Wood composites have been widely applied in fields of construction， decoration， furniture， and transport. The fire safety has always been concerned. In a view of the combustion characteristics of wood composites， in the past 10 years， the two strategies for safeguarding on wood composites were reviewed as active fire protection （fire warning） and passive fire protection （flame retardancy）. As noted， wooden composites have no the “smart”characteristic. The fire warning function of composites is achieved by introducing temperature-responsive functional materials on its surface， such as thermally responsive semiconductor materials， thermochromic materials， shape-memory materials， etc.， and converting the temperature signal into a receivable signal （electrical signal， color， shape deformation， etc.） to transmit to the outside world， achieving timely warning of fires. The key to flame retardant treatment of wood composites lies in limiting the heat conduction and material transfer within the solid phase and between the gas-solid phase during the combustion process. In addition， the research progress in the flame retardant and smoke suppression properties of metal systems （magnesium/aluminum oxides， magnesium/aluminum layered double hydroxides）， boron systems， phosphorus nitrogen systems， biobased flame retardant systems， etc. in plywood， particleboard， and fiberboard was further summarized. As well as its relevant construction and synergistic flame retardant mechanism of the flame retardant compound system were further clarified. Moreover， the curing process of adhesives and mechanical properties of wood composites influenced by flame retardant compound systems were also discussed. Finally， it is pointed out that adopting early warning and mid to later-stage flame retardant methods can significantly improve the flame retardant and fire resistance of wood composites.

Wood-based scrimber is a new type of high-performance wood composite materials， in the process of directional recombination， a series of complex physical and chemical changes have taken place in wood and bamboo under the action of wet-heat-force and resin polymerization， and the original structural characteristics of wood and bamboo have changed significantly， forming a new multi-dimensional structure of wood-based scrimber. The formation of this new structural feature makes the physical and mechanical properties of the recombinant materials improved greatly compared with the properties of the original wood and bamboo. The new functions of flame retardant， anticorrosion， mildew resistance， weather resistance， and insect control of the wood-based scrimbers can be given by adding different additives in the process of recombination， which can overcome the defects such as soft material， low strength， uneven material and easy cracking in the artificial fast-growing forest. It solves the problems of small grade， easy cracking， and unequal material of bamboo， and can be used to replace high-quality wood， steel， cement， plastic， and other building materials. It has a wide range of prospects and is one of the effective ways to realize the efficient utilization of wood and bamboo in plantations. The macro and micro evolution of wood and bamboo in the process of recombination， the formation mechanism of multi-scale structure and multi-level adhesive interface of wood-based scrimbers， and the effects of multi-dimensional structure on the physical and mechanical properties of wood-based scrimbers were comprehensively reviewed， the viewpoint of cell-selective enhancement of wood-based scrimbers was put forward， and the scientific problems to be solved in wood-based scrimbers were summarized. It is suggested that the theoretical basis， manufacturing basis， and application basis of wood-based scrimbers should be studied at the cellular and molecular level， and the theoretical system of wood-based scrimbers should be constructed， so as to provide basic theory and technical support for the important national strategy of efficient utilization of wood resources in artificial fast-growing forests.

With the increasing awareness of environmental protection and the proposal of the national carbon peak strategy， the use of renewable bio-based resources for the preparation of flame retardant polymer materials has received widespread attention. Cardanol is an abundant and cost-effective biomass with multiple highly reactive functional groups， which is expected to be used for the preparation of commercial flame retardant polymeric materials. The preparations of cardanol-based flame retardant additives for modifying polyvinyl chloride， unsaturated polyester thermosets， and epoxy thermosets were summarized. Their performances were comparatively analyzed. The recent research progress in flame retardant cardanol-based epoxy thermosets， flame retardant cardanol-based benzoxazines， flame retardant cardanol-based ultraviolet-curable coatings， flame retardant cardanol-based polyurethane foams， and flame retardant cardanol-based phenolic foams were summarized. It is pointed out that the preparation of multifunctional flame retardant cardanol-based polymer materials with excellent comprehensive performance is the key direction of future research.

