The critical challenge of chip thermal dissipation fundamentally constrains both power consumption and operational longevity, underscoring the imperative demand for advanced packaging materials exhibiting superior thermal conductivity coupled with ultralow thermal expansion. Magnesium-based packaging systems demonstrate considerable promise in this strategic domain; however, current research efforts remain notably sparse, particularly regarding SiC particulate (SiCP)-reinforced magnesium matrix composites. In this investigation, we prepared SiCP-reinforced magnesium matrix composites through optimized stir casting methodology and systematically investigated their thermophysical characteristics. Remarkably, the composite incorporating merely 25 vol.% SiCP exhibited exceptional thermal performance metrics: a thermal conductivity of 178.5 W/(m·K) and a coefficient of thermal expansion as low as 16.8 × 10−6 K−1. Furthermore, molecular dynamics simulations were employed to elucidate thermal transport mechanisms at Mg/SiC interfaces, revealing that chromium interlayer implementation substantially enhances interfacial thermal conductance compared to direct bonding configurations. This comprehensive study not only validates the efficacy of SiCP reinforcement in optimizing magnesium matrix composites’ thermophysical properties but also establishes Mg/SiCP composites as a cost-competitive solution for next-generation thermal management applications.

Developing in situ spectroelectrochemistry methods,which can provide detailed information about species trans-formation during electrochemical reactions,is very important for studying electrode reaction mechanisms and improving battery performance.Studying real-time changes in the surface of electrode materials during normal operation can be an effective way to assess and optimize the practical performance of electrode materials,thus,in situ and in operando characterization techniques are particularly important.However,batteries are hard to be studied by in situ characterization measurements due to their hermetically sealed shells,and there is still much room for battery characterizations.In this work,a specially designed battery based on the structure of coin cells,whose upper cover was transparent,was constructed.With such a device,acquisition of diffuse reflectance spectra of electrode materials during charging and discharging was realized.This not only provided a simple measurement accessory for diffuse reflectance spectroscopy(DRS),but also complemented in situ characterization techniques for batteries.Taking commonly used cathode materials in lithium-ion batteries(LIBs),including LiFePO4(LFP),NCM811 and LiCoO2(LCO)as examples,we managed to find out the response relationships of different electrode materials to visible light of different wavelengths under ordinary reflectance illumination conditions.Heterogeneity of different cathode ma-terials on interaction relationships with the lights of different wavelengths was also revealed.This work demonstrated the capability of guiding wavelength selection for different materials and assessing electrochemical performances of in situ diffuse reflectance spectroelectrochemistry.By combining electrochemistry with diffuse reflectance spectroscopy,this work made an effective complementary for spectroelectrochemistry.

Self-propelled micro/nanomotors have attracted great attention for environmental remediation, however, their use for radioactive waste detection and removal has not been addressed. Engineered micromotors that are able to combine fast detection and highly adsorptive capability are promising tools for radioactive waste management but remain challenging. Herein, we design self-propelled micromotors based on zeolite imidazolate framework (ZIF-8)-hydrogel composites via inverse emulsion polymerization and show their potential for efficient uranium detection and removal. The incorporation of magnetic ferroferric oxide nanoparticles enables the magnetic recycling and actuation of the single micromotors as well as formation of swarms of worm-like or tank-treading structure. Benefited from the enhanced motion, the micromotors show fast and high-capacity uranium adsorption (747.3 mg g-1), as well as fast uranium detection based on fluorescence quenching. DFT calculation confirms the strong binding between carboxyl groups and uranyl ions. The combination of poly(acrylic acid-coacrylamide) with ZIF-8 greatly enhances the fluorescence of the micromotor, facilitating the high-resolution fluorescence detection. A low detection limit of 250 ppb is reached by the micromotors. Such self-propelled micromotors provide a new strategy for the design of smart materials in remediation of radioactive wastewater.

The primary cause of the decrease in thermal conductivity of conventional thermal conductive magnesium alloys is electron scattering brought on by solute atoms. However, the impact of phase interface on thermal conductivity of magnesium alloys is usually disregarded. This study has developed a Mg-Si-Zn-Cu alloy with high thermal conductivity that is distinguished by having a very low solute atom content and a significant number of phase interfaces. The thermal conductivity of the Mg-1.38Si-0.5Zn-0.5Cu alloy raises from its untreated value of 133.2 W/(m·K) to 142.2 W/(m·K), which is 91% of the thermal conductivity of pure Mg. This is accomplished by subjecting the alloy to both 0.8wt% Ce modification and T6 heat treatment. The morphology of eutectic Mg2Si phase is changed by Ce modification and heat treatment, and as a result, the scattering of electrons at the Mg2Si/Mg interface is reduced, resulting in increase of the alloy's thermal conductivity.

