₂ level. The findings of this study expand the theoretical framework for improving LCCB's carbonation performance, offer a scientific basis for advancing the use of carbon-sequestering cement-based materials, and foster green, circular, and synergistic progress in the building materials industry.

The design of the stress-applying part (SAP) in polarization-maintaining fibers (PMF) is a typical multi-variable, multi-objective optimization problem. The coupled effects of SAP diameter, B₂O₃ molar fraction and SAP edge-to-core distance determine attenuation, polarization-maintaining capability, mechanical reliability, and radiation resistance. Conventional trial-and-error design is therefore inefficient, especially when multiple performance constraints must be satisfied simultaneously.

Based on 500 experimental datasets, predictive models were established for eight performance indicators, including attenuation, post-irradiation loss, tensile strength, nd value, extinction ratio, temperature-induced extinction-ratio variation, beat length, and grinding crack probability. Three ensemble learning algorithms, i.e., random forest (RF), XGBoost, and gradient boosting regressor (GBR), were systematically compared via 5-fold cross-validation. SHAP analysis was employed to reveal the dominant effects of design variables. Furthermore, a large language model (LLM) was introduced as a natural-language interface and explanation layer to parse user requirements, diagnose infeasible constraints and provide minimum-relaxation suggestions.

The optimal models achieved R² values ranging from 0.76 to 0.99 with an average of 0.906, indicating that the nonlinear mapping between SAP parameters and performance metrics can be reliably captured. SHAP analysis revealed that the edge distance dominated attenuation-related indices, the SAP diameter governed mechanical and polarization-related properties, and the B₂O₃ molar fraction exerted the strongest effect on grinding crack probability. For 30 natural-language test cases, the LLM achieved 100% accuracy in indicator recognition and inequality-direction determination, and 85.0% exact-value accuracy. Across seven representative design scenarios, the proposed framework reduced the expected number of trial experiments by 91% on average and by up to 99.8% in the four-constraint scenario. When no feasible solution existed, the system could identify the bottleneck constraint and quantify the minimum relaxation required to recover feasibility.

A collaborative ML-LLM framework was developed for the inverse design of PMF SAPs. The method integrates quantitative prediction, mechanism-oriented interpretation and natural-language-driven interaction, thereby converting conventional trial-and-error design into an efficient data-driven screening process. This approach provides a practical pathway for intelligent design of polarization-maintaining fibers and may also be extended to other inorganic non-metallic materials with strongly coupled process-property relationships.