The phase transition temperature of single fatty acids is generally high and prone to leakage， which cannot meet the demand for using them as phase change materials for regulating the energy consumption of building air conditioning in summer.Based on conductor-like screening model for real solvents （COSMO-RS），136 binary low eutectic fatty acids of 7 medium chain fatty acids and 10 long chain fatty acids were designed and calculated by using COSMOthermX software，and the eutectic temperature and molar ratio of binary low eutectic fatty acids were predicted.Furthermore， the optimal combination was used as the core material， and melamine-urea-formaldehyde （MUF） resin was used as the wall material to prepare phase change microcapsules through in-situ polymerization. The effects of different process conditions （core-to-wall ratio， reaction temperature， reaction time， reaction speed，etc.） on the thermal and physical properties of the microcapsules were systematically discussed. The results show that the COSMO-RS model can judge the relationship between hydrogen bond donor （HBD） and hydrogen bond acceptor （HBA） more intuitively. The eutectic temperature （33.25 ℃） in theory is 98.08% similar to the experimental temperature （33.1 ℃） of lauric acid （LA）-myristic acid （MA） （LM） with the optimal combination of LA and MA with a molar ratio of 0.66 to 0.34. Under the conditions of a core-to-wall ratio of 2∶1， reaction time of 3 h， reaction temperature of 80 ℃， and stirring speed of 200 r/min， the encapsulation efficiency of MUF on the core material LM is 61.37%， which effectively solves the leakage problem and has potential application value in reducing the energy consumption of building air conditioning refrigeration.

The solar-driven interfacial evaporation （SDIE） can efficiently convert liquid water into steam using solar energy， providing a foundation for the development of eco-friendly and cost-effective freshwater production technologies. The photothermal material is the key platform for energy conversion， and the generated heat can be directly used for evaporation. In recent years， significant efforts have been made to enhance the efficiency of solar-driven water evaporation. Numerous innovative solar-thermal materials have been employed to achieve controlled and efficient solar-thermal conversion to meet energy-water challenges ranging from the microscale to the molecular level. On this basis， the latest research progress in carbon-based photothermal materials for SDIE technology is reviewed， focusing on the design， synthesis， and application of graphene， carbon nanotubes， natural plant-based carbon materials， carbon-based composite materials， and other photothermal materials that are currently widely used in the field of SDIE. Research findings related to the evaporation water collection rate were summarized. This aims to provide a reference for designing low-cost， efficient light absorption， chemical stability， and reusable and broad-spectrum absorption SDIE devices for off-grid desalination. Finally， the future development prospects of carbon-based materials for SDIE combined with artificial intelligence， power generation， sterilization， and all-weather operation are envisioned， to achieve eco-friendly， efficient， and multi-purpose water treatment and purification technologies.

Carbon nanomaterials are widely used in the treatment of water pollutants because of their structural characteristics such as large specific surface area， complex pore structure， and rich surface functional groups. This paper summarized the carbon sources and preparation methods of nanocarbon materials， analyzed the principles and influencing factors of nanostructure regulation of carbon materials， reviewed the research progress in nanocarbon adsorption of toxic pollutants in water， and put forward the bottlenecks that need to be broken through for the future industrial application of nanocarbon materials. Hydrothermal， pyrolysis and chemical vapor deposition are the common methods for the preparation of nanocarbon， and traditional carbon sources， such as sugars， petrochemicals， and biomass， can be used to obtain nanostructured carbon through the modulation of parameters such as preparation temperature and activator. Carbon nanotubes， carbon nanospheres， and nanoporous carbon have been developed for better contact with pollutants， thus exhibiting significant adsorption advantages for toxic pollutants such as phenols， benzenes， dyes， antibiotics， and heavy metal ions. In order to realize the wide application of nanocarbon adsorbent materials， further research is required to be carried out in the future on the development of green and efficient preparation process of nanocarbon， the exploration of the formation and evolution law of carbon structures， the design of macroscopic use scheme of nanocarbon， and the development of nanocarbon based composite materials.