The influence of curing temperature on the strength development of cement-stabilized mud has been well documented in terms of strength-increase rate and ultimate strength. However, the strength development model is not mature for the extremely early stages. In addition, there is a lack of studies on quality control methods based on early-stage strength development. This paper presents a strength model for cement-stabilized mud to address these gaps, considering various curing temperatures and early-stage behaviors. In this study, a series of laboratory experiments was conducted on two types of muds treated with Portland blast furnace cement and ordinary Portland cement under four different temperatures. The results indicate that elevated temperatures expedite strength development and lead to higher long-term strength. The proposed model, which combines a three-step conversion process and a hyperbolic model at the reference temperature, enables accurate estimate of the strength development for cement-treated mud with any proportions cured under various temperatures. With this model, a practical early quality control method is introduced for applying cement-stabilized mud in field projects. The back-analysis parameters obtained from a 36-h investigation at temperature of 60 degrees C demonstrated a sufficient accuracy in predicting strength levels in practical applications. (c) 2024 Institute of Rock and Soil Mechanics, Chinese Academy of Sciences. Published by Elsevier B.V. This is an open access article under the CC BY-NC-ND license (http://creativecommons.org/licenses/by-nc-nd/ 4.0/).

The increasing integration and power requirements of electronic devices present significant challenges in thermal management. Heat sinks with high thermal conductivity can effectively enhance heat exchange between electronic devices and cooling mediums. To augment the heat exchange surface area, heat sinks feature numerous thin-walled fins, necessitating high deformability from the materials employed in constructing the heat sinks. This study presents the successful fabrication of a high thermally conductive magnesium alloy (ZC0505) with exceptional plasticity by compositional design and using the continuous squeeze casting-extrusion (CSCE) technique. The addition of low levels of 0.5 mass% Zn and 0.5 mass% Cu elements to pure magnesium results in Mg-Zn-Cu alloys reinforced by diffuse Laves phase with high thermal conductivity. After the CSCE process, this alloy achieves a thermal conductivity of 160.1 W/(m center dot K), which exceeds that of pure magnesium, and exhibits a significant elongation of 26.1%, which can be attributed to the refined grain, recrystallization, and spheroidization of the precipitated phases.

Development of magnesium alloys with exceptional mechanical properties and high thermal conductivity is a prominent subject in the field of thermal conductive magnesium alloys. Rare-earth containing magnesium alloys are known for their ability to achieve higher strength. However, they often exhibit higher density and higher cost.This study developed a high-strength and high-conductivity magnesium alloy without the need for rare earth elements through considered composition design. By utilizing the pinning effect of Mg2Si and solute drag effects of Zn and Cu, a fine-grained magnesium alloy with an average grain size of merely 4.5μm was achieved. The simultaneous introduction of hard Mg2Si particles and ductile Cu-rich particles allow Mg-1.38Si-0.5Zn-0.5Cu alloy (SZC100) to attain a desirable combination of strength and plasticity. Althogh free of rare-earth elements, this magnesium alloy demonstrates a thermal conductivity of 141.5 W/(m·K), a yield strength of 238 MPa, and an elongation of 16.2%.

Tin oxide, characterized by its exceptional theoretical capacity, emerges as a highly promising alternative anode in the pursuit of high-energy-density lithium-ion batteries (LIBs). However, inherent limitations in conductivity and structural integrity impede the fulfillment of its energy storage potential. Herein, sophisticated SnO2-carbon nanorods (SnO2/C NRs) derived from a tin-based metal-organic framework are developed for superior lithium storage. The ultrafine SnO2 nanocrystals are embedded within a hollow and porous rod-like architecture, ensuring fast multidirectional charge transfer and well-accommodated volume variation during the lithiation/ delithiation process. Moreover, the integration of the carbon matrix further promotes electron conduction and reinforces the structural integrity towards fast, efficient, and durable electrochemistry. As a result, the SnO2/C NRs electrodes demonstrate excellent long-term cyclability with a minimal capacity fading rate of 0.089 % per cycle over 500 cycles, and a commendable rate capability with a highly reversible capacity of 922.1 mAh g- 1 at 3 C. This work establishes a unique and insightful paradigm for designing advanced electrode materials towards energy-dense next-generation LIBs.

As a ceramic material, AlN has very good thermophysical and mechanical properties. In addition, AlN is an effective refining agent for Mg alloys because it has a lattice constant similar to that of Mg. Therefore, AlN is an ideal reinforcement for magnesium matrix composites (MMCs), and is attracting increasing attention. This review addresses the development of preparation technologies for AlN-reinforced Mg matrix composites. The mainstream preparation techniques include stir casting, melt infiltration, powder metallurgy, and in-situ methods. In addition, the advantages and disadvantages of these techniques are analyzed in depth, and it is pointed out that the next direction for the preparation of high-performance AlN-reinforced MMCs is less aluminization and multiple technologies integration.

Swimming microrobots that are actuated by multiple stimuli/fields display various intriguing collective behaviors, ranging from phase separation to clustering and giant number fluctuation; however, it is still chanllenging to achieve multiple responses and functionalities within one colloidal system to emulate high environmental adaptability and improved tasking capability of natural swarms. In this work, a weak ion-exchange based swarm is presented that can self-organize and reconfigure by chemical, light, and magnetic fields, showing living crystal, amorphous glass, liquid, chain, and wheel-like structures. By changing the frequency and strength of the rotating magnetic field, various well-controlled and fast transformations are obtained. Experiments show the high adaptability and functionality of the microrobot swarm in delivering drugs in confined spaces, such as narrow channels with turns or obstacles. The drug-carrying swarm exhibits excellent chemtherapy for Hela and CT26 cells due to the pH-enhanced drug release and locomotion. This reconfigurable microswarm provides a new platform for biomedical and environmental applications.

Solar-driven interfacial evaporation provides a promising pathway for sustainable freshwater and energy generation. However, developing highly efficient photothermal and photocatalytic nanomaterials is challenging. Herein, substoichiometric molybdenum oxide (MoO3-x) nanoparticles are synthesized via step-by-step reduction treatment of l-cysteine under mild conditions for simultaneous photothermal conversion and photocatalytic reactions. The MoO3-x nanoparticles of low reduction degree are decorated on hydrophilic cotton cloth to prepare a MCML evaporator toward rapid water production, pollutant degradation, as well as electricity generation. The obtained MCML evaporator has a strong local light-to-heat effect, which can be attributed to excellent photothermal conversion via the local surface plasmon resonance effect in MoO3-x nanoparticles and the low heat loss of the evaporator. Meanwhile, the rich surface area of MoO3-x nanoparticles and the localized photothermal effect together effectively accelerate the photocatalytic degradation reaction of the antibiotic tetracycline. With the benefit of these advantages, the MCML evaporator attains a superior evaporation rate of 4.14 kg m-2 h-1, admirable conversion efficiency of 90.7%, and adequate degradation efficiency of 96.2% under 1 sun irradiation. Furthermore, after being rationally assembled with a thermoelectric module, the hybrid device can be employed to generate 1.0 W m-2 of electric power density. This work presents an effective complementary strategy for freshwater production and sewage treatment as well as electricity generation in remote and off-grid regions.

The galloping of iced conductors is a serious threat to the safe operation of power systems. Establishing an accurate galloping model of iced conductors has always been a difficult point in galloping research. Therefore, the sparse identification of nonlinear dynamics (SINDy) algorithm is used to identify the galloping model from noise measurement data. A theoretical model of galloping of iced quad bundle conductors is established. Meanwhile, the algorithm is used to identify the simulated data of the theoretical model. The parameter identification ability of the algorithm under noisy velocity measurement is analyzed. An excellent denoising method was selected for data preprocessing, and then the model identification effect of the algorithm after data preprocessing is studied. Besides, the accuracy of the prediction model based on this algorithm and the support vector regression (SVR) prediction model under different training data lengths are compared. The results show that the model identified by the SINDy algorithm in the noise measurement data after data preprocessing has high accuracy and robustness. Moreover, the amount of data used is small. The model identified by this algorithm plays an important role in the rapid investigation, prediction and early warning of galloping phenomena.