The Cu-12Al-4Ni-1Mn-xB（x=0%，0.1%，0.2%，0.3%，mass fraction，the same below） shape memory alloys were prepared by vacuum arc melting furnace after introducing trace boron element into the alloy. The influence of boron addition on the microstructure， phase transformation， and mechanical properties of the alloy was investigated. The results show that the addition of boron significantly refines the grain size， with the grain size decreasing from hundreds of microns to （11±3.45） μm. The phase transformation temperature shifts to the high-temperature side after boron is added， indicating that the phase transformation process requires higher thermal activation energy. When the boron content is 0.2%， the microhardness of the alloy is enhanced， from （301.7±2.6）HV without adding boron element to （334.3±3.4）HV， which is attributed to grain refinement and the precipitation of hard and brittle borides. The tensile fracture strength and elongation are greatly improved， with the fracture strength increasing from （320±2.6） MPa to （788±17） MPa， and the elongation increasing from （1.44±0.05）% to （3.74±0.12）%. After solid solution annealing， the fracture strength and the elongation are both further increased to （856±10.7）MPa and （5.78±0.16）%， respectively. Analysis indicates that grain refinement strengthening， precipitation strengthening of borides， and solid solution strengthening are the main mechanisms for the improvement of mechanical properties. The fracture mode of the alloy shifts from brittle fracture to ductile fracture.

The effects of Cr on the microstructure of as-cast Al-Cu-Mg-Ag alloys and the distribution， size and number density of dispersoids after double-stage homogenization were investigated by OM， XRD， SEM-EDS and TEM methods. The effects of Cr on the dynamic recrystallization behavior of Al-Cu-Mg-Ag alloys under different equivalent strain were studied by high-throughput isothermal compression experiments. The results show that spherical Al₇（Cr， Mn） dispersoids with average diameter and number density of 67.4 nm and 4.7 μm^－2 are precipitated during the homogenization process， in addition to the rod-like T-Al₂₀Cu₂Mn₃ dispersoids. The opposite equilibrium distribution coefficient of Cr and Mn （K _Mn<1 vs K _Cr>1） reduces the area fraction of dispersoid-free zones from 29.5% to 13.8%， the average length of rod-like T-Al₂₀Cu₂Mn₃ decreases from 275.4 nm to 147.3 nm， and its number density increases from 3.5 μm^－2 to 10.4 μm^－2. EBSD and tensile test results indicate that the Al₇（Cr， Mn） dispersoids hinder the dislocation movement， reducing the transition from low-angle grain boundaries to high-angle grain boundaries during thermal compression， and inhibiting the dynamic recrystallization. The addition of Cr increases the mechanical properties of Al-Cu-Mg-Ag alloys at different temperatures， and the yield strength contributions of Al₇（Cr， Mn） dispersoids to the alloys at 25，250 ℃ and 300 ℃ are 21.9，16.2 MPa and 15.3 MPa， respectively.

The in-situ synthesized particle reinforced TC4 matrix composites were prepared by powder metallurgy pressureless sintering using polycarbosilane （PCS） as precursor. The thermal compression simulation experiments were conducted on TC4-1PCS （mass fraction of PCS is 1%） composites at 850-1100 ℃ and 0.001-1 s^-1 to analyze the stress-strain curves of the composites under different parameters using the Gleeble-3500 thermal simulation testing machine. The effects of deformation parameters on the reinforced phase particles， matrix structure and densification were analyzed by OM， SEM and EBSD methods. The results indicate that the TiC reinforced phase particles with the size of 5-10 μm and large amount of residual pores are observed in the TC4-1PCS composites before hot deformation. The β transition temperature（T _β） of TC4-1PCS matrix is 1000-1050 ℃. When deformed above T _β， matrix of composite consists of lamellar quenched martensite， while the matrix turns into duplex microstructure， when deformed below T _β. The deformation temperature determines the relative density and microstructure types of the composites， while the strain rate affects the phase size in the matrix and residual porosity. The densification of TC4-1PCS composites can be promoted by the increase of deformation temperature and the decrease of strain rate， while the increase of strain rate has obvious effect on the microstructure refinement. The microstructure refinement and densification of TC4-1PCS composites can be achieved by the deformation at 1050 ℃ and 0.1 s^-1.