Efficient oil/water separation tackles various issues in occasions of oil leakage and oil discharge, such as environmental pollution, recollection of the oil, and saving the water. Herein, a compact superhydrophobic/superoleophilic graphitic carbon nitride nanolayer coated on carbon fiber networks (CNBA/CF) is designed and synthesized for efficient gravity-driven oil/water separation. The CNBA/CF shows excellent oil absorption and an impressive oil/water filtration separation performance. The flux reaches the state-of-art value of 4.29 × 105 L/m2/h for dichloromethane with separation efficiency up to 99%. Successive oil absorption tests, long-term filtration separation, and harsh conditions experiments confirm the remarkable separation and chemical structure stability of the CNBA/CF filter. Besides, the CNBA/CF demonstrates good photocatalytic antifouling ability thanks to the extended visible light absorption and improved charge separation. This work combines the material surface wettability modulation with a photocatalytic self-cleaning property in the fabrication of efficient oil/water separation materials while overcoming the filter fouling issue.

A comprehensive and intuitive understanding of railway track health is crucial for railway managers to ensure operational safety and rational allocation of maintenance and repair resources. A health evaluation model based on matter element analysis for railway track grids is proposed. The model divides a continuous railway track line into adjacent "segments" of the same specific length, called "track grids". A comprehensive evaluation model for track health is established using the matter element analysis method in extension theory. The model fully considers the objectivity of expert knowledge and data and uses an improved entropy weight method to determine indicator weights. By evaluating the entire system or a single index, maintenance measures can be enacted appropriately. The proposed model’s effectiveness is verified through the collection of real condition data of 1447 track grids on a railway line in western China.

Multi-material additive manufacturing (MMAM) offers a flexible way to produce complex and functionally graded materials (FGMs) with varying mechanical, electrical or chemical properties, leading to more sophisticated and cost-effective part designs and fabrications. However, the lack of material-aware printing capabilities in existing CAD and CAM software poses a significant challenge. MMAM with existing CAD/CAM software can only fabricate multi-material parts with sharp multi-material interfacial transitions. To address this challenge, we propose a novel adaptive voxelization and parameter assignment technique integrated with the commercial CAD software Rhinoceros 3D to achieve material-dependent variable printing toolpath generation. The proposed method enables adaptive process parameter assignment at variable resolutions. To meet the multi-material design specifications, the proposed method can generate G-code commands with adaptive process parameter assignment. The key novelty and contribution of this work is the mapping between the solid CAD design to the final printing toolpath with parametric transitions in the multi-material interfaces. Various transition functions, including radial distribution and linear transitions, can be defined to achieve graded material distributions. Graded voxel size is also achievable with finer resolution at multi-material interface regions to enable precise control of process parameters and material distributions, whilst coarse voxels are used for deposition in single-material regions. The proposed method sets the foundation for producing complex multi-material components by AM.

Multi-component thermal fluid flooding is an increasingly mature technology for heavy oil recovery. However, the production of associated gas containing highly corrosive CO2/O-2/SO2/H2S/H2O impurities can lead to corrosion and perforation failure in gathering pipelines. This study systematically investigated the effects of temperature/CO2/O-2/SO2/H2S on L245NS steel corrosion in a CO2-O-2-SO2-H2S-H2O environment and analyzed the correlation between these factors and corrosion rate. The corrosion behavior of L245NS steel in a CO2-O-2-SO2-H2S-H2O environment was investigated through weight-loss experiments and surface characterization techniques. An empirical model for predicting the corrosion rate in this environment was established based on the obtained results. The results indicated that the sequence of importance for corrosion rate was as follows: O-2 (0.8181) > H2S (0.7511) > Temperature (0.7491) > CO2 (0.7312) > SO2 (0.7017). Surface char-acterization revealed that the predominant corrosion products were FeCO3, FeS2, FeS, Fe(OH)(3), FeOOH, Fe3O4, Fe2O3, elemental sulfur and FeSO4.4H(2)O. The corrosion reaction involved CO2/O-2/SO2/H2S while synergistic reactions between SO2-O-2 and SO2-H2S further promoted corrosion. Finally, an empirical model for the corrosion rate of L245NS steel in a CO2-O-2-SO2-H2S-H2O environment was established. The fitting error ranged from 0.03% to 8.99%, and the verification error ranged from 2.62% to 14.83%. This model can provide a valuable reference for preventing and controlling pipeline corrosion.