The SiC/AlSi10Mg composites were fabricated via selective laser melting（SLM）. The phase characteristics， microstructure， anti-corrosion and wear resistance properties of SLM SiC/AlSi10Mg and SLM AlSi10Mg samples were investigated by XRD， SEM， EDS， EBSD， electrochemical test， and friction and wear test. The results show that in the 3.5% （mass fraction） NaCl solution， the corrosion current density of SLM SiC/AlSi10Mg （2.0827 μA/cm²） is lower than that of SLM AlSi10Mg （3.389 μA/cm²）， and the passivation film on the surface of SLM SiC/AlSi10Mg （7.1 nm） is thicker than that of SLM AlSi10Mg （1.9 nm）， indicating the SLM SiC/AlSi10Mg sample has better corrosion resistance than that of SLM AlSi10Mg. The reason can be attributed to that the addition of SiC causes the grain refinement， the increase of high grain boundary， and the interruption of the continuity of Al matrix， leading to the decrease of corrosion rate and the increase of corrosion resistance. In addition， the average microhardness for SLM SiC/AlSi10Mg composites （207.68±16.02）HV_0.2 is twice that of SLM AlSi10Mg alloy （103.58±7.41）HV_0.2， indicating its hardness and wear resistance are improved. Both the wear mechanisms of SLM AlSi10Mg and SiC/AlSi10Mg composites are mainly abrasive wear and oxidation wear.

The microstructures and properties of two kinds of zirconium-enriched α alloys （Ti₆₀Zr₄₀）₉₇Al₃（mass fraction/%，the same below） and （Ti₅₀Zr₅₀）₉₇Al₃ via different heat treatments were investigated and analyzed based on optical microscope （OM） observation， differential scanning calorimetric （DSC） measurement， X-ray diffraction （XRD） measurement， scanning electron microscope （SEM） observation and tensile tests at room temperature.The results show that after 850 ℃/40 min annealing， microstructures consisting of basket-weave α phase and a small amount of reticular β phase are formed in the alloys. After 850 ℃/40 min quenching， the acicular α' martensite phase is formed. After 850 ℃/40 min quenching and then 600 ℃/4 h aging， a large part of α' martensite phase converts into α phase， and the microstructures of the alloys consist of α and α'_remain phases. The yield strength of the T40Z3A alloy can reach 1100 MPa， with a favourable tensile elongation of 7%. The T50Z3A alloy exhibits higher strength but lower ductility than those of the T50Z3A alloy. Due to the higher content of Zr element， the T50Z3A alloy has more reticular β phase after annealing and more remaining α' martensite phase after quenching and aging， which results in higher strength and lower ductility.

The P-S-N curve of high and low cycle fatigue for aero-engine materials are essential to evaluate the service life of rotor components. However， it requires extensive experimental time and high material cost. Based on the physical-informed machine learning （PIML） method， a novel optimization method was proposed for combined high and low-cycle fatigue P-S-N curves with a small size sample， in which the equivalent principle of fatigue life and the consistency criteria of life distributions were introduced into the extreme learning machine（ELM） through its loss function. In addition， bi-level optimization was employed with the upper level of model input variables and the lower level of the ELM model parameters. Subsequently， the proposed PIML method was compared with a data-driven machine learning method and traditional P-S-N curve fitting methods through the fatigue test data.The results show that the method not only effectively solves the problem of nonlinearity between the stress level and the standard deviation of fatigue life， but also presents the highest accuracy of the predicted probabilistic lives.

C/C-SiC composites were prepared by chemical vapor infiltration （CVI） and reactive melt infiltration （RMI） using carbon fiber preforms with stitched and needle-punched structures. The microstructure and pore characteristics of C/C porous composites obtained from the two structural preforms， as well as the microstructure and flexural properties of C/C-SiC composites， were systematically studied. Results show that the pore size of stitched C/C porous composite is multimodal distribution， and the pores are mostly inter-bundle pores. The pore size of needle-punched C/C porous composite is unimodal distribution. Due to the addition of mesh， some inter-bundle pores are transformed into connected small pore networks. The simulated absolute permeability in the Z direction of the latter is slightly greater than that of the former， which is conducive to the subsequent RMI densification process of the latter （high density， low open-porosity and low residual metal）. The average flexural strength of stitched C/C-SiC composites is higher than that of needle-punched C/C-SiC composites， both of which exhibit a “pseudo plastic” fracture mode. The needle-punched C/C-SiC composite has a higher density and lower residual Si content， but its fiber volume content is lower， and the integrity of long straight fibers is poor， resulting in lower load-bearing property of the composite.

The high thermal conductivity of graphene shows great potential in the thermal management of electronic systems. Spherical Al₂O₃ was modified by polydiallyl dimethyl ammonium chloride （PDDA） to make the surface of Al₂O₃ positively charged， and then combined with negatively charged graphene oxide through electrostatic assembly. After high temperature thermal reduction， rGO@Al₂O₃ hybrid filler was obtained， and the hybrid filler was filled into the two-component silicone rubber. The thermal silicon gel enhanced by rGO@Al₂O₃ was further prepared. Then， the morphology and structure of the material during the preparation process were characterized by AFM， SEM， Raman， XRD， etc.， and the thermal conductivity and mechanical properties of thermal silicon gel were tested and analyzed. The thermal conductivity of thermal silicon gel which filled with rGO@Al₂O₃ prepared by 2% （mass fraction）GO is 0.817 W/（m·K）. Compared with the thermal conductive silicon gel filled with pure Al₂O₃， the thermal conductivity of rGO@Al₂O₃ silicon gel has been greatly improved.

In the process of hydrogen production from water splitting in alkaline environment， FeNi-based composites are one of the most promising catalysts to replace noble metals. Using Ni（CH₃COO）₂ and FeSO₄ as raw materials of metal ions， the molar ratio of Ni²⁺∶Fe²⁺ was controlled at 3∶1 and the total concentration of metal ions （Fe²⁺+Ni²⁺） was 0.6 mol/L. FeNi₃/Ni_{3- x} S₂/C composite nanomaterials were successfully prepared by in situ reaction of the elements of Ni，Fe，S with electrospinning and atmosphere heat treatment at 1000 ℃. The results show that the diameter of the nanoscale bead-chain is about 200 nm， the surface of the bead-chain is fluffy， and the elements of Fe， Ni， S， C are uniformly distributed in the nanoscale bead-chain matrix. The electrochemical analysis shows that the catalyst prepared from the FeNi₃/Ni_{3- x} S₂/C composite after heat treatment in 1000 ℃ atmosphere exhibites excellent oxygen evolution reaction （OER） properties in 1 mol/L KOH aqueous solution， and the overpotential is 278.59 mV.

So far， it is still a difficult task to develop electrocatalytic hydrogen evolution systems with comparable or even better efficiency than that of Pt systems. This study proves that the nanoporous gold electrode deposited on a flexible substrate coated with a titanium adhesion layer （Pt/Au-NHs/Ti/K） has excellent electrochemical water decomposition under laser irradiation. Localized surface plasmon resonance under light irradiation increases the electrocatalytic hydrogen evolution activity of the material， which shows that its performance is comparable to that of the commercial Pt electrode. Mechanism studies show that the plasma-excited Au nanoholes structure is an effective source of hot electrons， and the underlying Ti-based adhesive layer can effectively promote the separation of hot electrons and holes. In this system， the thermal effect is negligible， and the sudden change of the current density upon laser irradiation is demonstrated by the rapid generation and injection of charge carriers. The result shows that the Pt/Au-NHs/Ti/K electrode still has good stability under 10 mA·cm^-2 constant current density for 28 h.

To realize the practical application of solar photocatalysis and photoelectrocatalysis degradation of pollutants， the efficient， stable， and easily separable catalysts should be studied. Fe₃O₄@SiO₂@mesoporous TiO₂ （FST） composite photoelectrocatalysts were prepared by sol-gel and hydrothermal methods. The successful synthesis of nano FST was confirmed by characterization analysis. Fe₃O₄， SiO₂， and TiO₂ nanoparticles were coated layer by layer with a unique core-shell structure. The FST catalyst can be easily separated from the suspension under the applied magnetic field. The surface photocurrent response and impedance test results of FST show that its activity is significantly enhanced. The photoelectrocatalysis degradation of other organic pollutants under visible light is investigated using the synthesized FST， the 90 min photoelectrocatalysis degradation rates of methylene blue， rhodamine B， methyl orange， and amoxicillin are 98%， 95%， 92%， and 90%， respectively. The main active species capture experiments show that FST produces a large amount of h⁺ and ·OH through photoelectrocatalysis coupling， which degrades pollutants into CO₂， H₂O， and inorganic ions.