Swarms of self-propelled micromotors can mimic the processes of natural systems and construct artificial intelligent materials to perform complex collective behaviors. Compared to self-propelled Janus micromotors, the isotropic colloid motors, also called micromotors or microswimmers, have advantages in self-assembly to form micromotor swarms, which are efficient in resistance to external disturbance and the delivery of large quantity of cargos. In this minireview, we summarize the fundamental principles and interactions for the assembly of isotropic active particles to generate micromotor swarms. Recent discoveries based on either catalytic or external physical field-stimulated micromotor swarms are also presented. Then, the strategy for the reconstruction and motion control of micromotor swarms in complex environments, including narrow channels, maze, raised obstacles, and high steps/low gaps, is summarized. Finally, we outline the future directions of micromotor swarms and the remaining challenges and opportunities.

The integration of solar‐driven interfacial evaporation and electricity co‐generation is considered a promising approach to simultaneously alleviate freshwater scarcity and the energy crisis. However, affected by intermittent solar irradiation/uncontrollable weather, the overall performance of solar‐driven evaporation in the real world is greatly reduced. Herein, inspired by antifreeze proteins in beetles that survive in extreme climates, all‐weather solar‐driven interfacial evaporators with a sandwich structure are designed. The top and bottom layers composed of MnO 2 ‐modified cotton cloth are used for photothermal conversion and water transport, meanwhile, the middle layer made of a phase change microcapsule/hydrogel composite serves for heat storage and release. Under 1 kW m −2 irradiation, the evaporator exhibits a high evaporation rate of 2.67 kg m −2 h −1 and an efficiency of 89.5%. In the dark, the heat released from the phase change layer supports an evaporation rate of 0.43 kg m −2 h −1 , 3.6 times that of pure water. Additionally, assembled with a thermoelectric module, the hybrid device achieves a stable output electricity power of 0.42 W m −2 under 1‐sun illumination and a prolonged output for 30 min in the dark. This work provides a novel approach for full‐time solar‐powered steam‐electricity co‐generation and a proof of concept for biomimetic steam generation/heat management integration.

Porous hydrogel with intrinsic hydrophilicity and reduced vaporization enthalpy has emerged as a rising star for solar-driven interfacial water distillation and desalination. However, the development of facile, general and scalable approaches capable of simultaneously engineering the molecular and microporous structure is urgently needed for hydrogel evaporators but a daunting challenge. Herein, a freeze-soak method based on Hofmeister effect is used to fabricate porous hydrogel evaporators with tunable molecular and microporous structure in large scale. The interconnected porous structure endows the hydrogel with adjustable water transport rate and exceptional desalination performance, while the changeable crystallinity allows the hydrogel with tunable water states. Benefiting from these properties, the hydrogel shows a high evaporation rate of 3.52 kg m(-2)h(-1) with the conversion efficiency of 97.2 % under 1 Sun irradiation. Additionally, the integration of the hydrogel evaporator with a thermoelectric module enables the low-grade heat to electricity conversion. A power density of 0.65 W m(-2) is achieved under 1 Sun irradiation. It is anticipated that the Hofmeister effect-mediated porous hydrogel without the assistance of freeze-drying will lay a solid foundation for the industrial fabrication of hydrogel for energy conversion and storage, environmental remediation, etc.

In this study, in-situ 3 wt% Mg2Si/Al–Cu composites have been prepared by a novel continuous squeeze casting-extrusion (CSCE) process assisted with ultrasonic treatment (UT) for the first time. Different from the traditional semi-continuous hot extrusion process, the new method eliminates billet homogenization annealing and preheating. After UT + CSCE, the fine Al2Cu and eutectic Mg2Si phases in the UT + SC (squeeze casting) billet are further crushed to form a fibrous microstructure distributed along the extrusion direction (ED). Moreover, the α-Al grains are elongated along the extrusion direction, and the proportions of LAGBs (low-angle grain boundaries) and HAGBs (high-angle grain boundaries) are 72.3% and 27.7%, respectively. Meanwhile, fiber textures with orientations <111>//ED and <100>//ED are formed, and the ratios of the two textures are 60.9% and 30.5%, respectively. After UT + CSCE, the ultimate tensile strength (UTS), yield strength (YS) and elongation of the in-situ 3 wt% Mg2Si/Al–Cu composite are 330 MPa, 250 MPa and 11%, and its YS and elongation are 23.2% and 69.2% higher than those of the UT + SC billet, respectively. Compared with the Al–Cu alloy prepared by UT + CSCE, its UTS and YS are increased by 11.9% and 38.9%, respectively.