1D/2D g-C₃N₅/g-C₃N₄ heterojunction photocatalysts were prepared by a direct thermal polymerization method using melamine and 3-amino-1，2，4-triazole as raw materials. The crystal form， chemical composition， morphology and photoelectric chemical properties of the photocatalytic materials were characterized by XRD， XPS， SEM. Photocatalytic activity of 1D/2D g-C₃N₅/g-C₃N₄ heterojunction photocatalyst was studied using methyl orange（MO）as target pollutant and 500 W xenon lamp as visible light source. The active substances of the system were studied by active substance capture experiment and ESR characterization. The results show that the disordered stacking of one-dimensional g-C₃N₅ nanorods and two-dimensional g-C₃N₄ nanosheets increases the number of active sites. The formation of Z-scheme heterojunction between g-C₃N₅ and g-C₃N₄ improves the absorption intensity and spectral range of visible light， and inhibits the recombination of photoelectrons and holes. The superposition of π-π * conjugated systems similar to g-C₃N₅ and g-C₃N₄ reduces the mass transfer resistance of charge transfer and improves its photocatalytic activity. Under visible light irradiation for 30 min， 20 mg of 1D/2D g-C₃N₅/g-C₃N₄ photocatalytic material almost completely degraded 50 mL of 10 mg/L MO solution， and the apparent rate constant is 0.14836 min^-1. After 5 cycles， the photocatalytic degradation rate of 1D/2D g-C₃N₅/g-C₃N₄ photocatalytic material for MO is 92.2%， indicating its good stability. The capture experiment of active substances and ESR characterization show that the main active substances in the photocatalytic degradation of MO system by g-C₃N₅/g-C₃N₄ photocatalyst are •O {}_{\mathrm{2}}^{-} and h⁺， and the photocatalytic degradation of MO was a complex bond breaking and oxidation process.

To obtain particles that meet the requirements of spectral selective radiation for infrared stealth， the infrared optical properties of Ag/Ge core-shell structures were calculated using Mie scattering theory and finite element simulation， respectively. The peak extinction efficiency of particles with different Ag core and Ge shell size combinations was studied. The extinction efficiency curves of different size combinatorial calculators were selected on the contours of 6.5 μm， and the 0.3/0.848 μm core-shell structure was determined by comparison.The extinction efficiency was calculated by Mie scattering theory and finite element simulation. The curves of the two methods are very similar. The extinction peaks are all at 6.5 μm， and the peak extinction efficiency is 16.6 and 16.1， respectively， which verifies the reliability of the calculated results.By comparing the three-dimensional far-field radiation and electromagnetic power loss of particles in different wavelength， the particles have stronger radiation intensity and power loss density at 6.5 μm. The results indicate that the particle have a strong resonance with the incident field， which can be used for the selective absorption of infrared radiation in this band.

To meet the design requirements of multi-band and miniaturization antennas in mobile communication system， combined with the structural advantages of metamaterials， a 2D/3D tunable dual-band paper-based metamaterial antenna was designed based on origami technique. In order to illustrate the characteristics of the paper-based antenna， such as easy processing， low cost， and easy carrying， prototype antennas were fabricated by coating conductive silver on different paper-based materials. The simulation and measured results show that the antenna can operate at 2.45 GHz and 1.40 GHz in 2D and 3D states respectively， and the operating frequency band can be controlled by adjusting the folding angle of the inner ring. In addition， the radiation patterns of 2D and 3D antennas were studied respectively. The main radiation direction of the 2D antenna is perpendicular to the plane of the antenna， while the main radiation direction of the 3D antenna is controlled by the folding angle of the inner ring. The paper-based metamaterial antenna provides new ideas for antenna design to achieve switchable operating frequency bands and has a wide application in portable mobile terminal and multi-band communication.